The advantage of the approach taken by the present invention is to produce single immunogens containing protective antigens from a range of pathogens. Such chimeras greatly simplify the development of combination vaccines, in particular, with the view ultimately to produce single dose multivalent vaccines. Multivalent vaccines are currently made by separately producing pathogens and/or their pertinent antigens and combining them in various formulations. This is a labour intensive, costly and complex manufacturing procedure. In contrast, the availability of a single immunogen capable of protecting against a range of diseases would solve many of the problems of multivalent vaccine production. Several chimeric immunogens of the type provided herein may be combined to decrease the number of individual antigens required in a multivalent vaccine.
Human Parainfluenza virus types 1,2,3 and Respiratory syncytial virus types A and B are the major viral pathogens responsible for causing severe respiratory tract infections in infants and young children. It is estimated that, in the United States alone, approximately 1.6 million infants under one year of age will have a clinically significant RSV infection each year and an additional 1.4 million infants will be infected with PIV-3. Approximately 4000 infants less than one year of age in the United States die each year from complications arising from severe respiratory tract disease caused by infection with RSV and PIV-3. The WHO and NIALD vaccine advisory committees ranked RSV number two behind HIV for vaccine development while the preparation of an efficacious PIV-3 vaccine is ranked in the top ten vaccines considered a priority for vaccine development.
Safe and effective vaccines for protecting infants against these viral infections are not available and are urgently required. Clinical trials have shown that formaldehyde-inactivated and live-attenuated viral vaccines failed to adequately protect vaccines against these infections. In fact, infants who received the formalin-inactivated RSV vaccine developed more serious lower respiratory tract disease during subsequent natural RSV infection than did the control group. [Am. J. Epidemiology 89, 1969, p.405-421; J. Inf. Dis. 145, 1982, p.311-319]. Furthermore, RSV glycoproteins purified by immunoaffinity chromatography using elution at acid pH induced immunopotentiation in cotton rats. [Vaccine, 10(7), 1992, p.475-484]. The development of efficacious PIV-3 and RSV vaccines which do not cause exacerbated pulmonary disease in vaccines following injection with wild-type virus would have significant therapeutic implications. It is anticipated that the development of a single recombinant immunogen capable of simultaneously protecting infants against diseases caused by infection with both Parainfluenza and Respiratory syncytial viruses could significantly reduce the morbidity and mortality caused by these viral infections.
It has been reported that a protective response against PIV-3 and RSV is contingent on the induction of neutralizing antibodies against the major viral surface glycoproteins. For PIV, these protective immunogens are the HN protein which has a molecular weight of 72 kDa and possesses both hemagglutination and neuraminidase activities and the fusion (F) protein, which has a molecular weight of 65 kDa and which is responsible for both fusion of the virus to the host cell membrane and cell-to-cell spread of the virus. For RSV, the two major immunogenic proteins are the 80 to 90 kDa G glycoprotein and the 70 kDa fusion (F) protein. The G and F proteins are thought to be functionally analogous to the PIV HN and F proteins, respectively. The PIV and RSV F glycoproteins are synthesized as inactive precursors (FO) which are proteolytically cleaved into N-terminal F2 and C-terminal F1 fragments which remain linked by disulphide bonds.
Recombinant surface glycoproteins from PIV and RSV have been individually expressed in insect cells using the baculovirus system [Ray et al., (1989), Virus Research, 12: 169-180; Coelingh et al., (1987), Virology, 160: 465-472; Wathen et al., (1989), J. of Inf. Dis. 159: 253-263] as well as in mammalian cells infected with recombinant poxviruses [Spriggs, et al., (1987), J. Virol. 61: 3416-3423; Stott et al., (1987), J. Virol. 61: 3855-3861]. Recombinant antigens produced in these systems were found to protect immunized cotton rats against live virus challenge. More recently, hybrid RSV F-G [Wathan et al., (1989), J. Gen Virol. 70: 2625-2635; Wathen, published International Patent application WO 89/05823] and PIV-3 F-HN [Wathen, published International Patent Application WO 89/10405], recombinant antigens have been engineered and produced in mammalian and insect cells. The RSV F-G hybrid antigen was shown to be protective in cotton rats [Wathan et al., (1989), J. Gen. Virol. 70: 2637-2644] although it elicited a poor anti-G antibody response [Connors et al., (1992), Vaccine 10: 475-484]. The protective ability of the PIV-3 F-HN protein was not reported in the published patent application. These antigens were engineered with the aim to protect against only the homologous virus, that is either RSV or PIV-3. However, it would be advantageous and economical to engineer and produce a single recombinant immunogen containing at least one protective antigen from each virus in order simultaneously to protect infants and young children against both PIV and RSV infections. The chimeric proteins provided herein for such purpose also may be administered to pregnant women or women of child bearing age to stimulate maternal antibodies to both PIV and RSV. In addition, the vaccine also may be administered to other susceptible individuals, such as the elderly.


The present invention relates to a scanning tunnel microscope and more particularly to a scanning tunnel microscope which is designed in such a way that a position of a desired portion on a specimen to be observed with the scanning tunnel microscope is previously positioned by utilizing a scanning electron microscope so that an observation can be then made with respect to the positioned portion.
With respect to a prior art apparatus which is constructed by combining a scanning tunnel microscope (hereinafter, referred to as simply "an STM", when applicable) with a scanning electron microscope (hereinafter, referred to as simply "a SEM", when applicable), the description is shown in an article "Review of Scientific Instruments 60", April, 1989, pp. 789 to 791. In the apparatus described in this article, a specimen is mounted on a specimen holder in such a way that its surface makes an angle of 45.degree. with an electron beam of the SEM. The specimen is then moved towards a probe of the STM by a coarse movement mechanism referred to as an inchworm utilizing a piezoactuator, which serves to linearly move a specimen in a direction perpendicular to the electron beam, so as to approach to a position at a predetermined distance from the probe which allows the tunnel effect to be generated. The probe of the STM is attached to a fine movement mechanism referred to as a piezotripod, so that it is moved along the surface of the specimen, thus performing a scanning operation. The above-mentioned elements constituting the STM are fitted to a stage of the SEM within a specimen chamber of the SEM.
In the prior art apparatus described above, there is provided therein only the coarse movement mechanism which serves lineally to make the specimen approach to the probe to be located in an area allowing generation of the tunnel effect, and also a SEM stage for searching for the probe by utilizing the SEM is not clear in construction.
JP-A-63-116349 (the term JP-A used herein means that the patent application was laid open to public inspection but has not been examined) and JP-A-63-298951 disclose that a position on a specimen to be observed with a STM is previously positioned by utilizing a SEM and that a specimen is adapted to be moved in a two dimensional manner along its surface with its surface being inclined at 45.degree. with an electron beam.
Moreover, JP-A-64-79603 discloses a microscope which is designed in such a way that a specimen is observed at a low magnification with a SEM and the same specimen is observed at a high magnification with a STM.
The prior art described above discloses that a position to be observed with an STM with a higher magnification is determined using a SEM, and then an observation is made with the STM. However, when the apparatus is actually operated, even if the position of the specimen is set in such a way that an observation position determined by the SEM goes to a predetermined position within a visual field of an electron microscope image by the SEM, it is not necessarily easy to make the probe of the STM scan accurately over the observation position determined by the SEM since the position of the probe of the STM is not precisely defined with respect to an image by the SEM.
In other words, only when the relationship among the specimen, the probe and the electron beam is accurately determined, the position positioned by the SEM can be observed accurately at a high magnification with the STM.


In order to stabilize a downhole emplacement such as a bored or drilled hole forming a well, it typically requires multiple materials that are dry blended in a pneumatic bulk plant and then injected down hole in a cementing process. These dry materials can include cement, pozzolanic fly ash, silica, chemical additives that alter the cure time (accelerators/retarders), fluid loss materials, viscosifiers, defoamers, friction reducers, extenders, and other chemical additives that alter a product's performance downhole. These materials are blended in the pneumatic bulk plant and require multiple transfers to obtain a product that is sufficiently homogenous. Once the blending process is complete, the performance characteristics of the product are set since the blended mix cannot be re-mixed once it is removed from the bulk plant location.
The blended dry product is then transported to the site of the oil/gas well using bulk storage units (e.g. bulk trailers, or transports). The product is then introduced to a pumping and mixing truck, such as by pneumatic conveying. In the mixing truck, water is added to the dry product in specific measured quantities to achieve a desired density product slurry that can be measured using a densitometer. The mixing of water with the dry product is done “on the fly”—that is, continually mixed and pumped: pumping operations are not stopped during mixing operations in which the desired product slurry density may be achieved automatically through an electronic control system. The mixing truck may include controls such as water and cement throttling valves that are adjusted dynamically via the electronic control system to ensure that the measured density of the fluid is in agreement with a desired density that is typically determined by the user.
When the slurry mix has achieved the desired density, it can be pumped downhole within a well form casing that is pre-positioned in the well. A drilling or work over-rig may be used to pump the slurry mix in which an annular space between the wellbore and casing are filled incrementally as the slurry mix is pumped.


The present invention relates to a steam iron having a low temperature pressing surface. The common steam iron of today's market utilizes an aluminum soleplate which provides the pressing surface and also includes a boiler, generally of the flash boiler type. It is necessary to heat this aluminum mass to a sufficiently high temperature, generally over 300.degree. F., when the iron is used as a steam iron in order to assure that the water that enters the flash boiler reaches a sufficiently high temperature to be turned into steam and maintain this state so that it does not leave the iron in water droplets and thus water stain the clothes. The pressing surface which is also a part of this aluminum mass is thus maintained at a relatively high temperature which would be damaging to the low temperature fabrics of today's market. Therefore, in irons of this type steam ironing of low temperature fabrics is not possible and thus the iron must be used as a dry iron when low temperature fabrics are ironed.
Prior art has also attempted to solve this problem by utilizing a plastic add-on shoe disposed beneath the plate of the iron. Such shoes, however, have not found general acceptance. Furthermore, the irons upon which they are used are not designed with this intent in mind and thus are not calibrated with respect thereto thus making the temperature settings for use with the shoe purely guesswork.


1. Field of the Invention
The invention is directed to insect repellent formulations which contain polar solvents, have low viscosity, and are deliverable by piezoelectric device.
2. Description of the Related Art
Sprayable insecticidal compositions are known and generally comprise an insecticide and a solvent, in addition to other components. As the common insecticides are non-polar, the most common solvents used for this purpose are themselves non-polar, e.g. hydrocarbon solvents, such as hexane and petroleum solvent blends available under the trade names Shellsol and Isopar, for example.
While hydrocarbon solvents are effective to dissolve most common non-polar insecticides, they tend to have low flash points and to otherwise pose environmental and health risks. Therefore, it is desired to develop sprayable insecticidal compositions which avoid or minimize the use of these solvents. An insecticide formulation deliverable by piezoelectric delivery system which minimizes or avoids the use of non-polar solvents would be an advancement in the art.
Low-flash point solvents typically have high volatility. High volatility results in unintended evaporation of the insecticidal formulationxe2x80x94so-called xe2x80x9clatent losses.xe2x80x9d The problem of latent losses is particularly acute when the formulations are intended for delivery by a piezoelectric device over an extended period of time. For this and other reasons, there is a need in the art for insecticidal formulations using low-volatility solvents which are deliverable by piezoelectric device.
U.S. Pat. No. Re. 31,927 discloses electrostatically sprayable insecticidal formulations. High-boiling, high flash point hydrocarbon solvents, such as Isopar L are used to dissolve these insecticides, but lesser amounts of a polar component, such as n-butanol or cyclohexanone are added to raise the viscosity and reduce the resistivity of the final formulations. The viscosity of these solutions is believed to be too high for effective delivery using a piezoelectric delivery system.
U.S. Pat. No. 5,935,554 is directed to an aerosol space spray which, in some embodiments, is an insecticidal composition. The composition includes an insecticide, a solvent and a propellant, and in some cases a co-solvent. Where an insecticide is used, the solvent is Shellsol T, with ethanol as a co-solvent.
European Patent No. 897,755 discloses aerosol and piezoelectric-deliverable insecticide compositions. Mentioned as solvents for the piezoelectric systems are aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, alcohols, esters, ethers, and ketones, with a particular preference given to aliphatic saturated hydrocarbons having 5 to 18 carbon atoms. EP 897,755 does not identify polar solvents that would dissolve insecticides, nor does it identify the properties that render a polar solvent suitable for use with a piezoelectric delivery system.
Typical prior art liquid atomizers utilize a large amount of propellants in the formulation. Conventionally, to obtain the desired characteristics of an aerosol for dispersion into the air, the formulations contain minimal active ingredients, a solvent for the active ingredient and a suitable propellant. The active ingredient usually constitutes less than 1% w/w. The solvent is present in the order of 10-20% w/w and the propellant constitutes 80-90% w/w. In most cases of such aerosol formulations, the solvent is a hydrocarbon solvent and the propellant a fluorocarbon or hydrocarbon. Alternatively, the propellant is partially substituted with water, wherein the weight percentage being water is in the range of 30-40% w/w. Therefore it is evident that to deliver one gram of insecticide conventionally requires the release to the atmosphere of between 80 and 250 g of volatile organic compounds (VOC""s). Volatile organic compound (VOC) is the general name given for compounds with an appreciable vapor pressure, for example, fluorocarbons, hydrocarbons, e.g. butane, etc., commonly used as propellants.
It is an object of the invention to provide an insecticidal composition which can be delivered with a piezoelectric delivery system. In particular, it is desired to provide an insecticidal composition with a sufficiently low viscosity that it can be delivered with a piezoelectric delivery system in the form of a fine mist or puff to provide continuous insect repellency throughout a room without settling too rapidly on surrounding surfaces.
Another object of the invention is to provide a low viscosity insecticidal composition that is not harmful or hazardous and which minimizes or eliminates the use of hydrocarbon solvents. In particular, it is desired to provide an insecticidal composition that exhibits overall low toxicity to humans and which will not be harmful to the respiratory system. It is also an object of the invention to provide an insecticidal composition that is non-flammable, and exhibits sufficiently low vapor pressure that latent losses are minimized when the formulation is used with a piezoelectric delivery device.
These and other objects of the invention are achieved by providing an insecticidal composition comprising an insecticide and at least one polar solvent having a vapor pressure below about 5 mm Hg at 25xc2x0 C., where the insecticidal composition has a viscosity lower than 2.6 centipoise at 25xc2x0 C. In preferred embodiments, the polar solvent comprises dipropylene glycol dimethyl ether.
Preferably, more than 75% of the solvent is a polar solvent or combination of polar solvents and co-solvents. In particularly preferred embodiments, the composition is substantially free of hydrocarbon solvents.
In preferred embodiments, the insecticidal composition according to the invention comprises an insecticide in an amount between about 3 percent by weight and about 20 percent by weight of the composition, while the solvent or solvents comprise between about 80 and 97 percent by weight of the composition.
The preferred formulations according to the invention are not emulsions and do not require propellants for delivery.
As understood by those of skill in the art, a piezoelectric liquid atomizer comprises an orifice plate which is vibrated by an actuator made of a piezoelectric material, such as lead zirconate titanate (PZT) or lead metaniobate (PN). Upon application of an alternating electrical field across the piezoelectric actuator it expands and contracts and causes the orifice plate to vibrate. The vibrating orifice plate contacts a liquid and as a result liquid droplets are propelled ultrasonically through the orifices in the plate and ejected into the atmosphere.
The diameter of the orifices in the orifice plate of a piezoelectric liquid delivery system determines the size of the droplets produced. The diameter generally ranges between about 1 and about 25 microns, preferably from about 4 to about 10 microns. The size of the orifices is tailored such that energy consumption by the device is minimal while the size of the droplets is small enough to permit the droplets to remain suspended in the air and evaporate without collecting on the surrounding surfaces.
Droplets having an average size greater than about 15 to 20 microns and larger have a tendency to settle out of the air, onto the delivery device and other surfaces. Thus, it is advantageous to provide a solution that will produce droplets having a size less than 20 microns, preferably less than 15 microns. An average droplet size of about 10 microns has been observed to stay suspended in air for a suitable length of time to effectively kill insects in a room.
The low viscosity insecticidal compositions according to the invention are particularly suitable for piezoelectric delivery systems powered by low voltage batteries, such as conventional xe2x80x9cAxe2x80x9d, xe2x80x9cAAxe2x80x9d, xe2x80x9cAAAxe2x80x9d, xe2x80x9cCxe2x80x9d, xe2x80x9cDxe2x80x9d cell batteries and the like. In a particularly preferred embodiment, the insecticidal composition of the present invention is adapted for use with a piezoelectric delivery system powered by a single 1.5 Volt xe2x80x9cAAxe2x80x9d size battery.
Piezoelectric systems that may be used to deliver the insecticidal compositions of the present invention are disclosed in co-pending application Ser. Nos. 09/449,601, 09/498,859, 09/518,882, and 09/519,603, all of which are incorporated by reference herein in their entirety. However, the compositions described and claimed herein are not limited to those deliverable by the systems described in the above-referenced patent applications.
By way of description, without limiting the invention, the insecticidal composition may be delivered to a room via a piezoelectric delivery system at a rate between about 20 and about 40 mg/hour, with the insecticidally active component making up between about 3 and 20 percent of that amount.
It is generally preferred to obtain a delivery rate of about 1 to about 2 mg per hour of active insecticide so that a 10 ml bottle operated 8 hours a day will have a useful life between about 30 and about 70 days.
The use of a piezoelectric delivery device capable of prolonged delivery poses constraints on the solvent systems that can be used in insecticidal formulations. These constraints include: (1) the ability to solubilize insecticide, (2) low viscosity, (3) low vapor pressure, (4) high flash point, and (5) low toxicity (generally evidenced by high solubility in water).
xe2x80x9cSolvent systemxe2x80x9d as used herein means the combination of all the solvents used in the insecticidal composition. xe2x80x9cMain solventxe2x80x9d as used herein means a solvent comprising more than 50 percent by weight of the final formulation. xe2x80x9cCo-solventxe2x80x9d means any solvent used in addition to the main solvent.
Generally, the active must be soluble in the solvent system of the formulation in an amount between about 2 percent by weight to about 10 percent by weight to be deliverable by a piezoelectric device.
It has been found that for the effective delivery of insecticide by a piezoelectric delivery system, low viscosity is critical. It is believed that a viscosity lower than 10 centipoise (cp) is necessary to obtain a suitable puff or mist using the preferred delivery systems according to the invention. The insecticidal compositions according to the invention preferably exhibit a viscosity of lower than about 2.6 cp, more preferably, lower than about 2.2 cp.
As the insecticides are generally high viscosity substances it is necessary to utilize a solvent system having a viscosity at least less than about 2.6 cp, and preferably less than 2.2 cp or lower, in the insecticidal formulations according to the invention.
In preparing the compositions of the present invention, the inventors have sought to lessen or eliminate the use of solvents which are harmful to inhale, such as those designated R20, R21 or R22; solvents irritating to the eyes or skin such as those designated R36 and R38; flammable solvents, such as those designated R10; and solvents harmful to the respiratory system when ingested, vomited and subsequently aspirated into the lungs, such as those designated R65. In general, it is desired that solvents having designation R20, R21 or R22 not exceed 25% by weight of the final formula; solvents having designation R36, R38 not exceed 20% of the final formula; and solvents having designation R65 not exceed 10% of the final formula. The R10 designation refers to low-flashpoint materials. It is desired that the formulations according to the invention have less than 20% by weight of solvents designated R10.
As used herein, a xe2x80x9clow toxicityxe2x80x9d composition is one containing less than 25 weight percent of R20, R21, or R22 solvents, less than 20 weight percent of R36 or R38 solvents, or less than 10 weight percent R65 solvent, and which has less than 25 weight percent hydrocarbon solvents overall. Limiting the use of solvents having the above-described hazard designations avoids conspicuous label designations, which is important in in formulating a commercially acceptable insecticidal product. Generally, polar solvents having high solubility in water are low-toxicity solvents.
The most preferred compositions according to the invention are substantially free of hydrocarbon solvents. xe2x80x9cSubstantially freexe2x80x9d in this context allows for the presence of minor amounts of hydrocarbon solvents such as will not change the fundamental characteristics of the composition.
High solubility in water is a good indicator of low overall toxicity. Therefore, glycol ethers are good candidates to use as solvents or co-solvents in connection with the invention. For example, propylene glycol ethyl ether, propylene glycol n-propyl ether, ethylene glycol ethyl ether, and ethylene glycol propyl ether all have viscosities below 2.6 centipoise at 25xc2x0 C., good solubility in water, and vapor pressure below 5 mm Hg at 20xc2x0 C. Propylene glycol methyl ether has good water solubility and low viscosity; although its high vapor pressure (8.1 mm Hg at 20xc2x0 C.) precludes its use as a main solvent, it can be used as a co-solvent. Ethylene glycol butyl ether, dipropylene glycol methyl ether, dipropylene glycol n-propyl ether, dipropylene glycol t-butyl ether, and tripropylene glycol methyl ether can also be used, although the viscosities of these glycol ether solvents are all greater than 2.6 cp, which may limit their use somewhat.
Diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol propyl ether, and diethylene glycol butyl ether are all water soluble, have low vapor pressures and high flash points. However, their viscosities at 25xc2x0 C. range between 3.9 and 4.7 cp, which may limit their use in formulations according to the invention.
It is desirable to keep the flash point of the final formula higher than about 55xc2x0 C. (131xc2x0 F.), as measured by the Penske Martin Close Cup Method (ASTM D93), more preferably higher than about 60xc2x0 C. (140xc2x0 F.).
The inventors herein have found that a solvent having a vapor pressure less than about 5 mm Hg at 20xc2x0 C. must be used to avoid unacceptable latent losses in an insecticidal formulation over an extended period of delivery. Hydrocarbon solvents commonly used in analogous environments, such as Isopar C, Isopar G, Isopar L, Isopar E, and the like, have all been found to lead to unacceptable latent losses.
Dipropylene glycol dimethyl ether (DMM) has been found to meet the constraints of low vapor pressure (0.55 mm Hg at 20xc2x0 C.), low viscosity (1 cp at 25xc2x0 C.), and high water solubility as an indicator of low toxicity (35 g/100 ml water). Alone among the glycol ether solvents having these characteristics, DMM has a relatively high flash point (149xc2x0 F. (65xc2x0 C.)). Thus, in the preferred embodiments, DMM is the main solvent, used with one or more co-solvents.
In preferred embodiments, the insecticidal composition includes a co-solvent. The function of co-solvents is to improve the efficacy of the final formulation while still enabling the formulation to meet the constraints of high flash point, low volatility, low viscosity and low toxicity (as evidenced by high solubility in water). Accordingly the cosolvents themselves may have lower flash points, higher volatility, higher viscosity and lower solubility than the main solvent and still be acceptable for use in the solvent system according to the invention. Isopar L solvent, a hydrocarbon with very little water solubility and having an R65 hazard designation, may be used as a co-solvent in amounts less than about 10 percent by weight. Propylene glycol methyl ether acetate, which has a flash point of 114xc2x0 F. and also carries an R36 hazard designation may be used as a co-solvent in amounts less than about 20 percent by weight with respect to the final formulation. Propylene glycol n-propyl ether (PnP), which has a flash point of 119xc2x0 F. may be used as a co-solvent in amounts up to about 20 percent by weight. A preferred co-solvent is the cyclic amide N-methylpyrrolidone (NMP) used in amounts less than about 20 percent by weight.
The insecticides usable in the composition according to the invention are not particularly limited and include, without limitation, pyrethroid insecticides such as pyrethrin, allethrin, tetramethrin, resmethrin, etc.; organic phosphorus insecticides such as fenitrothion, ciafos, diazinon, etc.; carbamate insecticides such as carbaryl. The synthetic pyrethroids transfluthrin ((IR-trans)-2,3,5,6-tetraflurophenyl) methyl 3-(2,2-dichloroethyenyl)-2,3-dimethylcyclopropane carboxylate, a synthetic pyrethroid), and prallethrin ((RS)-2-Methyl-4-Oxo-3-(2-Propynyl) Cyclopent-2-enyl (1RS)-cis, transchrysanthemate), sometimes referred to as Etoc, are particularly preferred. Teflutlrin, pynamin, pynamin forte, and natural pyrethrum are all acceptable for use.
In some of the following examples, Pyrethrum 20 is used as an insecticide. Pyrethrum 20, available from Waxdale, is a mixture of pyrethrins in petroleum distillates and vegetable extracts, having 20 percent by weight active ingredients.


Raman spectroscopy is a powerful tool for quantitative analysis of the composition and concentration of a certain analyte within a sample. In the application of physiological detection, such an optical measurement is usually carried out in the near-infrared region. The Raman signal is often small, for instance the ratio of Raman signal strength to excitation signal strength is less than 10−10. Moreover the Raman signal is ultra-sensitive to the measurement conditions, such as laser fluctuation, optical bleaching, temperature variation, the changes in sample size and sample shape and optical alignment. Therefore internal standard method is usually applied during the analysis of the Raman signal. The basic principle of internal standard method is to measure a sample signal and a standard signal simultaneously (or nearly simultaneously) and their ratio, which is invariant from the measurement conditions, is used in the quantitation. Conventionally, a Grating-CCD (or Grating-photodiode-array) spectrometer is used as the detector in these systems. However, these systems are expensive and throughput is limited by the grating at required spectral resolution.
Recent developments in Microelectromechanical systems (MEMS)-based spectrometer made it possible to use single detector to replace the CCD system in Raman signal detection system which significantly reduces the system cost. However, the throughput of such single-detector system is still limited by the use of grating. In order to achieve high throughput system, different designs have been disclosed. One of such design uses a sweeping light source, for instance a tunable laser, to obtain the Raman spectrum. Another approach uses a tunable filter, for instance an acousto-optical tunable filter, to obtain the Raman spectrum. Nonetheless, the costs of these new designs are not acceptable in constructing a home-used device for monitoring physiological parameters.


This invention relates generally to dynamoelectric machines, and in particular to a cover which is removably mounted to an endshield of a motor and which simultaneously seals against the endshield and provides unhindered access to fasteners for connecting the machine to an adjacent part, such as a pump.
Dynamoelectric machines such as electric motors have widespread use in converting energy between electrical current and mechanical motion. A substantial concern is that motors are frequently exposed to contaminants such as moisture and dust which damage or degrade the motors. Electrical component parts used in control and operation of the motors are particularly vulnerable to damage from water, which can produce short-circuits and safety hazards. Consequently, electronic components are mounted at locations where they may be protected from environmental contamination. For example, a motor for an above-the-ground swimming pool filter pump is typically placed outdoors, adjacent to the pool, where it is exposed to both rain and splashes. The motor has an electric power cord with wires that connect at a terminal board holding electronic components. The terminal board is mounted inside the motor behind a sealed cover to prevent moisture from reaching the terminal board or its components, thereby lowering the risk of contamination. Typically, the cover includes a steel plate and gasket which are mounted to an endshield of the motor using two or more small threaded fasteners. Unfortunately, removal and replacement of that cover increases the time required to access the terminal board for assembly or maintenance, thereby degrading efficiency.
Some motors have a dome-type cover which encloses a portion of the endshield, but these covers have the drawback of requiring additional installation time during assembly. Either they fail to provide an effective seal so that a second, steel plate cover is still required, or alternatively they obstruct access to bolt fasteners used in connecting the motor to an adjacent part, such as a pump or support. In the latter instance, the dome-type cover must be removed for manipulating the bolt fasteners even though there is no need to access the terminal board or electronic components. That exposes the electronics to potential contamination during the time when the cover is removed. More importantly, a person may inadvertently damage electronic components when removing or re-installing the cover, or may inadvertently re-install the cover at an unsealing, mis-aligned orientation, causing subsequent leaks and damage.
Among the several objects and features of the present invention may be noted the provision of a dynamoelectric machine which is connectable to an adjacent part while being simultaneously protected from moisture or contaminants; the provision of such a machine which reduces the time required for connection to the adjacent part; the provision of such a machine which has an effective seal; the provision of such a machine which provides unhindered access to fasteners; the provision of such a machine which reduces risk of damage to electronic components; and the provision of such a machine which is economical.
In general, a dynamoelectric machine of the present invention is connectable to an adjacent part while being simultaneously protected from moisture or contaminants. The machine comprises a casing having a hollow interior defining a housing and a longitudinal axis. An endshield is positioned generally at an end of the casing and mounts at least one electrical component used in operation of the machine. The endshield has a wall projecting in a longitudinal direction and further has at least two openings for receiving fasteners to connect the machine to the adjacent part. The at least two openings define respective fastening locations on the endshield. A cover is removably mounted on the endshield and defines an enclosure to protect the at least one electrical component. The cover is configured for an overlapping fit with at least a portion of the wall of the endshield to prevent passage of moisture or contaminants into the enclosure. The cover is further configured to avoid covering the at least two openings when mounted on the endshield such that the fastener locations lie outside of the enclosure and are accessible for connecting the machine to the adjacent part while the cover remains mounted on the endshield.
In another aspect, a method according to the present invention protects a dynamoelectric machine from moisture or contaminants while connecting the machine to an adjacent part. The machine has a casing, two opposite endshields, and at least two fasteners connecting the endshields and extending beyond the casing for connection to the adjacent part. The method comprises the steps of mounting a cover on a portion of one of the endshields with a fit which overlaps a sidewall of the endshield to prevent passage of moisture or contaminants. The cover is configured to avoid covering the fasteners. The fasteners are manipulated to connect the machine to the adjacent part while the cover remains mounted on the endshield.
Other objects and features of the present invention will be in part apparent and in part pointed out hereinafter.


1,1,2-Trichloro-1,2,2-trifluoroethane (known in the trade under the name F113) has been widely used in industry for cleaning and degreasing highly-varied solid surfaces (metal components, glasses, plastics, composites) for which the absence or at least the lowest possible residual content of impurities, in particular of organic nature, is required. F113 was particularly well suited to this use because of its nonaggressive nature with regard to the materials used. This product was used in particular in the field of the manufacture of printed circuits, for removing the residues of the substances used to improve the quality of the soldered joints (denoted by the term solder flux). This removal operation is denoted in the trade by the term "defluxing".
Mention may also be made of the applications of F113 in the degreasing of heavy metal components and in the cleaning of mechanical components of high quality and of great accuracy, such as, for example, gyroscopes and military, aerospace or medical equipment. In its various applications, F113 is generally used in combination with other organic solvents (for example methanol), in order to improve its cleaning power. It is then preferable to use azeotropic or near-azeotropic mixtures. The term "near-azeotropic mixture" is understood to mean, within the sense of the present invention, a mixture of generally miscible chemical compounds which, under certain specific conditions of proportions, temperature and pressure, boils at a substantially constant temperature while retaining substantially the same composition. When it is heated to reflux, such a near-azeotropic mixture is in equilibrium with a vapour phase, the composition of which is substantially the same as that of the liquid phase. Such azeotropic or near-azeotropic behaviour is desirable in ensuring satisfactory operation of the devices in which the abovementioned cleaning operations are carried out and in particular in ensuring the recycling by distillation of the cleaning fluid.
F113 is also used in fields, in particular in optics, where it is required to have available surfaces which are devoid of water, that is to say surfaces where water is only present in the form of traces undetectable by the measurement method (Karl Fischer method). F113 is, for this purpose, employed in drying (or dewetting) operations on the said surfaces, in combination with hydrophobic surface-active agents.
However, the use of compositions based on F113 is now forbidden as F113 is one of the chlorofluorocarbons (CFCs) suspected of attacking or damaging the stratospheric ozone.
In these various applications, F113 can be replaced by 1,1-dichloro-1-fluoroethane (known under the name F141b), but the use of this substitute is already controlled because, although low, it still has a destructive effect with regard to ozone.
Application EP 0,512,885 discloses a composition, comprising from 93 to 99% by weight of 1,1,1,3,3-pentafluorobutane and from 1 to 7% of methanol, which can be used as substitute for F113. 1,1,1,3,3-pentafluorobutane, also known in the trade under the name F365mfc, has no destructive effect with regard to ozone.
Application EP 0,856,578 discloses a composition, comprising from 10 to 90% by weight of 1,1,1,2,3,4,4,5,5,5-decafluoropentane, from 10 to 90% of dichloromethane and from 0 to 10% of methanol, which can also be used as substitute for F113. 1,1,1,2,3,4,4,5,5,5-Decafluoropentane, known in the trade under the name 43-10mee, also has no destructive effect with regard to ozone.


Mainframe manufacturers and the telecommunications industry are primary users of backplanes on which are mounted a substantial number of daughter cards carrying electronic components thereon. The backplane provides conductive traces or circuits to electrically interconnect the components on the several cards and to provide access to other backplanes and outside electric gear. The predominate method of mounting the cards on the backplane and electrically interconnecting the circuits (and hence the components) is by means of card edge connectors. Such connectors include a card receiving slot, i.e. a card slot, with conductive contact members having spring arms or cantilever beams positioned along one or both sides of the slot to engage traces on the card inserted therein and further having depending leads electrically engaging the backplane. In some connectors, the arms or beams are preloaded into the slot and the cards are frictionally inserted thereinto. Provided the number of contact members are not too great, the force required to insert the card is acceptable. However, cards having a large number of traces require connectors wherein the large number of contact members prohibit frictional insertion. In these cases, connectors having camming mechanisms which either cam the arms or beams out of the slot prior to inserting the card, e.g. as disclosed in U.S. Pat. No. 3,793,609, or into the slot after insertion of the card, e.g. as disclosed in U.S. Pat. No. 4,586,772, are used.
In each type connector, the method of obtaining the normal force, i.e. the force exerted on the conductive pads or traces on the card by the arms or beams, predetermines the type of cantilever beam or spring arm to be used therein. For example, in the first type, the spring arms must be resilient enough so that they can be moved out of the slot with acceptable levels of force applied to the camming mechanism and still have sufficient inherent spring force to bear against the card and obtain good electrical contact therewith. In the second type of ZIF connector, the spring arms or beams must be made of stiffer material to stand up under the biasing forces continually exerted against them by the camming mechanism. In this type connector, a higher normal force may be obtained which is required in some operational uses. However, a greater force is required to actuate the camming mechanism which could lead to breakage if the components are not strong enough to withstand the forces.
It is now proposed to provide a ZIF card edge connector wherein the spring arms on the contact members are hinged and have a large moment arm which provides a mechanical advantage so that lower forces will actuate the camming mechanism and a high normal force will still be obtained.


Photovoltaic cells are commonly used to transfer energy in the form of light into energy in the form of electricity. A typical photovoltaic cell includes a photoactive material disposed between two electrodes. Generally, light passes through one or both of the electrodes to interact with the photoactive material, thereby generating charge carriers (i.e., electrons and holes). As a result, the ability of the photoactive material to absorb light and general charge carriers can limit the overall efficiency of a photovoltaic cell.


In recent years, with rapid spread of information-related equipment such as personal computers, video cameras, and mobile phones, batteries used as a power source therefor have been actively developed. Further, in the automobile industry, development of batteries having high output and high capacity for electric vehicles or hybrid vehicles has been promoted. Among various batteries, a lithium battery has an advantage of a high energy density.
In this regard, as a solvent of a liquid electrolyte for a lithium battery, it is known to use a glyme that is one of oligoethers. For example, Patent Literature 1 discloses a Li-based secondary battery which includes a cathode containing a specific electrode active material, a liquid electrolyte in which at least a part of a glyme and a Li salt forms a complex, and an anode. This technique is intended to improve rate characteristics and a power density of a battery. In addition, Patent Literature 2 discloses a liquid electrolyte which contains only a glyme as a solvent of the liquid electrolyte and an alkali metal salt as a solute of the liquid electrolyte, in which at least a part of the glyme and the alkali metal salt forms a complex. This technique is intended to provide a high-voltage liquid electrolyte having high thermal stability and being usable in general in-vehicle secondary batteries.


Industrial coatings are surface protective coatings (paint coatings) applied to substrates and typically heat cured to form continuous films for decorative purposes as well as to protect the substrate. A protective coating ordinarily comprises an organic polymeric binder, pigments, and various paint additives, where the polymeric binder acts as a fluid vehicle for the pigments and imparts rheological properties to the fluid paint coating. Upon curing, the polymeric binder hardens and functions as a binder for the pigments and provides adhesion of the dried paint film to the substrate. The pigments may be organic or inorganic and functionally contribute to opacity and color in addition to durability and hardness, although some paint coatings contain little or no opacifying pigments and are described as clear coatings. The manufacture of paint coatings involves the preparation of a polymeric binder, mixing of component materials, grinding of pigments in the polymeric binder, and thinning to commercial standards.
Epoxy resins are particularly desirable for use in protective surface coating materials as a vehicle or polymeric binder for pigments, fillers, and other additives where the epoxy resins advantageously provide toughness, flexibility, adhesion, and chemical resistance. Water-dispersed coating compositions containing epoxy resins are highly desirable for can coating compositions and particularly useful for interior surfaces. Comings for soft drink and beer cans, for instance, are critical due to taste sensitivity wherein such can coatings must not alter the product taste of canned beverages. Taste problems can occur in a variety of ways such as by leaching of coating components into the beverage, or by adsorption of flavor by the coating, or sometimes by chemical reaction, or by some combination thereof.
Container coating technology frequently utilizes an epoxy resin which has been grafted with acrylic monomers, styrene, and methacrylic acid. This grafted epoxy resin is prepared in solvent, usually butyl cellosolve, and n-butanol, to maintain low processing viscosities and then reduced with water by a direct or inverse let down procedure. Although cured film properties are highly desirable, such coatings suffer from the fact that sizeable amounts of solvent are required to obtain good performance. High molecular weight epoxy resins typically require 50% to 90% solvent (based on total solids plus organic solvent) before reducing with amine and water.
Epoxy based can coatings comprising a carbon grafted acrylic chain produced in the presence of an extender resin are disclosed in U.S. Pat. No. 4,399,241 and U.S. Pat. No. 4,482,671 while U.S. Pat. No. 4,595,716, and U.S. Pat. No. 5,157,078 teach a carbon grafting process involving solvent polymerization at moderate temperatures with high levels of peroxide initiator to produce a carbon-graft polymer. The high solvent levels, however, invariably carry over to the aqueous dispersion when the resulting polymers are dispersed into water to produce a VOC (volatile organic compounds) level considerably above 2 and typically between 3 and 4 pounds volatile organic compounds per gallon of resin solids.
Commonly assigned U.S. Pat. No. 5,290,828 discloses an acrylic grafted epoxy polyester terpolymer produced by in-situ copolymerization of ethylenic monomers with low molecular weight epoxy and unsaturated polyester resins where carboxyl monomers esterify epoxy groups while monomer double bonds coreact with polyester double bonds to form the terpolymer. Commonly assigned Ser. No. 222,029 filed Apr. 4, 1994 discloses an acrylic grafted epoxy-ester produced by first esterifying epoxy resin with a carboxyl functional unsaturated polyester to form an unsaturated epoxy-ester. The unsaturated epoxy-ester is dispersed into water and followed by in-situ copolymerization of ethylenic monomers in the aqueous dispersion, where the copolymerized monomers partially graft to the preformed unsaturated epoxy-ester.
Coating compositions based on microgels are shown in U.S. Pat. No. 4,897,434 where epoxy esters are preformed, then dispersed into water, and thereafter further crosslink available epoxy and carboxyl groups on the preformed epoxy-ester.
It now has been found that a preformed, carboxyl functional, low molecular weight acrylic addition copolymer of copolymerized ethylenic monomers, including carboxyl functional ethylenic monomer, can be utilized advantageously as an aqueous dispersing or suspending agent for dispersing an epoxy resin into water to produce a very low VOC coating having a VOC (volatile organic compounds) less than about one pound per gallon of resin solids. The resulting water dispersed epoxy resin provides an emulsion polymerization medium, where the addition copolymer dispersing agent is esterified with the epoxy functional resin to form crosslinked microgel particles stably dispersed in water. The acid functional, low molecular weight addition copolymer, preferably an acrylic copolymer, (preferably 2,000 to 20,000 Mn) can be dispersed in ammonia water to form small particle size dispersions (ca 50 nm), while subsequent crosslinking with liquid epoxy resin converts these dispersions to microgels. The water dispersed, crosslinked small particle size provide good storage stability, rheology control, along with exceptional film properties including excellent water resistance, low temperature cure, excellent flexibility, and good resistance to odor adsorption. This invention avoids the use of acid functional polyesters, which can slowly hydrolyze causing gelation while rheology of very low viscosity products can only be controlled by adding rheological control agents. In this invention, the acrylic copolymer dispersant can be synthesized at a very low solvent level (<1 lb/gal VOC), dispersed into ammonia water, and subsequently crosslinked with liquid epoxy resin to form stable microgel particles. Crosslinking of the addition copolymer with diepoxide while stably dispersed in water produces very small size crosslinked microgel particles, a physical property particularly useful for producing tough but resilient coating films applied to a substrate. Further advantages rely on an acid functional acrylic to produce small particle size dispersions (ca. 50 nm) with low applied shear which will not hydrolyze and provide excellent storage stability. Viscosity can be easily controlled by adjusting acrylic Mn, carboxylic acid concentration, comonomer type, and degree of reaction with epoxy resin. These and other advantages of this invention will become more apparent by referring to the detailed description and illustrative examples.


1. Field of the Invention
The present invention relates to a liquid crystal display unit and a method for its production.
In recent years, the display areas of liquid crystal display units of such devices as computer terminals, personal computers, word processors, TVs and the like have become increasingly larger, and their uses are expected to become further expanded in the future, accompanied by greater demand to realize liquid crystal display units with visual angle characteristics equaling those of CRTs (cathode ray tubes).
2. Description of the Related Art
Some techniques have already been proposed for improving viewing angle characteristics, including a PDN type (Polymer Dispersed Liquid Crystal Display with Crossed Nicols; see Japanese Unexamined Patent Publication No. 4-212928), an amorphous TN type (Amorphous Twisted Nematic Liquid Crystal Display; see SID '94 Digest, p. 915-918) and a PTN type (Polymer Twisted Nematic Liquid Crystal Display; see Japanese Unexamined Patent Publication No. 5-27242).
FIGS. 7A and 7B are illustrations of PDN-type liquid crystal display units of the prior art, FIG. 7A showing a state without application of voltage and FIG. 7B showing a state with application of voltage.
In these drawings, 21 is a transparent base plate, 22 is a transparent conductive film, 23 is a transparent base plate, 24 is a transparent conductive film, 25 is a polymer, 26 is a liquid crystal molecule, 27 is a liquid crystal droplet, 28 is a liquid crystal layer, 29 and 30 are polarizer, 31 is a round cushion-shaped film with optical anisotropy, 32 is an alternating current power source and 33 is a switch.
In this conventional PDN-type liquid crystal display unit, the opposing transparent base plate 21 with the transparent conductive film 22 and transparent base plate 23 with the transparent conductive film 24 form a structure sandwiching the liquid crystal layer 28 containing the polymer 25 and liquid crystal droplets 27. Also, the pair of polarizers 29 and 30 whose directions of polarization are orthogonal are laid over the outside of the transparent base plates 21 and 23.
A round cushion-shaped film 31 with optical anisotropy, such as a polycarbonate polyaxially stretched film, is laid between the transparent base plate 23 and the polarizer 30 on the display side.
The alternating current power source 32 and the switch 33 are connected in series between the transparent conductive film 22 and the transparent conductive film 24.
In this liquid crystal display unit, when no voltage is applied from the alternating current power source 32 between the transparent conductive films 22 and 24, the liquid crystal molecules 26 in each of the liquid crystal droplets 27 are controlled so as to line up at the interface with the polymer 25, but since the orientation of the liquid crystal molecules 26 on the liquid crystal droplets 27 is unordered, incident light 34 from the back side is scattered by the liquid crystal molecules 26 and passes through the polarizing plate 30 appearing milky white, and bright (see FIG. 7A).
When a voltage is applied from the alternating current power source 32 between the transparent conductive films 22 and 24, the liquid crystal molecules 26 in the liquid crystal droplets 27 align in the direction of the electric field, and as a result light scattering is reduced and incident light 34 from the back side may pass through the liquid crystal layer 28 unhindered.
However, since the polarizers 29 and 30 are arranged in crossed Nicols, the light cannot pass through the polarizer 30, giving a dark appearance.
When the liquid crystal panel of this liquid crystal display unit is viewed at an oblique inclination angle, the liquid crystal molecules 26 and the incident light 34 both are viewed from an oblique inclined angle and the optical effect of the liquid crystal layer 28 appears to some degree causing light leakage, and therefore the round cushion-shaped film 31 with optical anisotropy is inserted to block the resulting leaking light which passes through the polarizing plate 30.
Generally speaking, when the refractive index of a liquid crystal molecule is expressed in three-dimensional terms it may be compared to a rugby ball-shaped index ellipsoid, and the refractive index when viewed at an oblique inclination angle corresponds to the ellipse section resulting from cutting the rugby ball-shaped index ellipsoid at an oblique inclination angle.
On the other hand, when the refractive index of a molecule of the round cushion-shaped film with optical anisotropy is expressed in three-dimensional terms, it exhibits the characteristics of a round cushion-shaped index ellipsoid, and the refractive index thereof when viewed at an oblique inclination angle corresponds to the ellipse section resulting from cutting the round cushion at an oblique inclination angle.
Also, the ellipse section resulting from cutting the rugby ball-shaped index ellipsoid of the liquid crystal molecule at an oblique inclination angle and the ellipse section resulting from cutting the index ellipsoid of the round cushion-shaped film with optical anisotropy at an oblique inclination angle have their long axes and short axes rotated 90.degree. to each other.
Consequently, when the ellipse section resulting from cutting the rugby ball-shaped index ellipsoid of the liquid crystal molecule at an oblique inclination angle and the ellipse section resulting from cutting the index ellipsoid of the round cushion-shaped film with optical anisotropy at an oblique inclination angle are superimposed a circle results, and the optical effect is canceled out.
Therefore, as mentioned above, the superimposition of the round cushion-shaped film 31 with optical anisotropy cancels out the effect of the inclined incident light, and therefore the black display produced when a voltage is applied between the electrodes has a consistently dark appearance even when viewed from an oblique inclination angle, giving a constant display when viewed from any direction, and producing the effect of a wider visual angle.
FIGS. 8-A-1 to 8-A-4 and 8-B-1 to 8-B-4 are illustrations of amorphous TN-type liquid crystal display units of the prior art, FIGS. 8-A-1 to 8-A-4 showing the prior art and FIGS. 8-B-1 to 8-B-4 showing amorphous TN-type liquid crystal display units.
In these drawings, 41 is a first transparent conductive base plate, 42 is a second transparent conductive base plate, 43 and 44 are alignment films, 45 is a liquid crystal molecule, 46 is a liquid crystal layer and 47 and 48 are non-rubbed polymer films.
A prior art TN (Twisted-nematic) liquid crystal display unit with rubbed alignment films will now be explained with reference to FIGS. 8-A-1 to 8-A-4.
In this TN liquid crystal display unit of the prior art, the liquid crystal layer 46 comprised of liquid crystal molecules 45 is sandwiched between the first transparent conductive base plate 41 with an alignment film 43 which is rubbed in the direction perpendicular to the plane of the paper, and the second transparent conductive base plate 42 with an alignment film 44 which is rubbed left to right on the plane of the paper.
In this TN liquid crystal display unit, even at clearing temperatures at which the orientation of the liquid crystal molecules 45 is random (isotropic), the liquid crystal molecules 45 contacting with the alignment films 43 and 44 of the first transparent conductive base plate 41 and the second transparent conductive base plate 42 which are rubbed in orthogonal directions are aligned in these respective directions of alignment by the restraint of the alignment films 43 and 44 (see FIG. 8-A-1).
When the temperature is lowered below the clearing temperature, the effect of the liquid crystal molecules 45 contacting with the upper and lower alignment films 43 and 44 reaches inside the liquid crystal layer 46, and a column of liquid crystal molecules 45 begins to grow (see FIG. 8-A-2).
When the temperature is further lowered, the effect of the liquid crystal molecules 45 contacting with the upper and lower alignment films 43 and 44 reaches further inside the liquid crystal layer 46, and the column of liquid crystal molecules 45 grows larger (see FIG. 8-A-3).
When the temperature is even further lowered, the effect of the liquid crystal molecules 45 contacting with the upper and lower alignment films 43 and 44 reaches even further inside the liquid crystal layer 46, and the column of liquid crystal molecules 45 is completely formed between the upper and lower alignment films 43 and 44. Since the twist origins of the liquid crystal molecules 45 are the same in state, the viewing angle characteristics are narrower (see FIG. 8-A-4).
An amorphous TN-type liquid crystal display unit will now be explained with reference to FIGS. 8-B-1 to 8-B-4.
In this amorphous TN-type liquid crystal display unit, the liquid crystal layer 46 comprising liquid crystal molecules 45 is sandwiched between a first transparent conductive base plate 41 and a second transparent base plate 42 with non-rubbed polymer (polyimide PI) films 47 and 48.
In this amorphous TN-type liquid crystal display unit, at clearing temperatures at which the orientation of the liquid crystal molecules 45 is random, the surfaces of the non-rubbed polymer films 47 and 48 in contact with the liquid crystal molecules 45 are rough, and therefore the liquid crystal molecules 45 are not aligned, being oriented in random directions (see FIG. 8-B-1).
When the temperature is further lowered, a column of aligned liquid crystal molecules 45 does not grow from the surface of the liquid crystal layer 46 in contact with the non-rubbed polymer films 47 and 48, but rather grows from the interior (bulk region) (see FIG. 8-B-2).
When the temperature is even further lowered, the alignment of the liquid crystal molecules 45 occurring in the bulk region is promoted, causing the column of liquid crystal molecules 45 to grow larger (see FIG. 8-B-3).
When the temperature is still further lowered and a temperature of 30.degree. C. below the clearing temperature is maintained, the alignment of the liquid crystal molecules occurring in the bulk region is further promoted, and the column of liquid crystal molecules 45 in each region is completed between the non-rubbed polymer films 47 and 48, with the liquid crystal molecules 45 becoming rigidly fixed in that state (memory effect).
In this state, the twist origins of the liquid crystal molecules 45 in contact with the surfaces of the non-rubbed polymer films 47 and 48 are random, and therefore the viewing angle characteristics of each of the columns of liquid crystal molecules 45 are averaged to provide improved viewing angle characteristics and to obtain a gray scale (see FIG. 8-B-4).
FIG. 9 is an illustration of a PTN-type liquid crystal display unit of the prior art.
In this drawing, 51 and 52 are transparent conductive base plates, 53 denotes liquid crystal molecules, and 54 denotes a material which disturbs the twisted arrangement of the liquid crystal molecules.
In this conventional PTN-type liquid crystal display unit, liquid crystals such as cholesteric liquid crystals or chiral nematic liquid crystals are injected between the pair of transparent conductive base plates 51 and 52 with transparent electrodes and alignment films on their opposing inner sides, and there is also injected a material 54 to disturb the twisted arrangement of the liquid crystal molecules, for example an organic polymer such as polymethyl methacrylate, polystyrene melamine resin, urea resin, phenol resin or polydiisopropyl fumarate, or a photopolymerized polymer such as polyurethane acrylate, polyester acrylate, epoxy acrylate or polyether acrylate, in order to change the arrangement of the liquid crystal molecules 53.
As a result, the twisted orientations of the liquid crystal molecules along the lines A, B and C vary slightly depending on the position of the liquid crystal layer, even with the same viewing angle direction.
Since the twisted orientations of the liquid crystal molecules 53 vary slightly along the lines A, B and C in this drawing, application of a voltage causes the liquid crystal molecules 53 to be aligned differently, and the orientations of the liquid crystal molecules 53 are averaged with respect to the viewing angle direction, thus resulting in averaging of the apparent transmittance/applied voltage characteristics, improved viewing angle characteristics, and suppression of the abnormal display inversion phenomenon.
In the PDN-type liquid crystal display unit described above it has not been possible to impart optical activity to the liquid crystal molecules, and consequently the display brightness of displayed white has been only 1/3 that of TN-types.
In addition, the sizes of the domains lack uniformity in amorphous TN-type liquid crystal display units and are large, and when the display surface is viewed from an oblique inclination angle a patchy black and white pattern is produced.
When the display surface is viewed from an oblique inclination angle, the black portions and white portions are of an extremely small identical size and there are few problems so long as they are dispersed, but since the domains are large, they appear as patches.
This condition is the same in the case of PTN-type liquid crystal display units, which have had the problem of patchiness when viewed from an oblique inclination angle.
It is an object of the present invention to provide a liquid crystal display unit with satisfactory viewing angle characteristics and which eliminates such patches when viewed from an oblique inclination angle.


Transactions are familiar to us in everyday life when we exchange money for goods and services, such as buying a train ticket or paying for medicine. Such transactions involve a short conversation (for example, requesting availability and cost), and then making the payment. The processing of any one of these items is a business transaction of the kind that is handled by a transaction management system.
A transaction in the business sense can be viewed as an activity that must be completed in its entirety with a mutually agreed-upon outcome. It usually involves operations on some shared resources and results in overall change of state affecting some or all of those resources. When an activity or a transaction has been started and the mutually agreed outcome cannot be achieved, all parties involved in a transaction should revert to the state they were in before its initiation. In other words, all operations should be undone as if they had never taken place.
There are many examples of business transactions. A common one involves transfer of money between bank accounts. In this scenario, a business transaction would be a two-step process involving subtraction (debit) from one account and addition (credit) to another account. Both operations are part of the same transaction and both must succeed in order to complete the transaction. If one of these operations fails, the account balances must be restored to their original states.
Typically such transactions consist of many computing and data access tasks to be executed in one or more machines; the tasks may include handling the user interface, data retrieval and modification, and communications. In the example above, the money transfer operation is a transaction composed of debiting one account and crediting another.
In the context of business software, we can express the above more precisely. A transaction (sometimes also referred to as a ‘Unit-Of-Work’ or ‘UOW’) is a set of related operations that must be completed together. All their recoverable actions must either complete successfully or not at all. This property of a transaction is referred to as ‘atomicity’.
In the simplest case, a transaction will access resources connected to a single computer processor. Such a transaction is referred to as a ‘local transaction’. More often, however, a transaction will access resources which are located in several different computer processors, or logical partitions, each maintaining its own transaction log. Such a transaction is referred to as a ‘distributed transaction’.
When a distributed transaction ends, the atomicity property of transactions requires that either all of the processors involved commit the transaction or all of them abort the transaction. To achieve this one of the processors takes on the role of coordinator to ensure the same outcome at all of the parties to the transaction, using a ‘coordination protocol’ that is commonly understood and followed by all the parties involved. The two-phase commit protocol has been widely adopted as the protocol of choice in the distributed transaction management environment. This protocol guarantees that the work is either successfully completed by all its participants or not performed at all, with any data modifications being either committed together (completed) or rolled back (backed out) together on failure.
Another property of a transaction is its durability. This means that once a user has been notified of success, a transaction's outcome must persist, and not be undone, even when there is a system failure. A recovery manager is used to ensure that a system's objects are durable and that the effects of transactions are atomic even when the system crashes. The recovery manager saves information required for recovery purposes. This recovery can be for the dynamic backout of a transaction, perhaps as a result of a failure after a task updated a recoverable temporary storage queue. Additionally the recovery data can be used for restoring a transaction processing system to a committed state, for example when the system is restarted after system failure. Typically, the recovery file comprises at least one log containing the history of the transactions performed by a transaction processing system. In the event of a system failure, the recovery file can be played back to return the system to its state right before the failure, and the transaction log(s) used to check for and undo transactions that were not properly completed before failure.
Also, in the event of a transaction failure, the transaction log can be used to reverse updates that have been carried out by that transaction, by working backwards from the last change before the failure, hence the name ‘dynamic transaction backout’. The backout occurs before any locks on any affected resources are released, which safeguards other tasks from the possibility of using corrupted data, because modified data is not released for use by them (“committed”) until the current task has finished with it. In case the log needs to be replayed later in a system restart, an entry is first made in the log to indicate that that transaction is being backed out.
Examples of systems which carry out such transaction logging include transaction systems such as IBM® CICS® Transaction Server or IBM WebSphere® Application Server, as well as database systems such as IBM DB2® or IBM IMS™ (IBM, CICS, WebSphere, DB2 and IMS are trade marks of International Business Machines Corporation).
The scheduling and dispatching of transaction processing tasks is usually handled by a dispatcher, which controls the order in which tasks are handled by allocating processor time among them, based on a dispatching priority value associated with each task. The log typically records the information in the order that the activity occurs. Without some management, this would consume an ever increasing amount of resource. So it must be reorganised on a regular basis so as to reduce its size by the recovery manager carrying out a process called ‘keypointing’. Keypointing comprises writing current committed values of a system's objects to a new portion of the recovery file, together with transaction status entries and intentions lists for transactions that have not been fully resolved. An intentions list for a transaction contains a list of the references and the values of all the objects/resources that are altered by that transaction, as well as information related to the two-phase commit protocol. Once a keypoint has been taken, i.e. information stored through a keypointing procedure, recovery information for irrevocably committed (or backed out) transactions can usually be discarded from the log, sometimes called ‘trimming’ the log. This reduces the file size of the log as well as the number of transactions to be dealt with during recovery.
The rate that old log records are deleted by trimming should ideally match the rate at which new log data is being generated as new work enters the transaction system and makes its own recoverable changes to resources. In a well tuned on-line transaction processing (OLTP) environment, the volume of log data held on the log should remain reasonably constant over time, with an underlying periodic rise and fall in the number of log records held on the log as both the new work and the housekeeping work are performed.
This mechanism of log data deletion usually solves the problem of logs continually growing in size over time. However, a long-running UOW can prevent this mechanism from working, as until such a UOW has completed, and its log data is no longer required, its data cannot be deleted from the log and all data logged since the first log entry of that UOW must be maintained on the log. Hence, the system will not be able to trim the log after keypointing, and the log will grow and grow in size. A long-running unit of work (UOW) of this type may be a valid UOW that has performed a large number of recoverable changes, and so generated a large volume of log data. Alternatively, it may be for a so-called ‘rogue’ program that has entered an invalid loop while performing continual recoverable changes, thereby generating an excessive number of log records, or which is hanging in an uncommitted state.
Eventually, when a critical threshold of the logging subsystem, the operating system, or the available hardware is exceeded, a request to write to the log will fail for an “out of space” type of condition. When such an error is returned to the transaction system, it typically results in a serious failure. The system can no longer log any recoverable changes and so protect them from failures that require them to be backed out. Recovery processing (and hence data integrity) can no longer be guaranteed.
Current mechanisms intended to prevent such a scenario include the emission of human-readable messages when a certain number of keypoints have been taken without the system having been able to trim the log. Such messages typically indicate the UOW which is preventing the log from being trimmed. In response to such a message, or to a series of such messages, a system operator may choose to take manual action to terminate that ‘rogue’ UOW.
The present invention seeks to address the above problems and provide an improved mechanism which may reduce the likelihood of encountering a log-full condition.


The invention relates to a system for inspecting and/or processing a sample on a stage with a probe or imaging apparatus.
High resolution lithography and micro-machining tools (e.g. E-beam lithography system, DUV-stepper), inspection and process-control equipment (e.g. CD-SEM, defect location and defect review tools) and analytical and test equipment (SEM, FIB, AFM, high resolution tools using UV, DUV, and EUV light sources) require stages for carrying and moving the sample to be inspected and/or processed.
With increasing resolution requirements of those systems, the demands on these stages with respect to stability and position accuracy are steadily increasing. Accuracy and stability requirements are below 100 nanometer and will probably go down below 1 nanometer. The mechanical design and mechanics of the stage no longer can fulfill the challenging demand alone. Therefore, it is necessary to apply position control means to support the stage position accuracy and stage stability.
Stage position control is performed mainly by two tools, by a linear optical encoder and by a laser-interferometer. A linear encoder consists of optical grids or gratings which are connected to the stage and whose motion is read by suitable optical sensors, which are placed on the non-moveable part of the stage setup. The laser-interferometer control uses the interference between a reflected beam, which is generated by a mirror connected with the stage, and a reference beam. Since the wavelength of the laser beam is used as a measurement unit, laser interferometers offer a much better position accuracy (in the range of 10 nm) than optical encoders which have an accuracy in the range of 100 nm.
Linear encoders have the drawback that their accuracy is limited. Laser-interferometers are much more accurate, but they are very complex and expensive. The accuracy is limited by changes in the refractive index of the optical light path and the quality of the mirrors. Furthermore, laser-interferometers are used preferably for x-y-coordinate measurements. Setups for a 3-dimensional coordinate measurement of stage position is very difficult to realize.
From EP-A-0 559 402 and U.S. Pat. No. 3,936,716 stabilization systems are known for stabilizing a platform with gyroscopic means.
It is an object of the invention to provide a system for inspecting and/or processing a sample on a stage with a probe or imaging apparatus with a precise, simple and cost-effective position control means.
It is a further object of the invention to provide means which allows both the accurate control of the position of the stage relatively to the probe or imaging apparatus and the mechanical detection and stabilization of mechanical disturbances (e.g. vibrations, drift).
The position control means can be preferably used in probe systems (particle beam systems, atomic force microscopes, high resolution tools).
The gyroscopic means is adapted to measure movements in one, two or three dimensions.
In a preferred embodiment, there is at least one motor for moving the stage and/or the probe or imaging apparatus which is operatively connected with the position control means.
The system for inspecting and/or processing a sample according to a preferred embodiment comprises a probe or imaging apparatus. The probe and/or imaging apparatus according to the disclosed embodiment is defined by a scanning probe or a column with beam generating means and means to deflect the beam. In case of a column, the column is equipped with column gyroscopic means to detect movements of the optical column. Furthermore, the control means is operatively connected with the deflection means in order to compensate uncontrolled movements (vibrations, drift) of the stage relatively to the column.
In another system for inspecting and/or processing a sample, the probe or imaging apparatus is defined by an optical column having beam generating means, means to deflect the beam and image generating means wherein the control means is operatively connected with the image generating means in which the unintentional movements of stage relative to the column will be taken into account when processing the image.


The invention concerns a method and an apparatus which is especially advantageous for its performance in the thermal longitudinal parting of rectangular metal plates, in particular of cut-to-length continuous casting plate slabs while the metal plates rest on supports which run crosswise to the longitudinal direction of the parting. In the cross-parting of steel, cast as a continuous slab, or of NE-metals, the thermal separation on the basis of oxygen-flame cutting or plasma-flame cutting serves the preparation for the rolling which follows, whereby the cross-parting determines the length of, for instance, the coil weight of the tin sheeting to be rolled. Compared with that, the conditions, when parting metal slabs longitudinally, present themselves differently because in the latter case the desired width of the tin sheeting to be rolled out is determined. In recent years the aim was to increase the production rate in continuous casting through increasing the batch weights and through larger slab widths. Wider slabs do allow for a more economical production of casting products under maximal exploitation of the slab-casting apparatus. However, the wider slabs must be reduced to existing first-pass cross sections of the rolling mills, the width dimensions of which in turn go necessarily by the widths of the tin sheeting which are required in the subsequent procedure.
It is well-known (DE-AS No. 27 10 564) how, in order to fulfill this requirement, to move the cutting arc relative to the plate slab when parting crosswise, in which case, according to this suggestion vis-a-vis parting lengthwise the only difference is that the plate slab is at rest. The well-known longitudinal parting procedure requires, however, special steps for the protection of the supports which pass in crosswise direction to the longitudinal parting direction. Therefore, a diversified formation is required of the existing supports which go crosswise to the longitudinal parting direction. At first, individually driven rolls cause the transportation of the plate slabs. These rolls must be able to swing out in order not to be destroyed during the flame cutting. Further, crosswise-passing rigid plate slabs are provided which have to have so-called burn point openings for the path of the cutting arc. The burn point openings which are arranged in the path of the cutting arc result in a slit-like burn canal, the length of which corresponds to the length of the plate slabs, for instance 8 m and more, turns out to be very extended. A further disadvantage is that the slag and an increased amount of gas must be carried away from the long burn canal. Besides, the burning canal is firmly built-in and does not allow for any adjustment to changing the widths of the plate slabs to be parted longitudinally.
The invention is based on the task to simplify the known method, and based on that to create a better protected apparatus with less expenditure.
This task is solved in accordance with the invention by moving the metal slabs in longitudinal parting direction vis-a-vis the cutting arc which is motionless in the longitudinal parting direction and which is in a given case movable crosswise to the longitudinal parting direction only because of corrections in width conditional on deviations in width or through skewed position of the metal slabs, and by carrying off between two supports the slag collected at some point crosswise to the longitudinal parting direction between two supports. This proposal follows neither the principle of crosswise parting, in which case the continuously cast slab is moved by the pouring velocity which is followed by the cutting arc, nor does it follow the known principle where the continuous-cast plate slab is at rest. Consequently, it is advantageous that neither swing-away support rolls nor a relatively long burn-canal are necessary but that a burn-canal results naturally between the two existing support rolls. Accordingly, the burn-canal is short and the collected burn slag may be removed via a short passage. Furthermore, there is a resultant decrease in the volume of gas-exhaust and accordingly less power for the drive of the gas-exhaust. Another advantage of the invention lies in the fact that heavy crosswise-slidable slab centering machines are avoided, which are replaced by control arrangements which move the much lighter cutting arc installations. A further advantage lies in the possibility of changing the width-program without displacing the burn-point openings, i.e., to insert partings of 1/2, 1/3, 1/4 and the like for short runs.
An increased cutting performance may now be achieved after a further improvement of the invention, in that at least two metal slabs are moved relative to motionless cutting arcs which are at any given time spaced in the longitudinal parting direction. The doubling of the cutting capacity leads to an increased yield in cut goods and to an increased performance in comparison with cutting machines which run counter and thereby necessarily impede each other on encounter.
The performance of longitudinal parting is increased by an additional proposal in method when at a given time a metal slab is being cut only partially in the longitudinal direction, the cutting arc switched off afterwards, and this same metal slab is completely parted under a cutting arc which is pre-positioned in the longitudinal parting direction at a distance of more than the length of a slab, while the following metal slab is again parted, in longitudinal direction, only partially with the cutting arc again switched on.
The apparatus for the application of the invented method is designed in such a way that a cutting arc is provided between two rigidly arranged roller-bed rolls supporting the metal slabs along their full width. The cutting machine is motionless in the longitudinal parting direction and may be adjusted crosswise to the longitudinal parting direction. A pair of driving rolls are mounted adjacent the cutting machine. A conveyor duct for the resultant slag is provided, arranged crosswise to the longitudinal parting direction under the cutting machine, and a gas-exhaust pipe is connected to the conveyor duct. No swing-away rolls or additional supports are needed. The cutting machine, which is only movable crosswise, needs simpler electric conductors and conductors for the means of cutting. In view of the width of the slab, the conveyor duct has relatively short dimensions and requires a smaller intake of energy. The exhauster performance of the gas-exhaust pipe is also less.
The transport of the uncut metal slabs, as well as the pieces cut and longitudinally parted, causes no problem, in that two cutting machines are tandem-joined, with a distance between the longitudinal parting direction at least as large as the maximal length of a metal slab.
A pair of driving rolls is positioned in front of the first cutting machine and a second pair of driving rolls is positioned behind the second cutting machine in longitudinal parting direction. The distance between the first cutting machine and its respective pair of driving rolls is at any time smaller than the uncut length of a minimal metal slab length while the distance between the second cutting machine and its respective pair of driving rolls is smaller than the cut length of a minimal slab after leaving the first cutting machine.
The crosswise movability required for the lateral corrections of the cutting machine may be used for an additional function, in that the cutting machine is adjustable crosswise to the longitudinal parting direction to provide for various parting widths of the cut slabs.
In addition, the short length of the slag conveyor path advantageously permits the conveyor duct to consist of a vibrating chute. To allow for lateral correction, as well as adjustment for various parting widths, lateral tracing devices are provided for tracing the vertical sides of the metal slabs which determine their width. The cutting machine is arranged to be motionless in the longitudinal parting direction, and the control of the crosswise drive of the cutting arc is geared towards an even distribution of the deviations onto the width of the pieces parted longitudinally.
While the long cutting path on cutting machines which are moved in cutting (transverse) direction require increased input for sound containment, the invention permits the cutting machine, which is stationary in longitudinal parting direction, to be arranged in a soundproof casing corresponding to the size of the cutting machine. The invention also avoids movable attachments and provides a rigid striker bar on at least one side of the roller bed at the level of the metal plate bar thickness.
A high cutting peformance is attained while using less space when several longitudinal parting paths are arranged parallel next to each other, connected via a device pulling in transversal direction.
An example embodiment is shown in the drawing and is described in more detail below.


A Transmission Control Protocol/Internet Protocol (TCP/IP) packet is a relatively commonly used packet. In order to increase an uplink capacity and improve user data transmission efficiency, compression processing needs to be performed on the TCP/IP packet in a transmission process. In the prior art, a header compression manner is used for a TCP/IP packet, that is, compression is performed on a header of the TCP/IP packet. In the header compression manner, if headers of multiple TCP/IP packets vary little and have high repeatability, compression on the headers of the multiple TCP/IP packets in the header compression manner may improve data transmission efficiency and save a network resource.
In a data transmission process, in addition to header information of the TCP/IP packet, a packet at an application layer above a TCP/IP layer also has similar content, so that compression may be further performed, so as to increase a transmission capacity. However, compression of application layer data is not implemented in the prior art.


As our daily activities become ever more reliant on access to and interaction with various web services, a growing problem facing a typical end user is that of the ability to streamline and optimize cross-device updates and events originated by web services. A particular challenge is to effectively monitor and navigate to and through the multiple services to which an end user has subscribed to use the desired feature or to access a given update or event. Web with Real Time Communication (WebRTC) services need to notify users and connect sessions, news services alert for news events, sports services alerts for sport scores, stock services alert for stock prices. The assumption of all of these services is that the user has exactly one device that needs to be alerted or, if the user has more than one device, the user will define alerts for each device at the service level. Some notifications need the user to have an active session (e.g. WebRTC). For some devices that get different Internet Protocol (IP) addresses each time they join the network (e.g. laptops), registrations are needed every time a new network address is acquired. Some notifications are sent to persistent addresses (e.g. mailboxes), and others are sent to a device identity whose IP address may change but the network resolves the identity (e.g. smartphones).
For many services that require the ability to connect two users together in real-time, the service is based on the user maintaining current registrations with the service.
Today, most users have multiple networked devices (laptop, smartphone, tablet, etc.,) that may be used at different times. Some of those devices may be shared among several people (e.g. family members) and notifications should come to those devices only when the right individual is using the device. For example, suppose that Grace is a doctor who is on call for consultations from ten separate practices which use separate web-based services to communicate with medical professionals. Each of the services may have a separate unique login and password for Grace. When Grace logs onto the network from any device in the morning, she wants to be connected to all ten services from a single device. If Grace switches from her laptop at home to her cell phone and then to her laptop at work, she may want to inform all ten services to contact her to her work laptop. If Grace has multiple devices registered to all ten services simultaneously, she may want to be able to either have all the devices be informed of incoming messages, or to designate certain devices to communicate with certain services. However, no existing systems provide Grace with a centralized control over the relationship between a plurality of her devices and a plurality of services in the manner described in this example.


To meet rapid progress of industrial development machining techniques also advance constantly to produce finer finished or semi-finished products. The fabrication precision of machinery depends on many factors, such as precision of tools, operation precision of the machinery, fabrication environment, and coupling and holding steadiness of the machinery and tools. One set of machine usually can hold different types of tools alternately to achieve different fabrication results (such as by changing the tools of varying sizes). After each tool changing, a calibration procedure has to be performed (because movements occur during tool changing). This involves a tedious process. Both the chuck and tool have to be removed from the machine and installed again. Fabrication tolerances and errors are bound to happen. To remedy this problem, many techniques have been proposed in prior art. For instance, R.O.C. patent No. M253434 entitled “Detachable chuck” discloses a structure mainly including a cutter stem with an axial conical cavity extended inwards from one end in a tapered manner, a holding member with a conical portion at one end and a coupling portion at the other end and a fastening member coupled on the holding member from outside and screwed on the cutter stem. The conical portion has an inclined peripheral surface formed at an angle the same as that of the conical cavity of the cutter stem, and is held in the conical cavity. The coupling portion has a central hole to hold a cutter under heating. Due to the cutter is held under heating, replacement of the cutter is troublesome. There are still rooms for improvement.