  The attenuation length measuring device was constructed by using oscilloscope
and LabVIEW for signal acquisition and processing. The performance of the
device has been tested with a variety of ways, the test results show that the
set-up has a good stability and high precision (sigma/mean reached 0.4
percent). Besides, the accuracy of the measurement system will decrease by
about 17 percent if a filter is used. The attenuation length of
gadolinium-loaded liquid scintillator (Gd-LS) was measured as 15.10 plus or
minus 0.35 m where Gd-LS was heavily used in Daya Bay Neutrino Experiment. In
addition, one method based on the Beer-Lambert law was proposed to investigate
the reliability of the measurement device, the R-square reached 0.9995.
Moreover, three purification methods for Linear Alkyl Benzene (LAB) production
were compared in the experiment.
