The breath test distinguished between women with breast cancer and healthy volunteers with a sensitivity of 94.1% (48/51) and a specificity of 73.8% (31/42) using these eight VOCs. Using five other breast cancer biomarker VOCs, the breath test distinguished between women with breast cancer and healthy volunteers with a sensitivity of 93.8% and a specificity of 84.6%. Those five VOCs are 2-propanol, 2,3-dihydro-1-phenyl-4(1H) quinazolinone, 1-phenylethanone, heptanal, and isopropyl myristate [18]. According to the trapping capability of gas, we choose the following sorbents: Carbopack?B and Tenax? GR, adopt OD1/4 inch, 7-inch length standard sorbent tube, and filling with 120-150 mm (about 600~1,000 mg) mixed sorbents, which can complete the sampling of object gas.
The multi-bed sorbent tube is shown in Figure 2.
The tube consists of 60 mm Tenax? GR plus 60 mm of Carbopack?B separated by 3 mm of glass wool. These adsorbents are arranged in order of increasing sorbent strength from the sampling end of the tube. During the filling process, the sorbents should not be too tight to stress the sorbents or too loose to leave holes at the sorbent bed.Figure 2.Multi-be
Two kinds of well-known distinct methods for the observation of white light interferometric fringe patterns in optical fiber sensor systems are spectral domain processing and phase domain processing [4]. Phase domain processing method can be further divided into two classes, depending on the method of pattern formation, namely temporal fringe formation and spatial fringe formation.
In the Anacetrapib spectral domain processing, a spectrum analyzer is used to directly process the output of sensing interferometer with a spectral resolution capability of ���� [nm Cilengitide ]. Any temperature change affecting the sensing interferometer induces a change in modulation frequency of the measurement signal and the position of maxima (fringe peaks) in the spectral pattern as well, which can be measured and mapped to the temperature. Reference [5] proposed a WLI temperature sensor system where a low finesse reflective mode Fabry-Perot interferometer is used as a sensing interferometer and an optical spectrum analyzer is used as a processing unit. This WLI system attained (absolute) temperature measurement over the range from 298K to 673K with resolution equal to 1 K, but, the relation between temperature and modulation frequency (fringe spacing of the spectrum of output of sensing interferometer) was not quite linear and it is questionable to apply the result for absolute temperature measurement.