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901.
Based on the configuration of surface plasmon resonance (SPR) sensor, the SPR sensor model is set up, and the thermo-properties of various parts in the model are discussed. The thermocharacteristics of SPR spectra in wavelength interrogation and angular interrogation are investigated. Results show that thermo-optic and dispersion effects in the model deteriorate the sensitivity of SPR sensor, especially the thermooptic effects. Mathematical expression is established to describe the resonance wavelength or angle, which is dependent of temperature. It demonstrates that the thermo-property of sensing medium excites the fluctuation of resonance wavelength or angle more intensely than that of the substrate or metal film in 1-2 orders. Our theoretical research is consistent with the previous experimental results. 相似文献
902.
903.
This paper considers the problem of non-Newtonian oil displa-cement by water in porous media.adopting the linear permea-tion law with initial pressure gradient.For one-dimensionalflow,the basic equation of non-Newtonian oil displacement bywater in sandstone reservoirs and fractured reservoirs is de-rived and numerical solutions are obtained.The results arecompared with the corresponding ones for Newtonian oil dis-placement to show the essential characteristics of non-Newto-nian oil displacement by water. 相似文献
904.
One of the instruments onboard the China Seismic Electromagnetic Satellite (CSES) is the Low Energy Particle Detector (LEPD). The primary objective of LEPD is to provide measurements of the fluxes, energy spectra and pitch angles of 100 keV to 10 MeV electrons and protons from 2 to 50 MeV in the Earth's magnetosphere. The geometric factor is one of the principle parameters of a detector, which converts the physical quantity-count rate to the particle quantity-flux. In this paper, we calculated the geometric factor of LEPD via computer modeling of an isotropic radiation environment. It was first demonstrated that the radiation intensity related should obey a cosine-law, then a general sampling method of generating this distribution via GPS of GEANT4 was explained. Furthermore, combined with flux normalization, a comparison of the geometric factor calculation of a set of 2-layer detectors with different shapes (cylinder, truncated cone and rectangle) was performed. Results show a generally good agreement between simulation and analytical calculations for the cylinder and truncated cone detectors, and the result of the rectangular one, for which there is no accurate analytical formula, is consistent with the previous simulated results by others. As a practical instance of the 2-layer rectangle detector, the geometric factor of LEPD is 10.336±0.036 m cm2·sr for 10 MeV proton and 8.211±0.032 m cm2·sr for 8 MeV electron. 相似文献
905.
906.
高灵敏宽温区吸附热测定装置的建立 总被引:1,自引:0,他引:1
描述了一个适于气/固体系的宽温区、高灵敏的微分吸附热测定装置.在该装置中,吸附放热由Setaram公司热流式微量热量计测定,吸附量由MKS公司电容式压力传感器测定.此外,设计、制作了可在高真空和宽温区内进行吸附热测定的试样池以及对高活泼金属催化剂进行预处理的试样处理池.用标准物质对热量计进行了标定.为验证该装置对吸附热测定的可靠性,测定了H2在Pt/SiO2和γ-Mo2N上的吸附热,所得结果与文献值一致.数据的误差分析结果表明,吸附热测定的相对误差在4%以内. 相似文献
907.
黄芩甙的线性扫描伏安法测定研究 总被引:1,自引:0,他引:1
研究了黄芩甙在多壁碳纳米管修饰电极上的伏安行为。结果表明 ,该修饰电极对黄芩甙产生较强的吸附催化作用 ,催化电流与黄芩甙浓度在 1 .0× 1 0 - 7~ 6.0×1 0 - 5mol·L- 1范围内呈线性关系。利用本法测定了中药黄芩中的黄芩甙的含量 ,效果良好 相似文献
908.
909.
毛细管气相色谱法测定油田水中短链有机酸 总被引:7,自引:0,他引:7
The evaporation of water phase has been used to remove a vast amount of inorganic salts and interferingorganic components. The distillate concentrated by rotary evaporator was directly analyzed by means of wide-bore capillary GC column, The coefficients of variation for C_2~C_5 organic acids were 1.9~6.4%. The recov-eries of the acids in the oilfield water were 81.0~106%. 相似文献
910.