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11.
Ricardo Garcia-Padron Dan Loyd Stefan Sjökvist 《Subsurface Sensing Technologies and Applications》2002,3(2):125-150
One promising method of locating buried objects, such as land mines, is to use optical systems for detecting contrasts in surface temperature. With enhanced knowledge about the interacting physical processes behind these temperature contrasts, it is possible to improve detection precision. In such a context, moisture movement in the soil and moisture evaporation from the surface have been found to be of particular interest. This study was based on indoor experiments on wet and dry sand exposed to radiation from a solar panel. Simulations of heat and moisture transfer conducted with a one-dimensional model are also presented for the experiments. The calculations were successful in accurately predicting surface temperatures for both wet and dry sand, making it possible to predict surface temperatures under different conditions. These findings will contribute to increasing the probability of successful detection of buried objects under real conditions using optical methods. 相似文献
12.
IR2172是国际整流器公司推出的电流传感芯片。介绍了IR2172的结构特点和工作原理以及在永磁同步电机数字控制系统中的应用。 相似文献
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The grafting of acrylic acid onto electron beam‐irradiated polypropylene was carried out using preirradiation method. The stability of peroxy radicals was investigated by electron spin resonance. It was found that the decay of peroxy radicals is much faster at 70°C than at 40°C and ambient temperature. The grafting has been observed to be strongly dependent on the monomer dilution in the reaction medium. The grafting was ascertained by attenuated total reflectance (ATR). The distribution of grafts across the samples was monitored by infrared microscopy. It was found that the graft management is considerably influenced by composition of the grafting medium. The grafting involving pure monomer leads to the surface enrichment with the polyacrylic acid chains. The samples grafted in pure monomer led to much lower contact angles as compared to the diluted monomer solution. The swelling of the grafted samples also showed a trend that was governed by the graft management. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 546–553, 2006 相似文献
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红外目标模拟器校准系统的研制与应用 总被引:1,自引:0,他引:1
采用标准辐射和红外目标模拟器的辐射交替折转进入红外光谱辐射计的方法,研制的红外目标模拟器校准系统可以对红外目标模拟器进行直接校准.该系统由标准准直辐射源,光束偏转装置和红外光谱辐射计组成.标准准直辐射源由工作温度为50℃~1050℃的标准黑体和口径300mm的离轴抛物面作主镜的准直光管组成.光束偏转装置由口径465mm的反射镜和定位精度5″的转台组成.红外光谱辐射计采用圆形渐变滤光片CVF对入射的辐射分光,3个光谱工作区间为1μm~3μm,3μm~5μm和8μm~14μm。3个区间的测试数据显示了最小可校准的光谱辐照度低于10^-11/cm^2,系统的相对标准不确定度为2%. 相似文献
19.
本文通过测定甲酸铀酰[UO_2(HCOO)_2·H_2O]在290K-10K的红外光谱,确定了该化合物铀酰基团(O-U-O)v_(as)振动峰位,研究了温度对峰宽、峰位的影响,并采用差减及峰内标法估算了甲酸铀酰在290K-10K的同位素位移值。测得290K,77K及10K时~(238)U的v_(as)值分别为931.90cm~(-1),930.82cm~(-1)和930.74cm~(-1),~(235)U-~(238)U同位素位移△v分别为0.63cm~(-1),0.67±0.18cm~(-1)和0.71±0.21cm~(-1),位移值与理论计算值接近。 相似文献
20.
Kazufumi Ogawa 《Polymer International》1992,28(1):25-33
Studies have been carried out on KrF excimer laser light (EX), X-ray or electron beam (EB) induced polymerization of 10,12-pentacosadiynoic acid (PDA) Langmuir-Blodgett (LB) films in relation to molecular density or molecular arrangement of the films using X-ray diffraction analysis, infrared (IR) spectroscopy and Raman spectroscopy. The molecular arrangement or density of the PDA LB films was controlled by subphase conditions when the films were built up, such as pH, temperature of a subphase or salt concentration in the subphase. Polymerization sensitivity of the PDA LB film was affected by the arrangement or molecular density. On low density (A type) films the polymerization occurred by irradiation with EX, X-ray or EB, but on high density (B type) films the polymerization occurred only when the irradiation was carried out by high energy beams such as X-ray or EB. Decomposition of polymerized films was observed further by excessive irradiation of EX or X-ray, but not on the B type films. It was revealed by X-ray diffraction analysis that in the A type film, the PDA molecules bent to a larger extent than those in the B type film and the polymerization proceeded topochemically, that is, the thickness decreased little after EB irradiation in a helium atmosphere. On the other hand, in the B type film, the thickness decreased by about 10% as a result of EB irradiation. By IR reflection-absorption (RA) and Raman measurements, it was confirmed that conjugated diacetylenic bonds disappeared and conjugated double and new conjugated triple bonds appeared after high energy beam irradiations. These results support the supposition that 1,4-polymerization, i.e. polydiacetylene type polymerization, occurs easily in the A type film and 1,2- or 3,4-polymerization, i.e. polyacetylene type polymerization, occurs in the B type film, and that the polymerized A type film was decomposed at the polydiacetylenic bond when the irradiation continued further. It was also shown that the polyacetylene type polymer was obtained only when the B type film was irradiated with the high energy beam. 相似文献