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71.
为了使一些单元或线列探测器获得的扫描数据含有相应的空间信息,进而提高获得红外热像的分辨率,提出了圆锥扫描机制下基于变行频采样机理的红外图像完整重建策略。结合圆锥扫描机制下变行频采样的运动特性、优点和采样机理,通过补场搜索重建了导弹架上捕获模式下的完整红外图像。利用空间基准参量,通过计算机仿真给出了变行频采样示意图和重建图像。仿真过程表明这种技术能够有效避免因导弹自旋造成的单场边缘行采样稀疏的缺点,而获得较高分辨率的红外图像。这种技术在投入相对较低的情况下,为目标检测和跟踪研究提供可靠的数据源,具有很好的应用前景。 相似文献
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74.
针对当前森林火灾实时预警困难的问题,分
析了碲镉汞(Mercury Cadmium Telluride, MCT)单元红外探测器
用于森林防火领域的可行性。利用MCT红外探测器灵敏度
高、功耗小、成本低的特性,设计了一种基于MCT单元探测器的全方位
扫描式森林防火预警系统。该系统由太阳能和风能提供电源,并由红外
探测器实现对森林火灾中红外辐射信号的采集、放大、处理和成图;通
过RS485总线和GPRS方式实时向上位机监测中心发送数据信息。当出现火情
时,该系统能够及时向森林消防人员发送预警信息,因此可起到及时将火灾消灭在
萌芽阶段的作用。本文系统可在不同的地理环境及气候条件下提供全天候、稳
定可靠的森林火灾预警服务。 相似文献
75.
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《Surface and interface analysis : SIA》2004,36(3):213-219
Dynamic mode imaging and investigations on amplitude versus distance measurements were carried out on surfaces of single‐crystal; SrTiO3, Al2O3 and LaAlO3. Experiments were performed to optimize the imaging parameters for surfaces having varying elastic properties. The dependence of the amplitude–distance curve on different materials and the amplitude of oscillation was investigated. For SrTiO3, a low‐drive amplitude provided the linear region necessary for imaging. A large amplitude of oscillation, however, created dips in the amplitude–distance curves, presumably due to complications in the tip dynamics such as bifurcation, period doubling, etc. In the case of Al2O3 and LaAlO3, amplitude–distance curves were characterized by oscillations for lower tip sample separations and step‐like discontinuities in the stiff region. The magnitude of the oscillations and discontinuities was found to decrease with amplitude and eventually could be eliminated. Thus, for these samples a large amplitude of the cantilever provided the linear region required for imaging. It was observed also that two different surfaces of Al2O3 (c‐cut and r‐cut) yield totally different amplitude–distance curves consistent with their standard differences. The results indicate the complex behaviour of amplitude–distance curves, which not only vary from one sample to another but from one surface to another for a given sample. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
77.
The thermal denaturation of superoxide dismutase (SOD) from bovine erythrocytes was studied at various pH values of different buffers and at various concentrations of solutions of two neutral salts by differential scanning calorimetry. The experiments performed indicate that the PIPES is a buffer non-coordinating with the SOD, and that the binding of the anions studied influences more or less the thermal denaturation of SOD, but the effect on the oxidation form of SOD is more apparent. A new conformer of SOD with lower thermostability was discovered by the experiments performed in different buffers at certain pH values higher than the isoelectric point of SOD, or at higher concentrations of neutral salt solutions. The new conformer may be converted irreversibly into the usual conformer with high thermostability during heating. Based on the thermodynamic parameters obtained in distilled water and by thermodynamic analysis using the Ooi's model, it is revealed that the large enthalpy △Hdc contributed by 相似文献
78.
In situ scanning FTIR microscopy was built up for the first time in the present work, which consists of an FTIR apparatus, an IR microscope, an X-Y mapping stage, and the specially designed electrochemical IR cell and computer software. It has been demonstrated that this new space-resolvd in situ IR technique can be used to study vibration properties of micro-area, and to perform IR imaging of electrode surface. The chemical image obtained using this technique fur CO adsorption on Pt electrode illustrated, at a space-resolution of 10~(-2) cm, the inhomogeneity and the distribution of reactivity of micro-area of electrode surface. 相似文献
79.
Solventless Formation of G‐Quartet Complexes Based on Alkali and Alkaline Earth Salts on Au(111) 下载免费PDF全文
Chi Zhang Likun Wang Lei Xie Huihui Kong Prof. Dr. Qinggang Tan Liangliang Cai Qiang Sun Prof. Dr. Wei Xu 《Chemphyschem》2015,16(10):2099-2105
Template cations have been extensively employed in the formation, stabilization and regulation of structural polymorphism of G‐quadruplex structures in vitro. However, the direct addition of salts onto solid surfaces, especially under ultra‐high‐vacuum (UHV) conditions, to explore the feasibility and universality of the formation of G‐quartet complexes in a solventless environment has not been reported. By combining UHV‐STM imaging and DFT calculations, we have shown that three different G‐quartet‐M (M: Na/K/Ca) complexes can be obtained on Au(111) using alkali and alkaline earth salts as reactants. We have also identified the driving forces (intra‐quartet hydrogen bonding and electrostatic ionic bonding) for the formation of these complexes and quantified the interactions involved. Our results demonstrate a novel route to fabricate G‐quartet‐related complexes on solid surfaces, providing an alternative feasible way to bring metal elements to surfaces for constructing metal–organic systems. 相似文献
80.
The electron microanalyzer (EPMA): a powerful device for the microanalysis of filled polymeric materials 下载免费PDF全文
S. Bellayer M. Jimenez B. Gardelle G. Delaplace J. Bouquerel S. Duquesne S. Bourbigot 《先进技术聚合物》2015,26(8):1020-1026
The electron probe microanalyzer is a device often used in the field of geology or in the glass and steel industries. However, it is barely known or used in the polymer field. Thus, in this paper, we investigate the use of electron probe microanalyzer for polymer microanalyses and compared it with a scanning electron microscope equipped with an energy dispersive spectrometer. To show the unique potential of this technique only develop in our lab for polymer application, three different samples were studied: (i) a fire protective epoxy‐based coating submitted to aging in salt water, (ii) the distribution of organometallic catalysts into a thermal isolative silicone polymer, and (iii) the fouling growth of milk protein (biopolymer) on a stainless steel surface. Compared to an energy dispersive spectrometer, with an electron probe microanalyzer it is possible to quickly create X‐ray mappings of low concentration elements at a good resolution, as well as allowing the interpretation of the mechanism of action for the three samples which was impossible using only an energy dispersive spectrometer because of its too low detection resolution. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献