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81.
82.
A method for optimal design of a multilayer diffractive optical element (MLDOE) for dual-wide-waveband optical systems is presented with consideration of polychromatic integral diffraction efficiency (PIDE) and the weight factors of PIDE for each waveband. The design process and simulation of a MLDOE in mid-wave and long-wave IR are described, and the comparison of diffraction efficiency of the MLDOEs for different design wavelength pairs determined by different methods is given. This method can make the design process more rational and more reasonable and can give a better design result than that with the conventional design method. 相似文献
83.
Si-Qi Lu Xu-Wen Li Song-Wei Li Zan Cui Yue-Wei Guo Guan-Ying Han 《Tetrahedron letters》2019,60(51):151308
Two new uncommon norhumulene-type norsesquiterpenoids, namely sinuhirtins A (1) and B (2), along with two known norcaryophyllene-type norsesquiterpenoids (3 and 4), were isolated from the South China Sea soft coral Sinularia hirta. The structures and absolute configurations of the new compounds were determined by extensive spectroscopic data analyses, and computer-assisted methods including GIAO 13C NMR and TDDFT-ECD calculations. A plausible biogenetic relationship of 1–4 was proposed. 相似文献
84.
Qingfeng Zhang Yilong Lu 《International Journal of Infrared and Millimeter Waves》2008,29(11):1019-1027
This paper presents a method of designing substrate integrated waveguide-fed (SIW-fed) slot array antennas. The design theory
is based on the circuit model of slot and via as well as the reflection canceling. To prove the feasibility of this method,
a 10-element K-band SIW-fed 45-degree linearly polarized slot array antenna with uniform power distribution is designed. By
full-wave simulation, the antenna has a good impedance bandwidth of 7.5% and uniform power distribution. Besides, a maximum
gain of 15.3dBi is obtained in the broadside and the cross polarization is suppressed below -23.5dB in the boresight. This
type of SIW-fed slot array antennas can be a good candidate for microwave and millimeter-wave applications, especially for
auto-motive collision-avoidance radar systems. 相似文献
85.
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87.
Yan Q Gao L Sharma V Chiang YM Wong CC 《Langmuir : the ACS journal of surfaces and colloids》2008,24(20):11518-11522
By direct video monitoring of dynamic colloidal self-assembly during solvent evaporation in a sessile drop, we investigated the effect of surface charge on the ordering of colloidal spheres. The in situ observations revealed that the interaction between charged colloidal spheres and substrates affects the mobility of colloidal spheres during convective self-assembly, playing an important role in the colloidal crystal growth process. Both ordered and disordered growth was observed depending on different chemical conditions mediated by surface charge and surfactant additions to the sessile drop system. These different self-assembly behaviors were explained by the Coulombic and hydrophobic interactions between surface-charged colloidal spheres and substrates. 相似文献
88.
Photocatalysis effect of nanometer TiO2 and TiO2-coated ceramic plate on Hepatitis B virus 总被引:2,自引:0,他引:2
Zan L Fa W Peng T Gong ZK 《Journal of photochemistry and photobiology. B, Biology》2007,86(2):165-169
The photocatalysis effect of nanometer TiO2 particles and TiO2-coated ceramic plate on Hepatitis B virus surface antigen (HBsAg) was investigated. The ELISA (enzyme-linked immunosorbent assay) standard method was used to assess the efficiency of TiO2 material to destroy the HBsAg. The research has shown that the suspension of TiO2 (0.5g/L) can destroy most of the HBsAg under the irradiation of mercury lamp, with the light intensity of 0.6mW/cm(2) at 365nm wavelength, or under the sunlight irradiation for a few hours. TiO2-coated ceramic plates can also destroy the HBsAg under the irradiation of mercury lamp, with the light intensity of 0.05mW/cm(2) at 365nm wavelength or under the room daylight for a few hours. 相似文献
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90.
葡萄石可以以板状、片状、葡萄状、肾状、放射状或块状集合体的形式产出,因其美丽的外观和特殊的晶体结构,近年来受到了学者的广泛关注。本文通过电子探针、粉晶X射线衍射仪、傅里叶变换红外光谱仪、显微拉曼光谱仪、紫外可见分光光度计等仪器对黄绿色葡萄石的成分、结构及谱学特征进行了分析与探讨。葡萄石的主要致色元素为Fe,且Fe3+经常取代Al3+占据八面体配位,Fe2+经常取代Ca2+存在于空隙中。电子探针数据表明:Fe与Al的含量变化整体呈现负相关关系,Fe与Ca的含量变化也整体呈现负相关关系,Fe含量相对较高的样品其黄绿色调加深。XRD图谱和拉曼光谱的结果表明:在葡萄石中绿帘石以包裹体的形式存在。红外光谱和拉曼光谱表明葡萄石中存在硅氧四面体和铝氧八面体两种架构,紫外可见吸收光谱揭示了葡萄石的致色机理。本文对葡萄石的矿物学特征及谱学特征进行系统分析,为后续葡萄石的进一步研究提供思路与实验数据。 相似文献