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1.
利用电子束离子源(EBIS)或者电子束离子陷阱(EBIT)产生的慢速高电荷态重离子束轰击金属靶面,离子束与靶面作用并复合辐射特征X射线;并将高荷态离子束采用离子光学系统会聚为微细束后再与靶面作用,能够辐射出微米甚至亚微米级、纳米级的微束斑X射线.本文介绍这一新型微束斑X射线源的结构、机理及其特性等.  相似文献   
2.
亚像元动态成像技术是目前实现遥感器小型化非常有效的新方法,因而研究亚像元动态成像系统的调制传递函数MTF显得非常必要和重要.介绍了亚像元动态成像的基本原理及成像过程,指出了光程差对亚像元动态成像系统MTF的影响.对亚像元动态成像系统的MTF进行了数值分析,并指出了亚像元动态成像系统的成像质量及空间分辨率与一般成像系统相比较的优点.  相似文献   
3.
光电传感器在战场侦察车上的应用与发展   总被引:2,自引:0,他引:2       下载免费PDF全文
通过对国内外战场侦察车光电传感器资料及实物的查阅和调研,并通过总结几十年的工作和设计经验,论述了战场侦察车上光电传感器在未来数字化战争中的作用和地位。对国外传感器系统在侦察车上的应用状况进行了分析,着重对各种传感器进行分析与比较,并对多光谱技术、多传感器的图像融合技术以及桅杆的应用和要求提出看法。最后对我国光电传感器在战场侦察车上的应用与发展提出了建议。  相似文献   
4.
The thermal decomposition characteristics of1,7-diazido-2,4,6-trinitrazaheptane (DATH) and multi-component systems containing DATH were studied by using DSC, TG and DTG techniques. Three –NO2 groups in the DATH molecule break away first from the main chain when DATH is heated up to 200°C. Following this process, the azido groups and the residual molecule decompose rapidly to release a great deal of heat within a short time. In the multi-component systems, DATH undergoes a strong interaction with the binder of the double-base propellant and a weak interaction with RDX. The burning rates of the two propellants were determined by using a Crawford bomb. The results showed that the burning rate rises by about 19–66% when 23.5%DATH is substituted for RDX in a minimum smoke propellant. Meanwhile, the N2 level in the combustion gases is enhanced, which is valuable for a reduction of the signal level of the solid propellant. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
5.
用双氧水绿色氧化环己酮合成己二酸的研究   总被引:16,自引:0,他引:16  
以30%的双氧水为氧化剂, 钨酸钠与含N或O的双齿有机配体(草酸)形成的络合物为催化剂, 在无有机溶剂、无相转移剂的条件下, 研究了环己酮氧化制己二酸的反应. 研究结果表明, 用廉价的草酸为配体, 最佳反应条件为钨酸钠∶草酸∶环己酮∶30%的双氧水的物质的量比为2.0∶3.3∶100∶350, 在92 ℃下反应12 h, 可制得80.6%的己二酸; 用GC-MS跟踪了氧化过程中三种主要物质环己酮、己内酯及己二酸含量随反应时间的变化关系, 提出了其主要氧化机理为环己酮首先经Beayer-Villiger氧化反应生成己内酯, 己内酯进一步氧化成己二酸.  相似文献   
6.
微量热法研究γ-Mo2N催化剂表面氢的微分吸附热   总被引:1,自引:0,他引:1  
Differential heats of H 2 adsorption on γ-Mo2N catalysts were studied by using microcalorimetry. Samples with high and medium surface areas (90 and 17 m2•g -1 ) present a homogeneous energetic distribution of surface sites, which corresponds with the preferential orientation of their (200) planes. Molybdenum nitride with low surface area (8 m2•g -1 ) displays a heterogeneous energetic distribution of H 2 adsorption sites. The higher initial differential heat of hydrogen adsorption observed for the low surface Mo nitride was attributed to species adsorbed on surface sites associated with the (111) plane.  相似文献   
7.
The novel fluorinated distyrylarylene, 4,4'-bis(2,2-di(4-fluorophenyl)vinyl)biphenyl (DFPVBi), was synthesized and fully characterized. The structure was confirmed with IR, 1↑H NMR, 13↑C NMR, 19↑F NMR and MS analyses. Its electronic and photoluminescence properties were investigated by UV-Vis absorption, cyclic voltammetry and fluorescence spectroscopy. The energy levels of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are --5.77 and --2.75 eV, respectively. The electroluminescence proper- ties of the organic light-emitting diode fabricated by DFPVBi were also studied. The device exhibits a pure blue emission peaked at 454 nm, which indicates a maximum luminance of 5872 cd/m ^2 at 14.2 V and a maximum current efficiency of 2.82 cd/A at 10V, respectively.  相似文献   
8.
陈新兵  安忠维 《有机化学》2002,22(10):694-701
选择性地向有机物中引入氟原子越来越受到重视,近年来通过碳碳不饱和键的 氟化加成来引入氟原子发展迅速。综述了碳碳不饱和键氟化加成反应的研究进展。  相似文献   
9.
Two new macrocyclic compounds, [Cu2(L)2](ClO4)4·2CH3OH (1) and [Cu(L)](ClO4)2·2H2O (2) (L = 1,3,10,12,15,18-hexaazatetracyclodocosane) were synthesized by condensation reactions involving amines and formaldehyde in the presence of copper anion. Compound 1 crystallizes in triclinic, space group Pí with a = 10.442(2), b = 14.197(3), c = 17.388(4), α = 91.218(4), β = 90.69(3), γ = 93.756(4)o, V = 2520.4(9)3, Z = 2, F(000) = 1260, Dc = 1.589 Mg/m3, Mr = 1205.92, μ = 1.137 mm-1, λ = 0.71073, the final R = 0.0668 and wR = 0.1573 for 9703 observed reflections with I > 2σ(I). Compound 2 crystallizes in monoclinic, space group C2/c with a = 16.911(2), b = 11.4172(15), c = 27.059(4), β = 107.787(2)o, V = 4974.7(12)3, Z = 8, F(000) = 2504, Dc = 1.610 Mg/m3, Mr = 602.92, μ = 1.155 mm-1, λ = 0.71073 , the final R = 0.0419 and wR = 0.1131 for 4374 observed reflections with I > 2σ(I).  相似文献   
10.
Energy components used in solid rocket propellants are beneficial for improving the energy performance, and their thermal decomposition characteristics significantly affect the combustion properties of the propellants. As a kind of energetic material with both high energy and low sensitivity (impact and friction), 5, 5'-bistetrazole-1, 1'-diolate (TKX-50) can effectively improve the energy and safety characteristics of solid propellants. Burning catalyst is another important component of solid propellants, which can significantly improve the burning rate of the propellant and reduce the pressure exponent. Among various burning catalysts, nanoscale transition metal oxides can promote the thermal decomposition of the energetic component, thus enhancing the combustion properties of the solid propellant. However, the catalytic effects of nanoscale transition metal oxides with different morphologies on the thermal decomposition of TKX-50 have rarely been studied. Based on the excellent catalytic activity of Fe2O3 for TKX-50 thermal decomposition, nano-Fe2O3 particles with spherical and tubular microstructures were used for TKX-50 thermal decomposition. The Fe2O3 nanoparticles were successfully fabricated via the solvothermal method and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. The XRD, FT-IR, and XPS results confirmed the successful fabrication of spherical and tubular Fe2O3 samples. The SEM and TEM images showed that the spherical Fe2O3 samples are composed of agglomerated Fe2O3 nanoparticles with an average particle size of 110 nm. In addition, the average diameter and length of hollow tubular Fe2O3 nanoparticles are 120 nm and 200 nm, respectively. The catalytic activities of spherical and tubular Fe2O3 for TKX-50 decomposition were studied by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) methods. The DSC and TG-DTG curves showed that both tubular and spherical Fe2O3 could effectively promote TKX-50 thermal decomposition. The first thermal decomposition peak temperature (TFDP) of TKX-50 was reduced by 36.5 K and 26.3 K in the presence of tubular and spherical Fe2O3, respectively, at 10 K·min1. The activation energy (Ea) of TKX-50, determined by the iso-conversional method, was significantly reduced in the presence of both tubular and spherical Fe2O3. The results indicated that the microstructure of the catalyst has a significant effect on its catalytic performance for TKX-50 thermal decomposition, and that tubular Fe2O3 with hollow microstructure possesses better catalytic activity than spherical Fe2O3. The excellent catalytic activity of tubular Fe2O3 can be attributed to the hollow microstructure, which has more active sites for TKX-50 thermal decomposition.  相似文献   
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