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1.
HT-7中性束诊断电源系统的计算机控制系统由PLC、工控机、逻辑控制和定时单元等组成。对起弧、束流引出等实验进行了研究。在多种参数下,通过调节弧压、进气量等观察了其对弧流的影响。初步实验结果表明,在高压35kV、弧流80A的情况下,束电流可以达到3.6A,引出的中性束流功率可以稳定地达到50kW以上。  相似文献   
2.
翁华森  林平  杜少武 《结构化学》2009,28(6):752-760
Three new cadmium or zinc arenedisulfonate complexes [Zn(bpp)2(L)]n 1, { [Cd(bpp)2(1,5-NDS)(H2O)2]·4H2O }n 2 and { [Cd(bpp)2(H2O2)2]·(1,5-NDS) } n 3 (L = 4,4′-bis(2-sulfonatostyryl)biphenyl, bpp = 1,3-di(4-pyd-dyl)propane and 1,5-NDS = 1,5-Naphthalenedisulfonate) have been synthesized from aqueous solution and structurally characterized by infrared spectroscopy, elemental analysis and single-crystal X-ray diffraction. Crystal data for complex 1: space group P21/n, a = 10.559(3), b = 13.138(4), c = 17.623(5)A^°, β = 100.852(3)°, V = 2400.9(12) A^°^3 Z = 2, Dc= 1.351 g/cm^3, F(000) = 1016, μ = 0.654 mm^-1, the final R = 0.0412 and wR = 0.0994; Crystal data for complex 2: space group P^-1, a = 8.5642(19), b = 10.076(3), c = 12.114(3) A^°, α = 81.623(7), β = 77.149(8), γ = 82.787(7)°, V = 1003.6(4) A^°^3 Z = 1, Dc= 1.495 g/cm^3, F(000) = 466,μ = 0.713 mm^3, the final R = 0.0241 and wR = 0.0713; Crystal data for complex 3: space group C2/c, a = 21.6024(15), b = 9.4608(5), c = 18.4656(11)A^°, β = 107.359(3)°, V= 3602.0(4)A^°^3 Z = 4, Dc= 1.533 g/cm^3, F(000) = 1704,μ = 0.780 mm^-1, the final R = 0.0229 and wR = 0.0572. The X-ray single diffraction reveals that 1 exhibits a 3D metal-organic framework formed from 2D Zn(bpp)2^2+ networks connected by L in the third dimension; 2 and 3 possess 3D and 2D architectures constructed from 1D polymeric chains through H-bond. Complexes 1-3 display photoluminescent emissions at 452 and 335 nm, respectively.  相似文献   
3.
通过检测打火短路过程中产生较大的di/dt 和du/dt 来实现高压电源的打火短路保护。在研究了中性束加速电源控制和保护特点的基础上, 设计了诊断中性束加速电源在打火短路过程中的di/dt 和du/dt 的检测电路和相应的保护电路, 实现提前对加速器高压电源打火短路的保护。  相似文献   
4.
若干含多硫基的配合物的合成方法及结构特征   总被引:1,自引:0,他引:1  
本文综述了近年来我们合成的十二种多硫基的配合物,这些配合物含有S^2-2,S^2-4,S^2-5,S^2-6,S^2-7等多硫革配体,总结了这些配合物中的金属配位构型,比较了各种多硫基的S-S键长及有关键角,归纳了配合物外光谱,并阐述了其中几个配合物与NH2NH2的反应性能。  相似文献   
5.
1INTRODUCTION The employment of transition metal ions and ap-propriate bridging ligands has become a dominant theme in the construction of some interesting ar-rays[1,2],especially for the large square grid net-works.Recently,considerable research effort has been focused on the studies of polymeric frame-works with the ligands based on imidazole.These polymers are of great interest not only due to their intriguing topologies but also the potential applications in ion exchange,magnetic and e…  相似文献   
6.
Reactions of Zn(NO3)2·6H2O and MNO3(M = Na, K and Rb) with H2mip(H2mip = 5-methylisophthalic acid) in DMF(DMF = N,N′-dimethylformamide) resulted in the formation of novel heterometallic metal-organic frameworks(Me2NH2)[ZnM(mip)2](1: M = Na; 2: M = K; 3: M = Rb, mip = 5-methylisophthalate dianion for 1~3). These complexes belong to the monoclinic system, space group P2/c and have been fully characterized by satisfactory elemental analysis, FT-IR spectra, TGA and single-crystal X-ray diffraction. Single-crystal X-ray diffraction studies reveal that 1~3 are 3D isomorphic structures based on a trinuclear unit {ZnM2(?2-COO)2(?3-COO)2} and exhibit pcu topological net and blue fluorescence.  相似文献   
7.
 在研究了诊断中性束(DNB)对控制时序要求的基础之上,针对传统控制系统带来的低可靠性和低集成度等不足,研制了一套DNB时序控制系统:包括主要由PC机和PIC单片机组成的硬件结构,以及在上下位机上开发的软件程序。实验表明该控制系统稳定可靠,为DNB装置投入HT-7实验奠定了良好的基础。  相似文献   
8.
Solvothermal reactions of Zn(NO3)2·6H2O with isophthalic acid in the presence of potassium nitrate lead to an acentric three-dimensional(3D) hetero-metallic inorganic-organic hybrid framework [ZnK2(m-BDC)2(H2O)2]n(1, m-H2 BDC = benzene-1,3-dicarboxylic acid). The crystal was characterized by elemental analysis, IR spectroscopy, TGA and single-crystal X-ray diffraction analysis. Complex 1 is of orthogonal crystal system, acentric space group Cmc21 with a = 19.764(6), b = 19.948(6), c = 12.039(4) , V = 4746(3) 3, Z = 4, C32H20O19K4Zn2, Mr = 995.66, Dc = 1.393 g/cm3, F(000) = 2000 and μ = 1.426 mm-1. The final R = 0.0761 and wR = 0.1841. The crystal exhibits remarkable blue luminescence emissions with high quantum yield of 56.02% and displays modest powder SHG efficiency of about 0.7 times that produced by a potassium dihydrogen phosphate(KDP) powder. In addition, it also exhibits potential ferroelectric property.  相似文献   
9.
ECRH负高压脉冲电源系统控制特性研究   总被引:1,自引:1,他引:0  
负高压脉冲电源是ECRH系统最重要的组成部分之一。电源系统工作的可靠性与稳定性直接影响整个ECRH系统的运行。给出了电源系统各环节的动态数学模型,设计出带有前馈的PI调节器。利用MATLAB仿真确定了调节器参数。实验结果显示,该电源系统具有较好的控制特性。  相似文献   
10.
运用傅里叶变换红外光谱、显微激光拉曼光谱以及紫外-可见光谱仪等多种光谱学手段测定了纸张上蓝色签字笔墨水的光谱,并根据吸收峰的差异对收集到的28种不同品牌、系列的蓝色签字笔进行了分类。同时还结合热重-质谱联用研究了人为老化过程中纸张上签字笔墨水成分的变化。讨论了上述谱学方法在分析鉴别纸张上蓝色签字笔墨水种类及成分的优劣,以及在研究相对书写时间和绝对书写时间中的潜在应用。  相似文献   
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