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41.
A new inorganic-organic hybrid compound [FTMA](2)[Co(NCS)(4)] (FTMA = ferrocenylmethyltrimethylammonium cation) has been synthesized and characterized by IR, UV, elemental analysis and X-ray crystallography. Co(II) atom has a distorted tetrahedral environment with four N atoms of four NCS(-) anions. In the solid state there are C-H?π interactions between adjacent ferrocenyl cations, which generate one-dimensional (1-D) supramolecular chain, and C-H?S hydrogen bonds between [FTMA](+) cations and cobalt thiocyanate anions. The title compound shows strong purple fluorescence emission in the solid state at room temperature.  相似文献   
42.
航天器密封舱微重力对流换热的数值分析   总被引:3,自引:0,他引:3  
本文以某航天器密封舱热控设计为背景,对其密封舱空间对流换热问题进行了三维流动与传热数值模拟。考虑到空间微重力等一些特殊因素等影响,着重分析模拟了密封舱压力变化、地面自然对流和空间微重力以及风扇设计状态等变化因素对密封舱对流换热影响关系。分析表明,风扇对流强化换热效果明显,可以忽略地面自然对流影响,而且使舱内空气温度均匀。  相似文献   
43.
基于Yb3+抽运动力学,结合光线追迹的方法,建立了抽运过程中的放大自发辐射模型,得到激光介质中三维含时储能分布.将速率方程理论和角谱传播理论结合,对谐振腔内调Q脉冲的形成、传播过程进行建模计算,得到激光脉冲的时间-空间分布和光束质量因子变化规律.同时进行了激光二极管抽运重频Yb:YAG片状激光器电光调Q实验,并与模拟计算的结果进行了对比校核,印证了计算模型的正确性.这为主动调Q固体激光器的设计提供了参考. 关键词: Yb:YAG激光器 Q')" href="#">调Q 时空演化  相似文献   
44.
光谱分辨条纹相机测量高能啁啾脉冲特性   总被引:2,自引:0,他引:2       下载免费PDF全文
实验演示了光谱分辩条纹相机法测量高能啁啾脉冲特性,该方法不仅可以用于测量纳秒量级的放大啁啾脉冲,还可以实时监测压缩器的调节.通过实验证实百焦耳PW演示平台输出的百焦耳量级的纳秒啁啾脉冲具有可压缩性.  相似文献   
45.
探讨了脉冲储能型重复频率片状Yb:YAG激光放大器抽运过程中的自发辐射放大(ASE)效应和能量提取过程.在Yb3+离子抽运动力学的基础上,建立了抽运过程中的自发辐射放大模型,计算了Yb:YAG晶体中三维含时储能密度分布和全片可提取能量.讨论了不同介质尺寸、掺杂浓度及厚度、介质温度参数下,自发辐射放大对储能的影响.给出了较为优化的设计,将有助于基于Yb激光材料的大能量二极管抽运的固体激光器设计. 关键词: 脉冲储能 Yb:YAG激光放大器 自发辐射放大(ASE)  相似文献   
46.
利用冷靶反冲离子动量谱仪,对低能He2+-He碰撞反应中产生的反冲靶离子和炮弹离子进行了符合测量,根据反冲靶离子的动量,研究了转移电离过程中的电荷转移机理.实验结果表明:在20—40 keV能量范围内,靶原子上的一个电子俘获到炮弹离子的基态,另一个电子直接发射到靶的连续态的直接电离及另一个电子俘获到炮弹离子的连续态的过程(ECC)是最主要的转移电离机理,且ECC过程主要发生在大碰撞参数条件下;炮弹离子俘获两个电子处在双激发态的自电离过程的贡献很小. 关键词: 冷靶反冲离子动量谱仪 转移电离机理 离子原子碰撞  相似文献   
47.
Employing the recoil ion momentum spectroscopy we investigate the collision between He^2+ and argon atoms. By measuring the recoil longitudinal momentum the energy losses of projectile are deduced for capture reaction channels. It is found that in most cases for single- and double-electron capture, the inner electron in the target atom is removed, the recoil ion is in singly or multiply excited states (hollow ion is formed), which indicates that electron correlation plays an important role in the process. The captured electrons prefer the ground states of the projectile. It is experimentally demonstrated that the average energy losses are directly related to charge transfer and electronic configuration  相似文献   
48.
Wen LL  Dang DB  Duan CY  Li YZ  Tian ZF  Meng QJ 《Inorganic chemistry》2005,44(20):7161-7170
Five novel interesting d(10) metal coordination polymers, [Zn(PDCO)(H2O)2]n (PDCO = pyridine-2,6-dicarboxylic acid N-oxide) (1), [Zn2(PDCO)2(4,4'-bpy)2(H2O)2.3H2O]n (bpy = bipyridine) (2), [Zn(PDCO)(bix)]n (bix = 1,4-bis(imidazol-1-ylmethyl)benzene) (3), [Zn(PDCO)(bbi).0.5H2O]n (bbi = 1,1'-(1,4-butanediyl)bis(imidazole)) (4), and [Cd(PDCO)(bix)(1.5).1.5H2O]n (5), have been synthesized under hydrothermal conditions and structurally characterized. Polymer 1 possesses a one-dimensional (1D) helical chainlike structure with 4(1) helices running along the c-axis with a pitch of 10.090 Angstroms. Polymer 2 has an infinite chiral two-dimensional (2D) brick-wall-like layer structure in the ac plane built from achiral components, while both 3 and 4 exhibit an infinite 2D herringbone architecture, respectively extended in the ac and ab plane. Polymer 5 features a most remarkable and unique three-dimensional (3D) porous framework with 2-fold interpenetration related by symmetry, which contains channels in the b and c directions, both distributed in a rectangular grid fashion. Compounds 1-5, with systematic variation in dimensionality from 1D to 2D to 3D, are the first examples of d(10) metal coordination polymers into which pyridinedicarboxylic acid N-oxide has been introduced. In addition, polymers 1, 4, and 5 display strong blue fluorescent emissions in the solid state. Polymer 3 exhibits a strong SHG response, estimated to be approximately 0.9 times that of urea.  相似文献   
49.
A new compound has been synthesized under hydrothermal conditions and characterized by IR, elemental analysis, XPS and single-crystal X-ray diffraction analysis. The title compound [Mn(en)3]2en0.5[HV16O38(Cl)]·4.5H2O crystallizes in monoclinic, space group C2/c, with a = 17.016(4), b = 18.858(4), c = 18.872(4) (A), β = 93.667(4)°, V = 6043(2) (A)3, Z = 4, Dc = 2.242 g/cm3, Mr = 2040.12, F(000) = 4020, μ = 2.895 mm-1, Rint = 0.0921, R = 0.0649 and wR = 0.1325. Single-crystal X-ray structure analysis indicates that the title compound consists of a polyanion [HV8VV8IVO38(Cl)]4( cage, two [Mn(en)3]22 cations, four and a half lattice waters and a half ethylenediamine. In addition, intermolecular O-H…N,O-H…O and C-H…O and C-H…O hydrogen bonds link the molecules together to form a three-dimensional structure.  相似文献   
50.
Two new one-dimension copper(II) coordination polymers [CuL(2)(NCS)(2)](n) (1) and [CuL(2)(NO(3))(2)](n) (2) (L=(C(5)H(4)N)C(CH(3))=N-N=(CH(3))C(C(5)H(4)N)) have been synthesized and characterized by IR, elemental analysis, TG technique and X-ray crystallography. Each Cu(II) atom has a distorted octahedral N(6) (1) or N(4)O(2) (2) environment with four pyridyl N atoms from four ligands and two N atoms from two NCS(-) anions for polymer 1 or two O atoms from two NO(3)(-) anions for polymer 2, respectively. A pair of bis-monodentate bridging ligands links two Cu(II) centers to form one dimension chain structure containing bimetallic 22-membered macrometallacyclic rings. 1D chain is held together with its neighboring ones via C-H?S hydrogen bonds for 1 and C-H?O hydrogen bonds, C-H?π interactions for 2 to form a 3D supramolecular structure, respectively. The luminescent properties of the polymers 1 and 2 were investigated in the solid state at room temperature.  相似文献   
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