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1.
A new 2D coordination polymer, {[Cd_5(BTC)_2(L)_4(H_2O)_2]_n·2H_2O}_n(1, H_3BTC = 1,3,5-benzenetricarboxylic acid, HL = 3-(2-pyridyl)pyrazole) was synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, powder XRD, IR, TGA, fluorescence spectrum and elemental analysis techniques. Complex 1 belongs to the monoclinic system, P2_(1/c) space group, with a = 8.8732(4), b = 17.5179(7), c = 17.8123(7) ?, β = 103.1830(10)°, V = 2695.77(19) ?~3 and Z = 2. It features a 2D network constructed by BTC and L ligand. In addition, we analyzed Natural Bond Orbital(NBO) by using the PBE0/LANL2DZ method built in Gaussian 09 Program. The calculation results indicated obvious covalent interactions between the coordinated atoms and Cd(Ⅱ) ion.  相似文献   
2.
Two new coordination complexes[Mn(L)2(DNSA)](1) and[Co(L)(1,4-bdc)]_n (2) have been achieved under hydrothermal conditions (H2DNSA=3,5-dinitro-salicylic acid,1,4-bdc=1,4-benzenedicarboxylic acid and L=2-(2-fluoro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline).1 crystallizes in monoclinic,space group P2_1/c with a=15.871(3),b=17.274(4),c=16.078(3)A,β=113.03(3)o,V=4056.6(16)A3,Z=4,C45H22Cl2F2Mn N10O7,Mr=978.57,Dc=1.602 g/cm3,F(000)=1980,μ(Mo Ka)=0.536 mm–1,R=0.0437 and w R=0.1065.2 belongs to the monoclinic system,space group C2/c with a=14.665(2),b=30.856(4),c=11.237(2)A,β=111.166(2)o,V=4742.0(12)A3,Z=8,C27H14Cl Co FN4O4,M_r=517.80,Dc=1.602 g/cm3,F(000)=2312,μ(Mo Ka)=0.889 mm–1,R=0.0364 and w R=0.0862.The central Mn(II) ion in 1 is six-coordinated by four nitrogen atoms from two L ligands and two oxygen atoms from one DNSA anion.In 2,the two kinds of 1,4-bdc ligands link neighboring Co(II) atoms to yield a two-dimensional layer structure.The luminescence of 1 has been studied in detail.Moreover,thermal behaviors of 1 and 2 are also investigated.  相似文献   
3.
王秀艳  马帅  赵丽娜  陈妍 《无机化学学报》2011,27(11):2283-2286
水热法合成了1个一维配位聚合物[Fe2L2(btc)(H2O)2]n(L为邻菲咯啉衍生物 (2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline,btc为苯四甲酸根),并对该化合物进行了元素分析、红外,热重和单晶X-射线表征。该化合物属于三斜晶系,空间群P1,晶胞参数a=0.756 11(5) nm,b=1.003 63(4) nm,c=1.482 79(9) nm,α=91.190(1)°,β=100.569(2)°,γ=106.966(1)°,V=1.054 68(10) nm3,Z=2,R=0.035 0,wR=0.094 5。在该化合物中,苯四甲酸连接着Fe(Ⅱ)原子形成一维链状结构,链与链之间又进一步地通过π-π相互作用形成二维层状超分子结构,氢键进一步地稳定了此层状结构。  相似文献   
4.
5.
ICP-AES法测定锰铁中硅和磷方法研究   总被引:6,自引:0,他引:6  
对ICP AES法测定锰铁中硅和磷的方法进行了研究。对微波消解试样及分析方法的各种参数进行了优化 ,包括溶样酸的选择 ,溶样温度和压力的控制 ,分析谱线的选择 ,试样基体、分析酸度和干扰元素对测定结果的影响。通过各种分析参数的优化选择实现了锰铁中硅和磷的同时测定 ,取得了满意的效果。线性相关系数 :Si=0 9998,P =0 9996 ,检测限为 :Si 0 0 0 6 0 % ,P 0 0 30 % ,硅的加标回收率在 97 0 %~10 1%。分析方法准确快速 ,试剂用量少 ,线性范围宽 ,适用于低碳、中碳及高碳锰铁中硅、磷的测定。  相似文献   
6.
目前高校通信类专业所用实验设备主要完成调制、交织、信道编码和系统信令实验,较难配合3GPP标准来完成教学和科研及课程设计及毕业设计的任务。在充分研究3GPP标准文档后,在自主开发的ARM和DSP单板上完成了3G系统及4G系统的信道编解码。文中对单板结构进行了研究,对物理层协议的信道编解码功能及算法的具体实现进行了研究,包括CRC校验,卷积编码,viterbi解码,速率匹配,交织,信道复用以及传输信道到物理信道的映射等。较好地配合了教学和科研工作,对3GPP标准的演进过程的跟踪教学与研究也有一定作用。  相似文献   
7.
The new manganese(Ⅱ) coordination compound, [Mn(Cl)_2(L)_2](1, L = 11-fluorodipyrido[3,2-a:2?,3?-c]phenazine), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. 1 crystallizes in monoclinic system, space group C2/c with a = 8.419(2), b = 12.286(2), c = 28.451(6) ?, β = 95.889(3)°, V =2927.5(10) ?~3, Z = 4, C_(36) H_(16) MnF_2 Cl_2 N_8, M_r = 724.41, D_c = 1.644 g/cm~3, F(000) = 1460, μ(Mo Ka)= 0.691 mm~(-1), R = 0.0445 and wR = 0.0982. Adjacent compounds are stacked by one type of π-πinteraction among L ligands to generate a 1D supramolecular chain. Further, the 1D supramolecular chains are stacked by another type of π-π interaction among L ligands to give a 2D supramolecular layer. Moreover, the C-F···π interactions between the carbon atom of the L ligand and the pyrazine ring of the adjacent L ligand further stabilize the supramolecular layer of 1. In addition, natural bond orbital(NBO) analysis has been calculated by the B3LYP/LANL2DZ method, which shows obvious covalent interaction between the coordinated atoms and Mn(Ⅱ) ion.  相似文献   
8.
徐占林  刘福义  徐野  王佳  李远  王秀艳 《结构化学》2014,33(10):1516-1520
A new coordination polymer, [Cd2(bptc)(L)2(H2O)2]·5H2O(1, L = 2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and H4 bptc = 3,3',4,4'-biphenyltetracarboxylic acid), has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 18.868(4), b = 7.2111(14), c = 19.464(4), β = 95.75(3)°, C54H31Cd2Cl2F2N8O15, Mr = 1365.57, V = 2635.0(9)3, Z = 2, Dc = 1.721 g/cm3, S = 1.034, μ(MoKα) = 0.995 mm–1, F(000) = 1358, R = 0.0501 and wR = 0.1076. In 1, each bptc anion bridges four Cd(II) atoms to form 2D layer structures, which are further extended by π-π stacking interactions into a 3D supramolecular architecture. The thermal behavior and luminescent properties of the compound have also been studied.  相似文献   
9.
The title coordination polymer,[Zn (L) (1,4-BDC)]n (1) (L =2-(4-fluorophenyl)-1H-imidazo [4,5-f] [1,10] phenanthroline and 1,4-H2BDC=1,4-benzenedicarboxylic acid) has been synthesized by hydrothermal method and characterized by elemental analysis,IR and single-crystal X-ray diffraction. It crystallizes in triclinic,space group P1 with a=0.970 85(16) nm,b=1.076 98(18) nm,c=1.203 6(2) nm,α=63.894(2)°,β=69.051(2)°,γ=80.427(2)°,V= 1.055 4(3) nm3,Z=2,C27H15FN4O4Zn,Mr=543.80,Dc=1.711 g·cm-3,F(000)=552,μ(Mo Kα)=1.220 mm-1,R=0.037 2 and wR=0.084 4. The 1,4-BDC ligands linked the Zn(Ⅱ) atoms to form a two-dimensional layer structure. The π-π stacking interactions between L ligands extended the adjacent layers into a three-dimensional supramolecular network. Finally,the N-H…O hydrogen bonds further stabilizes the structure of 1.  相似文献   
10.
王秀艳  赵文忠 《力学学报》2001,9(3):312-316
计算固结系数的方法很多, 它们各有千秋, 但无论哪种都不能计算土体在任意固结时刻的固结系数。本文把几种计算方法的优点结合起来, 找到了-种计算任意固结时刻固结系数的新方法, 并用室内系列固结实验数据进行了计算。现场观测资料分析计算结果与之对比结果表明, 该方法行之有效。  相似文献   
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