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独居石LA-ICP-MS U-Pb法测定北大别木子店片麻杂岩变质年龄
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作者 邱啸飞 卢山松 +6 位作者 谭娟娟 童喜润 吴年文 杨小莉 邵鑫 刘飞 杨小丽 《岩矿测试》 CAS 北大核心 2025年第1期75-87,共13页
北大别构造带木子店片麻杂岩是目前华南陆块范围内出露的最古老岩石,但有关其变质时代和构造性质等问题仍缺乏研究。对这些岩石的变质时代开展研究,对于了解华南陆块早期地壳演化过程具有重要意义。本文利用LA-ICP-MS方法对木子店片麻... 北大别构造带木子店片麻杂岩是目前华南陆块范围内出露的最古老岩石,但有关其变质时代和构造性质等问题仍缺乏研究。对这些岩石的变质时代开展研究,对于了解华南陆块早期地壳演化过程具有重要意义。本文利用LA-ICP-MS方法对木子店片麻杂岩中两件片麻岩样品进行了独居石的微区原位U-Pb定年和微量元素分析,采用独居石标准物质44069对年龄进行校正,独居石标准物质Trebilcock作为监控,测试结果与其推荐值在误差范围内相一致。结果显示,大多数独居石具有均一、无环带特点,且存在重稀土元素明显亏损以及负Eu异常,暗示其可能形成于变质成因。两件片麻岩样品的独居石U-Pb年龄分别为129±1Ma和130±1Ma,代表了木子店片麻杂岩发生变质作用的时间,这一年龄与木子店地区早白垩世花岗岩的侵位年龄基本一致,也与北大别造山带内大量出露的混合岩时代相吻合。研究认为大别造山带早白垩世加厚地壳的伸展垮塌和造山山根拆沉,引起了变质作用和同时代的岩浆活动,将北大别构造带从挤压向伸展的构造转换时间限定在~130Ma。 展开更多
关键词 木子店片麻杂岩 变质作用 独居石 北大别构造带 英云闪长片麻岩 la-ICP-MS
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3-羟基丙酸甲酯加氢合成1,3-丙二醇反应中La对Cu/SiO_(2)催化剂的修饰作用 被引量:1
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作者 林丽娜 康金灿 +4 位作者 张传明 李伟杰 李昌鑫 赖恩义 朱红平 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期63-72,共10页
[目的] 3-羟基丙酸酯加氢制备1,3-丙二醇(1,3-PDO)过程中存在β-羟基脱除等副反应,导致1,3-PDO的选择性和收率不高,其中高效催化剂的开发是解决该问题的关键.[方法]采用蒸氨法制备了不同添加量La修饰的20Cu/SiO_(2)催化剂,对其进行催化... [目的] 3-羟基丙酸酯加氢制备1,3-丙二醇(1,3-PDO)过程中存在β-羟基脱除等副反应,导致1,3-PDO的选择性和收率不高,其中高效催化剂的开发是解决该问题的关键.[方法]采用蒸氨法制备了不同添加量La修饰的20Cu/SiO_(2)催化剂,对其进行催化性能评价,并通过H_(2)程序升温还原(H_(2)-TPR)、X射线衍射(XRD)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)和N_(2)物理吸附-脱附对其进行表征.[结果] 20Cu-0.50La/SiO_(2)的催化性能最佳,它显著地提高了3-羟基丙酸甲酯(3-HMP)加氢制1,3-PDO的催化活性和稳定性,其中3-HMP转化率为91.8%,1,3-PDO的选择性和收率分别为85.2%和78.2%.这是在高液时空速(LHSV=0.10 h^(-1))的条件下取得的最佳结果.[结论] La的加入与Cu产生了强相互作用,增强了催化剂中Cu的分散性,同时提高了Cu^(+)物种表面浓度,使活性Cu的比表面积增加,从而提高了加氢反应的活性和稳定性. 展开更多
关键词 3-羟基丙酸甲酯 加氢 1 3-丙二醇 蒸氨法 CU催化剂 la助剂
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高压辅助溶胶-凝胶法制备La掺杂TiO_(2)光催化剂及其可见光降解甲基橙研究
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作者 王雪怡 王智远 +5 位作者 余伟 周冰鑫 徐榕 杨兴东 何辉超 贾碧 《材料导报》 EI CSCD 北大核心 2024年第2期51-55,共5页
根据溶胶-凝胶法和水热法制备TiO_(2)的优点和不足,本工作提出了一种高压辅助溶胶-凝胶法(简称HG法)可控地制备La掺杂TiO_(2)。通过该方法,可以高效制备锐钛矿相La掺杂TiO_(2),且制得样品纯度高,分散性好。通过控制La掺杂比例(0.05%、0.... 根据溶胶-凝胶法和水热法制备TiO_(2)的优点和不足,本工作提出了一种高压辅助溶胶-凝胶法(简称HG法)可控地制备La掺杂TiO_(2)。通过该方法,可以高效制备锐钛矿相La掺杂TiO_(2),且制得样品纯度高,分散性好。通过控制La掺杂比例(0.05%、0.10%、0.15%、0.20%、0.25%,质量分数,下同),可以调控TiO_(2)禁带宽度变化(3.15~2.80 eV);其中,0.20%La掺杂TiO_(2)(0.20%La-TiO_(2))的禁带宽度可达2.80 eV。甲基橙(MO)光催化降解实验结果表明,0.20%La-TiO_(2)的光催化活性优异,其在可见光照射下160 min内对MO的降解率可达92%,是本征TiO_(2)的38.30倍;·O_(2)-是驱动0.20%La-TiO_(2)光催化降解MO的主要活性物质。本工作提出的高压辅助溶胶-凝胶法可为制备高活性TiO_(2)基光催化剂提供有益的方法及条件参考。 展开更多
关键词 光催化活性 la掺杂TiO_(2) 锐钛矿相 高压辅助溶胶-凝胶法
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La/Al天然沸石对水中F^(-)的吸附及再生
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作者 钱程 张峰榛 +1 位作者 曾奇 龚长林 《化工新型材料》 CAS CSCD 北大核心 2024年第1期214-219,共6页
以天然沸石为原料,制备La/Al负载天然沸石,用于水中F^(-)的吸附,并对其吸附动力学、等温吸附性能、再生能力和吸附机理进行探讨。结果表明,该吸附剂对F^(-)的吸附符合拟二级动力学模型和Langmuir模型,在298K温度条件下,理论最大吸附量为... 以天然沸石为原料,制备La/Al负载天然沸石,用于水中F^(-)的吸附,并对其吸附动力学、等温吸附性能、再生能力和吸附机理进行探讨。结果表明,该吸附剂对F^(-)的吸附符合拟二级动力学模型和Langmuir模型,在298K温度条件下,理论最大吸附量为19.2mg/g。pH的升高不利于F^(-)的吸附。Cl^(-)、NO_(3)^(-)对F^(-)的吸附影响较小,而HCO_(3)^(-)和H_(2)PO_(4)^(-)的存在不利于F^(-)的吸附。在0.5mol/L NaOH条件下,经过5次循环再生,吸附剂对F^(-)的吸附量降低16.7%。SEM、BET、EDS-mapping和XPS分析表明,F^(-)的吸附机理主要为配体交换。 展开更多
关键词 la/Al 天然沸石 F^(-)吸附 再生
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One-dimensional Supramolecular Chain Based on a Dinuclear Terbium(Ⅲ) 4-Cyanobenzoate Complex 被引量:1
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作者 李国清 李艳 +4 位作者 邹文强 陈其湧 吴阿清 郑发鲲 郭国聪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第7期805-810,共6页
A new dinuclear Tb(Ⅲ) 4-cyanobenzoate complex [Tb2(4-cba)6(phen)2] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solut... A new dinuclear Tb(Ⅲ) 4-cyanobenzoate complex [Tb2(4-cba)6(phen)2] (4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline) 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data: C72H40N10O12Tb2, Mr=1554.98, triclinic Pi, a = 9.903(3), b = 11.769(8), c = 15.078(8)A, a = 111.42(12), It = 96.37(19), γ = 101-24(14)°, V= 1572(1)A3, Z= 1, Dc = 1.642 g/cm^3, F(000) = 768 μ = 2.305 mm^-1, the final R = 0.0205 and wR = 0.0543 for 5479 reflections with I 〉 2σ(I). Structural analysis shows that 1 displays an isolated dinuclear structure. Two eight-coordinated Tb(Ⅲ) ions are bridged by four 4-cba ligands in the syn-syn bidentate coordination mode, and two other 4-cba ligands chelate these two Tb(Ⅲ) ions. The title complex molecules are connected through π-π stacking interactions to generate a one-dimensional supramolecular chain, The characteristic infrared spectra, luminescent properties and thermogravimetric analyses have also been discussed. 展开更多
关键词 terbium(Ⅲ) complex 4-cyanobenzoic add crystal structure π-π stacking optical spectroscopy
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Hydrothermal Syntheses and Crystal Structures of Three Lanthanide(Ⅲ)Complexes Based on Carboxyl Derivatives of 1,10-Phenanthroline 被引量:5
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作者 乔宇 尉兵 +5 位作者 李秀颖 车广波 刘春波 张兴晶 朱恩伟 刘凤 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期73-81,共9页
Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid... Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Structural analyses revealed that complexes 1~3 possess similar porous three-dimensional frameworks with the point symbol {4^(12)·6~3}. Meanwhile, complexes 1~3 exhibit excellent thermal stabilities and complex 2 exhibits characteristic luminescent property. 展开更多
关键词 lanthanide(Ⅲ) complex 2-(4-carboxyphenyl)imidazo(4 5-f)(1 10)phenanthroline benzene-1 4-dicarboxylic acid crystal structure luminescence
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The First Example of a Supramolecular Structure Containing [2-(1H-Pyrazol-3-yl)-pyridine] Complex and both α-and β-Octamolybdates 被引量:1
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作者 赵文秀 董顺福 +2 位作者 张伟萍 彭军 庞海军 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第8期1013-1017,共5页
The title compound, [Ni(C8N3H7)3]4[Mo8O26]2·6H2O 1, has been synthesized from the reaction of 2-(1H-pyrazol-3-yl)-pyridine (L) with (NH4)2MoO4·2H2O and NiCl2·6H2O. Elemental analysis, IR, UV spe... The title compound, [Ni(C8N3H7)3]4[Mo8O26]2·6H2O 1, has been synthesized from the reaction of 2-(1H-pyrazol-3-yl)-pyridine (L) with (NH4)2MoO4·2H2O and NiCl2·6H2O. Elemental analysis, IR, UV spectra and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure of the compound. Crystal data: C96H96Mo16N36Ni4O58, Mr = 4451.97, monoclinic system, space group P21/n, a = 20.846(5), b = 14.825(5), c = 23.122(5) A ,β= 91.594(5)°, V = 7143(3)A^3, Z = 2, F(000) = 4344, Dc = 2.070 g/cm^3,μ = 1.968 mm^-1, R = 0.0452 and wR = 0.1056 for 17102 independent reflections (Rint = 0.0442) and 11074 observed reflections (I 〉 2σ(I)). Structural analysis indicates that two kinds of octamolybdates ([α-Mo8026]^4- and [β-Mo8026]^4-) co-exist in the compound. This is the first example of a supramolecular structure containing L complex as well as both α- and β-octamolybdate clusters. 展开更多
关键词 crystal structure OCTAMOLYBDATE 2-(1H-pyrazol-3-yl)-pyridine supramolecularnetwork nickel(II complex
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Structure of Complexes of Lanthanides with N,N′-Dimethyl-3-Oxa-Glutaramic Acid
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作者 黄念 王建晨 +3 位作者 张平 孙大陟 张静 刘涛 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第1期12-16,共5页
A new stripping agent N,N-dimethyl-3-oxa-glutaramic Acid (DOGA) was used in TRPO process to simplify the TRPO process. The structures of the complexes of the DOGA with Eu(Ⅲ), Nd(Ⅲ), La(Ⅲ) were characterized with ex... A new stripping agent N,N-dimethyl-3-oxa-glutaramic Acid (DOGA) was used in TRPO process to simplify the TRPO process. The structures of the complexes of the DOGA with Eu(Ⅲ), Nd(Ⅲ), La(Ⅲ) were characterized with extended X-ray absorption fine structure spectroscopy (EXAFS), infrared spectra (IR) and mass spectra (MS). The molecular formula of the complexes of Eu(Ⅲ) and Nd(Ⅲ) is deduced to be M(DOGA)_3, and only La(Ⅲ) can form the complex HM(DOGA)_4 under condition of high consistency of the DOGA. The coordination number of Ln(Ⅲ) in the complexes is 8, and all of coordinated donor atoms are O atoms. For Eu(Ⅲ), Nd(Ⅲ), the coordination numbers of O atom in the first coordination shell is 6 and the average coordination bond lengths of Ln-O are 0 240 nm, 0 244 nm respectively, while the numbers of the second O shell are 2.4, and the average coordination bond lengths of Ln-O are 0 260 nm, 0 262 nm. For La(Ⅲ), the coordination numbers of O atom in the first coordination shell is 6 and the average coordination bond lengths of La-O are 0 258 nm, while the number of O atom in the second coordination shell is 4.4, and the average coordination bond length of La-O is 0 28 nm. The results of IR and MS show that there is no water coordinating with Ln(Ⅲ) in the complexes. 展开更多
关键词 Eu(Ⅲ) Nd(Ⅲ) la(Ⅲ) EXAFS structure of the complexes rare earths
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Study on Interaction of La-Enoxacin Complex and Bovine Serum Albumins by Fluorescence
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作者 李桂芝 刘永明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期235-238,共4页
A new complex La(ENX)_3Cl_3·2H_2O was synthesized. The interaction between La-Enoxacin complex and bovine serum albumins (BSA) were studied by fluorescence and UV-Vis absorption spectra. The research results indi... A new complex La(ENX)_3Cl_3·2H_2O was synthesized. The interaction between La-Enoxacin complex and bovine serum albumins (BSA) were studied by fluorescence and UV-Vis absorption spectra. The research results indicate that the combination reaction of them is a single static quenching process, La-Enoxacin complex strongly bound BSA, the equilibrium constant K_0=1.45×107 L·mol -1 (at 25 ℃). The shortest binding distance(r) and energy transfer efficiencies(E) between donor (BSA) and acceptor (La-Enoxacin) obtained by Frster′s nonradiative energy transfer mechanism are as follows, r=4.07 nm, E=0.118. The hydrophobic force plays major role in the reaction. 展开更多
关键词 la 3+-complex enoxacin BSA fluorescence quenching INTERACTION rare earths
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Synthesis and Structure of a La(Ⅲ) Complex of 1,10-Phenanthroline-2,9-dicarboxylate:a Three-dimensional Network via Hydrogen Bonding Interactions
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作者 GAO Qian XIE Ya-Bo CHEN Yuan WANG Dao 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期137-142,共6页
A new La(Ⅲ) complex, {[La(L)(NO3)(H2O)3]·H2O}n (L = 1,10-phenanthroline- 2,9-dicarboxylate), has been synthesized and structurally determined by X-ray diffraction analysis. The complex crystallizes in ... A new La(Ⅲ) complex, {[La(L)(NO3)(H2O)3]·H2O}n (L = 1,10-phenanthroline- 2,9-dicarboxylate), has been synthesized and structurally determined by X-ray diffraction analysis. The complex crystallizes in the monoclinic system, space group P21/c with a = 7.7358(17), b = 8.1664(18), c = 28.271(6) A, β= 95.184(4)°, V= 1778.6(7) A3, Z = 4, C14H14LaN3O11, Mr = 539.19, Dc = 2.014 g/cm^3, μ= 2.471 mm^-1, F(000) = 1056, the final R = 0.0350 and wR = 0.0659. In this complex, each metal center adopts a ten-coordination geometry formed by two N atoms from a ligand L and eight O atoms from three H2O molecules, a nitrate ion and carboxylates of two ligands. Each ligand adopts a N2,O3-pentdentate coordination mode using two N and two O atoms chelating a La(Ⅲ), and using another O atom of carboxylate to bridge another La(Ⅲ) center resulting in a 1D helical chain molecule. Intermolecular strong O-H…O and weak C-H…O hydrogen bonds extend the 1D chain structure into a 3D supramolecular architecture. 展开更多
关键词 hydrogen bonding 1 10-phenanthroline-2 9-dicarboxylate la(Ⅲ) complex synthesis
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Synthesis,Structure and DFT Calculations of a Novel Copper(Ⅱ)Complex Based on Tert-butyl 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate 被引量:3
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作者 程泽英 胡慧萍 +3 位作者 杨金鹏 邱雪景 王彩霞 姬广富 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期795-804,共10页
A novel copper(Ⅱ) complex with tert-butyl 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate(ampy) was synthesized and structurally characterized by elemental analysis, FT-IR spectrum, electrospray ioniza... A novel copper(Ⅱ) complex with tert-butyl 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate(ampy) was synthesized and structurally characterized by elemental analysis, FT-IR spectrum, electrospray ionization-mass spectrometry, UV-vis spectrum and single-crystal X-ray diffraction, respectively. A mononuclear copper(II) complex with ampy, [Cu(ampy)Cl2](1), was formed irrespective of the metal-to-ligand molar ratios([Cu2+]:[ampy] = 0.5:1, 1:1, and 2:1) as a single product. Complex 1 crystallizes in the orthorhombic system, space group Pbca with a = 12.343(2), b = 18.928(3), c = 20.058(4) A, V = 4686.1(14) A3, Z = 8, Dc = 1.3349(4) g/cm3, F(000) = 1920, S = 1.016, R = 0.0693 and w R = 0.1721 for 3151 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that the central copper(II) ion is bound by pyridyl N, tertiary amine N and carbonyl O atoms of the quadridentate ampy as well as two Cl anions, constructing a slightly distorted octahedral geometry. Complex 1 further constructs a stable 3D supramolecular architecture by intermolecular C–H…Cl hydrogen bonds. In addition, the molecular geometry was calculated by density functional theory(DFT/B3LYP) method with the basis sets(6-31+G(d,p) for H, C, N, O and Cl atoms, and LANL2 DZ for Cu atom, respectively). The calculated results show that the optimized geometrical parameters are in good agreement with the experimental data. Natural bond orbital(NBO) analysis and frontier molecular orbitals(FMOs) analysis were investigated at the same level. 展开更多
关键词 copper(Ⅱ) complex crystal structure tert-butyl2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate (ampy) DFT calculation
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Synthesis of La/N Co-Doped SrTiO<sub>3</sub>Using Polymerized Complex Method for Visible Light Photocatalysis
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作者 Uyi Sulaeman Shu Yin Tsugio Sato 《Advances in Nanoparticles》 2013年第1期6-10,共5页
Lanthanum and nitrogen co-doped SrTiO3 was synthesized using polymerized complex method with Ti(OC3H7)4, SrCl2·6H2O and La(NO3)3·6H2O as starting materials followed by calcinations in NH3. Ethylene glycol an... Lanthanum and nitrogen co-doped SrTiO3 was synthesized using polymerized complex method with Ti(OC3H7)4, SrCl2·6H2O and La(NO3)3·6H2O as starting materials followed by calcinations in NH3. Ethylene glycol and anhydrous citric acid were used as the precursors of synthesis. The samples were characterized using XRD, TEM, DRS, BET, EDX and XPS. The cubic-perovskite type of La/N co-doped SrTiO3 nanoparticle could be successfully synthesized. The photocatalytic activity of SrTiO3 for DeNOx ability in visible light region (λ > 510 nm) could be improved by co-doping of La3+ and N3_. The high visible light photocatalytic activity of this substance was caused by a narrow band gap energy that enables to absorb visible light. 展开更多
关键词 Photocatalysis Visible Light SRTIO3 Polymerized complex la-Doping N-DOPING
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A SIMPLE ACCESS TO UNSOLVATED MONOMERIC COMPLEXES OF EARLY LANTHANIDE IODIDES(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)VIA THE REACTION OF[(CH_3OCH_2CH_2C_5H_4)_2LnCl]_2 WITH NaI AND X-RAY CRYSTAL STRUCTURE OF THE LANTHANUM COMPLEX
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作者 Chang Tao QIAN Bing Wang Xiao Fan ZHENG Dao Li DENG Jie SUN Laboratory of Organometallic Chemistry,Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第9期841-844,共4页
(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvat... (CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvated monomer with lanthanum(Ⅲ)in a trigonal bipyramidal coordination geometry if the cyclopentadienyl ring is regarded as occupying a single polyhedral vertex. 展开更多
关键词 OCH Ln=la Nd)VIA THE REACTION OF CH3OCH2CH2C5H4 LN A SIMPLE ACCESS TO UNSOLVATED MONOMERIC complexES OF EARLY laNTHANIDE IODIDES ND la VIA NAI
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Lanthanide Complex [Nd(dpdo)_4(H_2O)_3][ClO_4]_3·4.5H_2O·dpdo Containing Framework Based on 4,4′-Dipyradine-Dioxide
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作者 马宝清 孙豪岭 高松 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第4期313-317,共5页
A novel lanthanide coordination polymer formulated as [Nd(dpdo) 4(H 2O) 3] 3·4.5H 2O·dpdo 1(dpdo=4,4′-dipyrazine-dioxide) was synthesized and structurally characterized. The Nd 3+ ions are bridged b... A novel lanthanide coordination polymer formulated as [Nd(dpdo) 4(H 2O) 3] 3·4.5H 2O·dpdo 1(dpdo=4,4′-dipyrazine-dioxide) was synthesized and structurally characterized. The Nd 3+ ions are bridged by dpdo ligands in a cis-mode to form a zigzag chain along direction. Meanwhile, each Nd 3+ ion is coordinated with three terminal dpdo molecules. One of them is overlapped with the bridging one through π-π stackings, and the other two are bound to the opposite directions of the bridging ones, producing a ribbon-like motif with rectangular cavity. These adjacent ribbons are connected through inter-molecular π-π stackings to give parquet-like architecture with a large rectangular channel (1.108 nm×1.660 nm) in which the crystal lattice water molecules and ClO 4 - anions are included. Thermal analysis shows that the solvate dpdo and water molecules can be removed at lower temperature, while coordinated dpdo molecules are lost simultaneously at higher temperature. 展开更多
关键词 rare earths π-π stacking lanthanide complex crystal engineering dipyradine-dioxide SUPRAMOLECULE
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Two-dimensional Supramolecular Structure of a Mercury(Ⅱ) Iodide Complex with Organosulfide
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作者 闫春凤 岳呈阳 +4 位作者 吴明燕 陈莲 冯蕊 江飞龙 洪茂椿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期453-456,共4页
A mercury(Ⅱ) iodide complex with organosulfide [Hg(pymt)(pymtH)I] 1 (pymt = the anion of pyrimidine-2-thiolate) has been synthesized by slow evaporation of the solution at room temperature and structurally ch... A mercury(Ⅱ) iodide complex with organosulfide [Hg(pymt)(pymtH)I] 1 (pymt = the anion of pyrimidine-2-thiolate) has been synthesized by slow evaporation of the solution at room temperature and structurally characterized by single-crystal X-ray diffraction. Basic ideas and data collected are given. X-ray diffraction analysis reveals that complex 1 is mononuclear. Crystallographic data: C8H7HgIN4S2, Mr = 550.79, monoclinic system, space group P21/c, a = 11.218(4), b = 9.551(3), c = 15.877(4) A^°, β = 129.697(15)°, V = 1308.9(7) A^°^3, Z = 4, Mr = 550.79, Dc = 2.795 g/cm^3, F(000) = 995, μ(MoKa) = 14.415 mm^-1, 2(MoKa) = 0.71073 A^°, T= 293(2) K, 2θmax = 54.9°, GOOF= 1.053, the final R = 0.0310 and wR = 0.0742 for 2547 observed reflections with I 〉 2σ(I) (refinement on F^2). Complex 1 is connected through hydrogen bonds to give a one-dimensional supramolecular chain structure. Furthermore, π-π interactions are also found between the pyrimidine rings with the center-to-center distances of 3.439(4) and 3.603(4) A^°, so complex 1 expands the chains into a two-dimensional network. 展开更多
关键词 mercury(Ⅱ) complex organosulfide crystal structure π-π stacking hydrogen bonding
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Two Fluorescent Complexes Assembled by Schiff Base 2-Methoxy-6-(phenyliminiomethyl) Phenolate Ligand
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作者 单亦韩 陈小菊 +1 位作者 秦毅 赵国良 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第6期811-816,共6页
Two d10 metal complexes Zn(NCS)2(C14HI3NO2)2 (1) and [Cd(NO3)2(CI4HI3NO2)2]. 4H20 (2) assembled by 2-methoxy-6-(phenyliminiomethyl) phenolate ligand (C14H13NO2, HL) have been synthesized and characteri... Two d10 metal complexes Zn(NCS)2(C14HI3NO2)2 (1) and [Cd(NO3)2(CI4HI3NO2)2]. 4H20 (2) assembled by 2-methoxy-6-(phenyliminiomethyl) phenolate ligand (C14H13NO2, HL) have been synthesized and characterized by elemental analysis, IR and TG The single-crystal X-ray diffraction studies demonstrated that complex 1 crystallizes in monoclinic, P21/c space group with a = 17.321(7), b = 11.781(0), c = 15.593(2) A, fl = 110.273(6)°, V = 2984.95 A3, Z = 4, C30H26N404SzZn, Mr = 636.04, F(000) = 1312, Dc = 1.415 g/cm3,μ(MoKa) = 1.004 mm"1, the final R = 0.0403 and wR = 0.0900 for 21441 observed reflections with I 〉 20(/). Complex 2 is of monoclinic system, space group C2/c with a = 16.7767(2), b = 10.8989(2), c = 17.4928(2) A, fl = 90.614(9)°, V= 3198.37 A3, Z = 4, C28H34N4O14Cd, Mr= 731.25, F(000) = 1528, Dc = 1.568 g'cm^-3, μ(MoKa) = 0.757 mm-1, the final R = 0.0361 and wR = 0.0857 for 19811 observed reflections with I 〉 2σ(I). The two complexes were formed by Schiff base 2-methoxy-6-(phenyliminiomethyl) phenolate ligand and formed a 3D supramolecular architecture by π-πstacking interactions. Moreover, the complexes are luminescent in the solid state. These observations indicate that the complexes are promising system for the development of potential photoactive materials. 展开更多
关键词 d^10 metal complex 2-methoxy-6-(phenyliminiomethyl) phenolate ligand crystal structure luminescent
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Synthesis and Crystal Structure of a Ni(Ⅱ) Complex of 2'-[4-N,N'-(Dimethylaminobenzyl- idene)]-3,5-dihydroxybenzoylhydrazide and Its Spectral Properties
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作者 贾文平 杨健国 +1 位作者 李芳 潘富友 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1635-1639,共5页
A new nickel(II) complex [NiL2](DMF)4 (HL = 2'-[4-N,N'-(dimethylamino- benzylidene)]-3,5-dihydroxybenzoylhydrazide) has been synthesized and its structure was characterized by IR,UV-Vis,1H NMR and elemental ... A new nickel(II) complex [NiL2](DMF)4 (HL = 2'-[4-N,N'-(dimethylamino- benzylidene)]-3,5-dihydroxybenzoylhydrazide) has been synthesized and its structure was characterized by IR,UV-Vis,1H NMR and elemental analysis. The fluorescence emission mechanism of the complex was discussed by fluorimetric spectra. The single-crystal structure was determined by X-ray diffraction analysis. The crystal belongs to the triclinic system,space group P1 with a = 0.9918(4),b = 1.1297(4),c = 1.1331(4) nm,α = 76.860(7),β = 75.105(6),γ = 89.022(7)°,V = 1.1936(8) nm^3,Z = 1,μ = 0.472 mm^-1,Dc = 1.319 g/cm^3,F(000) = 502 and Rint = 0.0913. In the title compound,the nickel(II) atom is four-coordinated with two nitrogen atoms from amide and two oxygen atoms from keto group. The complex is centrosymmetric with nickel located at the center. 展开更多
关键词 nickel(II) complex 2'-[4-N N'-(dimethylaminobenzylidene)]-3 5-dihydroxyben- zoylhydrazide crystal structure spectral properties
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Polarographic behavior of 1,4,7-triazacycloanane-N,N',N"-tris (meth-ylphonic acid) (NOTP)-Bi(Ⅲ) complex
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作者 GAO Jinzhang, HE Hui, YANG Wu, and RANG JingwanInstitute of Chemistry, Northwest Normal University, Lanzhou 730070, China 《Rare Metals》 SCIE EI CAS CSCD 2002年第4期250-254,共5页
The polargraphic behavior of Bi(Ⅲ)-NOTP complex has been investigated inaqueous solution. It was found that under the conditions of pH 3.0 and of 0.02 mol/L NH_4Cl, theBi(Ⅲ)-NOTP system gives a sensitive second orde... The polargraphic behavior of Bi(Ⅲ)-NOTP complex has been investigated inaqueous solution. It was found that under the conditions of pH 3.0 and of 0.02 mol/L NH_4Cl, theBi(Ⅲ)-NOTP system gives a sensitive second order derivative wave at -0.340 V(vs SCE), which isproved to be an adsorptive complex wave. The composition of the complex is Bi(Ⅲ):NOTP. Furthermore,the peak current is linear to the concentration of Bi(Ⅲ) in the range from 3.0x10^(-8) to5.0x10^(-6) mol/L. Artificial and practical samples have been detected with high sensitivity andreceptivity. 展开更多
关键词 determination of bismuth Bi(Ⅲ)- NOTP complex 1 4 7-triazacycloanane-N N′ N″-tris(methylphonic acid)
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Hydrothermal Synthesis,Crystal Structure and Properties of a Lanthanum(Ⅲ) Complex Based on a N,O-Donor Ligand
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作者 刘春波 刘欣竹 +3 位作者 李微微 张文通 赵程程 车广波 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第7期1001-1006,共6页
A novel metal-organic complex [La(o-NCP)3]n (o-HNCP = 2-(2-carboxyphen- yl)imidazo(4,5- f)(1,10)-phenanthroline) has been hydrothermally synthesized and characterized by elemental analysis, infrared analysis... A novel metal-organic complex [La(o-NCP)3]n (o-HNCP = 2-(2-carboxyphen- yl)imidazo(4,5- f)(1,10)-phenanthroline) has been hydrothermally synthesized and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The complex crystallizes in triclinic, space group P1 with a = 9.898(2), b = 16.193(3), c = 16.909(3) A, a = 67.68(3), β = 80.85(3), y = 78.78(3)°, V= 2448.2(8) A3, Z = 2, Mr = 1156.9, Dc = 1.569 g/cm3,μ = 0.71073 A, F(000) = 1164, GOOF = 1.065, the final R = 0.051 and wR = 0.123 for 8539 observed reflections with I 〉 2o(I). The complex exhibits a one-dimensional double chain structure. The adjacent chains are further connected by N-H...N hydrogen bonds which help to form a two-dimensional suprarnolecular architecture. Furthermore, the complex exhibits excellent thermal stability and luminescent property. 展开更多
关键词 lanthanum(III) complex 2-(2-carboxyphenyl)imidazo(4 5-f)-(1 10)-phenanthroline crystal structure PHOTOLUMINESCENT
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Synthesis, Characterization and Luminescence of Lanthanide Chloride Complexes with N,N,N',N'-Tetra[(2-benzimidazolyl) methyl]-1,2-Ethanediamine
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作者 Ming Jie ZHANG Ling HUANG +6 位作者 Xiu Fang SHI De Qing GAO Song Lin LI Gui Mei CAI Yan Yi HUANG Guang Qing YAO Jing LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第7期651-654,共4页
N,N,N',N'-tetra[(2-benzimidazolyl)methyl]-1,2-ethanediamine (EDTB) lanthanide chloride complexes were prepared (Ln3+=Eu3+, Tb3+ or Gd3+). The results of single crystal X-ray structural analysis show that [(ED... N,N,N',N'-tetra[(2-benzimidazolyl)methyl]-1,2-ethanediamine (EDTB) lanthanide chloride complexes were prepared (Ln3+=Eu3+, Tb3+ or Gd3+). The results of single crystal X-ray structural analysis show that [(EDTB)GdCl2]Cl(C2H5OH)(H2O)2 crystal is in space group P21 / c with a=8.848(2) ?, b=26.313(5) ?, c=18.929(4) ?, β=97.82(3)o, V=4366(2) ?3, Z=4. The luminescent properties of the terbium and europium complexes have been studied. 展开更多
关键词 N N N( N(-Tetra[(2-benzimidazolyl)methyl]-1 2-ethanediamine lanthanide complexes crystal structure luminescent properties.
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