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11.
催化褪色光度法测定痕量钍(Ⅳ)的研究 总被引:1,自引:1,他引:0
在硝酸介质中,钍(Ⅳ)能较灵敏地催化过氧化氢氧化苦胺酸偶氮变色酸褪色的指示反应,研究了该催化褪色反应的最佳条件及动力学参数,建立了一种新的动力学测定钍(Ⅳ)的方法.线性范围(0-2.5)μgTh4+/25 mL,检测限为1.673×10-9g/mL.用于稀土矿中钍(Ⅳ)的测定,结果满意. 相似文献
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测定了不同浓度、不同温度条件下含Schiff碱基的单链两亲性化合物在C16SBC6N+OH水溶液的电子吸收光谱。结果表明,两亲性分子在高温低浓度水溶液中处于较为分散状态,而在低温高浓度水溶液中呈聚集状态(双分子膜)。同时,通过量化计算比较,得出了不同聚集态时Schiff碱基的构象(即N-苯环与C-苯环的扭转二面角)。 相似文献
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The crystal structure of the title complex with the stoichiometric formula [Cu(PTA)(Phen)2](p-MBA)(H6O) (Phen=1,10-phenanthroline, PTA=terephthalic acid, p-MBA=p-toluic acid) has been determined by single-crystal X-ray diffraction. The crystal (C48H40CuN4O10, Mr=896.38) belongs to the monoclinic space group C2/c, with the following crystallographic parameters: a=1.778 6(3) nm, b=1.912 5(3) nm, c=1.389 9(2) nm, β=114.686(2)°, V=4.295 7(12) nm3, Dc=1.386 g·cm-3, Z=4, μ(Mo Kα)=0.574 mm-1, F(000)=1 860, final GooF=1.019, R=0.054 0, wR=0.148 3 for 2 644 observed reflections (I>2σ(I)). The crystal structure shows that the copper(Ⅱ) ion is coordinated with two oxygen atoms from one terephthalic acid molecule and four nitrogen atoms from two 1,10-phenanthroline molecules, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex is also reported. CCDC: 298809. 相似文献
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在甲醇和水的混合溶剂中用呋喃甲酸、4,4'-联吡啶和碳酸钴合成了一种新型配位聚合物[Co(α-Furoic acid)2(4,4'-bipy)2 (H2O)2]. 该配合物晶体属三斜晶系,空间群P 1,晶胞参数a=1.138 4(4),b=1.138 4(4),c=1.302 9(9) nm;γ=120.0°,V=1.462 3(12) nm3,Dc=1.612 g/cm3,Z=3,F(000)=729. 最终偏离因子R1=0.049 0,wR2=0.143 6. 晶体中钴原子与2个bipy的2个N原子及2个呋喃甲酸根的2个氧原子配位及2个水分子的2个氧原子配位,形成六配位的变形八面体结构,结合晶体结构进行了电化学性质研究. 结果表明,电极反应中电子转移是准可逆的,配合物稳定性好. 相似文献
16.
A copper(Ⅱ) complex [Cu2(m-MBA)4(2,2′-bipy)2(H2O)]·H2O with m-methylbenzoic acid (m-MBA), 2,2′-bipyridine (2,2′-bipy) and water molecule has been synthesized by means of hydrothermal way and characterized. Crystal data for this complex: monoclinic, space group C2/c, a=2.591 8(5) nm, b=1.414 2(3) nm, c=1.790 8(4) nm, β=131.80(3)°, V=4.893 3(17) nm3, Dc=1.379 g·cm-3, Z=4, F(000)=2 104 , Final GooF=1.034, R1=0.065 6, wR2=0.197 6. The crystal structure shows that two neighboring copper(Ⅱ) ions are linked together by two bridging-chelating m-methylbenzoic acid groups, one bridging water molecule, forming a cage structure and the Cu(Ⅱ)-Cu(Ⅱ) bond distance is 0.366 7 nm. Each copper(Ⅱ) ion is coordinated with two nitrogen atoms of one 2,2′-bipyridine molecule and four oxygen atoms from three m-methylbenzoic acid molecules and one water molecule, repectiveley, forming a distorted octahedral coordination geometry. The cyclic voltammetric behavior of the Complex was also investigated. CCDC: 648619. 相似文献
17.
The title complex of nickel (II) with 3,5-dimethylbenzoic acid, m-methylbenzoic acid and 1,10- phenanthroline was synthesized and characterized. Crystal data for this complex: triclinic, space group
P1, a=1.198 5(2) nm, b=1.315 3(2) nm, c=1.531 8(3) nm, α=92.602(3)°, β=103.292(3)°, γ=114.849(3)°, V=2.104 7(6)
nm3, Dc=1.361 g·cm-3, Z=2, F(000)=902, final GooF=1.071,
R1=0.067 2, wR2=0.155 5. The crystal structure shows that the nickel ion is coordinated with four nitrogen atoms of two 1,10-phenanthroline molecules and two oxygen atoms of one 3,5-dimethyl benzoic acid molecule, forming a distorted octahedral coordination geometry. The cyclic voltametric behavior of the complex was also investigated. CCDC: 286966. 相似文献
18.
The title complex has been synthesized by the reaction of silicotungstic acid, 1,10-phenanthroline (phen) monohydrate and cupric acetate. The crystal structure belongs to triclinic system, space group P1 with a=1.158 46(15) nm, b=1.658 8(2) nm, c=1.664 4(2) nm, α=82.090(2)°, β=76.001(2)°, γ=86.531(2)°, and V=3.072 6(7) nm3, Dc=3.887 g·cm-3, Z=2, F(000)=3 196. R1=0.086 7, wR2=0.185 8. The structure shows that the copper(Ⅱ) atom is coordinated with two nitrogen atoms from the one phen and three oxgygen atoms from three water, forming a distorted square-pyramid configuration The cyclic voltametric behavior of the complex is also reported. CCDC: 298807. 相似文献
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