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101.
在水热条件下,以3,5-二((4''-羧基苄基)氧)苯甲酸(H3bcb)和4''-(4-吡啶基)-2,2'':6'',2"-三联吡啶(PYTPY)为混合配体构筑了2个过渡金属配合物[Co(H2bcb)2(PYTPY)]n (1)和[Mn(H2bcb)2(PYTPY)]n (2),利用元素分析、红外光谱以及单晶X射线衍射表征其结构。分析表明配合物1和2为一维链状结构。此外,2个配合物展示了优良的热稳定性。磁化率的测试结果表明,配合物1和2在2 K和8 K以下时展示了反铁磁相互作用。 相似文献
102.
《Journal of Coordination Chemistry》2012,65(1):155-168
A polymeric silver(I) complex, [Ag4(μ-pydc)2(μ-pm)2]n (1) (pydc = pyridine-3,5-dicarboxylate and pm = pyrimidine), has been synthesized and characterized by elemental analysis, IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction. X-ray crystallographic data of 1 revealed that pydc exhibits two different coordinaton modes that play a key role in the construction of the 3-D crystal network including Ag–carboxylate clusters in which close Ag–Ag distances exist. The magnitudes of close Ag–Ag interactions in second-order energy (E2) have been revealed by natural bond orbital analysis performed with single point energy calculation using the experimental geometry of 1. Furthermore, the luminescent properties of 1 show strong fluorescence with two emission maxima in the visible region. Also, 1 has antifungal activity on Candida albicans (MIC value, 4 μg mL?1) and good antibacterial activity on micro-organisms (MIC value, 64–256 μg mL?1). 相似文献
103.
《Journal of Coordination Chemistry》2012,65(24):4259-4270
One nonlinear and one linear trinuclear copper(II) complex [Cu3(dien)2(pdc)2CH3OH]2?·?6CH3OH (1) and [Cu3(pdc)2(CH3OH)6(H2O)4] (2) were prepared and characterized structurally, where dien is diethylenetriamine and pdc3? the trianion of 3,5-pyrazoledicarboxylic acid. Both complexes consist of 3,5-pyrazoledicarboxylato-bridged trinuclear copper(II) centers. In 1, copper(II) ions are five-coordinate in distorted square pyramids with bond angles 164.78° for Cu(1)–Cu(2)–Cu(3) and 164.51° for Cu(4)–Cu(5)–Cu(6). In 2, the three copper(II) ions are six-coordinate with elongated octahedral geometry. The trinuclear units of 1 and 2 interact through hydrogen bonds to form 3-D and 2-D supramolecular networks, respectively. Variable temperature magnetic susceptibility measurements show that 1 and 2 are antiferromagnetically coupled with J values of ?11.2 and ?13.3?cm?1. 相似文献
104.
《Journal of Coordination Chemistry》2012,65(18):2861-2875
Carboxylate and salicylic OH coordinate bonding as well as intramolecular and intermolecular hydrogen bonding of bis-3,5-diisopropylsalicylatozinc(II), [ZnII(3,5-DIPS)2], with Lewis bases were studied to determine mechanisms accounting for antioxidant reactivity of ZnII(3,5-DIPS)2. Apparent thermodynamic parameters: K eq, ΔS 0, ΔH 0, and ΔG 0 were determined for these equilibria with bonding of two molecules of dimethyl sulfoxide-d6 (DMSO) or ethyl acetate-d8 (EA) to the ZnII using NMR and FTIR. We conclude that addition of two equivalents of DMSO or EA to non-polar solutions of ZnII(3,5-DIPS)2 results in bonding of DMSO or EA to ZnII via sulfoxide or ester carbonyl oxygen atoms with ternary complex formation, leading to weakening of carboxylate and salicylic OH coordinate bonding to ZnII and strengthening intramolecular hydrogen bonding between protons of salicylic OH groups and carboxylate oxygens. Subsequent addition of two or three additional equivalents of DMSO or EA leads to intermolecular hydrogen bonding between protons of salicylic OH groups. 相似文献
105.
106.
《Journal of Coordination Chemistry》2012,65(23):3776-3792
Complexes of cerium(III), lanthanum(III) and neodymium(III) with 3,5-pyrazoledicarboxylic acid (H3pdc) were synthesized and their compositions determined by elemental analysis. To identify the binding of Ce(III), La(III) and Nd(III) with H3pdc, detailed vibrational analysis was performed comparing experimental vibrational spectra of the ligand and its Ln(III) complexes with theoretically predicted and with literature data from related compounds. Significant differences in the IR and Raman spectra of the complexes were observed as compared to spectra of the ligand. The ligand and the complexes were tested for cytotoxic activities on the chronic myeloid leukemia derived K-562, overexpressing the BCR-ABL fusion protein and the non-Hodgkin lymphoma derived DOHH-2, characterized by an overexpression of the antiapoptotic protein bcl-2 cell lines. The results indicate that the tested compounds exerted considerable cytotoxic activity upon the evaluated cell lines in a concentration dependent manner; we constructed dose-response curves and calculated corresponding IC50 values. The lanthanide complexes exhibited potent cytotoxic activity, even more than cisplatin towards K-562 and DOHH-2 cell lines. In order to elucidate some of the mechanistic aspects of the observed cytotoxic effects, we evaluated whether the established cytotoxicity of the most active complex La(H2pdc) is related to its capacity to induce cell death through apoptosis. 相似文献
107.
《Journal of Coordination Chemistry》2012,65(11):1847-1857
Three structurally diverse PbII coordination complexes, [Pb3O(OH)(4-sphth)]2(H2O) (1), [Pb(3,5-Hdhb)]H2O (2), and [Pb3(4-nphth)2(OH)2] (3) (4-H3sphth, 4-sulfophthalic acid; 3,5-H2dhb, 3,5-dihydroxybenzoic acid; 4-H2nphth, 4-nitrophthalic acid), were synthesized under hydrothermal conditions. X-ray diffraction analyses reveal that 1 is constructed from [Pb4O4] cubanes, based on which ladder-shaped structure is built via 4-H3sphth bridge. This is the first Pb4O4-containing polymer. The Pb2O2 units in 2 are bridged by two parallel 3,5-HDHB ligands along the a-axis and two other parallel 3,5-HDHB ligands along the b-axis, forming a 3-D framework. For 3, the crystal structure is built up of a layer motif consisting of corner-sharing pyramidal Pb3O units, which are linked through Pb corners to form a hexagonal unit. Each PbO6 polyhedron is connected to three polyhedra (Pb3O) via sharing an edge (two μ 3-oxygen atoms) and two faces (three μ 3-oxygen atoms), thus yielding an infinite 2-D Pb–O–Pb (3,6-net) honeycomb layer. The luminescence of 1–3 demonstrates that they may be good candidates for luminescent materials. 相似文献
108.
《Journal of Coordination Chemistry》2012,65(18):2927-2936
Two 2-D metal-organic coordination polymers, {[Ag(NH2–BPT)] · NO3} n (1) and {[Ag(BPT)] · H2O} n (2), have been synthesized via self-assembly of AgNO3 and 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (NH2–BPT) under hydrothermal conditions by controlling the reaction temperatures. Lower reaction temperature (140°C) led to formation of 1, which crystallizes in the monoclinic system, space group C2/c, a = 24.001(3), b = 15.844(2), and c = 12.981(3) Å, V = 2996.8(6) Å3, Z = 8. When the temperature was increased to 180°C, in situ deaminization of the organic ligand led to crystallization of 2 (space group P21 /n, a = 7.3106(10), b = 19.633(2), and c = 9.0596(16) Å, V = 1190.2(3) Å3, Z = 4). The NH2–BPT in 1 and BPT in 2 are μ4 tetradentate utilizing two triazolyl and two pyridyl nitrogens, generating an unusual 2-D layer, in which binuclear Ag(I) motifs and organic ligands are four-connecting nodes that inter-link in 4462 topology. Adjacent 2-D metal-organic layers are linked by a system of hydrogen bonds to form 3-D supramolecular frameworks. Strong blue fluorescence emissions are observed for 1 and 2 in the solid state at ambient temperature. 相似文献
109.
3,5-吡啶二羧酸镍配位聚合物的合成与晶体结构 总被引:2,自引:0,他引:2
采用水热法合成了3个新的3,5-吡啶二羧酸镍配位聚合物[Ni(3,5-Pydc)(H2O)4·H2O]n(1), [Ni2(3,5-Pydc)2(H2O)8·(H2O)2]n(2)和[Ni(3,5-Pydc)(H2O)2]n(3), 并通过X射线单晶衍射、FTIR及热重分析对其结构和组成进行了表征. 单晶衍射结果表明, 化合物1和2是一维折线型链状结构, 而化合物3是二维层状结构. 化合物1是由3,5-Pydc配体将中心镍离子连接起来形成的折线型一维链. 在化合物2中存在着两条各自独立的折线型一维链, 但它们的配位方式却完全相同, 每一条链都是由3,5-Pydc配体将镍离子连接而成. 而化合物3则是由3个镍离子和3个3,5-Pydc配体形成的二十元环构成的二维网格. 3个化合物分别通过链间或层间氢键作用(O-H…O)形成三维超分子结构, 化合物1和2中的客体水分子被氢键限域在超分子结构之中. 相似文献
110.
1-Alkoxy-3,5-dinitrobenzenes were nitrated to give 1-alkoxy-2,3,5-trinitrobenzenes. The reaction of the latter with guanidine
affordsN-(2-alkoxy-4,6-dinitrophenyl)guanidines, which undergo cyclization under the action of KOH to form 5-alkoxy-3-amino-7-nitro-1,2,4-benzotriazine
1-oxides.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1650–1652, September, 2000. 相似文献