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91.
LI Guo-Qinga XU Gangb ZHENG Fa-Kunb GUO Guo-Congb② a 《结构化学》2008,27(10):1275-1280
The title compounds have been respectively synthesized by solution process and solvothermal reaction, and their crystal structures were determined by X-ray diffraction method. For (CH3CH2CH2CH2NH3)6(BiI6)(I)2I3 1, it crystallizes in tficlinic, space group P1^- with Mr = 2049.76, a = 8.5719(1), b = 11.7461(3), c = 15.700(1)A, V = 1451.4(1)A^3, Z = 1, Dc = 2.345 g/cm^3, F(000) = 924, μ(MoKα) = 8.907 mm^-1, T = 293(2) K, the final R = 0.0655 and wR = 0.0804 for 2399 observed reflections with I 〉 2σ(I). For (NH3CH2CH2NH3)2Bi2I10 2, it crystallizes in monoclinic, space group P21/n with Mr= 1811.20, a = 8.434(4), b = 13.862(6), c = 13.362(6)A, V = 1499.9(12)A^3, Z = 2, Dc = 4.010 g/cm^3, F(000) = 1536,μ(MoKα) = 22.007 mm^-1, T = 293(2) K, the final R = 0.0584 and wR = 0.1451 for 1798 observed reflections with I 〉 2σ(I). The structures of 1 and 2 contain halobismuthate monomer and dimers, respectively. It is noteworthy that the dimers and their organic counters in 2 connect each other by N…I hydrogen bonds to form a layered structure, and the electrostatic interactions and crystal packing forces between layers give rise to the packing of the crystal. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.13 and 2.01 eV, respectively. 相似文献
92.
碱熔-氢化物发生原子荧光光谱法连续测定锑精矿中的砷、铋、硒、锡 总被引:6,自引:1,他引:5
建立了氢化物发生原子荧光光谱法测定锑精矿中砷、铋、硒、锡的方法.研究了基体及共存元素的干扰情况,实验表明,在酒石酸、硫脲-抗坏血酸存在下,适当的增加酸度可以有效地消除干扰.采用Na2O2熔解样品,用HCl酸化,无需分离基体,实现了锑精矿中砷、铋、硒、锡的连续测定,其回收率为90.6%~103.8%,检出限分别为0.35、0.20、0.65和0.35 μg/L.应用该方法分析了锑精矿样品,结果令人满意. 相似文献
93.
94.
以NaOH溶液快速沉淀BiCI3溶液制备了BiO(OH),研究了BiO(OH)对NaBH4还原芳香族硝基化合物的催化性能,考察了NaBH4用量对反应的影响.结果表明,在温和条件下BiO(OH)具有很高的催化活性和选择性.NaBH4和芳香族硝基化合物的摩尔比为1.04:1,在甲醇中室温反应2 h,芳香族硝基化合物主要被还原为氧化偶氮苯类化合物,收率80.4%~96.9%.该催化剂重复使用5次后活性没有明显下降.于120℃再生后,其活性与新制备催化剂相当. 相似文献
95.
In this paper, the effect of bismuth doping on the structural, morphological, optical and electrical properties of Cu2ZnSnS4 (CZTS) films has been investigated. The undoped and bismuth doped CZTS films (0, 0.5, 1, 1.5 and 2 mol%) were deposited on glass substrates by solution based method. The XRD result shows a significant improvement in the crystallinity of the films with increase in bismuth concentration. The Raman spectra of the films show the dominant peak at 334 cm–1 corresponding to A1 vibrational mode of CZTS kesterite phase. The FESEM micrographs of the films show an enhancement in the grain size and densification with the addition of bismuth ion concentration. The optical bandgap of the films was found to vary (1.59–1.40 eV) with the doping of bismuth ions. The I –V characteristics indicate twofold increment in the photoconductivity for the bismuth doped CZTS films under 100 mW/cm2 illumination suggesting their potential application in photovoltaic devices. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
96.
Inside Cover: Solvent‐Driven Reductive Activation of CO2 by Bismuth: Switching from Metalloformate Complexes to Oxalate Products (Angew. Chem. Int. Ed. 48/2016) 下载免费PDF全文
97.
Poly(ionic liquid)‐Mediated Morphogenesis of Bismuth Sulfide with a Tunable Band Gap and Enhanced Electrocatalytic Properties 下载免费PDF全文
Prof. Dr. Min‐Rui Gao Prof. Dr. Shu‐Hong Yu Dr. Jiayin Yuan Weiyi Zhang Prof. Dr. Markus Antonietti 《Angewandte Chemie (International ed. in English)》2016,55(41):12812-12816
Conventional polymer additives have a substantial impact on synthetic inorganic chemistry, but critical shortcomings remain; for example, low solubility in organic solvents and potential thermodynamic aggregates. Poly(ionic liquid)s have now been used as efficient additives that enable a high level control of bismuth sulfide crystals with significant size and morphological diversities. The bismuth sulfides exhibit tunable band structure as a result of the quantum size effects. Moreover, poly(ionic liquid)s are able to couple with as‐synthesized bismuth sulfides chemically and endow a modified surface electronic structure, which allows resultant products to possess outstanding electrocatalytic performance for water oxidation, although its commercial counterpart is catalytically inert. 相似文献
98.
Sequential Voltammetric Determination of Uranium,Cadmium and Lead by Using the ex situ Bismuth Film Electrode: Application to Phosphate Fertilizers 下载免费PDF全文
Cristiane L. Jost Lara M. di Martos Luis Ferraz Paulo Cícero do Nascimento 《Electroanalysis》2016,28(2):287-295
A sequential voltammetric procedure for the determination of uranium, cadmium and lead was investigated at an ex situ bismuth film electrode (BiFE). First, the adsorptive stripping voltammetry was applied to assay the U(VI)‐cupferron complex in the differential pulse mode (detection limit of 1.0 µg L?1, 200 s accumulation time). Through the manipulation of the same aliquot of the sample, efforts were made to quantify cadmium and lead by square wave anodic stripping voltammetry. Detection limits of 2.03 µg L?1 for Cd (II) and 2.43 µg L?1 for Pb (II) were calculated (100 s accumulation time). The methodology was successfully applied to phosphate fertilizer samples after open vessel wet decomposition (HNO3/H2O2). The following value ranges were evaluated: U (VI) 37.2–150 mg kg?1, Pb (II) 78.3–204 mg kg?1 and Cd (II) 44.1–71.6 mg kg?1. Validation was performed by using the standard reference materials SRM‐695 – phosphate fertilizer – and SRM‐1643e – water. 相似文献
99.
The bismuth salt of lauric (dodecanic) acidBi6O4(OH)4(C11H23COO)6 was studied earlier. This salt has layer structure (the interlaminardistance=37.50 Å), under heating this liquid-crystalline state has themesomorphic transformation, turns to the amorphous state, decomposes stepwisewith the formation of well-ordered layers of bismuth nanoparticles. DSC-curveswere used for the study of the decomposition kinetics in the area of decompositionwith small mass loss and exothermic effect (423–483 K). 相似文献
100.