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61.
通过水热法合成得到了一个包含四核镉(Ⅱ)的基于2-丙基-4,5-二甲酸咪唑和4,4-联吡啶的配位聚合物[Cd2(HPIDC)2(bpy)(H2O)2](1)。X-射线单晶衍射分析结果表明:配合物1属单斜晶系,结晶在c2/c空间群中,晶胞参数为:a=1.936 6(4)nm,b=1.504 1(3)nm,c=2.200 4(5)nm,β=94.990(4)°,V=6.385(2)nm3,Z=8,1.393 mm-1,F(000)=3 216,Dc=1.684 g.cm-3,R1=0.045 8,wR2=0.108 9。通过链间的O-H…O氢键作用,形成了三维的超分子结构。固体荧光测试表明:配合物1在427 nm处发射出较强的荧光。 相似文献
62.
63.
A new 2,2"-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)2}2"bipy] (1, bipy -- 2,2"-bipyridine), was synthesized and characterized by elemental analyses, IR, UV-vis, 1H NMR, fluorescence spectroscopy, thermo-gravimetric analysis, and X-ray single-crystal diffraction. The crystal of 1 crystallizes in triclinic, space group P1 with a = 10.4607(19), b = 11.679(2), c = 18.480(3) A, a = 98.900(2), β = 103.321(2), ), = 91.779(2), V= 2165.2(7) A3, Dc = 1.447 g/cm3, Z = 2, C42H4404N2P2S4Cd, Mr = 943.37, F(000) = 968,μ = 0.814 mm-1, the final R = 0.0536 and wR = 0.1206 for 6275 observed reflections with 1 〉 2a(/) and R = 0.0690 and wR = 0.1339 for all data. The result shows that the Cd(1) centre is five-coordinated by two N and three S atoms in a highly distorted square pyramidal configuration. The C-H'"S hydrogen bonding interactions and a set of weak intermolecular r-r stacking between adjacent aromatic rings stabilize the structure and make 1 assemble into a 1D zig-zag chain. In addition, the antibacterial activities of 1 against Escherichia coli, Bacillus subtilis and Staphylococcus bacteria were also screened by disc diffusion method. 相似文献
64.
Three isomeric metal-organic frameworks,[Cd2(X)(btc)(DMA)3]n(X = Cl(1),Br(2),I(3),H3btc =1,3,5-benzenetricarboxylic acid and DMA = N,Nˊ-dimethylacetamide),have been synthesized and characterized by elemental analysis,infrared spectra(IR),thermogravimetric(TG) analyses and single-crystal X-ray diffraction.Single-crystal X-ray analysis reveals that compounds 1–3 crystallize in the orthorhombic P212121 space group,and feature a three-dimensional(3D) extended framework containing dinuclear [Cd2(COO)3] units as the secondary building units(SBUs).Topological analysis reveals that compounds 1–3 can be simplified into a 3-connected srs topological network. 相似文献
65.
The solution-phase photodecomposition of l, l-dichloro-2,2-bis(5′-chloro-2′-methoxy-phenyl)ethylene (MPE) has been studied at an excitation wavelength of 313 nm in the presence of O2 as well as in vacuum-degassed solutions. Only two non-volatile compounds are produced: 2,5-dichloro-3-(5′-chloro-2′-methoxyphenyl)benzofuran (BFD) and a minor product which was not identified. The BFD represents approximately 90% of the total non-volatiles. The volatile products were identified as CH3Cl, CH4 and HC1, with CH3C1 being approximately 99.9 % of the total volatiles. Photolyses were carried out in C6H12 and CCI4 solvents, the same products being observed in both solvents. Variation of MPE concentration has little or no effect on the relative quantum yield of decomposition. The photodecomposition of MPE does not follow the same pathway as the photodecomposition of DDE. 相似文献
66.
Walter N. L. dos Santos Dannuza D. Cavalcante Hadla S. Ferreira Cesário F. das Virgens Aline R. Borges Marcia M. Silva 《International journal of environmental analytical chemistry》2013,93(15):1447-1452
A cloud point extraction procedure for pre-concentration and determination of cadmium and lead in drinking water using sequential multi-element flame atomic absorption spectrometry is described. 4-(2-thiazolylazo)-orcinol (TAO) has been used as complexing agent and the micellar phase was obtained using the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) and centrifugation. The conditions for reaction and extraction (surfactant concentration, reagent concentration, effect of incubation time, etc) were studied and the analytical characteristics of the method were determined. The method allows the determination of cadmium and lead with quantification limits of 0.30?µg?L?1 and 2.6?µg?L?1, respectively. A precision expressed as relative standard deviation (RSD, n?=?10) of 2.3% and 2.6% has been obtained for cadmium concentrations of 10?µg?L?1 and 30?µg?L?1, respectively, and RSD of 1.3% and 1.7% for lead concentrations of 10?µg?L?1 and 30?µg?L?1, respectively. The accuracy was confirmed by analysis of a natural water certified reference material. The method has been applied for the determination of cadmium and lead in drinking water samples collected in the cities of Ilhéus and Itabuna, Brazil. Recovery tests have also been performed for some samples, and results varied from 96 to 105% for cadmium and 97 to 106% for lead. The cadmium and lead concentrations found in these samples were always lower than the permissible maximum levels stipulated by World Health Organization and the Brazilian Government. 相似文献
67.
Satoshi Kaneco Kensuke Hayashi Hideyuki Katsumata Tohru Suzuki 《International journal of environmental analytical chemistry》2013,93(13):1381-1388
A preconcentration method by adsorption of cadmium on a niobium wire was developed for the environmental waters, followed by electrothermal atomic absorption spectrometry with a tungsten tube atomizer. After the preconcentration, the niobium wire was directly inserted into the tungsten tube atomizer. In the preconcentration (adsorption) process of cadmium, the optimal immersing time was 60?s. The effects of large amounts of concomitants on the preconcentration of cadmium were evaluated. When 103–104 fold excess of matrix elements existed in aqueous solution at pH 4 and 9, the cadmium response was profoundly affected by the matrix elements. However, the cadmium absorption signal was not significantly influenced at pH 7. Therefore, pH 7 was selected for the application into the real environmental samples. Under the optimal conditions, the detection limit (3S/N) for cadmium by the niobium wire preconcentration method was 7.0?pg?mL?1 and the relative standard deviation was 6.8%. The method with preconcentration on a niobium wire was applied to the determination of cadmium in water and proved to be sensitive, simple and convenient. Because this preconcentration method can be utilized in the in situ treatment of trace cadmium in environmental water samples, it was unnecessary to carry the water samples to the analytical work place. The technique was shown to be useful for the determination of cadmium in environmental water samples at 0.1–1?µg?L?1 levels. 相似文献
68.
Stéphane Le Gac Luca Fusaro Vincent Dorcet Bernard Boitrel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(40):13253-13253
69.
采用喷雾辅助气相沉积法在水热法合成的ZnO纳米线上沉积CdS纳米颗粒。采用X射线衍射仪(XRD)、激光拉曼仪(Raman)、扫描电镜(SEM)、透射电镜(TEM)、X射线光电子能谱分析谱(XPS)和紫外可见漫反射光谱等测试手段对复合光催化剂进行表征。结果表明,3~10 nm的CdS纳米粒子修饰在直径约为100 nm ZnO纳米线的表面。XPS和Raman表明复合材料中ZnO和CdS之间存在化学相互作用。可见光催化降解罗丹明B实验结果表明ZnO/CdS复合材料的催化性能优于单相CdS或ZnO,沉积时间为30 s合成的ZnO/CdS速率常数分别是CdS和ZnO的2.91和4.03倍,且具有较高的稳定性。ZnO/CdS复合材料光催化性能增强的可能原因为光吸收范围的拓展和光生载流子分离效率的提高。 相似文献
70.
以一种尿素的衍生物2-咪唑烷酮为溶剂,采用脲热法合成了一个新的配位聚合物[Cd(NH2bdc)(e-urea)]n(1)(H2NH2bdc为2-氨基对苯二甲酸,e-urea为2-咪唑烷酮),并对其结构和荧光性质进行了研究。单晶结构分析结果表明,标题化合物的中心镉(Ⅱ)离子分别与2-氨基对苯二甲酸根配体的羧基氧原子和溶剂氧原子配位形成七配位的变形五角双锥结构。相邻的中心镉(Ⅱ)离子通过溶剂氧原子和配体羧基基团的连接,形成无限的一维链。这些一维的链进一步通过2-氨基对苯二甲酸根配体的连接最终形成了具有一维孔道的三维框架结构。研究表明,该化合物在室温下能发出较强的蓝色荧光。 相似文献