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111.
The dependence of the metal oxidation rate on the current density and temperature of joint destruction in sodium chloride was studied. It is established that the dependence of the oxidation rate of copper is linear and generally do not differ from the dependencies established at individual oxidation of copper in the solution of sodium chloride with concentration 46.5% wt. In contrast to the oxidation rate of copper, the oxidation rate dependence of cadmium has extreme character and the oxidation rate of cadmium at its joint oxidation of copper increased in 2-3 times indicating that the mutual influence of electrodes at the electrochemical process with alternating current. Thus, the obtained dependences can predict operating electrolysis parameters a obtain copper-cadmium oxide system of the given composition. 相似文献
112.
在KNO3底液下,用线性扫描阳极溶出伏安法同时测定了乌药样品中铜、铅、镉3种金属的含量.结果表明,在最佳实验条件下,铜、铅、镉的峰电位分别为0.067、-0.45和-0.64V(vs ScE);铜、铅、镉金属离子的质量浓度在0-0.8 mg·L-1范围内,呈现良好的线性关系,相关系数分别为0.991 3、0.990 5... 相似文献
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114.
Matthew D. Lowther William F. Wacholtz Joel T. Mague 《Journal of chemical crystallography》2001,31(6):295-300
The luminescent heteroleptic Cd(II) complex bis (-1,2-benzenedithiolato)-1 kS, 1:2 k
2
S 2 kS, 1:2 k
2
S-bis[(1,10-phenanthroline-k
2
N
1, N
1)cadmium], [Cd2(C6H4S2)2(C12H8N2)2], containing benzenedithiolate (bdt) and 1,10-phenanthroline (phen) has been synthesized and found to have the dinuclear formulation [Cd(bdt)(phen)]2. The complex crystallizes in the space group P21/n with a = 10.3400(4), b = 11.5110(4), c = 13.6230(5) Å, and = 106.828(2)°. The dinuclear complex has crystallographically imposed centrosymmetry with one S atom of the bdt ligand bridging the Cd atoms in an asymmetric fashion (Cd–S = 2.5743(5) and 2.6817(5) Å) while the second S atom is bound in a terminal mode (Cd–S = 2.4955(5) Å). The mean interplanar spacing between the phen ligand and the phenyl ring of the bdt ligand is 3.291 Å while that between the phen ligands of adjacent molecules is 3.363 Å, suggesting the presence of both intra- and intermolecular -stacking. The complex is emissive in the solid state at room temperature (em = 569 nm) with a luminecsent lifetime of 369 ns. The unstructured emission is believed to be a ligand-to-ligand –* charge transfer transition. 相似文献
115.
The CdS nanoparticles whose structure is similar to a strong electrolyte were synthesized by the colloidal chemical method. The CdS nanoparticles with Cd2+-rich surface are capped by the electrically neutral ligand of 2,2-bipyridine (bpy), and the counterion, BPh4
-, is adsorbed around the particle as balance charge. The donation from 2,2-bipyridine at 2-position to the Cd2+-rich surface of the CdS nanoparticles was characterized by X-ray photoelectron spectroscopy (XPS). These CdS nanoparticles can redisperse in pyridine (py) or DMF, and have high stability. The determination of electroconductivity and the electrophoresis deposition in dilute solution containing the CdS nanoparticles further prove the rationality of the above electrolyte structure of the CdS nanoparticles. 相似文献
116.
117.
本文报道几种不对称类卟啉镉(Ⅱ)配合物的合成及其结构表征,并对其电子吸收光谱特性进行了研究。结果表明,这类配合物的0-0跃迁在λmax>690nm有一个允许跃迁的强吸收带,且随π电子数及取代基的不同有着明显差别;在强极性溶剂中,该类配合物可发生H聚集;将跃迁能量、振子强度等性质与取代基Hammett常数进行线性相关,揭示了取代基效应对0-0跃迁的影响规律。 相似文献
118.
Sakharam B. Tayade Datta Markad Avinash S. Kumbhar Andrea Erxleben Debamitra Chakravarty 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(8):1084-1090
Two new one‐dimensional (1D) coordination polymers (CPs), namely catena‐poly[[[aquacadmium(II)]‐bis(μ‐4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione)] bis(perchlorate) dihydrate], {[Cd(C14H10N6O2)2(H2O)](ClO4)2·2H2O}n or {[Cd(BPG)2(H2O)](ClO4)2·2H2O}n, 1 , and catena‐poly[[lead(II)‐bis(μ‐4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione)] bis(perchlorate) dihydrate], {[Pb(C14H10N6O2)2](ClO4)2·2H2O}n or {[Pb(BPG)2](ClO4)2·2H2O}n, 2 , have been synthesized using bipyridine–glycoluril (BPG; systematic name: 4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione), a urea‐fused tecton, in a mixed‐solvent system. The CdII ion in 1 is heptacoordinated and the PbII ion in 2 is hexacoordinated, with the CdII ion adopting a pentagonal bipyramidal geometry and the PbII ion adopting a distorted octahedral geometry. Both CPs form infinite linear chain structures which are hydrogen bonded to each other leading to the formation of three‐dimensional supramolecular network structures. Topological analysis of CPs 1 and 2 reveals that the structures exhibit 1D chain‐like arrangements in an AB–AB sequence and shows platonic uniform 2‐connected uninodal topologies. Furthermore, a comparative analysis of a series of structures based on the BPG ligand indicates that the size of the metal ion and the types of counter‐ions used have a great influence on the resulting frameworks and properties. 相似文献
119.
120.
内蒙风化煤对镉离子溶液的吸附行为 总被引:5,自引:0,他引:5
本文利用内蒙风化煤[1,3]作吸附剂对镉离子溶液中的镉的吸附性能、特征和机理进行探索,以利内蒙风化煤的深度开发利用。1 实验内蒙风化煤(腐植酸含量高达41 3%)。空气中风干研细后,过80目筛。用3CdSO4·8H2O和H2SO4配制含Cd(Ⅱ)酸性溶液[4],镉含量采用AA 670原子吸收分光光度法(日本岛津)测定。吸附实验采用静态分析方法。准确称取一定量的风化煤放入干燥的250ml锥形瓶中,加入25ml一定浓度的含镉溶液,在室温下连续振荡2h,静置0 5h,过滤,分析滤液中的镉含量。取6g内蒙风化煤于250ml磨口锥形瓶中,移入25ml1000m… 相似文献