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991.
Feng Zhang Xing Liu Jian Zhou Xian-Hong Yin Jun He 《Monatshefte für Chemie / Chemical Monthly》2011,22(1):763-768
Abstract
Two new transition-metal thiogermanates [M(dap)3]4Ge4S10Cl4 (M = Co, Ni; dap = 1,2-propanediamine) have been solvothermally synthesized and structurally characterized. The two thiogermanates are isostructural and consist of discrete Ge4S104− adamantane-like ions, free Cl− ions, and [M(dap)3]2+ cations as counterions. The Ge4S104− anion is built from corner-sharing connection of four GeS44− tetrahedra. Although some chalcogenidogermanates have been obtained by use of in situ generated transition-metal complexes as structure-directing agents under mild solvothermal conditions, their anions are usually dimeric [Ge2Q6]4− (Q = S, Se) species. The new thiogermanates are rare examples of adamantane-like (Ge4S104−) thiogermanates combined with transition-metal complexes. Their optical properties have been investigated by UV–Vis spectra. 相似文献992.
Pengfei Xiao Changli Bao Naizhong Song Cui Li Qiong Jia 《Russian Journal of Inorganic Chemistry》2011,56(7):1157-1161
In the present study, sec-nonylphenoxy acetic acid (CA100) and its mixtures with four neutral organophosphorus extractants, tri-butyl-phosphate (TBP),
2-ethylhexyl phosphonic acid di-2-ethyl ester (DEHEHP), Cyanex923, and Cyanex925 have been applied to the extraction of rare
earths. Results show that all the four mixing systems do not have evident synergistic effects on the extraction of rare earths.
The different extraction effects have been considered to the separation of rare earths. The four mixtures may be applied to
the separation of yttrium from some certain lanthanoids at proper mole fractions of CA100. 相似文献
993.
Fangzhi Huang Shikuo Li Anjian Xie Hui Zhang Yang Wang Yuhua Shen Jian Li 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(9):1635-1640
Hydroxyapatite (HAP) nanorod was synthesized by using ordered bicontinuous microemulsion, and was characterized by X-ray diffraction
spectrum, scanning electron microscopy and high-resolution transmission electron microscopy. The solubility was investigated
using ion chromatogram measurement, and was sensitively dependent on the value of pH. The capabilities to capture cadmium
ions of HAP nanorods and micro-particles from aqueous salt solution were studied, and besides, X-ray diffractometry was used
in order to characterize the mechanisms of cadmium uptake. As Cd2+ adsorption occurred, it has undergone the coprecipitation of Cd2P2O7 crystal to give multiple solids composed of HAP and Cd2P2O7 crystallites, which affected the dissolution of hydroxyapatite. During Cd2+ sorption process, solubility variations of the sediments showed a more complex pattern than previously reported. Contribution
of surface mechanisms, in association with precipitation of cadmium phosphate phases, could explain this behavior. 相似文献
994.
Rui‐Bin Liu Jian‐Jun Zhang Dr. Bo Tong Xin Liu Yang Yang Chang‐Gong Meng 《无机化学与普通化学杂志》2011,637(2):269-275
Reactions between CoO, ZnCl2 (or ZnBr2), and molten citric acid (Hcit) led to the formation of two 3d‐3d heterometallic coordination frameworks: [ZnCo(Hcit)Cl] ( 1 ) and [ZnCo(Hcit)Br] ( 2 ). X‐ray structure analyses show that both compounds 1 and 2 crystallize in the monoclinic space group P21/n [ 1 : a = 5.8699(5) Å, b = 17.7963(13) Å, c = 9.2152(8) Å, β = 106.806(4) °, Z = 4, V = 921.53(13) Å3; 2 : a = 5.909(3) Å, b = 17.798(8) Å, c = 9.302(5) Å, β = 106.374(7) °, Z = 4, V = 938.6(8) Å3]. The structures of the two compounds are almost the same except for the terminal halogen ligand. Both of them are 3D frameworks based on citric acid bridging ligands and a 1D backbone chain built of corner‐shared {CoO6} and {ZnO3Cl} polyhedra. Photoluminescence and thermal stabilities of the compounds were studied. 相似文献
995.
996.
以双环戊二烯和茚为原料,经D-A反应及催化加氢合成高密度烃燃料四环[9.2.1.02,10.13.8]十四烷(TDTD).采用裂解器及色质联用进行了四环[9.2.1.02.10.1 3.8]十四烷的热裂解研究,考察了不同温度及时间对热裂解转化率的影响,结果显示,温度对转化率影响较大.分析裂解产物,推测了裂解机理,以裂解... 相似文献
997.
998.
N-[5-(Е)-1,3,4-噻二唑-2-基]-N'-芳基脲的合成、晶体结构及生物活性 总被引:2,自引:0,他引:2
为了寻找高活性的脲类细胞分裂素,通过2-氨基-5-(Е)-苯乙烯基-1,3,4-噻二唑与芳酰基叠氮化物反应,合成了11种新的含1,3,4-噻二唑环芳基脲类衍生物,其中芳酰基叠氮化物直接由芳酸、三氯氧磷与叠氮钠采用"一锅法"制得,再经加热发生Curtius重排转化为异氰酸酯.目标化合物的结构用红外光谱、核磁共振氢谱、质谱和元素分析进行了表征,并用X射线单晶衍射实验测定了化合物3g的结构.初步的生物活性测试表明,部分目标化合物在10 mg/L浓度下表现出良好的细胞分裂素活性,其中3c的活性超过50%. 相似文献
999.
1000.