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561.
Detlef Selent Anke Spannenberg Christoph Kubis Armin Brner 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(4):398-401
A hydroxy phosphonite was found to be unstable during the catalyst preformation routine applied towards a rhodium olefin hydroformylation catalyst. C—P bond cleavage occurred when the phosphonite was reacted with [(acac)Rh(1,5‐COD)] (acac is acetyl acetate and 1,5‐COD is cycloocta‐1,5‐diene) at 80 °C and 20 bar of CO/H2. As a result, a nearly planar six‐membered ring structure consisting of two rhodium(I) cations and two bridging phosphorous acid diester anions was formed, namely bis[μ‐(4,8‐di‐tert‐butyl‐2,10‐dimethoxydibenzo[d,f][1,3,2]dioxaphosphepin‐6‐yl)oxy]‐1:2κ2P:O;1:2κ2O:P‐bis{[6‐([1,1′‐biphenyl]‐2‐yloxy)‐4,8‐di‐tert‐butyl‐2,10‐dimethoxydibenzo[d,f][1,3,2]dioxaphosphepine‐κP]carbonylrhodium(I)} toluene tetrasolvate, [Rh2(C22H28O5P)2(C34H37O5P)2(CO)2]·4C7H8. Further coordination of phosphite and of carbonyl groups resulted in 16‐electron rhodium centres. 相似文献
562.
563.
具有新颖结构的亚磷酸锌化合物的水热合成与表征 总被引:2,自引:2,他引:0
在水热体系中以二乙烯三胺为模板剂合成了结构新颖的亚磷酸锌化合物Zn(DETA)Zn2(HPO3)3.单晶X射线衍射分析结果表明,该化合物属正交晶系,Cmca空间群,晶胞参数a=1.889 25(1)nm,b=1.001 04(5)nm,c=1.630 32(8)nm,β=90°,V=3.083 3(3)nm3,Z=4,DC=1.162 Mg.m-3,最终因子R1[I>2σ(I)]=0.068 5,wR2[I>2σ(I)]=0.160 5.该化合物的结构中含有{ZnO4},{ZnO2N3}和{HPO3}基本结构单元,其中{ZnO4}和{HPO3}通过桥氧原子共顶点相互交替连接形成具有4-,8-和12-元环的无限延伸的二维层.有趣的是,{ZnO2N3}结构单元以二聚体形式{ZnODETA}2悬挂在12-元环孔道中,这种结构在亚磷酸锌中鲜有报道. 相似文献
564.
565.
566.
1,3-Bis(4-bromobutyl)-6-methyluracil reacts with diethyl 2-(dimethylamino)ethylphosphonate to form a bisquaternary ammonium
salt, whereas the reaction of 1,3-bis-(6-bromohexyl)-6-methyluracil with diethyl 2-(diethylamino)ethyl phosphate gives 1,3-bis-[(6-diethoxyphosphoryloxy)hexyl]-6-methyluracil
and 1,1,4,4-tetraethylpiperazinium dibromide.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1130–1132, June, 2000. 相似文献
567.
Two new open-framework gallium phosphites formulated as (C2N2H10)0.5Ga2(OH)(H2O)(HPO3)3(1) and (C3N2H5)2(C3N2H6)Ga8(H2O)6(HPO3)14(2) were hydrothermally synthesized in the presence of ethylenediamine(en) and imidazole as structure directing agents(SDA), respectively. Structural analyses reveal that the 3D structures of compounds 1 and 2 are both built up from the linkage of GaO6, GaO5(H2O) and HPO32? units by sharing vertices. The structure of compound 2 is constructed from well-known 4.6.12-net connecting layers in the AAAA stacking sequence, which are penetrated by the 1D Ga-O-P chains to form a 3D pillared-layered structure. 相似文献
568.
Summary Effects of column temperature and pressure on the retention behaviour of aromatic hydrocarbons were investigated in liquid and supercritical fluid chromatography by using a packed column and methanol or diethyl ether as the mobile phase. Oligomers of styrene, polysiloxane and a non-ionic detergent were separated by temperature- and pressure-gradient elution. 相似文献
569.
Solubility measurements of the gases He, Ne, Ar, Kr, Xe, H2, D2, N2, CH4, C2H4, C2H6, CF4, SF6, and CO2 in formaldehyde diethyl acetal in the range of –10 to 30°C, and a gas partial pressure of 1 atmosphere (101.32 kPa) are reported. Standard changes of thermodynamic functions for the solution process are evaluated. The scaled particle theory is used to obtain the effective Lennard-Jones 6, 12 pair potential parameters for formaldehyde diethyl acetal. Experimental solubilities values are compared with those obtained from the application of the scaled particle theory to gas liquid solubility. 相似文献
570.
Dirk Steinborn Mario Rausch Ute Baumeister Ivan Poto
k Duan Miklo Michal Dunaj-Jur
o 《无机化学与普通化学杂志》1996,622(11):1941-1945
2-(1-Methyliminoethyl)phenol ( 1 a ) reacts with diethyl zinc to give bis[2-(1-methyliminoethyl)phenolato]zinc ( 3 ) via [2-(1-methyliminoethyl)phenolato]ethylzinc ( 2 ) as an intermediate. The complex 3 is also formed in the reaction of bis(trimethylsilyl)amide zinc with 1 a . The compounds were characterized by microanalysis, NMR (1H, 13C) and IR spectroscopy. X-ray structure analysis of the compounds 2 and 3 revealed that both compounds form in the solid state dimeric species where the monomeric units are bridged via two oxygen atoms forming a planar Zn2O2 ring with tetrahedral [ZnO2NC] and trigonal-bipyramidal [ZnO3N2] coordination of the zinc atom, respectively. 相似文献