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991.
Noha Said Bedowr Rosiyah Binti Yahya Nesrain Farhan 《Journal of Saudi Chemical Society》2018,22(3):255-260
This paper presents synthesis, structural characterization and spintronic applications of copper (II) tetradecanoate derived magnetic complexes. The complexes were prepared by a chemical reaction between [Cu2(CH3(CH2)12COO)4](EtOH)2 and 2,2′-bipyridine-4,4′-bipyridine ligands respectively. The complexes were further reacted between the product of the first reaction and 4,4′-bipyridine-2,2′-bipyridine respectively. The structural characterization techniques included elemental analysis, Fourier transformed infrared spectroscopy (FTIR), Ultra-violet–Visible (UV–Vis) spectroscopy, polarized optical microscopy, magnetic moment and thermogravimetric analysis. The structural and characterization results suggested that the synthesized complexes were binuclear and mononuclear covalent complexes of copper(II) with structural formulas [Cu2(η2-(OOCR)4](4,4′-bpy)2H2O] and [Cu(η1-(OOCR)2(2,2′-bpy) (4,4′-bpy)] respectively. 相似文献
992.
在水热条件下利用H4ddb配体合成了3个过渡金属配合物[Co2(ddb)(phen)2(H2O)6]·3H2O(1),[Co(ddb)0.5(bpy)0.5(H2O)3]n(2)和{[Ag(dpe)]·0.5(H2ddb)·H2O}n(3)(H4ddb=3,3'',4,4''-四羧基偶氮苯,bpy=4,4''-联吡啶,dpe=1,2-二(4-吡啶基乙烯)),并用元素分析、红外光谱、X射线粉末衍射、X射线单晶衍射对其进行了表征。配合物1为双核结构,基于丰富的氢键作用扩展形成三维超分子网结构。配合物2为基于钴离子通过ddb4-配体以μ4:η1,η1,η1,η1的配位模式连接而成的二维网结构。配合物3是由Ag(Ⅰ)离子与dpe配体形成的直链结构,客体分子H2ddb2-通过氢键作用将其扩展为三维超分子结构。此外还研究了配合物1~3的荧光性质和热稳定性。 相似文献
993.
Jonathan OShea Christopher S. Theile Rajat Das I. Ramesh Babu Klaus Charisse Muthiah Manoharan Martin A. Maier Ivan Zlatev 《Tetrahedron》2018,74(42):6182-6186
5′-(E)-Vinylphosphonate (VP) is an effective bioisostere of the natural 5′-monophosphate in small interfering RNAs (siRNAs). Solid-phase synthesis of VP-siRNAs requires the use of appropriately protected VP-phosphoramidites in combination with optimal oligonucleotide deprotection conditions. Addition of 3% (v) neat diethylamine to the standard aqueous ammonia deprotection conditions allows clean and rapid one-step deprotection of 5′-[O,O-bis(pivaloyloxymethyl)] (POM)-protected VP oligonucleotides, minimizing side reactions and impurities, which broadly enhances the scope of VP oligonucleotide synthesis. 相似文献
994.
V. N. Artem'eva V. V. Kudryavtsev P. I. Chupans A. V. Yakimanskii V. M. Denisov L. A. Shibaev N. G. Stepanov G. V. Lyubimova 《Russian Chemical Bulletin》1992,41(11):1979-1984
The results of a study, by thermal mass spectrometric analysis and NMR spectroscopy, of the polycondensation of H-complexes are presented from which it is possible to propose a mechanism for the reaction. It is shown that conversion of the H-complexes into polyimides takes place through the formation of intermediate zwitterions with an amino acid bond after initial separation of methanol, following which elimination of water commences in one stage to form an imide ring. The role of theortho position of the functional groups in the acid ester during the formation of the hydrogen bond is discussed.Institute of Macromolecular Compounds, Russian Academy of Sciences, 199004 St. Petersburg. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2517–2524, November, 1992. 相似文献
995.
V. N. Artem'eva V. V. Kudryavtsev P. I. Chupans T. D. Glumova G. V. Lyubimova N. A. Nikanorova 《Russian Chemical Bulletin》1993,42(2):255-258
The kinetics of thermal imidization of the H-complexes derived from the diethyl ester of 3,3,4,4-benzophenonetetracarboxylic acid (EBZP) and various diamines have been studied. A comparison of kinetic parameters obtained for the imidization of H-complexes based on ethyl or methyl esters of this acid has disclosed the differences in the behavior of each of the two H-bonds and the contribution of each bond to the mechanism of polyimide formation from the respective H-complexes.For part 5, see ref.1
Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 300–303, February, 1993. 相似文献
996.
Four new complexes have been synthesized based on the 2,4,5-trifluoro-3-methoxybenzoic acid and 4,4′-bipy of the type [R3Sn(OOCC6HF3OCH3)]2·(4,4′-bpy). All complexes were characterized by elemental, IR, 1H, 13C and 119Sn NMR spectra analyses. Complexes 1 and 4 were also characterized by X-ray crystallography. Crystal structures of 1 and 4 show that the coordination number of tin atom is five and the 2D network is connected by intermolecular C–H···O interactions. 相似文献
997.
Laura Pigani Renato Seeber Fabio Terzi Chiara Zanardi 《Journal of Electroanalytical Chemistry》2004,570(2):235-242
Electrogenerated deposits of poly[4,4′-bis(butylsulphanyl)-2,2′-bithiophene] have been characterised in the presence of different supporting electrolytes, by coupling current (charge) to microgravimetric measurements from the electrochemical quartz crystal microbalance (EQCM). The simultaneous collection of voltammetric measurements and of data relative to mass changes shows the influence exerted by the nature of the supporting electrolyte on the charge-discharge steps of both p- and n-doping processes. Interestingly, the microgravimetric data collected corresponding to the pre-peaks of both doping processes suggest the occurrence of two opposite motions of ions (ingress into and exit out from the polymer) in the relevant potential region, giving a contribution to the study of the `residual charge' phenomenon. 相似文献
998.
N. S. Karpenko V. I. Filyakova G. G. Aleksandrov V. N. Charushin 《Journal of Structural Chemistry》2005,46(5):955-959
The crystal structure of lithium 1-phenyl-4,4-difluoro-1,3-butadionate composed of-O-Li-O-bond chains was determined by XRD. In these chains, the lithium atoms, tetrahedrally coordinated with oxygen, alternate with square-bipyramidal units containing four Li-O bonds and two weak Li-F interactions. 相似文献
999.
Fabio Marchetti Claudio Pettinari Riccardo Pettinari 《Coordination chemistry reviews》2005,249(24):2909-2945
This review summarizes the literature on 4-acyl-5-pyrazolone ligands, their synthesis, characterization and coordination chemistry toward main group, transition, lanthanide and actinide metals and relevant applications of their metal complexes. 相似文献
1000.
Yueyang Zhu Cun-Fang Wang Kai Yan Ke-Dong Zhao Gui-Hua Sheng Qiqige Hu 《Journal of Coordination Chemistry》2016,69(16):2493-2499
A dicyanoamide-bridged polymeric copper(I/II) complex, [CuII(sal)(bipy)CuI(dca)2]n, was prepared by reaction of 5-methylchlorosalicylaldehyde (Hsal), 2,2′-bipyridine (bipy), sodium dicyanoamide (Nadca), and copper perchlorate in methanol. The complex was characterized by elemental analyses, infrared and electronic spectroscopy, and single-crystal X-ray determination. CuII has a square pyramidal coordination, and CuI has triangular coordination. The complex showed high urease inhibitory activity with IC50 value of 0.16 ± 0.23 μM. 相似文献