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991.
《Journal of Coordination Chemistry》2012,65(21):3932-3944
Four transition metal coordination compounds, {[Co(PPDA)(H2O)2]}n (1), {[Ni(HPPDA)2]}n (2), {[Cd(PPDA)(H2O)]?H2O}n (3), and {Zn(HPPDA)2(H2O)4}n (4), were synthesized by assembling transition metal salts with a semirigid ligand 4-(pyridin-3-yloxy)-phthalic acid (H2PPDA) under hydrothermal conditions. The compounds have been characterized by elemental analyses, IR spectra, TGA, powder X-ray diffraction, and single-crystal X-ray crystallography. Compound 1 exhibits a three-connected 2-D layered structure, 2 shows a (3,6)-connected 2-D layered structure, 3 displays a (3,6)-connected 2-D layered framework based on binuclear units, and 4 is a mononuclear structure, connected to generate a 3-D supramolecular architecture by hydrogen bonds. Compound 2 is thermally stable up to 300 °C. The magnetic properties of 1 and photoluminescent properties of 3 and 4 have been explored. 相似文献
992.
993.
《Journal of Coordination Chemistry》2012,65(10):1622-1634
Reactions of Al(OPri)3 with LH2 =?[R′C(NYOH)CHC(R)OH] R=R′=CH3, Y =?(CH2)2 (L1H2); R =?CH3, R′ =?C6H5, Y =?(CH2)2 (L2H2); R =?R′ =?CH3, Y =?(CH2)3 (L3H2); R =?CH3, R′ =?C6H5, Y =?(CH2)3 (L4H2), in 1 : 2 molar ratio give mononuclear derivatives of aluminium AlLLH (1a–1d). Equimolar reactions of AlLLH with M(OPri)3 (M =?Al and B) yield homo- and hetero-dinuclear derivatives AlLLM(OPri)2 (M=Al=2a–2d M=B=3a–3d). Reaction of 2a with L1H2 affords AlL1L1AlL1 (4). All these derivatives have been characterized by elemental analysis, molecular weight measurements and plausible structures have been suggested on the basis of IR, NMR [1H, 13C, 27Al and 11B] spectral data and FAB-mass studies of 2b and 3b. Schiff base L1H2 and its mononuclear derivative with aluminium (AlL1L1H) have been screened for their antibacterial activity against Escherischia coli and Bacillus subtilis. 相似文献
994.
《Journal of Coordination Chemistry》2012,65(3):195-205
Abstract ESR investigation of the γ -ray irradiated Co(III) complexes have been carried out. The identification and the classification of the irradiation products on the basis of the ESR signal patterns, and the electronic and the spin states of the products are discussed. Co(III) complexes are reduced by the γ irradiation into Co(II) complexes, where the produced Co(II) ions have low spin configurations, S = ½. Authors refer to these particular spin states as hot ions. 相似文献
995.
The complex cis‐[RuIII(dmbpy)2Cl2](PF6) ( 2 ) (dmbpy = 4, 4′‐dimethyl‐2, 2′‐bipyridine) was obtained from the reaction of cis‐[RuII(dmbpy)2Cl2] ( 1 ) with ammonium cerium(IV) nitrate followed by precipitation with saturated ammonium hexafluoridophosphate. The 1H NMR spectrum of the RuIII complex confirms the presence of paramagnetic metal atoms, whereas that of the RuII complex displays diamagnetism. The 31P NMR spectrum of the RuIII complex shows one signal for the phosphorus atom of the PF6– ion. The perspective view of each [RuII/III(dmbpy)2Cl2]0/+ unit manifests that the ruthenium atom is in hexacoordinate arrangement with two dmbpy ligands and two chlorido ligands in cis position. As the oxidation state of the central ruthenium metal atom becomes higher, the average Ru–Cl bond length decreases whereas the Ru–N (dmbpy) bond length increases. The cis‐positioned dichloro angle in RuIII is 1.3° wider than that in the RuII. The dihedral angles between pair of planar six‐membered pyridyl ring in the dmbpy ligand for the RuII are 4.7(5)° and 5.7(4)°. The observed inter‐planar angle between two dmbpy ligands in the RuII is 89.08(15)°, whereas the value for the RuIII is 85.46(20)°. 相似文献
996.
《Journal of Coordination Chemistry》2012,65(5):513-522
Three new coordination polymers {[Ni(bte)2(NCO)2](H2O)} n (1), {[Ni(bte)2(N3)2](H2O)} n (2) and {[Ag(bte)2](NO3)} n (3) (bte?=?1,2-bis(1,2,4-triazol-1-yl)ethane) were synthesized and characterized by X-ray crystallography, IR and thermogravimetric analysis. The coordination geometry of the Ni(II) atom is distorted octahedral, coordinated equatorially by four nitrogen atoms from four triazole rings of four symmetry-related bte ligands, and axially by two nitrogen atoms from two isocyanate anions in 1 and azide anions in 2, respectively. The structures of 1 and 2 are both polymeric, with 18-membered spiro-fused rings and each 18-membered ring involving two inversion-related bte molecules. The coordination geometry of the Ag(I) atom in 3 is distorted tetrahedral, formed by four nitrogen atoms from four triazole rings of four symmetry-related bte ligands. Each bte ligand links two Ag(I) atoms and forms a two-dimensional undulated (4,4) network in 3. 相似文献
997.
Caterina Fraschetti Matthias C. Letzel Marlene Paletta Jochen Mattay Maurizio Speranza Antonello Filippi Massimiliano Aschi Alexander B. Rozhenko 《Journal of mass spectrometry : JMS》2012,47(1):72-78
The effect of cyclochirality of rccc‐2,8,14,20‐tetra‐n‐decyl‐4,10,16,22‐tetra‐O‐methylresorcin[4]arene (C) on the enantiodiscrimination of a number of chiral bidentate and tridentate aromatic and aliphatic biomolecules (G) has been investigated by nano‐electrospray ionization (nano‐ESI)‐Fourier transform ion cyclotron resonance mass spectrometry. The experimental approach is based on the formation of diastereomeric proton‐bound [C·H·G]+ complexes by nano‐ESI of solutions containing an equimolar amount of quasi‐enantiomers (C) together with the chiral guest (G) and the subsequent measurement of the rate of the G substitution by the attack of several achiral and chiral amines. In general, the heterochiral complexes react faster than the homochiral ones, except when G is an aminoalcoholic neurotransmitter whose complexes, beyond that, exhibit the highest enantioselectivity. The kinetic results were further supported by both collision‐induced dissociation experiments on some of the relevant [C2·H·G]+ three‐body species and Density functional theory (DFT) calculations performed on the most selective systems. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
998.
999.
A novel zinc(Ⅱ) complex, Zn(IBT) 2 (1, HIBT=5-(4-((1H-imidazol-1-yl)methyl)phenyl)-2H-tetrazole) has been synthesized with Zn(NO3)2·6H2O, 4-(imidazol-1-ylmethyl)benzonnitrile (IBN) and NaN 3 by the hydrothermal method, and characterized by elemental analysis, IR and single-crystal X-ray diffraction. Crystallographic data for 1:C22H18N12Zn, Mr=515.85, orthorhombic, Pbcn, a=16.0567(15), b=9.5316(9), c=14.6107(14) , V=2236.1(4) 3 , Z=4, D c=1.532 g/cm3 , μ=1.138 mm-1 , F(000)=1056, R=0.0350 and wR=0.0888 for 1438 observed reflections (I > 2σ(I)) and the goodness-of-fit S=1.002 on F2 . The crystal structural analysis revealed that complex 1 exhibits a rare two-dimensional homochiral wave-like layer structure. In addition, the photoluminescence of complex 1 was studied in the solid state at room temperature together with its theoretical analysis. 相似文献
1000.
Shengwen Wang 《Crystal Research and Technology》2008,43(8):894-898
To explore the possibility of obtaining the metal‐organic frameworks (MOFs) bearing the 2‐bromo‐1,4‐benzenedicarboxylate ligand, one new Mn(II) and one Co(II) coordination polymers, [Mn(HL)2(bipy)2·2H2O]·bipy ( 1 ) and [Co(L)(bpe)] ( 2 ) (bipy=4,4′‐bipyridine; bpe=1,2‐bis(4‐pyridyl)ethene) were synthesized and characterized by elemental analysis and X‐ray diffraction analysis. Compounds 1 exhibits one‐dimensional coordination chains, which are further connected to form two dimensional supramolecular networks through hydrogen bonding interactions. Compound 2 presents a two‐fold interpenetrating two‐dimensional layer structure. The 2‐bromo‐1,4‐benzenedicarboxylate anion exhibits different coordination modes in the two complexes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献