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971.
New films of iron complex with 4,7-bis(2-aminophenyl)-methylaminosulfonylphenyl)-1,10-phenanthroline (APP) and 5-amino-1,10-phenanthroline (AP) are prepared on the electrode surface of In–Sn oxide conducting glass (ITO) by electrochemical oxidation. The thickness (Φ) of the films prepared on the ITO can be controlled by the number of cycles of the potential scan. The resulting film-coated electrodes show well-defined reversible vol-tammograms corresponding to the redox reaction of the Fe(II/III) complexes in 0.1 M NaClO4 acetonitrile (AN), a mixture of butylene carbonate (BC) and propylene carbonate (PC) and poly2-hydroxyethylmethacrylate gel containing BC and PC. The electron transfer processes within the films can be treated apparently as diffusional processes characterized by the rate constants of the apparent diffusion coefficient (Dapp). The value of Dapp increase from 1.0 × 10?9 to 1.6 × 10?8 cm2 sec?1 as the Fe complex concentration (CFe) increases from 0.06 to 1.04 M for the [Fe(AP)3] complex film (Φ=0.80 μm) in 0.2 M NaClO4/AN solution. The Dapp value for the [Fe(APP)3) complex film (CFe = 0.19 M , Φ= 0.78 μm) is 3.5 × 10?9 cm2 sec?1 in 0.2 M NaClO4/AN solution. The Dapp values of the [Fe(AP)3] complex film in the PC + BC mixture and gel containing 1.0 M NaClO4 were smaller than those obtained in AN solution by an order of magnitude. The dependence of the apparent formal potential of the Fe(II/III) redox reaction for the [Fe(AP)3] complex film on the activity of NaClO4 supporting electrolyte in AN shows that Na+ moves preferentially across the polymer/solution interfaces during the redox reaction. The Fe(II/III) redox reaction of the Fe complex films shows reversible electrochromic response between red and colorless. 相似文献
972.
Masahiro Kurokawa Hidemasa Yamaguchi Yuji Minoura 《Journal of polymer science. Part A, Polymer chemistry》1979,17(7):2253-2262
Cationic copolymerization of l-menthyl vinyl ether (l-MVE) with indene (IN) was carried out in several solvents with BF3OEt2 as catalyst at 0°C. The solvents used in this study were selected toluene (Tol), chloroform (CHCl3), chlorobenzene (BzCl), 1,2-dichloroethane (EtCl2), and nitrobenzene; (BzNO2)/Tol = 65/35 mixture solvent. l-Methyl residue, which is an optically active side chain of copolymer produced by cationic copolymerization, was removed with dry hydrogen bromide gas by ether cleavage reaction. The copolymer [vinyl alcohol(VA)–lN], produced by the ether cleavage reaction, also showed optical rotation. From this result, therefore, it was concluded that asymmetric induction takes place in the copolymer main chain. The efficiency of asymmetric induction was determined by the measurement of optical rotation of VA–IN copolymer after the ether cleavage reaction. The efficiency of asymmetric induction in the copolymer main chain developed from the variation on polymerization solvents; the order was Tol > EtCl2 > BzCl > CHCl3 > BzNO2/Tol (65/35) mixture solvent. 相似文献
973.
Masahiro Kawamura Miwako Higashi 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(1):11-15
The magnetic circular dichroism (MCD) spectra of indazolinone, isatine, and 3-iminoisoindolinone and the induced circular dichroism (ICD) spectra of the inclusion complexes with β- or γ-cyclodextrins (CDs) have been measured. The spectra are interpreted by results of the ZINDO calculations. In the presence of cyclodextrin, the OH indazolinone tautomer is main structure that is consistent with that in the DMSO solution. The structures of the inclusion complexes are very different because of the scale of the cavity of cyclodextrin or position of quinone in molecules. 相似文献
974.
A palladium-catalyzed CO(2)-recycling reaction has been developed. Reaction of 4-methoxycarbonyloxy-2-butyn-1-ols with phenols, carried out in the presence of a palladium catalyst, produces phenoxy-substituted cyclic carbonates by way of a pathway involving a CO(2) elimination-fixation. A variety of propargylic alcohols and phenols participate in these reactions which yield cyclic carbonates with high efficiencies. Stereoselective construction of trans-cyclic carbonates is achieved by using nonsymmetric substrates. Highly enantioselective reactions occur when (S)-BINAP is used as a ligand. Reaction of 4-phenoxycarbonyloxy-2-butyn-1-ol in the presence of the palladium catalyst yields the corresponding cyclic carbonates via a three-component decomposition-reconstruction process. 相似文献
975.
Kunio Miki Masahiro Yama Yasushi Kai Nobutami Kasai 《Journal of organometallic chemistry》1982,239(2):417-428
The molecular structure of a three-coordinate palladium(II)-styrene complex, [Pd(η5-C5H5)(PEt3)(styrene)]BF4 has been determined by means of X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c, with four formula units in a cell of dimensions: a 10.229(3), b 11.262(3), c 18.760(5) Å and β 103.77(2)°. The structure was solved by the heavy atom method, and refined by the least-squares procedure to R = 0.050 for 3635 observed reflections. The palladium atom is surrounded by the cyclopentadienyl group, the triethylphosphine ligand and the olefinic bond of styrene in the cationic complex. In the palladiumstyrene bonding, the olefinic bond is inclined by 77.3° to the coordination plane defined by the Pd and P atoms and the center of the cyclopentadienyl ring (PdC(1) 2.176(6), PdC(2) 2.234(5) and C(1)C(2) 1.369(8) Å). 相似文献
976.
We have applied cavity ring-down spectroscopy to a kinetic study of the reaction of NO3 with CH3I in 20-200 Torr of N2 diluent at 298 K. The rate constant of the reaction of NO3 + CH3I was determined to be (4.1 +/- 0.2) x 10(-13) cm3 molecule(-1) s(-1) in 100 Torr of N2 diluent at 298 K and is pressure-independent. This reaction may significantly contribute to the formation of reactive iodine compounds in the atmosphere. 相似文献
977.
Yasuhiro Fuma Masahiro Ebihara 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):m284-m289
In diaquatetra‐μ‐acetamidato‐κ4N:O;κ4O:N‐dirhodium(II,III) hexafluorophosphate, [Rh2(C2H4NO)4(H2O)2]PF6, and diaquatetra‐μ‐acetamidato‐κ4N:O;κ4O:N‐dirhodium(II,III)hexafluorophosphate dihydrate, [Rh2(C2H4NO)4(H2O)2]PF6·2H2O, the cations and anions lie on inversion centers. Diaquatetra‐μ‐propionamidato‐κ4N:O;κ4O:N‐dirhodium(II,III) hexafluorophosphate dihydrate, [Rh2(C3H6NO)4(H2O)2]PF6·2H2O, and diaquatetra‐μ‐butyramidato‐κ4N:O;κ4O:N‐dirhodium(II,III) hexafluorophosphate, [Rh2(C4H8NO)4(H2O)2]PF6, crystallize with two crystallographically independent complexes that lie on inversion centers. In all of the structures, the dirhodium units are hydrogen bonded to one another. The hydrogen‐bonded networks vary with the alkyl substituents. 相似文献
978.
Nakamura T Suzuki M Ishihara M Ohana T Tanaka A Koga Y 《Langmuir : the ACS journal of surfaces and colloids》2004,20(14):5846-5849
Photolysis of perfluoroazooctane with diamond films led the chemical modification of the surface to introduce perfluorooctyl functional groups, confirmed by means of Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and time-of-flight secondary ion mass spectrometry measurements. Diamond films modified with fluorine moieties showed improved frictional property and reduction of surface energy, as evaluated by contact angle to water, compared with a pristine diamond film. The contact angle and friction coefficient of chemically modified diamond film are 118 degrees and 0.1, respectively. The results of the value of the contact angle depending on irradiation times are consistent with those of the F/C ratio of fluorinated diamond films by monitoring with XPS. 相似文献
979.
Nobuyuki Tanaka Chie Okabe Kenji Sakota Tuyoshi Fukaminato Tsuyoshi Kawai Masahiro Irie Alexander Goldberg Shinichirou Nakamura Hiroshi Sekiya 《Journal of Molecular Structure》2002,616(1-3):113-118
The fluorescence excitation and dispersed fluorescence spectra of the open-ring isomer of 1,2-bis(3-methyl-2-thienyl)perfluorocyclopentene have been measured in a supersonic free jet. No vibronic structure has been observed in the excitation spectrum. The intensity of fluorescence gradually increases with the excitation energy in the 25,500–28,700 cm−1 region, indicating that the geometry of the molecule substantially changes upon photoexcitation. The dispersed fluorescence spectrum is anomaly Stokes-shifted with respect to the excitation energy, suggesting that the S2(1B) state is initially excited followed by rapid internal conversion from the S2(1B) to S1(2A) state. The fluorescence is due to the S1(2A)–S0(1A) transition. Density functional theory calculations at the B3LYP/6-31G** level have been carried out to investigate stable conformations responsible for the observed spectra. 相似文献
980.
Kazuhisa Murata Megumu Inaba Masahiro Saito Isao Takahara Naoki Mimura 《Reaction Kinetics and Catalysis Letters》2003,80(1):39-44
The stability of an Fe/Al2O3 catalyst in the methane decomposition in the presence of O2/CO2 was found to be improved by the addition of Mg into the catalyst (Mg/Fe=1/1 wt ratio), probably due to suppression of carbon
deposition even under CH4/ O2/CO2 (80/10/5 vol. ratio) conditions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献