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141.
Felix Birkelbach Markus Deutsch Stylianos Flegkas Franz Winter Andreas Werner 《国际化学动力学杂志》2019,51(4):280-290
A method for deriving kinetic models of gas–solid reactions for reactor and process design is presented. It is based on the nonparametric kinetics (NPK) method and resolves many of its shortcomings by applying tensor rank-1 approximation methods. With this method, it is possible to derive kinetic models based on the general kinetic equation from any combination of experiments without additional a priori assumptions. The most notable improvements over the original method are that it is computationally much simpler and that it is not limited to two variables. Two algorithms for computing the rank-1 approximation as well as a tailored initialization method are presented, and their performance is assessed. Formulae for the variance estimation of the solution values are derived to improve the accuracy of the model identification and to provide a tool for diagnosing the quality of the kinetic model. The methods effectiveness and performance are assessed by applying it to a simulated data set. A Matlab implementation is available as Supporting Information. 相似文献
142.
Oriňák Andrej Arlinghaus Heinrich Frank Vering Guido Justinová Martina Oriňáková Renáta Turčániová L’udmila Halama Maroš 《平面色谱法杂志一现代薄层色谱法》2003,16(1):23-27
JPC – Journal of Planar Chromatography – Modern TLC - Two interfaces have been tested for coupling thin-layer chromatography (TLC) with time-of-flight secondary-ion mass spectrometry... 相似文献
143.
THE USE OF SPIN LABEL OXIMETRY IN THE STUDY OF PHOTODYNAMIC INACTIVATION OF CHINESE HAMSTER OVARY CELLS 总被引:1,自引:0,他引:1
Spin label oximetry has been used to study the effects of photosensitizer hematoporphyrin on oxygen consumption in Chinese hamster ovary cells. These measurements demonstrate that, in the presence of the sensitizer, there occurs (i) an increase in total oxygen consumption during irradiation and (ii) a decrease in oxygen consumption following irradiation. These results are attributed to the effects of photosensitized oxygen consumption and decreased cellular respiration due to cell inactivation. Thus the inhibition of oxygen consumption after irradiation was shown to correlate with decreased cell survival measured in cell culture experiments. Possible mechanisms of inactivation and extensions of the oximetric approach are discussed. 相似文献
144.
145.
Lucas Ueberricke Ioana Ciubotaru Farhad Ghalami Felix Mildner Dr. Frank Rominger Prof. Dr. Marcus Elstner Prof. Dr. Michael Mastalerz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(50):11634-11642
Five di- and tetracyano-substituted pyrene-fused pyrazaacenes were synthesized and studied as potential electron acceptors in the solid state. Single crystals of all compounds were grown and the crystal packing studied by DFT calculations (transfer integrals and reorganization energies) to get insight into possible use for semiconducting charge transport. 相似文献
146.
147.
Heinrich Lang Bettina Lühmann Roy Buschbeck 《Journal of organometallic chemistry》2004,689(22):3598-3603
A straightforward method for the preparation of metallo carbosiloxanes of type Si(OCH2CH2CH2SiMe2[OCH2PPh2M(CO)n])4 (n = 3, M = Ni, 7a; n = 4, M = Fe, 7b; n = 5: M = Mo, 7c; M = W, 7d), Si(OCH2CH2CH2SiMe[OCH2PPh2Ni(CO)3]2)4 (8) and Me2Si(OCH2CH2CH2SiMe[OCH2PPh2Ni(CO)3]2)2 (11) is described. The reaction of Si(OCH2CH2CH2SiMeXCl)4 (1: X = Me, 2: X = Cl) or Me2Si(OCH2CH2CH2SiMeCl2)2 (9) with HOCH2PPh2 (3) produces Si(OCH2CH2CH2SiMe2(OCH2PPh2))4 (4), Si(OCH2CH2CH2SiMe(OCH2PPh2)2)4 (5) or Me2Si(OCH2CH2CH2SiMe(OCH2PPh2)2)2 (10) in presence of DABCO. Treatment of the latter molecules with Ni(CO)4 (6a), Fe2(CO)9 (6b), M(CO)5(Thf) (6c: M = Mo; 6d: M = W), respectively, gives the title compounds 7a-7d, 8 and 11 in which the PPh2 groups are datively bound to a 16-valence-electron metal carbonyl fragment.The formation of analytical pure and uniform branched and dendritic metallo carbosiloxanes is based on elemental analysis, and IR, 1H, 13C{1H}, 29Si{1H} and 31P{1H} NMR spectroscopic studies. In addition, ESI-TOF mass spectrometric studies were carried out. 相似文献
148.
A series of Fe-S and Fe-Se cubane clusters containing all four combinations of the general formula [Fe(4)X(4)(Y-CH(3))(4)](2)(-) (X = S/Se, Y = S/Se) is investigated with FTIR and Raman spectroscopy. The terminally selenolate coordinated clusters (Y = Se) are prepared by a new synthetic route. All four cluster compounds are structurally characterized by X-ray single-crystal structure determination. Infrared and Raman spectra of all compounds are presented and interpreted with normal coordinate analysis. The corresponding force fields are based on that developed for the Fe(4)S(4)-benzyl cluster (Czernuszewicz, R. S.; Macor, K. A.; Johnson, M. K.; Gewirth, A.; Spiro, T. G. J. Am.Chem. Soc. 1987, 109, 7178-7187). An empirical procedure is presented to convert Fe-S into Fe-Se force constants. Only minor changes in force constants are found upon S --> Se exchange, reflecting the similarity of the Fe-S and Fe-Se bonds. The drastic frequency shifts in the metal-ligand region observed upon substitution of sulfur by selenium are, therefore, primarily due to the corresponding mass changes. 相似文献
149.
Crawford MJ Ellern A Karaghiosoff K Mayer P Nöth H Suter M 《Inorganic chemistry》2004,43(22):7120-7126
The synthesis and characterization of the dioxouranium(VI) dibromide and iodide hydrates, UO(2)Br(2)x3H(2)O (1), [UO(2)Br(2)(OH(2))(2)](2) (2), and UO(2)I(2)x2H(2)Ox4Et(2)O (3), are reported. Moreover, adducts of UO(2)I(2) and UO(2)Br(2) with large, bulky OP(NMe(2))(3) and OPPh(3) ligands such as UO(2)I(2)(OP(NMe(2))(3))(2) (4), UO(2)Br(2)(OP(NMe(2))(3))(2) (5), and UO(2)I(2)(OPPh(3))(2)(6) are discussed. The structures of the following compounds were determined using single-crystal X-ray diffraction techniques: (1) monoclinic, P2(1)/c, a = 9.7376(8) A, b = 6.5471(5) A, c = 12.817(1) A, beta = 94.104(1) degrees , V = 815.0(1) A(3), Z = 4; (2) monoclinic, P2(1)/c, a = 6.0568(7) A, b = 10.5117(9) A, c = 10.362(1) A, beta = 99.62(1) degrees , V = 650.5(1) A(3), Z = 2; (4) tetragonal, P4(1)2(1)2, a = 10.6519(3) A, b = 10.6519(3) A, c = 24.0758(6) A, V = 2731.7(1) A(3), Z = 4; (5) tetragonal, P4(1)2(1)2, a = 10.4645(1) A, b = 10.4645(1) A, c = 23.7805(3) A, V = 2604.10(5) A(3), Z = 4, and (6) monoclinic, P2(1)/c, a = 9.6543(1) A, b = 18.8968(3) A, c = 10.9042(2) A, beta =115.2134(5) degrees , V = 1783.01(5) A(3), Z = 2. Whereas 1 and 2 are the first UO(2)Br(2) hydrates and the last missing members of the UO(2)X(2) hydrate (X = Cl --> I) series to be structurally characterized, 4 and 6 contain room-temperature stable U(VI)-I bonds with 4 being the first structurally characterized room temperature stable U(VI)-I compound which can be conveniently prepared on a gram scale in quantitative yield. The synthesis and characterization of 5 using an analogous halogen exchange reaction to that used for the preparation of 4 is also reported. 相似文献
150.
Afshin Nabiyan Johannes Bernhard Max Dr. Christof Neumann Magdalena Heiland Prof. Dr. Andrey Turchanin Prof. Dr. Carsten Streb Prof. Dr. Felix Helmut Schacher 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(68):16924-16929
An effective strategy to enhance the performance of inorganic semiconductors is moving towards organic-inorganic hybrid materials. Here, we report the design of core–shell hybrid materials based on a TiO2 core functionalized with a polyampholytic (poly(dehydroalanine)-graft-(n-propyl phosphonic acid acrylamide) shell (PDha-g-PAA@TiO2). The PDha-g-PAA shell facilitates the efficient immobilization of the photosensitizer Eosin Y (EY) and enables electronic interactions between EY and the TiO2 core. This resulted in high visible-light-driven H2 generation. The enhanced light-driven catalytic activity is attributed to the unique core–shell design with the graft copolymer acting as bridge and facilitating electron and proton transfer, thereby also preventing the degradation of EY. Further catalytic enhancement of PDha-g-PAA@TiO2 was possible by introducing [Mo3S13]2− cluster anions as hydrogen-evolution cocatalyst. This novel design approach is an example for a multi-component system in which reactivity can in future be independently tuned by selection of the desired molecular or polymeric species. 相似文献