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991.
Ishihara S Labuta J Šikorský T Burda JV Okamoto N Abe H Ariga K Hill JP 《Chemical communications (Cambridge, England)》2012,48(33):3933-3935
Oxoporphyrinogens (OxPs) bind water molecules at pyrrolic NH and quinonoid carbonyl groups leading to visible colour changes due to variation in the π-electronic structure of OxPs. Introduction of hydrophilic substituents at two pyrrole NH groups improves sensitivity to H(2)O, and one OxP derivative is a colorimetric indicator of trace H(2)O (~50 ppm) in THF. 相似文献
992.
Takayoshi Hirano Akira MabuchiTakashi Sugiura Hideki Minoura 《Journal of Crystal Growth》2009,311(10):3040-3043
A novel method to synthesize GaN crystals was studied by the reaction of Ga with Li3N under NH3 atmosphere. We have already reported the synthesis technique of GaN by the reaction of Ga2O3 with Li3N. However, the size of GaN crystals obtained by this method was limited to be smaller than several micrometers because of the solid phase reaction. In order to increase the size of GaN crystals, the method using liquid Ga as gallium source was studied for solid–liquid phase reaction. We found that the GaN crystals with the size of more than 100 μm were synthesized at 750 °C for 24 h under NH3 atmosphere. We propose the possible reaction mechanism as follows. Lithium amide (LiNH2) is synthesized by the reaction of Li3N with NH3 gas and then the crystal growth of GaN occurs by the reaction of Ga with LiNH2. We found that LiNH2 is a useful nitrogen source for the GaN synthesis method. 相似文献
993.
Fujii T Yamaguchi S Funahashi Y Ozawa T Tosha T Kitagawa T Masuda H 《Chemical communications (Cambridge, England)》2006,(42):4428-4430
A mononuclear copper(II)-hydroperoxo species has been generated by the reaction of Cu(I)-H2BPPA complex with dioxygen, which illustrates the enzymatic reaction process of the CuB site in the DbetaM and PHM. 相似文献
994.
Hattori Y Tanaka H Okino F Touhara H Nakahigashi Y Utsumi S Kanoh H Kaneko K 《The journal of physical chemistry. B》2006,110(20):9764-9767
Quantum sieving of activated carbon fibers (ACFs) and their fluorides was observed for H(2) and D(2) adsorption at 20 K. Fluorination reduced the slit-shaped pore width of ACFs by 0.2 nm. The activated carbon fibers can act as highly efficient quantum sieves for H(2) and D(2), because the effective size of an H(2) molecule is larger than that of a D(2) molecule due to the uncertainty principle and the molecular size difference between H(2) and D(2) is significant in the micropore space. The D(2)/H(2) selectivity of ACFs evaluated by ideal adsorption solution theory was larger than that of the fluorinated ACFs. 相似文献
995.
Hideki Kuramitz 《Analytical and bioanalytical chemistry》2009,394(1):61-69
This review provides a summary of recent works concerning electrochemical immunoassays using magnetic microbeads as a solid
phase. Recent research activity has led to innovative and powerful detection strategies that have been resulted in sensitive
electrochemical detection. Coupling of magnetic microbeads with highly sensitive electrochemical detection provides a useful
analytical method for environmental evaluation and clinical diagnostics, etc. The huge surface area and high dispersion capability
of magnetic microbeads strongly contributes towards the development of new sensitive, rapid, user-friendly, and miniaturized
electrochemical immunoassay systems. Moreover, the immunocomplexes formed on the magnetic microbead surface can be easily
detected without pretreatment steps such as preconcentration or purification, which are normally required for standard methods.
The discussion in this review is organized in two main subjects that include magnetic-microbead-based assays using enzyme
labels and nanoparticle tags.
Figure SEM image of Dynabeads M-280 (12% γ-Fe2O3 in polystyrene, diameter is 2.8 μm)
相似文献
Hideki KuramitzEmail: |
996.
Onagi H Carrozzini B Cascarano GL Easton CJ Edwards AJ Lincoln SF Rae AD 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(24):5971-5977
The conformations of two [2]rotaxanes, each comprising alpha-cyclodextrin as the rotor, a stilbene as the axle and 2,4,6-trinitrophenyl substituents as the capping groups, have been examined in solution and in the solid state, using (1)H NMR spectroscopy and X-ray crystallography, respectively. In solution, introducing substituents onto the stilbene prevents the cyclodextrin from being localized over one end of the axle. Instead the cyclodextrin moves back and forth along the substituted stilbene. In the solid state, the axles of the rotaxanes form extended molecular fibres that are separated from each other and aligned along a single axis. The molecular fibres are strikingly similar to those formed by the axle component of one of the rotaxanes in the absence of the cyclodextrin, but in the latter case they are neither separated nor all aligned. 相似文献
997.
We find the necessary and sufficient conditions for the entropy rate of the system to be zero under any system-environment Hamiltonian interaction. We call the class of system-environment states that satisfy this condition lazy states. They are a generalization of classically correlated states defined by quantum discord, but based on projective measurements of any rank. The concept of lazy states permits the construction of a protocol for detecting global quantum correlations using only local dynamical information. We show how quantum correlations to the environment provide bounds to the entropy rate, and how to estimate dissipation rates for general non-Markovian open quantum systems. 相似文献
998.
Hideki Sakurai Hisashi Sugiyama Mitsuo Kira Keiji Yamamoto 《Journal of organometallic chemistry》1982,225(1):163-170
Sixp- andm-nitrophenyl-substituted methylpolysilanes have been prepared by the reaction of nitrobenzyne with monohydromethylpolysilanes. UV spectra ofp-nitrophenylpolysilanes revealed a strong red shift compared with the parent phenylpolysilanes due to the contribution of intramolecular charge transfer to the nitro group. 相似文献
999.
This work studies numerically three-dimensional formation of a vortex array in a rotating cylindrical vessel. The formation process and the resulting equilibrium pattern are affected by pinning sites on the vessel’s bottom. 相似文献
1000.
Storage of hydrogen at 303 K in graphite slitlike pores from grand canonical Monte Carlo simulation 总被引:1,自引:0,他引:1
Kowalczyk P Tanaka H Hołyst R Kaneko K Ohmori T Miyamoto J 《The journal of physical chemistry. B》2005,109(36):17174-17183
Grand canonical Monte Carlo (GCMC) simulations were used for the modeling of the hydrogen adsorption in idealized graphite slitlike pores. In all simulations, quantum effects were included through the Feynman and Hibbs second-order effective potential. The simulated surface excess isotherms of hydrogen were used for the determination of the total hydrogen storage, density of hydrogen in graphite slitlike pores, distribution of pore sizes and volumes, enthalpy of adsorption per mole, total surface area, total pore volume, and average pore size of pitch-based activated carbon fibers. Combining experimental results with simulations reveals that the density of hydrogen in graphite slitlike pores at 303 K does not exceed 0.014 g/cm(3), that is, 21% of the liquid-hydrogen density at the triple point. The optimal pore size for the storage of hydrogen at 303 K in the considered pore geometry depends on the pressure of storage. For lower storage pressures, p < 30MPa, the optimal pore width is equal to a 2.2 collision diameter of hydrogen (i.e., 0.65 nm), whereas, for p congruent with 50MPa, the pore width is equal to an approximately 7.2 collision diameter of hydrogen (i.e., 2.13 nm). For the wider pores, that is, the pore width exceeds a 7.2 collision diameter of hydrogen, the surface excess of hydrogen adsorption is constant. The importance of quantum effects is recognized in narrow graphite slitlike pores in the whole range of the hydrogen pressure as well as in wider ones at high pressures of bulk hydrogen. The enthalpies of adsorption per mole for the considered carbonaceous materials are practically constant with hydrogen loading and vary within the narrow range q(st) congruent with 7.28-7.85 kJ/mol. Our systematic study of hydrogen adsorption at 303 K in graphite slitlike pores gives deep insight into the timely problem of hydrogen storage as the most promising source of clean energy. The calculated maximum storage of hydrogen is equal to approximately 1.4 wt %, which is far from the United States Department of Energy (DOE) target (i.e., 6.5 wt %), thus concluding that the total storage amount of hydrogen obtained at 303 K in graphite slitlike pores of carbon fibers is not sufficient yet. 相似文献