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991.
Alireza Ranjbar-Motlagh 《Differential Geometry and its Applications》2008,26(3):339-345
The purpose of this paper is to generalize the Liouville theorem for functions which are defined on the complete Riemannian manifolds. Then, we apply it to the isometric immersions between complete Riemannian manifolds in order to obtain an estimate for the size of the image of immersions in terms of the supremum of the length of their mean curvature vector in a quite general setting. The proofs are based on the Calabi's generalization of maximum principle for functions which are not necessarily differentiable. 相似文献
992.
993.
Alireza Saffarzadeh 《Surface science》2006,600(20):4785-4795
We present a theory to study the temperature-dependent behavior of surface magnetization in a ferromagnetic semi-infinite crystal. Our approach is based on the single-site approximation for the s-f model. The effect of the semi-infinite nature of the crystal is taken into account by a localized perturbation method. Using the mean-field theory for the layer-dependent magnetization, the local density of states and the electron-spin polarization are investigated at different temperatures for ordinary and surface transition cases. The results show that the surface magnetic properties may differ strongly from those in the bulk and the coupling constant of atoms plays a decisive role in the degree of spin polarization. In particular, for the case in which the exchange coupling constant on the surface and between atoms in the first and second layer is higher than the corresponding in the bulk, an enhancement of surface Curie temperature and hence the spin polarization can be obtained. 相似文献
994.
Sedigheh Safari Alireza Zomorodipour Nour Amirmozaffari Morteza Daliri Choopari 《Applied biochemistry and biotechnology》2009,159(2):404-414
Hemophilia B is an X-linked recessive bleeding disorder caused by deficiency or malfunctioning of human coagulation factor
IX (hFIX). Hemophilia B patients are treated at present by infusion of plasma derived hFIX which is not always efficient,
because development of anti-hFIX antibodies (alloantibodies) in some cases inhibits the activity of the infused hFIX. The
hFIX alloantibodies are directed against γ-carboxyglutamic acid residues (Gla-domain) or protease domain in hFIX light chain.
An epitope-containing fragment of hFIX light-chain was expressed in a T7-based Escherichia coli expression system and after purification, it was used for the immunization of rabbit to develop specific antibodies anti-hFIX.
The plasma, derived from the immunized rabbit, was shown to be able to detect the normal hFIX, which indicates for the presence
of a specific anti-hFIX antibody and supporting that a bacterially expressed hFIX subfragment might be able to neutralize
the alloantibodies. Considering the importance of hFIX and its related investigations, both the produced hFIX antigen and
its corresponding antibody will play important roles for experiments dealing with the production of hFIX and studies involved
in the neutralization of the hFIX inhibitors in hFIX-related disorders and other clinical applications. 相似文献
995.
996.
Amir Koolivand Alireza Badiei Pezhman Arab Ghodsi Mohammadi Ziarani 《Journal of the Iranian Chemical Society》2016,13(7):1315-1324
A nanoporous carbon (CMK-3) was synthesized and used to adsorb 2-phenylethanol (PEA) from aqueous solutions. The characterization of CMK-3 by N2 adsorption isotherm revealed the formation of a nanoporous carbon with average pore diameter and surface area of 3.34 nm and 1268 m2 g?1, respectively. Column-like particle morphology of CMK-3 was observed from scanning electron microscope images. To evaluate the feasibility of CMK-3 as a potential PEA adsorbent, batch adsorption experiments were conducted for aqueous PEA solutions. The results showed that CMK-3 is an efficient sorbent for the separation of PEA from water. The optimized adsorbent doses were found to be 0.3 and 2.2 g L?1 for 30 and 300 mg L?1 PEA, respectively. Our studies about the effect of pH on CMK-3 adsorption capacity revealed that the adsorption capacity increased at lower pH due to the protonation of PEA. Three adsorption models, Langmuir, Freundlich and Temkin were used to describe the adsorption isotherms. Thermodynamic parameters such as ΔG 0, ΔH 0, and ΔS were also evaluated, and it was found that the sorption process was spontaneous, endothermic, and physical in nature. The adsorption kinetics was investigated in detail and the pseudo-second-order kinetic equation fitted the experimental data very well. The mechanistic study by Weber-Morris model revealed that the overall adsorption process was simultaneously governed by external mass transfer and intraparticle diffusion. Almost all (97 %) adsorbed PEA was successfully recovered into ethanol which is a common solvent in fragrance industry. CMK-3 was proved to be a promising adsorbent for the adsorption-recovery of PEA from aqueous solution. 相似文献
997.
Alireza Zarrinjahan Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Iraj Mohammadpoor-Baltork 《Journal of the Iranian Chemical Society》2016,13(8):1509-1516
Efficient epoxidation of alkenes catalyzed by tetrakis(p-aminophenyl)porphyrinatomanganese(III) chloride, [Mn(TNH2PP)Cl], supported on graphene oxide nanosheets, is reported. The catalyst, [Mn(TNH2PP)Cl]@GO, was prepared by covalent attachment of amino groups of porphyrin to carboxylic acid groups of GO. This new heterogenized catalyst was characterized by ICP, FT-IR and diffuse reflectance UV–vis spectroscopies, scanning electron microscopy and transmission electron microscopy. This catalyst was applied as an efficient and reusable catalyst in the epoxidation of alkenes with NaIO4 at room temperature, in the presence of imidazole as axial ligand. The most noteworthy advantage of [Mn(TNH2PP)Cl]@GO is its high reusability in the oxidation reactions, in which the catalyst was reused several times without significant loss of its catalytic activity. 相似文献
998.
Mohammad T. Baei A. S. Ghasemi E. Tazikeh Lemeski Alireza Soltani Niloofar Gholami 《Journal of Cluster Science》2016,27(4):1081-1096
Density functional theory calculations were performed to understand the electronic properties of C24, B12N12, B12P12, and (6, 0) BNNT interacted with N2O molecule in the presence and absence of an external electric field using the B3LYP method and 6-31G** basis set. The adsorption of N2O from O-side on the surface of (6, 0) BNNT has high sensitivity in comparison with B12N12 nano-cage. The adsorption energy of N2O (O-side) on the sidewalls of B12N12 and BNNT in the presence of an electric field are ?21.01 and ?15.48 kJ mol?1, respectively. Our results suggest that in the presence of an electric field, the B12N12 nano-cage is the more energetically notable upon the N2O adsorption than (6, 0) BNNT, C24, and B12P12. Whereas, our results indicate that the electronic property of BNNT is more sensitive to N2O molecule at the presence of an electric field than B12N12 nano-cage. It is anticipated that BNNT could be a favorable gas sensor for the detection of N2O molecule. 相似文献
999.
Naseri Amene Asghari Sarabi Ghazale Samadi Morasae Yousefi Mahdieh Ebrahimi Mahdi Moshfegh Alireza Z. 《Research on Chemical Intermediates》2022,48(3):911-933
Research on Chemical Intermediates - Photocatalytic wastewater treatment and concurrent energy production or metal ions conversion to less harmful products have great potential to address both... 相似文献
1000.
Dr. Ayan Dasgupta Yara van Ingen Michael G. Guerzoni Dr. Kaveh Farshadfar Prof. Jeremy M. Rawson Dr. Emma Richards Prof. Alireza Ariafard Prof. Rebecca L. Melen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(45):e202201422
An efficient and mild reaction protocol for the decarbonylation of isocyanates has been developed using catalytic amounts of Lewis acidic boranes. The electronic nature (electron withdrawing, electron neutral, and electron donating) and the position of the substituents (ortho/meta/para) bound to isocyanate controls the chain length and composition of the products formed in the reaction. Detailed DFT studies were undertaken to account for the formation of the mono/di-carboxamidation products and benzoxazolone compounds. 相似文献