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2.
ZnO biointerfaces with serum albumin have attracted noticeable attention due to the increasing interest in developing ZnO-based materials for biomedical applications. ZnO surface morphology and chemistry are expected to play a critical role on the structural, optical, and electronic properties of albumin-ZnO complexes. Yet there are still large gaps in the understanding of these biological interfaces. Herein we comprehensively elucidate the interactions at such interfaces by using atomic force microscopy and nanoshaving experiments to determine roughness, thickness, and adhesion properties of BSA layers adsorbed on the most typical polar and non-polar ZnO single-crystal facets. These experiments are corroborated by force field (FF) and density-functional tight-binding (DFTB) calculations on ZnO-BSA interfaces. We show that BSA adsorbs on all the studied ZnO surfaces while interactions of BSA with ZnO are found to be considerably affected by the atomic surface structure of ZnO. BSA layers on the surface have the highest roughness and thickness, hinting at a specific upright BSA arrangement. BSA layers on surface have the strongest binding, which is well correlated with DFTB simulations showing atomic rearrangement and bonding between specific amino acids (AAs) and ZnO. Besides the structural properties, the ZnO interaction with these AAs also controls the charge transfer and HOMO-LUMO energy positions in the BSA-ZnO complexes. This ZnO facet-specific protein binding and related structural and electronic effects can be useful for improving the design and functionality of ZnO-based materials and devices. 相似文献
3.
Lin Jiang Pauline M.G.van Deursen Hadi Arjmandi-Tash Liubov A.Belyaeva Haoyuan Qi Jiao He Vincent Kofman Longfei Wu Valery Muravev Ute Kaiser Harold Linnartz Emiel J.M.Hensen Jan P.Hofmann Grégory F.Schneider 《中国科学:化学(英文版)》2021,(6):1047-1056
Graphene as a two-dimensional material is prone to hydrocarbon contaminations,which can significantly alter its intrinsic electrical properties.Herein,we implem... 相似文献
4.
Stelios Bekiros Samaneh Soradi-Zeid Jun Mou Amin Yousefpour Ernesto Zambrano-Serrano Hadi Jahanshahi 《Entropy (Basel, Switzerland)》2022,24(8)
This article is devoted to the determination of numerical solutions for the two-dimensional time–spacefractional Schrödinger equation. To do this, the unknown parameters are obtained using the Laguerre wavelet approach. We discretize the problem by using this technique. Then, we solve the discretized nonlinear problem by means of a collocation method. The method was proven to give very accurate results. The given numerical examples support this claim. 相似文献
5.
Muhammad Abbas Amanda M. Maceda Hamid R. Firouzi Zhifeng Xiao Hadi D. Arman Yanshu Shi Hong-Cai Zhou Kenneth J. Balkus Jr 《Chemical science》2022,13(48):14285
A new rare earth based two-dimensional coordination network and a three-dimensional metal–organic framework (MOF) have been synthesized using bicinchoninic acid (BCA) and yttrium(iii) ions. Yttrium dimer nodes are formed in the absence of a modulator, resulting in a 2D layered coordination network (Y–BCA-2D). The presence of fluorinating agents, e.g., 2-fluorobenzoic acid (2-FBA), 2,6-difluorobenzoic acid (2,6-DFBA), and perfluorohexanoic acid (PFHxA) result in μ3-F bridged metal hexaclusters (Y6F8) that form a three-dimensional MOF (Y–BCA-3D). It was found that Y3+ can break highly stable C–F bonds in aromatic and aliphatic fluorinated compounds. Single-crystal X-ray diffraction (SC-XRD) shows the presence of fluorine in the metal cluster which was confirmed by energy dispersive X-ray spectroscopy (EDS). High resolution X-ray photoelectron spectroscopy (XPS) and 19F Nuclear Magnetic Resonance (NMR) also verify the presence of metal–fluorine bonds in the cluster. The Y–BCA-3D MOF selectively adsorbs CO2 but not N2.The reaction of yttrium(iii) and linker makes a 2D metal–organic framework. The addition of fluorinated modulators result in fluorine extraction from modulators and makes a 3D-MOF. 相似文献
6.
Hooman Moradpour Mohsen Javaherian Ebrahim Namvar Amir Hadi Ziaie 《Entropy (Basel, Switzerland)》2022,24(6)
Relying on the quantum tunnelling concept and Maxwell–Boltzmann–Gibbs statistics, Gamow shows that the star-burning process happens at temperatures comparable to a critical value, called the Gamow temperature () and less than the prediction of the classical framework. In order to highlight the role of the equipartition theorem in the Gamow argument, a thermal length scale is defined, and then the effects of non-extensivity on the Gamow temperature have been investigated by focusing on the Tsallis and Kaniadakis statistics. The results attest that while the Gamow temperature decreases in the framework of Kaniadakis statistics, it can be bigger or smaller than when Tsallis statistics are employed. 相似文献
7.
This paper presents a method for the construction of a graphene paste electrode (GPE) from reduced graphene oxide (RGO). The GPE was successfully used for the determination of medetomidine. The influence of some experimental variables such as pH, supporting electrolyte, scan rate, and possible interferences were studied. Differential pulse voltammetric (DPV) peak currents of medetomidine increased linearly with its concentration in the range from 0.009 to 2.5 µM. The limit of detection (LOD) and limit of quantitation (LOQ) values for the determination of medetomidine were 2.8 and 9.2 nM, respectively. Also, for the first time, the electroreduction behavior of medetomidine was investigated. 相似文献
8.
Mahasin F. Hadi Al-Kadhemy 《Physica B: Condensed Matter》2012,407(17):3335-3338
The influence of the thickness of CdTe/n-Ge heterojunction photodetectors on I–V curves was studied experimentally and theoretically. The thicknesses of the CdTe thin films were 110, 130, 150, and 200 nm. The power intensity of illumination was 150 mW/cm2. Increasing the thickness led to an increase in photocurrent. 相似文献
9.
Karim Akbari Dilmaghani Behzad Zeynizadeh Hadi Parasajam 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):544-553
Abstract Various 3,4-dihydropyrimidin-2-(1H)-ones (DHPMs) and their sulfur derivatives were efficiently synthesized by a one-pot cyclocondensation reaction of aromatic and aliphatic aldehydes, β-dicarbonyl compounds and urea (or thiourea) in the presence of sulfuric acid immobilized on activated charcoal (133% w/w). The reactions were carried out in refluxing n-hexane-acetonitrile (2.5:0.5 mL) within 5–150 min to give 3,4-dihydropyrimidinones (or thiones) in high to excellent yields (81–97%). 相似文献
10.
A spatially intermittent polymerization (SIP) reactor has been used for determination of absolute rate constants in photo-initiated, free-radical polymerization of styrene (STY) and methyl methacrylate (MMA). Experimental data are reported in the temperature range 15-30°C and in the high molecular weight region for MMA and STY. Additional experimental data are reported at 30° C and various lower molecular weights for STY which indicate that the propagation rate constant K is independent of polymer molecular weight, and K is dependent on molecular weight, especially at low molecular weight, approaching an approximately constant value at high molecular weight. 相似文献