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91.
M. Hussain M. Hanif S. Ali S. Shahzadi M. S. Ahmad B. Mirza H. S. Evans 《Journal of the Iranian Chemical Society》2010,7(1):155-163
New organotin(IV) compounds containing the carboxylate ligand 2,3-methylenedioxybenzoic acid (HL) have been synthesized with the general formula R2SnL2 (R = Me, Et, n-Bu, Ph and n-Oct) and R3SnL (R = n-Bu). All compounds have been studied in the solution state by multinuclear NMR (1H, 13C and 119Sn) by using the non-coordinating solvent and also in solid sate by FTIR, mass spectrometry and X-ray crystallography. Spectroscopic data have shown that methylenedioxy moiety does not coordinate with tin atom and the coordination site is actually -COO group, as is proved by X-ray structure determination. The solid state structure of compound (2) has been determined by X-ray crystallography which shows that the complex (2) has distorted octahedral geometry. These complexes have been evaluated in vitro against crown gall tumor and antibacterial activity. Interesting results were noticed during the bio-activity screenings, which proved their in vitro biological potential and possible use as drugs. 相似文献
92.
Mubasher?JamilEmail author Ibrar?Hussain 《International Journal of Theoretical Physics》2011,50(2):465-472
We have investigated the accretion of phantom energy onto a 5-dimensional extreme Einstein-Maxwell-Gauss-Bonnet (EMGB) black
hole. It is shown that the evolution of the EMGB black hole mass due to phantom energy accretion depends only on the pressure
and density of the phantom energy and not on the black hole mass. Further we study the generalized second law of thermodynamics
(GSL) at the event horizon and obtain a lower bound on the pressure of the phantom energy. 相似文献
93.
Hassan Saadat 《International Journal of Theoretical Physics》2011,50(6):1769-1775
In this article we consider the cosmological model based on the holographic dark energy. We study dark energy density in Universe
with arbitrary spatially curvature described by the Friedmann-Robertson-Walker metric. We use Chevallier-Polarski-Linder parametrization
to specify dark energy density. 相似文献
94.
He RH Fujita M Enoki M Hashimoto M Iikubo S Mo SK Yao H Adachi T Koike Y Hussain Z Shen ZX Yamada K 《Physical review letters》2011,107(12):127002
We demonstrated experimentally a direct way to probe a hidden propensity to the formation of a spin-density wave in a nonmagnetic metal with strong Fermi surface nesting. Substituting Fe for a tiny amount of Cu (1%) induced an incommensurate magnetic order below 20 K in heavily overdoped La(2-x)Sr(x)CuO(4). Elastic neutron scattering suggested that this order cannot be ascribed to the localized spins on Cu or doped Fe. Angle-resolved photoemission revealed a strong Fermi surface nesting inherent in the pristine La(2-x)Sr(x)CuO(4) that likely drives this order. Our finding presents the first example of the long-sought "itinerant-spin extreme" of cuprates, where the spins of itinerant doped holes define the magnetic ordering ground state; it complements the current picture of cuprate spin physics that highlights the predominant role of localized spins at lower dopings. 相似文献
95.
Asma Rehman Muhammad Irfan Majeed Ayesha Ihsan Syed Zajif Hussain Saif-ur-Rehman Muhammad Afzal Ghauri Zafar M. Khalid Irshad Hussain 《Journal of nanoparticle research》2011,13(12):6747-6754
Abstract
A simple and environmentally benign green method is reported to decorate growing fungal hyphae with high loading of gold nanoparticles, which were initially produced using aqueous tea extract as a sole reducing/stabilizing agent. Inoculation of fungal spores in aqueous suspension of nanoparticles led to the growth of intensely red-coloured fungal hyphae due to the accumulation of gold nanoparticles. Heat treatment of these hybrid materials led to the formation of porous gold microwires. This report is thus an interesting example of using green and sustainable approach to produce nanostructured materials which have potential applications in catalysis, sensing and electronics. 相似文献96.
In this paper we consider a class of polynomials P(z) = a0+∑n v=t a v z v, t ≥ 1not vanishing in |z|k, k≥1 and investigate the dependence of max|z|=1|P(Rz)-P(rz)on max|z|=1|P(z)|, where 1 ≤ r R. Our result generalizes and refines some know polynomial inequalities. 相似文献
97.
Arshad Sadiqa Khan Majid Hussain Iqtadar 《International Journal of Theoretical Physics》2021,60(9):3631-3650
International Journal of Theoretical Physics - The use of digital contents has increased tremendously in this modern era. In fact, people spend more time on internet than ever which urged the... 相似文献
98.
Moamen S. Refat Ahmed Gaber Yusuf S. Althobaiti Hussain Alyami Walaa F. Alsanie Sonam Shakya Abdel Majid A. Adam Mohamed I. Kobeasy Kareem A. Asla 《Molecules (Basel, Switzerland)》2022,27(13)
New Cu(II), Ni(II), Co(II), and Mn(II) complexes of the gabapentin (Gpn) bidentate drug ligand were synthesized and studied using elemental analyses, melting temperatures, molar conductivity, UV–Vis, magnetic measurements, FTIR, and surface morphology (scanning (SEM) and transmission (TEM) electron microscopes).The gabapentin ligand was shown to form monobasic metal:ligand (1:1) stoichiometry complexes with the metal ions Cu(II), Ni(II), Co(II), and Mn(II). Molar conductance measurements in dimethyl-sulfoxide solvent with a concentration of 10−3 M correlated to a non-electrolytic character for all of the produced complexes. A deformed octahedral environment was proposed for all metal complexes. Through the nitrogen atom of the –NH2 group and the oxygen atom of the carboxylate group, the Gpn drug chelated as a bidentate ligand toward the Mn2+, Co2+, Ni2+, and Cu2+ metal ions. This coordination behavior was validated by spectroscopic, magnetic, and electronic spectra using the formulas of the [M(Gpn)(H2O)3(Cl)]·nH2O complexes (where n = 2–6).Transmission electron microscopy was used to examine the nanostructure of the produced gabapentin complexes. Molecular docking was utilized to investigate the comparative interaction between the Gpn drug and its four metal [Cu(II), Ni(II), Co(II), and Mn(II)] complexes as ligands using serotonin (6BQH) and dopamine (6CM4) receptors. AutoDock Vina results were further refined through molecular dynamics simulation, and molecular processes for receptor–ligand interactions were also studied. The B3LYP level of theory and LanL2DZ basis set was used for DFT (density functional theory) studies. The optimized geometries, along with the MEP map and HOMO → LUMO of the metal complexes, were studied. 相似文献
99.
Sohail Khan Aftab Hussain Ansar Mehmood Shagufta Perveen Muhammad Imran 《Natural product research》2016,30(23):2629-2636
β-Sitosterol-3-O-(6?-O-13?-octadecenoyl)-β-D-glucoside (1), a new acyl β-sitosteryl glucoside, along with three known compounds β-sitosterol-3-O-β-D-glucoside (2), β-sitosterol (3) and methyl gallate (4) have been isolated from the ethyl acetate soluble fraction of methanolic extract of Ailanthus altissima fruits. Their structures were elucidated through spectroscopic data including 2D NMR, ESI-MS, methanolysis and oxidative cleavage of double bond. Antibacterial, antifungal, cytotoxic, phytotoxic and insecticidal activities were evaluated of compound 1, crude extract and its fractions so far for the first time. Pharmacological activities results showed that n-butanol fraction was good active against Pseudomonas aeruginosa and Salmonella typhi bacteria, and moderate active against Microsporum canis fungus. Crude extract, n-butanol and aqueous fractions showed good cytotoxicity. Moreover, compound 1, extract and all fractions showed notable phytotoxicity at higher concentrations, whereas all inactive against assayed insects. 相似文献
100.
Conventional lattice Boltzmann models for the simulation of fluid dynamics are restricted by an error in the stress tensor that is negligible only for small flow velocity and at a singular value of the temperature. To that end, we propose a unified formulation that restores Galilean invariance and the isotropy of the stress tensor by introducing an extended equilibrium. This modification extends lattice Boltzmann models to simulations with higher values of the flow velocity and can be used at temperatures that are higher than the lattice reference temperature, which enhances computational efficiency by decreasing the number of required time steps. Furthermore, the extended model also remains valid for stretched lattices, which are useful when flow gradients are predominant in one direction. The model is validated by simulations of two- and three-dimensional benchmark problems, including the double shear layer flow, the decay of homogeneous isotropic turbulence, the laminar boundary layer over a flat plate and the turbulent channel flow. 相似文献