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751.
Shah Alam Khan S. Monawwar Imam Aftab Ahmad Syed Hussain Basha Asif Husain 《Journal of Saudi Chemical Society》2018,22(4):469-484
Based on the core structure of Felbinac drug, three series (4a–d, 5a–d and 6a–n) of five membered heterocyclic derivatives containing three heteroatoms were designed and synthesized starting from Felbinac. In the rational design of the target molecules, the biphenyl ring along with the methylene bridge of felbinac was retained while the carboxyl group was substituted with biologically active substituents like 1,2,4-triazole, 1,3,4-thiadiazole and 1,3,4-oxadiazole, with an intent to obtain novel, better and safer anti-inflammatory agents with improved efficacy. The prepared molecules were then investigated for their anti-inflammatory, ulcerogenicity and analgesic activity in experimental animals. The tested compounds exhibited varying degrees of inflammatory activity (25.21–72.87%), analgesic activity (27.50–65.24%) and severity index on gastric mucosa in the range of 0.20–0.80 in comparison to positive control felbinac (62.44%, 68.70% and 1.5, respectively). Among all the prepared compounds, 2-(biphenyl-4-ylmethyl)-5-(4-chlorophenyl)-1,3,4-oxadiazole (6c) emerged as the most potent NSAID compound exhibiting the highest anti-inflammatory activity (72.87% inhibition) and analgesic activity (65.24%) along with the least severity index on gastric mucosa (0.20). Further, molecular docking on cyclooxygenase and in silico ADME-Toxicity prediction studies also supported the experimental biological results and indicated that 6c has a potential to serve as a drug candidate or lead compound for developing novel anti-inflammatory and analgesic therapeutic agent(s) with minimum toxicity on gastric mucosa. 相似文献
752.
Prussian Blue‐Derived Iron Phosphide Nanoparticles in a Porous Graphene Aerogel as Efficient Electrocatalyst for Hydrogen Evolution Reaction
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Dr. Narendra Kumar Alam Venugopal Shuli Yin Yinghao Li Dr. Hairong Xue Dr. You Xu Prof. Xiaonian Li Dr. Hongjing Wang Prof. Liang Wang 《化学:亚洲杂志》2018,13(6):679-685
Tailoring of new hydrogen evolution reaction (HER) electrocatalyst with earth abundant elements is important for large scale water splitting and hydrogen production. In this work, we present a simple synthetic method for incorporating iron phosphide (FeP) particles into three‐dimensional (3D) porous graphene aerogel (GA) structure. The FeP formed in porous 3D GA (FeP/GA) is derived from electroactive Fe hexacyanoferrate (FeHCF). The advantage of incorporating FeP, in the porous 3D graphene network enables high accessibility for HER. As synthesized FeP/GA catalyst shows good electrocatalytic activity for HER in both acidic and alkaline solutions. The developed method can be useful for synthesizing metal hexacyanoferrate derived mono/bimetal phosphide catalyst in porous 3D graphene aerogels. 相似文献
753.
In this paper we have studied the effects of temperature dependent fluid properties such as density, viscosity and thermal conductivity and variable Prandtl number on unsteady convective heat transfer flow over a porous rotating disk. Using similarity transformations we reduce the governing nonlinear partial differential equations for flow and heat transfer into a system of ordinary differential equations which are then solved numerically by applying Nachtsheim–Swigert shooting iteration technique along with sixth-order Runge–Kutta integration scheme. Comparison with previously published work for steady case of the problem were performed and found to be in very good agreement. The obtained numerical results show that the rate of heat transfer in a fluid of constant properties is higher than in a fluid of variable properties. The results further show that consideration of Prandtl number as constant within the boundary layer for variable fluid properties lead unrealistic results. Therefore, modeling thermal boundary layers with temperature dependent fluid properties Prandtl number must treated as variable inside the boundary layer. 相似文献
754.
Dibyendu Mahato Rahla Naghma Mohammad Jane Alam Shabbir Ahmad 《Molecular physics》2013,111(21):3104-3111
This article reports electron impact ionisation cross sections for platinum-based drugs viz., cisplatin (H6N2Cl2Pt), carboplatin (C6H12N2O4Pt), oxaliplatin (C8H14N2O4Pt), nedaplatin (C2H8N2O3Pt) and satraplatin (C10H22ClN2O4Pt) complexes used in the cancer chemotherapy. The multi-scattering centre spherical complex optical potential formalism is used to obtain the inelastic cross section for these large molecules upon electron impact. The ionisation cross section is derived from the inelastic cross section employing complex scattering potential–ionisation contribution method. Comparison is made with previous results, where ever available and overall a reasonable agreement is observed. This is the first attempt to report total ionisation cross sections for nedaplatin and satraplatin complexes. 相似文献
755.
Effects of bi-kappa distributed electrons on dust-ion-acoustic shock waves in dusty superthermal plasmas
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The basic properties of dust-ion-acoustic (DIA) shock waves in an unmagnetized dusty plasma (containing inertial ions, kappa distributed electrons with two distinct temperatures, and negatively charged immobile dust grains) are investi- gated both numerically and analytically. The hydrodynamic equation for inertial ions has been used to derive the Burgers equation. The effects of superthermal bi-kappa electrons and ion kinematic viscosity, which are found to modify the basic features of DIA shock waves significantly, are briefly discussed. 相似文献
756.
A new design approach for a three-step modified signed-digit (MSD) adder is presented that can be optically implemented using binary logic gates. The proposed scheme depends on encoding each MSD digits into a pair of binary digits using a two-state and multi-position encoding scheme. The proposed design algorithm depends on constructing the addition truth table of binary-coded MSD numbers and then using Karnaugh map to achieve output minimization. The optical binary logic gates are obtained by simply programming the decoding masks of a shadow-casting-based optical logic gate system. The proposed scheme results in a simple, compact, and efficient optical binary gate-based parallel addition system. 相似文献
757.
Triinu Visnapuu Alina D. Zamfir Cristina Mosoarca Michaela D. Stanescu Tiina Alamäe 《Rapid communications in mass spectrometry : RCM》2009,23(9):1337-1346
Pseudomonas syringae pathovars possess multiple levansucrases with still unclear specific roles for bacteria. We have cloned and expressed three levansucrase genes, lsc1, lsc2 and lsc3, from P. syringae DC3000 in Escherichia coli. Levansucrases synthesize a high molecular weight fructan polymer, levan, from sucrose and in the case of some levansucrases, fructooligosaccharides (FOS) with potential prebiotic effects are also produced. The ability of purified Lsc3 protein of DC3000 to synthesize FOS was tested using prolonged incubation time and varied concentrations of sugar substrates. Thin‐layer chromatography (TLC) analysis of reaction products disclosed formation of FOS from both sucrose and raffinose, revealing a new catalytic property for P. syringae levansucrases. In order to analyze Lsc3‐produced FOS in underivatized form, we optimized a novel method recently introduced in carbohydrate research, based on fully automated chip‐based nanoelectrospray ionization (nanoESI) high‐capacity ion trap mass spectrometry (HCT‐MS). Uding chip‐based nanoESI MS in negative ion mode, FOS, with degrees of polymerization up to five, were detected in reaction mixtures of Lsc3 with sucrose and raffinose. For confirmation, further structural analysis by tandem mass spectrometry (MS/MS) employing collision‐induced dissociation at low energies was performed. To validate the method, commercial inulin‐derived FOS preparations Orafti®P95 and Orafti®Synergy1, which are currently used as prebiotics, were used as controls. By chip‐based nanoESI HCT‐MS, similar FOS distribution was observed in these reference mixtures. Thereby, the obtained data allowed us to postulate that FOS produced by the Lsc3 protein of P. syringae DC3000 may be prebiotic as well. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
758.
The semileptonic decay width of heavy baryons such as (Λ
b
→ Λcev) has been estimated in the framework of a nonrelativistic field theoretic quark model where four component quark field
operators along with a harmonic oscillator wave function are used to describe translationally invariant hadronic states. The
present estimation does not make an explicit use of heavy quark symmetry and has a reasonable agreement with the experimentally
measured decay width, polarisation ratio and form factors with the harmonic oscillator radii and quark momentum distribution
inside the hadron as free parameters. 相似文献
759.
760.
The medium modification of vector meson properties in hot/dense hadronic matter and its role in explaining the CERES/NA45
dilepton data at different centralities are discussed. 相似文献