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31.
S. P. Purohit K. C. Mathur 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):173-177
In this paper we report a study on the elastic scattering of electrons by lithium and sodium atoms in the presence of circularly
polarized resonant laser field within the framework of the two-state rotating wave approximation. The effect of laser on projectile
electrons is described by Volkov states. The frequency of the laser field is chosen to match with the 2s–3p (3s–3p) transition
frequency in lithium (sodium) atoms. The total and differential elastic cross sections with single photon exchange are calculated
for intermediate energies (50–150 eV) and laser intensity (107–1011 W cm-2).
An erratum to this article can be found online at http://dx.doi.org/.
An erratum to this article can be found at 相似文献
32.
N-Methylaminothioformyl-N'-phenylhydroxylamine forms a 1:2 (metal:ligand) greenish yellow complex with cobalt(II). This complex has maximum absorption at 470 nm with a molar absorptivity of 1.65 x 10(4) 1.mole(-1).cm(-1). Beer's law is obeyed over the concentration range 6 x 10(-6)-6 x 10(-5)M. The effect of diverse ions is described. 相似文献
33.
Narinder Sing S. B. Mathur 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-3):169-175
Abstract Anode slimes obtained from the electrolytic refining of copper contain selenium and tellurium in the form of selenides and tellurides of metals, e.g., copper and silver. The slimes were treated with sulfur under vacuum; selenides and tellurides decomposed to give selenium and tellurium in metallic form which condensed on a cooler zone. Various parameters studied were temperature, time, sulfur addition, briquetting pressure, and fineness of sulfur added. The X-ray diffraction studies carried out on treated and then on untreated slime proved the reaction of sulfur with selenide and telluride of copper to give copper sulfide, selenium, and tellurium. Sulfurization at around 475°C for 60 min gives optimum recoveries. 相似文献
34.
A series of hexachloronadimides containing phosphine oxide in the backbone were synthesized by the reaction of bis(3-amino
phenyl) methyl phosphine oxide (BAP) with pyromellitic dianhydride (PMDA)/3,3’,4,4’-benzophenone tetracarboxylic acid dianhydride
(BTDA)/2,2-bis(3,4-dicarboxy phenyl) hexafluoropropane dianhydride (6F) and hexachloronadic anhydride in glacial acetic acid/acetone.
Structural characterisation of the resins was carried out by infrared, nuclear magnetic resonance spectroscopy and elemental
analysis. Thermal characterisation of uncured resin was done by differential scanning calorimetry and thermogravimetric analysis.
The decomposition temperature of uncured resins were above 310±10°C with T
max 330±10°C in nitrogen atmosphere. Char yield at 800°C ranged from 37–42%.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
35.
The electrochemical oxidation of ethyl 3-oxo-3-phenyl-2-phenylhydrazonopropionate has been studied in the pH range 3.0–11.0 at a pyrolytic graphite electrode by linear and cyclic sweep voltammetry, coulometry and spectral studies. The results indicate that the 2 e−, 2 H+ oxidation of this compound gives phenol and ethyl 3-phenyl-2,3-dioxopropionate as the major products of electrooxidation. 相似文献
36.
JPC – Journal of Planar Chromatography – Modern TLC - The lipophilic character of phytol derivatives has been studied using reverse-phase planar chromatographic procedures.... 相似文献
37.
S. D. Dogmane R. K. Singh D. D. Bajpai J. N. Mathur 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(3):477-482
Extraction of U(VI) from HNO3, HCl and HClO4 media using cyanex-272 (bis[2,4,4 trimethyl pentyl] phosphinic acid)/n-dodecane has been carried out. In the case of HNO3 and HClO4 media, the distribution ratio (D) value first decreases and then increases, whereas from HCl medium it first decreases and then remains constant with increase in H+ ion concentration. At lower acidities, U(VI) was extracted as UO2(HA2)2 by an ion exchange mechanism, whereas at higher acidities as UO2(NO3)2
.2(H2A2) following a solvation mechanism. The D for U(VI) by cyanex-272, PC-88A and DEHPA at low acidities follows the order cyanex-272 > PC-88A > DEHPA. Also, cyanex-272 was found to extract U(VI) more efficiently than TBP at 2M HNO3. The effect of diluents on the extraction of U(VI) by cyanex-272 followed the order cyclohexane > n-dodecane > CCl4 > benzene. The loading of U(VI) into cyanex-272/n-dodecane from 2M HNO3 has shown that at saturation point, cyanex-272 was 78% loaded. No third phase was observed at the saturation level. The stripping of U(VI) from the loaded organic phase was not possible with water, it was poor with acetic acid and sodium acetate but quantitative with oxalic acid, ammonium carbonate and sodium carbonate. 相似文献
38.
Gnanasekar Rani Sarnaik Jayula S. Joseph N. C. Kadwad V. B. Mathur Anupam 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):71-76
Journal of Radioanalytical and Nuclear Chemistry - We describe a simple, user friendly two-step radioimmunoassay (RIA) based on antibody coated tubes for the measurement of free triiodothyronine in... 相似文献
39.
The ability of the back-fill and the host rock materials to take up radioisotopes like 241Am, 85,89Sr and 137Cs has been examined as a function of contact time, pH, amount of sorbent, sorbate concentration, and the presence of complementary cations. A batch technique using actual borehole water from the granite formation has been utilized. In general, the uptake of nuclides by bentonite is much higher than that with granite. The sorption order of nuclides on bentonite is Am>Cs>Sr. The presence of complementary cations, Na+, K+, Ca2+ and Mg2+ depresses the sorption of Cs and Sr on bentonite. The sorption data have been interpreted in terms of Freundlich and Langmuir isotherm equations. Utilizing the Langmuir isotherm equation, the monolayer capacity, V
m
,and the binding constant, K, have been evaluated. The change in free energy for the sorption of nuclides on bentonite has also been calculated. 相似文献
40.
Nanocrystalline zirconium carbonitride (Zr‐C‐N) and zirconium oxide (ZrO2) films were deposited by chemical vapor deposition (CVD) of zirconium‐tetrakis‐diethylamide (Zr(NEt2)4) and ‐tert‐butyloxide (Zr(OBut)4), respectively. The films were deposited on iron substrates and characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). The Zr‐C‐N films show blue, golden brown or bronze colours, with colour stability depending upon the precursor composition (pure metal amide or mixed with Et2NH). The deposition temperature showed no pronounced effect on the granular morphology of the Zr‐C‐N films. The XRD data of the films correspond to the formation of carbonitride phase whereas the XPS analyses revealed a strong surface oxidation and incorporation of oxygen in the film. The films deposited using a mixture of Zr(NEt2)4 and Et2NH showed higher N content, better adhesion and scratch resistance when compared to films obtained from the CVD of pure Zr(NEt2)4. Subject to the precursor composition and deposition temperature (550‐750 °C), the microhardness values of Zr‐C‐N films were found to be in the range 2.11‐5.65 GPa. For ZrO2 films, morphology and phase composition strongly depend on the deposition temperature. The CVD deposits obtained at 350 °C show tetragonal ZrO2 to be the only crystalline phase. Upon increasing the deposition temperature to 450 °C, a mixture of tetragonal and monoclinic modifications was formed with morphology made up of interwoven elongated grains. At higher temperatures (550 and 650 °C), pure monoclinic phase was obtained with facetted grains and developed texture. 相似文献