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141.
The synthesis
of conducting polymers based on m-nitroaniline, m-chloroaniline and m-aminophenol
by aniline initiated ammonium peroxydisulfate oxidation, has been attempted.
The IR spectra of the polymers have been studied. Thermogravimetric analysis
of the conducting polymers has been followed using a computer analysis method
LOTUS PACKAGE, developed by us for assigning the degradation mechanism. A
number of equations have been used to evaluate the kinetic parameters. The
mechanism of degradation of the conducting polymers has been explained on
the basis of their kinetic parameters. 相似文献
142.
With a view to investigate the oxidation behaviors of cetyltrimethylammonium dichromate on multifunctional groups, some arylthioureas were subjected to oxidation, both in neutral and in acidic conditions. In neutral conditions, the products were found to be a mixture of corresponding urea and isonitrile. In acidic conditions, the products were corresponding ureas only. A probable mechanism was proposed for the formation of the product, wherein the first step involves coupling of –NH2 and –SH of one molecule to the –NH2 and –SH of another molecule, respectively, which is followed by removal of nitrogen and sulfur. The microwave irradiation resulted in great yield of isonitrile than urea in neutral conditions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
143.
A green approach is reported for the synthesis of cysteine-functionalized zinc oxide nanoparticles using potato extract as a nontoxic and economical reducing agent. The cysteine-functionalized nanoparticles were used as a support for enzyme immobilization. The structural morphology, crystallinity, and surface functionalization were characterized by scanning electron microscopy, X-ray diffraction, and infrared spectroscopy, respectively. Spherical nanoparticles from 150 to 200?nm were used to evaluate the immobilization efficiency for urease through covalent attachment on the glutaraldehyde-activated amino group of cysteine. In comparison to the unmodified nanoparticles, 62.9% enzyme loading with 72.45% of enzyme specific activity was recovered which was 56% higher than on bare zinc oxide nanoparticles. The point of addition of cysteine during the nanoparticle synthesis had a direct effect on the immobilization efficiency. The immobilized enzyme-specific activity was reduced to 34.32% when cysteine was added following the nanoparticle synthesis. With a facile synthesis procedure and significant immobilization efficiency, cysteine-functionalized zinc oxide nanoparticles were shown to be suitable for various clinical and industrial applications. 相似文献
144.
P. G. Shetty S. K. Sahu R. A. Takale M. Swarnkar N. Karunakara G. G. Pandit 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(3):611-615
The outdoor and indoor environmental gamma dose rates in air have been measured in several parts of Udupi district, Karnataka, India using thermoluminescent dosimeters (TLDs). The outdoor annual gamma dose values varies in the range 0.49–1.17 mGy/year with mean 0.75 ± 0.18 mGy/year. Similarly indoor annual gamma dose varies in the range 0.51–1.10 mGy/year with mean 0.74 ± 0.13 mGy/year. The mean values of indoor and outdoor gamma dose rates were 84 and 86 nGy/h respectively with indoor to outdoor dose ratio of 1.02. 相似文献
145.
146.
Keith A. Earle Laxman Mainali Indra Dev Sahu David J. Schneider 《Applied magnetic resonance》2010,37(1-4):865-880
Methods of statistical geometry are introduced which allow one to estimate, on the basis of computable criteria, the conditions under which maximally informative data may be collected. We note the important role of constraints which introduce curvature into parameter space and discuss the appropriate mathematical tools for treating curvature effects. Channel capacity, a term from communication theory, is suggested as a useful figure of merit for estimating the information content of spectra in the presence of noise. The tools introduced here are applied to the case of a model nitroxide system as a concrete example, but we stress that the methods described here are of general utility. 相似文献
147.
Labanya Bhattacharya Smruti R. Sahoo Sagar Sharma Sridhar Sahu 《International journal of quantum chemistry》2019,119(18):e25982
We report a density functional theory study of the effect of electron-withdrawing groups such as –F, –CN, –NO2 on the geometrical, optoelectronic, intramolecular charge transfer (ICT), and photovoltaic properties of (E)-1,2-bis(5-alkyl-[2,3′-bithiophene]-2′-yl)ethene (TVT-T) based donor-acceptor (D-A) copolymers with different acceptor units, that is, benzo[c][1,2,5]thiadiazole, benzo[c][1,2,5]oxadiazole, and benzo[c][1,2,5]selenadiazole. The computed optical absorption spectra of the designed compounds lie in the visible and near-infrared regions. Of all the studied copolymers, -CN substituted and Se-based compound displays the lowest HOMO-LUMO (E H - L) gap and optical band gap (E opt). The exciton binding energy (E b) is found to be smaller for O-incorporated compounds and -CN substituted copolymer as well, inferring more ICT. The electron-hole coherence concentrated over the D-A units is nearly the same for -CN and -NO2 substituted compounds, but larger in -F derivatives, indicating weak electron-hole coupling in the formers. Comparatively larger dipole moment (6.421 Debye-9.829 Debye) and charge transfer length (D CT) (1.976 Å-3.122 Å) for -CN derivatives lead to enhanced ICT properties. The designed donors yield good hole mobilities (0.127-6.61 cm2 V−1 s−1) and the predicted power conversion efficiencies are calculated to be as high as ~6%-7% for –CN and –NO2 substituted compounds. 相似文献
148.
Ba2Zn2Fe12O22 was synthesized by solid state reaction technique. The temperature and frequency dependent electrical properties and complex impedance spectroscopy were analysed. Complex modulus formalism shows the existence of high resistance and small capacitance of the material for the short range relaxation. The presence of non-Debye type relaxation is revealed from Nyquist plots and enabled to separate the contribution from bulk and grain boundary effect in the material. Further, the ac electrical conductivity of the material was well agreed with the Jonscher's universal power law. 相似文献
149.
Dr. Syed Meheboob Elahi Dr. Mukul Raizada Pradip Kumar Sahu Prof. Dr. Sanjit Konar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):5858-5870
Design, synthesis, and applications of metal–organic frameworks (MOFs) are among the most salient fields of research in modern inorganic and materials chemistry. As the structure and physical properties of MOFs are mostly dependent on the organic linkers or ligands, the choice of ligand system is of utmost importance in the design of MOFs. One such crucial organic linker/ligand is terpyridine (tpy), which can adopt various coordination modes to generate an enormous number of metal–organic frameworks. These frameworks generally carry physicochemical characteristics induced by the π-electron-rich (basically N-electron-rich moiety) terpyridines. In this minireview, the construction of 3D MOFs associated with symmetrical terpyridines is discussed. These ligands can be easily derivatized at the lateral phenyl (4′-phenyl) position and incorporate additional organic functionalities. These functionalities lead to some different binding modes and form higher dimensional (3D) frameworks. Therefore, these 3D MOFs can carry multiple features along with the characteristics of terpyridines. Some properties of these MOFs, like photophysical, chemical selectivity, photocatalytic degradation, proton conductivity, and magnetism, etc. have also been discussed and correlated with their frameworks. 相似文献
150.
Marappan Dharani Basudeb Sahu Chakrakodi S. Shastry 《Central European Journal of Physics》2014,12(10):755-766
We present a systematic study of the conditions for the generation of threshold energy eigen states and also the energy spectrum generated by two types of locally periodic delta potentials each having the same strength λV and separation distance parameter a: (a) sum of N attractive potentials and (b) sum of pairs of attractive and repulsive potentials. Using the dimensionless parameter g = λV a in case (a) the values of g = g n , n = 1, 2, …, N at which threshold energy bound state gets generated are shown to be the roots of Nth order polynomial D 1(N, g) in g. We present an algebraic recursive procedure to evaluate the polynomial D 1(N, g) for any given N. This method obviates the need for the tedious mathematical analysis described in our earlier work to generate D 1(N, g). A similar study is presented for case (b). Using the properties of D 1(N, g) we establish that in case (a) the critical minimum value of g which guarantees the generation of the maximum possible number of bound states is g = 4. The corresponding result for case (b) is g = 2. A typical set of numerical results showing the pattern of variation of g n as a function of n and several interesting features of the energy spectrum for different values of g and N are also described. 相似文献