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121.
We explore new implications for the mu=0 hypothesis and show that the decay rate for η→3π0 is in remarkable agreement with the experiment. 相似文献
122.
123.
Journal of Mathematical Chemistry - The exact analytic expressions of the autocorrelation function and Husimi distribution function for a Morse oscillator wave packet have been derived and we use... 相似文献
124.
Avinash S. Bansode Supriya More S. V. Bhoraskar V. L. Mathe 《Surface and interface analysis : SIA》2015,47(1):22-29
The paper presents an improved method of depositing nanocrystalline thin films of Fe‐doped TiO2 to be used as a reusable cyclic photocatalyst for degrading the organic pollutants. The technique of electron cyclotron resonance plasma‐enhanced chemical vapor deposition was employed with titanium tetra‐isopropoxide (C12H28O4Ti) and ferrocene (C10H10Fe) as precursors of Ti and Fe, respectively. Optical emission spectroscopy was used to identify the reactive species, to determine the electron temperature and the ion density during deposition. The films were characterized using optical absorption and photoluminescence spectra, whereas the morphological analysis was carried out with scanning electron microscopy. Strong adhesion of the deposited films with the substrate ruled out any possibility of TiO2 particles being leached out. It was confirmed by observing the degradation rate of the same film repeatedly. Cyclic use of the film for the catalytic reactions thus makes the process much user friendly for the water treatment. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
125.
Prashant Gahtori Rahul Pandey Vinod Kumar Surajit Kumar Ghosh Aparoop Das Jun Moni Kalita Supriya Sahu Anil Prakash Divya Ranjan Bhattacharyya 《Journal of Chemometrics》2016,30(8):462-481
The front‐line antimalarial drugs, for example, chloroquine, mefloquine, sulfadoxine, pyrimethamine, atovaquone, and artemether, are often failing because of the worldwide spread of drug‐resistant parasites. There has been significant recent interest in virtual screening to drive innovative drug discovery and to combat resistance efforts for a wide range of diseases. In fact, virtual screening has become the “gold standard” for major pharmaceutical industries and some university groups. Therefore, we present herein a structure‐based LibDock/CHARMM modeling and a set of appropriate scoring function evaluation criteria: correlation, consensus score, correlation‐based score, generally applicable replacement for root‐mean‐square deviation using a training set of 38 phenylthiazolyl‐1,3,5‐triazines from our previous reports and followed by a ligand‐based model to identify molecular features like hydrogen‐bond acceptor, hydrogen‐bond donor, hydrophobicity, and ring aromatic (RA) using Catalyst HipHop/HypoGen module. Next, TOPKAT module was applied to predict ADME‐Tox properties. The combined structure/ligand‐based approaches inadvertently arrived at a conserved Arg122 binding site from reliable LigScore1_dreiding top scoring function and are subsequently attributed to reserve important interactions and combat mutational drug resistance. The best pharmacophore model suggested that 1 hydrogen‐bond acceptor, 2 hydrophobicities, and 1 ring aromatic feature with good sensitivity at 0.50, specificity at 0.66, enrichment at 1.60, and accuracy at 0.50. Finally, good pharmacokinetics, metabolic stability, and toxicity endpoints were predicted in the comparison of proguanil and cycloguanil. These druggability insights are useful for researchers to deliver more effective, safer, both wild‐type and resistance‐compromised, and more economical dihydrofolate reductase inhibitors in the near future. 相似文献
126.
A noisy version of independent component analysis (noisy ICA) is applied to simulated and real functional magnetic resonance imaging (fMRI) data. The noise covariance is explicitly modeled by an autoregressive (AR) model of order 1. The unmixing matrix of the data is determined using a variant of the FastICA algorithm based on Gaussian moments. The sources are estimated using the principle of maximum likelihood by modeling the source densities as asymmetric exponential functions. Effect of dimensionality reduction on the effective noise covariance used, accuracy of the obtained mixing matrix and degree of improvement in estimating fMRI sources are investigated. The primary conclusions after using this method of evaluation are as follows: (a) weighting matrix estimates are similar for noisy and conventional ICA in the realm of typical fMRI data, and (b) source estimates are improved by 5% (as measured by the correlation coefficient) in realistic simulated data by explicitly modeling the source densities and the noise, even when just a simple white noise model is used. 相似文献
127.
Supriya Biswas 《Journal of organometallic chemistry》2007,692(14):2897-2902
Rate constants for the nucleophilic substitution reactions of imidazolide (IZ−) and benzimidazolide (BIZ−) ions with 4-Cr-Z and 5 in MeOH at 25 °C are reported and Hammett ρ values are evaluated to be 1.50 ± 0.10 and 1.51 ± 0.08 for 4-Cr-Z-IZ− and 4-Cr-Z-BIZ− reactions, respectively. The comparable reactivity and also almost identical ρ values for these reactions indicate that there is no difference in sensitivity towards electronic effects due to slightly bigger size of BIZ− over IZ− and bond formation at the transition states are equally progressed. The higher ρ values for these reactions compared to those with a wide range of nucleophiles may arise mainly due to lower polarity of the solvent MeOH which enhances the requirement for stabilization of the negative charge in the transition state by the Z-substituents. 相似文献
128.
The phase behaviors, interfacial composition, thermodynamic properties and structural characteristics of water-in-oil microemulsions under varied molar ratio of water to surfactant (omega) at 303 K and also by varying temperatures at a fixed omega(=40) by mixing with 1-pentanol and decane or dodecane in absence and presence of sodium chloride have been studied by the method of dilution. The surfactants used were cetyl pyridinium chloride (CPC), sodium dodecyl sulfate (SDS) and polyoxyethylene (23) lauryl ether (Brij-35). The compositions of 1-pentanol and the surfactant at the interfacial region, the distribution of 1-pentanol between the interfacial region and the continuous oil phase, and the effective packing parameter (P(eff)) at the threshold level of stability have been estimated. The thermodynamics of transfer of 1-pentanol from the continuous oil phase to the interface have been evaluated. The structural parameters viz. radii of the droplet (R(e)) and the waterpool (R(w)), effective thickness of the interfacial layer (d(I)), average aggregation numbers of surfactants (N (s)) and the cosurfactant (1-pentanol) (N (a)) and the number of droplets (N(d)) have also been estimated. The prospect of using these w/o microemulsions for the synthesis of nanoparticles with small size, have been discussed in the light of the radii of the droplet, and waterpool, the extent of variation of effective thickness of the droplet under varied molar ratio of water to surfactant and temperature. An attempt has been made to rationalize the results in a comprehensive manner. 相似文献
129.
The activity of light-activatable ("caged") compounds can be temporally and spatially controlled, thereby providing a means to interrogate intracellular biochemical pathways as a function of time and space. Nearly all caged peptides contain photocleavable groups positioned on the side chains of key residues. We describe an alternative active site targeted strategy that disrupts the interaction between the protein target (SH2 domain, kinase, and proteinase) and a critical amide NH moiety of the peptide probe. 相似文献
130.
The high degree of virulence and potential for development of a pandemic strain of the H5N1 avian flu has resulted in wide interest in characterization of the various genes of the H5N1 virus genome. We have considered for our analysis all 173 available complete sequences, as of February 2006, of the neuraminidase gene, which is the target of the most effective treatment regimen comprising the inhibitors oseltamivir and zanamivir. We have used a 2D graphical representation of the neuraminidase RNA sequences of H5N1 strains to identify a few distinct structural motifs. The H5N1 strains were split into two main classes: strains that were benign to human beings in the years up to 1996 and the period 1999-2002 and strains that were highly pathogenic to humans in the periods 1997 and 2003 to present. Comparisons with earlier H1N1 pandemic and epidemic strains have also been made to understand the current status of the gene. Our findings indicate that the base composition and distribution patterns are significantly different in the two periods, and this may be of interest in studying mutational changes in such viral genes. 相似文献