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421.
Subhashree Singh Suprava Sahoo Bhaskar Chandra Sahoo Manaswini Dash Sanghamitra Nayak Basudeba Kar 《Molecules (Basel, Switzerland)》2022,27(3)
The essential oil of Kaempferia galanga L. commonly known as sand ginger has increased its demand in national and international market for decades. Cinnamic acid esters like ethyl-p-methoxy cinnamate (EPMC) and ethyl cinnamate (EC) are major constituents in its essential oil. In spite of the high demand for the plant as raw material, identification of quality chemovars having high essential oil (EO) yield and constituents is still at an infant stage. With this in mind, we have evaluated the EO yield of 36 accessions from three provinces of Eastern India, which varied within a range of 0.41 ± 0.01 to 2.63 ± 0.03 v/w. Further, a total of 65 compounds were detected by gas chromatography and mass spectrometry (GC-MS) with area percentages varying from 76.16 to 97.3%. EPMC was found to be the major component in 14 accessions with area percentages varying from 10.7% to 41.1%, whereas other 22 accessions showed EC as the major constituent, varying from 16% to 29.1%. Further, a diversity study among accessions was performed by agglomerative hierarchical clustering (AHC) and principal component analysis (PCA) analysis based on the abundance of identified constituents, which categorized all 36 accessions into three clusters. Thus, the present study helps to identify quality chemovar K.g16 and K.g14 with respect to oil yield and constituents, respectively, which could be used to guide commercial cultivation and further improvement of the taxa. 相似文献
422.
The present work concerns itself with the study of the effects of Growth Rate Dispersion (GRD) in industrial crystallizers. The GRD in crystallizers is described by a model similar to the one describes axial dispersion in near plug flow reactors. From it differential and cumulative equations are developed for crystal population, crystal length, crystal area, and crystal mass. The model results have been compared with the available experimental data of sucrose crystallizer. 相似文献
423.
This work deals with the prediction of crystal size distribution (CSD) in a continuous crystallizer for size-dependent growth. Crystal growth rates are described by Abegg, Stevens, and Larson (ASL) model. Stratified Monte Carlo method has been employed to evaluate the integrals involved in the classical moment equation for prediction of CSD. The simulation results have been compared with the available experimental data of K2CO3 · 1.5 H2O crystals in a continuous crystall lizer. 相似文献
424.
Nonlinear Dynamics - Motivated by the dynamics of microscale oscillators with thermo-optical feedback, a simplified third-order model capturing the key features of these oscillators is developed,... 相似文献
425.
A plane-wave density functional theory (DFT) study on surface interactions of a cyclo-[Au(μ-Pz)]3 monolayer (denoted as T), Pz = pyrazolate, with Au(111) and Al(111) surfaces (denoted as M′) has been performed. Structural and electronic properties at the M′–T interfaces are determined from individually optimized structures of M′, T and M′–T. Results show that the gold pyrazolate trimer (T) binds more strongly on the Au(111) surface than on Al(111). Charge redistribution has been observed at both M′–T interfaces, where charge is “pushed” back towards the Au(111) surface from the trimer monolayer in Au(111)–T system, while the opposite happens in the Al(111)–T system where the charge is being pushed toward the trimer monolayer from the Al(111) surface. Considerable changes to the work function of Au(111) and Al(111) surfaces upon the trimer adsorption which arise from monolayer vacuum level shifts and dipole formation at the interfaces are calculated. The interaction between cyclo-[Au(μ-Pz)]3 with metal surfaces causes band broadening of the gold pyrazolate trimer in M′–T systems. The present study aids better understanding of the role of intermolecular interactions, bond dipoles, energy-level alignment and electronic coupling at the interface of metal electrodes and organometallic semiconductor to help design metal–organic field effect transistors (MOFETs) and other organometallic electronic devices. 相似文献
426.
Bhaskar Chakraborty Prawin Kumar Sharma Manjit Singh Chhetri 《Journal of heterocyclic chemistry》2012,49(5):1260-1265
A simple one pot and high yield efficient method is described in water for the diastereo and regioselective synthesis of some novel isoxazolidine derivatives at room temperature in a short reaction time. 相似文献
427.
Energy decomposition analysis of cation–π, metal ion–lone pair,hydrogen bonded,charge‐assisted hydrogen bonded,and π–π interactions
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Bhaskar Sharma Hemant Kumar Srivastava Gaddamanugu Gayatri Garikapati Narahari Sastry 《Journal of computational chemistry》2015,36(8):529-538
This study probes the nature of noncovalent interactions, such as cation–π, metal ion–lone pair (M–LP), hydrogen bonding (HB), charge‐assisted hydrogen bonding (CAHB), and π–π interactions, using energy decomposition schemes—density functional theory (DFT)–symmetry‐adapted perturbation theory and reduced variational space. Among cation–π complexes, the polarization and electrostatic components are the major contributors to the interaction energy (IE) for metal ion–π complexes, while for onium ion–π complexes ( , , , and ) the dispersion component is prominent. For M–LP complexes, the electrostatic component contributes more to the IE except the dicationic metal ion complexes with H2S and PH3 where the polarization component dominates. Although electrostatic component dominates for the HB and CAHB complexes, dispersion is predominant in π–π complexes.Copyright © 2015 Wiley Periodicals, Inc. 相似文献
428.
A multilayered feed-forward ANN architecture trained using the error-back-propagation (EBP) algorithm has been developed for predicting whether a given nucleotide sequence is a mycobacterial promoter sequence. Owing to the high prediction capability (97%) of the developed network model, it has been further used in conjunction with the caliper randomization (CR) approach for determining the structurally/functionally important regions in the promoter sequences. The results obtained thereby indicate that: (i) upstream region of −35 box, (ii) −35 region, (iii) spacer region and, (iv) −10 box, are important for mycobacterial promoters. The CR approach also suggests that the −38 to −29 region plays a significant role in determining whether a given sequence is a mycobacterial promoter. In essence, the present study establishes ANNs as a tool for predicting mycobacterial promoter sequences and determining structurally/functionally important sub-regions therein. 相似文献
429.
We attempt in this paper to deal with some aspects of the direct photon production phenomenon mainly in the Pb+Pb and Au+Au collisions on the basis of a model for production of the same particle species in PP collisions. The results have, thereafter, been converted to those for a few AB/AA interactions through an appropriate mechanism. Comparison of the theoretical results obtained on the basis of model-based calculations with measured data on the relevant observables leads to a fair agreement between them. This reflects modestly the fair achievements attained by the models that are made use of in the present work. 相似文献
430.
Construction of modified inorganic mineral with controlled mineralization analogues of those produced by nature is now of
current interest for understanding the mechanism of thein vivo biomineralization processes, as well as looking for fresh industrial and technological applications. Low-molecular-weight
chiral poly-carboxylate ligands derived from naturally occurring L-α-amino acids have been used as model systems to study
the effect of molecular properties on crystal growth modification. 相似文献