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The distortion/interaction activation strain (DIAS) analysis is a powerful tool for the investigation of energy barriers. However, setup and data analysis of such a calculation can be cumbersome and requires lengthy intervention of the user. We present autoDIAS, a python tool for the automated setup, performance, and data extraction of the DIAS analysis, including automated detection of fragments and relevant geometric parameters. © 2019 Wiley Periodicals, Inc. 相似文献
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Omar S. Ahmed Michal Malý Yoann Ladner Laurent Philibert Pavel Dubský Catherine Perrin 《Electrophoresis》2019,40(21):2810-2819
A simple, sensitive, specific, and cost‐effective analytical methodology was developed for the analysis of human plasma samples spiked with imatinib by CZE with on‐line UV detection in the context of Therapeutic Drug Monitoring. Several analytical conditions such as the ionic strength (I) and the pH of the BGE composed of citric acid and ε‐amino caproic acid were studied in regards of the presence of sodium chloride (NaCl) in plasma samples (1% m/v). Computer simulations (Simul software) were used to confirm the experimental results and to understand imatinib electrophoretic behavior in the presence of NaCl. Furthermore, the advantages of adding ACN to the sample containing NaCl to combine efficient protein precipitation and on‐line CZE stacking of imatinib were demonstrated. LOD and LOQ values of 48 and 191 ng/mL were obtained from plasma sample supernatant after protein precipitation with ACN, which is much lower than mean imatinib plasma level observed for patients treated by imatinib mesylate (about 1000 ng/mL). Good linearity was obtained in the concentration range 191–5000 ng/mL (R2 > 0.997). RSD of less than 1.68% and 2.60% (n = 6) for migration times and corrected peak areas, respectively, were observed at the LOQ. 相似文献
4.
Software aging is a phenomenon referring to the performance degradation of a long-running software system. This phenomenon is an accumulative process during execution, which will gradually lead the system from a normal state to a failure-prone state. It is a crucial challenge for system reliability to predict the Aging-Related Failures (ARFs) accurately. In this paper, permutation entropy (PE) is modified to Multidimensional Multi-scale Permutation Entropy (MMPE) as a novel aging indicator to detect performance anomalies, since MMPE is sensitive to dynamic state changes. An experiment is set on the distributed database system Voldemort, and MMPE is calculated based on the collected performance metrics during execution. Finally, based on MMPE, a failure prediction model using the machine learning method to reveal the anomalies is presented, which can predict failures with high accuracy. 相似文献
5.
A novel microfluidic droplet generator is proposed, which can control the droplet size through turning an integrated micrometer head with ease, and the size of the produced micro-droplet can be automatically and real-time monitored by an open-sourced software and off-the-shelf hardware. 相似文献
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为了揭示超临界CO2磨料射流流场特性,利用计算流体动力学模拟软件,对超临界CO2磨料射流结构及不同因素对射流流场的影响规律进行了研究。结果表明:超临界CO2磨料射流轴向速度和冲击力随着喷距的增大,先增大后减小,即存在最优喷距,喷射压差为10~30 MPa时最优喷距为3~6倍喷嘴直径;喷射压差一定时,围压由10 MPa增至30 MPa对射流速度场及液相冲击力会造成较小的负面影响。通过超临界CO2射流破岩实验对上述2因素进行了辅助对比验证;流体温度由333 K增至413 K,固液两相轴向速度增大,而流体密度降低,导致液相冲击力减弱;磨料浓度由3.0%连续增至11.0%,射流固液两相轴向速度逐渐降低,降幅逐渐减小。 相似文献
7.
A.A. Toropov A.P. Toropova G. Selvestrel E. Benfenati 《SAR and QSAR in environmental research》2019,30(6):447-455
The Index of Ideality of Correlation (IIC) is a new criterion of the predictive potential for quantitative structure–property/activity relationships. The value of the IIC is a mathematical function sensitive to the value of the correlation coefficient and dispersion (expressed via mean absolute error). The IIC has been applied to develop QSAR models for skin sensitization achieving good predictive potential. The ‘ideal correlation’ is based on elementary fragments of simplified molecular input-line entry system (SMILES) and on the taking into account of the total numbers of nitrogen, oxygen, sulphur and phosphorus in the molecule. 相似文献
8.
Ronald Hesse Carsten Bundesmann Reinhard Denecke 《Surface and interface analysis : SIA》2019,51(13):1342-1350
The improvement of the software UNIFIT 2020 from an analysis processing software for photoelectron spectroscopy (XPS) only to a powerful tool for XPS, Auger electron spectroscopy (AES), X-ray absorption spectroscopy (XAS), and Raman spectroscopy requires new additional programme routines. Particularly, the implementation of the analysis of Raman spectra needs a well-working automatic spike correction. The application of the modified discrete Laplace operator method allows for a perfect localization and correction of the spikes and finally a successful peak fit of the spectra. The theoretical basis is described. Test spectra allow for the evaluation of the presented method. A comparison of the original and spike-corrected real measurements demonstrates the high quality of the method used. 相似文献
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The modular software MOLSIM for all‐atom molecular and coarse‐grained simulations is presented with focus on the underlying concepts used. The software possesses four unique features: (1) it is an integrated software for molecular dynamic, Monte Carlo, and Brownian dynamics simulations; (2) simulated objects are constructed in a hierarchical fashion representing atoms, rigid molecules and colloids, flexible chains, hierarchical polymers, and cross‐linked networks; (3) long‐range interactions involving charges, dipoles and/or anisotropic dipole polarizabilities are handled either with the standard Ewald sum, the smooth particle mesh Ewald sum, or the reaction‐field technique; (4) statistical uncertainties are provided for all calculated observables. In addition, MOLSIM supports various statistical ensembles, and several types of simulation cells and boundary conditions are available. Intermolecular interactions comprise tabulated pairwise potentials for speed and uniformity and many‐body interactions involve anisotropic polarizabilities. Intramolecular interactions include bond, angle, and crosslink potentials. A very large set of analyses of static and dynamic properties is provided. The capability of MOLSIM can be extended by user‐providing routines controlling, for example, start conditions, intermolecular potentials, and analyses. An extensive set of case studies in the field of soft matter is presented covering colloids, polymers, and crosslinked networks. © 2015 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. 相似文献