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1.
The congruence lattices of all algebras defined on a fixed finite set A ordered by inclusion form a finite atomistic lattice \(\mathcal {E}\). We describe the atoms and coatoms. Each meet-irreducible element of \(\mathcal {E}\) being determined by a single unary mapping on A, we characterize completely those which are determined by a permutation or by an acyclic mapping on the set A. Using these characterisations we deduce several properties of the lattice \(\mathcal {E}\); in particular, we prove that \(\mathcal {E}\) is tolerance-simple whenever \(|A|\ge 4\). 相似文献
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Reinhard Oertel Norman Arenz Sten Gunnar Zeitz Jörg Pietsch 《Biomedical chromatography : BMC》2015,29(8):1290-1296
With screening methods in the legal medicine drugs were often detected in autopsy material. In this study the antiarrhythmic and the local anesthetic drug lidocaine could be proved in fifty‐one cases and determined in different autopsy materials. For the first time the comparison of so many distribution patterns of lidocaine in human compartments was possible. A liquid‐liquid extraction procedure, a standard addition method and LC/MS/MS were used for analytics. The measured concentrations in blood were in the therapeutic range or lower. The time between lidocaine application and death was given in twenty‐nine cases. These data were very helpful to estimate and interpret the distribution process of lidocaine between application and death. This time exerted a crucial influence on the distribution of lidocaine in the compartments. Most of the intravenous applicated lidocaine was found in heart blood after a very short time of distribution. Afterwards the highest concentrations were measured in brain. Later the highest concentration was found in the kidney samples or in urine. If the time between lidocaine application and death is known, the results of this study can be used to deepen the knowledge of its pharmacokinetics. If this time is unknown, the circumstances and the causes of death can be better explained. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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The minor relation of functions is generalized to multisorted functions. Pippenger’s Galois theory for minor-closed sets of functions is extended to multisorted functions and multisorted relation pairs. Reflections of minor-closed sets are again minor-closed, and the effect of reflections on the invariant relation pairs of minor-closed sets of multisorted functions is described. 相似文献
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Marcus Richter Sebastian Hahn Dr. Evgenia Dmitrieva Dr. Frank Rominger Dr. Alexey Popov Prof. Dr. Uwe H. F. Bunz Prof. Dr. Xinliang Feng Dr. Reinhard Berger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(5):1345-1352
Polycyclic aromatic azomethine ylides (PAMYs) are powerful building blocks in the bottom-up synthesis of internally nitrogen-containing polycyclic aromatic hydrocarbons (N-PAHs) through 1,3-cycloaddition reactions. In this work, the cycloaddition reaction of PAMYs to asymmetric ortho-quinones is presented, which, in contrast to the addition to symmetric para-quinones, facilitates subsequent condensation reactions and allows the synthesis of three helical N-PAHs with ullazine-quinoxaline ( UQ - 1 – 3 ) backbones. UQ - 1 and UQ - 2 possess two helical centers; however, single-crystal X-ray analysis together with the computational modeling of UQ - 3 elucidate the formation of only the thermodynamically most stable geometry with four helical centers in a (P,P,M,M) configuration. For the series UQ - 1 – 3 , the number of redox steps is directly correlated with the number of ullazine or quinoxaline units incorporated into the targeted molecular backbones. A detailed investigation of the spectroscopic and magnetic properties of the radical cation and anion as well as the dication and dianion species by in situ EPR/UV/Vis-NIR spectroelectrochemistry is provided. The excellent optical and redox properties combined with helical geometries render them possibly applicable as chiral emitter or ambipolar charge transport material in organic electronics. 相似文献
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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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Nolte Steffen Fink Reinhard Krooss Bernhard M. Amann-Hildenbrand Alexandra Wang Yue Wang Moran Schmatz Joyce Klaver Jop Littke Ralf 《Transport in Porous Media》2021,137(3):519-553
Transport in Porous Media - To improve the understanding of gas transport processes in tight rocks (e.g., shales), systematic flow tests with different gases were conducted on artificial micro- to... 相似文献
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Dendritic Glycopolymer as Drug Delivery System for Proteasome Inhibitor Bortezomib in a Calcium Phosphate Bone Cement: First Steps Toward a Local Therapy of Osteolytic Bone Lesions 下载免费PDF全文