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1.
Mediterranean Journal of Mathematics - In this paper, we introduce the k-generalized Stockwell transform on $${\mathbb {R}}$$ . We investigate for this transform the main theorems of Harmonic... 相似文献
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Meccanica - The present research focuses on dynamic flow control management using tiny jets with three combinations; the first one located at 90° intervals of the base, the second one located... 相似文献
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Marwa Chaabene Soumaya Agren Abdul‐Rahman Allouche Mohamed Lahcinie Rafik Ben Chabane Mohamed Hassen V. Baouab 《应用有机金属化学》2019,33(11)
The novel compounds (E)‐2‐(((4‐hydroxyphenyl)imino)methyl)phenol, Tetraphenyl (hydroxyl) imidazole and their corresponding Boron difluoride complexes were synthesized and characterized by spectroscopic techniques. Density functional theory calculations at B3LYP‐D3/6–311++G (d, p) level of theory were performed for the geometric parameters. The MEP surface studies were used to understand the behavior of molecules in terms of charge transfer and to determine how these molecules interact. We used the GIAO and the B3LYP‐D3 with a 6–311++ G (d, p) basis set to simulate the (1H‐NMR and 19F‐NMR) and the IR spectra, respectively. The corresponding calculated results are in good agreement with the experimental data. The stability of the molecule arising from hyperconjugation interaction and charge delocalization were analyzed using NBO analysis. FMOs revealed the occurrence of charge transfer within the molecule. The complexation using BF3.Et2O was also found to have remarkable effects on the electrochemical properties of the studied molecules, where (b) and (d) present lower chemical stability, higher reactivity and higher polarizability than (a) and (c), respectively. Moreover, the energy gap of (a) and (c) decreased after complexation using BF3.Et2O, indicating the reliability of the electrochemical evaluation of LUMO and HOMO energy levels. These values are the factors explaining the possible charge transfer interaction within the molecule. The absorption and emission spectra of the model compound were also simulated and compared to experimental observations in the DMF solvent. The results of DFT calculations supported the structural and spectroscopic data and confirmed the structure modification of frontier molecular orbitals for BF2 complexes as well as tunable potentials and energy levels. 相似文献
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Journal of Applied Spectroscopy - With the COVID-19 outbreak, many challenges are posed before the scientific world to curb this pandemic. The diagnostic testing, treatment, and vaccine development... 相似文献
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Hussain Majid Ali Akhtar Ghaffar Abdul Inc Mustafa 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6959-6969
Journal of Thermal Analysis and Calorimetry - This research provides the analysis of an analytical method named Homotopy analysis method which is applied to examine the series solutions/results on... 相似文献
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Zarei-Jelyani Mohammad Babaiee Mohsen Baktashian Shaghayegh Eqra Rahim 《Journal of Solid State Electrochemistry》2019,23(10):2771-2783
Journal of Solid State Electrochemistry - Binders play a significant role in the electrochemical performance of anodes in lithium–ion batteries. In this study, mesocarbon microbead (MCMB)... 相似文献
8.
Muhammad Asif Hanif Ahmed Yahya Al-Maskari Jamal Nasser Al-Sabahi Ibtisam Al-Hdhrami Muhammad Mumtaz Khan Ahlam Al-Azkawi 《Natural product research》2015,29(24):2332-2335
Medicago sativa Linn growing in Omani desert were chemically characterised using flame photometry, inductively coupled plasma, gas chromatography–mass spectrometry and high performance liquid chromatographic (HPLC) analysis. HPLC analyses were performed to determine the phenolics and flavonoids present in M. sativa. The major compounds detected in M. sativa leaves were protchaechenic acid (3.22%), hydroxyl benzoic acid (1.05%), β-Phenyl caffate (0.97%) and kaempherol (0.89%). Pterostilbene, a cholesterol-lowering compound, was detected in M. sativa. 相似文献
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Enantioselective and Regiodivergent Functionalization of N‐Allylcarbamates by Mechanistically Divergent Multicatalysis 下载免费PDF全文
Dr. Edward Richmond Ismat Ullah Khan Dr. Joseph Moran 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12274-12277
A pair of mechanistically divergent multicatalytic reaction sequences has been developed consisting of nickel‐catalyzed isomerization of N‐allylcarbamates and subsequent phosphoric‐acid‐catalyzed enantioselective functionalization of the resulting intermediates. By appropriate selection of reaction partners, in situ generated imines and ene‐carbamates are mechanistically partitioned to yield opposing functionalized products. Formal α‐functionalization to give protected α‐arylamines is achieved upon enantioselective Friedel–Crafts reaction with arene nucleophiles, whereas formal β‐functionalization is achieved upon reaction with diarylimine electrophiles in an enantioselective Povarov‐[4+2] cycloaddition. 相似文献