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91.
Gowrisankar Reddipalli Mallam Venkataiah Mithilesh Kumar Mishra Nitin W. Fadnavis 《Tetrahedron: Asymmetry》2009,20(15):1802-1805
2-epi-Jaspine B has been synthesized starting from (−)-diethyl tartrate in 12 simple steps and 26.6% overall yield. The key intermediate was obtained via stereoselective base-catalyzed intramolecular oxy-Michael conjugate addition followed by tandem hydrogenation/hydrogenolysis. 相似文献
92.
Nitin Chattopadhyay 《Tetrahedron letters》2005,46(17):3089-3092
Hexakis(2-naphthyloxy)cyclotriphosphazene showed an interesting emission behavior between its monomer and excimer forms, the latter nearly completely dominating in water. Encapsulation studies with β-cyclodextrin in water partially revived the monomer emission. 相似文献
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Robustness Screen in Enantioselective Catalysis Enabled Generation of Enantioenriched Heterocyclic Scaffolds in One Pot 下载免费PDF全文
Pradip N. Bagle Valmik S. Shinde Nitin T. Patil 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3580-3584
Enantioselective catalysis has emerged as a powerful synthetic paradigm and has accelerated the development of new methods to make diverse chiral molecules. Generally, these reactions are very sensitive to the steric and electronic environment present in the catalyst as well as the substrates. With this scenario, the presence of an additional component in the reaction mixture is expected to add complexity in achieving the enantioselective variants. Herein, we report that various enantioenriched molecules could be obtained from multiple starting materials in one pot. The reaction of aminoaromatics A with alkynols B1, B2, B3…?Bn with a AuI/chiral Brønsted acid catalyst afforded AB1*, AB2*, AB3*…ABn*; while, the reaction of alkynols B with aminoaromatics A1, A2, A3…An under the same reaction conditions gave A1B*, A2B*, A3B*…AnB * . 相似文献
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The M.E.S.S. software suite for solving large scale matrix equations and related problems is the successor of the obsolete LyaPack MATLAB® toolbox. The software suite consists of a new MATLAB toolbox and a separate C library C-M.E.S.S. which works independent from MATLAB. Due to the fact that many scientists use Python with NumPy and SciPy for their computations, we want to provide the key algorithms of M.E.S.S. there as well. In this paper, we describe and compare two possible approaches for the implementation, with special focus on their multicore performance. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
98.
Sivacharan Kollipara Girish Bende Nitin Agarwal Brijesh Varshney Jyoti Paliwal 《Chromatographia》2011,73(3-4):201-217
US FDA released guidelines for bioanalytical method validation in 2001 and it became the basis for guidelines such as ANVISA and EMA. Even though there is a general agreement between these guidelines in terms of evaluation of validation parameters, significant diversity exists with respect to methodology employed. Present review compares and summarizes the regulatory guidelines issued by US FDA, ANVISA and EMA for bioanalytical method validation. This review also discusses evaluation of certain validation parameters such as matrix effect, incurred sample reanalysis, various stability aspects, effect of anticoagulant counter ions, specificity in the presence of concomitant medications, and identification of pharmacokinetic repeats wherein specific guidance and general consensus amongst scientific community does not exist. 相似文献
99.
H. P. S. Chauhan Nitin Carpenter Sumit Bhatiya Sapana Joshi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1116-1125
AbstractSeven complexes of type [(C4H9i-O)2PS2]2SbR have been synthesized by the reaction of chlorobis(diisobutyldithiophosphato)antimony(III) with mixed thio and/or oxo donor ligands in 1:1?M stoichiometry, where R?=?SC6H5, OOCC6H5, SCH2COOH, SOCCH3, OOCCH3, SC6H4COOH and OOC(OH)C6H4. These newly synthesized derivatives have been characterized by different physicochemical (elemental analysis (C, H, S, Sb), melting point, molecular weight determination), spectral (UV, IR, NMR (1H, 13C and 31P)) studies, as well as ESI mass, thermal, powder XRD and biological studies. In the final step of weight loss in thermogravimetric analysis, occurring in the range of 245–505?°C, the degradation of the C6H3CO moieties takes place and antimony sulfide (1/2?Sb2S3) is obtained as remaining material, which is useful in various aspects. Bonded to antimony the diisobutyldithiophosphato substituent behaves as an anisobidentate ligand, which is confirmed through spectral analysis. Powder XRD studies indicate that these compounds crystallize in a monoclinic crystal system with an unit cell volume of ~7074–7162 Å3 forming nano ranged (9.69–15.69?nm) crystallites. From the antimicrobial screening tests, bis(diisobutyldithiophosphato)antimony(III) thioglycolate (compound 3) has shown a maximum zone of inhibition (19?mm) against E. coli at 200?μg mL?1 concentration. 相似文献
100.
Non-steroidal anti-inflammatory drugs act by inhibiting cyclooxigenase enzyme in the plasma membrane predominantly. Nowadays many researchers have observed a great involvement of these anti-inflammatory drugs in the cure of different types of cancers. This review shows the role of cyclooxigenase inhibitors specifically type-2 in cure or prevention of different types of cancers. 相似文献