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排序方式: 共有333条查询结果,搜索用时 140 毫秒
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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
94.
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
95.
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
96.
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
97.
Device calibration impacts security of quantum key distribution 总被引:1,自引:0,他引:1
Jain N Wittmann C Lydersen L Wiechers C Elser D Marquardt C Makarov V Leuchs G 《Physical review letters》2011,107(11):110501
Characterizing the physical channel and calibrating the cryptosystem hardware are prerequisites for establishing a quantum channel for quantum key distribution (QKD). Moreover, an inappropriately implemented calibration routine can open a fatal security loophole. We propose and experimentally demonstrate a method to induce a large temporal detector efficiency mismatch in a commercial QKD system by deceiving a channel length calibration routine. We then devise an optimal and realistic strategy using faked states to break the security of the cryptosystem. A fix for this loophole is also suggested. 相似文献
98.
Chetan C. Chintawar Amit K. Yadav Nitin T. Patil 《Angewandte Chemie (International ed. in English)》2020,59(29):11808-11813
Herein, we disclose the gold‐catalyzed 1,2‐diarylation of alkenes through the interplay of ligand‐enabled AuI/AuIII catalysis with the idiosyncratic π‐activation mode of gold complexes. Unlike the classical migratory‐insertion‐based approach to 1,2‐diarylation, the present approach not only circumvents the formation of direct Ar?Ar′ coupling and Heck‐type side products but more intriguingly demonstrates reactivity and selectivity complementary to those of previously known metal catalysis (Pd, Ni, or Cu). Detailed investigations to underpin the mechanistic scenario revealed oxidative addition of aryl iodides to an AuI complex to be the rate‐limiting step owing to the non‐innocent nature of the aryl alkene. 相似文献
99.
Manisha Sharma Arti Maheshwari Nitin Bindal 《Journal of heterocyclic chemistry》2013,50(Z1):E116-E120
Some new derivatives of 3‐chloro‐1‐(4a,10b‐diazaphenanthrene‐2‐yl)‐4‐phenyl azetidin‐2‐one were synthesized through the reaction of N‐{4‐[phenyldiazenyl] phenyl}‐N‐[phenyl methylene] amine with 4‐[phenyldiazenyl] aniline. The resulting 3‐chloro‐4‐phenyl‐1‐{4‐[phenyldiazenyl] phenyl} azetidin‐2‐one intermediate in benzene was irradiated in a Pyrex vessel with 350 nm UV light in a photochemical reactor to give the desired derivatives (4a–j) . Structures of the new compounds were verified on the basis of spectral and elemental methods of analyses. Nine of the prepared compounds were tested for their anti‐inflammatory effects; most of these compounds showed potent and significant results compared with indomethacin. 相似文献
100.
Nitin D. Gaikwad Sachin V. Patil Vivek D. Bobade 《Journal of heterocyclic chemistry》2013,50(3):519-527
A series of new 1‐[4‐(2,3,4‐substituted‐phenyl) thiazol‐2‐yl]‐3‐(2,3,4‐substituted‐phenyl)‐1H‐pyrazole‐4‐carbaldehyde ( 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k , 4l , 4m ), 4‐[4‐(4‐substituted‐phenyl) thiazol‐2‐yl]‐3‐(4‐substituted‐phenyl)‐1‐phenyl‐1H‐pyrazole ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i ), 4‐[4‐(4‐substituted phenyl)thiazol‐2‐yl]‐1‐phenyl‐1H‐pyrazol‐3‐amine ( 10a , 10b , 10c , 10d , 10e , 10f , 10g ) have been synthesized by using Vilsmeier Haack formylation and Hantzsch reaction in high yield. All the synthesized compounds were tested qualitative (Zone of inhibition) and quantitative antimicrobial activities (MIC). Most of the synthesized compounds showed potent antimicrobial activity against gram positive and gram negative bacteria as well as fungi species. 相似文献