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排序方式: 共有318条查询结果,搜索用时 46 毫秒
1.
Kavitha Telikepalli Király Tamás Matuschke Jannik Schlotter Ildikó Schmidt-Kraepelin Ulrike 《Mathematical Programming》2022,192(1-2):567-595
Mathematical Programming - Let G be a digraph where every node has preferences over its incoming edges. The preferences of a node extend naturally to preferences over branchings, i.e., directed... 相似文献
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Amit Vijay Sasane Dr. Antony Sekar Kulandai Raj Tzu-Hsuan Chao Dr. Mu-Jeng Chen Dr. Rai-Shung Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16932-16938
Gold-catalyzed oxidations of propargyl alcohols with nitrones by using a P(tBu)2(o-biphenyl)Au+ catalyst, afforded bicyclic annulation products from the Mannich reactions of gold enolates. The same reactions of propargyl amines with nitrones by using the same gold catalyst gave distinct oxoarylation products. Our DFT calculations indicate that oxidation of propargyl alcohols with nitrones by using electron-rich gold catalysts lead only to gold carbenes, which can generate gold enolates or oxoarylation intermediates with enolate species having a barrier smaller than that of oxoarylation species. 相似文献
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N. Chary Mamillapalli Prof. Govindasamy Sekar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(51):18584-18588
Synthesis of enantiomerically enriched α‐hydroxy amides and β‐amino alcohols has been accomplished by enantioselective reduction of α‐keto amides with hydrosilanes. A series of α‐keto amides were reduced in the presence of chiral CuII/(S)‐DTBM‐SEGPHOS catalyst to give the corresponding optically active α‐hydroxy amides with excellent enantioselectivities by using (EtO)3SiH as a reducing agent. Furthermore, a one‐pot complete reduction of both ketone and amide groups of α‐keto amides has been achieved using the same chiral copper catalyst followed by tetra‐n‐butylammonium fluoride (TBAF) catalyst in presence of (EtO)3SiH to afford the corresponding chiral β‐amino alcohol derivatives. 相似文献
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Nonsteroidal Anti‐inflammatory Drug‐based N‐Allylidene Benzohydrazides and 1‐Acyl‐2‐pyrazolines: Their Synthesis as Potential Cytotoxic Agents In Vitro 下载免费PDF全文
Kavitha Kankanala V. Ranga Reddy Yumnam Priyadarshini Devi Lakshmi Narasu Mangamoori D. Rambabu K. Mukkanti Sarbani Pal 《Journal of heterocyclic chemistry》2015,52(1):105-113
A series of 1‐acyl‐2‐pyrazoline derivatives derived from nonsteroidal anti‐inflammatory drugs was designed as potential anticancer agents. Synthesis of these compounds was carried out via the condensation reaction of chalcones and acid hydrazides under heating. The methodology did not require the use of any costly reagents or catalysts, and the acid hydrazide reactants were readily prepared from mefenamic acid or ibuprofen. A variety of 1‐acyl‐2‐pyrazolines was prepared in good to excellent yields. An N‐allylidene benzohydrazide intermediate was isolated during the reaction optimization study, the structure of which was confirmed unambiguously by X‐ray single crystal data. A range of N‐allylidene benzohydrazides were also prepared in good yields. Some of the compounds synthesized showed promising cytotoxic activities when tested against HCT‐15 human colon cancer cell line in vitro. 相似文献
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Synthesis,Characterization, and Antibacterial Activity of Novel (1H‐Benzo[d]imidazole‐2‐yl)‐6‐(diethylamino)‐3H‐one‐xanthene,Phenoxazine, and Oxazine 下载免费PDF全文
Vikas S. Patil Vikas S. Padalkar Kiran R. Phatangare Prashant G. Umape Bhushan N. Borase N. Sekar 《Journal of heterocyclic chemistry》2015,52(1):124-129
A series of novel (1H‐benzo[d]imidazole‐2‐yl)‐6‐(diethylamino)‐3H‐one‐xanthene, phenoxazine, and oxazine derivatives have been synthesized from 2‐(2′,4′‐dihydroxyphenyl) benzimidazole intermediate. Synthesized compounds 8a , 8b , 8c , 8d are fluorescent in solution, photophysical properties of compounds were studied and results revealed that compounds absorb and emit in UV–visible region with good fluorescence quantum yield. Synthesized compounds are thermally stable up to 300°C. The antibacterial activities of the synthesized compounds were studied by the well‐diffusion method. Escherichia coli (ATTC‐25922), Staphylococcus aureus (ATCC‐25923), Micrococcus (ATCC‐4698), and Bacillus subtilis (ATCC‐55422) were used to investigate the antibacterial activities. 相似文献
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Aparna L. Joshi Pratiksha H. Roham Rooth Mhaske Mahadev Jadhav Kavitha Krishnadas Amol Kharat 《Natural product research》2015,29(23):2261-2264
Calotropis procera (family: Asclepiadaceae) contains cardiac glycosides which are cytotoxic to cancer cells. The extracts of C. procera have been reported to be cytotoxic to many cancer cell lines and this is the first report against the human skin melanoma cells (SK-MEL-2). The SK-MEL-2 cells treated with C. procera methanolic extract (CPME) were analysed for growth inhibition and apoptosis. The exposure of phosphatidylserine in apoptotic SK-MEL-2 was analysed by using the Annexin-V FITC flow cytometry method. In CPME-treated SK-MEL-2 cells, 19.6% of apoptotic and 58.3% dead cells were observed. The 15.97% and 15.85% of early apoptotic cells were found at 20 μg/mL of the ouabain and paclitaxel, respectively. Active caspases, nuclear degradation confirmed apoptotic SK-MEL-2 cells in time- and dose-dependent manner. The cell cycle analysis shows that CPME treated cells halt at G2/M phase. Significant cytotoxic activity of CPME against SK-MEL-2 may be attributed to its high cardenolide content. 相似文献
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Vijayakumar Sekar González-Sánchez Zaira I. Malaikozhundan Balasubramanian Saravanakumar Kandasamy Divya Mani Vaseeharan Baskaralingam Durán-Lara Esteban F. Wang Myeong-Hyeon 《Journal of Cluster Science》2021,32(5):1129-1139
Journal of Cluster Science - Metal oxide nanoparticles (NPs) have gained attention in biomedicine due to their broad spectrum of applications, such as targeted drug delivery, their use as... 相似文献
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Journal of Thermal Analysis and Calorimetry - More than a decade, a numerous experimental and theoretical studies of thermophysical properties of nanofluids are conducted to reveal its heat... 相似文献