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排序方式: 共有254条查询结果,搜索用时 390 毫秒
41.
Ramesh Kumar C. Vijayakumar V. Suresh A. Jayalakshmi S. Sivaraman N. 《Journal of Radioanalytical and Nuclear Chemistry》2019,321(2):617-627
Journal of Radioanalytical and Nuclear Chemistry - Radiolytic stability of polymeric resins is an important aspects in nuclear materials processing. The different dosage of gamma radiation was... 相似文献
42.
Mohapatra Satyabrata Manglani Nishant Krishnan Dilmel Arumugam Ilavarasu Vijayakumar Madhavan Babu Uddagiri V. 《平面色谱法杂志一现代薄层色谱法》2014,27(4):251-254
JPC – Journal of Planar Chromatography – Modern TLC - Arnebia nobilis has gained an increasing popularity for the recently recognized various pharmacological activities. The root part... 相似文献
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44.
The Remarkable Effect of Halogen Substitution on the Membrane Transport of Fluorescent Molecules in Living Cells
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Harinarayana Ungati Dr. Vijayakumar Govindaraj Prof. Dr. Govindasamy Mugesh 《Angewandte Chemie (International ed. in English)》2018,57(29):8989-8993
Small‐molecule‐based fluorescent probes have become important tools in biology for sensing and imaging applications. However, the biological applications of many of the fluorescent molecules are hampered by low cellular uptake and high toxicity. In this paper, we show for the first time that the introduction of halogen atoms enhances the cellular uptake of fluorescent molecules and the nature of halogen atoms plays a crucial role in the plasma membrane transport in mammalian cells. The remarkably higher uptake of iodinated compounds compared to that of their chloro or bromo analogues suggests that the strong halogen bonding ability of iodine atoms may play an important role in the membrane transport. This study provides a novel strategy for the transport of fluorescent molecules across the plasma membrane in living cells. 相似文献
45.
G. Vijayakumar S. N. Karthick A. R. Sathiya Priya S. Ramalingam A. Subramania 《Journal of Solid State Electrochemistry》2008,12(9):1135-1141
New poly (vinylidenefluoride-co-hexafluoro propylene) (PVDF-HFP)/CeO2-based microcomposite porous polymer membranes (MCPPM) and nanocomposite porous polymer membranes (NCPPM) were prepared by
phase inversion technique using N-methyl 2-pyrrolidone (NMP) as a solvent and deionized water as a nonsolvent. Phase inversion occurred on the MCPPM/NCPPM
when it is treated by deionized water (nonsolvent). Microcomposite porous polymer electrolytes (MCPPE) and nanocomposite porous
polymer electrolytes (NCPPE) were obtained from their composite porous polymer membranes when immersed in 1.0 M LiClO4 in a mixture of ethylene carbonate/dimethyl carbonate (EC/DMC) (v/v = 1:1) electrolyte solution. The structure and porous morphology of both composite porous polymer membranes was examined
by scanning electron microscope (SEM) analysis. Thermal behavior of both MCPPM/NCPPM was investigated from DSC analysis. Optimized
filler (8 wt% CeO2) added to the NCPPM increases the porosity (72%) than MCPPM (59%). The results showed that the NCPPE has high electrolyte
solution uptake (150%) and maximum ionic conductivity value of 2.47 × 10−3 S cm−1 at room temperature. The NCPPE (8 wt% CeO2) between the lithium metal electrodes were found to have low interfacial resistance (760 Ω cm2) and wide electrochemical stability up to 4.7 V (vs Li/Li+) investigated by impedance spectra and linear sweep voltammetry (LSV), respectively. A prototype battery, which consists
of NCPPE between the graphite anode and LiCoO2 cathode, proves good cycling performance at a discharge rate of C/2 for Li-ion polymer batteries. 相似文献
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Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o78-o80
(Z)‐3‐(1H‐Indol‐3‐yl)‐2‐(3‐thienyl)acrylonitrile, C15H10N2S, (I), and (Z)‐3‐[1‐(4‐tert‐butylbenzyl)‐1H‐indol‐3‐yl]‐2‐(3‐thienyl)acrylonitrile, C26H24N2S, (II), were prepared by base‐catalyzed reactions of the corresponding indole‐3‐carboxaldehyde with thiophene‐3‐acetonitrile. 1H/13C NMR spectral data and X‐ray crystal structures of compounds (I) and (II) are presented. The olefinic bond connecting the indole and thiophene moieties has Z geometry in both cases, and the molecules crystallize in space groups P21/c and C2/c for (I) and (II), respectively. Slight thienyl ring‐flip disorder (ca 5.6%) was observed and modeled for (I). 相似文献
48.
Ajayaghosh A Vijayakumar C Praveen VK Babu SS Varghese R 《Journal of the American Chemical Society》2006,128(22):7174-7175
Control over supramolecular assemblies of donor and acceptor arrays in nanoscale dimension that facilitate efficient energy transfer resulting in tunable emission is an outstanding challenge. In pursuit of this goal, we have designed a supramolecular donor-acceptor organogel with tunable emission from green to red through controlled energy transfer by simply varying the acceptor concentration. Temperature-dependent UV/vis absorption, XRD, and AFM studies of the coassembly of 1 (donor) and 2 (acceptor) revealed the intercalation of 2 within the self-assembly of 1. Upon excitation of the decane gels of 1 with 0-2 mol % of 2, quenching of the emission of the former at 509 nm with the formation of the monomer emission of the latter at 555 nm is observed. Upon further addition of 2 (2-20 mol %), the emission was continuously red-shifted to 610 nm, which corresponds to the aggregate emission of 2. Consequently, a 98% quenching of the donor emission was observed at 509 nm. Fluorescence microscopic studies provided visual evidence for the color tuning of the FRET emission. Thus efficient trapping of excitons by "isolated" or "aggregated" acceptors through a subtle control of the self-assembly and the photophysical properties of the donor-acceptor building blocks allowed a continuous shifting of the emission color anywhere between green and red (lambdamax, 509-610 nm) in a supramolecular light harvesting system. 相似文献
49.
This study was aimed at evaluating the preventive role of the ethanolic extract of Lagenaria siceraria (Mol) fruit on membrane-bound enzymes, such as sodium potassium-dependent adenosine triphosphatase (Na(+)/K(+) ATPase), calcium-dependent adenosine triphosphatase (Ca(2+) ATPase) and magnesium-dependent adenosine triphosphatase (Mg(2+) ATPase) on isoproterenol (ISO)-induced myocardial infarction (MI) in rats. Male albino Wistar rats were pretreated with the ethanolic extract of L. siceraria (Mol) fruit (125, 250 and 500?mg?kg(-1) body weight) for a period of 30 days. After the treatment period, ISO (85mg?kg(-1) body weight) was subcutaneously injected into rats at 24-h intervals for 2 days. ISO-induced rats showed a significant (p?0.05) decrease in the activity of Na(+)/K(+) ATPase and an increase in the activities of Ca(2+) and Mg(2+) ATPases in the heart tissues. Pre-treatment with the ethanolic extract of L. siceraria (Mol) fruit for a period of 30 days exhibited a significant (p?0.05) effect in ISO-induced rats. Thus, our study shows that the ethanolic extract of L. siceraria (Mol) fruit has membrane-stabilising role in ISO-induced MI in rats. 相似文献
50.
Vijayakumar Sinnathurai John H. Curran Reginald Hammah 《Mechanics Research Communications》2008,35(4):237-245
It is shown that the anomaly associated with the incorrect evaluation of tangential stresses in the displacement discontinuity (DD) method, commonly used to solve crack problems, is related to the order of singularity of the fundamental solutions of linear elasticity. It is established here that a minimum of linear variation of the shear DD distribution is needed to obtain the correct tangential stress jump across a crack. Alternatively, a correction term (‘patch’) that improves tangential stresses is derived. It is also shown that need for higher functionality is a fundamental requirement rather than a convenient artifice for obtaining better accuracy. 相似文献