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71.
Gülgün Yeniehirli Nuren Altunta
zta Ertan ahin Mustafa elebier Nilgün Ancn Selma Gül
zta 《Heteroatom Chemistry》2010,21(6):373-385
A new series of diorganotin complexes of the type R2SnL (L1: N‐(2‐hydroxy‐5‐chlorophenyl)‐ 3‐ethoxysalicylideneimine, R = Me, (Me2SnL1), R = n‐Bu, (n‐Bu2SnL1), R = Ph, (Ph2SnL1), L2: N‐(2‐hydroxy‐4‐nitro‐5‐chlorophenyl)‐3‐ethoxysalicylideneimine, R = Ph, Ph2SnL2, L3: N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐methoxysalicylideneimine, R = Me, (Me2SnL3), R = n‐Bu, (n‐Bu2SnL3), L4: N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐ethoxysalicylideneimine, R = Me, (Me2SnL4), R = n‐Bu, (n‐Bu2SnL4)) were synthesized and characterized by elemental analysis, infrared (IR), 1H, and 13C NMR mass spectroscopic techniques, and electrochemical measurements. Ph2SnL1 and Ph2SnL2 were also characterized by X‐ray diffraction analysis and were found to show a fivefold C2NO2 coordination geometry nearly halfway between a trigonal bipyramidal and distorted square pyramidal arrangement. The C Sn C angles in the complexes were calculated using Lockhart's equations with the 1J(117/119Sn‐13C) and 2J(117/119Sn‐1H) values from the 1H NMR and 13C NMR spectra. Biocidal activity tests against several micro‐organisms and some fungi indicate that all the complexes are mildly active against Gram (+) bacteria and the fungi, A. niger and inactive against Gram (−) bacteria. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:373–385, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20628 相似文献
72.
A brief review of two-body Dirac and Kemmer-Duffin-Petiau approaches for the bound state problem of two fermions is presented from an algebraic point of view in a comparative manner. Reduction of the direct product of two Dirac spaces is discussed.Work supported by the T.B.T.A.K. under TBAG/CG-1. 相似文献
73.
Selma Kreisky 《Monatshefte für Chemie / Chemical Monthly》1959,90(3):417-417
Ohne Zusammenfassung 相似文献
74.
There is a correspondence between functions in the maximal ideal of the local ring of a rational singularity and certain positive
divisors supported on the exceptional fiber of a resolution of the singularity. Here we give an algorithm to obtain a generating
set over ℤ of these divisors. 相似文献
75.
Alisina Bazrafshan Travis A. Meyer Hanquan Su Joshua M. Brockman Aaron T. Blanchard Selma Piranej Yuxin Duan Yonggang Ke Khalid Salaita 《Angewandte Chemie (International ed. in English)》2020,59(24):9514-9521
Inspired by biological motor proteins, that efficiently convert chemical fuel to unidirectional motion, there has been considerable interest in developing synthetic analogues. Among the synthetic motors created thus far, DNA motors that undertake discrete steps on RNA tracks have shown the greatest promise. Nonetheless, DNA nanomotors lack intrinsic directionality, are low speed and take a limited number of steps prior to stalling or dissociation. Herein, we report the first example of a highly tunable DNA origami motor that moves linearly over micron distances at an average speed of 40 nm/min. Importantly, nanomotors move unidirectionally without intervention through an external force field or a patterned track. Because DNA origami enables precise testing of nanoscale structure‐function relationships, we were able to experimentally study the role of motor shape, chassis flexibility, leg distribution, and total number of legs in tuning performance. An anisotropic rigid chassis coupled with a high density of legs maximizes nanomotor speed and endurance. 相似文献
76.
77.
Exposure of acetonitrile/methanol solutions of [PPN][Ru(DPPBT)3] [PPN = bis(triphenylphosphoranylidene); DPPBT = 2-diphenylphosphinobenzene thiolate] to oxygen initiates metal-centered oxidation, yielding the ruthenium(III) thiolate Ru(DPPBT)3. Ru(DPPBT)3 further reacts with oxygen, at sulfur, to give the ruthenium(III) sulfinate complex [Ru(DPPBT-O2)2(DPPBT)], which is reduced under ambient conditions to [PPN][Ru(DPPBT-O2)2(DPPBT)]. Ruthenium(II) sulfinate is the only product isolated from acetonitrile/methanol. Yellow crystals of [PPN][Ru(DPPBT-O2)2(DPPBT)] were obtained. Ruthenium(III) sulfinate was isolated as green prism-shaped crystals upon oxygenation of [PPN][Ru(DPPBT)3] in chlorobenzene/hexane. Electrochemical oxidation of ruthenium(II) sulfinate yields the ruthenium(III) derivative, which is rapidly reduced back to ruthenium(II) upon the addition of hydroxide. 相似文献
78.
Hilmi Namli Ayse Dilek Azaz Sedat Karabulut Selma Çelen Raif Kurtaran Canan Kazak 《Transition Metal Chemistry》2007,32(2):266-270
The cobalt(IV) complex of 2,6-diacetylpyridine dioxime (dapdoH2) was prepared and characterized by X-ray diffraction, elemental analysis and FT-IR. The titled complex was found to crystallize
in the orthorhombic space group and was screened for antibacterial and antifungal activities by the disc diffusion and microtitter
plate techniques using DMF as solvent. It has been found that the antimicrobial activity of the complex [Co(dapdo)2] is slightly higher than the free ligand (dapdoH2). 相似文献
79.
80.
Diego Lomonaco Fabricio Y. Cangane Selma E. Mazzetto 《Journal of Thermal Analysis and Calorimetry》2011,104(3):1177-1183
In this work, poly(methyl methacrylate) films 1% additivated with new thiophosphate esters antioxidants derived from technical
Cashew Nutshell Liquid (CNSL), a byproduct of the cashew nut (Anacardium occidentale L.) industry, were investigated by thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) measurements under
inert (N2) and oxidative (synthetic air) atmospheres. Three new products were synthesized and characterized by GC/MS, 1H and 31P NMR. The analyses were focused on the onset (T
e) and offset temperature (T
o) of degradation of the films, and on the maximum degradation temperature (T
MAX). It was observed that the thermal stability of the films increased with the addition of the thiophosphate ester antioxidants,
which indicates that CNSL could be used as a natural source of phenolic material for the synthesis of antioxidants. 相似文献