全文获取类型
收费全文 | 173篇 |
免费 | 5篇 |
专业分类
化学 | 123篇 |
力学 | 2篇 |
数学 | 35篇 |
物理学 | 18篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 8篇 |
2015年 | 11篇 |
2014年 | 1篇 |
2013年 | 12篇 |
2012年 | 7篇 |
2011年 | 8篇 |
2010年 | 4篇 |
2009年 | 7篇 |
2008年 | 9篇 |
2007年 | 8篇 |
2006年 | 11篇 |
2005年 | 12篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1994年 | 3篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1970年 | 3篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1946年 | 1篇 |
1943年 | 2篇 |
1927年 | 1篇 |
排序方式: 共有178条查询结果,搜索用时 15 毫秒
41.
Dezelah CL El-Kadri OM Szilágyi IM Campbell JM Arstila K Niinistö L Winter CH 《Journal of the American Chemical Society》2006,128(30):9638-9639
The atomic layer deposition of W2O3 films was demonstrated employing W2(NMe2)6 and water as precursors with substrate temperatures between 140 and 240 degrees C. At 180 degrees C, surface saturative growth was achieved with W2(NMe2)6 vapor pulse lengths of >/=2 s. The growth rate was about 1.4 A/cycle at substrate temperatures between 140 and 200 degrees C. Growth rates of 1.60 and 2.10 A/cycle were observed at 220 and 240 degrees C, respectively. In a series of films deposited at 180 degrees C, the film thicknesses varied linearly with the number of deposition cycles. Time-of-flight elastic recoil analyses demonstrated stoichiometric W2O3 films, with carbon, hydrogen, and nitrogen levels between 6.3 and 8.6, 11.9 and 14.2, and 4.6 and 5.0 at. %, respectively, at substrate temperatures of 160, 180, and 200 degrees C. The as-deposited films were amorphous. Atomic force microscopy showed root-mean-square surface roughnesses of 0.7 and 0.9 nm for films deposited at 180 and 200 degrees C, respectively. The resistivity of a film grown at 180 degrees C was 8500 microhm cm. 相似文献
42.
Summary Acylation of 5-amino-1-substituted pyrazoles gave — depending on the substituents in position 3 and agents used — mono-, di- and triacylated products, respectively.Poster presented at the 10th International Congress on Heterocyclic Chemistry, Waterloo/Canada, August 11–16, 1985. 相似文献
43.
Kéki S Szilágyi LS Deák G Zsuga M 《Rapid communications in mass spectrometry : RCM》2003,17(8):783-787
A detailed investigation of the most commonly used plasticizers, such as phthalate, adipate and trimellitate esters, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and post-source decay (PSD) MALDI-TOFMS/MS is described. It is shown that PSD MALDI-TOFMS/MS is capable of unambiguous determination of the different types of plasticizers. The determination of the types of plasticizers from different PVC samples by PSD MALDI-TOFMS/MS, without the need for solvent extraction, is also demonstrated. The fragmentation mechanisms of these plasticizers cationized with protons and sodium ions are also reported. 相似文献
44.
K. Kovács A. A. Kamnev E. Kuzmann Z. Homonnay P. Á. Szilágyi V. K. Sharma A. Vértes 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(3):513-517
Summary This paper describes the M?ssbauer investigations of iron(III) salts in aqueous solutions in the presence of indole-3-alkanoic
acid ligands. The measurements showed two parallel reactions between the ligands and ferric ions: a complex formation and
a redox process. The oxidation process takes place in the ligands, and a part of Fe3+is reduced to Fe2+. 相似文献
45.
P. Szilágyi 《Acta Mathematica Hungarica》1998,81(1-2):125-139
Different types of linear inequality systems have different consequence inequalities. Investigating several types of linear inequality systems, the present paper gives explicitly those consequences of the given system of linear inequalities that are all consistent if and only if the original system is consistent. Our results generalize the well-known Kuhn-Fourier theorem, and present important particular cases. 相似文献
46.
Madalina Barbaiani Cristina Bibire Jürgen Dassow Aidan Delaney Szilárd Fazekas Mihai Ionescu Guangwu Liu Atif Lodhi Benedek Nagy 《Journal of Applied Mathematics and Computing》2006,22(1-2):21-38
Programmed grammars, one of the most important and well investigated classes of grammars with context-free rules and a mechanism controlling the application of the rules, can be described by graphs. We investigate whether or not the restriction to special classes of graphs restricts the generative power of programmed grammars with erasing rules and without appearance checking, too. We obtain that Eulerian, Hamiltonian, planar and bipartite graphs and regular graphs of degree at least three are pr-universal in that sense that any language which can be generated by programmed grammars (with erasing rules and without appearance checking) can be obtained by programmed grammars where the underlying graph belongs to the given special class of graphs, whereas complete graphs, regular graphs of degree 2 and backbone graphs lead to proper subfamilies of the family of programmed languages. 相似文献
47.
Kalász H Szücs Z Tihanyi M Szilágyi A Lengyel J 《Journal of chromatography. A》2005,1079(1-2):208-212
Nepsilon-Monomethyllysine was identified in the serum, urine, brain, and liver samples of rats treated per os with L-deprenyl. The identification procedure included reaction with Fmoc chloride, clean-up, and analysis using HPLC-UV-MS. Oral administration of (-)-N-14C-methyl-N-propynyl(2-phenyl-1-methyl)ethylammonium hydrochloride L-deprenyl) to rats resulted in transfer of the radiolabelled methyl group to the Nepsilon-amino group of the endogenous lysine. The radiolabelled Nepsilon-monomethyllysine was urinary eliminated together with the other radiolabelled deprenyl metabolites, such as deprenyl-N-oxide and methamphetamine. The presence of Nepsilon-monomethyllysine has also been traced, and its concentrations were compared in the serum, liver and brain of rats subjected to L-deprenyl treatment. Methyl group transfer from the L-deprenyl to endogenous compounds; and the urinary elimination of their products may offer a vital way to eliminate or to decrease the degree of drug transmethylation to the lysine constituents of blood vessels' proteins. 相似文献
48.
49.
50.
Fluorescence of a Histidine-Modified Enhanced Green Fluorescent Protein (EGFP) Effectively Quenched by Copper(II) Ions 总被引:1,自引:0,他引:1
Emese-Éva Bálint Judit Petres Mária Szabó Csongor-Kálmán Orbán László Szilágyi Beáta Ábrahám 《Journal of fluorescence》2013,23(2):273-281
Two histidines were introduced by site-directed mutagenesis into the structure of Enhanced Green Fluorescent Protein, replacing the serine at position 202 and the glutamine at position 204 for increasing the sensitivity of the protein towards different metal ions by creating possible metal binding sites near the chromophore group. There is no appreciable difference between the absorbance and fluorescence spectra of the two proteins (wild type and the double-histidine mutant) indicating that the mutation does not change the environment of the fluorophore. Fluorescence quenching was measured at different pH (6.5–8) and temperatures (20–45 °C) varying the concentration of metal ions. Under optimal conditions (pH?=?7.5, 20 °C) the mutant’s Kd is 16 nM, it binds copper more than 200fold stronger than the wild type EGFP. 相似文献