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1.
Mustafa Çelebier Ertan Şahin Nilgün Ancın Nurşen Altuntaş Öztaş Selma Gül Öztaş 《应用有机金属化学》2007,21(10):viii-viii
The article referenced above was first published online on 30 August 2007 with incorrect pagination; the pagination has now been corrected online and in print. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
2.
Diego Lomonaco Francisco Jonas Nogueira Maia Selma Elaine Mazzetto 《Journal of Thermal Analysis and Calorimetry》2013,111(1):619-626
In this study, the thermal-oxidative stability of poly(methyl methacrylate), PMMA, 1 % additivated with replenishable phenolic lipids is evaluated by thermogravimetric (TG/DTG) analyses and differential scanning calorimetry (DSC) analyses. Since technical cashew nutshell liquid (CNSL), a byproduct from the cashew industry, is composed basically of two phenolic lipids, cardanol and cardol, the utilization of this industrial waste and its main components as a new source of bioadditives for use as antioxidants is evaluated. The TG analyses revealed that addition of the phenolic constituent of CNSL increased the thermal stability of PMMA films considerably. The results obtained were also confirmed by DSC analyses. 相似文献
3.
Selma Bal Sedat Salih Bal Abdullah Erener Hatice Nur Halipci Seyhan Akar 《Chemical Papers》2014,68(3):352-361
Four water soluble azo dyes, 4-(isopropyl)-2-[(E)-(4-chlorophenyl)diazenyl]phenol (L 1), 4-(isopropyl)-2-[(E)-(2,4-dichlorophenyl)diazenyl]phenol (L2), 4-(sec-butyl)-2-[(E)-(4-chlorophenyl) diazenyl]phenol (L 3), 4-(sec-butyl)-2-[(E)-(2,4-dichlorophenyl)diazenyl]phenol (L 4), and their Cu(II) and Ni(II) complexes were synthesized and characterized using spectroscopic methods. Examination of their thermal stability revealed similar decomposition temperature of approximately 260–300°C and that they were more thermally stable than their metal complexes. Ni(II) complexes of ligands L2 and L4 were more stable than the other coordination compounds. Among the synthesized ligands, L2 and the complexes Cu(L3)2 and Ni(L4)2 showed both antimicrobial and antifungal activity. However, the other ligands and the complexes were poorly active against selected microorganisms. 相似文献
4.
Maria A. S. Rios Francisco F. P. Santos Francisco J. N. Maia Selma E. Mazzetto 《Journal of Thermal Analysis and Calorimetry》2013,112(2):921-927
This work shows the evaluation of three antioxidants (2,6-di-t-butyl-4-methylphenol (BHT)—synthetic antioxidant, hydrogenated cardanol (HC), and alkyl hydrogenated cardanol (AHC)—both derived from cashew nut shell liquid) on the thermo-oxidative stability of the soybean biodiesel. The antioxidants were added at concentrations of 200, 300, and 400 ppm, and the oxidative stability of the biofuel with and without antioxidants were investigated by thermogravimetric analysis (TG-DTG and IPDT) and Metrohm 743 Rancimat per the EN 14112 method. The results showed that all antioxidants contributed for the thermo-oxidative stability of the soybean biodiesel as follows: soybean biodiesel < soybean biodiesel + BHT < soybean biodiesel + HC < soybean biodiesel + AHC. In the Rancimat method, the results showed that the antioxidants influenced the biodiesel stability with an increase of at least 71 %. 相似文献
5.
Selma Belen Erik Kropat Gerhard-Wilhelm Weber 《Central European Journal of Operations Research》2011,19(1):1-17
In this paper, the Maki–Thompson model is slightly refined in continuous time, and a new general solution is obtained for
each dynamics of spreading of a rumour. It is derived an equation for the size of a stochastic rumour process in terms of
transitions. We give new lower and upper bounds for the proportion of total ignorants who never learned a rumour and the proportion
of total stiflers who either forget the rumour or cease to spread the rumour when the rumour process stops, under general
initial conditions. Simulation results are presented for the analytical solutions. The model and these numerical results are
capable to explain the behaviour of the dynamics of any other dynamical system having interactions similar to the ones in
the stochastic rumour process and requiring numerical interpretations to understand the real phenomena better. The numerical
process in the differential equations of the model is investigated by using error-estimates. The estimated error is calculated
by the Runge–Kutta method and found either negligible or zero for a relatively small size of the population. This pioneering
paper introduces a new mathematical method into Operations research, motivated by various areas of scientific, social and
daily life, it presents numerical computations, discusses structural frontiers and invites the interested readers to future
research. 相似文献
6.
Metin Başarır Selma Altundağ Mustafa Kayıkçı 《Rendiconti del Circolo Matematico di Palermo》2010,59(2):277-287
The purpose of the paper is to introduce the concepts of almost λ-statistical convergence and strongly almost λ-convergence of sequences of fuzzy numbers. We establish some connections between these concepts. It is also shown that if
a sequence of fuzzy numbers is strongly almost λ-convergent with respect to a sequence of Orlicz funtions then it is almost λ-statistical convergent. 相似文献
7.
A direct kinetic study is reported for the electrophilic amination of substituted phenylmagnesium bromides with N,N‐dimethyl O‐(mesitylenesulfonyl)hydroxylamine in THF. Rate data, Hammett relationship, and activation entropy are consistent with a SN2 displacement involving the attack of carbanions to sp3N in the amination reagent (AR). Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
8.
Aryl Grignard reagents react with N,N‐dimethyl O‐(mesitylenesulfonyl)hydroxylamine in THF under Barbier conditions at room temperature and give N,N‐dimethylanilines with high yields in a 2‐h reaction. The amination yield of in situ Grignard reagents were not lower than those of preformed aryl Grignard reagents. In situ cycloalkyl‐, allyl‐, and benzylmagnesium bromides did not react with N,N‐dimethyl O‐(mesitylenesulfonyl)hydroxylamine, except that amination of in situ n‐hexylmagnesium bromide resulted in a medium yield. Grignard–Barbier‐type amination of aryl bromides with N,N‐dimethyl O‐(mesitylenesulfonyl)hydroxylamine provides a new alternative route for the synthesis of N,N‐dimethylanilines. 相似文献
9.
A. Dilek Azaz Selma Celen Hilmi Namli Onur Turhan Raif Kurtaran Canan Kazak N. Burcu Arslan 《Transition Metal Chemistry》2007,32(7):884-888
A complex of NiII with 2,6-diacetylpyridinedihydrazone (L) towards nickel(II) has been prepared and characterized by means of elemental analyses,
IR, electronic spectra and single crystal X-ray analyses. [NiL2](NO3) was crystallized in the tetragonal space group P-4 21 c. The complex exhibits the expected coordination sphere with six
nitrogen atoms coordinated to the central NiII with a deformation from pseudo-octahedral geometry. Antimicrobial activities of the ligand and its complex were investigated. 相似文献
10.
Zafer Kandemir Selma Mayda Nejat Bulut 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(5):113
We study the electronic structure and correlations of vitamin B12 (cyanocobalamine) by using theframework of the multi-orbital single-impurity Haldane-Anderson model of atransition-metal impurity in a semiconductor host. The parameters of the effectiveHaldane-Anderson model are obtained within the Hartree-Fock (HF) approximation. Thequantum Monte Carlo (QMC) technique is then used to calculate the one-electron andmagnetic correlation functions of this effective model. We observe that new states forminside the semiconductor gap found by HF due to the intra-orbital Coulomb interaction atthe impurity 3d orbitals. In particular, the lowest unoccupiedstates correspond to an impurity bound state, which consists of states from mainly the CNaxial ligand and the corrin ring as well as the Co eg-like orbitals. We alsoobserve that the Co?(3d) orbitals can develop antiferromagneticcorrelations with the surrounding atoms depending on the filling of the impurity boundstates. In addition, we make comparisons of the HF+QMC data with the density functionaltheory calculations. We also discuss the photoabsorption spectrum of cyanocobalamine. 相似文献