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排序方式: 共有254条查询结果,搜索用时 156 毫秒
1.
Molecular Structure,Vibrational Spectra,Molecular Docking,and ADMET Study of Cellulose Triacetate II
Celik Sefa Demirag A. Demet Ozel Aysen E. Akyuz Sevim 《Optics and Spectroscopy》2020,128(8):1138-1150
Optics and Spectroscopy - People have started to look for alternative sources because of the health problems created by petrochemical products used in all areas of human life and environmental... 相似文献
2.
Lakhera Shradha Rana Meenakshi Devlal Kamal Celik Ismail Yadav Rohitash 《Structural chemistry》2022,33(3):703-719
Structural Chemistry - Tridax procumbens is a flowering plant of the Asteraceae family with a wide range of medicinal uses like anti-inflammatory, anti-diabetic, anti-microbial, immunomodulatory,... 相似文献
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Prof. Dr. Holger Braunschweig Charlotte Brückner Dr. Mehmet Ali Celik Dr. Klaus Dück Dr. Florian Hupp Dr. Thomas Kramer Johannes Krebs Dr. Ivo Krummenacher 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(31):11056-11064
Taking advantage of an improved synthesis of [Ti(η6‐C6H6)2], we report here the first examples of ansa‐bridged bis(benzene) titanium complexes. Deprotonation of [Ti(η6‐C6H6)2] with nBuLi in the presence of N,N,N′,N′′,N′′‐pentamethyldiethylenetriamine (pmdta) leads to the corresponding 1,1′‐dilithio salt [Ti(η6‐C6H5Li)2] ? pmdta that enables the preparation of the first one‐ and two‐atom‐bridged complexes by simple salt metathesis. The ansa complexes were fully characterized (NMR spectroscopy, UV/Vis spectroscopy, elemental analysis, and X‐ray crystallography) and further studied electrochemically and computationally. Moreover, [Ti(η6‐C6H6)2] is found to react with the Lewis base 1,3‐dimethylimidazole‐2‐ylidene (IMe) to give the bent sandwich complex [Ti(η6‐C6H6)2(IMe)]. 相似文献
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Holger Braunschweig Mehmet Ali Celik Rian D. Dewhurst Magdalena Heid Florian Hupp Sakya S. Sen 《Chemical science》2015,6(1):425-435
Synthetic access to low-coordinate Pb mono- and dications is in general impeded due to their poor solubility and highly electrophilic nature. However, the electrophilicity of these cations can be tamed by attaching them to electron-rich transition metals. Following this principle we have isolated low-valent Pb mono- ([(Cy3P)2Pt–PbCl]2[AlCl4]2, 8a) and dications ([(Cy3P)2Pt(Pb)][AlCl4]2, 11) in the coordination sphere of platinum. The same approach then has been implemented for the isolation of analogous low-valent Sn mono- (7a) and dications (10). An energy decomposition analysis (EDA-NOCV) was performed to investigate the nature of Pt–Pb and Pb–Cl bonding in [(Cy3P)2Pt(PbCl2)] (2), 8a and 11. The results show that the Pt–Pb bonds in 8a and 11 are electron-sharing in nature, whereas that of the precursor 2 is a dative bond. The breakdown of attractive interactions in 2, 8a and 11 reveals that the ionic interactions in the analyzed Pt–Pb and Pb–Cl bonds are always stronger than the covalent interactions, except for the Pb–Cl bond in 8a. The calculated D3 dispersion energies show that dispersion interactions play a key role in the thermodynamic stability of 2, 8a and 11. 相似文献
6.
In situ PM‐IRRAS studies of organothiols and organosilane monolayers–ZnO interfaces at high water activities 下载免费PDF全文
Boray Torun Ignacio Giner Guido Grundmeier Ozlem Ozcan 《Surface and interface analysis : SIA》2017,49(1):71-74
In situ photoelastic‐modulated Fourier transform infrared reflection absorption spectroscopy has been applied for the investigation of interfacial stability of organothiol and organosilane monolayer films on nanocrystalline zinc oxide thin films. It has been shown that for octadecyltriethoxysilane films, exposure to high water activities results in physisorption of water in the cross‐linked film. This high water activity at the interface leads to a reversible wet de‐adhesion of the interfacial silanol groups from the ZnO surface. However, the organothiol seems to form a denser monolayer and a stable by S–Zn bond that is resistant to the competition with adsorbed water. The reversible attachment for cross‐linked organosilanol films has been demonstrated for the first time by means of an in situ spectroscopic method on model ZnO surfaces. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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The B,N-bifunctional catalyst homoboroproline has been applied to a catalytic asymmetric nitroalkene-Michael addition to β-nitrostyrene analogues, showing broad substrate tolerance, high conversions and moderate to good asymmetric induction. The ability of homoboroproline to act as an efficient catalyst based on enamine-formation of the secondary amine, coupled with intramolecular Lewis-acid chelation of the nitro function, in a non-FLP manner, to effect efficient and enantioselective catalysis via a proposed large 10-membered ring transition state is remarkable and reinforced by theoretical calculations. 相似文献
8.
Nevin Celik 《Heat and Mass Transfer》2011,47(10):1209-1217
Current work presents the comparison of the cooling characteristics of roughened and smooth heated surfaces subjected to co-axial impinging jet. The work fluid is air and the data runs are performed for jet Reynolds numbers for 10,000, 20,000 and 40,000, and non-dimensional surface to jet exit spacing, H/D, from 1 to 10. The co-axial jet configuration is based on a fully developed pipe flow encountering a double-pipe arrangement and splitting between the two pipes. The inner to outer diameter ratio is 0.5. A straight pipe without inner section is used as the circular jet. The impingement of circular jets to the roughened and smooth surfaces is also performed for comparison. Average Nusslet numbers were obtained to show the heat transfer enhancement from the surface. A good agreement between the literature and present paper was obtained. As a result, average Nusselt number with co-axial jet impingement to the roughened surface increased by up to 27% comparing to the circular jet impingement. In addition, the average Nusselt number increased with roughened surface by up to 6% over the whole surface area, comparing to the smooth surface. 相似文献
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Keziban Usta Ozlem Ozen Karakus Ayhan Usta Hasalettin Deligoz 《Magnetic resonance in chemistry : MRC》2013,51(10):671-675
A macrocyclic azocalix[4]arene (1) based ester derivative was synthesized. The single crystals of azocalix[4]arene were produced by slow evaporation of concentrated ethyl acetate solutions. These single crystals were exposed to 60Co gamma rays with a dose rate of 0.980 kGy h‐1 for 48 and 72 h to produce a stable free radical. Electron paramagnetic resonance (EPR) measurements were performed in three mutually perpendicular planes of the single crystal in the magnetic field, in addition, temperature dependence of the EPR signal was studied between 120 K and 450 K. The spectra were found to be temperature and angular dependent. Analysis based on the spectra recorded showed that a free radical was formed by fission of a C–H bond. This radical is described as ?CaHCbH3 The averages of the principal values of the hyperfine parameters and g‐factor are: g = 2.0034, AHa = 1.28 mT, AH1=H2 = 1.00 mT, and AH3 = 0.49 mT. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献