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51.
Imgon Hwang Seulgi So Mohamed Mokhtar Abdelmohsen Alshehri Shaeel A. Al‐Thabaiti Dr. Anca Mazare Prof. Patrik Schmuki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9204-9208
In the present work we report significant enhancement of the photoelectrochemical properties of self‐ organized TiO2 nanotubes by a combined “de‐coring” of classic nanotubes followed by an appropiate TiCl4 treatment. We show that, except for the expected particle decoration, a key effect of the TiCl4 treatment is that the electron transport characteristics in TiO2 nanotubes can be drastically improved, for example, we observe an enhancement of up to 70 % in electron‐transport times. 相似文献
52.
Anca Dumbravă Rodica Olar Mihaela Badea Maria Nicoleta Grecu Florentina Pătrascu Luminita Măruţescu Nicolae Stănică 《Journal of Thermal Analysis and Calorimetry》2014,115(3):2447-2455
New complexes ML(CNS)·nH2O [M = Ni, n = 0.5; M = Cu, n = 4.5; M = Zn, n = 0.5, HL: 6-mercapto-(1,4,8,11-tetraazaundecanyl)-6-carboxylic acid)] have been synthesised, chemical analysed, and characterised by different spectroscopic techniques (IR, UV–Vis–NIR, 1H NMR, EPR, ESI–MS), and magnetic measurements. Based on the IR spectra a dinuclear structure with the 1,3-CSN coordination was proposed for Ni(II) and Cu(II) complexes. The dinuclear structure of Cu(II) complex is also consistent with both magnetic behaviour and EPR spectrum. According to TG, DTG and DTA curves the thermal transformations are complex processes, including dehydration, Mannich base oxidative degradation and thiocyanate decomposition. The final product of decomposition is the most stable metallic oxide, as XRD data indicates. The new complexes were also screened for their microbicidal and antibiofilm properties. 相似文献
53.
Alpar Pöllnitz Anca Silvestru Cristian Silvestru 《Journal of organometallic chemistry》2010,695(23):2486-2492
Diorganodiselenide [2-(Et2NCH2)C6H4]2Se2 (1) was obtained by hydrolysis/oxidation of the corresponding [2-(Et2NCH2)C6H4]SeLi derivative. The treatment of [2-(Et2NCH2)C6H4]2Se2 with elemental sodium in THF resulted in [2-(Et2NCH2)C6H4]SeNa (2). Reactions between alkali metal selenolates [2-(R2NCH2)C6H4]SeM′ (R = Me, Et; M′ = Li, Na) and MCl2 (M = Zn, Cd) in a 2:1 molar ratio resulted in the [2-(R2NCH2)C6H4Se]2M species [R = Me, M = Zn (3), Cd (4); R = Et, M = Zn (5), Cd (6)]. The new compounds were characterized by multinuclear NMR (1H, 13C, 77Se, 113Cd) and mass spectrometry. The crystal and molecular structures of 1, 3 and 4 revealed monomeric species stabilized by N → Se (for 1) and N → M (for 3 and 4) intramolecular interactions. 相似文献
54.
Opris LM Silvestru A Silvestru C Breunig HJ Lork E 《Dalton transactions (Cambridge, England : 2003)》2004,(21):3575-3585
The cyclostibane R(4)Sb(4)(1)(R = 2-(Me(2)NCH(2))C(6)H(4)) was synthesized by reduction of RSbCl(2) with Mg in THF or with Na in liquid NH(3). The reaction of 1 with [W(CO)(5)(THF)] gives the stibinidene complex RSb[W(CO)(5)](2)(2). RSbCl(2) and (RSbCl)(2)E [E = O (6), E = S (8)] react with KOH or Na(2)S in toluene/water to give the heterocycles (RSbE)(n)[E = O, n= 3 (3); E = S, n= 2 (4)]. The chalcogeno-bridged compounds of the type (RSbCl)(2)E [E = O (6), E = S (8)] were synthesized by reaction of RSbCl(2) with KOH or Na(2)S in toluene/water, but also by reaction of RSbCl(2) with the heterocycles (RSbE)(n). The compounds (RSbI)(2)O (7) and (RSbBr)(2)S (9) were prepared via halogen-exchange reactions between (RSbCl)(2)E and NaI (E = O) or KBr (E = S) or by reactions between RSbI(2) and KOH or RSbBr(2) and Na(2)S. The reaction of cyclo-(RSbS)(2) with W(CO)(5)(THF) in THF results in trapping of the cis isomer in cyclo-(RSbS)(2)[W(CO)(5)](5). The solution behaviour of the compounds was investigated by (1)H and (13)C NMR spectroscopy. The molecular structures of compounds 1-7 and 9 were determined by single-crystal X-ray diffraction. 相似文献
55.
Dragulescu-Andrasi A Rapireddy S He G Bhattacharya B Hyldig-Nielsen JJ Zon G Ly DH 《Journal of the American Chemical Society》2006,128(50):16104-16112
56.
Lipid diffusion from single molecules of a labeled protein undergoing dynamic association with giant unilamellar vesicles and supported bilayers 总被引:1,自引:0,他引:1
Sharonov A Bandichhor R Burgess K Petrescu AD Schroeder F Kier AB Hochstrasser RM 《Langmuir : the ACS journal of surfaces and colloids》2008,24(3):844-850
It is demonstrated that single-molecule tracking of a fluorescently labeled protein undergoing transient binding to model membranes presents a useful method of obtaining fluid properties. The labeled ACBP protein was tracked during its binding to free-standing giant unilamellar vesicles (GUVs) and supported bilayers prepared from the GUVs in the same environment. The analysis of images that are blurred as a result of fast probe diffusion was discussed. An examination of the lateral diffusion trajectories revealed a homogeneous diffusion on the top segments of the GUVs with D = 6.9 +/- 0.3 microm(2)/s. The supported bilayer experiments revealed two diffusion processes, one with Df = 3.1 +/- 0.4 microm(2)/s and the other with Ds = 0.078 +/- 0.001 microm(2)/s. The 2-fold difference in the lipid bilayer mobility for the free-standing and fast components in the supported bilayers is attributed to the known effect of frictional coupling with the solid support. The slow mobile fraction in the bilayer is suggested to be associated with the migration of pore-like structures, originating from the interaction of the membrane with the glass support. 相似文献
57.
Adina Morozan Anca Dumitru Claudia Nastase Florin Nastase Ioan Stamatin 《Macromolecular Symposia》2008,267(1):129-133
Confidence in the potential of hydrogen as an energy vector and fuel bring the opportunities for enhancing electrolyzer performance. The aim of this paper is to develop new polymer nanocomposites as electrolyte membranes for PEM-electrolyzer. A series of nanocomposite membranes, including GEFC/TiO2, GEFC/CNTs, and GEFC/TiO2CNTs have been developed and characterized by FT-IR spectroscopy and AFM. The application of polymer nanocomposite membranes in electrochemical cells for water electrolysis was investigated. Experimental results obtained with respect to performance are reported and discussed related to GEFC membrane. 相似文献
58.
Sá J Kartusch C Makosch M Paun C van Bokhoven JA Kleymenov E Szlachetko J Nachtegaal M Manyar HG Hardacre C 《Chemical communications (Cambridge, England)》2011,47(23):6590-6592
Determination of metal oxidation state under relevant working conditions is crucial to understand catalytic behaviour. The reduction behaviour of Pt and Re was evaluated simultaneously as a function of support and solvent in a pressurized reactor (autoclave). The bimetallic catalysts are used in selective hydrogenation of carboxylic acids and amides. Gas phase reduction reduced the metals more efficiently, in particular Pt. 相似文献
59.
The aim of this paper is to obtain high efficient and inexpensive spectral selective solar absorbers, for solar thermal flat plat collectors using a simple technique – spray pyrolysis deposition (SPD). To achieve maximum solar absorptance and minimum thermal emittance, the following parameters are optimized: the precursor solution concentration and composition, substrate temperature and annealing treatment. The structural and morphological properties of the films were investigated by X-ray diffraction, atomic force microscopy and contact angle measurements. The thermal emittance and solar absorptance of as-deposited films were correlated with the chemical composition, crystalline structure and morphology. The results prove that coatings with excellent spectral selective properties (normal solar absorptance of 0.92 and a normal thermal emittance of 0.03) can be obtained by SPD. 相似文献
60.
Răzvan Şuteu Ciprian I. Raţ Cristian Silvestru Andrada Simion Natalia Candu Vasile I. Pârvulescu Anca Silvestru 《应用有机金属化学》2020,34(4):e5393
The compounds [2-(Me2NCH2)C6H4]2SbL (L = ONO2 ( 2 ), OSO2CF3 ( 3 )) and [PhCH2N(CH2C6H4)2]SbL (L = ONO2 ( 5 ), OSO2CF3 ( 6 )) were prepared by reacting [2-(Me2NCH2)C6H4]2SbCl ( 1 ) and [PhCH2N(CH2C6H4)2]SbCl ( 4 ), respectively, with the appropriate silver(I) salt in a 1:1 molar ratio. The new species 2 – 6 were structurally characterized in solution using multinuclear NMR and in the solid state using infrared spectroscopy. The solid-state structures for compounds 2 , 4 and 6, as well as for the hydrolysis ionic product [{2-(Me2N+HCH2)C6H4}{2-(Me2NCH2)C6H4}SbOH][CF3SO3]− ( 3h ) were determined using single-crystal X-ray diffraction. Medium to strong intramolecular N→ Sb interactions were observed in all these four compounds, thus resulting in hypercoordinated organoantimony(III) species 14-Sb-6 in 2 and 10-Sb-4 in the cation of 3h and in 4 and 6 . Compounds 1 – 6 and the starting amines PhCH2NMe2 and PhCH2N(CH2C6H4Br-2)2 were investigated as catalysts in the Henry (nitroaldol) addition of nitromethane to benzaldehyde. The activity of compounds 1 – 6 resulted as an effect of the cooperation of the positively charged antimony with the negatively charged nitrogen. 相似文献