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41.
42.
The disturbance caused by the application of continuous mechanical source on the free surface of a homogeneous, isotropic
elastic half space in the context of the theory of generalized thermoelastic diffusion with one relaxation time parameter
is investigated in the Laplace-Fourier transform domain for a two dimensional problem using eigenvalue approach. The integral
transforms are inverted by using a numerical technique. The expressions for displacement components, stresses, temperature
field, concentration and chemical potential so obtained in the physical domain are computed numerically and illustrated graphically
at different times, for copper like material. As a special case the effect of diffusion on various expressions has also been
obtained analytically and depicted graphically. 相似文献
43.
A new derivative of ursolic acid containing dual functionality was synthesized. Molecular docking studies and in vitro analysis indicated promising COX inhibition potential for the molecule. The synthesis, characterization, in silico and in vitro studies of the molecule are described here. 相似文献
44.
Thayalaraj Christopher Jeyakumar Masilamani Deepa Sambath Baskaran Chinnappan Sivasankar 《应用有机金属化学》2020,34(10):e5811
Activation and cleavage of molecular hydrogen (H2) to proton and hydride is an important task for several reasons, especially as a reagent in hydrogenation. In this scenario, with the support of density-functional theory methods, a novel strategy has been devised for the conversion of coordinated nitride into ammonia using molecular hydrogen in the presence of tri-tert-butylphosphine (PtBu3). The proposed methodology is based on the formation of frustrated Lewis pair (FLP) from [OsVI(tpy)(Cl)2(N)]+ (tpy = 2,2′:6′,2′′-terpyridine ) and PtBu3 followed by reaction with molecular hydrogen to form an FLP–H2 adduct. The FLP–H2 adduct can further undergo H–H bond cleavage heterolytically to produce proton and hydride which can be eventually used for the functionalization of coordinated nitride to ammonia. The calculated energy profile comprising all possible intermediates and transition-state molecules suggests that the proposed reaction pathway is energetically viable at elevated temperatures. 相似文献
45.
Sathya Vijayakumar Deepa Appadurai Sangeetha Lakshmi Kandhan Srinivasadesikan Venkatesan Lee Shyi-Long Padmini Vediappen 《Journal of fluorescence》2022,32(4):1389-1396
Merocyanine dye based fluorescent organic compound has been synthesized for the detection of glutamine. The probe showed remarkable fluorescent intensity with glutamine through ICT (Intermolecular Charge Transfer Mechanism). Hence, it is tested for the detection of glutamine using colorimetric and fluorimetric techniques in physiological and neutral pH (7.2). Under optimized experimental conditions, the probe detects glutamine selectively among other interfering biomolecules. The probe has showed a LOD (lower limit of detection) of 9.6?×?10–8 mol/L at the linear range 0–180 µM towards glutamine. The practical application of the probe is successfully tested in human biofluids.
Graphical abstract46.
47.
Aniol KA Armstrong DS Averett T Benaoum H Bertin PY Burtin E Cahoon J Cates GD Chang CC Chao YC Chen JP Choi S Chudakov E Craver B Cusanno F Decowski P Deepa D Ferdi C Feuerbach RJ Finn JM Frullani S Fuoti K Garibaldi F Gilman R Glamazdin A Gorbenko V Grames JM Hansknecht J Higinbotham DW Holmes R Holmstrom T Humensky TB Ibrahim H de Jager CW Jiang X Kaufman LJ Kelleher A Kolarkar A Kowalski S Kumar KS Lambert D LaViolette P LeRose J Lhuillier D Liyanage N Margaziotis DJ Mazouz M McCormick K 《Physical review letters》2006,96(2):022003
We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from 4He at an average scattering angle = 5.7 degrees and a four-momentum transfer Q2 = 0.091 GeV2 . From these data, for the first time, the strange electric form factor of the nucleon G(E)s can be isolated. The measured asymmetry of A(PV) = (6.72 +/- 0.84(stat) +/- 0.21(syst) x 10(-6) yields a value of G(E)s = -0.038 +/- 0.042(stat) +/- 0.010(syst), consistent with zero. 相似文献
48.
Kim YG Kim JY Vairavapandian D Stickney JL 《The journal of physical chemistry. B》2006,110(36):17998-18006
The growth of Pt nanofilms on well-defined Au(111) electrode surfaces, using electrochemical atomic layer epitaxy (EC-ALE), is described here. EC-ALE is a deposition method based on surface-limited reactions. This report describes the first use of surface-limited redox replacement reactions (SLR(3)) in an EC-ALE cycle to form atomically ordered metal nanofilms. The SLR(3) consisted of the underpotential deposition (UPD) of a copper atomic layer, subsequently replaced by Pt at open circuit, in a Pt cation solution. This SLR(3) was then used a cycle, repeated to grow thicker Pt films. Deposits were studied using a combination of electrochemistry (EC), in-situ scanning tunneling microscopy (STM) using an electrochemical flow cell, and ultrahigh vacuum (UHV) surface studies combined with electrochemistry (UHV-EC). A single redox replacement of upd Cu from a PtCl(4)(2-) solution yielded an incomplete monolayer, though no preferential deposition was observed at step edges. Use of an iodine adlayer, as a surfactant, facilitated the growth of uniformed films. In-situ STM images revealed ordered Au(111)-(square root 3 x square root 3)R30 degrees-iodine structure, with areas partially distorted by Pt nanoislands. After the second application, an ordered Moiré pattern was observed with a spacing consistent with the lattice mismatch between a Pt monolayer and the Au(111) substrate. After application of three or more cycles, a new adlattice, a (3 x 3)-iodine structure, was observed, previously observed for I atoms adsorbed on Pt(111). In addition, five atom adsorbed Pt-I complexes randomly decorated the surface and showed some mobility. These pinwheels, planar PtI(4) complexes, and the ordered (3 x 3)-iodine layer all appeared stable during rinsing with blank solution, free of I(-) and the Pt complex (PtCl(4)(2-)). 相似文献
49.
A poly(3,4‐ethylenedioxypyrrole)–gold nanoparticle (Au)–tungsten oxide (PEDOP–Au@WO3) electrochromic supercapacitor electrode capable of optically modulating solar energy while simultaneously storing/releasing energy (in the form of charge) was fabricated for the first time. WO3 fibers, 50 to 200 nm long and 20 to 60 nm wide, were synthesized by a hydrothermal route and were electrophoretically deposited on a conducting substrate. Au nanoparticles and PEDOP were coated over WO3 to yield the PEDOP–Au@WO3 hybrid electrode. The inclusion of Au in the hybrid was confirmed by X‐ray diffraction, Raman spectroscopy, and energy‐dispersive X‐ray analyses. The nanoscale electronic conductivity, coloration efficiency, and transmission contrast of the hybrid were found to be significantly greater than those of pristine WO3 and PEDOP. The hybrid showed a high specific discharge capacitance of 130 F g?1 during coloration, which was four and ten times greater than the capacitance achieved in WO3 or PEDOP, respectively. We also demonstrate the ability of the PEDOP–Au@WO3 hybrid, relative to pristine PEDOP, to perform as a superior counter electrode in a solar cell, which is attributed to a higher work function. The capacitance and redox switching capability of the hybrid decreases insignificantly with cycling, thus establishing the viability of this multifunction hybrid for next‐generation sustainable devices such as electrochromic psuedocapacitors because it can concurrently conserve and store energy. 相似文献
50.
Estimation of <Superscript>90</Superscript>Sr activity in reprocessed uranium from the PUREX process
S. Ravi A. K. Deepa B. Surekha S. Susheela P. V. Achuthan S. Anil Kumar K. Vijayan U. Jambunathan S. K. Munshi P. K. Dey 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(1):123-126
90Sr estimation in reprocessed uranium was carried out by a series of solvent extraction and carrier precipitation techniques
using strontium and lanthanum carriers. Fuming with HClO4 was used to remove 106Ru as RuO4. Three step solvent extraction with 50% tri-n-butyl phosphate in xylene in presence of small amounts of dibutyl phosphate
and thenoyl trifluoro acetone was carried out to eliminate uranium, plutonium, thorium and protactinium impurities. Lanthanum
oxalate precipitation in acid medium was employed to scavenge the remaining multivalent ions. Strontium was precipitated as
strontium oxalate in alkaline pH and 137 Cs was removed by washing the precipitate with water. A strontium recovery well above 70% was obtained. Final estimation
was carried out by radiometry using end window GM counter after drying the precipitate under an infra red lamp. The same procedure
was extended to the estimation of 90Sr in a diluted sample of the actual spent fuel solution. An additional lanthanum oxalate precipitation step was required
to remove the entire 144Ce impurity from this sample. This modified procedure was employed in the determination of 90Sr in a number of reprocessed uranium samples and the over all precision of the method was found to be well within ±10%. An
additional barium chromate precipitation step was necessary for the analysis of reprocessed uranium samples from high bumup
fuels to eliminate trace amounts of short lived 224Ra produced during the decay of 232U and its daughters as they interfere in the estimation of 90Sr. 相似文献