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131.
S.N. Menon Bhushan Dhabekar E. Alagu Raja M.P. Chougaonkar 《Radiation measurements》2012,47(3):236-240
LiMgPO4:Tb3+ phosphor was synthesized by solid state reaction. The thermally stimulated luminescence (TSL) glow curve of Tb doped LiMgPO4 exhibits a main TSL peak at 170 °C with shoulders at 100 and 260 °C on either side of this peak. The TSL sensitivity of the phosphor was found to be about 2.5 times that of CaSO4:Dy phosphor. TSL emission and photoluminescence (PL) studies show that Tb3+ ion acts as luminescence centre in this phosphor. The kinetic parameters, namely activation energy (E) and frequency factor (s) associated with the main glow peak have been determined using peak shape method. The activation energy and frequency factor obtained are 1.35 ± 0.03 eV and (6.53 ± 0.43) × 1014 s?1 respectively. The paper discusses the dosimetric characteristics like dose response, fading, energy response and minimum detectable dose and results thereof. 相似文献
132.
D. K. Walters S. Bhushan M. F. Alam D. S. Thompson 《Flow, Turbulence and Combustion》2013,91(3):643-667
This paper investigates a recently proposed dynamic hybrid RANS-LES framework using a general-purpose finite-volume flow solver. The new method is highly generalized, allowing coupling of any selected RANS model with any selected LES model and containing no explicit grid dependence in its formulation. Selected results are presented for three test cases: two-dimensional channel flow, backward facing step, and a nozzle flow relevant to biomedical applications. Comparison with experimental and DNS data, and with other hybrid RANS-LES approaches, highlights the advantages of the new method and suggests that further investigation is warranted. 相似文献
133.
Brij Bhushan Ahuja Arkadi Vigalok 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(9):2800-2804
We present the first fluorescent water‐soluble conjugated calixarene scaffolds that are capable of NO gas detection. Two different scaffolds, one based on a 5,5′‐bicalixarene structure and its isomer bearing two distantly conjugated calixarene moieties, were synthesized. While the fluorescence of both isomers is quenched upon either passing of NO gas or generating it in situ from diethylamine NONOate, the bicalixarene‐based scaffold showed a significantly stronger response. We also present an example of a dye encapsulation strategy to achieve the detection of NO at longer wavelengths than in the parent calixarene host. Finally, a conjugated polymer bearing a 5,5′‐bicalixarene scaffold has also been prepared and demonstrated enhanced sensitivity compared to the monomer due to the molecular wire effect. 相似文献
134.
Shikha Kumari Chandra Bhushan Mishra Danish Idrees Amresh Prakash Rajesh Yadav Md. Imtaiyaz Hassan Manisha Tiwari 《Molecular diversity》2017,21(1):163-174
A series of novel 2-(4-(4-substituted piperazin-1-yl)benzylidene)hydrazinecarboxamide derivatives has been successfully designed and synthesized to evaluate their potential as carbonic anhydrase (CA) inhibitors. The inhibitory potential of synthesized compounds against human CAI and CAII was evaluated. Compounds 3a–n exhibited \(\hbox {IC}_{50}\) values between \(1.89{-}415.1\,\upmu \hbox {M}\) against CAI and \(0.62{-}66.9\,\upmu \hbox {M}\) against CAII. Compound 3g was the most active inhibitor, with an \(\hbox {IC}_{50}\) value of \(0.62\,\upmu \hbox {M}\) against CAII. Molecular docking studies of compound 3g with CAII showed this compound fits nicely in the active site of CAII and it interacts with the zinc ion (\(\hbox {Zn}^{2+}\)) along with three histidine residues in the active site. Molecular dynamics simulation studies of compound 3g complexed with CAII also showed essential interactions which were maintained up to 40 ns of simulation. In vivo sub-acute toxicity study using 3g (300 mg/kg) was found non-toxic in adult Wistar rats. 相似文献
135.
136.
JPC – Journal of Planar Chromatography – Modern TLC - Direct enantioresolution of (±)-etodolac has been achieved by adopting a new conceptual approach involving both achiral phases... 相似文献
137.
Static model coefficients for an algebraic subgrid stress (SGS) model are determined using a dynamic approach, based on results from simulations of isotropic decaying turbulence. The study was motivated by the discrepancies in energy transfer predictions using the previously documented coefficients (Bhushan and Warsi, Int. J. Numer. Meth. Fluids 2005; 49 : 489–519). The discrepancies are identified to be due to inconsistent filter functions used in the analytic estimates and the simulations. The study emphasizes that SGS model development should use filter functions compatible with those inherent in CFD application solvers. The dynamic approach predicts consistent model and transfer coefficients for different grid resolutions and is judged to be a reliable basis for model coefficient adjustments. The predicted Leonard's stress coefficient and associated energy transfer coefficients agree very well with the analytic estimates using a Gaussian/cutoff combination filter. This suggests that the modeling of Leonard's stress term using a truncated Taylor series expansion is robust and may not benefit significantly from dynamic modeling. Validation simulations were performed for turbulent channel flow at Reτ = 180 and 590. The dynamic approach was found to be reliable only for the lower log‐layer of the Reτ = 590 case, where the scale invariance condition was satisfied. Nonetheless, in this narrow range, the model and transfer coefficients compare well with the isotropic case. The static coefficient algebraic model with new adjusted coefficients shows improved predictions compared with the previous coefficients, for both isotropic decaying turbulence and channel flow cases. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
138.
The extraction of ammine complexes of Cu2+, Cd2+, Ni2+, Co2+ and Zn2+ by synthesised manganese, nickel and zinc silicates has been studied at different pH and ionic concentrations in the external
solution. It has been found that the uptake of the metal ion Co2+, Cu2+ and Zn2+ increases with increase in pH of the external solution, attains a maximum and then decreases. However, the uptake for Cd2+ and Ni2+ increases continuously. The qA values of all the silicates increases with the increase in the concentration of the exchanging ion and its order for the
investigated metal ions is Ni2+ < Co2+ < Cd2+ < Zn2+ < Cu2+. 相似文献
139.
140.
Narender K. Kaushik Bharat Bhushan Gurdeep R. Chhatwal 《Transition Metal Chemistry》1978,3(1):215-217
Summary Titanium(IV)N,N-dialkyldithiocarbamates of the type 5-Cp2Ti (S2CNR2)Cl and (5-MeCp)2Ti(S2CNR2)Cl (R = Me, Et and i-Pr) have been prepared by the reaction of di--cyclopentadienyldichlorotitanium(IV) and bis-n-methylcyclopentadienyldichlorotitanium(IV) with sodium salts of dithiocarbamic acids in refluxing dichloromethane. Molecular weight, conductance and i.r. studies show these complexes to be monomeric nonelectrolytes in which the dithiocarbamate ligands are bidentate. Therefore, pentacoordination may be assigned to titanium(IV) atom in all six complexes. Electronic and proton n.m.r. studies spectra have also been recorded for the complexes. 相似文献