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1.
P. Savitha D. N. Sathyanarayana 《Journal of polymer science. Part A, Polymer chemistry》2005,43(14):3040-3048
Two series of terpolymers, one of o‐/m‐toluidine and aniline with o‐aminobenzoic acid and the other of o‐/m‐toluidine and aniline with m‐aminobenzenesulfonic acid, have been synthesized by oxidative polymerization via an emulsion method with ammonium persulfate as the oxidant and HCl as the external dopant. The terpolymers exhibit excellent solubility and retain the high conductivity (∼1 S cm−1) characteristic of the unsubstituted homopolymer, polyaniline. The terpolymers also possess higher thermal stability than polyaniline. This can be attributed to the presence of internal doping groups and substituents, which introduce flexibility to the otherwise rigid polyaniline backbone. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3040–3048, 2005 相似文献
2.
B. G. Bhaskaran 《Queueing Systems》1986,1(1):103-127
Given conditions, which concern the infinitesimal parameters of two birth and death processes, the processes are constructed on the same probability space such that one process is almost surely larger than the other. Application is made to M/M/s queueing systems. Stochastic comparisons of queue length and virtual waiting time in two M/M/s systems are obtained. 相似文献
3.
James R. Durig Savitha S. Panikar Keith A. GlennYa Ying Zheng Gamil A. Guirgis 《Vibrational Spectroscopy》2011,55(2):250-257
Infrared and Raman spectra (3500-60 cm−1) of gas and/or liquid and solid 1-chloro-1-silacyclopentane (c-C4H8SiClH) have been recorded and the vibrational data indicate the presence of a single conformer with no symmetry which is consistent with the twisted form. Ab initio calculations with a variety of basis sets up to MP2(full)/aug-cc-pVTZ predict the envelope-axial and envelope-equatorial conformers are saddle points with nearly the same energies but much lower in energy than the planar conformer. Density functional theory calculations by the B3LYP method predicts slightly lower energies for the two envelope forms and considerably lower for the planar form. By utilizing the MP2(full)/6-31G(d) calculations the force constants, frequencies, infrared intensities, band contours, Raman activities, and depolarization values have been obtained to support the vibrational assignment. Estimated r0 structural parameters have been obtained from adjusted MP2(full)/6-311 + G(d, p) calculations. These experimental and theoretical results are compared to the corresponding quantities of some other five-membered rings. 相似文献
4.
The liquid phase benzylation of o-xylene with benzyl chloride over rare earth oxide catalysts like CeO2 and Pr2O3 was studied in a batch reactor at atmospheric pressure and 363 K. Surface area, pore volume, DTA, acid strength distribution on the catalyst surface and optimum temperature of the catalyst are reported. 相似文献
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Potential Analysis - We consider the following stochastic partial differential equation, $$\begin{array}{@{}rcl@{}} &&dY_{t} = L^{\ast} Y_{t} dt + A^{\ast} Y_{t} \cdot dB_{t}\\... 相似文献
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T. Savitha S. Selvasekarapandian C. S. Ramya 《Journal of Solid State Electrochemistry》2008,12(7-8):857-860
In the present study, Li x AlZr[PO4]3 (x = 1.8, 2.0, 2.2) has been prepared by the Pechini-type polymerizable precursor method, and structural and electrical analyses have been performed. Formation of the compound has been confirmed from X-ray diffraction pattern. Vibrational analysis has been performed using Fourier transform infrared spectroscopy. Ion transport mechanism has been analyzed using the AC impedance technique. Electrical characterization reveals that the maximum conductivity (4.4 × 10?5S cm?1) has been observed for the sample Li2.2AlZr[PO4]3 at 673K. 相似文献
9.
G. Savitha 《Tetrahedron letters》2008,49(51):7260-7263
Spiro dihydrofuran fluorene derivatives were prepared via [3+2] oxidative cycloaddition of 1,3-dicarbonyl compounds to 9-benzylidene-9H-fluorene and 2-(9H-fluorene-9-ylidene)-1-phenylethanone derivatives mediated by ceric ammonium nitrate. In the case of the reaction of 9-benzylidene-9H-fluorene with acyclic 1,3-dicarbonyl compounds, spiro 2-hydroxytetrahydrofuran fluorene derivatives were obtained. 相似文献
10.
Vijay Shankar Rangasamy Savitha Thayumanasundaram Jean-Pierre Locquet Jin Won Seo 《Ionics》2017,23(3):645-653
Among the various cathode materials explored for sodium-ion batteries (SIBs), NaMn0.33Ni0.33Co0.33O2, with a layered oxide structure, is a promising material due to its high theoretical capacity (240 mAhg?1). We have synthesized NaMn0.33Ni0.33Co0.33O2 using two different types of precursors, namely metal acetates and metal nitrates by the sol-gel method. XRD patterns confirm the formation of a stable phase of the material at 900 °C. Coupled TGA-FTIR analysis was used to optimize the calcination conditions and to understand the hydrolysis and condensation mechanism of the sol-gel precursors. FTIR spectra extracted at different temperatures reveal the polymer network-forming tendency of the acetate ligands whereas the polymerization is inhibited in the nitrate precursors. SEM analysis shows spherical and platelet morphologies of samples synthesized from nitrate and acetate precursors, respectively. Using in situ impedance and galvanostatic charge/discharge studies, we observed that the precursors used to synthesize the cathode material influence the electrochemical properties of the material, as in this case, where we observe a 20 % improvement in terms of capacity by using acetate precursors instead of nitrate precursors. 相似文献