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排序方式: 共有190条查询结果,搜索用时 15 毫秒
101.
R. N. Santra T. K. Chaki P. G. Mukunda G. B. Nando 《Journal of Thermal Analysis and Calorimetry》1995,44(6):1401-1415
Curing reactions of ethylene methyl acrylate (EMA) polydimethyl siloxane (PDMS) rubber blends have been investigated by differential
scanning calorimetry (DSC) and by Rheometry. The curing exoterms obtained from DSC curves have been analysed to derive the
kinetic parameters associated with the curing process. Crosslinking of EMA-PDMS rubber blends follow first order kinetics.
The effect of blend ratio and peroxide concentration on the crosslinking characteristics of the blends have also been investigated.
Department of Metallurgical Engineering 相似文献
102.
103.
Using the large and chemically diverse GMTKN55 dataset, we have tested the performance of pure and hybrid KS-DFT and HF-DFT functionals constructed from three variants of the SCAN meta-GGA exchange-correlation functional: original SCAN, rSCAN, and r2SCAN. Without any dispersion correction involved, HF-SCANn outperforms the two other HF-DFT functionals. In contrast, among the self-consistent variants, SCANn and r2SCANn offer essentially the same performance at lower percentages of HF-exchange, while at higher percentages, SCANn marginally outperforms r2SCANn and rSCANn. However, with D4 dispersion correction included, all three HF-DFT-D4 variants perform similarly, and among the self-consistent counterparts, r2SCANn-D4 outperforms the other two variants across the board. In view of the much milder grid dependence of r2SCAN vs. SCAN, r2SCAN is to be preferred across the board, also in HF-DFT and hybrid KS-DFT contexts. 相似文献
104.
Dhananjay Bhattacherjee Igor S. Kovalev Dmitry S. Kopchuk Matiur Rahman Sougata Santra Grigory V. Zyryanov Pralay Das Rituraj Purohit Vladimir L. Rusinov Oleg N. Chupakhin 《Molecules (Basel, Switzerland)》2022,27(22)
Highly regiospecific, copper-salt-free and neat conditions have been demonstrated for the 1,3-dipolar azide-alkyne cycloaddition (AAC) reactions under mechanochemical conditions. A group of structurally challenging alkynes and heterocyclic derivatives was efficiently implemented to achieve highly functionalized 1,4-disubstituted-1,2,3-triazoles in good to excellent yield by using the Cu beads without generation of unwanted byproducts. Furthermore, the high-speed ball milling (HSBM) strategy has also been extended to the synthesis of the commercially available pharmaceutical agent, Rufinamide, an antiepileptic drug (AED) and its analogues. The same strategy was also applied for the synthesis of the Cl-derivative of Rufinamide. Analysis of the single crystal XRD data of the triazole was also performed for the final structural confirmation. The Cu beads are easily recoverable from the reaction mixture and used for the further reactions without any special treatment. 相似文献
105.
Savchuk Maria I. Kopchuk Dmitry S. Taniya Olga S. Nikonov Igor L. Egorov Ilya N. Santra Sougata Zyryanov Grigory V. Chupakhin Oleg N. Charushin Valery N. 《Journal of fluorescence》2021,31(4):1099-1111
Journal of Fluorescence - A PASE (pot, step, atom, economic) synthetic approach to 5-aryl-6-arylthio-2,2′-bipyridine and 6-arylthio-2,5-diarylpyridine ligands/fluorophores has been reported... 相似文献
106.
107.
S. Chhillar R. Acharya S. Sodaye K. Sudarshan S. Santra R. K. Mishra C. P. Kaushik R. K. Choudhury P. K. Pujari 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(1):115-119
Barium borosilicate glass (BaBSG) is proposed as a potential candidate for vitrification of nuclear waste generated from thoria based nuclear reactors. Along with fission products, activation products and many inactive chemicals, like fluorine in the form of HF are expected to be present in the dissolver solution with nuclear waste. As vitrification occurs at high temperature, it is important to quantify fluorine in BaBSG. Due to its complex matrix, most of the wet chemical and nuclear analytical methods encounter problems in the estimation of fluorine. Particle induced γ-ray emission (PIGE) method has been standardized for non-destructive determination of fluorine contents in BaBSG samples utilizing measurement of prompt gamma-rays from 19F (p, p’γ) 19F reaction. Experiments have been carried out with thick pellet targets prepared in cellulose matrix using 4 MeV proton beam from the folded tandem ion accelerator at BARC, Mumbai. For obtaining current normalized count rate of interest, beam current variation was monitored by the Rutherford backscattering spectrometry (RBS) method as well as by the in situ approach using an externally added element sensitive to PIGE. In this paper standardization of PIGE methods for F determination, validation of methods using synthetic samples, and application to BaBSG samples are reported. 相似文献
108.
A ratiometric fluorescent probe for mercury species is developed based on the metal-promoted hydrolysis of a vinyl ether derivative of 2-(benzothiazol-2-yl)phenol in a buffer solution. The probe responds selectively to mercury species over various other metal ions with a marked fluorescence change from blue to cyan through the excited state intramolecular proton transfer (ESIPT) process. The fluorescence titration is complete with 0.5 equiv of HgCl(2), which indicates that the probe also responds to organomercury species, RHgCl. 相似文献
109.
Subenoy?ChakrabortyEmail author Batul?Chandra?Santra Nabajit?Chakravarty 《Pramana》2003,61(4):669-673
In this paper generalized scalar tensor theory has been considered in the background of anisotropic cosmological models, namely,
axially symmetric Bianchi-I, Bianchi-III and Kortowski-Sachs space-time. For bulk viscous fluid, both exponential and power-law
solutions have been studied and some assumptions among the physical parameters and solutions have been discussed. 相似文献
110.
Santra B Klimeš J Alfè D Tkatchenko A Slater B Michaelides A Car R Scheffler M 《Physical review letters》2011,107(18):185701
The first principles methods, density-functional theory and quantum Monte Carlo, have been used to examine the balance between van der Waals (vdW) forces and hydrogen bonding in ambient and high-pressure phases of ice. At higher pressure, the contribution to the lattice energy from vdW increases and that from hydrogen bonding decreases, leading vdW to have a substantial effect on the transition pressures between the crystalline ice phases. An important consequence, likely to be of relevance to molecular crystals in general, is that transition pressures obtained from density-functional theory exchange-correlation functionals which neglect vdW forces are greatly overestimated. 相似文献