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71.
Kesavan K. Ravisankar K. Senthil R. Arun Sundaram B. Parivallal S. 《Experimental Techniques》2015,39(5):21-29
Experimental Techniques - Fiber-reinforced polymer (FRP) composite materials are very attractive for use in strengthening of civil engineering structures because of their high strength to weight... 相似文献
72.
An Iron‐Catalyzed Cascade Approach to Benzo[b]carbazole Synthesis Followed by 1,4‐Sulfonyl Migration
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Siva Senthil Kumar Boominathan Gopal Chandru Senadi Dr. Jaya Kishore Vandavasi Dr. Jeff Yi‐Fu Chen Prof. Dr. Jeh‐Jeng Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3193-3197
A simple and straightforward approach was developed to construct 5H‐benzo[b]carbazole derivatives by iron catalysis in a cascade sequence. The notable features of this work include an atom‐economical cascade sequence, unprecedented 1,4‐sulfonyl migration, tolerance of a variety of functional groups, good yields, and an economical catalytic system. 相似文献
73.
A series of regioisomers of pyrazolyl-substituted quinolines has been synthesized through the simple condensation reaction between hydrazinylquinolines with aliphatic 1,3-diketones with InCl3 as a catalyst under microwave irradiation. This method produces pure products in good yield in a rapid manner compared to conventional procedures and withneat reaction condition. The approach has the advantages of operational simplicity and increased safety for a shortened synthesis of pyrazolyl-substituted quinolines. 相似文献
74.
P. Karthikeyan S. Chidambara Raja A. P. Senthil Kumar B. Selvakumar V. Prabhu Raja R. Sankaranand 《Heat and Mass Transfer》2013,49(4):451-467
In this article, the development of geometry dependent resistance model by considering contact resistance and natural convection effects are used to estimate the effective thermal conductivity of two-phase materials based on the unit cell approach. The algebraic equations have been derived based on isotherm approach for 2-D and 3-D spatially periodic medium. Comparison study has been made between developed models and experimental data. The result agrees well with experimental values. 相似文献
75.
76.
Bithiophene triarylborane dyad: An efficient material for the selective detection of CN− and F− ions
Sakthivel Perumal Sekar Karuppannan Sivaraman Gandhi Singaravadivel Subramanian Anbu Govindasamy Senthil Kumar Gopal 《应用有机金属化学》2020,34(1):e5257
A new fluorescent chemosensor based on bithiophene coupled dimesitylborane (BMB-1) was synthesized and characterized. BMB-1 was used for colorimetric and turn-on fluorescent sensing of cyanide (CN−) and fluoride (F−) ions, in the presence of other competitive anions in an aqueous (CH3CN–H2O) medium. BMB-1 showed a hypsochromic shift (blue shift) with addition of CN− and F− ions in absorption studies. The lower detection level of CN− and F− ions is 1.37 × 10−9 and 1.75 × 10−9 M, respectively. The BMB-1 binding mechanism is based on the nucleophilic addition of CN− and F− ions in the internal charge transfer transition of bithio moiety to the boranylmesitylene unit, and the color changes were observed under UV light. This result is further confirmed by Fourier transform infrared spectroscopy, mass spectrometry and density functional theory calculations. Also, the BMB-1 probe is found to be a good adsorbent for the removal of F− ions in real water samples using the adsorption technique. 相似文献
77.
78.
Patel Akash Pravinkumar Bhatnagar Divyang kumar Rajendran Senthil Prabhu Sethuramalingam 《Journal of Thermal Analysis and Calorimetry》2022,147(1):675-684
Journal of Thermal Analysis and Calorimetry - Due to the low performance observed during natural convection with fluids such as air and water, nanofluid research was carried out to analyse them for... 相似文献
79.
A new approach was attempted to prepare a chemically modified electrode using Cobalt hexacyanoferrate (CoHCF) as the redox mediator and to study its stability and electrocatalytic activity for ascorbic acid (AA) oxidation. The basic principle underlying the electrode modification is the coordination of cobalt ion with the amino nitrogen of aniline adsorbed on the surface of a graphite rod. This surface was subsequently derivatized with ferrocyanide to get CoHCF film on the electrode surface. The CoHCF modified electrode as prepared above was characterized using cyclic voltammetry. The effect of scan rate, supporting electrolyte and pH of the medium on the performance of the modified electrode was investigated. The CoHCF modified electrode exhibited good electrocatalytic activity towards the oxidation of ascorbic acid and gave a linear response from 5.52 x 10(-5) M to 3.23 x 10(-2) M with a correlation coefficient of 0.9929. The detection limit was found to be 3.33 x 10(-5) M. Hydrodynamic voltammetry and chronoamperometry studies for the oxidation of ascorbic acid were also carried out. The electrode was highly stable and exhibited good reproducibility. This modified electrode was also applied for the determination of ascorbic acid in commercial samples. 相似文献
80.
An electronically push–pull type dimethylaminoazobenzene–fullerene C60 hybrid was designed and synthesized by tailoring N,N‐dimethylaniline as an electron donating auxochrome that intensified charge density on the β‐azonitrogen, and on N‐methylfulleropyrrolidine (NMFP) as an electron acceptor at the 4 and 4′ positions of the azobenzene moiety, respectively. The absorption and charge transfer behavior of the hybrid donor‐bridge‐acceptor dyad were studied experimentally and by performing TD‐DFT calculations. The TD‐DFT predicted charge transfer interactions of the dyad ranging from 747 to 601 nm were experimentally observed in the UV‐vis spectra at 721 nm in toluene and dichloromethane. A 149 mV anodic shift in the first reduction potential of the N?N group of the dyad in comparison with the model aminoazobenzene derivative further supported the phenomenon. Analysis of the charge transfer band through the orbital picture revealed charge displacement from the n(N?N) (nonbonding) and π (N?N) type orbitals centered on the donor part to the purely fullerene centered LUMOs and LUMO+n orbitals, delocalized over the entire molecule. The imposed electronic perturbations on the aminoazobenzene moiety upon coupling it with C60 were analyzed by comparing the TD‐DFT predicted and experimentally observed electronic transition energies of the dyad with the model compounds, NMFP and (E)‐N,N‐dimethyl‐4‐(p‐tolyldiazenyl)aniline (AZNME). The n(N?N) → π*(N?N) and π(N?N) → π*(N?N) transitions of the dyad were bathochromically shifted with a significant charge transfer character. The shifting of π(N?N) → π*(N?N) excitation energy closer to the n → π*(N?N) in comparison with the model aminoazobenzene emphasized the predominant existence of charge separated quinonoid‐like ground state electronic structure. Increasing solvent polarity introduced hyperchromic effect in the π(N?N) → π*(N?N) electronic transition at the expense of transitions involved with benzenic states, and the extent of intensity borrowing was quantified adopting the Gaussian deconvolution method. On a comparative scale, the predicted excitation energies were in reasonable agreement with the observed values, demonstrating the efficiency of TD‐DFT in predicting the localized and the charge transfer nature of transitions involved with large electronically asymmetric molecules with HOMO and LUMO centered on different parts of the molecular framework. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 相似文献