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81.
We prove the existence of large energy positive solutions for a stationary nonlinear Schrödinger equation with peaks on a Clifford type torus. Here where with for all Each is a function and is defined by the generalized notion of spherical coordinates. The solutions are obtained by a or a process. 相似文献
82.
Fluorescent Detection of 2,4‐DNT and 2,4,6‐TNT in Aqueous Media by Using Simple Water‐Soluble Pyrene Derivatives
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Dr. Igor S. Kovalev Olga S. Taniya Nataliya V. Slovesnova Grigory A. Kim Dr. Sougata Santra Prof. Grigory V. Zyryanov Dr. Dmitry S. Kopchuk Prof. Adinath Majee Prof. Valery N. Charushin Prof. Oleg N. Chupakhin 《化学:亚洲杂志》2016,11(5):775-781
Pyrene‐containing water‐soluble probes for the fluorescent detection of nitroaromatic compounds (NACs), such as explosive components (2,4‐DNT and 2,4,6‐TNT) and herbicides (2,4‐dinitrocresol, 2,4‐DNOC), in aqueous media are reported. In the probes, the introduction of surface‐active hydrophilic “heads” at the periphery of lipophilic (i.e., hydrophobic) pyrene “tails” resulted in the formation of highly fluorescent micelle‐like aggregates/pre‐associates in aqueous solutions at concentrations of ≤10?5 m . The enhanced fluorescence quenching of the herein reported architectures is achieved in the presence of ultra‐trace amounts of TNT or 2,4‐DNT with values of Stern–Volmer quenching constant close to 1×105 m ?1 and a detection limit as low as 182 ppb. The most hydrophilic probes demonstrated higher response to 2,4‐DNT over TNT. Filter paper test strips impregnated with 1×10?5 m solutions of the probes were able to detect TNT, 2,4‐DNT, and other NACs at levels as low as 50 ppb in water. 相似文献
83.
The potassium resonance line (4s-->4p) centered around 770 nm is a major contributor to the optical extinction in the atmospheres of certain classes of brown dwarfs and extrasolar giant planets. The resonance line is significantly broadened by collisions with He and H2, and an accurate calculation of the line profile is needed for astrophysical models of these objects. As a first step, we report an accurate ab initio study of the K+He and K+H2 potential-energy curves correlating to the K 4s and 4p atomic energy levels, together with the dipole moments governing the transitions between these potential-energy curves. The molecular calculations have been carried out using a multireference configuration-interaction method, with the molecular orbitals expanded in a large Gaussian basis set. The transition dipole moments show significant variation with the molecular geometry. Calculations for the K+H2 system have been carried out for a range of H2 orientations and internuclear separations, so that the effect of H2 rotation and vibration may be explicitly included in future calculations of the pressure-broadened line profiles. 相似文献
84.
The technique of Fock space multireference coupled-cluster (FSMRCC) is applied for the first time to the correlated calculation of the energy and width of a shape resonance in an electron-molecule collision. The procedure is based upon combining a complex absorbing potential with FSMRCC theory. Accurate resonance parameters are obtained by solving a small non-Hermitian eigenvalue problem. The potential-energy curve of the (2)Pi(g) state of N2- is calculated using the FSMRCC and multireference configuration-interaction (MRCI) level of theories. Comparison with the single-determinant Hartree-Fock theory indicates that correlation effects are important in determining the behavior of the resonance state. 相似文献
85.
Satyajit Samanta Rana Chatterjee Sachinta Mahato Alakananda Hajra Sougata Santra Grigory V. Zyryanov 《合成通讯》2018,48(14):1857-1866
An efficient and regioselective method was developed for the synthesis of β-(nitrooxy)-substituted amine derivatives by ring-opening of different aziridines with Zn(NO3)2·6H2O without using additives or catalyst. A library of β-(nitrooxy)-substituted amine derivatives having a variety of substituents has been synthesized. Excellent regioselectivity, high yields, clean reaction, ease of product isolation, easily accessible reactants, and solvent-free as well as environment friendly reaction conditions are the notable advantages of the present methodology. The nitrooxy derivative was successfully transformed into hydroxy derivative by simple reduction. Gram-scale synthesis demonstrates the potential applications of the present method. 相似文献
86.
Electronically metastable states can efficiently be investigted using ??2 techniques, such as the complex absorbing potential (CAP) or the stabilization method; but, the study of autodetaching systems is nonetheless far more expensive than the investigation of comparable bound states. The costly step of the ??2 methods for resonances involves the repeated diagonalization of a parameterized Hamilton operator, and in this communication we investigate representations of the needed operators in very small basis set consisting of a few eigenstates of the physical Hamiltonian. It is shown that CAP calculations can indeed be performed using a very small eigenstate basis set, whereas basis sets of comparable size are unsuitable for stabilization calculations. Our results allow us to study the frequently employed energy selection procedure in the context of Siegert energies. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 82: 218–226, 2001 相似文献
87.
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89.
Adinath Majee Shrishnu Kumar KunduSougata Santra Alakananda Hajra 《Tetrahedron letters》2012,53(33):4433-4435
A new method for oxidation of alcohols to carbonyl compounds has been developed using NH2OH·HCl and NaIO4 under mild reaction conditions at room temperature. Application of the method for the synthesis of diiodo compound from α,β-unsaturated carbonyl compound is also described. 相似文献
90.
The white rot fungus Phanerochaete chrysosporium has been identified to be an environmentally useful microorganism for the degradation of various hazardous pollutants, mainly because of its ligninolytic enzyme system, particularly the lignin peroxidase (LiP) secreted by the fungus. In the present work, the behavior of the fungus in liquid medium due to variation in physico-chemical parameters, i.e., glucose concentration, nitrogen concentration, agitation, etc., was studied. Increment of the initial concentration of glucose in the medium increases the biomass growth and LiP activity, when cultured under controlled conditions. The biomass growth and LiP activity by the fungus was modeled following stochastic approach. The behavior of growth and enzyme activity of the fungus observed from the model were found to be in agreement with the experiments qualitatively. 相似文献