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151.
In this paper, it is shown that the laser radiation intensity required for complete ionization of vapors produced on an irradiated metal surface can be reduced by more than an order of magnitude through using pulsed laser radiation in combination with microwave radiation. 相似文献
152.
Alexander N. Chernega Georg N. Koidan Anatoly P. Marchenko Anatoly A. Korkin 《Heteroatom Chemistry》1993,4(4):365-368
The molecular structure of 2,2,6,6-tetramethylpiperidinophosphaalkyne was determined by the X-ray structural method. The main geometrical parameters are as follows: PC 1.559(2), N C(sp) 1.316(2) Å, PC N 178.9(1)°, with an almost planar trigonal bond configuration for the N atom and the chair conformation of the piperidine ring. Structural evidence for the nitrogen lone pair conjugation with the π-system of the triple bond was found to be different in phosphaalkynes PC-NR2 and nitriles NC NR2. Quantum-chemical ab initio calculations (HF/631G*) showed that this is caused by a different character of polarization of the PC and NC triple bonds. 相似文献
153.
Kumaran Ramanathan Juraj Svitel Anatoli Dzgoev P. V. Sundaram Bengt Danielsson 《Applied biochemistry and biotechnology》2001,96(1-3):287-301
Molecular electronics involves expertise from several branches of science. Various biomaterials and electronics are involved
in the fabrication of such devices. While passive biomaterials are involved in anchoring the active biomolecules, the latter
are involved in switching and/or signal transduction. In the present investigation we have used a glass-capillary-based approach
to design a biosensor for retinol. The sensing element is retinol-binding protein (RBP). The affinity of retinoic-acid-horseradish
peroxidase (conjugate) to RBP is tested using a surface plasmon resonance technique. A simple photomultiplier-tube-based system
is exploited to monitor the chemiluminescent signal generated upon reaction of hydrogen peroxide and luminol with the conjugate
bound to RBP. The photomultiplier tube is directly coupled to a computer for data logging. 相似文献
154.
Anatoli Polkovnikov 《Annals of Physics》2010,325(8):1790-1852
We discuss a phase space representation of quantum dynamics of systems with many degrees of freedom. This representation is based on a perturbative expansion in quantum fluctuations around one of the classical limits. We explicitly analyze expansions around three such limits: (i) corpuscular or Newtonian limit in the coordinate-momentum representation, (ii) wave or Gross-Pitaevskii limit for interacting bosons in the coherent state representation, and (iii) Bloch limit for the spin systems. We discuss both the semiclassical (truncated Wigner) approximation and further quantum corrections appearing in the form of either stochastic quantum jumps along the classical trajectories or the nonlinear response to such jumps. We also discuss how quantum jumps naturally emerge in the analysis of non-equal time correlation functions. This representation of quantum dynamics is closely related to the phase space methods based on the Wigner-Weyl quantization and to the Keldysh technique. We show how such concepts as the Wigner function, Weyl symbol, Moyal product, Bopp operators, and others automatically emerge from the Feynmann's path integral representation of the evolution in the Heisenberg representation. We illustrate the applicability of this expansion with various examples mostly in the context of cold atom systems including sine-Gordon model, one- and two-dimensional Bose-Hubbard model, Dicke model and others. 相似文献
155.
Probing the effect of anion structure on the physical properties of cationic 1,2,3‐triazolium‐based poly(ionic liquid)s
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Mona M. Obadia Sébastien Fagour Yakov S. Vygodskii Frédéric Vidal Anatoli Serghei Alexander S. Shaplov Eric Drockenmuller 《Journal of polymer science. Part A, Polymer chemistry》2016,54(14):2191-2199
To extensively explore the influence of anion structure on the physical properties of poly(ionic liquid)s (PILs) a series of PILs having main‐chain 1,2,3‐triazolium cations was synthesized via copper(I)‐catalyzed azide‐alkyne 1,3‐dipolar cycloaddition (CuAAC) followed by N‐alkylation with iodomethane and anion metathesis with different metal salts, that is, Li(CF3SO2)2N, Li(CF3CF2SO2)2N, K(FSO2)2N, K(CF3SO2)N(CN), Ag(CN)2N, and sodium 4,5‐dicyano‐1,2,3‐triazolate. To isolate the effect of anion on physical properties of PILs, a common iodide precursor was used to maintain constant the average degree of polymerization (DPn) and chain dispersity. Detailed structure/properties relationship analyses demonstrated a lack of correlation between anion chemical structure, ionic conductivity, and glass transition temperatures. Among synthesized series, the PIL derivative having bis(trifluoromethylsulfonyl)imide counter anion showed the best compromise in performance: low glass transition temperature (Tg = ?68 °C), high thermal stability (Tonset = 340 °C) and superior ionic conductivity (σDC = 8.5 × 10? 6 S/cm at 30 °C), which makes it an interesting candidate for various key modern electrochemical applications. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2191–2199 相似文献
156.
157.
V. N. Gurin S. P. Nikanorov M. P. Volkov L. I. Derkachenko T. B. Popova I. V. Korkin B. R. Willcox L. L. Regel’ 《Technical Physics》2005,50(3):341-346
Crystallization in the Al-Si, Al-Ge, and Al-Si-Ge systems at centrifugation is studied. Of them, the Al-Si system is the least
prone to sedimentation. In the others, sedimentation considerably changes the structure of the alloys at the bottom of the
ingots compared with their top. At certain concentrations of the constituents, the number of crystallites in the lower part
of the ingot is larger than in the upper part and the crystallites at the bottom are coarser than at the top. The Si: Ge atomic
ratio in the Al-Si-Ge system changes by a factor of 2–12 against the initial ratio (1: 1) when the (Si + Ge) concentration
changes as a result of centrifugation. Also, this ratio changes over the crystal surface (in the samples not subjected to
centrifugation, this ratio remains unchanged over the surface). Crystallites in the Al-Si-Ge system are covered by Ge. 相似文献
158.
We introduce the difference in quantum mutual information for a bipartite system of qubits and the minimum taken with respect to the local unitary transformation group as a characteristic of quantum correlations of the system tomographic mutual information. We study in detail the example of two qubits and the X state of two qubits. 相似文献
159.
V.P. Budak S.V. Korkin 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(8):1347-1362
The paper deals with the polarized radiative transfer within a slab irradiated by a collimated infinitely wide beam of arbitrary polarized light. The efficiency of the proposed analytical solution lies in the assumption that the complete vectorial radiative transfer solution is the superposition of the most anisotropic and smooth parts, computed separately. The vectorial small-angle modification of the spherical harmonics method is used to evaluate the anisotropic part, and the vectorial discrete ordinates method is used to obtain the smooth one. The azimuthal expansion is used in order to describe the light field spatial distribution for the case of abnormal irradiance and to obtain some known neutral points in the sky especially useful for polarized remote sensing of the atmosphere. 相似文献
160.
M/G/1 type queueing systems whose arrival rate is a function of an independent continuous time Markov chain are considered.
We suggest a simple analytical approach which allows rigorous mathematical analysis of the stationary characteristics under
heavy traffic. Their asymptotic behaviour is described in terms of characteristics of the modulating process (defined as a
solution of a set of linear algebraic equations). The analysis is based on certain “semi-explicit” formulas for the performance
characteristics.
This research was supported by INTAS under grant No. 96-0828. 相似文献