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411.
利用强子和串级联模型LUCIAE研究了PHOBOS的极限碎裂等以及在PHIC进行的Au+Au碰撞中带电粒子多重性的经验标度规律. 对Φ介子的产生机制也通过与带电粒子多重性的比较进行类似的研究. 结果似乎表明在串级碎裂模型中带电粒子和Φ介子有共同的产生机制. 还讨论了PHOBOS经验标度规律的模型依赖性.The PHOBOS’s limiting fragmentation etc. three empirical scaling rules for charged multiplicity in Au+Au collisions at RHIC are investigated by ahadron and string cascade model LUCIAE. Similar studies are performed for the meson exploring its production mechanism via comparing with the charged multiplicity. The LUCIAE results for charged multiplicity are compatible with PHOBOS observations. However, for the meson the three empirical scaling rules are either kept only or kept better in the LUCIAE calculations without reduction mechanism of the s quark suppression extra introduced for the strangeness in LUCIAE model. These results seem indicating a universal production mechanism for charged particle and meson in string fragmentation regime. It is discussed that the PHOBOS’s empirical scaling rules are model dependent indeed. 相似文献
412.
We present the simulation results of the net charge fluctuation in Au Au collisions at /Snn=130 GeV froma dynamic model, JPCIAE, and its revisions. The simulations are done for the quark-gluon matter, the directly producedpions, the pion matter, and the hadron matter. The simulated net charge fluctuation of the quark-gluon matter is closeto the thermal model prediction for the quark-gluon gas. However, the discrepancy exists comparing the simulated netcharge fluctuation for directly produced pions and the pion matter with the thermal model prediction for pion gas andthe resonance pion gas, respectively. The net charge fluctuation of hadron matter from default JPCIAE simulations isnearly 3.5 times larger than quark-gluon matter. A discussion is given for the net charge fluctuation as an evidence ofQGP phase transition. 相似文献
413.
M. A. Knyazev 《Russian Physics Journal》2005,48(5):483-485
In the present work, the (1+1)-dimensional nonlinear equation of motion of ϕ4 scalar theory is examined with simultaneous allowance for the processes of energy dissipation and pumping in the system.
The energy dissipation is described in the equation by a linear term, and the energy pumping is described by a squared time
derivative of the field. A single-kink solution is constructed for the given problem. It is demonstrated that a scalar field
expansion in the inflationary model can occur with balanced energy dissipation and pumping.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 40–42, May, 2005. 相似文献
414.
415.
A possibility of increasing efficiency of acousto-optic interaction at a wavelength of 10.6 μm by surface plasmon polaritons is investigated. The diffraction of a surface plasmon polariton (excited by a volume beam) on a surface acoustic wave is analyzed and numerically simulated. 相似文献
416.
N. G. Chernorukov Yu. N. Mikhailov A. V. Knyazev A. S. Kanishcheva A. A. Sazonov E. V. Vlasova 《Russian Journal of Coordination Chemistry》2007,33(2):145-148
Rubidium hexanitratothorate was synthesized, and its crystal structure was determined by X-ray diffraction analysis: space group P21/n; a = 8.347(1) Å, b = 6.890(1) Å, c = 13.069(1) Å, β = 91.88(1)°, Z = 2; 1812 independent reflections, R = 0.0165. 相似文献
417.
N. G. Chernorukov N. N. Smirnova A. V. Knyazev M. N. Marochkina A. V. Ershova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(3):337-342
The standard enthalpies of formation of crystalline Ba(BUO5)2 and Ba(BUO5)2 · 2H2O at 298.15 K were determined by reaction calorimetry. The temperature dependences of the heat capacities of these compounds were studied over the temperature range 7–340 K by adiabatic vacuum calorimetry, and their thermodynamic functions were determined. The standard entropies and Gibbs functions of formation of these compounds at 298.15 K were calculated. 相似文献
418.
V. G. Lakhtin S. P. Knyazev L. E. Gusel’nikov E. N. Buravtseva N. A. Kuyantseva I. A. Zalomnova L. A. Parshkova V. G. Bykovchenko A. V. Kisin E. A. Chernyshev 《Russian Journal of General Chemistry》2008,78(9):1668-1674
Unsymmetrical 1,2-bis(diorganylsilyl)ethanes were synthesized by two procedures. Hydrosilylation of chloro(vinyl)silanes were used to obtain compounds of the general formula ClMe2SiCH2CH2SiRMeCl with different substituents (R = Et, Vin, Ph) on the silicon atom. Chlorodealkylation of 1,2-bis(trialkylsilyl)ethanes gave compounds of the general formula ClAlk2SiCH2CH2SiAlk2Cl (Alk = Me, Et, Pr). It is established that the latter reaction provides high yields only with Me-and Et-substituted compounds, whereas Pr-substituted products are formed in poor yields. The mechamism of this reaction based on quantum-chemical calculations is offered. 相似文献
419.
A. P. Sineokov Z. S. Khamidulova D. A. Aronovich A. F. Murokh E. F. Knyazev 《Polymer Science Series D》2008,1(2):91-96
The influence of oligomeric base on the properties of acrylic adhesives and sealants cured by radical mechanism is studied. New anaerobic materials on the basis of oligourethane(meth)acrylates (OUMs) are developed. It is shown that, by adjusting the OUM nature, it is possible to increase the heat and moisture stability of adhesive compositions. As a result of these works, UV-cured adhesive compositions, heat-cured adhesive for bonding untreated aluminum, and two-part adhesive compounds cured at both positive and negative temperatures are developed. 相似文献
420.
The molecular and electronic structures and thermodynamic parameters of 1,2-, 1,7-, and 1,12-dicarba-closo-dodecaborane(12) molecules in the singlet ground state were calculated by the Hartree-Fock, DFT, and MP2 (including B3LYP/6-311G(2d,2p)
and MP2/6-311+G(d,2p) methods). The energies and character of spatial localization of the frontier MOs in o-, m-, p-carboranes(12) correlate with the changes in the configuration stabilities and reactivities in the reactions of carboranes
with electrophilic and nucleophilic agents and bases. The electrostatic potential distributions in the molecules and the atomic
charge distribution of hydrogen atoms correlate with the known chemical properties of carboranes(12). The thermodynamic parameters
of two isomerization reactions, o-C2B10H12 ⇌ m-C2B10H12 and m-C2B10H12 ⇌ p-C2B10H12, calculated for the temperature range 298–1000 K agree with experimental data within the limits of measuring error. The values
of the electron density and the Laplacian of the electron density at the (3, −1) critical points of the B-H and C-H bonds
correlate with the reactivities of the title compounds.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2074–2080, December, 2006. 相似文献