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31.
Marcelle Gaune-Escard A. Bogacz L. Rycerz W. Szczepaniak 《Journal of Thermal Analysis and Calorimetry》1995,45(5):1117-1124
Present work is a part of thermodynamic research program on the MX?LnX3 system (M=alkali metal,X=Cl, Br andLn=lanthanide). Molar enthalpies of mixing in the LiBr?NdBr3, NaBr?NdBr3 and KBr?NdBr3 liquid binary systems have been determined at temperature 1063 K by direct calorimetry in the whole range of composition. Investigated systems are generally characterized by negative enthalpies of mixing with minimum atX NdBr3≈0.3–0.4. These enthalpies decrease with decrease of ionic radii of alkali metals. Molar enthalpies of solid-solid and solid-liquid phase transitions of K3NdBr6 and Cs3NdBr6 have been also determined by differential scanning calorimetry (DSC). K3NdBr6 is formed at 689 K from KBr and K2NdBr5 with enthalpy of 44.0 kJ·mol?1 whereas Cs3NdBr6 is stable at ambient temperature and undergoes phase transition in the solid state at 731 K with enthalpy of 8.8 kJ·mol?1. Enthalpies of melting have been also determined. 相似文献
32.
Yu-Ming ZHENG Hong-Min LIU Ben-Hao SA Zhong-Dao LU Zhong-Qi WANG Xiao-Ze ZHANG 《理论物理通讯》1993,19(1):71-74
A simple Monte Carlo simulation and even a partition method can be used to reproduce quite well the power law behavior between the factorial moment and the charge interval of fragment charge distributions from the multifragmentation of 197Au nucleus bombarding emulsion at~1 GeV/nucleon. This indicates that the above power law seems not to be a unique precursor of the intermittent behavior in nuclear multifragmentations. 相似文献
33.
Following the method developed by the authors,recently,the equation of state of hot nuclei(238U in concrete) before break-up was investigated numerically.The isotherms are drawn in the plan of the general pressure P versus volume VRT. They are similar to those of Van der Waals gas.The critical temperature of phase transition should correspond to the isotherm with one turning point only.It turns out that the data of mass yield distribution can be reproduced by many pairs of parameters T and VRT (freeze-out temperature and freeze-out volume) varying in certain range.For each isotherm (each T),the data are always best reproduced by the value of VRT located at the maximum general pressure within two phases coexistence region. 相似文献
34.
35.
The φ meson productions in Au+Au and/or Pb+Pb collisions at AGS, SPS,
RHIC, and LHC energies have been studied systematically with a hadron and
string cascade model LUCIAE. After considering the energy dependence of the
model parameter α in string fragmentation function and adjusting it
to the experimental data of charged multiplicity to a certain extent,
the model predictions for φ meson yield, rapidity, and
transverse mass distributions are compatible with the experimental data at
AGS, SPS and RHIC energies. A calculation for Pb+Pb collisions at LHC energy
is given as well. The obtained fractional variable in string fragmentation
function shows a saturation in energy dependence. It is discussed that the
saturation of fractional variable in string fragmentation function might be a
qualitative representation of the energy dependence of nuclear transparency. 相似文献
36.
The energy and centrality dependencies of charged particle pseudorapidity density in relativistic nuclearcollisions were studied using a hadron and string cascade model, JPCIAE. Both the relativistic p+p experimental dataand the PHOBOS and PHENIX Au+Au data at RHIC energy could be fairly reproduced within the framework ofJPCIAE model and without retuning the model parameters. The predictions for Pb + Pb collisions at the LHC energywere also given. We computed the participant nucleon distributions using different methods. It was found that thenumber of participant nucleons is not a well defined variable both experimentally and theoretically. Thus it may beinappropriate to use the charged particle pseudorapidity density per participant pair .as a function of the number ofparticipant nucleons for distinguishing various theoretical models. 相似文献
37.
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39.
GUY BOUCHITTÉ IRENE FONSECA GIOVANNI LEONI LUÍSA MASCARENHAS 《Archive for Rational Mechanics and Analysis》2002,165(3):187-242
An integral representation formula for a class of functionals defined on and in (the space of special functions of bounded variation) is obtained without requiring the regularity conditions usually imposed
in the literature. The approach is based on the general results of [10] and on a Poincaré-Wirtinger type inequality introduced
by DE GIORGI, CARRIERO & LEACI [25]. Applications to relaxation problems and dimension-reduction problems in brittle thin
films are presented.
(Accepted May 8, 2002) Published online October 18, 2002
Communicated by L. Ambrosio 相似文献
40.
The free in-plane vibrations of circular rings with wheel-plates as generalised elastic foundations are studied using analytical methods and numerical simulations. The three-parameter Winkler elastic layer is proposed as a mathematical model of the foundation. The effects of rotary inertia and shear deformation are included in the analytical model of the system. The motion equations of systems are derived on the basis of the thin ring theory and Timoshenko?s theory. The separation of variables method is used to find general solutions to the free vibrations. Elaborated analytical models are used to determine the natural frequencies and the natural mode shapes of vibrations of an arbitrarily chosen set of simplified models of aviation gears and railway wheels. The eigenvalue problem is formulated and solved by using a finite element representation for each simplified model. The results for these models are discussed and compared. The proposed solutions are verified by experimental investigation. It is important to note that the solutions proposed here could be useful to engineers dealing with the dynamics of aviation gears, railway wheels and other circular ring systems. 相似文献