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151.
We proceed with our study of increasing self-described sequences F, beginning with 1 and defined by a functional equation In [1] we exhibited the simple solution f (t)=Ct, for some (0,1), of the associated functional-differential equation and we proved that provided <2/(2+d()), where we have the asymtotic equivalence F(m)~ Cm.In the present paper we show that this last result is optimal, in the sense that the self-described sequence defined by |F–1(m)|=F(m)2, that is
for which the boundary case =2/(2+d())(=1/2) holds, does not satisfy F(m) ~ Cm. We also show that the m-th term F(m) of a sequence F for which the boundary case holds is nevertheless of asymptotic order m.Then we investigate the behaviour of self-described sequences F when lies beyond the boundary case. In [1] we established the estimates when is the unique fixed point of a certain associated function. We were only able to prove in general that the latter holds when does not lie beyond the boundary case, however. In the present paper we prove that whenever is the unique fixed point of this function, and in addition we obtain estimates more precise than (*). This applies for instance to the sequence defined by that is
  相似文献   
152.
We developed a new method for the full kinematical reconstruction of the system near its threshold at future linear e + e - colliders. In the core of the method lies likelihood fitting which is designed to improve measurement accuracies of the kinematical variables that specify the final states resulting from decays. The improvement is demonstrated by applying this method to a Monte Carlo sample generated with various experimental effects including beamstrahlung, finite acceptance and resolution of the detector system, etc. In most cases the fit takes a broad non-Gaussian distribution of a given kinematical variable to a nearly Gaussian shape, thereby justifying phenomenological analyses based on simple Gaussian smearing of the parton-level momenta. The standard deviations of the resultant distributions of various kinematical variables are given in order to facilitate such phenomenological analyses. A possible application of the kinematical fitting method and its expected impact are also discussed. Received: 4 March 2003 / Published online: 23 May 2003 RID="a" ID="a" e-mail: ikematsu@post.kek.jp RID="b" ID="b" e-mail: fujiik@jlcuxf.kek.jp RID="c" ID="c" e-mail: hioki@ias.tokushima-u.ac.jp RID="d" ID="d" e-mail: sumino@tuhep.phys.tohoku.ac.jp RID="e" ID="e" e-mail: tohrut@hiroshima-u.ac.jp  相似文献   
153.
Relaxation rates of magnetic moment and charge are discussed for systems showing intermediate valence. The periodic Anderson model and a more realistic model with periodic 4f shells are investigated by the use of the Mori formalism. It is shown that the relaxation of the 4f moment and the charge above the spin fluctuation temperature is dominated by the second order process with respect to the hybridization interaction and is nearly independent of temperature. The moment relaxation rate is significantly larger than that in the integral valent case where the fourth order Korringa process is dominant. The theory can explain the anomalously large width and the momentum independent nature of the quasi-elastic component of the neutron scattering on intermediate valence compounds.Work performed under the research program SFB 125 Aachen-Jülich-KölnOn leave of absence from the Department of Applied Physics, Tohoku University, Sendai 980, Japan  相似文献   
154.
Finite element procedures are developed and verified for layered beams and rings having either continuously or discontinuously constrained viscoelastic damping layers. The two configurations considered are (1) a three-layered sandwich beam or ring (closed curved beam) consisting of two thin elastic layers with a viscoelastic core in between, and (2) a damped composite made of a thin-walled elastic structure having a finite number of mass segments or elastic segments adhered to it by a viscoelastic material. Viscoelastic material dependence on frequency and temperature is accounted for. Numerical predictions of transverse driving point impedances agree very well with available experimental data.  相似文献   
155.
The study of 2699 Å electronic band system of chlorobenzene has been extended to extract out all the six b1 and three a2 modes in both the ground state (eA1) and the electronically excited first singlet state (eB2). The procedure of the extraction of these modes on the basis of observed sequences, cross-sequences, and overtones has especially been elaborated. Strong Fermi interaction has been observed between the vibrational level ν6b and combination level ν16a + ν16b in eB2 state. The uniqueness of the assignments of the modes has been critically discussed.  相似文献   
156.
The upper bound on the minimum number of modes for a qualitatively correct Galerkin approximation to the two-dimensionl Bénard convection is discussed. For that case and the ext case, selection rules are introduced insuring that the approximation satisfies the same energy balance conditions as the exact solution. These rules together with the proof of boundedness of the Galerkin approximation help establish bounds on the amplitudes of the modes. Finally, results of some mathematical (numerical) experiments carried out in this context are discussed.  相似文献   
157.
The space charge wave of an electron beam excited by the reactive medium instability in a uniform magnetic field region is observed to propagate into the region of increasing magnetic field. When the wave passes through the cyclotron resonance region, it suffers heavy cyclotron damping.  相似文献   
158.
Millimeter-wave characterization of a heterodyne receiver using (2 m2) Nb/Al-Ox/Nb Superconducting-Insulator-Superconducting (SIS) junctions arrays is reported. The fabrication of the Nb/Al-Ox/Nb SIS junction arrays as a heterodyne mixer is described. The leakage current of these junctions is below 2A at 4.2K and unmeasurable at 2.5K. The receiver gave a noise temperature Double Side Band (DSB) between 63K and 187K over the frequency range 80 to 115 GHz at the first conversion peak. The results are comparable to those obtained with SIS receivers using well researched lead junctions. Contrary to the lead junctions, our mixer using all Nb junctions have proven remarkably stable with respect to thermal cycling, characteristics which are required for space applications. To our knowledge, this is the most reliable low noise receiver operating in this frequency range.  相似文献   
159.
The dynamics of optical filaments in broad aperture semiconductor lasers was studied. We use the model where one longitudinal mode is taken into account. The spectrum and the instabilities of lateral modes joined with the above mentioned longitudinal mode were investigated. The structures arise due to instability of various number of lateral modes. On the background of these modes we found a new type of modulation with a frequency depending on the laser aperture width. This frequency is smaller than the electron-photon resonance one. The existence of the modulation was confirmed by experimental investigations of broad aperture laser noise spectra.  相似文献   
160.
A series of measurements on the high pressure (up to 18 bar) coaxial e-beam pumped Ar/Xe laser has been made at high power loading (up to 25 MW/cm~2) for various Xe mole fraction in Ar. We found that the optimum laser gas composition in our system was 0.4% Xe in Ar which was independent of the total gas pressure. At the optimum gas composition the output energy increased with increasing total gas pressure up to 16 bar, but the intrinsic efficiency reached a maximum at the total gas pressure of 8 bar. It was also found that at the optimum power deposition for both the 2.63μm and 2.65μm transitions the ratio of the integrated optical energy to that of the 1.73μm transition had a minimum in most cases at the optimum gas mixture for various gas pressures. This ratio increased with increasing gas pressure. The experimental results suggested that besides the 2-body Xe quenching at high Xe fraction and electron collision mixing at high power depositions the heavy particle quenching from Ar at high gas press  相似文献   
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