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1.
Standard documents introducing the notion of uncertainty in measurements into the common practice of assessing the results of chemical analysis are considered and criticized.  相似文献   
2.
The binding energy (b.e.), r.m.s. radius and charge form factor of the4He nucleus are calculated for the Hamada-Johnston potential using the method developed in part I of this study. The single-particle spectrum is derived from that of a harmonic oscillator by means of an overall shiftC and state-dependent shifts h of occupied levels. The's are chosen self-consistently and the dependence of results onC and oscillator frequency is examined. Third-order diagrams in the BG expansion for energy are explicitly calculated (except those belonging to the three-particle cluster) and their importance for getting a weak dependence of the b.e. onC is demonstrated. Dependence on remains rather strong; arguments are given in favour of the choice of that minimizes second-order diagrams. Effects due to the motion of the centre of mass of the nucleus are eliminated by subtracting T CM calculated up to the second order, the usual zero-order approximation of T CM being shown to overestimate the b.e. by 3–5 MeV. The computed b.e. and r.m.s. radius represent about 50% and 110% of experimental values respectively. The form factorF ch(q) was computed for 0q 220 fm–2; the first-order approximation is a good fit to experimental data, while in the second order diagrams appear that worsen the fit forq 2 > >10 fm–2.The author thanks Professor I. Úlehla for stimulating discussions. The help of dr. J.Hoejí, who calculated a part of higher order diagrams, is gratefully acknowledged.  相似文献   
3.
Soft tissue sarcomas (STS) are a rare and highly heterogeneous group of solid tumors, originating from various types of connective tissue. Complete removal of STS by surgery is challenging due to the anatomical location of the tumor, which results in tumor recurrence. Additionally, current polychemotherapeutic regimens are highly toxic with no rational survival benefit. Cold atmospheric plasma (CAP) is a novel technology that has demonstrated immense cancer therapeutic potential. Canady Cold Helios Plasma (CHCP) is a device that sprays CAP along the surgical margins to eradicate residual cancer cells after tumor resection. This preliminary study was conducted in vitro prior to in vivo testing in a humanitarian compassionate use case study and an FDA-approved phase 1 clinical trial (IDE G190165). In this study, the authors evaluate the efficacy of CHCP across multiple STS cell lines. CHCP treatment reduced the viability of four different STS cell lines (i.e., fibrosarcoma, synovial sarcoma, rhabdomyosarcoma, and liposarcoma) in a dose-dependent manner by inhibiting proliferation, disrupting cell cycle, and inducing apoptosis-like cell death.  相似文献   
4.
For a class of piecewise monotone locally noncontracting maps f:X-->X with small "traps" Y( varepsilon ) subset, dbl equals X (diam(Y( varepsilon )) infinity conditional probabilities that f(n+1)x in X\Y( varepsilon ) if x,fx,.,f(nx) in X\Y( varepsilon ) and the point x is chosen at random. Also proven is the convergence of &mgr;( varepsilon ) to smooth f-invariant measures as varepsilon -->0. By means of this construction, the numerical phenomenon of the convergence of histograms of trajectories of maps with marginal singularities to densities of nonfinite smooth invariant measures in the computer modeling was investigated.  相似文献   
5.
Total charge-changing cross sections have been measured for8Li on C and Pb targets, for9Li on C, Al, Cu, Sn and Pb targets, as well as for11Li on C, Sn and Pb targets at about 80 MeV/nucleon. These data are compared to measured total reaction cross sections and Glauber-type calculations using Hartree-Fock density distributions. These comparisons allow to draw conclusions on the proton density distribution of the neutronrich lithium isotopes. The results show that even for the most exotic nucleus11Li the proton distribution is only very weakly influenced by the long tail in the neutron density distribution already established in several experiments.  相似文献   
6.
Following implantation labeling with either 200 or 270 keV Xe+ the sputtering yield of silicon bombarded with 20 keV Xe+ has been determined in situ by means of the backscattering technique (Y = 3.0 ± 0.3 (atoms/ion)). Yield enhancement by up to 60% was observed in cases where the implantation-induced xenon concentrations exceeded the saturation concentration during sputtering. The effect is attributed to (i) an increase in energy deposition at the surface introduced by pronounced xenon loading of the target and (ii) lowering of the surface binding energy. As a consequence the energy dependence of the xenon sputtering yield of silicon is expected to be strongly affected by the energy dependence of the xenon saturation concentration in silicon. Available experimental data support this idea.  相似文献   
7.
The cluster statistics of percolation theory are used to find the distributions of hydraulic conductivity, K, of anisotropic (truncated) random fractal media. Rescaling of variables to transform anisotropic to isotropic media also produces deformations of, for example experimental volumes, and the resulting non-equidimensional shapes may generate interesting size effects on K. Previously, the most likely value of K was obtained by comparing the correlation length from percolation theory with system dimensions, a procedure analogous to those developed for hopping conduction in disordered systems to calculate the longitudinal conductivity of thin films. The result probably explains the frequent tendencies of measurements of K in anisotropic fracture networks and agricultural soils to increase with the scale of measurement, similarly to how the longitudinal conductivity of a thick film would be larger than the corresponding conductivity of a thin film (three- rather than two-dimensional conduction). However, the same procedure applied to the conductivity in the perpendicular direction (analogous to the transverse electrical conductivity of a thin film) shows a diminishing function of spatial scale. Collectively, these ‘scale effects’ disappear if the shape of the experimental volume is selected to maintain the relationships of conduction in the various directions as the scale of the experiment is increased analogously to equidimensional volumes in isotropic media. The increase in K is, thus, merely due to an increase in the dimensionality of conduction from one to three with increasing system size. The paper, thus, provides a solid argument against a common assumption in the porous media communities that the connectivity of highly conducting regions of a medium should increase with increasing scale of measurement.  相似文献   
8.
9.
The nucleus 54Zn has been observed for the first time in an experiment at the SISSI/LISE3 facility of GANIL in the quasifragmentation of a 58Ni beam at 74.5 MeV/nucleon in a (nat)Ni target. The fragments were analyzed by means of the ALPHA-LISE3 separator and implanted in a silicon-strip detector where correlations in space and time between implantation and subsequent decay events allowed us to generate almost background free decay spectra for about 25 different nuclei at the same time. Eight 54Zn implantation events were observed. From the correlated decay events, the half-life of 54Zn is determined to be 3.2(+1.8)(-0.8) ms. Seven of the eight implantations are followed by two-proton emission with a decay energy of 1.48(2) MeV. The decay energy and the partial half-life are compared to model predictions and allow for a test of these two-proton decay models.  相似文献   
10.
The regime of atomization of Si in the presence of Fe-subgroup metals was investigated with the use of a “Saturn” spectrophotometer and a “Graphit-2” electrothermic atomizer. The optimal operating parameters of the atomizer have been determined. It was established that the optimal value of the ashing and the atomization temperatures are, respectively, 900–1000°C and 2400°C, the optimal rate of temperature rise at the stage of atomization is 1400 K/sec, and the appropriate amount of Fe, Co and Ni additions is 1–2 μg. It was established that the formation of gaseous silicides of the Fe-subgroup metals, the dissociation energies of which are lower than the dissociation energies of Si oxides and carbides, increases the sensitivity for determination of Si. To whom correspondences should be addressed. Institute of Single Crystals, National Academy of Sciences of Ukraine, 60, Lenin Ave., Khar'kov, 310001, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 153–157, March–April, 1999.  相似文献   
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