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1.
The energy dependent parameter characterizing the leading particle effect allows to restore the scaling in proton-proton and antiproton-proton multiplicity distributions from Serpukhov until highest available CERN \(S \bar ppS\) collider energies. The identification of theoretical second dispersions with the experimental ones represents one of the basic ingredients in the quantum statistical bosonic approach applied in the present contribution. The KNO scaling at the ISR energies as well as the Worblewski relation for the second dispersions at the \(S \bar ppS\) collider energies arise quite naturally; similar phenomena might appear at higher energies too. Some predictions for 2 and 10 TeV cms energies are specified.  相似文献   
2.
Two crystals with precise parabolic holes were used to demonstrate sagittal beam collimation by means of a diffractive–refractive double‐crystal monochromator. A new approach is introduced and beam collimation is demonstrated. Two Si(333) crystals with an asymmetry angle of α = 15° were prepared and arranged in a dispersive position (+,?,?,+). Based on theoretical calculations, this double‐crystal set‐up should provide tunable beam collimation within an energy range of 6.3–18.8 keV (ΘB = 71–18.4°). An experiment study was performed on BM05 at ESRF. Using 8.97 keV energy, the beam profile at various distances was measured. The experimental results are in good agreement with theoretical predictions. Owing to insufficient harmonic suppression, the collimated (333) beam was overlapped by horizontally diverging (444) and (555) beams.  相似文献   
3.
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The local sensitivity of photo-multiplier photo-cathodes
The influence of the non-uniform distribution of the sensitivity of a photo-multiplier photo-cathode on the spectrum shape of the output pulses from a scintillation detector is studied. Methods of scanning the local sensitivity and determining its distribution function are described. The theory was compared qualitatively with measurement on a slow-neutron detector from a mixture of zinc sulphate and boric acid.
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4.
A direct spectrophotometric method has been developed for the determination of the amount of proteins immobilized on bead cellulose. The method is based on dissolution of conjugates in cadmium tris(ethylenediamine) hydroxide (trivial name, cadoxene) that is optically transparent in the region of the UV spectrum in which proteins absorb. The method developed for the determination of immobilized proteins is simple, rapid, and readily reproducible. The sensitivity of the method is dependent on theA 1cm 1% value of the free protein and on the amount of bound proteinm (mg protein/g carrier). In the terms ofA 1cm 1% ≥25 andm≥120 mg/g, the sensitivity of the mentioned method was comparable with those obtained by amino acids analyses by the ninhydrin reaction, by the modified Lowry reaction, or by radiometric determination. The possibility of substituting the direct spectrophotometric method for amino acid analysis was statistically evaluated; it does not seem to be rejected at the highest level of significance,P≤1%. The differences in paired observations were significant, but nonetheless proportional over the whole range of protein concentrations, making both methods correlable. The absolute accuracy of the direct spectrophotometric method could be influenced by the change ofA 1cm 1% value during solvolysis of the conjugate in cadoxene.  相似文献   
5.
This article gives an overview of uncommon replaceable matrices (gels) for capillary gel electrophoresis. This electrophoretic technique is useful mainly for the separation and analysis of biopolymers-nucleic acids and their fragments, and proteins/peptides. Commonly used gels are not reviewed. Those mentioned and discussed here are gels containing saccharides, newly developed acrylamide-based gels and thermoadjustable viscosity polymers, namely triblock copolymers and grafted polyacrylamide.  相似文献   
6.
Given a variety , we provide an axiomatization of the class of complex algebras of algebras in . can be obtained effectively from the axiomatization of ; in fact, if this axiomatization is recursively enumerable, then is recursive. Received January 18, 2000; accepted in final form December 18, 2000.  相似文献   
7.
To obtain vital spectroscopic data, a specific tandem spectroscopic method consisting of excitation in the DC are separated from the evaporation process was applied. Recently developed tandem spectroscopic methods require a complex evaluation process that can be described by metrological characteristics and from them derived parameters. Evaluation of the novel method optimization process is a part of the application of some chosen, specific, and generally accepted statistical methods. For this purpose, it is suitable to determine parameters of the information theory. It is necessary to compare experimental parameters of the information theory with tolerance parameters representing the values which are supposed to be achieved. To evaluate the given parameters, influence of the concentration range used was taken into account.  相似文献   
8.
Intermittency and multifractality characterizing the presence of dynamical fluctuations are analysed in terms of self-similar processes of Cantor type involving the continuous spectrum of singularities. The fundamental properties of the intermittency slopes q as well as of the strength q and the densityf q , of singularities depending on the order parameterq are established. It is also argued here that the intermittency arisen owing to those self-similar processes leads to such anomalous fractal dimensions and density of singularities which hardly satisfy the assumptions allowing the interpretation of intermittency in terms of thermal as well as non-thermal phase transitions. Four concrete cases are discussed in the present contribution: the e+ e annihilations at s=29 GeV, the ¯pp interactions at s=1800 GeV, the collisions of 200 GeV/ nucleon160 beams with the12C nuclei and the197Au nuclei of energy 1 GeV/ nucleon break up into fragments when interacting with the nuclear emulsion. The corresponding data published so far reveal the fundamental properties following from the aforementioned processes with great accuracy.The author expresses his thanks to M. Markytan, H. Dibon and W. Kittel for fruitful discussions and F. Rimondi for providing him with the preliminary ¯pp data.  相似文献   
9.
The evaporation as a part of the spectrochemical excitation process is a complicated procedure during which different thermo-chemical reactions connected mainly to the formation of carbides are overshot. This one is accelerated namely at the 4000 K on the top of the carrier electrode. The carbide creation markedly affects the evaporation process of single elements of the given matrix and modifies this process. In spite of this it is evident that the intensity of the DC arc has a significant impact on the evaporation of all elements. The evaporation capability of two optical methods, the classical non-controlled direct current (DC) arc spectrography and the PC controlled DC arc optical emission spectrometry, have been compared for the determination of some environmental important elements (Al, Cr, Ni, and V). The experiments were carried out using grating spectrograph PGS-2 and simultaneous multi-channel LECO 750 spectrometer which is connected to a separated evaporation cell and adjusted to the Marinković plasma source. Standardized evaporation curves were designed and the half-time (t50%) values and the total (t100%) evaporation time values were calculated. The basic statistical evaluation was done and the main figures of the merit were calculated.  相似文献   
10.
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