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1.
The addition of metallic Ir and Pt to a fullerene-forming, atmospheric-pressure plasma reactor was found to influence the generation of carbonaceous products. It was observed that the added metals were efficiently dispersed into the plasma and that their presence increased the yield of fullerenes. The addition of Ir led to a noticeable shift in the fullerene distribution towards C60, whereas the addition of Pt increased the proportion of C60 oxides and decreased the proportion of higher fullerenes. Addition of Ir also caused a reduction of the soot particle size and the formation of a considerable quantity of carbon nanotubes.  相似文献   
2.
We studied the interrelation between the composition, morphology, and helium permeability of the shell of narrow fractions of nonmagnetic nonperforated cenospheres extracted from cenosphere concentrates of fly ash of the sialic type with the use of technological stages of hydrodynamic, magnetic separation, sizing, and aerodynamic classification. For the interval of variation of Al2O3 content from 20 to 38 wt %, the regression equation [SiO2]/[Al2O3] = 5.06 − 0.1[Al2O3] is established, with the correlation coefficient equal to −0.98. It is found that, together with the growth in the concentration of Al2O3 in the indicated interval, the content of the originally mullite phase increases from 1.3 to 42.4 wt %, and this is accompanied by the growth of the helium permeability of the glass-crystalline shell of the cenospheres.  相似文献   
3.
Based in the notions of topological system of S. Vickers and lattice-valued topological space of S.E. Rodabaugh, the paper introduces a generalization of the concepts of state property system of D. Aerts and closure space (used by many authors in the literature), showing that the categories of the new structures are equivalent.  相似文献   
4.
In part III of this series of articles, we present the analysis of transient permeation through two‐layer reactive–passive (RP) film designs, the analysis extension to multilayer structures, and optimized design solutions for multilayer barriers incorporating immobile noncatalytic oxygen scavenger within one of the layers. The reduction of oxygen ingress into a package within a certain timeframe depends on two factors: extension of the scavenger exhaustion time and reduction of the transient transmission rate through the film during that time. The optimal design for the scavenger exhaustion time involves exposure of the reactive layer to the package contents and its protection from high levels of environmental oxygen by the best possible passive barrier layer. The film barrier properties can be further optimized by the selection of the matrix material to place the scavenger in. Reducing the initial transmission rate requires the placement of the scavenger within a layer with the lowest diffusivity of the matrix polymer. When one chooses between two layers with different material transport properties in which to put the scavenger, the optimal solution for the ingress depends on the desired time to provide an improved barrier. The lifetime of the scavenger in the RP film is shortened for design 1, when the diffusivity of the reactive layer is smaller than that of the passive layer, compared to RP design 2, with the layer matrix sequence reversed, but the transient transmission rate is greatly reduced on average for the former. If the desired time to provide a barrier does not exceed the scavenger exhaustion time for RP design 1, the lowest diffusivity material should be used as a matrix for the innermost layer loaded with the scavenger. Otherwise, the highest possible passive barrier should be placed into the film external layer to minimize the total ingress during longer times. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1966–1977, 2006  相似文献   
5.
A large group of prion‐associated proteins was identified in yeast cells using a new approach, comparative analysis of pellet proteins of crude cell lysates in isogenic strains of Saccharomyces cerevisiae differing by their prion composition. Two‐dimensional (2D) electrophoresis followed by MALDI analysis of the pellet proteins of [PSI+] and [psi?] strains after prion elimination by GuHCl and prion transmission by cytoduction permitted identification of ca. 40 proteins whose aggregation state correlated with the change of prion(s) content. Approximately half of these proteins belonged to chaperones and to enzymes of glucose metabolism. Chaperones are known to be involved in prion metabolism and are expected to be present in prion‐containing aggregates, but glucose metabolism enzymes are not predicted to be present. Nevertheless, several recent data suggest that their presence is not incidental. We detected six proteins involved in oxidative stress response and eight in translation. Also notable is a protease. Most of the identified proteins seem to be prion‐associated, but we cannot exclude the possibility that several proteins may propagate as prions. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
6.
Cybernetics and Systems Analysis - Preliminary signal processing methods used to create new tools to examine materials and digital sound recording means are described. It is shown that using...  相似文献   
7.
Journal of Computer and Systems Sciences International - The work is devoted to studying the dynamics of unstable oscillating systems (in the form of an inverted pendulum) controlled by the action...  相似文献   
8.
The critical state model developed nearly 50 years ago by Bean (Phys. Rev. Lett. 8:250, 1962) allows finding analytical solutions for the magnetization of a superconducting slab in a parallel field and for a thin strip in perpendicular field, as well as the transport of AC current by a tape with elliptic or strip-like cross-section. Direct application of these models to the currently available HTSC coated conductor tapes is problematic because of several factors:
  • Dependence of critical current on the magnitude of magnetic field and its orientation
  • Non-uniformity of superconductor properties across the tape width or thickness
  • Magnetism of the substrate
Plausible solution is a numerical model for the process of magnetic flux penetration and associated time evolution of current density distribution. State-of-the-art commercial codes for finite element could cope with this problem. The numerical method based on the relation between the current density and the change of vector potential of magnetic field in two-dimensional geometry is presented and the results obtained for coated conductor tapes are reported. Influence of mesh parameters (density and shape of elements) as well as the thickness of boundary between opposite current densities on the calculated AC loss is analyzed. The recommendations for practical use of simulation method are formulated.  相似文献   
9.
High-calcium fly ash middlings of brown coal of B2 (sub C) rank from the Berezovsky coal mine within the Kansk-Achinsk Basin were studied. The middlings were selectively sampled from the convection pass, the fore-hearth and each of the 4 fields of the electrostatic precipitator at the coal-fired power plant BSDPS-1. The differences of the dispersity, the chemical and mineral-phase composition and the cementing properties of these middlings, as well as the types in the ash classification system were determined. Within the ternary CaO-SiO2-Al2O3 diagram, the equilibrium phases composition of the aluminosilicate constituent of middlings and the pozzolanic capacities of glasses of this system were analyzed and compared with the actual phase composition. It was concluded that the fly ash middlings of the 4 fields of the electrostatic precipitator have the best prospect of utilization as component of cementing materials including portland cement and belite-sulfoaluminate cement.  相似文献   
10.
Improved jitter buffer management algorithms that synchronize the time of the arrival of voice IP packets with their generation time and take into account their order of entry into the codec are suggested. The suggested algorithms provide higher quality of voice communication (especially under strong network loading) in comparison with the known management algorithms for fixed jitter buffers.  相似文献   
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