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1.
Soft tissue infections are among the rare manifestations of extra intestinal salmonellosis and occur more frequently in immunocompromised patients. Herein we report a case of a 51-year-old white male with type II. diabetes mellitus, diagnosed with supraclavicular abscess caused by Salmonella enteritidis. The patient denied any gastrointestinal symptoms, and stool cultures were negative. After incision, drainage, and administration of intravenous ampicillin (4 x 1.5 g/day for two weeks) the patient recovered completely. To our knowledge, this is the first reported case of cervical soft tissue abscess caused by Salmonella enteritidis without preceding gastrointestinal symptoms. We feel that the presence of diabetes was a risk factor for developing the infection.  相似文献   
2.
In the analysis of farinographic curves, it has been determined that the farinogram area is a very reliable indicator of the quality of wheat flour, if it has been measured 12 min from the achievement of the maximum. In such a way, the dough development time, which can considerably influence the size of the farinographic curve, if it has been measured 15 min after the farinograph has been set in motion, has been eliminated. Quantitative relations between one of the most important characteristics of the farinogram – the farinogram area, and the determined dough characteristics related to dough quality which can be registrated by means of the extensogram, have been determined: , where Afar = farinogram area measured 12 min from the achievement of the maximum, E = dough extensibility, A = area of the extensogram, k′ = represents the farinographic area when the ratio unit value is $ \frac{{{\rm E}^2 }}{{\rm A}}$, k?′ = 4.18 and standard deviation s = 0.214. This determined relation gives a new approach to the farinographic curve interpretation and stresses the new importance of the farinograph as an instrument for physical testing of wheat flour quality.  相似文献   
3.
Lung slices from rats fed a fat-free diet supplemented with safflower oil (control) or tripalmitoyl-glycerol (essential fatty acid [EFA]-deficient) were incubated with [14C] acetate, [14C] palmitate, or [14C] stearate. Of the14C recovered in phospholipids after incubation with [14C] acetate, more than 87% was in 16-carbon fatty acids. Desaturation, as assayed by the percentage of radioactivity in monoenoates in phospholipid fatty acids, was generally double in EFA-deficient slices compared to control slices, regardless of substrate. Desaturation was significantly greater in slices incubated with acetate or octanoate compared to palmitate, indicating that endogenously synthesized palmitate was desaturated more actively than that derived from an exogenous source. Presented in part to the American Physiological Society, Toronto, Canada, October 1980, and published in abstract form inPhysiologist (1980) 23, 135.  相似文献   
4.
In this paper, it is shown in which kind the pressure difference across the free surface has to be chosen to obtain a stable convex static meniscus with a prescribed size in the case of a Ge1−XSiX single crystal ribbon growth by E.F.G. technique. The dependence of the pressure difference on the composition X is analyzed. The same tools as for a Ge or Si single crystal ribbon growth are used. The results can be useful in a future experiment planning or manufacturing technology design.  相似文献   
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6.
An integrated scheme is developed based on the controlled Poisson Voronoi tessellation (CPVT) model to generate the polycrystalline grain structure for micromechanics simulations. The proposed model of CPVT involves a single control parameter that is used to produce the grain structure with regularity control, by which the yielded tessellation varies from the purely random Voronoi tessellation to the regular hexagonal tessellation. The system extends the standard CPVT model by the addition of two features: a one-parameter gamma distribution and a mapping from a set of quantitative metallographic measurements to the distribution parameter. Based on this scheme, a grain structure can be constructed such that the virtual tessellation is statistically equivalent to the expected grain size distribution. To validate the modules that utilise the physical parameters that dictate the regularity, a series of theoretical investigations is performed. Efforts are devoted to proving the uniqueness of the mapping from the physical parameters to the distribution parameter and the regularity parameter. An efficient numerical algorithm is provided to facilitate the mapping solution process. A software system (VGRAIN) is developed implementing the proposed CPVT model to generate the grain structure for crystal plasticity finite element (CPFE) analysis. To demonstrate the proposed scheme and the VGRAIN system, a plane strain CPFE analysis is conducted. Two microstructures are generated with different regularities, and the deformation under uniaxial tension is simulated.  相似文献   
7.
Our goal is the oscillation susceptibility analysis in the framework of a nonlinear mathematical model in the so-called ADMIRE or Aero Data Model in a Research Environment. First, we analyze the oscillation susceptibility along the path of the longitudinal flight equilibriums when the flight control system (FCS) is decoupled. After that, a similar analysis is undertaken in the case when the FCS is coupled. For decoupled FCS, it is shown that on the path of the longitudinal flight equilibriums there exists a saddle-node where stability is lost and fold bifurcation occurs. Maneuvers are simulated showing the effect of an instantaneous change of the elevator angle, and the evolution of the unstable equilibriums (due to the maneuvers) to the corresponding exponentially stable equilibriums. It is shown numerically that at the saddle-node oscillations occur when the elevator angle is less than the critical value and the start is from the saddle-node. More precisely, it is shown that if the plane state parameters coincide with the saddle-node coordinates and the elevator angle is changed instantaneously from the critical value to a value which is less than this value, then two of the state parameters (α,q) begin to oscillate with the same period and the third parameter (θ) increases, tending to infinity. Thus, the orbit of the system evolves spiraling. It is shown also, that if the elevator angle is reset, the plane returns to a stable equilibrium. Therefore, a soft or no catastrophic stability loss takes place. When the FCS is coupled, the plane for every value of the amplification factor has a unique equilibrium which is exponentially stable and attracts all the equilibriums which exist in decoupled case. In this case, there are no bifurcation points on the equilibrium path. The dependence of the equilibrium and of the relaxation period on the amplification factor value is found numerically. Finally, it is concluded that when the FCS is decoupled, then along the path of the longitudinal equilibriums oscillations can occur, but when the FCS is coupled and the pilot can modify (instantaneously) only the amplifier factor value, then the vehicle, defined by the considered numerical data, is not anymore susceptible to oscillation.  相似文献   
8.
This paper introduces a method for the production of bi-metal gears using the forging technique. To study the process, model materials of copper (tooth ring material) and lead (core material), were used for both experimentation and simulation. Firstly, experimental setup and test procedures are introduced and the bi-metal gears are forged with different thicknesses of the outer ring material. A simplified FE model is established based on the symmetry of a gear forging process, which enables the 3D FE analysis to be carried out in an efficient manner. The material flow and thickness distribution of the experimentally forged bi-metal gears are analysed and compared with FE predictions. The effect of friction on the axial lock caused by the material flow of the forged gears is also studied. Finally, simulations of different combinations of the inner core and outer ring materials, specifically steel (ring material), copper (ring and core material) and lead (core material) are performed. The numerical and experimental data showed that: thin rings can deform excessively, affecting the structure of the gear; and that both tooling friction and flow stress can significantly affect the relative material flow between the core and the ring.  相似文献   
9.
The photocatalytic mineralization of oxalic acid over SiO2-based materials was investigated in the 200–800 nm range. The photocatalytic activity was found to be strongly related to the morphology of SiO2 materials. The simple as well as the Pt-modified SiO2 particles having a predominant spherical shape exhibited null photocatalytic activity. In contrast, the tubular shaped SiO2 particles revealed an interesting photocatalytic activity, the rate of CO2 evolvement being 45 µmol g cat ?1  h?1. The initial activity was significantly enhanced (428 µmol CO2 g cat ?1  h?1) by platinum photodeposition on the outer and inner surface of tubular SiO2. The catalytic materials were characterized by TEM, UV–VIS and XPS to obtain rational explanations for the phocatalytic activity that was noticed. The experiments revealed that SiO2 tubes behave as efficient photooxidation microreactors. The morphology-dependent photocatalysis can be an efficient tool in future for the abatement of pollutants in liquid phase.  相似文献   
10.
Supercritical carbon dioxide (SC-CO2) extraction on a laboratory-scale, was applied to produce oleoresin from dried onion (Allium cepa L). The goal of this work was to determine the optimal conditions of extraction for producing oleoresin with the highest yield and the best quality. A polynomial model was developed on the data. The square of correlation coefficient was R2=0·9022 (at P⩽0·05). The statistical analysis showed that the extraction pressure, temperature, and time have significant influence on the yield of the oleoresin. Increasing these parameters resulted in an increase in the yield. Maximum yield was obtained when the extraction pressure and temperature were above 350 bar and 57°C, respectively. At the lowest pressure (150 bar) applied the highest concentration of sulphur was produced in the oleoresin. The concentration of sulphur increased as a function of temperature when the pressure was maintained at 300 and 400 bar. The composition of volatile compounds of oleoresin differed from that of distilled onion oil. © 1998 SCI.  相似文献   
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