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Iranian Polymer Journal - The addition of methacrylate-functional polyhedral oligomeric silsesquioxane (MA-POSS) nanoparticles to styrene-butadiene rubber (SBR) composites was evaluated in terms of...  相似文献   
3.
Journal of Signal Processing Systems - Segmentation of thigh tissues (muscle, fat, inter-muscular adipose tissue (IMAT), bone, and bone marrow) from magnetic resonance imaging (MRI) scans is useful...  相似文献   
4.
Submicron iron particles were obtained by the reduction of co-precipitated superparamagnetic iron oxide nanoparticles under hydrogen atmosphere. The reduction was carried out at the temperatures ranging from 200 to 1000 °C. The magnetic properties were investigated in accordance with the structural properties. According to the X-ray diffraction patterns, the increase of crystallization was followed by the conversion from iron oxide to iron and also the particle size increased as the reduction temperature increased. Morphology observed by transmission electron microscope showed that the particles were individually seen at low temperatures; however, they stacked together and became larger at high temperatures. Magnetic measurements with a vibrating sample magnetometer disclosed that the saturation magnetization steadily increased with increasing temperature and almost stabilized at 800 °C. Highest saturation magnetization obtained by the reduction process is ~211 emu/g, which is close to that of bulk iron. It is disclosed that, at all temperatures, saturation magnetizations obtained from magnetic measurements were found to be compatible with the structural changes caused by reduction temperature.  相似文献   
5.
The aim of this study was to integrate multi omics data to characterize underlying functional pathways and candidate genes for drip loss in pigs. The consideration of different omics levels allows elucidating the black box of phenotype expression. Metabolite and protein profiling was applied in Musculus longissimus dorsi samples of 97 Duroc × Pietrain pigs. In total, 126 and 35 annotated metabolites and proteins were quantified, respectively. In addition, all animals were genotyped with the porcine 60 k Illumina beadchip. An enrichment analysis resulted in 10 pathways, amongst others, sphingolipid metabolism and glycolysis/gluconeogenesis, with significant influence on drip loss. Drip loss and 22 metabolic components were analyzed as intermediate phenotypes within a genome-wide association study (GWAS). We detected significantly associated genetic markers and candidate genes for drip loss and for most of the metabolic components. On chromosome 18, a region with promising candidate genes was identified based on SNPs associated with drip loss, the protein “phosphoglycerate mutase 2” and the metabolite glycine. We hypothesize that association studies based on intermediate phenotypes are able to provide comprehensive insights in the genetic variation of genes directly involved in the metabolism of performance traits. In this way, the analyses contribute to identify reliable candidate genes.  相似文献   
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In this study, multiwall carbon nanotube (MCNT)‐supported Pd (Pd/MWCNT) catalysts are prepared by using NaBH4 reduction method. In order to maximize the oxidation and reduction of H2SO4, synthesis conditions (Pd ratio, molar ratio of NaBH4/K2PdCl4, volume of deionized water, and duration of agitation) are optimized by using response surface methodology (RSM). The optimum synthesis conditions are determined as 58.2% of Pd by weight, 154.6 molar ratio of NaBH4 to K2PdCl4, 19.48 mL of deionized water, and 186.16 min of agitation duration. The effect of electrochemical measurement conditions on the oxidation kinetics of Pd/MWCNT is also investigated by RSM. The optimum electrochemical measurement conditions are found as 10 μL of catalyst mixture, 90°C of H2SO4 solution, and 5.5 M H2SO4. The Pd/MWCNT, Pd50Ag50/MWCNT, and Pd65.6Ag33.6Cr0.80/MWCNT catalysts prepared under optimized conditions are characterized by using X‐ray diffraction, transmission electron microscopy, N2 adsorption‐desorption, and inductively coupled plasma mass spectrometry. The crystallite sizes of these catalysts are found as 4.85, 5.66, and 5.26 nm for Pd/MWCNT, Pd50Ag50/MWCNT, and Pd65.6Ag33.6Cr0.80/MWCNT catalysts, respectively. Isotherms of all these catalysts are found to be similar to Type V isotherms with H3 hysteresis loop. The average particle size of Pd50Ag50/MWCNT and Pd65.6Ag33.6Cr0.80/MWCNT catalysts are determined as 5.2 and 9.2 nm, respectively. Electrochemical performance of as‐prepared catalysts is evaluated by using cyclic voltammetry and chronoamperometry. The formic acid electrooxidation (FAEO) activities are found as 18.9, 27.8, and 51.6 mA/cm2 for Pd/MWCNT, Pd50Ag50/MWCNT, and Pd65.6Ag33.6Cr0.80/MWCNT, respectively. Pd65.6Ag33.6Cr0.80/MWCNT shows the highest activity and stability. Optimization of synthesis conditions and electrochemical measurement parameters allow us to obtain very good electrochemical activity and stability for FAEO reaction compared with anode catalysts in the literature.  相似文献   
7.
<正>一座建筑的性能应当如何来衡量?除了通过统治当代建筑舆论的美学、技术以及经济价值来进行描述之外,我们还能够如何来阐释一座建筑,尤其是一座致力于庇护那些渴望展现自己的艺术家的建筑?有人会问成功的表演是如何实现的,表演者是如何进行伪装的、又是如何展现自己的?根据海德格尔的理论,当我们看不到钉子的时候,铁锤的表现才是成功的;钉子本身的出现通常表明出现了问题。  相似文献   
8.
In this paper, a study on the development of a numerical modeling of the detonation of C H N O‐based gaseous explosives is presented. In accordance with the numerical model, a FORTRAN computer code named GasPX has been developed to compute both the detonation point and the detonation properties on the basis of Chapman–Jouguet (C‐J) theory. The determination of the detonation properties in GasPX is performed in chemical equilibrium and steady‐state conditions. GasPX has two improvements over other thermodynamic equilibrium codes, which predict steady‐state detonation properties of gaseous explosives. First, GasPX employs a nonlinear optimization code based on Generalized Reduced Gradient (GRG) algorithm to compute the equilibrium composition of the detonation products. This optimization code provides a higher level of robustness of the solutions and global optimum determination efficiency. Second, GasPX can calculate the solid carbon formation in the products for gaseous explosives with high carbon content. Detonation properties such as detonation pressure, detonation temperature, detonation energy, mole fractions of species at the detonation point, etc. have been calculated by GasPX for many gaseous explosives. The comparison between the results from this study and those of CEA code by NASA and the experimental studies in the literature are in good agreement.  相似文献   
9.
This paper is concerned with the fracture analysis of an agitator shaft of a large vessel and predicting its high cycle fatigue life. The agitator shaft has a circumferential notch around it and is subjected to remote bending and torque created by the mixing operation. The problem is comprised (i) the analyses of the bending force and torque acting on the agitator by using the analytical method, (ii) calculation of stress intensity factors under mode I and III loading conditions by using finite element method and, (iii) fatigue analysis of the agitator shaft failed in service.An agitator model is set up and data obtained from the agitator are processed to make more realistic approximations for bending forces, since they form a base for stress analysis, in which mode I stress intensity factors are evaluated. Mode I stress intensity factors obtained by finite element analysis are compared with the results provided by using the body force method.  相似文献   
10.
The increasing complexity of distribution systems requires general, efficient, and large-scale capable methods. This paper proposes a new technique to find the tap positions of step voltage regulators in multiphase load flow solvers in a direct and efficient manner. This is achieved by applying Newton method to the system of equations obtained by using the concept of augmented matrix formulation and adding the constraint equations. This approach allows employing the regulator equations directly. The regulators are modeled by taking into account the line drop compensator circuit with its settings, i.e., the desired voltage level, bandwidth, and R′ and X′ settings, which represent the scaled impedance parameters of the distribution feeder between the regulator and the load center at which the voltage is controlled. The limits of the regulators such as minimum and maximum tap positions are also accounted for. The proposed technique represents a voltage regulator with transformer equations using an augmented matrix formulation. The mismatch equations are developed using the desired voltage setting in constraint equations with transformation ratio of the transformer being the unknown variable. The Jacobian matrix, which is constructed using the augmented matrix formulation, is expanded to hold the constraint equations of voltage regulators. The proposed new method is tested on a variety of test circuits including the large-scale IEEE 8500 Node Test Feeder, and the minimum number of iterations reported in the literature is achieved as presented in this paper.  相似文献   
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