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41.
Supply Chain Operations Reference (SCOR) is a widely employed model for SC performance assessment, regardless its generic nature. This article presents a SCOR-based model for performance measurement in supply chains (SC) and apply it in the context of Brazilian footwear industry. The model has two dimensions: SCOR processes (source, make, deliver and return) and performance standards adapted from original SCOR (cost, quality, delivery and flexibility). This structure delivers a 4 × 4 matrix, with each component assessed under analytical hierarchy process. Using focus groups, SC’s experts weighted each component of the matrix regarding their relevance. Thereafter, SC’s managers indicated respective results. The SC’s overall performance was obtained by adding the performance of all indicators. The model application embraced one focal footwear manufacturer, four suppliers, three distribution channels and a return channel, with 85 indicators assessed. The achieved performance for the whole SC is 75.29%.The main gaps were found in deliver process (12.78 percentual points of difference between relevance and achieved proportions) and in flexibility performance (9.82). Further application is recommended in order to find consolidated results.  相似文献   
42.
The aim of this study was to develop and validate a method for the analysis of fatty acid methyl ester (FAMEs) content in tung biodiesel and blends with soybean biodiesel. The limits of detection (LOD) and quantification (LOQ), linearity, robustness, accuracy and precision were evaluated by using gas chromatography with mass spectrometry detection and impact electron ionization. The analytical curves showed correlation coefficients values higher than 0.99. The LOD and LOQ were 0.78 and 2.5 mg L−1 for all FAMEs, respectively. The values of accuracy were between 86 and 117%, with relative standard deviation lower than 8%. The method was applied to tung biodiesel and tung and soybean biodiesel blends in the following proportions: 15:85, 20:80, 25:75 (%v/v). All of them showed good performance. Since the method was also applied to soybean biodiesel, the efficiency of the method for the analysis of both pure tung biodiesel and blends with different raw materials was confirmed and the robustness of the method was evidenced.  相似文献   
43.
Poly(ethylene terephthalate‐co‐isophthalate) (PETI) prepolymer was submitted to solid state polymerization (SSP) at 184–230°C in a fixed bed reactor, to study the evolution of morphological changes during the process. Short reaction times were selected to investigate crystallization phenomena during nonisothermal (heating) and isothermal SSP phases. More specifically, multiple PETI melting behavior was observed and attributed to secondary crystallization, the rate of which increased significantly with SSP temperature. Reaction time was also found to exert a positive effect on solid‐phase perfection of secondary crystals, leading at each temperature to melting points close to the value of bottle‐grade poly(ethylene terephthalate). Finally, the mass fraction crystallinity of the SSP grades was found to comply with the crystal morphology encountered. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
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A short-term test (time interval < 24 h) is proposed to evaluate the concentration of organic matter from industrial effluents for the production of hydrogen. Organic substrates selected were: protein effluent from a soybean processing plant; glycerol, from the production of biodiesel; Tebuconazole, a fungicide; and glucose, used as a reference substrate. Volatile fatty acids (VFA) and the degree of acidification of each substrate are also determined. After glucose (average hydrogen release of 24.8 mL g COD−1), protein effluent provided the highest hydrogen yield (1.74 mL g COD−1). Acetic and butyric acids presented the highest VFA concentrations. Fermentation of Tebuconazole presented the highest degree of acidification. Some considerations are made about the biological processes involved in hydrogen production.  相似文献   
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In glass-ceramics (GCs), on cooling from the crystallization temperature, internal residual stresses are generated due to the difference between the thermal expansion coefficient (TEC) of the crystal phase(s) and the residual glass. These stresses could degrade or promote their mechanical properties. In this work, we varied the magnitude of the residual stresses in lithium silicate GCs by designing their microstructures. The level of internal stresses was measured using (Synchrotron) X-ray diffraction. The effects of anisotropy of thermal expansion, crystal shape, and intensity of the residual stresses were analyzed and compared using theoretical models. We extended the Hsueh-Becher model to include the thermal expansion anisotropy of the orthorhombic lithium disilicate (LS2) crystals. We found that the average residual stresses within the LS2 crystals are compressive or null (−100 to ~0) and highly anisotropic. Most importantly, within the limits of this study, we found no evidence for the influence of (compressive or null) residual stresses on the fracture toughness of the studied GCs. Within the crystal size range from 1 to 5 μm, a highly crystallized volume fraction coupled to relatively large crystals (5 μm) of high elastic modulus improved the glass-ceramic fracture toughness. This result can guide the microstructural design of novel tough GCs.  相似文献   
48.
Carbon-alumina coatings on stainless steel were prepared by a sol-gel route. The dispersion of the commercial graphite flakes by an ultrasonic bath, an ultrasonic probe and a high-shear mixer, produce thinner flakes, few-layered-graphene and bi-layer-graphene (BLG), respectively. The coatings were examined by optical and electron microscopy, interferential rugosimetry, optical profilometry and Raman spectroscopy. The friction coefficient against a steel ball is decreased by a factor of 5–7 and the wear volume is reduced by a factor of 6–38 compared to a pure alumina coating. The best results correspond to the sample prepared using the high-shear mixer. Delamination of the graphite flakes into BLG during the friction test provides the system with debris suitable for tribofilm building up and lubrication but it is better to already have carbon dispersed as BLG in the coating before the test, notably because the carbon surface area available is much higher.  相似文献   
49.
In this study, raw cow milk containing somatic cells counts (SCC) at mean levels of 39 000 cells mL?1 (low), 349 000 cells mL?1 (intermediate) and 1 297 000 cells mL?1 (high) was used for the production of pasteurised cream. Physicochemical (pH, fat and fatty acid profile) and microbiological analyses (mesophilic and psychrotrophs) were performed in the obtained creams during 30 days of refrigerated storage at 5 °C ± 2. No interactions (P > 0.05) were found between SCC, storage time and the physicochemical and microbiological variables studied. Fatty acid profile was similar among the SCC creams, except for oleic acid (C18:1), which decreased (< 0.05) in intermediate and high SCC creams. Considering the technological aspect, our findings suggest that milk cream manufacture can be an interesting option for the use of high SCC milk.  相似文献   
50.
Chia seeds are a promising raw material for the development of biodegradable and edible polymers due to their composition and properties. This study aimed to evaluate the effects of drying process of chia mucilage (oven and freeze-drying) and the incorporation of chia oil in films for food packaging. The films were formed by casting using chia mucilage and glycerol. The polymers developed were evaluated by physicochemical properties, microstructure, thermal properties, and biodegradation. The drying process of mucilage and oil incorporation in films affected mainly mechanical and color properties. Freeze-dried mucilage resulted in superior mechanical performance. Differences were caused by the effect of drying process in the molecular structure of chia mucilage and the incorporation of oil among the polymer chains. Chia mucilage films were completely soluble in water and biodegraded in a short time in soil. These films are promising biodegradable polymers for the development of eco-friendly food packaging and edible sachets for small pre-measured portions, preventing environment pollution and facilitating product consumption.  相似文献   
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