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11.
Abstract

Scrap tire derived oils were upgraded over metal-loaded activated carbon catalysts and commercial catalyst at different operating conditions. Activated carbon support was prepared from the pyrolytic carbon black from pyrolysis of scrap tires. Activated carbon catalysts contained the metal pairs of Co-Ni, Co-Mo, and Ni-Mo. All metal-loaded activated carbon catalysts showed similar catalytic activity for upgrading process at 350°C under hydrogen pressure of 7 MPa. However, Ni-Mo/Ac showed good catalytic activity. Liquid fuels from upgrading oils over Ni-Mo/Ac and commercial catalyst containing 45–55% of naphtha fraction, 20–25% of kerosene fraction was obtained 350°C under hydrogen pressure of 7 MPa.  相似文献   
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The effects of the annealing temperature on structural properties and the phase transformation of a Cu–14.1Al–3.9Ni (mass %) shape memory alloy (SMA) have been investigated. The annealing process was carried out at temperatures in the range of $700\,^{\circ }{\mathrm{C}}$ 700 ° C to $850\,^{\circ }{\mathrm{C}}$ 850 ° C . The structural changes of the as-quenched and annealed samples were studied by optical microscope and X-ray diffraction measurements. The evolution of the transformation temperatures was studied by differential scanning calorimetry with different heating and cooling rates. The activation energy and thermodynamic parameters of the samples were determined. It was found that the heat treatment has an effect on the characteristic transformation temperatures and on thermodynamic parameters such as enthalpy, entropy, and activation energy. The crystallite size of the as-quenched and annealed samples were determined. Vickers hardness measurements of the as-quenched and annealed samples were also carried out. It is evaluated that the transformation parameters of a CuAlNi SMA can be controlled by heat treatment.  相似文献   
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This article introduces a new mathematical model that predicts the pressure drop in a tangential inlet cyclone. The model calculates the pressure drop from the frictional losses in the cyclone body, using a wall friction coefficient based on the surface roughness and Reynolds number. The entrance and exit losses are also included in the model by defining new geometrical parameters. The pressure drop coefficient is obtained as a function of cyclone dimensions and operating conditions. The model is validated by studying 12 different cyclones presented in the literature. Comparison of the model results with predictions and measurements published in the literature show that the new model predicts the experimental results quite well for a wide range of operating conditions covering a flow rate of 0.3–220 l/s and a temperature range of 293–1200°K, in different cyclones. The pressure drop coefficient is also examined in view of the outlet pipe diameter, friction coefficient, surface roughness, and Reynolds number.  相似文献   
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An iron-based oxygen absorber (ABSO2RB®) activated by moisture was incorporated into a retort laminate and used to package chicken pesto with noodles. The effect of packaging material (regular MRE and oxygen-absorbing pouches) and reformulation with olive oil on the quality and shelf life of the entrée were investigated. Physical properties (color, texture, moisture, water activity), chemical properties (pH, TBARS), and microbiological quality (Total aerobic, coliforms, Escherichia coli, Yeast and Molds, Anaerobic plate counts) were measured in triplicates in an accelerated shelf-life study for 6 months at 37.8 °C. Samples stored at 26.7 °C for 12 months served as calibrated controls. Consumer and trained panel tests were carried out using a 9-point hedonic scale. The ABSO2RB® pouches performed well in terms of seal integrity and strength and limited the formation of rancid fatty acids in olive oil throughout the shelf-life study. Soybean formulations in ABSO2RB® pouches had the lowest (p < 0.05) Thiobarbituric Acid Reactive Substances (TBARS) value. Consumer and trained panelists accepted the olive oil formulations, in both packages. Results from this study will help MRE developers to expand the number of items using healthier oils. If future considerations to replace MRE packaging are needed, the ABSO2RB® film will be a suitable alternative.  相似文献   
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In this study, a series of shape-stabilized phase-change materials (PCMs) of camphene/stearic acid (CS) were prepared and their thermal properties were measured by differential scanning calorimetry. The results indicated that the mixture consisting of 60 mass% camphene and 40 mass% stearic acid is the most favorable as a PCM, in terms of the phase-change temperature and latent heat. Thereafter, the CS was absorbed in fly ash, pyroclastic, barite, and marble powder, which acts as a supporting material, to prepare four kinds of composite-based PCMs. DSC, FT-IR, and scanning electron microscopy measurements were made to investigate the structures and properties of the PCMs. DSC results showed that the latent heats of melting and freezing of the composite PCMs were sharply decreased. Morphology and structural characterization revealed that, in form-stable PCMs, the dispersion of the supporting materials in the camphene/stearic acid matrix is homogeneous and there is no chemical interaction between the CS and composites. The composite PCMs showed excellent thermal stabilities and reliabilities, when their phase-change temperatures were concerned. These indicate that the prepared composite-based PCMs are suitable for thermal energy storage because of their applicable temperature range, thermal reliability, and chemical stability.  相似文献   
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In this article, for the first time in the literature effects of phenylene diisocyanate (PDI)‐based compatibilizer on the physical and chemical properties of citric acid (CA) modified thermoplastic starch (TPS)/poly(lactic acid) (PLA) blends were investigated with respect to PDI and CA content and blend composition. The blends were prepared by melt compounding in a laboratory microcompounder. Fourier transformation infrared spectroscopy results showed that CA interacted with starch and PDI interacted by both starch and PLA through the hydroxyl groups. It was revealed from SEM micrographs that combinatorial usage of CA and PDI resulted in an improved, finer distribution of TPS in PLA matrix. This improvement affected the mechanical properties of blend, especially the toughness related properties such as impact strength and elongation at break. The thermal properties such as Tg and Tm revealed from differential scanning calorimeter analysis were in line with the morphological structure of the blends by suggesting the compatibilization phenomena in the presence of PDI and CA together. Thermogravimetric analysis showed that compatibilization of two phases improved the thermal stability of the blends. As a general conclusion, the combinatorial usage of PDI and CA can be utilized to obtain tougher PLA/TPS blends‐based materials to overcome the brittleness problem. POLYM. ENG. SCI., 53:2183–2193, 2013. © 2013 Society of Plastics Engineers  相似文献   
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A method was developed for protective coating of steel and glass surfaces with poly(methylmethacrylate) (PMMA). In this method, first, a primer coating was formed on the flat surfaces using self-curable polyester, poly(2-hydoxypropyl maleate) (Polymer-1). The polyester was applied onto polished surfaces and heated at 180 °C for 15–120 min to obtain transparent and crosslinked primer layer without using additional crosslinker.  相似文献   
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