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991.
生物油的特性、提质及应用   总被引:1,自引:0,他引:1  
张丽丽 《安徽化工》2011,37(2):5-7,12
生物油是一种由生物质直接转化为液体燃料的新型可再生能源,具有产量大、可储存和碳循环等优点。综述了国内外生物油的物性特点、提质以及应用等研究进展。结果表明,生物油作为化石燃料的替代燃油存在很大优势,但其热值低、腐蚀性强等缺陷仍需进一步改进。  相似文献   
992.
Shell煤气化工艺特点及存在问题   总被引:3,自引:0,他引:3  
介绍了Shell煤气化工艺的特点,并提出该工艺目前运行时面临的问题。  相似文献   
993.
刘颖  崔彬  林文姬  孙鹤天 《洁净煤技术》2011,17(1):119-121,107
从母岩特征、气候特征、沉积环境等方面分析了锦25区块沙一段沉积背景。依据大量地质资料,叙述了辫状河三角洲碎屑岩特征、粒度、沉积构造、泥岩特征等沉积特征,总结研究区辫状河三角洲的生储盖特征。  相似文献   
994.
石灰浆液雾化喷嘴是烟气脱硫系统的关键设备.对一种简式旋流石灰浆液雾化喷嘴的雾化特性进行了实验研究,分析了雾化压力、浆液浓度对雾化角、雾滴粒径分布的影响规律.实验表明:浓度增加,雾化角减小;而雾化压力对雾化角影响较小,雾化角在60°~70°之间;随着雾化压力的增大,雾化流量也增大;当雾化压力大于0.09 Mpa临界雾化压...  相似文献   
995.
Design, Development, fabrication and investigation of the IV characteristics of the DSSC based on interconnected 15 nm SnO2 nanoparticles covered with a nano-scale thin layer of CaCO3 are described. The presence of CaCO3 has been confirmed by its characteristic XRD pattern and EDX plots. The thickness of the protective layer can be conveniently controlled by the molar ratio of SnO2:CaCO3 used in the preparation of the thin film and the optimum conditions for best performance of the DSSC are presented together with possible explanations for the variations observed when the molar ratio is changed. An optimum light-to-electricity conversion efficiency of 5.4% in the presence of a layer of CaCO3 has been obtained which is 3.2 times enhancement over the cell prepared without CaCO3. The characterization of the surface using different techniques is explained.  相似文献   
996.
To understand more about the sulfur composite prepared by sulfurized polyacrylonitrile at 300 °C, electrochemical impedance spectroscopy (EIS) is employed to investigate the electrochemical properties of the sulfur composite cathode during discharge process. The impact of discharge depth on the performance of sulfur composite materials is investigated. The electrolyte solution resistance, the charge transfer resistance and the interface impedance are evaluated from the EIS analysis. The charge transfer resistance and the interface impedance increase during delithiation and decrease during lithiation, while the concentration of Li+ in the composite decreases and increases, respectively. Meanwhile the electrolyte solution resistance is likely to keep stable. The interface resistance and charge transfer resistance of the sulfur composite cathode decrease rapidly after initial lithiation, while Li+ diffusion coefficient and exchange current density increase rapidly. After the initial lithiation, they are likely to keep stable. This study reveals more characteristics of the sulfur composite, which is considered to be a promising candidate for large capacity cathode material.  相似文献   
997.
A long unresolved problem in two-phase flow is that the inviscid form of a standard model is not hyperbolic, making initial-value problems based on the model ill-posed. In this paper we show that the model becomes hyperbolic when the buoyant force term in the model is modified to include the effect of relative motion between the phases. We also show that the new model gives physically realistic solutions for minimum fluidization, expansion of a tapered fluidized bed, and the flow of a neutrally buoyant mixture through a nozzle and compare the solutions with those of the standard model and an alternative model.  相似文献   
998.
采用熔盐法制备了YAG:Ce3+黄色荧光粉,并与传统的固相-助熔剂法制备的相应粉体在晶体的形貌和外表特征及对发光性能的影响作了比较和分析。研究结果表明,熔盐法能有效改善荧光粉晶体的形貌和外表特征,制备出的荧光粉表面更光滑,分布更均匀,颗粒趋于近球形生长。  相似文献   
999.
PVF (polyvinyl formal) porous materials have attractive properties, such as noise attenuation, good structural integrity, thermal and chemical stability, high permeability and large specific surface area, for many flow‐through applications. Several characteristics of the porous material will have an impact on the permeability, and gas flow and diffusion. However, the shape and the design of the device may also have significant impact on the gas flow. A porous media model and Darcy‐Forchheimer principle were used as the basic theoretical frame. The unified governing equations were used to describe the compressible flow in and out of a PVF porous tube. A robust NND numerical scheme was used to discretize the equations and the TDBC (time‐dependent boundary conditions) were used to treat the nonreflective boundaries. Numerical simulations of an interior and exterior flow field of a PVF porous tube were completed. The detailed flow characteristics of the inner and outer flow fields of the tube were obtained. The velocity distribution of the outside of the tube compare very well with the experimental data.  相似文献   
1000.
The effect of carbon black fillers viz. semireinforcing furnace (SRF), high abrasion furnace (HAF) and intermediate super abrasion furnace (ISAF) carbon blacks on the cure, swelling and mechanical properties of 70/30 EPDM/NBR blend have been investigated. The maximum torque values have been found to be increased with increase in filler loading. Filledsystems have been found to exhibit a reduced solvent uptake tendency compared to the unfilled sample. Blends loaded with ISAF exhibited the lowest toluene uptake among the carbon black filled systems due to the better filler reinforcement. A more uniform morphology has been observed for ISAF‐filled samples compared to the other filler loaded systems. The improvement in the mechanical properties has been observed to be the highest for ISAF‐filled samples followed by HAF and SRF filled systems. This has been attributed to the smaller particle size of ISAF black. The experimental results of mechanical testing have been compared with various theoretical models. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
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