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981.
982.
Acrylate and methacrylate monomers were obtained by reacting vernonia oil, a naturally epoxidized oil, with acrylic or methacrylic acid. The highest conversion (85–98%) of epoxy groups was obtained when the reaction was performed with an excess of the carboxylic acid at 100–120°C. The acrylate and methacrylate monomers of vernonia oil were characterized by IR and NMR spectroscopy. These monomers were then cured by sunlight in the presence of benzophenone to produce transparent films. In addition, interpenetrating polymer neworks (IPNs) were prepared in a two‐step technique from the sunlight‐cured methacrylate of vernonia oil, as the elastomeric component, in combination with a cured epoxy resin (a bisphenol A–type resin). Dynamic mechanical analysis showed good compatibility between the networks of the two cured polymers. An IPN with a 1 : 1 composition of the two polymer components exhibited the properties of a reinforced elastomer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3835–3843, 2004 相似文献
983.
984.
欧阳成卓 《网络安全技术与应用》2014,(10):203-204
随着我国科学技术水平和社会经济实力的不断提高,现如今的油库管理应该做到现代化、信息化.在油库管理的信息化建设中,计算机及其系统起到了至关重要的作用.本文介绍了油库管理信息系统的设计原则与具体内容,并详述了计算机系统是如何在油库的信息化管理中应用的. 相似文献
985.
球(管)磨机增效的途径有二:一是从粉磨机理出发,利用磨机本体相关零部件的不同功能对磨机结构进行科学的设计与改造;二是对粉磨系统进行优化。包括对入磨物料的科学处理,采用适宜的工艺流程及辅机设备等。 相似文献
986.
A three‐dimensional oil‐water turbulent flow and oil separation process in a double‐cone liquid‐liquid hydrocyclone (LLHC) is numerically simulated using FLUENT software. The Euler‐Euler approach and Reynolds‐stress model are combined and adopted in this simulation to handle the challenging situation of anisotropic turbulent two‐phase flow with a higher volumetric ratio (over 10%) in the dispersed phase. It is visualized well in the simulation how separation, aggregation and shift of oil and water proceed in the LLHC. The oil separation efficiency is determined based on flow field and phase concentration distribution. The simulation is verified by comparing predicted and measured separation efficiency in the LLHC. 相似文献
987.
Mehdi Qasim Jinan Al‐Dabbagh Naser Mahmoud Ahmed V.G. Chigrinov Gurumurthy Hegde 《Journal of the Society for Information Display》2014,22(4):187-190
Indium tin oxide‐coated thin films (200 nm) are deposited on glass substrates by using R.f. sputtering technique. Here, we investigate the influence of new technique of treatment, which is called as “oil thermal annealing” on the nano‐structured indium tin oxide thin films at fixed temperature (150 °C) which improves adhesion strength, electrical conductivity and optical properties (transmittance) of the films. Oil thermal annealing is used to reduce inherent defects that may be introduced during the prepared thin film and cooling processes. Proposed technique is highly suitable for liquid crystal displays, solar cells and organic light emitting diodes, and many other display‐related applications. 相似文献
988.
Iván Jachmanián Lucía Margenat Ana I. Torres Maria A. Grompone 《Journal of the American Oil Chemists' Society》2007,84(6):597-601
The solubility of different ethyl esters derivatized from hake liver oil in supercritical carbon dioxide was studied. A selectivity
factor was used to determine optimal conditions to fractionate the ethyl ester mixture. A strong influence of solvent pressure
and temperature was observed within 8.63–18.04 MPa and 40–70 °C. The lowest total solubility of the ethyl ester mixture was
obtained when using supercritical carbon dioxide at the lowest density (the lowest pressure and the highest temperatures value
tested). The highest discrimination against long-chain polyunsaturated fatty acids (e.g. EPA and DHA) was also obtained at
these above conditions. Conversely, higher solubility and lower selectivity were obtained when solvent density increased.
Considering this inverse correlation between selectivity and solubility, a single-step batch-fractionation process was designed
to increase the 22:6 ethyl ester content from an initial value of 17.5% in the starting material to 55% in the final extract. 相似文献
989.
Light cycle oil (LCO), a by-product of the fluid catalytic cracking (FCC) process in a petroleum refinery, can be used as a blendstock for the production of diesel and jet fuels. Regulatory and operational issues result in need for new and more active catalysts for the deep hydrodesulfurization (HDS) of diesel feedstocks, such as LCO. This paper reports the activity of a mesoporous molecular sieve MCM-41-supported Co-Mo catalyst in comparison to a commercial γ-alumina (Al2O3)-supported Co-Mo catalyst for the desulfurization of a LCO with a sulfur content of 2.19 wt.%. The HDS of dibenzothiophene, 4-methyldibenzothiophene, and 4,6-dimethyldibenzothiophene—polyaromatic sulfur compounds present in LCO—and their relative reactivities in terms of conversion were examined as a function of time on stream in a fixed-bed flow reactor. The MCM-41-supported catalyst demonstrates consistently higher activity for the HDS of the refractory dibenzothiophenic sulfur compounds, particularly 4,6-dimethyldibenzothiophene. The presence of a large concentration of aromatics in LCO appears to inhibit the HDS of the substituted dibenzothiophenes. 相似文献
990.