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991.
介绍了石化集团原油资源现状,分析了原油资源配置过程中存在的主要问题,提出了资源优化配置的原则与基本思路,及实施原油资源优化配置的配套措施和建议。 相似文献
992.
993.
Xiangming He Weihua Pu Li Wang Jianguo Ren Changyin Jiang Chunrong Wan 《Electrochimica acta》2007,52(11):3651-3653
A novel process was proposed to synthesize nano Sb-encapsulated pyrolytic polyacrylonitrile composite for anode material in lithium secondary batteries. The preparation started with the dissolution of SbCl3 and polyacrylonitrile (PAN) in dimethylformamide (DMF) solution, followed by the addition of KBH4 to reduce Sb3+ in the solution. The Sb composite was obtained by pyrolysis of the Sb/PAN mixture that precipitated out when the DMF solution was added by plentiful water. The TEM analysis showed that about 100-200 nm Sb particles were embedded by the pyrolyzed PAN, which provided a conductive matrix to relieve the morphological change of Sb during electrochemical cycling. As-prepared composite presented good cycleability for lithium storage. The proposed process paves an effective way to prepare high performance alloy based composite anode materials for high performance lithium-ion batteries. 相似文献
994.
X‐ray diffraction methods, DSC thermal analysis, and polarized light microscopy (PLM) were used to investigate the structural changes of nylon 66/clay nanocomposites. PA 66/clay nanocomposites were prepared by the method of melt intercalation. The results indicate that the addition of the intercalated organo‐montmorillonite (OMMT) can induce generation of the β‐form crystal of PA 66 and substantially affect the arrangement of molecules in the α‐form crystal, although the crystallinity scarcely changes. Also, the DSC results indicate that the addition of OMMT in the PA 66 matrix leads to increases of crystallization temperatures and the full width at half maximum (FWHM) of the exothermic peaks. Moreover, the viscosity factor is the main influence on FWHM of the exothermic peaks of PA 66/clay nanocomposites. The results of nonisothermal crystallization kinetics show that OMMT has the effect of heterogeneous nucleation and leads to the decrease of the size of the spherocrystal. The heterogeneous nucleation effects of OMMTs influence the mechanism of crystallization and the growth mode of PA 66 crystals. PLM photographs verify that the size of spherocrystal is decreased and visually confirm the theory of crystallization kinetics. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 756–763, 2005 相似文献
995.
聚氨酯防水涂料是当今最有效的柔性防水材料之一,介绍了聚氨酯防水涂料的发展状况,并对其市场前景进行了展望。 相似文献
996.
Boon-Seang Chu Sosaku Ichikawa Sumiyo Kanafusa Mitsutoshi Nakajima 《Journal of the American Oil Chemists' Society》2007,84(11):1053-1062
This work was initiated to prepare protein-stabilized β-carotene nanodispersions using emulsification–evaporation. A pre-mix
of the aqueous phase composed of a protein and hexane containing β-carotene was subjected to high-pressure homogenization
using a microfluidizer. Hexane in the resulting emulsion was evaporated under reduced pressures, causing crystallization and
precipitation of β-carotene inside the droplets and formation of β-carotene nanoparticles. Sodium caseinate (SC) was the most
effective emulsifier among selected proteins in preparing the nanodispersion, with a monomodal β-carotene particle-size distribution
and a 17-nm mean particle size. The results were confirmed by transmission-electron microscopy analysis. SC-stabilized nanodispersion
also had considerably high ζ-potential (−27 mV at pH 7), suggesting that the nanodispersion was stable against particle aggregation.
Increasing the SC concentration decreased the mean particle size and improved the polydispersity of the nanodispersions. Nanodispersions
prepared with higher β-carotene concentrations and higher organic-phase ratios resulted in larger β-carotene particles. Although
increased microfluidization pressure did not decrease particle size, it did improve the polydispersity of the nanodispersions.
Repeating the microfluidization process at 140 MPa caused the nanodispersions to become polydisperse, indicating the loss
of emulsifying capacity of SC due to protein denaturation. 相似文献
997.
998.
The objective of this work is to study the transfer of oxygen from gas to liquid phase in an electroflotation cell. The measurements
were performed in a laboratory scale cell using insoluble electrodes, titanium coated with ruthenium oxide as anode and stainless
steel as cathode. The volumetric mass transfer coefficient K
L
a, was characterized for clean tap water as liquid phase for different values of current density (J). The global coefficient
of mass transfer based on the liquid film, K
L
, and the specific interfacial area, a, were characterized. A model which relates K
L
a to current density was established. Different evaluation criteria of oxygen transfer in electroflotation process were determined
and compared with other aeration process. 相似文献
999.
1000.
冰箱门胆真空吸塑成型模具抽芯机构设计 总被引:1,自引:0,他引:1
在充分分析斜滑块抽芯机构运动及受力状态的基础上,介绍了一种利用脱模力抽芯的非气动抽芯机构设计方法,采用该方法设计的冰箱门胆吸塑模具结构紧凑、抽芯可靠、生产效率高。 相似文献