D-泛酸钙的合成技术及应用

主要介绍了D 泛酸钙的合成技术及其应用     

Synthesis and Spectral Properties of Mixed-Ligand Complexes of Lanthanide Perchlorate with Bis-(phenylsulfinyl)ethane and Organic Lewis Bases

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甲基磺酸镧催化缩醛化反应性能的研究

以正辛醛和乙二醇为原料,甲基磺酸镧为催化剂,合成了正辛醛缩乙二醇。采用正交实验法考察了影响收率的因素。其最优条件为,正辛醛∶乙二醇∶催化剂∶带水剂为1m o l∶1.2m o l∶7.5g∶75mL,反应在回流温度下进行,反应时间3.0h,收率可达87.2%。用此方法合成了其它三种缩醛,同样获得满意结果。证明甲基磺酸镧对缩醛化反应具有较高的催化活性。     

天然气制液态烃新工艺

丰富的天然气资源,特别是边远地区分散的中小天然气田和油气共生的油气田的天然气,由于产量达不到管线长输的规模效益,又远离消费市场,很难开发利用.为此,作者在天然气两段催化氧化制合成气和费-托合成研究的基础上,提出了一种流程较短、投资和操作费用较低的天然气合成液态烃新工艺,可将丰富的天然气资源,特别适合将边远地区分散的中小天然气田的天然气转化为无硫、无氮、无芳烃、无重金属污染和便于输运的优质石蜡基液态产品.该产品可经轻度加氢改质得到高品质的柴油掺合组分、润滑油基础油高等附加值产品.该工艺副产的燃料气可用于发电,或作为燃料气使用.     

IC—V100电台锁相环频率合成器

本文从频率合成器的结构、功能入手,详细阐述了频率编程的原理及方法。     

Dependence of critical current density on microstructure and processing of high-Tc superconductors

Microstructural origins for reduced weak-link behavior in high-J_c melt-processed YBCO, spray pyrolyzed thick films of Tl-1223, metallic precursor Y-124 polycrystalline powder-in-tube (PIT) wires and PIT Bi-2212/2223 are discussed. Since the materials studied are the highest J_c, polycrystalline, high-T_c superconductors fabricated worldwide, the results provide important guidelines for further improvements in superconducting properties, thereby enabling practical applications of these materials. It is found that strongly linked current flow within domains of melt-processed 123 occurs effectively through a single crystal path. In c-axis oriented, polycrystalline Tl-1223 thick films, local in-plane texture has been found to play a crucial role in the reduced weak-link behavior. Formation of “colonies” of grains with a common c-axis and modest in-plane misorientation was observed. Furthermore, a colony boundary in general has a varying misorientation along the boundary. Large regions comprised primarily of low angle boundaries were observed. Percolative transport through a network of such small angle boundaries appears to provide the nonweak-linked current path. Although powder-in-tube BSCCO 2212 and 2223 also appear to have a “colony” microstructure, there are some important differences. Colonies in BSCCO consist of stacks of grains with similar c-axis orientation in contrast to colonies in Tl-1223 films where few grains are stacked on top of one another. Furthermore, most grains within a colony in BSCCO have the same lateral dimensions as that of the colony, resulting largely largely in “twist” boundaries. Further microstructural characterization of high-J_c PIT 2212 and 2223 is currently underway. In the case of Y-124 wires, weak macroscopic in-plane texture is found. Additional measurements are underway to determine if a sharper, local in-plane texture also exists. It is found that in three of the four types of superconductors studied, reduced weak-link behavior can be ascribed to some degree of biaxial alignment between grains, either on a “local” or a “global” scale.     

Growth of CeO_2, Y_2O_3 Buffer Layers for YBCO Coated Conductor

~~Growth of CeO_2, Y_2O_3 Buffer Layers for YBCO Coated Conductor     

Effect of pretreatments and freezing rate on the firmness of potato tissue after a freeze–thaw cycle

The texture of potato tissue after a freeze–thaw process using different freezing rates and different pretreatments was analysed, in order to select the best strategy for optimum preservation of the textural characteristics of pre‐frozen potato. Ten blanching conditions were tested and a two‐step blanching process with calcium chloride (0.07 g mL^?1) proved the most effective in protecting the tissue after a freeze–thaw process (maximum load force around 10–55% of the raw tissue, depending on potato batch, for air‐blast freezing and 20–60% for immersion freezing). Vacuum impregnation at 100 and 400 mbar, even when followed by different pre‐drying treatments to remove excess water, was very detrimental to resistance to a freeze–thaw process (maximum load force below 10% of the raw tissue for air‐blast freezing and below 20% for immersion freezing). Microstructure analysis confirmed better tissue integrity retention with ethyleneglycol immersion freezing instead of air‐freezing. Differences were found between batches with a 6‐month difference in storage time, indicating that the fresher batch was more suitable for freezing.     

丙烯酸高碳醇酯的合成

介绍了降凝剂中间体丙烯酸高碳醇酯的合成和产品分离提纯方法。考察了合成条件对酯化反应的影响，结果表明，在原料丙烯酸与十八醇摩尔比1．2：1，阻聚剂对苯二酚用量占原料总量1．5％，催化剂对甲苯磺酸用量占原料总量1．5％，反应温度80-86℃，回流反应时间6h条件下，酯化率最高达89％。产品分离提纯方法与传统分离方法比较，所需分离时间短，洗涤用水量少，而产品收率远高于传统分离方法，达95％以上。     

环氧乙烷合成乙二醇的研究进展

介绍了环氧乙烷合成乙二醇的主要生产方法，包括以壳牌、联碳化学公司以及Halcon—SD公司为代表的环氧乙烷直接水合法，环氧乙烷催化水合法和碳酸乙烯酯法，后两种乙二醇生产方法是目前国内外研究开发的热点。催化剂体系是催化水合法工艺的关键，重点介绍了国内外各主要公司对催化剂体系的研究进展及使用效果；碳酸乙烯酯法分为乙二醇和碳酸二甲酯联产法以及碳酸乙烯酯水解法，详细介绍了国内外各主要公司对该技术的研究进展，包括工艺流程、催化剂体系等方面。将3种乙二醇生产方法进行技术经济比较，结果表明，催化水合法和碳酸乙烯酯法在原料消耗和能耗方面占优势。并对我国乙二醇生产工艺技术提出建议。