四川广元市苍溪天然气化工基地规划方案

四川广元市苍溪利用超大储量天然气田的优势可发展天然气化工基地。乙烯生产工艺路线有石油乙烯路线即石脑油裂解制乙烯、煤制甲醇生产烯烃路线和天然气制甲醇生产烯烃路线。石油制烯烃路线需与大炼厂相结合,工艺流程及环境治理复杂,设备多造成投资费用大、能耗高,而且原料石油价格昂贵。乙烯生产由石油乙烯向天然气或煤炭制甲醇生产乙烯转变已成为今后的工艺技术发展方向。四川广元市苍溪天然气化工基地规划方案为:建天然气为原料制50×104t/a甲醇的装置共4套(共生产甲醇200×104t/a),天然气制甲醇生产乙、丙烯40×104t/a的装置共两套(共产乙、丙烯80×104t/a)。基地总年用天然气16×108m3/a,用电10×104kW,总投资约100亿元,总年产值约92亿元,利税约26.5亿元。甲醇生产采用国内开发已成功用于大规模生产的节气减排CO2的二段炉纯氧自热转化合成甲醇工艺;甲醇脱水制乙、丙烯技术也采用国内开发已实现工业化生产的新工艺。规划设计采用的工艺技术先进、能耗低、投资省、效益好、天然气中碳元素充分利用。天然气制乙、丙烯的生产成本比以石油为原料的低,且无环境污染,产品有竞争力。     

三维针刺C/SiC刹车材料的摩擦磨损性能

通过化学气相渗透法(CVI)结合反应熔体浸渗法(RMI)制备了三维针刺,C/SiC刹车材料 , 利用 MM21000型摩擦磨损试验机系统研究了C/SiC刹车材料的摩擦磨损性能,采用光学显微镜和扫描电子显微镜分别对摩擦表面和磨屑形貌进行了观察。结果表明:干态刹车条件下,当初始刹车速度相同时,摩擦系数随着刹车压力的升高而逐渐降低;当刹车压力相同时,摩擦系数随着初始刹车速度的增加先升高后降低。湿态摩擦性能衰减小(衰减约8 %) 、恢复快;静态摩擦系数高(为0. 56～0. 61),摩擦系数随着初始刹车温度的升高而显著降低。当刹车压力相同时,磨损率随着初始刹车速度的增加而增大;当初始刹车速度大于20 m/s时,刹车压力的增大使磨损率显著增加。      

6．3MVA电炉电极带电压放系统及放进实践

介绍了6．3MVA电炉的电极带电压放系统,并对本系统在实际使用过程中存在的液压系统的远程调压和泄荷回油方式两个问题进行了分析,提出了改进方案,方案实施后,获得明显效果。     

三维针刺C/SiC复合材料显微结构演变分析

以三维针刺碳毡作为预制体,采用树脂浸渍-热解工艺制备C/C多孔体,然后采用反应熔体浸渍法(Reactive melt infiltration,RMI)对C/C多孔体分别浸渗Si和Si-Mo合金制备C/SiC复合材料。首先研究了C/C多孔体制备过程中的显微结构演变。结果表明,浸渍过程中树脂主要填充在纤维束内小孔隙中,热解后裂纹增多,生成网格状C/C亚结构单元;高温热处理使C/C复合材料裂纹进一步扩展,石墨化度提高,束内闭气孔打开,从而为RMI渗Si提供通道。然后对C/C多孔体分别渗Si和Si-Mo合金所得材料的物相组成和显微结构进行对比分析。发现纯Si浸渗得到的复合材料残余Si较多,束内纤维受损严重;而浸渗Si-Mo合金可以减少残余Si含量,束内纤维受损轻微,仍保持着完整的C/C亚结构单元。     

^211At通过DTPA酸酐标记IgG

研究了２１１Ａｔ通过二乙撑三胺五乙酸（ＤＴＰＡ）酸酐标记人免疫球蛋白Ｇ（ＩｇＧ）的方法。合成ＤＴＰＡ酸酐后与人ＩｇＧ反应，制得ＤＴＰＡ－ＩｇＧ。Ｎａ２１１Ａｔ溶液与分离纯化后的ＤＴＰＡ－ＩｇＧ在室温下反应３０ｍｉｎ，经ＳｅｐｈａｄｅｘＧ５０柱分离纯化，得２１１Ａｔ－ＤＴＰＡ－ＩｇＧ的０．１ｍｏｌ／ＬＰＢＳ淋洗液。整个标记过程可在１．５ｈ完成，全程标记率在６０％以上。测定了２１１Ａｔ－ＤＴＰＡ－ＩｇＧ在体外的稳定性，并通过比较标记物与Ｎａ２１１Ａｔ注射液在ＮＩＨ小鼠体内的分布和代谢，评价了２１１Ａｔ－ＤＴＰＡ－ＩｇＧ在体内的稳定性。     

热带粗轧机组立轧过程的三维有限元模拟

本文采用全三维刚塑性有限元法对室温下的铝和不同温度下的２Ｓ－Ａｌ平辊侧压稳定变形过程进行了解析，计算结果和实测值吻合较好，较明显地提高了计算精度。并提出用超薄单元近似处理奇异点的办法，使计算编程简化，能迅速地得到较好的解     

In-situ fabrication of laminated SiC/TiSi2 and SiC/Ti3SiC2 ceramics by liquid silicon infiltration

The laminated silicon carbide/titanium silicon (SiC/TiSi₂) and silicon carbide/titanium silicon carbide (SiC/Ti₃SiC₂) ceramics were successfully designed and fabricated by liquid silicon (Si) infiltration. When the thickness of TiC layer was 150 and 450?µm, the TiSi₂ and Ti₃SiC₂ phases were the main products in the TiC layer, respectively. The as-fabricated structural unit of laminated SiC/Ti₃SiC₂ ceramics consisted of five layers of functionally graded materials, which has multiscale layered structure containing macro-layered structure and nano layered structure. The generation of hierarchical structure was attributed to the diffusion of Ti elements and in-situ formation of TiSi₂ and Ti₃SiC₂. The growth direction of Ti₃SiC₂ was anisotropic, thus providing more paths for the crack propagation via deflection, branching, and delamination during fracture process. However, the crack propagation inside the Ti₃SiC₂ phase included the pull out, bridging, lamination, deflection, and fracture of the single layer, which are the energy absorption and damage tolerance mechanisms of the Ti₃SiC₂ phase.     

Effect of sesame protein isolate in partial replacement of milk protein on the rheological,textural and microstructural characteristics of fresh cheese

Soft cheeses were manufactured from bovine milk with the addition of 0–12% sesame protein isolate (SPI) were utilised to investigate rheology, texture and microstructure at different stages of cheese making. SPI addition reduced the speed of milk fermentation, kappa‐casein proteolysis of rennet and elongated the time of cheese curd formation. Renneted milk storage modulus G′_60min was decreased and coagulation time increased with increasing SPI content. Low SPI supplements (4% and 8%) enhanced the hardness, cohesiveness, adhesiveness and gumminess of the soft cheese, while high SPI addition (12%) deteriorated the texture. In the cheese curd gel matrix, SPI distributed as specific SPI‐gel clusters on the surface of curd fractures, stacked or fused with ball‐shaped casein micelles and wrapped up to casein gel strands. In summary, SPI actively interacted with casein colloid throughout the cheese making process.