结晶分离技术新进展

概述了结晶分离理论和模拟优化的发展,综述了冷却剂直接接触冷却结晶、反应结晶、蒸馏-结晶耦合、氧化还原-结晶液膜、萃取结晶、磁处理结晶等结晶分离方法.合理设计结晶器及结晶工艺是实现结晶分离工业化的可靠保证,对降膜结晶装置、Bremband结晶工艺和板式结晶器进行评价.指出今后需深入进行新型结晶分离装置与工艺、工艺的工业化、结晶过程传热传质机理方面的研究.     

环保型单组分低温磷化液的研制与应用

从环保,质量和处理工艺的角度对单组分灰的彩膜磷化液的配方设计,处理工艺等进行了详细的论述,并通过大量实验提出了该产品的最佳配方及处理工艺,该工艺污染小,成本低,使用方便,为发展我国新一代环保型磷化液进行了有的探索和尝试。     

Synthesis of a new polyarylenvinylene derivative based on a terstyryl group linked by a maleimide group

Summary The new polyarylenevinylene, structurally based on a terstyryl group linked by a maleimide group, was prepared from a new dibrominated diphenylmaleimide monomer and p-divinylbenzene by Heck-type Pd catalyzed polycondensation. The polymer was soluble in common organic solvents and had M _w and the polydispersity index of 73,600 g/mol and 5.0, respectively. Analysis with IR and NMR indicated that the polymer had a stereoregular vinylene sequence in the backbone of Z, E, E-configurations in series. The polymer showed optical absorption maximums at 353 nm and 444 nm and the bright orange red-colored photoluminescence at 570 nm in a solution and 590 nm in a film. Received: 19 September 2000/Revised version: 4 December 2000/Accepted: 11 December 2000     

双波长分光光度法同时测定日落黄与柠檬黄

采用双波长分光光度法同时测定食品中日落黄与柠檬黄,其标准曲线的相关系数为r柠＝0．9999,r日＝0．9998,平均回收率也符合要求,该方法简便,所使用仪器普遍。     

高浓度SO_2转化技术在金隆公司的应用

介绍高浓度SO2 烟气〔φ(SO2 ) 10 %～ 13%〕制酸装置转化系统的工艺设计参数和实际运行情况。采用环状中、低温催化剂和含铯环状低温催化剂 ,合理分配各段催化剂的装填量和转化率 ,对设备和管道进行良好的热膨胀补偿。装置运行情况稳定 ,转化率达到 99 8%     

硫氧还蛋白及其L97F变体酶切后片段自身重新结合为同源二聚体的稳定性和动力学研究

为了进一步研究蛋白质酶切后重新结合成同源二聚体时功能区域中残基的影响。本文选用硫氧还蛋白（TRX）和硫氧还蛋白变体（TRXL97F）酶切后得到的两组片段：N片段（1－72）和C片段（74－108）作为研究对象。比较排在79位的残基的改变对N片段（1－73）和C片段（74－108）作为研究对象。比较排在79位的残基的改变对N片段（1－73）和C片段（74－108）重新结合成同源二聚体的影响,得到以下结论：1．TRX中处于β折叠状态的βR区域（P76,T77,L78,L80,F81和K82）^5中残基由链变为芳香环使N片段和C片段重新聚合成非共价同源二聚体的速率常数有所减小。2．这一变化对形成的同源二聚体的稳定性影响不大。     

西仑吉肽的合成制备

西仑吉肽(cilengitide)是一个含RGD序列人工改造设计得到的生物活性环肽,对整合素α_vβ₃具有较高的亲和性和选择性。本研究主要对西伦吉肽合成方法进行研究：采用固液相结合合成法,以二氯树脂为固相载体,以HBTU、PyBOP为缩合剂,固相合成线性肽后液相合成环肽,采用制备型反相高效液相色谱法进行纯化。产品纯度为98.3%,总收率为28.2%。该合成方法简单易行,产品纯度较高,适合用于西仑吉肽工业生产。     

利用共存杂质分析甲基苯丙胺的合成信息

通过测定甲基苯丙胺样品中共存杂质的种类与含量,推测其合成途径及来源。将含MA样品用无水乙醇溶解,气相色谱-质谱法分析其组分,归-法计算相对百分含量。结果7个样品的甲基苯丙胺含量在9．81％-97．3％之间,其中3个样品含麻黄碱,含量在4．15％-5．52％;2个样品的共有成分为l-苯基-2-丙酮,含量分别为0．506％,0．696％;剩余2个样品既不含麻黄碱,也不含1-苯基-2-丙酮,甲基苯丙胺含量仅为23．5％和9．81％。推测7个样品中3批样品来源于麻黄碱合成途径,2批样品是苯丙酮合成途径,另2批样品由少量甲基苯丙胺混合其他成分配制而成。目前,麻黄碱仍是合成甲基苯丙胺的主要来源。     

Novel‐modified kaolin for enhancing the mechanical and thermal properties of poly(vinyl chloride)

Novel surface‐modified kaolin with liquid‐like behavior was prepared. The characteristics of the solvent‐free kaolin fluid were evaluated by using Fourier transform infrared spectroscopy, WAXD, thermogravimetric analysis, and transmission electron microscopy. The polyvinyl chloride (PVC)/solvent‐free kaolin fluid composites were also fabricated via melt mixing. Owing to the novel surface modification, the hydrophilic kaolin surface grafted long organic chains, which made that the solvent‐free kaolin fluid could be well dispersed in PVC matrix and firmly integrated with the PVC matrix. The resulted composites exhibited better heat resistance and mechanical properties than neat PVC resins. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

Molecular and structural analysis of epoxide‐modified recycled poly(ethylene terephthalate) from rheological data

A multifunctional epoxide chain extender (ADR4370S) was used to increase the molecular weight of recycled poly(ethylene terephthalate) (R‐PET). The extension processing was carried out by melt mixing reaction. The effects of ADR4370S content on the molecular structure [molecular weight, molecular weight distributions (MWDs), branching, and gel‐like structures] of modified R‐PET were rheologically investigated. The results showed that the complex and apparent viscosity of the modified R‐PET were larger than those of unmodified one. The solid‐like behavior of R‐PET was enhanced after the reactive modification. The increments of balancing torque, reaction peak, and shear‐thinning behavior became more pronounced by increasing the concentration of ADR4370S. Reactive modification was characterized by the presence of long‐chain branching resulted in a wider MWD. Modified Cole–Cole plots demonstrated a shift toward higher storage modulus values at a given loss modulus value for the modified R‐PET samples. High concentration of ADR4370S (>1.5 wt%) resulted in a polymeric structure near the sol–gel transition point whose linear viscoelastic properties obeyed scaling law. The relaxation time was prolonged with the amount of ADR4370S increase. The decrease in the melt point and crystallization temperature of the modified R‐PET was correlated to the presence of chain branching. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers