钌基Deacon催化剂的研究进展

大量副产氯化氢已成为制约众多涉氯行业发展的共性难题。催化氧化氯化氢制氯气,即Deacon过程,是一种实现工业副产氯化氢循环利用的可持续发展途径。钌基Deacon催化剂具有高活性和高稳定性的优异特点,并且已成功应用到工业过程。根据催化剂种类的不同将氯化氢氧化机理分为两种:以铜基催化剂为代表的种类为MarsvanKrevelen机理,以钌基催化剂为代表的种类遵循Langmuir-Hinshelwood机理。分析和总结出钌基Deacon催化剂是以RuO_2和金红石晶型的氧化物载体为基本组成,其结构是由RuO_2呈二维薄膜形态包覆在金红石晶型载体表面形成的核壳结构。详述改进型钌基催化剂在降低贵金属负载量和提高稳定性两个方面的研究进展,并展望未来降低Deacon催化剂成本的发展方向。     

Innovation of novel ‘Tab in Tab’ system for release modulation of milnacipran HCl: optimization,formulation and in vitro investigations

The study was aimed toward development of modified release oral drug delivery system for highly water soluble drug, Milnacipran HCl (MH). Novel Tablet in Tablet system (TITs) comprising immediate and extended release dose of MH in different parts was fabricated. The outer shell was composed of admixture of MH, lactose and novel herbal disintegrant obtained from seeds of Lepidium sativum. In the inner core, MH was matrixed with blend of hydrophilic (Benecel^®) and hydrophobic (Compritol^®) polymers. 3² full factorial design and an artificial neuron network (ANN) were employed for correlating effect of independent variables on dependent variables. The TITs were characterized for pharmacopoeial specifications, in vitro drug release, SEM, drug release kinetics and FTIR study. The release pattern of MH from batch A10 containing 25.17% w/w Benecel^® and 8.21% w/w of Compritol^® exhibited drug release pattern close proximal to the ideal theoretical profile (t_50% = 5.92?h, t_75% = 11.9?h, t_90% = 18.11 h). The phenomenon of drug release was further explained by concept of percolation and the role of Benecel^® and Compritol^® in drug release retardation was studied. The normalized error obtained from ANN was less, compared with the multiple regression analysis, and exhibits the higher accuracy in prediction. The results of short-term stability study revealed stable chataracteristics of TITs. SEM study of TITs at different dissolution time points confirmed both diffusion and erosion mechanisms to be operative during drug release from the batch A10. Novel TITs can be a succesful once a day delivery system for highly water soluble drugs.     

Mucoadhesive liposomes as ocular delivery system: physical,microbiological, and in vivo assessment

Background: Mucoadhesive drug delivery is a promising strategy to overcome ocular biopharmaceutical constraints. Objective and methods: Ciprofloxacin HCl-loaded reverse phase evaporation liposomes were coated with different concentrations and molecular weights of mucoadhesive biocompatible chitosan polymer to form chitosomes. This colloidal mucoadhesive system was evaluated in vitro and in vivo with respect to deliver the antibiotic to ocular surface. Results and conclusion: The results obtained pointed out that liposome coating process resulted in entrapment efficiency reduction and higher chitosan concentration, and molecular weight showed a more pronounced effect. No morphological differences between coated and uncoated liposomes were observed. Diffusion was the drug release mechanism from chitosomes. Concerning rheological behavior, pseudoplastic flow was characteristic to the prepared chitosomal dispersions. In addition, chitosan coating improved the ocular permeation of ciprofloxacin HCl. Microbiologically; this formulated system enhanced antimicrobial activity of ciprofloxacin HCl against both Gram-positive and Gram-negative bacteria. Moreover, this mucoadhesive system was able to inhibit the growth of Pseudomonas aeruginosa in rabbits' eyes for 24 hours when compared to the marketed preparation. In vivo bacterial conjunctivitis model elucidated that symptoms were controlled by the prolonged release formulation such as that done by the marketed product.     

Kinetic study on selective extraction of HCl and H3PO4 in a microfluidic device☆

In the extraction method for preparing KH2PO4, one of the key processes is the selective extraction of HCl over H3PO4. In our work, extraction kinetic studies have been carried out in a microfluidic device with a coaxial microchannel, using the extractant of 33.3%(by volume) trioctylamine (TOA) dissolved in n-octanol, with differ-ent aqueous phases:the HCl solution, the H3PO4 solution, and H3PO4 and KCl solutions of different concentra-tions. The changes of the extraction efficiency of HCl and H3PO4 and the selectivity for HCl along with the residence time were investigated. We found that fast extraction kinetics could be realized in microfluidic devices, and that HCl could be extracted faster than H3PO4 due to smaller mass transfer resistance and much stronger re-action between HCl and TOA. For the extraction of H3PO4 and KCl solutions, the selectivity for HCl first increased and then decreased when TOA was in excess of H3PO4 in the initial feeds, and in contrast, always increased when H3PO4 was in excess of TOA in the initial feeds. The diverse changes of selectivity for HCl along with the residence time indicate that a dynamic control of selectivity in microfluidic devices may be important and accessible for im-proving the KH2PO4 conversion efficiency in extraction method.     

煤燃烧过程中氯析出特性的试验研究

采用石英管管式炉进行试验，研究了温度、气氛、空气流量、停留时间对煤中氯析出特性的影响。燃烧过程中煤中氯基本上是以HCl形式析出。200℃开始氯析出，到600℃时90％氯已析出。1000℃氧化性气氛燃烧时，煤中氯的转化在10min内基本完成，过量O2对转化率影响不大，但O2量不足却会造成HCl转化率明显下降。最后给出了煤燃烧过程中氯析出动力学方程。     

合金材料在高浓度HCl气体中的腐蚀特性实验研究(Ⅱ)

在实验室小型流化床焚烧炉中,比较了0Cr17Ni14Mo2、T91、1Cr13、TP304、TP347、0Cr25Ni20和复合板等7种材料600℃下在高浓度HCl气体中的腐蚀情况。通过对材料的腐蚀表面进行了X射线能谱(EDX)和扫描电子显微镜(SEM)分析发现,材料0Cr17Ni14Mo2、T91及复合板抗腐蚀性能较好,1Cr13、TP347抗腐蚀性能较差。     

小麦面筋蛋白盐酸脱酰胺工艺优化及其酶解敏感性

文以小麦面筋蛋白为原料,优化了盐酸对小麦面筋蛋白的脱酰胺工艺,比较了最佳脱酰胺工艺下的小麦面筋蛋白在胰酶、风味蛋白酶和碱性蛋白酶酶解过程中蛋白回收率和水解度的变化,并对其酶解36 h酶解液的自由基吸收能力(ORAC)抗氧化特性进行分析评价。研究结果表明,盐酸脱酰胺的工艺条件是:小麦面筋蛋白浓度为24%,0.30 mol/L的HCl,65℃,24 h脱酰胺;在该工艺条件下,胰酶酶解液蛋白回收率和水解度最高,酶解效果最好;高脱酰胺程度小麦面筋蛋白在胰酶酶解36h后酶解液的蛋白回收率和水解度高于低脱酰胺程度的酶解液;ORAC抗氧化特性分析表明高脱酰胺程度小麦面筋蛋白酶解液的ORAC值高于低脱酰胺程度的酶解液,其ORAC值最高为(689.67±10.22)μmol Trolox/g。     

盐酸水解DNS比色法快速测定甘薯淀粉含量的标准方法研究

以经典费林试剂滴定法为标准法，对6mol/L盐酸水解，3，5－二硝基水杨酸比色（简称DNS比色法）快速测定甘薯淀粉含量标准化方法进行了研究，探讨了准确度和精密度，提出了消除胡萝卜素和花青素色素干扰的方法。     

3,5-二甲基-2-(2-氟苯)-2-吗啉醇盐酸盐的合成

1-(2-氟苯)-2-溴-1-丙酮在非质子极性溶剂中经胺化、环合反应,最后酸化得到3,5-二甲基-2-(2-氟苯)-2-吗啉醇盐酸盐(产率82.7%)。其结构均得到IR和1H NMR确证。整个合成路线具有反应条件温和、反应时间短、收率高等优点。