农药制剂中助剂使用状况调研及风险分析

农药助剂在农药制剂生产中必不可少,是农药制剂产品的必要组成成分。农药助剂曾被误认为是对环境和人类健康无害的惰性物质,因此我国农药相关管理规定中没有对农药助剂的环境安全进行登记管理。通过对2010年和2011年拟申请登记的农药制剂剂型、助剂品种、作用、含量等基本数据的调查发现,农药助剂具有以下特征:1)调查农药品种368个,但出于商业机密考虑,仅51.6%的调查产品提供了农药助剂信息。2)提供助剂信息的190个农药制剂产品中使用的助剂品种数量为104种,其中玫瑰精、二甲苯、甲苯、环己酮、壬基酚等助剂或其代谢物具有健康风险。3)每种农药制剂中含有3~4种助剂成分,助剂含量占制剂量的1%~99%。     

甲醇双效精馏系统的优化研究

为优化焦炉气制甲醇工艺中甲醇双效精馏系统,利用流程模拟技术对系统进行模拟分析,对比分析模拟数据与实际数据,提出甲醇双效精馏系统的优化措施。结果表明:模拟数据与实际数据基本吻合,模拟状态下每天可产甲醇350.4 t,与实际产量350 t相符,说明Wilson方程可用于甲醇-水体系。甲醇双效精馏系统中所需蒸汽量为9.83 t/h,而实际工况中蒸汽使用量为12.2 t/h,实际工况中的蒸汽使用量仍偏大,应降低蒸汽使用量;加压精馏塔、常压精馏塔最佳回流比分别为1.50和0.94;加压精馏塔中第25块塔板为灵敏板,常压精馏塔中第18、38块塔板作为灵敏板,日常操作中应重点关注以上塔板温度的变化。     

Rapid and large‐scale separation of magnetic nanoparticles by low‐field permanent magnet with gas assistance

Bubbles can be used to greatly improve the speed of magnetic separation (MS) and overcome the limitation of magnetic force on the capture distance, making low‐field MS highly efficient and easily scalable. This novel method leads to the development of a medium‐free continuous gas‐assisted magnetic separator on small pilot scale using low‐field permanent magnet. This separator is demonstrated highly efficient for recovery of proteins‐loaded magnetic nanoparticles from large volume biosuspension. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3101–3106, 2014     

Quality assurance of Chinese herbal medicines: Procedure for multiple‐herb extraction

A quality assurance (QA) procedure for multiple‐herb extraction, which takes into account the existence of common chemical markers and multiple‐herb‐extraction effects, has been developed for producing Chinese herbal medicines (CHMs) of consistent quality. The experimental method for determining related correlation function of the multiple‐herb‐extraction effect was designed. A systematic solution strategy was also developed to appropriately decompose the multiple‐herb extraction system into several subsystems for obtaining solution(s) and determining the overall behavior of the system. An example of QA of Danshen–Gegen (DG) decoction was used to demonstrate the QA procedure. An H9c2 cell assay was used to test the efficacy of consistent quality DG decoctions prepared by different herb combinations with different material costs of herbs. It was observed that a multiple‐herb‐extraction effect was present in the aqueous extraction of Danshensu and this effect was depended on the extraction solvent. The possible mechanism of this multiple‐herb‐extraction effect in the aqueous DG extraction was speculated to be the change of initial pH value of the aqueous extraction solvent by an unknown component from Gegen. The experimental chemical marker concentrations fell within ±10% of the specified chemical marker compositions by using the amount of herb from each herb class as predicted by the QA model. Furthermore, an H9c2 cell assay was used to test the efficacy of three consistent quality DG extracts, which were produced by different herb combinations with different material costs of herbs. The results showed that the three DG extracts provided consistent biological efficacy against menadione‐induced toxicity. This study extended a recently developed QA procedure of single‐herb extraction to multiple‐herb extraction. It provides a solution of QA in extraction, which is one of the most important unresolved problems in the modernization of traditional Chinese medicines. With this modified model and the companion experiments, the amount of herbs needed from different quality classes to produce a multiple‐herb formula CHM product decoction with consistent quality can be exactly determined. © 2014 American Institute of Chemical Engineers AIChE J 60: 4014–4026, 2014     

Preparation of anion exchange membrane based on homogeneous quaternization of bromomethylated poly(arylene ether sulfone)

This article presented the synthetic and preparation route of quaternary ammonium functionalized anion exchange membranes (AEMs), which were derived from an engineering plastics polymer, poly(arylene ether sulfone) with 3,3′,5,5′‐tetramethyl‐4,4′‐dihydroxybipheny moiety (PAES‐TM). The benzylmethyl groups on the main‐chain of PAES‐TM were converted to the bromomethyl groups via a radical reaction, thereby avoiding complicated chloromethylation, which required carcinogenic reagents. The chemical structure of the bromomethylated PAES was characterized by ¹H NMR spectrum. Following a homogeneous quaternization with trimethylamine in the solution, a series of flexible and tough membranes were obtained by a solution casting and anion exchange process. The ion exchange capacity values were ranging from 1.03 to 1.37 meq g^?1. The properties of the membranes, including water uptake, hydroxide conductivity, and methanol permeability were evaluated in detail. The AEM showed a high conductivity above 10^?2 S cm^?1 at room temperature and extremely low methanol permeability of 4.16–4.94 × 10^?8 cm² s^?1. The high hydroxide conductivity of TMPAES‐140‐NOH could be attributed to the nano‐scale phase‐separated morphology in the membrane, which was confirmed by their transmission electron microscopy images. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40256.     

基于PLC的燃煤锅炉脱硝控制系统

聚酯生产装置共有5台58 600MJ的燃煤锅炉,为了使锅炉烟气中的NOx达标排放,在烟气排放前增加了脱硝装置,脱硝工艺采用选择性非催化还原法,以S7-300 PLC作为其控制核心,采用WinCC设计操作站的监控和数据采集系统,重点给出了模拟量的输入与转换、PID控制回路和氨水流量累积过程的组态和程序代码。     

封闭王水溶解联合ICP-MS法测定地质样品中痕量金

探讨了采用封闭王水溶解联合电感耦合等离子体质谱法测定地质样品中痕量金的方法。经实验验证,本方法不仅能显著提高金的溶出度,而且操作简便、快速、结果可靠。尤其适用于地质样品中痕量金含量的测定。     

NR/SiO_2复合体系结合胶及动态力学性能研究

研究了白炭黑用量和Si69原位改性对NR/SiO2复合体系结合胶含量及其与动态力学性能之间关系的影响。结果表明,随着白炭黑用量的增大,2种复合体系(NR/SiO2/Si69和NR/SiO2)结合胶含量均呈现先增大后减小的趋势。当白炭黑用量达到临界值时,复合体系结合胶含量最大,此时Payne效应开始显现。当白炭黑用量超过临界值时,复合体系结合胶含量减小,形成完善的填料网络结构,出现明显的Payne效应。与NR/SiO2复合体系相比,NR/SiO2/Si69复合体系结合胶含量大大提高,白炭黑用量的临界值也相应提高,Payne效应减弱。     

黑曲霉葡萄糖氧化酶在毕赤酵母中的表达及其高效发酵研究

葡萄糖氧化酶是一类能催化β-D-葡萄糖生成葡萄糖酸-8-内酯的酶类,在食品、药品以及生物传感器等领域具有广泛的应用前景.从黑曲霉中克隆出葡萄糖氧化酶编码序列,在毕赤酵母中实现了组成型和诱导型表达并分析了其酶学性质和发酵条件.结果 表明:黑曲霉葡萄糖氧化酶的编码基因长度为1 818 bp,编码605个氨基酸,具有21个氨...