对伞花烃裂解氧化产物苯甲酸的水相酯化方法研究

对伞花烃裂解氧化产物苯甲酸与硫酸二甲酯的反应可以采用水相酯化法。实验室小试结果显示,苯甲酸的转化率平均为89.97%,苯甲酸甲酯的得率平均为83.16%;车间放大试验结果显示,苯甲酸甲酯的得率为89.00%。水相酯化法与有机相酯化法相比,甲苯的单耗降低38.69%,硫酸二甲酯的单耗下降32.14%,废水量下降35.85%,耗时减少66.67%,设备利用率和生产能力显著提高,氧化催化剂也可以得到回收。     

原子转移自由基聚合法制备聚乳酸三嵌段共聚物的研究

以自制的双端羟基聚乳酸与α-溴代丙酰溴反应而制得的含溴端基的聚乳酸为大分子引发剂,溴化亚铜/2,2′-联吡啶为催化体系,研究了N-乙烯基吡咯烷酮的原子转移自由基聚合行为,制得了具有两亲性聚乳酸嵌段共聚物。随单体/引发剂摩尔比的增大、聚合温度的升高,共聚物溶液的特性黏度增大,共聚物薄膜的吸水率增加;共聚物在不同降解介质中的降解规律相似,均随降解时间的延长,共聚物薄膜的失重增加,且在不同介质中呈现的降解速率表现为碱液>酸液>水>缓冲液。对聚合物进行了结构表征。     

活性自由基乳液聚合的研究进展

活性自由基乳液聚合是一个非常新的研究领域。介绍了目前活性自由基乳液聚合领域的3种常用的方法及应用这些方法进行乳液聚合的研究进展,包括:原子转移自由基聚合(ATRP),氮氧调节自由基聚合(NMP)和可逆加成-断裂链转移自由基聚合(RAFT)。     

羟胺催化臭氧降解邻苯二甲酸甲酯

利用硫酸羟胺（HAS）催化臭氧（O3）降解含有邻苯二甲酸二甲酯（DMP）的模拟废水,比较O3/HAS体系和O3体系中DMP的降解情况,研究了叔丁醇（TBA）和pH值对O3/HAS体系中O3分解的影响。结果表明：当pH=3.0且HAS初始浓度为20μmol/L时,反应5min后O3/HAS体系中DMP的降解率比O3体系中提高了82.58%,表明O3/HAS体系降解DMP的效率优于单独O3体系;加入TBA后O3/HAS体系对DMP的降解率显著下降,证明在O3/HAS体系中产生了羟基自由基;在pH值为3.0、7.0和9.2的条件下,O3的降解率均随着HAS浓度的升高而升高,说明HAS促进了O3的分解。此外,选择盐酸羟胺（HAC）、磷酸羟胺（HAP）催化O3降解DMP,将O3/HAS体系、O3/HAC体系、O3/HAP体系中DMP的去除效果进行对比,结果显示三种体系均可促进DMP的降解。     

高纯天然石膏水热法制备硫酸钙晶须研究

以高纯天然石膏为原料，加压水热法制备高品质硫酸钙晶须。采用常规分析方法、XRD和扫描电镜等手段分析和表征石膏原料和硫酸钙晶须产品。结果表明，制备硫酸钙晶须的最优条件为：料浆质量分数为6.0%，转晶剂氯化镁加入量为石膏质量的0.05%，硫酸加入量为水体积的1.0%，反应时间为4.0 h，快速过滤干燥即得硫酸钙晶须产品。分析结果表明：硫酸钙晶须长度最大为280.4 μm，最小为19.59 μm，平均长度为80 μm；硫酸钙晶须直径最大为5.86 μm，最小为0.20 μm，平均直径为2.67 μm；通过统计分析可知，长径比范围为10～80。     

End-capped polystyrene with 8-hydroxyquinoline group by ATRP method

8-Hydroxyqunioline end-capped polystyrene was prepared through atom transfer free radical polymerization (ATRP) with 8-(5-chloromethyl) quinolyl acetate as initiator. The results indicated that this polymerization is a first order reaction with respect to monomer conversion. The molecular weight increased linearly with monomer consumption and very narrow distribution of molecular weight was obtained (polydispersity index less than 1.2). The FT-IR and NMR results show that the 8-hydroxyquinloine group was chemically bonded to the polymer end and there is nearly one 8-hydroxyquinoline group in per polymer chain. All those data show that polymerization of styrene at such conditions displayed living characters. The polymer with 8-hydroxyqquinoline end group reacted with triethylaluminum to form polymeric light-emitting complex and single layer LED was prepared by common spin-coating method. The peak wavelength of LED based on synthesized polymeric complex was around 570 nm.     

高分子铁盐絮凝剂制备及其应用研究

研究了以废铁屑和工业硫酸亚铁为原料,在常压和加热条件下,用氯酸钾作为氧化剂制取聚合硫酸铁(PFS)的工艺条件,并在PFS制备的基础上,合成了聚磷硫酸铁(PPFS)和聚氯硫酸铁(PFCS)。将所制备的聚铁用于污水处理实验,结果表明:用该方法制备的聚铁絮凝剂对实际水样具有较好的混凝处理效果,且制备工艺简单、速度快,从根本上消除了用NaNO_2催化氧化法制备聚铁对环境造成的二次污染。     

The application of ionizing radiation in reversible addition-fragmentation chain transfer (RAFT) polymerization: Renaissance of a key synthetic and kinetic tool

Ionizing radiation, such as γ, ultraviolet, microwave and X-ray radiation, has long been used in polymer chemistry as a means of initiating polymerization, crosslinking gels and decomposing particular polymer components. More recently, ionizing radiation has found application in tandem with living radical polymerization to form novel polymeric materials with defined molecular weight and narrow molecular weight distribution. In particular, γ-rays and ultraviolet light both have shown promise as sources of initiation in reversible addition-fragmentation chain transfer (RAFT) polymerization. The ability to apply these sources of initiation at low temperatures is useful in applications where elevated temperature is likely to be detrimental to the system, for instance, in preparing protein-polymer conjugates. Similarly, the use of these initiating sources at low temperature is particularly suitable for some monomers, such as allyl compounds, which have not been synthesized using any other living radical approach. The current review examines the development of ionizing radiation as a tool in RAFT polymerization, with particular reference to the elucidation of the polymerization mechanism, the synthesis of high functionality polymers and probing the kinetic parameters of the RAFT process.     

煤中吡啶型氮热解机理的量子化学研究

用密度泛函 ( DFT)方法 ,在 UB3LYP/6- 31 G( d)水平上研究了煤中吡啶型氮的热解机理 ,对热解过程中由于官能团周围环境的不同而形成的三类吡啶自由基进行了量子化学计算 ,通过对键的 Mulliken布居数等计算结果的分析 ,分别得到了这三类自由基的热解途径 .并优化得到了反应物、中间体和产物的几何构型 .计算结果表明 ,吡啶型氮主要是以 HCN的形式释放出来的 .NH3 是 HCN二次反应的产物 .     

Radical scavenging activity of canola hull phenolics

Possible use of canola hulls as a source of natural anti-oxidants was explored. Cyclone canola hulls were extracted with methanol (30 to 80%, vol/vol) and acetone (30 to 80%, vol/vol). The free radical-scavenging activity of phenolic extracts so prepared was evaluated using the 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical ion (ABTS^o−), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, and chemiluminescence assays. The total content of phenolics in prepared extracts from canola hulls ranged from 15 to 136 mg sinapic acid equivalents per gram of extract. Higher levels of condensed tannins were detected in the acetone extracts than in the corresponding methanolic counterparts. Seventy and 80% (vol/vol) acetone extracts displayed markedly stronger antioxidant activity than any of the other extracts investigated. Statistically significant linear correlations were found between TEAC (Trolox equivalent antioxidant capacity) values (expressed in mM of Trolox equivalents per gram of extract) and total pehnolics, TEAC and total condensed tannins (i.e., determined using the modified vanillin and pronthocyanidin assays), as well as TEAC and protein precipitation activity of phenolic extracts (i.e., measured using the dye-labeled assay). The antioxidant activities of extracts as determined by the ABTS^o− radical ion assay correlated highly with those of the chemiluminescence and DPPH radical assays.