湿法腈纶生产的含腈废水处理实验研究

采用不同方法对湿法腈纶废水进行预处理，比较了它们的处理效果和特点。研究中使用的菌种预处理方法达到了理想的效果，废水中大分子有机污染物被迅速、高效地分解为挥发性脂肪酸和氨氮等，为后续的接触氧化以及反硝化创造了良好的条件，COD和TKN的总去除率分别为92％和85％，最终出水达到或优于行业二级排放标准。     

Ozonolysis of polybutadienes with different microstructure in solution

The reaction of ozone with 1,4‐cis‐polybutadiene and polybutadiene having the following linking of the butadiene units: 1,4‐cis (47%), 1,4‐trans (42%), 1,2 (11%) was investigated in CCl₄ solution. It was found out by means of IR‐spectroscopy and ¹H‐NMR spectroscopy that the basic ozonolysis products of both elastomers are ozonides and aldehydes. The aldehyde:ozonide ratio was 11 : 89 and 27 : 73 for E‐BR and BR, respectively. In addition, epoxide groups were detected, only in the case of BR, and their yield was about 10% of that of the aldehydes. On the basis of BR ozonolysis it was established that the ozonide yield from 1,4‐trans units is about 50%. By using the aldehyde yields, an evaluation was made of the efficiency of ozone degradation of the two polybutadienes, according to which the respective value of BR is considerably higher than that of E‐BR. A reaction mechanism is proposed, which explains the formation of the identified functional groups and the differences in the ozone degradation of the studied elastomers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 427–433, 2007     

4BS染料光催化降解动力学

在间歇式淤浆床反应器中 ,以TiO₂ 为催化剂、高压汞灯为光源进行了 4BS染料光催化降解的动力学研究 .通过改变催化剂用量、反应时间及反应物初始浓度等条件 ,确定适宜的催化剂用量和溶液的 pH值 .在此基础上得到了消除固液混合及外扩散影响后的反应动力学方程 ,为反应器设计提供了必要的理论依据 .     

异相结/异质结TiO2光催化机理及降解有机物的研究

到目前为止TiO2是较为成熟的半导体光催化材料，但因TiO2分散性差、量子利用率低、比表面积小、难回收等问题难以工业化。多孔金属有机框架MOFs的引入可增强TiO2/MOFs复合材料的光吸收性能，提高电子-空穴对分离和提高回收率。基于TiO2/MOFs制备时前驱体添加顺序不同，综述了TiO2/MOFs的三种制备方法（即Ship-in-a-bottle法、Bottle-around-ship法、One-pot法）及TiO2/MOFs光催化机理与性能影响因素，并探讨不同MOFs与TiO2结合的作用机理。最后，对TiO2/MOFs存在的问题提出建议。     

微生物降解原油发酵液中低分子量有机酸的测定

本文使用气-质联用仪对微生物降解原油发酵液中低分子量有机酸进行测定。采用水蒸汽蒸发法蒸出发酵液中低分子量有机酸，从而使其与样品中大量的无机盐和表面活性剂分离，浓缩后直接进样。该方法简单直接，可以减少有机酸的损失。     

Aging behavior of a hot‐cured epoxy system

The thermal and hydro‐thermal aging of a hot‐cured epoxy system (diglycidylether of bisphenol A (DGEBA) + dicyandiamide (DDA)) in the glassy state is revisited using DSC and IR attenuated total reflection spectroscopy. Because of the diffusion of DDA from the solid particles into the liquid DGEBA matrix, curing produces a highly crosslinked amorphous matrix that contains low crosslinked amorphous regions. After full curing, the network possesses a relatively low molecular mobility and no residual reactive groups. Thermal and hydro‐thermal loading is performed at 60°C, well below the principal glass transition temperature (T_g1 = 171°C). Both aging regimes cause significant chemical and structural changes to the glassy epoxy. It undergoes a phase separation of relatively mobile segments inside the low mobile matrix, providing a second glass transition that shifts from T_g2 = 86–114°C within 108 days of aging. This phase separation is reversible on heating into the viscoelastic state. Hydro‐thermal aging leads to a reversible and a nonreversible plasticizing effect as well. On thermal aging, no chemical changes are observed but hydro‐thermal aging causes significant chemical modifications in the epoxy system. These modifications are identified as a partial degradation of crosslinks produced by the cyano groups of the DDA and correspond to the nonreversible plasticitation. These changes in the cured epoxy should exert an influence on the mechanical properties of an adhesive bond. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

纤维素科学与技术研究进展

本文综述纤维素科学与技术的研究进展。阐述了纤维素结构、纤维素的合成、纤维素液晶、功能纤维素、纤维素溶剂、纤维素裂解和纤维素的废物利用等的最新动态。     

Enzymatic degradation of thermoresponsive poly(N‐isopropylacrylamide) grafted to carboxymethylcellulose copolymers

The enzymatic degradation of poly(N‐isopropyl acrylamide) (PNIPAM) grafted to carboxymethylcellulose (CMC) copolymers with a cellulasic preparation (Trichoderma viride) was studied. The enzymatic activity of the cellulasic preparation against CMC and the grafted copolymers was determined by the Petterson–Porath method, while their reduced viscosity variation in the presence of the same preparation was also followed. It has been shown that the enzymatic degradation behavior depends on the copolymer composition and the reaction temperature. Reducing sugars analysis showed that the experimental values for the grafted copolymers were higher than the calculated ones. At 50°C, the enzymatic reaction is completed in about 20 min for the copolymers, whereas for CMC it takes more than 40 min. It can be concluded that their enzymatic degradation is facilitated by the presence of the PNIPAM grafts. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1383–1386, 2003     

Fe掺杂A-TiO_2在溴甲酚绿中的可见光催化活性及动力学

以FeCl_3·6H_2O为Fe源,采用水热法制备了Fe掺杂锐钛型TiO_2(A-Ti O2)光催化剂。以溴甲酚绿为降解对象,考察溴甲酚绿的初始浓度、催化剂用量、掺Fe量等因素对自制催化剂可见光催化降解反应的动力学方程的影响。结果表明:在40 W白炽灯照射下,当溴甲酚绿初始浓度为10 mg/L(pH=7)、催化剂的用量为0.6 g/L、掺Fe量为4%(摩尔分数)、室温下反应时间为3 h时,溴甲酚绿的降解率最大为76.05%。溴甲酚绿光催化降解曲线符合一级反应动力学方程,于上述最佳条件下其表观反应速率常数k达到最大值,为0.389 7 h-1。     

Zr掺杂g-C3N4光催化降解有机污染物

以盐酸胍为前驱体，硝酸锆为锆源，通过热聚合法制备了Zr掺杂的Zr/g-C3N4光催化剂。运用XRD、SEM、UV-Vis DRS、PL、XPS、BET等手段对催化剂的结构、形貌、光学性能进行了表征分析。结果表明：Zr掺杂改性的Zr/g-C3N4光催化剂拓宽了可见光的吸收，增大了比表面积，且降低了光生电子-空穴的复合率，具有较好的光催化活性。可见光照射下，在60 min内，5Zr/g-C3N4对罗丹明B（RhB）的光催化降解率达99.29%，光催化降解过程符合一级动力学方程，其速率常数k= 0.08647 min-1，是纯g-C3N4的8.3倍。捕获剂实验发现降解RhB的主要活性物种为超氧自由基，并推测了可能的反应机理。