氧化还原介体催化强化污染物厌氧降解研究进展

 由于厌氧生物处理技术具有产生剩余污泥少、可回收能源等优点而被广泛用于处理各种有机污染物，尤其在有毒、有害、难降解污染物的去除方面取得了良好的效果。然而，厌氧生物法的处理速率通常比较低，而氧化还原介体可通过自身不断的氧化和还原来传递电子，提高电子在氧化还原反应过程中的传递速率，从而促进污染物高效厌氧降解。醌类物质和腐殖酸是应用较多的氧化还原介体，在催化难降解污染物降解方面取得了一定效果。讨论了氧化还原介体的特点、作用机制，并总结了其对偶氮染料厌氧脱色、反硝化和多氯联苯厌氧降解的强化作用，提出了氧化还原介体未来的研究方向。     

湖南山丘区景观生态系统退化特征初探

湖南山地丘陵面积约占全省土地总面积的２／３，是省域最重要的景观生态系统类型。自然状态下，湖南山丘区景观生态系统中景观组分性质优良，景观要素组合协调，景观生态过程稳定，景观功能较强。然而，在长期的人类活动影响之下，湖南山丘区景观生态系统显现出明显的退化特征，具有表现为景观要素组合关系改变、景观组分性质劣化、景观生态过程逆转、景观生态系统抗性降低。     

AgCl膜光催化降解色素的研究

利用AgCl膜在不同波长光照条件下对水溶液中的5种有机色素进行催化降解实验．实验结果表明，30min内，5种色素(质量浓度为20mg/L)均得到迅速光解，且在太阳光光照条件下AgCl膜具有非常高的光催化性能．并进一步研究了成膜原料液的浓度对光解率的影响、溶液初始质量浓度与光解速率的关系及悬浮态AgCl的光催化对比实验．     

Coastal wetland in South China： Degradation trends, causes and protection countermeasures

There are abundant coastal wetlands in South China and their main characters are the tidal flats, mangroves and coral reefs. In this paper, the status quo of coastal wetlands in South China is introduced and their degradation trends in the last decades are analyzed based on the existing literatures and information. Their degradation trends are characterized by reduction of coastal wetlands＇ area, pollution of seawater environment, degeneration of ecological environment, sharp decrease of biodiversity in the wetlands and so on. At the same time, the causes resulting in the above-mentioned degradations are discussed, mainly concluding imperfect systems of management and legislation, deficient property and assessment systems of the wetlands, weak consciousness of protecting coastal wetlands, shortage of basic study and backward management level and so on. Some countermeasures are put forward for the sake of a sustainable use of the coastal wetlands of South China, mainly including establishing and perfecting administrative and legal systems for the coastal wetlands, developing the study on assessment of coastal wetland, heightening the consciousness of public participation, and strengthening scientific research and establishment of wetland nature reserves.     

AFM对壳聚糖富集银离子的分形学研究

利用原子力显微镜(AFM)对壳聚糖吸附银离子进行研究，从形貌学的角度探测壳聚糖络合银离子的机理特性．主要方法是将溶液滴加在新解离的云母片上，应用原子力显微镜对自然风干后的样品在非接触模式下成像．AFM图像显示：壳聚糖分子和加过金属银离子的壳聚糖分子在聚集生长过程呈现为传统的具有分形特征的正态分布和奇异分布；由单一的壳聚糖分子形成的分形结构为“星”形结构，而加过银离子的壳聚糖分子形成的结构为“圆”形．产生这些图形差别的根本原因是由于生长界面的表面张力及其各向异性起了重要作用．这两种结构都具有典型的自相似性，且实验结果与计算机模拟的分形模式拟合得很好．     

微波辐射法制备环境友好型絮凝剂

主要研究了在微波处理条件下由虾、蟹壳制备环境友好型絮凝剂的方法。并对各因素对甲壳素脱乙酰度的影响进行了讨论,用正交试验确定了最优的反应条件。     

分子筛负载HPA/TiO2催化剂的性能

报道了分子筛负载杂多酸和二氧化钛催化剂MS／HPA／TiO2的制备及其对品红溶液降解的效果，系统研究了催化品红溶液降解的优化条件。实验表明，MS／HPA／TiO2具有良好的催化活性且容易回收。当MS：HPA：TiO2=1：10：1，品红的浓度为0．005％（10mL），催化剂的用量为10mg，反应时间为10min，品红的降解率达到96．87％。     

Autophagy and other vacuolar protein degradation mechanisms

Autophagic degradation of cytoplasm (including protein, RNA etc.) is a non-selective bulk process, as indicated by ultrastructural evidence and by the similarity in autophagic sequestration rates of various cytosolic enzymes with different half-lives. The initial autophagic sequestration step, performed by a poorly-characterized organelle called a phagophore, is subject tofeedback inhibition by purines and amino acids, the effect of the latter being potentiated by insulin and antagonized by glucagon. Epinephrine and other adrenergic agonists inhibit autophagic sequestration through a prazosin-sensitive ₁-adrenergic mechanism. The sequestration is also inhibited by cAMP and by protein phosphorylation as indicated by the effects of cyclic nucleotide analogues, phosphodiesterase inhibitors and okadaic acid.Asparagine specifically inhibits autophagic-lysosomal fusion without having any significant effects on autophagic sequestration, on intralysosomal degradation or on the endocytic pathway. Autophaged material that accumulates in prelysosomal vacuoles in the presence of asparagine is accessible to endocytosed enzymes, revealing the existence of an amphifunctional organelle, the amphisome. Evidence from several cell types suggests that endocytosis may be coupled to autophagy to a variable extent, and that the amphisome may play a central role as a collecting station for material destined for lysosomal degradation.Protein degradation can also take place in a salvage compartment closely associated with the endoplasmic reticulum (ER). In this compartment unassembled protein chains are degraded by uncharacterized proteinases, while resident proteins roturn to the ER and assembled secretory and membrane proteins proceed through the Golgi apparatus. In thetrans-Golgi network some proteins are proteolytically processed by Ca²⁺-dependent proteinases; furthermore, this compartment sorts proteins to lysosomes, various membrane domains, endosomes or secretory vesicles/granules. Processing of both endogenous and exogenous proteins can occurr in endosomes, which may play a particularly important role in antigen processing and presentation. Proteins in endosomes or secretory compartments can either be exocytosed, or channeled to lysosomes for degradation. The switch mechanisms which decide between these options are subject to bioregulation by external agents (hormones and growth factors), and may play an important role in the control of protein uptake and secretion.     

胍基化壳聚糖季铵盐的制备及其抗菌性能

以三聚氯氰(TCT)为中间桥梁,将聚六亚甲基双胍(PHMB)接枝到N-(2-羟丙基-3-甲基氯化铵)壳聚糖(HTCC)上,制备胍基壳聚糖季铵盐(HCP).研究制备HCP的最佳反应条件,采用元素分析、傅里叶变换红外光谱(FTIR)和核磁共振氢谱(¹H NMR)对产物的结构进行表征,并测试其抗菌性能.得到HCP的最佳反应条件为HTCC和TCT的摩尔比1.0∶2.5,HTCC和PHMB的质量比1.0∶1.2,缚酸剂为三乙胺,TCT一取代的反应时间8 h,二取代的反应时间14 h,反应温度40℃.结果表明：制得的HCP对大肠杆菌(E.coli)和金黄色葡萄球菌(S.aureus)的最低抑菌质量浓度分别为0.020,0.005 mg·mL^-1;质量浓度为1.0 mg·mL^-1的HCP对E.coli和S.aureus的抑菌率分别为89.8%和100.0%,高于相同质量浓度下HTCC对E.coli和S.aureus的抑菌率18.2%和18.7%.