TiO2/N可见光光催化降解邻苯二甲酸二甲酯

采用氮掺杂的二氧化钛为催化剂,探索了可见光催化氧化降解邻苯二甲酸二甲酯(DMP)的研究.系统地考察了光催化降解反应中DMP的初始浓度、光照时间、催化剂的量、pH值等因素对邻苯二甲酸二甲酯(DMP)的降解效率及速率的影响;同时对其光降解动力学及光降解过程中的矿化程度进行了一定的分析.结果表明,只有在催化剂和光源同时存在的情况下,DMP才有比较好的降解效果.当DMP的初始浓度为10 mg/L时,在优化条件下,即光催化剂为量1 g/L,pH值为6.20时,在以500W氙灯下进行光照8h,其降解率可达到90%以上.此光催化降解反应过程符合一级反应动力学.     

UV/Fenton法处理水中苯酚的研究

通过大量试验，确定了UV/Fenton法处理水中苯酚的最佳条件。pH为3.0，[H     

叉车内燃机润滑油变质趋势分析

利用铁谱分析技术结合部分理化指标，通过对数台叉车内燃机的系统跟踪监测，给出了实际工况下内燃机在用润滑油变质趋势图，据此拟合出了数学模型，并对这种变化趋势的形成作了较为深入地理论探讨对于严格控制和判断润滑油质量的变化程度以及润滑油的更换期都有着指导意义，同时为开发新型润滑油提供了一种可行的检测方法     

高浓度丙烯腈废水的辐照处理

为考察优先污染物丙烯腈在γ辐照下的去除情况,选取了高浓度的丙烯腈废水作为研究对象,利用60Co作为γ射线源进行辐照分解,并利用吡啶比色法测定水中丙烯腈的含量,研究了丙烯腈的辐照降解。结果表明:辐照剂量为15kGy时,丙烯腈去除率随初始浓度的增大而增大;初始质量浓度为4g/L的丙烯腈溶液,随着辐照剂量的增大,丙烯腈的去除率先增加后减小,10 kGy时的去除效果最佳,去除率达到90%以上;在中性条件下的去除效果要好于偏酸或偏碱性条件;添加FeCl3对丙烯腈去除率的影响很小。     

用钌离子催化氧化法研究干酷根及其显微组分的化学结构

用钌离子选择性催化氧化法研究了茂名油面岩士酪根、山西蒲县藻煤藻类体、长广树皮煤的树此体以及山西繁峙褐煤镜质组的化学结构。研究结果表明，茂名油面岩干酷根和蒲县藻煤藻类体的化学结构均以醚／酸键形式交联的中等链长的脂链结构为主，繁峙褐煤镜质组中的芳 结构仍保留着木质素基本结构单元的单环结构，同时含有丰富的脂族化合物。这些脂族化全物可能来自这一富氢显微组分中的超微类脂体。长广树皮煤中树皮体以少于４个环的稠     

a-Si/CuInSe2叠层太阳能电池中的空间电荷效应

基于ｐｉｎ结构的ａ－Ｓｉ：Ｈ太阳能电池中的空间电荷效应，讨论了ａ－Ｓｉ／ＣｕＩｎＳｅ２叠层太阳能电池的稳定性。采用计算机数值模拟方法，得出由光生空穴俘获产生的ａ－Ｓｉ：Ｈ层中正空间电荷密度的增加，改变了电池内部的电场分布，普遍抬高了ａ－Ｓｉ：Ｈ薄膜中的电场强度；在当照射下，空间电荷效应不会给ａ－Ｓｉ／ＣｕＩｎＳｅ２叠层结构中的ａ－Ｓｉ：Ｈ薄膜中的场强度；在光照射下，空间电荷效应不绘给ａ－Ｓｉ／Ｃｕ     

Evaluation of cement degradation induced by the metabolic products of two fungal strains

Summary During their metabolism, microorganisms can produce acids able to bring about the degradation of cement. Two acid-producing alkalophilic fungal strains have been isolated from soil, a strain ofAspergillus niger which produces gluconic and oxalic acid and ofMycelia sterila which produces gluconic and malic acid. After eleven months of contact the acids produced byAspergillus dissolved portlandite with a low leaching of calcium, increased the cement porosity by 11.4%, and reduced the bending strength by 78%. The second strain is responsible for a significant dissolution of portlandite with a leaching of calcium of 4.2% of the initial content, an increase of the porosity of 11%, and a loss of the bending strength of 62%. Direct contact of mycelia with the cement surface is not necessary for effective dissolution to take place. Low pH and a high temperature favor the the production of acids.     

亚甲蓝光敏反应对癌细胞蛋白质及DNA的影响

不同浓度（０．０３８，０．３８，３．８０μｍｏｌ／Ｌ）的亚甲蓝光敏反应，对腹水型肝癌细胞（ＨｅｐＡ）蛋白质及ＤＮＡ分子具有明显的降解作用，并随亚甲蓝浓度的增加而加剧，而过氧化氢酶对细胞有明显的保护作用，说明亚甲蓝光敏反应与Ｈ２Ｏ２密切相关。     

Keratinase production and keratin degradation by a mutant strain of Bacillus subtilis

A new feather-degrading bacterium was isolated from a local feather waste site and identified as Bacillus subtilis based on morphological, physiochemical, and phylogenetic characteristics. Screening for mutants with elevated keratinolytic activity using N-methyl-N＇-nitro-N-nitrosoguanidine mutagenesis resulted in a mutant strain KD-N2 producing keratinolytic activity about 2.5 times that of the wild-type strain. The mutant strain produced inducible keratinase in different substrates of feathers, hair, wool and silk under submerged cultivation. Scanning electron microscopy studies showed the degradation of feathers, hair and silk by the keratinase. The optimal conditions for keratinase production include initial pH of 7.5, inoculum size of 2% （v/v）, age of inoculum of 16 h, and cultivation at 23 ℃. The maximum keratinolytic activity of KD-N2 was achieved after 30 h. Essential amino acids like threonine, valine, methionine as well as ammonia were produced when feathers were used as substrates. Strain KD-N2, therefore, shows great promise of finding potential applications in keratin hydrolysis and keratinase production.     

N-Monomethyl-arginine and nicotinamide prevent streptozotocin-induced double strand DNA break formation in pancreatic rat islets

The impact of short term in vitro exposure to the diabetogenic drug streptozotocin on pancreatic islet glucose metabolism, insulin secretion, DNA fragmentation and cell viability, was studied. Streptozotocin impaired cell viability as well as insulin secretion and the oxidation of glucose. These effects were partially counteracted by inhibition of the inducible form of nitric oxide synthase with N-monomethyl-arginine and by scavenging oxygen free radicals with nicotinamide. Isolated islets underwent double strand DNA fragmentation after 24 h in culture. The degree of DNA breakdown was strongly enhanced by exposure of the islet DNA was obtained with N-monomethyl-arginine and nicotinamide. These data suggest that the generation of reactive oxygen and nitrogen species is involved in the deleterious action of streptozotocin on pancreatic islet tissue. A role for oxygen radicals generated during streptozotocin-induced islet cell damage as possible mediators of the expression of the inducible form of nitric oxide synthase and the scavenging action of nicotinamide on these radicals, is then proposed.