氮掺杂氧化钛的简易制备及可见光催化活性的研究

为开发对可见光响应的催化剂,以尿素为氮掺杂剂,采用简易溶胶-凝胶法制备氮掺杂氧化钛,并以2,4-DCP的降解检验其光催化活性。XRD、BET、XPS和UV-Vis漫反射光谱分析表明,随着氮/钛原子比（N/Ti)的增大,各催化剂晶粒尺寸减小,比表面积增大,锐钛矿相向金红石相的转变得到抑制,除0#样品出现金红石相外,其他催化剂均只出现锐钛矿相;掺入催化剂的N位于晶格O位点和晶格间隙,替代N和间隙N掺杂使催化剂的光吸收发生明显的红移。荧光光谱分析表明,当N/Ti在0～6范围内增加时,反应体系中·OH自由基的产生速率增加,当N/Ti增大至8时,速率则下降。相似的规律也表现在氮掺杂量对光催化活性的影响。适量氮掺杂能增强氧化钛的可见光催化活性,该改性催化剂可用于有机污染物的太阳光激催化降解。     

应用CALINE4模式估算机动车排放污染物的浓度——以济南市主干道为例

随着经济的快速发展,机动车排气污染已成为我国城市空气污染的重要来源,而且在一定时段,机动车排气污染已成为空气污染最主要的污染源之一。以济南市经十路为例,采用实地调查的方法,得出各时段的车流量,选用大气环评助手EIAA中的CALINE4模式对机动车尾气中的主要污染物CO、NOx、THC的排放浓度进行估算,得出3种污染物CO、NOx、THC最大值均出现在7:00—8:00之间,最小值均出现在12:00-13:00之间,排放强度由大到小为:CO、THC、NOx。     

大连市中心区O3污染特征分析

本文采用2007年大连市环境自动监测数据,分析了城市中心区O3的污染特征。结果表明：O3质量浓度的最大值出现在午后15：00—17：00,比太阳辐射强度最大值的出现时间滞后2h左右;O3质量浓度的季节性变化十分显著,春夏季较高,秋季次之,冬季最低;汽车尾气是近地面O3污染的主要原因。     

镰刀菌HJ01对对氯苯酚的降解特性

采用实验室分离的一株镰刀菌HJ01,以对氯苯酚(4-CP)为降解底物,以蔗糖为外加碳源,考察了蔗糖质量浓度、降解温度、初始pH对4-CP降解效果的影响,初步探讨了镰刀菌HJ01对4-CP的降解动力学和降解机理.实验结果表明:该菌株能以4-CP为惟一碳源和能源生长;在外加蔗糖为碳源,蔗糖质量浓度为3 g/L、降解温度为30℃、初始pH为8的条件下,50 mg/L4-CP能在6 d内被完全降解.以4-CP为惟一碳源和外加蔗糖下的降解动力学分别符合Haldane模型和一级动力学方程.     

5—(4—磺酸基苯偶氮)8—(2,4—二硝基苯氨基)喹啉测定食品中铜的研究应用

在弱碱性介质中 ,5— (4—磺酸基苯偶氮 ) 8— (2 ,4—二硝基苯氨基 )喹啉 (SPDNPAQ)与铜反应生成 2∶ 1紫红色络合物 ,体系 λmax=56 0 nm,ε=1.2 3× 10 5L· mol-1· cm-1。铜含量在 0～ 0 .4 mg/ L内符合比耳定律 ,方法用于一些生物样品和水样中铜的测定。     

橡胶促进剂M盐废水生物处理技术研究

为探讨微生物技术在橡胶促进剂M盐废水处理中的应用,利用高效优势蘸强化A2O工艺对橡胶促进剂M盐废水进行处理,整个系统运行过程分为污泥的培养与驯化阶段及稳定运行阶段。在稳定运行阶段COD0平均去除率达90．71％,氨氮平均去除率达78．31％。以Mn^2＋、Fe^2＋、Mg^2＋、Ni^2＋为4个影响因子,通过正交实验分析无机离子对橡胶促进剂M盐废水中有机物降解的促进作用。由实验数据的摄差大小可知,各无机离子对优势复合菌降解橡胶有机废水的影响从大到小依次为：Mn^2＋、Fe^2＋、Ni^2＋和Mg^2＋。4种离子最佳质量浓度组合为：0．500mg／L的Mn^2＋、1．00mg／L的Fe^2＋、35．0mg／L的Mg^2＋和0．025mg／L的Ni^2＋。     

气体二氧化氯对葡萄表面细菌杀菌规律研究

研究气体二氧化氯杀灭金黄色葡萄球菌、大肠杆菌、李斯特单增菌和腐生酵母菌4种葡萄表面的危险致病菌的杀菌规律。在实验范围内,随着气体二氧化氯浓度的增加和杀菌时间的延长,杀菌效果明显增加。当杀菌时间超过12min,杀菌量级几乎不再增加。杀菌效率随温度的增加而减小,在实验温度条件下,只有大肠杆菌的杀菌效果减少了5.38～6.09log量级,其他3种菌均减少了6log量级以上,杀菌作用温度在实验条件下对杀菌效果影响不大。研究表明,当气体二氧化氯的杀菌浓度为25mgl-1、杀菌时间12min、杀菌温度25℃的条件下,金黄色葡萄球菌、李斯特单增菌和腐生酵母菌均减少了6.4log量级以上,而大肠杆菌达到5.76log量级;同时表明二氧化氯气体的杀菌保鲜功能也是食品安全技术非热杀菌手段。     

Mining and social development: Refocusing community investment using multi-criteria decision analysis

This paper addresses the question: How can mining companies assess social investment projects so that projects create value for the company and communities in which they operate? Mining companies are still wrestling with the limits of their responsibility in relation to social development even though they accept the business case for community investment at a general level. Fully aware of the practical hazards involved in taking an active role in facilitating local development, companies increasingly avoid methods that are overly paternalistic or assume the functions of the national or local governments. Gaining senior management's commitment to long-term social projects, which are characterised by uncertainty and complexity, is made easier if projects are shown to benefit the site's strategic goals. Case study research on large global mining companies, including interviews with social investment decision makers, has assisted in developing a Social Investment Decision Analysis Tool (SIDAT), a decision model for evaluating social projects. Multi-criteria decision analysis techniques integrating business planning processes with social impact assessment have proved useful in assisting mining companies think beyond seeking reputational benefits, to how they can meet their business goals and contribute to sustainable development.     

Natural resource abundance in Nigeria: From dependence to development

There are several strategies open to an economy in its attempt to attain sustainable economic development depending on its historical background and resource endowment. One of such is the resource-led strategy. Nigeria is superabundantly rich in crude oil and has reaped billions of petrodollars. However, the country seems to be facing the problem of successfully translating this huge oil wealth into sustainable development. This paper employs the vector error-correction methodology in examining the long-run impact of the huge oil wealth accruing to Nigeria on its economic development. Indicators such as per capita GDP (PGDP), household consumption, infrastructural development (electricity), and agricultural and manufacturing output growth rates are examined. The results suggest a significant positive long-run impact of per capita oil revenue on per capita household consumption and electricity generation, while a negative relationship is established for GDP, agriculture and manufacturing. Even for those variables with negative relationship at current period, there exist positive relationships at subsequent lags. Thus, oil revenue, if properly managed and invested, could be effectively used to induce oil-led development in Nigeria provided the current inhibitions of corruption, lack of transparency, accountability and fairness in its use and distribution are removed.     

Relationships between anaerobic consortia and removal efficiencies in an UASB reactor degrading 2,4 dichlorophenol (DCP)

To gain more insight into the interactions between anaerobic bacteria and reactor performances (chemical oxygen demand-COD, 2,4 dichlorophenol-2,4 DCP removals, volatile fatty acid-VFA, and methane gas productions) and how they depended on operational conditions the microbial variations in the anaerobic granular sludge from an upflow anaerobic sludge blanket (UASB) reactor treating 2,4 DCP was studied. The study was composed of two parts. In the first part, the numbers of methanogens and acedogens in the anaerobic granular sludge were counted at different COD removal efficiencies. The relationships between the numbers of methanogens, the methane gas production and VFA production were investigated. The COD removal efficiencies increased to 74% from 30% while the number of total acedogens decreased to 10 from 30 cfu ml(-1). The number of total methanogens and acedogens varied between 11 x 10(3) and 10 x 10(9)MPN g(-1) and 10 and 30 cfu ml(-1) as the 2,4 DCP removal efficiencies were obtained between 60% and 99%, respectively. It was seen that, as the number of total acedogens decreased, the COD removal efficiencies increased. However, the number of total methanogens increased as the COD removal efficiencies increased. Correlations between the bacterial number and with the removal efficiencies obtained in different operational conditions were investigated. From the results presented in this paper a high correlation between the number of bacteria, COD removals, methane gas percentage, 2,4 DCP removals and VFA was observed. In the second part, methanogen bacteria in the anaerobic granular sludge were identified. Microbial observations and biochemical tests were applied to identify the anaerobic microorganisms from the anaerobic granular sludge. In the reactor treating 2,4 DCP, Methanobacterium bryantii, Methanobacterium formicicum, Methanobrevibacter smithii, Methanococcus voltae, Methanosarcina mazei, Methanosarcina acetivorans, Methanogenium bourgense and Methanospirillum hungatei were identified.