紫外分光光度法与亚甲兰分光光度法测定水中硫化物方法的对比及评价

对测定水和废水中溶解性硫化物的亚甲兰分光光度法及紫外分光光度法进行了对比性研究,并通过实际标准样品的测定,对2种测定方法在测定下限、线性范围和灵敏度及准确性等方面进行了评述,并提出了相关建议。     

On the performance of Fe and Fe,F doped Ti-Pt/PbO2 electrodes in the electrooxidation of the Blue Reactive 19 dye in simulated textile wastewater

The electrochemical performance of pure Ti–Pt/β-PbO₂ electrodes, or doped with Fe and F (together or separately), in the oxidation of simulated wastewaters containing the Blue Reactive 19 dye (BR-19), using a filter-press reactor, was investigated and then compared with that of a boron-doped diamond electrode supported on a niobium substrate (Nb/BDD). The electrooxidation of the dye simulated wastewater (volume of 0.1 l, with a BR-19 initial concentration of 25 mg l⁻¹) was carried out under the following conditions: current density of 50 mA cm⁻², volume flow rate of 2.4 l h⁻¹, temperature of 25 °C and electrode area of 5 cm². The performances of the electrodes in the dye decolorization were quite similar, achieving 100% decolorization, and in some cases 90% decolorization was achieved by applying only ca. 0.3 A h l⁻¹ (8 min of electrolysis). The reduction of the simulated wastewater organic load, monitored by its total organic carbon content (TOC), was greater for the Ti–Pt/β-PbO₂–Fe,F electrode obtained from an electrodeposition bath containing 1 mM Fe³⁺ and 30 mM F⁻. In this case, after 2 h of electrolysis the obtained TOC reduction was 95%, while for the pure β-PbO₂ and the Nb/BDD electrodes the reductions were 84% and 82%, respectively.     

Effect of blue tit song syntax on great tit territorial responsiveness – an experimental test of the character shift hypothesis

A previous study of geographic variation in blue tit (Parus caeruleus) song structure showed that changes in blue tit song syntax (i.e. presence/absence of a trill) are correlated with the breeding density of a close competitor, the great tit (P. major), and are not correlated with other environmental factors such as vegetation structure or blue tit breeding density. We tested the hypothesis that blue tit trilled song represents a character shift that evolved because it reduced territorial interactions with more dominant great tits. We conducted five sets of playback trials in three study populations (mainland southern France, Corsica and Denmark) presenting male great tits with blue tit trilled and untrilled songs and great tit songs. We found that great tits respond equally strongly to both blue tit untrilled songs and to great tit songs, but show a significantly weaker response to blue tit trilled songs. These findings are the first experimental evidence that interspecific competition may play an important role in macrogeographic variation of bird song. Received: 10 October 1999 / Received in revised form: 2 April 2000 / Accepted: 15 April 2000     

除藻剂应急治理玄武湖蓝藻水华实验研究

湖泊富营养化是中国目前及今后相当长一段时期内的重大水环境问题,研究蓝藻水华治理的关键技术具有重要的生态和环境意义.2005年9月在南京玄武湖开展了化学除藻剂治理蓝藻水华的实验研究,除藻剂平均用量为26.87 g/m2,治理后实验区藻类总量下降了82.8%;水体各项理化指标得到一定改善,但停止洒药后部分指标回升;浮游动物未出现显著变化.实验结果表明,除藻剂可能在短时间内除抑蓝藻,但不能从根本上解决湖泊富营养化问题.     

青岛在山东半岛蓝色经济区建设中的功能定位及发展对策研究

山东半岛蓝色经济区建设已正式上升为国家战略,是国家区域协调发展的重要组成部分。青岛作为山东半岛的龙头城市,综合实力强、地理位置优越、海洋资源丰富、海洋科技领先、海洋经济发达且产业结构较为合理,应借此优势将其建设成为全国蓝色经济发展的先行区、山东半岛蓝色经济区的核心区。在此过程中,青岛要进一步优化蓝色经济的空间布局,并按照“优化提升一产,发展壮大二产,突破发展三产”的思路完善产业结构。为促进山东半岛蓝色经济区快速发展,发挥辐射带动作用,青岛应营造良好的政策环境,突破海洋产业化关键技术,实施项目带动策略,加强半岛城市间的分工协作,并在开发过程中注重生态环境保护,确保蓝色经济可持续发展     

负载铁分子筛催化H2O2对活性艳蓝的脱色

以13X分子筛为载体制备负载铁催化剂,比较了经稀硫酸和氢氧化钠2种不同预处理液处理后催化剂的催化效果。利用制备的负载铁分子筛催化剂协同H2O2对活性艳蓝进行脱色研究,得出当pH=2.03,Ⅱ型催化剂投加量为4.0 g/L,过氧化氢投加量为1.1 g/L,反应时间为4 h时,脱色率最佳可达92%。     

城市蓝天保卫战行动协同控制局地大气污染物和温室气体效果评估——以唐山市为例

为满足在城市层面开展蓝天保卫战行动、协同控制局地大气污染物和温室气体效果评估的管理需求,本文构建了评估方法体系,明确了评估流程,并梳理了评估参数获取途径。本文所推荐的协同减排量核算方法和协同控制效果评估方法包括:采用排放因子法计算各措施的单项大气污染物和单项温室气体减排量,计算各措施的局地大气污染物当量(LAPeq)和二氧化碳当量(CO_2-eq)减排效果,进而采用协同控制效应坐标系分析和协同控制交叉弹性分析开展协同控制效果评估。本文以唐山市2018年蓝天保卫战行动为案例,选择12项子措施开展试点评估,结果显示:这12项子措施在减排LAPeq 13 840.89 t/a的同时,可协同减排温室气体1 009.43万t CO_2-eq/a;所评估的措施均位于协同控制效应坐标系第一象限;协同控制交叉弹性Els CO2-eq/LAPeq为6.66,即每减排1个百分点的LAPeq,可协同减排6.66个百分点的温室气体。研究表明,本文所提出的评估方法体系具有较好的适用性,可推广应用于城市蓝天保卫战行动协同控制局地大气污染物和温室气体评估工作中。     

亚甲基蓝表面修饰纳米TiO2降解造纸废水动力学

以亚甲基蓝(MB)作为表面修饰剂,采用简单的化学吸附法制备亚甲基蓝表面修饰的纳米TiO2光催化剂(TiO2-MB)。经表面修饰后,TiO2-MB光催化剂波长响应范围红移至可见光区575 nm处。探讨了光催化剂量、光照时间和溶液pH值对TiO2-MB光催化降解造纸废水的影响;研究了纳米TiO2-MB对造纸废水的暗吸附规律和光降解性能。结果表明:纳米TiO2-MB对造纸废水的吸附规律都较好地符合Langmuir和Freundlich吸附等温模型,属于吸热反应;光催化降解动力学符合Langmuir-Hinshelwood动力学模型。在160 W高压汞灯光照80 min,3.0 g/L纳米TiO2-MB光催化降解pH=2.0的造纸废水(COD:2 069.8 mg/L),COD去除率可达94.7%,处理效果远高于避光条件下。光催化剂经8次使用仍具有较高的催化活性。     

外负载Ce-TiO2/活性炭复合体对亚甲基蓝光催化

用超临界流体沉积法处理过的活性炭(AC)为载体,钛酸丁酯为前驱物,硝酸铈为掺杂剂,乙醇为溶剂,制备了外负载TiO2-Ce/Csurf复合材料。在紫外灯照射下,以亚甲基蓝溶液为标准模拟降解物,研究了复合体不同热处理温度、不同浓度、不同亚甲基蓝浓度、不同铈掺杂量以及不同反应温度对光催化性能的影响。结果表明:外负载催化剂的催化性能要高于纯TiO2和体负载催化剂。铈离子掺杂能抑制TiO2晶粒生长,阻碍了TiO2由锐钛矿型向金红石型的转变。当铈离子掺杂量为1.5%,热处理温度为600℃,亚甲基蓝溶液初始浓度为5.5 mg/L,样品浓度为1.5 g/L时,光催化性能最好。     

Forest Cover and Stream Flow in a Headwater of the Blue Nile: Complementing Observational Data Analysis with Community Perception

This study analyses the relation of forest cover and stream flow on the 266 km² Koga watershed in a headwater of Blue Nile Basin using both observed hydrological data and community perception. The watershed declined from 16% forest cover in 1957 to 1% by 1986. The hydrological record did not reveal changes in the flow regime between 1960 and 2002 despite the reduction in forest area. This agrees with the perception of the downstream community living near the gauging station. The upstream community, however, reported both decreases in low flows and increases in high flows shortly after the forest cover was reduced. The upstream deforestation effect appeared to have been buffered by a wetland lower in the watershed. This study concludes that community perception can be a complement to observational data for better understanding how forest cover influences the flow regime.