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1.
研究以平玻璃和毛玻璃为载体,用Sol gel法制备附载型TiO2/Glass光催化剂,并用H2SO4溶液浸泡制得TiO2 SO2-4/Glass光催化剂。考察了光催化剂对甲基橙溶液的光催化性能。结果表明:平玻璃附载TiO2的光催化活性低于毛玻璃附载TiO2的光催化活性。且毛玻璃附载TiO2经连续6次使用后光催化活性基本不变。毛玻璃附载TiO2经H2SO4溶液处理后光催化活性明显升高。  相似文献   

2.
研究以平玻璃和毛玻璃为载体,用Sol-gel法制备附载型TiO2/G1ass光催化剂,并用H2SO4溶液浸泡制得TiO2-SO4^2-/Glass光催化剂。考察了光催化剂对甲基橙溶液的光催化性能。结果表明:平玻璃附载TiO2的光催化活性低于毛玻璃附载TiO2的兆催化活性。且毛玻璃附载TiO2经连续6次使用后光催化活性基本不变。毛玻璃附载TiO2经H2SO4溶液处理后光催化活性明显升高。  相似文献   

3.
玻璃纤维附载TiO2光催化降解有机磷农药   总被引:103,自引:3,他引:100  
研究以四异丙醇钛为原料,配制成胶体用玻璃纤维附载TiO2的过程;同时利用附载的TiO2光催化降解有机磷农药。结果表明,低浓度的4种有机磷农药,375W中 汞灯短时间照射有机磷将完全被光催化氧化至PO^3-4;玻璃纤维上附载的TiO2不易脱落。  相似文献   

4.
附载TiO2光催化降解咪蚜胺农药   总被引:17,自引:0,他引:17  
以主波长365nm的黑炽荧光灯为光源,研究了由CMC-Na附载TiO2光催化降解咪蚜胺农药的过程。结果表明,咪蚜胺农药在3*8W黑炽荧光灯照射下,经附载TiO2作用3h后可降解50%以上,其光解可用假一级动力学方程表示。  相似文献   

5.
研究以四异丙醇钛 [Ti(iso OC3H7) 4]、异丙醇铝为原料 ,以空心玻璃微球为载体 ,用溶胶 -凝胶法制备可漂浮附载型复合光催化剂TiO2·Al2 O3/beads的过程。用该光催化剂降解有机磷农药 ,并与光催化剂DegussaP 2 5TiO2 光活性进行比较。结果表明 ,附载型复合光催化剂活性显著提高 ,最高光活性为同样降解条件下 ,同样含量DegussaP 2 5TiO2 光活性的 1.4倍 ,且TiO2 ·Al2 O3 组分摩尔比存在最佳值。同时还研究了TiO2 ·Al2 O3/beads对有机磷农药的吸附性 ,并用XRD和TEM对附载型复合光催化剂进行表征。  相似文献   

6.
附载型复合光催化剂TiO2.Al2O3/beads降解有机磷农药   总被引:7,自引:0,他引:7  
研究以四异丙醇钛[Ti(iso-OC3H7)4]、异丙醇铝为原料,以空心玻璃微球为载体,用溶胶-凝胶法制备可漂浮附载型复合光催化剂TiO2.Al2O3/beads的过程。用该光催化剂降解有机磷农药,并与光催化剂DegussaP-25TiO2光活性进行比较。结果表明,附载型复合光催化剂活性显著提高,最高光活性为同样降解条件下,同样含量DegussaP-25TiO2光活性的1.4倍,且TiO2.Al2O3组分摩尔比存在最佳值。同时还研究了TiO2.Al2O3/beads对有机磷农药的吸附性,并用XRD和TEM对附载型复合光催化剂进行表征。   相似文献   

7.
新型纳米材料光催化反应器研究   总被引:1,自引:0,他引:1  
为了充分发挥纳米材料的光催化性能,研制了一种带有旋转叶片且可负载光催化纳米材料的光催化反应器.并以制备的纳米TiO2/硅藻土复合材料作为光催化剂、TNT生产废水为处理对象,考察了催化材料附载量、废水浓度和多次重复使用对反应器催化降解效率的影响.结果表明:附载有光催化纳米材料的反应器经过6次6h重复使用,对TNT生产废水催化降解效率仍然保持在75%以上,远高于直接分散在废水中纳米材料的处理效率(47.25%),即多次重复使用并保持高降解效率;而且可较好地避免纳米光催化材料的团聚.避免因回收造成的纳米材料光催化效率降低以及回收不完全造成的水体二次污染等现象.  相似文献   

8.
金属铁还原降解2,4-二硝基甲苯的实验研究   总被引:1,自引:0,他引:1  
研究了金属铁对2,4-二硝基甲苯(2,4-DNT)的还原降解情况.实验结果表明,2,4-DNT的还原降解与溶液初始pH值、初始浓度和溶解氧等因素有关.氯离子能消除金属铁的钝化现象.金属铁表面附载的铜对2,4-DNT的还原降解具有催化作用.  相似文献   

9.
附载型二氧化钛光电催化降解苯胺机理   总被引:28,自引:4,他引:28  
以附载在镍网上的TiO2为催化剂,研究了水中苯胺光电降解行为和机理.结果表明在有氧存在时光催化能有效降解苯胺.苯胺为1.89×10-4mol/L时,其量子产率为8.12%.缺氧时,光反应不能进行,但外加阳极偏压能使光催化反应进行并能大大提高苯胺的降解速率.通过GC-MS技术确定其降解中间产物主要有硝基苯和偶氮苯等,它们可最终矿化为NH+-4、NO+-3和CO2.  相似文献   

10.
附载型吸附剂对煤油中硫醇类硫的吸附特性   总被引:4,自引:0,他引:4  
利用浸渍-焙烧法制备的载有铜、铅或锰的附载型吸附剂吸附煤油中的硫醇类硫,脱硫醇效果显著。制备的各种吸附剂吸附硫醇类硫的过程中的液膜扩散,颗粒内部的扩散性存在差异。等温吸附曲线显示载铜氧化铝吸附剂对硫醇的吸附遵从Langmuir方程,载铅氧化铝吸附剂对硫醇的吸附可用Freundlich方程拟合。流量为每小时1个床体积的固体床动态吸附结果表明,载铅氧化铝吸附剂吸附过程到达穿透点(硫醇类硫浓度为2.55mg/L)的连续过液量为97个床体积。  相似文献   

11.
广州流溪河水库叶绿素a遥感反演研究   总被引:1,自引:0,他引:1  
叶绿素a是衡量水体初级生产力和富营养化程度的一项重要指标。本研究在讨论分析反演水体叶绿素a浓度的半分析生物光学模型理论基础上,利用Landsat TM数据及中巴资源卫星02星CCD相机高分辨率数据,结合实测数据建立广州流溪河水库叶绿素a浓度的波段比值型反演模型。该模型对两个不同监测日期的叶绿素a浓度反演效果较好,拟合系数(R2)分别达到0.860和0.715,均方根误差分别为0.102μg/L和0.198μg/L。反演结果表明,流溪河水库叶绿素a浓度整体较低,均在2.0μg/L以下,空间分布在湖库区较均匀,入库支流玉溪河水域叶绿素a浓度略高于湖库区。  相似文献   

12.
The paper industry is responsible for a considerable amount of greenhouse gas (GHG) emissions mainly due to its intensive energy requirements. The production of heat and power streams in a cogeneration system, i.e., a combined heat and power (CHP) plant, releases considerable amounts of GHG emissions into the atmosphere. Such emissions are already subjected to legislation globally. The amount of GHG emissions is usually calculated from the product of the total amount of energy activity multiplied by an emission factor. However, each energy output stream should get a share of emissions responsibility. This fact could assist in assigning weights to the emissions generated for power and thermal purposes in a combined heat and power plant. However, developing a suitable method of allocating emissions in a cogeneration system is still a concern and a subject research for scientists, companies and policy makers. This paper exposes and evaluates different published allocation methods and applies them to a real case of a combined heat and power plant integrated in a paper mill and proposes a new allocation method.  相似文献   

13.
于2016年8月在鸭绿江口邻近海域采集水样,讨论了鸭绿江口邻近海域夏季粒级Chl a含量的空间分布规律及环境影响因素。结果表明,调查海域总Chl a含量介于2.91~17.46 μg/L之间,平均含量为6.54±3.56 μg/L,表层Chl a含量高于底层。小型级(Micro)Chl a含量表、底层分布规律相近,高值区均位于河流入海口处;表层和底层微微型级(Pico)Chl a分布规律相近,含量值在河流入海口处由东北向西南逐渐降低。微型级(Nano)Chl a含量在表层高值区位于河流入海口处偏西方向,底层则呈现北低南高的分布趋势。Micro级Chl a为夏季鸭绿江口邻近海域总Chl a的主要贡献者,平均贡献率为55.10%;Pico级和Nano级Chl a平均贡献率为27.61%和17.29%。Chl a主成分分析结果表明:底层各粒级Chl a含量与各环境因子均呈显著正相关(p < 0.05);表层各粒级Chl a含量与盐度、透明度呈显著负相关,与硝酸盐(NO3-N)、亚硝酸盐(NO2-N)、磷酸盐(PO4-P)、DIN、氮磷比、悬浮物浓度等呈显著正相关(p < 0.05);Micro级Chl a含量与营养盐因子相关性更显著。  相似文献   

14.
本试验证明,典型的土壤真菌202号和细菌91号能氧化B(a)P。细菌氧化B(a)P的产物除顺式二氢二醇无标准品未鉴定外,其余的产物与真菌的相同。 真菌产黄青霉氧化B(a)P为反式9,10-二氢二醇-B(a)P,反式-7,8-二氢二醇-B(a)p,1,6-醌-B(a)P,6,12-醌-B(a)P,3,6-醌-B(a)P,9-OH-B(a)P,3-OH-B(a)P。 用标记~(14)CB(a)P试验,真菌产黄青霉氧化B(a)P的动力学研究指出,在96小时内能氧化B(a)P2.8%,氧化产物包含水溶性的和酯溶性的。 氧化后的B(a)P产物的最大吸收光谱与B(a)P的不同,不能用常规检定B(a)P的方法检出,但其部分产物仍具致癌作用。为了弄清B(a)P在土壤中的转化,必须进一步研究B(a)P在土壤中与其它物质的结合和钝化。  相似文献   

15.
研究表明,桑叶氟污染较重时,干茧和丝的质量受到危害,茧层重、粒茧量和公升茧粒等6项指标均显示干茧质量明显下降;在14项丝质量指标中除清洁度和强伸力外,均有明显氟危害影响.  相似文献   

16.
Before conducting a comprehensive impact assessment, such as a life cycle impact assessment (LCIA), there is a need to discuss the range of impacts which could and should be included. Up to this point of time, there has not been a comprehensive list of impacts for potential inclusion available. This research builds upon previous work which surveyed a large component of the comprehensive impact assessment field for cataloging and analysis in greater detail and then expanded it to include those midpoints, endpoints, and damages which could be covered in a more comprehensive impact assessment. In this paper, a seminal effort in the form of a meta-model is presented to facilitate an expanded discussion of the taxonomy of this field. Upon using existing models it was apparent the taxonomy needed to be structured to represent midpoint, endpoint, damage, and weighted levels as they relate to areas of protection for the impact assessment phase. Contrary to recent use in the LCIA field, a distinction will be made between an endpoint measure (which is more of a “count” of impacts) and a damage measure (which is a value-weighted aggregation of two or more endpoints). The authors present a representation of all four levels of impact assessment: midpoint, endpoint, damage, and weighted. This taxonomy was developed to include the existing impacts found in LCIA literature, and then expanded to be more comprehensive and include a larger set of impacts than are normally included within LCIA. The authors recognize this is the first of many steps necessary to capture all potential impacts that should be considered when conducting a comprehensive environmental assessment. The intent is to propose a taxonomy that would greatly facilitate the accumulation and communication of empirical and theoretical knowledge gained by offering a standard vocabulary and structure.  相似文献   

17.
上海淀山湖水环境容量评估   总被引:4,自引:0,他引:4       下载免费PDF全文
淀山湖是上海市重要的饮用水源保护区和生态涵养区.近10年来水质富营养化程度急剧增加,藻类水华频发,对上海饮用水源地水质安全构成了巨大威胁.为水污染控制和水质改善提供科学依据,利用已有评估模型评估了不同水质目标情景下淀山湖对COD、TN 和TP的最大容量,结果表明,在保持现状水质条件下,COD、TN和TP的环境容量分别为47213,8337.7,476.3t/a;水质控制目标为II类时,其环境容量分别为46325,1191.1,59.5t/a;水质目标为III类时,环境容量分别为68547,2382.2,119.1t/a.为IV类水质目标时,TN、TP的环境容量分别为3573.3,238.2t/a.  相似文献   

18.
川中丘陵区典型土地利用方式下磷素迁移的初步研究   总被引:1,自引:1,他引:0  
通过野外定位观测,对川中丘陵区坡耕地、水田与林地地表径流水中磷素迁移形态、迁移通量进行了初步研究。结果表明,坡耕地、林地磷素迁移以颗粒吸附态为主,水田磷素迁移以水溶性磷为主,所有土地利用类型径流中总磷含量已超过水体富营养化的标准。坡耕地、水田和林地地表径流水中磷迁移的通量分别为0.88 kg/(hm2.a),0.15 kg/(hm2.a)与0.33 kg/(hm2.a)。  相似文献   

19.
In mesoscale modelling of the atmosphere and in dispersion calculations often a terrain following, and therefore nonrectangular, coordinate system is used. In this paper the following questions are handled in a unified scheme: interpolation on such a nonrectangular grid, definition of the boundaries of a single cell and calculation of its volume. The interpolation is done in a boundary-following way and results in a rational interpolation formula. For comparison, two classical interpolation methods are briefly reviewed.  相似文献   

20.
Policy making is required in cases in which a public good needs to be either maintained or created, and private or civil initiatives cannot deal alone with this. Policy making thus starts with a phase of problem identification and determining whether there is a problem that needs to be dealt with. Rapidly evolving contexts exert influence on policy makers who have to take decisions much faster and more accurately than in the past, also facing greater complexity. There is a need for a method that lowers the lead time of the exploratory phase of the policy cycle. At the same time the method should create a joint understanding of the most important interactions. This paper proposes QUICKScan, a method, process and spatially explicit tool, to jointly scope policy problems in a participatory setting, investigate the most important interactions and feedbacks and assesses the state of knowledge and data of relevance to the problem. QUICKScan uses strongly moderated participatory workshops bringing together a wide range of stakeholders relevant to the policy issue. These moderated workshops jointly build an expert system in a spatially explicit tool using functionality of bayesian belief networks, python programming, simple map algebra and knowledge matrices, with a strong focus on visualization of results. QUICKScan has been applied in 70 different applications in a range of different policy contexts, stakeholders and physical locations. Through these applications participants were able to internalize the knowledge that was usually handed to them in briefs and reports, to develop a joint understanding of the main interactions and their link to impacts and to develop a problem statement and solution space in a reduced lead time. Ultimately, QUICKScan demonstrates another role of science, not solely as a knowledge production, but also facilitating the knowledge consumption.  相似文献   

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