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1.
光催化作为一种低成本且高效安全的环境净化技术,被认为是全球能源危机和环境污染问题最好的解决方式之一。赤泥作为一种固废不仅含有丰富的铁氧化物,且具有较高的比表面积、孔结构等特点,近年来,赤泥基光催化材料在光催化降解水中有机污染物的研究中备受关注。本文介绍了赤泥的特性,概括了赤泥基光催化材料的制备方法,总结了赤泥基光催化材料在光催化降解水中有机污染物方面的应用,阐述了赤泥基光催化材料催化降解水中有机污染物的机理,探讨了现有赤泥基光催化材料存在的问题。最后,基于以往的研究结果对赤泥基光催化材料未来的发展趋势提出了展望及建议。   相似文献   

2.
锐钛型二氧化钛光催化性的研究进展   总被引:1,自引:0,他引:1  
介绍了二氧化钛光催化性的国内外研究现状,综述了提高其光催化活性的改性方法,并总结了光催化氧化技术的潜在优势,指出了其发展方向。  相似文献   

3.
金属离子掺杂对TiO2光催化活性的影响综述   总被引:4,自引:2,他引:2  
光催化技术是一种新兴的高效节能现代污水处理技术.在参考近年来国内外光催化领域文献资料的基础上, 综述了金属离子修饰TiO2技术研究新进展.从离子修饰机理角度解释了离子修饰提高TiO2光催化活性的原因,进一步阐述光催化技术面临问题及发展前景.  相似文献   

4.
纳米TiO2光催化研究进展   总被引:3,自引:2,他引:1  
张文彬  周燕 《钢铁钒钛》2005,26(4):26-33
从纳米TiO2晶体结构人手,讨论了纳米TiO2光催化机理、制备技术、修饰活化及分析检测方法,重点比较了锐钛矿型和金红石型纳米TiO2的光催化性能的差异,认为锐钛矿型纳米TiO2由于具有更高的传质空位因而具有好的光催化性能;光催化活化修饰改性应以降低O对Ti的电场束缚为突破点。同时,结合实例介绍了光催化技术在不同领域的最新研究成果。  相似文献   

5.
光催化剂与建筑材料的结合是光催化领域一个重要的发展方向.文中以添加纳米TiO2的水泥为研究对象,以甲基橙的光催化降解活性为指标,考察了光催化水泥用量、水泥中TiO2的含量、水泥水化龄期以及甲基橙初始浓度对甲基橙降解效果的影响.结果表明,在紫外光照射下,当甲基橙的初始浓度为5 mg/L,光催化水泥用量为3 g/L,水泥中TiO2含量为5%时,光催化效率最高;延长水泥水化龄期,光催化水泥对甲基橙的吸附性能和降解性能均有所下降;提高甲基橙初始浓度,可以增强光催化水泥对甲基橙的吸附性能,当初始浓度达到15 mg/L时,光催化水泥的吸附量可达54.5%.  相似文献   

6.
影响纳米材料TiO2光催化活性的因素   总被引:10,自引:4,他引:10  
崔玉民 《稀有金属》2006,30(1):107-113
讨论了TiO2光催化技术研究现状、探讨了光催化反应机制, 分析了提高光催化反应活性的途径, 并讨论了影响纳米TiO2光催化活性的主要因素 一般而言, 锐钛矿型TiO2的光催化活性高于金红石型TiO2;晶粒尺寸小, 光生电子和空穴从TiO2体内扩散到表面的时间短, 它们在TiO2体内的复合几率减小, 光催化活性高;贵金属沉积可提高催化剂表面光生载流子的分离效率, 有利于生成更多的·OH;半导体耦合可提高系统的电荷分离效果, 扩展对光谱吸收范围;金属离子掺入TiO2晶格中可能引起晶格位置缺陷或改变结晶度, 抑制电子与空穴的复合, 延长载流子的寿命, 从而使光催化性能得以改善;TiO2表面羟基的数量直接影响光催化效率.  相似文献   

7.
半导体多相光催化研究进展及应用技术   总被引:6,自引:0,他引:6  
半导体光催化氧化技术是一种新型的现代化水处理技术 ,对多种有机物有明显的降解效果 ,具有广泛的前景 ,近年来 ,半导体光催化氧化已成为光化学领域和环保领域中的研究热点之一 .本文介绍了半导体多相光催化原理、光催化剂的制备和在环境保护、卫生保健等方面的应用 ,提出了光催化技术存在的问题及发展方向  相似文献   

8.
影响TiO2光催化活性的因素及提高其活性的措施   总被引:6,自引:0,他引:6  
文章详细分析了影响TiO2光催化活性的一些因素,如TiO2自身的性质、纳米TiO2的表面修饰、光催化反应系统的工艺条件、光催化反应器、辅助能量场的引入等等。讨论了提高TiO2光催化活性的措施。指出了存在的问题和研究方向。  相似文献   

9.
采用溶胶-凝胶法制备了具有光催化性能的TiO2纳米粉体,通过差热-热重、红外光谱分析了碳黑对其光催化性能的影响。结果表明:碳黑的加入可使TiO2纳米粉改性,提高其比表面积,TiO2纳米粉光催化活性显著提高,当碳黑加入量摩尔分数为0.75%时,制得的TiO2纳米粉的光催化活性最高。  相似文献   

10.
卤族元素掺杂改性TiO_2光催化剂研究进展   总被引:1,自引:0,他引:1  
廉价、环境友好、高稳定性并具有可见光光催化活性的光催化剂将是光催化发展进一步走向实用化的关键。卤素掺杂TiO2是具有可见光光催化活性的光催化剂,经卤素掺杂可以使TiO2的禁带宽度减小,从而使TiO2的吸收边红移。对TiO2的氟、氯、溴、碘掺杂的国内外研究现状进行了系统评述,分析了提高TiO2可见光活性的原因,指出经卤族元素掺杂,TiO2在保持紫外区光催化活性的前提下,大大增加了其可见光响应能力,且有益于具有光催化活性晶相TiO2的形成。  相似文献   

11.
无缝钢管中非金属夹杂物特性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
峰位于4869 eV位置,对应于元素锡的四价氧化态。锡泥中含有的主要成分为SnO2。  相似文献   

12.
Due to fast development of Chinese steel industry,continuous adjustment of product,improvement of quality,research of value-added product,RH technology is significantly developed.More and more steel plants are covered with RH facilities.RH ratio is growing rapidly as well.Over past decade,through assimilating advanced foreign technologies and further refining them,Chinese large scale steel plants master the technology of RH production,operation,maintenance and make it more widespread.RH functions are well applied and improved.RH is more widely effectively put into use.Through independent innovation,RH core devices and technology,such as RH vacuum pump,oxygen top lance,vacuum vessel preheating lance,ladle lifting device etc.have realized localization.The development of equipment design,software design,equipment manufacturing technology,equipment mounting,test technology and EPC management makes equipment configuration more flexible,equipment more functional and stable,easier to operate and maintain.It also guarantees highly effective and low energy consumption production and quality of steel,reaches international advanced level,lowers the cost of RH construction and operation,makes after-sake service more convenient. How to continuously optimize and develop RH process,equipment and control technology,in order to meet the needs of product with more reasonable and economic process,exploit potentialities,build more effective,lower cost,lower energy consumption,protecting environment RH facilities will be the key point of future RH technology development in China.  相似文献   

13.
This paper highlights technology development for space exploration. It draws on the proceedings of Space 88, Engineering, Construction, and Operations in Space, which includes 125 papers and 1,349 pages providing in‐depth discussions of space policy, extraterrestrial basing, space stations, orbiting structures, and areas of special interest. In the space station and orbiting structures (orbital facilities) section, papers discuss the engineering, construction, and operations of orbiting space systems. Papers in the extraterrestrial basing section deal with the engineering, construction, and operations challenges faced in development of bases and operations on extraterrestrial bodies. The special interest (interacting disciplines) section provides a discussion of challenges facing us in meeting needs for space power, life support, human factors, astronomy, education, and management. The purpose of this volume on engineering, construction, and operations of facilities and bases in space is to encourage and stimulate the development of the required technologies. The concluding section of this paper focuses on space policy and a view toward the future.  相似文献   

14.
Both hardiness and religiousness share spirituality, in the sense of searching for meaning in one's life, and have been shown to have a buffering effect on stresses that maintains and enhances performance, morale, and health. This study investigates how hardiness and religiousness compare in their relationship to depression, anger, and the coping and social support mechanisms whereby they may have these relationships. Participants were military and governmental personnel who completed accepted measures of hardiness, religiousness, and other variables on a volunteer basis. Correlational and multiple regression analyses showed that, by comparison with religiousness, hardiness has the larger and more comprehensive negative relationship with depression and anger, and positive relationship with coping and social support. The conceptual and empirical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
中国高炉炼铁技术装备发展成就与展望   总被引:1,自引:1,他引:0  
张福明 《钢铁》2019,54(11):1-8
 近40年来,我国钢铁工业取得了巨大进步,钢铁产量连续多年居世界第一。我国高炉炼铁技术装备在大型化、现代化、高效化、长寿化等方面发展成就显著。2000年以来,一批5000m3以上特大型高炉、500m2以上大型烧结机、7.63m超大容积焦炉和年产400万t/a以上大型球团生产线相继建成投产,一系列自主研发、集成创新的炼铁关键技术在生产实践中取得重大应用成效。在技术装备大型化的同时,高炉富氧喷煤、无料钟炉顶、煤气干法除尘、顶燃式热风炉及高风温、高效低耗烧结技术、大型清洁炼焦技术等先进技术及其装备研发与应用成效显著,有力推动了炼铁技术装备进步。到本世纪中叶,我国钢铁工业格局和流程结构将发生重大变革,减量化、绿色化、智能化、高效化将是未来一个时期炼铁技术装备的主要发展趋势。  相似文献   

16.
Compared to storm water runoff, urban roadway snow exposed to traffic and winter maintenance practices has a much greater capacity to accumulate and retrain heavy metals and other anthropogenic constituents. Heavy metals once released in the environment are not degraded and partition between the dissolved and particulate-bound fractions. Residence time, solid loadings, alkalinity, hardness, and pH influence partitioning. Accretion and partitioning of Pb, Cu, Cd, Zn, Al, Ca, Na, Mg, and Fe from a series of urban highway sites in Cincinnati, Ohio, are compared to temporal accretion trends at a control site removed from the highway environment. Results from partitioning analysis indicate that Pb, Cu, Cd, Zn, Al, Mg, and Fe were all highly particulate bound, while Na and Ca were mainly dissolved for all highway sites. Partition coefficients for most heavy metals in snowmelt ranged from 103 to 106?L/kg. Concentrations for Pb, Cu, Cd, Zn, and cyanide were orders of magnitude higher than at the control site and exceeded storm water runoff concentrations by one to two orders of magnitude. For residuals analyses, the specific surface area generally increased with decreasing particle size while the predominance of total surface area (SA) was associated with the medium to coarser size fractions. Heavy metal mass trends followed similar general trends to that of the SA. Characterization of accretion and partitioning of these metals is a necessary first step toward development of management and treatment strategies designed to address urban snow pollution.  相似文献   

17.
以再生铜电解过程中产生的高砷高锡铅阳极泥为原料,采用火法—湿法联合工艺,经水洗—脱砷—酸浸—蒸发结晶,在有效回收锡、铅、铜等有价金属的同时脱除砷。结果显示,砷的脱除率达到96.49%,锡、铅、铜、镍、锑的回收率分别为96.80%、99.32%、93.72%、94.15%、97.80%。  相似文献   

18.
ICP-AES法测定稀土金属中的钛、钼、钨、铌和钽   总被引:2,自引:0,他引:2  
崔爱端  杜梅  刘晓杰 《稀土》2005,26(1):57-59
针对试样特点拟定了加大称样量以减轻偏析,以浓硝酸溶解样品破坏碳化物,加入氢氟酸助溶,分离稀土基体同时络合钛、钼、钨、铌和钽的方法,无须基底匹配,采用工作曲线法成功地测定了金属镧、铈、镨、钕、钐、铕、钆、铽、镝、钇中的钛、钼、钨、铌和钽量,测定范围:0.0050%~0.50%。  相似文献   

19.
A review of ceramic matrix composites is presented as related to their type, use, and fabrication. Ceramic composites have the potential for high fracture toughness, resistance to catastrophic failure, high strength, low density, low thermal expansion, and high temperature capability and oxidation resistance. For continued development, there are a number of key technical needs including new refractory matrices, new stable fibers, and inert coatings for flbers, as well as affordable techniques which produce the desired composite properties and accomplish complex shape capability. A better materials understanding is necessary, including fiber∕matrix interaction, and mechanics∕structure∕property relationships. Finally, technologies for transition to practice are required, including advanced materials characterization, component design methodology, large scale fabrication, attachment techniques, and nondestructive evaluation. While these composites are in the research and development stage, they offer the structural engineer excellent rigidity, high strength‐to‐weight ratio, high temperature capability and a noncatastrophic failure mode. Potential applications include turbine and internal combustion engines, aerospace structures, and high temperature leading edges and skins. A current application is the use of SiC whisker reinforced Al2O3 matrix composites as cutting tools. Significantly increased cutting speeds, improved interrupted cut performance and increased tool life are found.  相似文献   

20.
This article explores the concept of self-relatedness, integrating ideas drawn from attachment theory, developmental studies, object relations, and interpersonal neurobiology with a multiplicity model of self. I suggest that because self-regulation begins as a dyadic interpersonal process between child and attachment figure, the mind renders such regulatory abilities across the life span via an analogous, intra-relational dyad. This “internal attachment system,” comprising states representing our subjective experience and states reflecting on and appraising that experience coordinates its activity in ways that best regulate the individual's affects, thoughts, perceptions, and behavior. Chronic trauma and neglect create patterns of intrapsychic relatedness that compromise connection, receptivity, adaptive engagement, and harmony among elements of the self system, thereby disrupting the mind's development toward greater coherence and complexity (Siegel, 2007). This article will also discuss the clinical application of intra-relational principles with pervasively maltreated people using a method called Intra-relational (I-R) Accelerated Experiential Dynamic Psychotherapy (Lamagna & Gleiser, 2007). Applying Accelerated Experiential Dynamic Psychotherapy's use of dyadic affect regulation, the tracking of emergent somatic experience, and the processing positive effects associated with transformation to inner work with various internal parts of the self, I-R seeks to foster attunement and receptivity among previously dissociated parts of the individual. Creating intrapsychic safety provides an opening through which defensively excluded memories and associated emotions, thoughts, and impulses can be processed and integrated and increasingly coherent and complex forms of self-organization can be achieved. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

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