载银纳米TiO_2光催化降解水中有机污物

以TiOSO4和TiOCl2 为原料 ,合成出锐钛相和金红石相的相对含量分别约为 85 %和 1 5 %的纳米TiO2 光降解催化剂。在纳米TiO2 表面担载质量分数为 0 5 %的银后 ,不但能较好地提高催化活性和使用寿命 ,而且表现出特有的絮凝作用 ,使催化剂易于分离 ,达到多次循环使用的目的。对光催化降解活性黑模拟污水 ,以及蒽醌类染料、糖厂等实际污水发现 ,这种纳米TiO2 具有活性高、寿命较长的特点 ,且能多次循环使用 ,降低了处理污水的成本。

过氧化氢湿法氧化模拟有机污物的研究

用过氧化氢湿法氧化处理有机污物,研究了过氧化氢的投加量和投加方式,催化剂以及pH值等对反应的影响.结果表明,为提高H2O2的利用率,H2O2应以间歇式投加,选取Fe2+作催化剂,体系pH值为1～2.为保证反应快速启动和平稳进行,反应时将催化剂总投加量的1/3提前与要分解氧化的物质混合一段时间,剩余2/3在反应进行中连续定量滴加,并于反应结束前半小时投加完毕.正交试验表明,分解2.00 g界面污物的最佳实验条件为:pH＝1,10 mL 30%H2O2溶液,10 mL 0.1 mol/L Fe2+溶液.反应结束时,反应釜底部的白色残余物经红外分析和元素分析表明主要是磷酸盐.H2O2湿法氧化能够有效分解TBP/OK,HDBP/OK溶液和界面物.

泥塑文物表面有机污物的激光去除与损伤研究

为了实现泥塑文物表面鸟粪类有机污物的激光无损去除,搭建高速摄像光学滤光放大采集系统,进行不同激光能量密度下的泥塑文物表面有机污物层去除实验,采集激光作用到泥塑文物表面有机污物层的动态去除过程,并研究不同去除模式的能量阈值及对基材的损伤行为。结果表明:在不同的激光能量密度作用下,泥塑文物表面有机污物层会出现烧蚀效应和振动效应,烧蚀效应去除过程中出现燃烧现象并伴随大量白烟的产生,振动效应去除过程中会出现有机污物层开裂和颗粒状飞溅现象,有机污物层去除后基体主要损伤形式有灼烧损伤和凹坑损伤。

西部和南部太平洋表层海水中的重金属及有机沾污物

根据1992年冬季在太平洋西部和南部10个站位采集的表层海水样品分析,探讨了太平洋表层海水中重金属及有机沾污物的浓度水平和分布特征.结果表明,表层水中大部分重金属及∑666、油类等均可检出,有的浓度水平较高;沾污物在不同的水团中浓度分布有差异,既是水团特征的表现,也是区域性沾污水平的反映;大气中沾污物质的长距离传输也是调查区表层水中的沾污物的一个重要来源.

表面残留有机沾污物的TOF－SIMS及XPS研究

飞行时间次级离子质谱（ＴＯＦ－ＳＩＭＳ）结合Ｘ射线光电子能谱（ＸＰＳ）分析了用化学方法清洗后、银片上残留的未知的有机物。结果显示，有机沾污物主要是一些含１８～３０碳原子、碳链饱和度很高的酮类和酯类化合物；个别有机物可能是硬脂酰胺。这种结构特点使有机物中的Ｃ＝Ｏ基团易于采取氧原子指向基体表面的取向，通过带部分负电荷的氧原子与金属基体镜像力的作用而增强粘附。ＴＯＦ－ＳＩＭＳ二维离子像显示有机沾污物在银片表面上呈极稀薄的均匀分布。

柑桔园有机肥施用技术

有机肥种类很多．包括畜禽粪尿、炭土、有机污物、作物秸秆，还有绿肥、饼粕、草木灰、污泥、生活垃圾与污水等等，其中畜禽粪尿除少量用于燃料与工业原料外．大部分可用于有机肥。长期以来，广大果农都只注意到它的优点而忽略了其弊端．如果长期大量使用未经无害化处理的畜禽粪肥．对土壤环境和农产品质量都会造成威胁．还可能对人体健康或其它生物产生潜在威胁。因此．果园使用有机肥必须经过腐熟发酵．

氯代有机污染物辐照脱氯的研究进展

本工作对电离辐射引发的典型氯代有机污染物的脱氯降解机理进行了综述,重点回顾了氯酚、多氯联苯、三氯乙烯和四氯乙烯辐照脱氯降解的研究现状。氯酚在氧化条件下与羟基自由基(·OH)反应首先形成·OH加成物,然后逐步脱氯;在还原条件下水合电子(e_(aq)^-)与氯酚直接发生选择性反应脱氯,生成苯酚和氯离子。多氯联苯在有机溶剂中的辐照降解反应主要通过链式反应逐渐脱去其中的氯原子,反应的最终产物是氯离子和联苯。三氯乙烯(TCE)和四氯乙烯(PCE)在氧化条件下与羟基自由基(·OH)反应,主要产物有CO_2、HCOOH和HCl等。与氧化途径相比,氯代有机物的辐照还原脱氯具有降解效率高、产物单纯、剂量小等优势。

活性炭对水中微量有机污染物去除的初步探讨

从活性炭物理结构和表面化学官能团的描述入手,对活性炭的吸附机理作初步探讨。介绍了活性炭比表面积的测定;活性炭吸附能力的评价活性炭对挥发性酚、苯胺、三氯甲烷、四氯化碳的吸附实验方案;阐述了不同质量的活性炭对水中微量有机污染物去除能力的不同。

Preparation of three-dimensional interconnected mesoporous anatase TiO_2-SiO_2 nanocomposites with high photocatalytic activities

In this article, we report the preparation of a three-dimensional（3D） interconnected mesoporous anatase TiO2-SiO2 nanocomposite. The nanocomposite was obtained by using an ordered two-dimensional（2D） hexagonal mesoporous anatase 70 TiO2-30 SiO2-950 nanocomposite（crystallized at 950 °C for 2 h） as a precursor, NaO H as an etchant of SiO2 via a ＂creating mesopores in the pore walls＂ approach. Our strategy adopts mild conditions of creating pores such as diluted NaO H solution, appropriate temperature and solid/liquid ratio, etc. aiming at ensuring the integrities of mesopores architecture and anatase nanocrystals. XRD, TEM and N2 sorption techniques have been used to systematically investigate the physico-chemical properties of the nanocomposites. The results show that the intrawall mesopores are highly dense and uniform（average pore size 3.6 nm）, and highly link the initial mesochannels in a 3D manner while retaining mesostructural integrity. There is no significant change to either crystallinity or size of the anatase nanocrystals before and after creating the intrawall mesopores. The photocatalytic degradation rates of rhodamine B（RhB, 0.303 min^–1） and methylene blue（MB, 0.757 min^–1） dyes on the resultant nanocomposite are very high, which are 5.1 and 5.3 times that of the precursor; even up to 16.5 and 24.1 times that of Degussa P25 photocatalyst, respectively. These results clearly demonstrate that the 3D interconnected mesopores structure plays an overwhelming role to the increments of activities. The 3D mesoporous anatase TiO2-SiO2 nanocomposite exhibits unexpected-high degradation activities to RhB and MB in the mesoporous metal oxide-based materials reported so far. Additionally, the nanocomposite is considerably stable and reusable. We believe that this method would pave the way for the preparation of other 3D highly interconnected mesoporous metal oxide-based materials with ultra-high performance.

Adsorptive and catalytic properties in the removal of volatile organic compounds over zeolite-based materials

Volatile organic compounds（VOCs） are a major component in air pollutants and pose great risks to both human health and environmental protection. Currently, VOC abatement in industrial applications is through the use of activated carbons as adsorbents and oxide-supported metals as catalysts. Notably, activated carbons easily adsorb water, which strongly hinders the adsorption of VOCs; conventional oxides typically possess relatively low surface areas and random pores, which effectively influence the catalytic conversion of VOCs. Zeolites, in contrast with activated carbons and oxides, can be designed to have very uniform and controllable micropores, in addition to tailored wettability properties, which can favor the selective adsorption of VOCs. In particular, zeolites with selective adsorptive properties when combined with catalytically active metals result in zeolite-supported metals exhibiting significantly improved performance in the catalytic combustion of VOCs compared with conventional oxide-supported catalysts. In this review, recent developments on VOC abatement by adsorptive and catalytic techniques over zeolite-based materials have been briefly summarized.

光催化技术在环境治理方面的应用研究

光催化技术在治理环境方面具有潜在的应用价值,是当今环保领域的研究热点。因此,研究光催化反应机理对解决当今的能源危机与环境污染具有重要的意义。本文研究了纳米半导体材料的光催化原理及对有机污物的降解和光致杀菌的应用。

猪场消毒前为什么要进行清洁

任何消毒剂如果想在养猪场中发挥完全的消毒灭菌效力，必须事先对消毒的场地及猪舍进行彻底地清洁。从构建有效的猪场生物安全程序的角度看，猪舍内的粪便、黏液等有机污物被清扫干净后，也要求彻底清洗猪舍，然后才能开始消毒工作。目前猪场采用的清洗方式主要是高压水流冲洗，这种清洗方式虽然工作量很大，但难以达到最佳的清洗效果，同时由于操作人员常常忽略一些难以清洗的区域如墙角、椽梁、管线和风扇等处，因此清洁工作又是猪场做得最不彻底的一项工作。

Impacts of Agricultural Non-point Pollution on Water-source Area in Songhua Dam

[Objective] The aim was to research impacts of agricultural non-point pol- lution on water-source region in Songhua Dam, laying foundation for control of water pollution and scientific protection of water-source region. [Method] Water in Muyang River, lengshui River and Zizania aquatica region were sampled to measure content of pollutants in water and conclude relation between water contamination and agri- cultural non-point pollution to find the major cause of pollution. [Result] Organic pollu- tant in Muyang River was higher; N and P contents in Lengshui River were higher; the measured indices in Zizania aquatica region excessively exceeded related stan- dard. [Conclusion] The chemical fertilizers and pesticides are the toxic materials lead- ing to water contamination and constitute a major cause of pollution in Songhua Dam water-source region. Agricultural non-point pollution should be controlled in a scientific way.

新产品与新技术(13)

厚度0．08mm的世界最薄基板;0.7μm宽线与0．25μm直径点之喷墨印刷技术;阻焊剂自动精密喷涂装置;电镀液中有机污物快速吸除;适宜半加成法制作20μm节距线路用的光致抗蚀干膜.

微生物电池

美国斯坦福大学的技术人员正在研究一种微生物电池，这种电池通过使微生物消化有机污物进而产生电能。目前，这一微生物电池的样品已经问世，与普通D型电池的大小相似，且同样具有正负极。

日本研发出一种有良好自洁功能的新型纤维

日本Exlan工业通过在丙烯酸纤维中掺入光触媒氧化钛，开发出一种具有良好自洁功能的新型纤维“SelfClear”，并计划于2006年春开始上市。这种纤维具有以下功能：（1）包括四大恶臭（氨、硫化氢、三甲胺以及硫醇）和烟臭在内，可消除苯、甲苯、二甲苯等挥发性有机化合物的“除臭功能”；（2）以黄色葡萄球茵为代表的“抗茵除臭功能”；（3）清除烟碱等有机污物的“防污功能”。

Sorption of Heavy Metal and Organic Pollutants on Modified Soils

Sorption characteristics of both an organic pollutant (phenol) and a heavy metal (cadmium ion) on the clay layer of a Lou soil (Eum-orthic Anthrosol in Chinese Soil Taxonomy) along with the sorption mechanism were investigated using three soil treatments: modification with a cationic surfactant cetyltrimethylammonium bromide added at an amount equivalent to 50% and 100% of the soil CEC (50%CB and 100%CB), modification with an amphoteric surface-modifying agent dodecyldimethylbetaine (commercially known as BS-12) added at an amount equivalent to 50% and 100% of the soil CEC (50% BS and 100%BS), and an unmodified control (CK). Results showed that the BS soil treatments increased sorption of both the heavy metal Cd2+ and the organic pollutant phenol. The equilibrium sorption amount of Cd2+ decreased in the order: 50%BS > 100%BS > CK > 50%CB > 100%CB, with the BS soil treatments being about 1.3 to 1.8 times higher and the CB soil treatments about 23% to 41% lower than CK. Both the single-site and two-site Langmuir models could be applied to describe the sorption of Cd2+ in each soil treatment. The equilibrium sorption amount of phenol on the soil samples decreased in the order: 100%CB > 50%CB > 100%BS > 50%BS > CK, with the CB soil treatments being 41.0 to 79.6 times higher and the BS soil treatments 4.0 to 8.3 times higher than CK. The Freundlich equation could also be used to describe the sorption characteristics of phenol. In the BS soil treatments, both an organophobic long carbon chain and hydrophilic charged groups resulted in a relatively strong sorption ability for both heavy metals and organic pollutants. In addition, the sorption ratio K, the ratio of phenol sorption amount of the modified soil to that of CK, increased initially and decreased later with the amount of phenol added, and the critical sorption ratio KC, the peak value of the sorption ratio curve plotted against the added phenol concentration, was a good index for evaluating the sorption ability of phenol in the soil.

Novel SiO2 nanoparticle-decorated BiOCl nanosheets exhibiting high photocatalytic performances for the removal of organic pollutants

Novel SiO2/BiOCl composites were fabricated by decorating BiOCl nanosheets with SiO2 nanoparticles via a simple hydrothermal process. The as-prepared pure BiOCl and SiO2/BiOCl composites were intensively characterized by various techniques such as XRD, FT-IR, SEM/TEM, BET, UV-vis, DRS, XPS, and photocurrent measurements. The SiO2/BiOCl composite nanosheets displayed high photocatalytic activity and excellent stability in the degradation of organic pollutants such as phenol, bisphenol A (BPA), and rhodamine B (RhB). With respect to those over bare BiOCl, the degradation rates of RhB, BPA, and phenol over 1.88% SiO2/BiOCl increased 16.5%, 29.0%, and 38.7%, respectively. Radical capturing results suggested that h^+ is the major reactive species and that hydroxyl (·OH) and superoxide (·O2^-) radicals could also be involved in the degradation of organic pollutants. The enhanced photocatalytic performances of SiO2/BiOCl composites can be mainly attributed to the improved texture and the formation of intimate SiO2/BiOCl interfaces, which largely promoted the adsorption of organic pollutants, enhanced the light harvesting, and accelerated the separation of e^– and h^+.

Nanofiber-based enrichment device for sampling organic contaminants in vacuum environment

A novel method for sampling and enriching organic volatile contaminants in the vacuum environment combined with qualitative analysis based on the vacuum simulation test is proposed. A nanofiber is used as absorbent to collect the organic volatile contaminants in the vacuum environment and then eluted by methanol. The eluent is analyzed by gas chromatography （ GC ） and gas chromatography-mass spectrometry （GC/MS） to identify the composition of the organic contaminants. The nanofiber is composed of polystyrene and it is prepared by electrospinning. Before being used, the nanofiber is processed by ultrasound in ethanol for 15 min to remove some impurities and dried in an oven at 60 ℃, and then 10 mg of the nanofiber is wrapped in a thermoplastic polyester fabric pocket. The vacuum pump oil and di-iso-decyl phthalate （DIDP） are chosen as absorbates to test the absorbent performance of the nanofiber in the vacuum environment. Experiments are performed under the pressure of 10-4 and 103 Pa, respectively. It is shown that the nanofiber-based enrichment device can be used to adsorb the organic contaminants in the vacuum simulation environment.