活性炭吸附和脱附-等离子体氧化净化有机废气的研究

根据滑动弧放电等离子体适于降解高浓度有机物废气的特性,结合活性炭吸附法,提出了吸附器的吸附浓缩和热脱附-等离子体氧化净化有机废气的方法。在活性炭吸附过程中,最初2 h内甲苯净化率达到100%,随着时间的增加净化率下降;在热脱附滑动弧放电等离子体净化过程中,甲苯降解效率最高为97.3%。将滑动弧放电等离子体反应器出口气相产物收集进行FT-IR检测,发现放电后有CO2、CO、H2O和NO2产生,并分析了甲苯的降解机理。     

模拟黑水的生物处理

针对以糖蜜配制的半人工黑水生物处理时除磷效率下降和污泥膨胀的现象,利用序批式反应器(SBR)进行了实验分析,比较了以蔗糖和糖蜜为主要碳源时除磷效果的差异,并探讨了污泥膨胀发生的原因。研究表明,以糖蜜为主要碳源配制模拟黑水时的除磷效果比蔗糖为碳源时差,主要是由于GAOs的竞争性代谢所致。以糖蜜为碳源的条件下,污泥的胞外聚合物含量是正常活性污泥的一倍以上,导致污泥沉降性能变差;糖蜜碳源时的夏季高温条件下丝状菌大量生长也是导致污泥膨胀的重要原因。     

采油废水回注处理技术的现状及展望

阐述了目前采油废水回注处理的技术及工艺现状,重点探讨了膜分离技术在采油废水回注处理中的研究及应用情况,分析了各技术存在的问题,并展望了采油废水回注处理技术的发展趋势。     

Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction

Fractionation of plutonium isotopes (²³⁸Pu, ^239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially designed extraction column. Plutonium in the fractions from the sequential extraction was separated by ion exchange chromatography and measured using alpha spectrometry. The analytical results show a higher mobility of plutonium in bio-shielding concrete, which means attention should be paid to the treatment and disposal of nuclear waste from decommissioning.     

Inorganic iodine incorporation into soil organic matter: evidence from iodine K-edge X-ray absorption near-edge structure

The transformation of inorganic iodine (I⁻ and IO₃⁻) incubated in soils with varying amounts of organic matter (Andosols from the surface layer of an upland field and forest, as well as Acrisols from surface and subsurface layers of an upland field) was investigated by using the iodine K-edge X-ray absorption near-edge structure (XANES). After 60 d of reaction, both I⁻ and IO₃⁻ were transformed into organoiodine in surface soils containing sufficient amounts of organic matter, whereas IO₃⁻ remained unchanged in the subsurface soil of Acrisols with low organic matter contents. Transformation of IO₃⁻ into organoiodine was not retarded when the microbial activity in soil was reduced by γ-ray irradiation, suggesting that microbial activity was not essential for the transformation of inorganic iodine into organoiodine. Soil organic matter has the ability to transform inorganic iodine into organoiodine.     

中国能源可持续发展区域差异及其因素分析

该文在明晰中国能源可持续发展内涵的基础上,从能源足量、可持续、合理供给;能源与水、土地、森林等资源配套能力;国家可持续能源政策与地区规划的融合,减缓环境资源的损耗;环境可持续性四个目标出发,构建了区域能源可持续发展指标体系。从定量的角度刻画中国能源可持续发展的区域差异,解析影响中国能源可持续发展的主要因素。研究结果表明,可持续能源政策与环境的可持续性是制约能源可持续发展的关键环节;能源与森林、土地资源的配套能力是重要基础;能源供应能力是核心所在;从中国东、中、西部来看,西部地区是中国能源可持续性最强的地区,中部次之,东部能源可持续性最弱;从中国八大区域来看,能源可持续性沿海地区最弱,东北和长江中游地区次之,大西北、西南和黄河中游地区最强。本文作者最后认为多元化发展,提升能源供应能力;建立健全环境税收制度,增强环境可持续性;因地制宜,是促进中国区域能源可持续发展的必然选择。     

湖北“两圈”区域发展可持续性评价与预测

利用可持续发展指数（SDI）对湖北“两圈”各市州发展现状进行了评价,而后利用9年的人均生物资源生态承载量年平均增长率、人口年平均增长率和足迹承载量比值年平均增长率及2006年相关数据对未来44年进行了预测。结果表明,截至2006年底,湖北省有一半以上国土面积的生物资源开采超过当地土地负荷,人均生物资源生态承载量持续下降,资源日益紧张,呈不可持续发展;武汉城市圈2006年生物资源生态足迹超出生物资源生态承载量的32%;鄂西生态文化旅游圈（简称：鄂西生态圈）除襄樊、荆州、荆门因人口多,生物资源生态足迹较大等原因导致SDI值较高外,其他市州的SDI值均较低;神农架的SDI最小;武汉城市圈人均生物资源生态承载量呈负增长,人口控制较好,足迹承载量比值增长较快;鄂西生态圈人均生物资源生态承载量呈负增长,增长速率大于武汉城市圈和湖北省,人口控制较差,足迹承载量比值增长较慢;按照现有发展模式,无论是武汉城市圈还是鄂西生态圈,无论其当前发展是可持续性还是不可持续的,未来他们都将进入不可持续的发展状态。因此,对“两圈”进行规划时要根据各自发展现状制定长期、科学的发展规划.     

Evaluation of C18 solid‐phase extraction cartridges for the isolation of select pesticides and metabolites

Abstract

Nine different C₁₈ solid‐phase extraction (SPE) cartridges were evaluated for their efficiency at extracting nine pesticides and two s‐triazine metabolites from spiked deionized water samples. The SPE cartridges were found to contain nitrogen (N) and/or phosphorus (P) contaminants and varied in their extraction efficiency for certain pesticides and metabolites. Four of the nine SPE cartridges gave acceptable (70 to 120%) pesticide and metabolite recovery percentages, while five cartridges had marginal (50 to 70%) to poor (< 50%) recoveries. Statistical analyses showed that the poor to marginal recoveries found for three compounds could not be explained by considering several indigenous chemical and physical traits of the cartridge. It is suggested that proper SPE cartridge selection for pesticide recovery should be evaluated using several different cartridges.     

Metabolism of the Nonylphenol Isomer [Ring-U-14c]-4-(3′,5′-Dimethyl-3′-Heptyl)-Phenol by Cell Suspension Cultures of Agrostemma githago and Soybean

Abstract

The biotransformation of the nonylphenol isomer [ring-U-¹⁴C]-4-(3′,5′-dimethyl-3′-heptyl)-phenol (4-353-NP, consisting of two diastereomers) was studied in soybean and Agrostemma githago cell suspension cultures. With the A. githago cells, a batch two-liquid-phase system (medium/n-hexadecane 200:1, v/v) was used, in order to produce higher concentrations and amounts of 4-353-NP metabolites for their identification; 4-353-NP was applied via the n-hexadecane phase. Initial concentrations of [¹⁴C]-4-353-NP were 1 mg L^?1 (soybean), and 5 and 10 mg L^?1 (A. githago). After 2 (soybean) and 7 days (A. githago) of incubation, the applied 4-353-NP was transformed almost completely by both plant species to four types of products: glycosides of parent 4-353-NP, glycosides of primary 4-353-NP metabolites, nonextractable residues and unknown, possibly polymeric materials detected in the media. The latter two products emerged especially in soybean cultures. Portions of primary metabolites amounted to 19–22% (soybean) and 21–42% of applied ¹⁴C (A. githago). After liberation from their glycosides, the primary 4-353-NP metabolites formed by A. githago were isolated by HPLC and examined by GC-EIMS as trimethylsilyl derivatives. In the chromatograms, eight peaks were detected which due to their mass spectra, could be traced back to 4-353-NP. Seven of the compounds were side-chain monohydroxylated 4-353-NP metabolites, while the remaining was a (side-chain) carboxylic acid derivative. Unequivocal identification of the sites of hydroxylation/oxidation of all transformation products was not possible. The main primary metabolites produced by A. githago were supposed to be four diastereomers of 6′-hydroxy-4-353-NP (about 80% of all products identified). It was concluded that plants contribute to the environmental degradation of the xenoestrogen nonylphenol; the toxicological properties of side-chain hydroxylated nonylphenols remain to be examined.     

Electrochemical Monitoring of Methylparathion Degradation in an Acid Aqueous Medium in Presence of Cu(II)

Abstract

A study was undertaken to determine the effect of Cu(II) in degradation of methylparathion (o,o-dimethyl o, 4-nitrophenyl phosphoriotioate) in acid medium. Initial electrochemical characterization of Cu(II) and methylparathion was done in an aqueous medium at a pH range of 2–7. Cu(II) was studied in the presence of different anions and it was observed that its electroactivity depends on pH and is independent of the anion used. Methylparathion had two reduction signals at pH ≤ 6 and only one at pH > 6. The pesticide's transformation kinetic was then studied in the presence of Cu(II) in acid buffered aqueous medium at pH values of 2, 4, and 7. Paranitrophenol appeared as the only electroactive product at all three pH values. The reaction was first order and had k values of 5.2 × 10^?3 s^?1 at pH 2, 5.5 × 10^?3 s^?1 at pH 4 and 9.0 × 10^?3 s^?1 at pH 7. It is concluded that the principal degradation pathway of methylparathion in acid medium is a Cu(II) catalyzed hydrolysis reaction.