二恶英的性质、危害及处理方法

介绍了二恶英的性质、来源、危害、去除及降解方法。     

Nitrogen dynamics following grain legumes and subsequent catch crops and the effects on succeeding cereal crops

The effects of faba bean, lupin, pea and oat crops, with and without an undersown grass-clover mixture as a nitrogen (N) catch crop, on subsequent spring wheat followed by winter triticale crops were determined by aboveground dry matter (DM) harvests, nitrate (NO₃) leaching measurements and soil N balances. A 2½-year lysimeter experiment was carried out on a temperate sandy loam soil. Crops were not fertilized in the experimental period and the natural ¹⁵N abundance technique was used to determine grain legume N₂ fixation. Faba bean total aboveground DM production was significantly higher (1,300 g m^?2) compared to lupin (950 g m^?2), pea (850 g m^?2) and oat (1,100 g m^?2) independent of the catch crop strategy. Faba bean derived more than 90% of its N from N₂ fixation, which was unusually high as compared to lupin (70–75%) and pea (50–60%). No effect of preceding crop was observed on the subsequent spring wheat or winter triticale DM production. Nitrate leaching following grain legumes was significantly reduced with catch crops compared to without catch crops during autumn and winter before sowing subsequent spring wheat. Soil N balances were calculated from monitored N leaching from the lysimeters, and measured N-accumulation from the leguminous species, as N-fixation minus N removed in grains including total N accumulation belowground according to Mayer et al. (2003a). Negative soil N balances for pea, lupin and oat indicated soil N depletion, but a positive faba bean soil N balance (11 g N m^?2) after harvest indicated that more soil mineral N may have been available for subsequent cereals. However, the plant available N may have been taken up by the grass dominated grass-clover catch crop which together with microbial N immobilization and N losses could leave limited amounts of available N for uptake by the subsequent two cereal crops.     

废旧锂离子电池正极有价金属的分离和提取方法

介绍了废旧锂离子电池回收处理的意义和必要性,对溶剂萃取法、化学沉淀法、电沉积法、络合离子交换法等提取和分离正极中钴、铝、镍、锂等有价金属的研究现状进行了评述。     

Biocompatibility of polyglycidol with human peripheral blood mononuclear cells

Polyglycidol (PGly), a hyperbranched water‐soluble polyether with numerous terminal hydroxyl groups, has structural similarities with polyethylene glycol. Our laboratory is exploring drug delivery using hyperbranched PGly‐cytokines conjugates. Using human peripheral blood mononuclear cells and a tumor derived human B cell line, HBL‐1; various PGly concentrations were tested for cytotoxicity. Our data indicated that hyperbranched PGly was similar in toxicity to PEG 8000, a commercial polymer. It was concluded that hyperbranched PGly did not exhibit significant cytotoxicity and showed promise for use as a biocompatible polymer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Photochemical degradation and toxicity reduction of methyl 1-[(butylamino)carbonyl]-1H-benzimidazol-2-ylcarbamate in agricultural wastewater: Comparative study of photocatalysis and sonophotocatalysis

Photochemical degradation and relative toxicity reduction of agricultural wastewater contaminated with methyl 1-[(butylamino)carbonyl]-1H-benzimidazol-2-ylcarbamate (benomyl) by the sonophotocatalytic system was compared with that of the photocatalytic system. Under the optimal conditions, i.e., initial benomyl concentration was 3.2 mg/L, the concentration of TiO₂ was 2 g/L and H₂O₂ concentration was 1.5 mM, the degradation rates with a sonication/UV/TiO₂ system was about 1.5 times higher than with a UV/TiO₂ system and sonication/UV/TiO₂/H₂O₂ system was about 1.3 times higher than with a UV/TiO₂/H₂O₂ system, respectively. Furthermore, the relative toxicity with a sonophotocatalysis was about 18% lower than with a photocatalysis within a reaction time of 120 min.     

The application of ozonation for the detoxification and biodegradability improvement of a textile auxiliary: Naphtalene sulphonic acid

From the environmental point of view, the textile industry dealing with operations such as fibre and fabric preparation, dyeing, finishing, printing etc. can be identified among the very chemical intensive sectors. Therefore the characterisation and management of textile auxiliaries within aqueous dyehouse effluents are becoming a challenging responsibility for the textile manufacturer. Although there is much speculation about the types and quantities of these chemicals released to the environment during textile manufacturing, there are only few data about the behaviour of these chemicals both in receiving water bodies and in wastewater treatment systems. Besides current understanding of industrial pollution control emphasizes the relevance of segregated stream management. This issue gains a further importance when segregated effluent streams containing auxiliaries with xenobiotic nature are considered.In this context the objective of the present study is to investigate the effect of ozonation on the toxicity and biodegradability of a naphthalene sulphonic acid derivative commonly applied in textile mills. The naphthalene sulphonic acid derivative prepared to simulate the actual situation in a dyebath discharge from a textile finishing industry has a COD of 1150 mg/l and a BOD of 10 mg/l, and pH of 5.5. Due to the highly soluble characteristic of the sulphonic groups the sample is completely soluble in nature. Ozonation experiments [conducted under the following conditions: 1200 mgO₃/h and 2400 mgO₃/h both at pH 5 and pH 11; 5325 mgO₃/h at both pH 12 and at the original pH (pH = 5.5)] show that the application of 5325 mgO₃/h ozone for 30 min at original pH can be considered as the optimum condition which is further evaluated in terms of inert COD fractions and acute toxicity. According to the experimental findings, raw naphtalene sulphonic acid derivative has an inert COD content of 1027 mg/l. With ozone application of 30 min 5325 mgO₃/h at original pH the inert COD concentration can be reduced down to 295 mg/l. The molecular weight cut-off experiments indicate that 58% of the COD originates from the 10 kDa-30 kDa fraction for the raw naphtalene sulphonic acid derivative. Due to chemical degradation under ozone, the fraction with the highest COD shifted to the < 1 kDa range for the ozonated naphtalene sulphonic acid derivative. Since the results related to the acute toxicity (in 50% v/v EC values) towards the marine algae Phaeodactylum tricornutum indicate that the toxicity of the formulation under investigation is increased considerably, it is recommended to run a further investigation by the use of another chemical oxidant instead of ozone.     

茚虫威对环境生物的安全性评价

测定了农药茚虫威对蜜蜂、鹌鹑、斑马鱼、家蚕、欧洲玉米螟赤眼蜂5种环境生物的毒性,并作出了安全性评价。测定结果显示:茚虫威对蜜蜂、斑马鱼和家蚕的LC50值分别为3.54、0.374、0.449mg/L,属高毒农药;对雌、雄鹌鹑的LD50值分别为894、559mg/L,属低毒农药;对欧洲玉米螟赤眼蜂4个虫期安全系数均大于5,属低风险农药。田间使用时,必须严禁药液流入水域,以免造成对鱼的危害;必须远离桑园和蜜蜂活动区,以免造成对家蚕、蜜蜂的危害。     

框构桥自身抗渗问题分析

针对框构桥抗渗防裂混凝土施工过程中容易出现的问题,分析了其出现的原因,阐述了解决抗渗效果差的防治措施,并通过施工中注意商品混凝土的质量、混凝土的浇筑和养护、配筋率、外加剂的选择,以确保抗渗达到设计要求。     

Accelerated carbonation for treatment of MSWI bottom ash

Leaching of heavy metals from MSWI bottom ash exceeds some of the Flemish limit values for recycling the material as granular construction application. In particular, leaching of Cu, Zn and Pb often exceeds the limit value, with Cu being the most critical. In order to recycle bottom ash, treatment is therefore required. The bottom ash studied was divided on-site into four fractions using a large-scale wet sieving installation: a sludge fraction (Ø 0–0.1 mm), a sand fraction (Ø 0.1–2 mm) and two gravel fractions (Ø 2–6 and 6–50 mm). The two gravel fractions complied with the limit values after 3 months of natural ageing. The sand and sludge fraction did not reach the limit value for Cu. Four weeks of accelerated carbonation resulted in an important decrease of Cu leaching from these two fractions, although the limit value is still exceeded. In view of applying carbonation as one of the treatment methods in an integrated industrial application, two tests were additionally performed. The use of stack gas as carbonating medium was verified by setting up an accelerated carbonation experiment at the incineration plant. Also, the depth of carbonation was measured in a 10 cm thick sample of the sand fraction after different periods of treatment. After 3 months of natural ageing only the upper 4 cm underwent a significant carbonation, while after one week of accelerated carbonation the total sample was carbonated. A model was developed to predict these experimental results.     

某氧化金矿石富氧浸出试验研究

针对某氧化金矿石的特性及所处地理位置,若采用常规氰化浸出工艺,浸出16h后,金的浸出率才能达到 95％,氰化物消耗为2．03kg/t。为此,本文提出采用“富氧氰化浸出工艺”进行处理,试验表明,该工艺能显著提高浸吸速率,浸出8h后,金的浸出率96．68％,而氰化钠用量只需要常规浸出的一半。如果浸出过程中加入活性炭,金的吸附率为 99．14％。