Detection of Methamidophos in Vegetables Using a Photometric Flow Injection System

A flow injection analysis (FIA) system using immobilized acetylcholinesterase (AChE) has been used for the detection of methamidophos in vegetable extracts. Methamidophos is one of the most commonly used organophosphate insecticides in South East Asia. AChE was immobilized onto magnetic particles; using a magnetic reactor, the particles could easily be separated from the test sample. Results show that complex matrices such as vegetable extracts have no inhibitory effect on AChE activity in the FIA system. The presence of methamidophos in the extracts caused AChE inhibition. The response could be followed as an inhibition curve and the inhibition constant calculated. Results show that using 85% AChE residual activity as the detection limit, methamidophos could be detected in lettuce and cabbage at 12 and 3 mg/kg vegetable material respectively. In a simulated field situation, cabbage leaves were spiked with 20 to 40 mg/kg methamidophos, homogenized and tested in the FIA system. The corresponding methamidophos levels predicted by the experimental results came very close to the known calculated values. Data presented here suggest that it is feasible to use this system to supplement the traditional chromatographic analysis methods for methamidophos analysis.     

Environmental quality assessment of Port Blair in Andaman islands

The Andman and Nicobar archipelago comprises of about 556 small and big islands covering an area of 8493 sq. kms in the Bay of Bengal. The very remoteness of these islands from the mainland has preserved their pristine environment and spectacular natural beauty. The Andman and Nicobar Administration is going for major developmental projects to cope with the increasing needs of the people, which ultimately results in significant changes in environmental quality. This paper describes the existing environmental quality around Port Blair city, which will give baseline scenario to assess the environmental impacts due to developments in the future.In order to monitor the air quality of the region, sampling stations were selected based on the locations of various industries and domestic activities. Suspended Particulate Matter (SPM), Sulphur dioxide (SO₂) and Nitrogen Oxides (NOx) were monitored for a period of one month during winter season. In addition, micrometeorological data, viz. wind speed and direction were also recorded and analysed to obtain the representative meteorological scenario of the air basin. The monitored values of ambient air quality was found to be within the NAAQ standards of India.Similarly, noise levels were also measured at various locations viz., residential areas, commercial centres, villages, stone quarry sites and construction sites. Noise levels were found to exceed the standards at stone quarry, construction sites and other locations.Water quality studies were carried out with respect to surface and ground water. The various physico- chemical and bacteriological parameters were analysed. It was observed that the physico-chemical parameters of surface and ground water lie within the standards stipulated for Indian subcontinent except for heavy metals which exceed the limits in ground water samples. Bacteriological analysis of sea water and ground water indicate that they are contaminated with faecal matters. Further, the ground water can be used for drinking purposes only after adequate treatment.     

Bakterielle Mineralisierung von Dibenzofuran,Dibenzo-p-dioxin und 1,2,4,5-Tetrachlorbenzol in Böden

Quantitative degradation of dibenzofuran (DBF), dibenzo-p-dioxin (DBD), and 1,2,4,5-tetrachlorbenzene (TeCB) by the bacterial strains sphingomonas sp. HH 69, sphingomonas sp. RW1 and pseudomonas sp. PS 14 was investigated by radio-tracer techniques in liquid cultures and especially in samples of different soils. Pure strains converted DBF, DBD and TeCB up to 80% to CO₂ within few days. This degradation occurred not only in aerated liquid cultures but also in heterogeneous soils, with low levels of other pollutatns at favourable pH-values. Rate and degree of the mineralization of DBF, DBD and TeCB were independent of the DBF-, DBD-, or TeCB-concentration in the soils within a broad range. There was obviously a close correlation between the starting concentration of active cells (starting bacterial count) and the rate of degradation of the test substances in soil; by raising the starting bacterial count in the soil samples, mineralization of DBF, DBD, and TeCB, respectively, was clearly accelerated. However, under nearly the same coniditions in more acid soils (pH-values < 4) no significant degradation of DBF, DBD, and TeCB to CO₂ took place. As expected, this difficulty can be overcome by mixing CaCO₂ into the acid soils (liming). Easily utilizable substances like peptone, triolein, and glucose added as special carbon and energy sources to low contaminated soils, had only a small—if any—effect on the mineralization of DBF, DBD, and TeCB. In soils contaminated by a mixture of pollutants, the bacterial strains could develop their degradation capacity only to a limited extent and showed different degradation effects depending on the basic type of contamination. The efficiency of the degradation specialists was thus dependent on the “Chemical Environment” (type and concentration of contaminants present).     

不同类型国家资源战略实施的启示及我国资源战略的选择

资源战略是经济发展战略的重要组成部分。不同的国家有着不同的资源战略。本文通过对不同类型国家资源战略实施成败的分析，从中总结了３点有益的启示：①世界经济发展中的相互依赖越来越强；②资源战略的选择要符合本国的实际；③经济结构要多样化。本文还对我国高耗、低效、封闭式的资源战略的形成作了深入的分析，并提出了我国资源战略选择的４个主要方面：①多样化是中国资源战略的出发点；②充分利用国内资源，积极利用国外资源是我国资源战略的核心；③保护资源与环境是我国资源战略的重要组成部分；④建立资源节约型国民经济体系，是我国资源战略的目标。     

Growth pattern andβ-dimethylsulphoniopropionate (DMSP) content of green macroalgae at different irradiances

Growth rates and intracellular-dimethylsulphoniopropionate (DMSP) concentrations of five green algal species collected from different geographic regions in 1986 and 1989 were determined under four photon flux rates. InUlothrix implexa, U. subflaccida andAcrosiphonia arcta from Antarctica, growth was light-saturated at lower irradiances than in temperateUlva rigida from Southern Chile andBlidingia minima from Germany. The DMSP content ofUlothrix implexa, A. arcta andUlva rigida was directly correlated with the light factor: with increasing irradiance, algal DMSP level increased. In contrast, inUlothrix subflaccida andB. minima DMSP concentrations gradually decreased up to a photon flux rate of 30µmol m^–2 s^–1, then increased markedly under the highest photon flux rate tested. In non-growing, dark-incubatedA. arcta DMSP content was reduced by 35%, while the DMSP pool of all other species remained unchanged, at the level of pre-culture conditions. Under full darkness all plants exhibited a significantly higher DMSP concentration compared with algae grown at low photon flux rates of 2 to 30µmol m^–2 s^–1. These data show a correlation between growth pattern and DMSP biosynthesis, and may point to a species-specific minimum amount of light energy necessary for DMSP accumulation.Contribution no. 302 of the Alfred Wegener Institute of Polar and Marine Research     

创建新模式实现企业安全管理全面转变

陕西精密合金股份有限公司(陕精集团)在吸取国内外现代安全管理经验基础上,创建了以事故“零”为目标,以责任制为保证,以双标(标准作业、标准化班组)为基础,以全员培训、全面管理、全线预防为对策的“连环式安全管理工作法”。实践证明,实行这一工作法成效显著,陕精集团实现连续十年工亡事故为“零”,千人负伤率逐年下降0.06。自1996年以来,陕精集团先后荣获冶金部、陕西省、西安市各项奖励26项次。此工作法在冶金行业、西北地区得到推广,成为厂长、经理安全资格培训的指定内容。     

Bio fuel ash in a road construction: impact on soil solution chemistry

Limited natural resources and landfill space, as well as increasing amounts of ash produced from incineration of bio fuel and municipal solid waste, have created a demand for useful applications of ash, of which road construction is one application. Along national road 90, situated about 20 km west of Sollefteå in the middle of Sweden, an experiment road was constructed with a 40 cm bio fuel ash layer. The environmental impact of the ash layer was evaluated from soil solutions obtained by centrifugation of soil samples taken on four occasions during 2001–2003. Soil samples were taken in the ash layer, below the ash layer at two depths in the road and in the ditch. In the soil solutions, pH, conductivity, dissolved organic carbon (DOC) and the total concentration of cations (metals) and anions were determined. Two years after the application of the ash layers in the test road, the concentrations in the ash layer of K, SO₄, Zn, and Hg had increased significantly while the concentration of Se, Mo and Cd had decreased significantly. Below the ash layer in the road an initial increase of pH was observed and the concentrations of K, SO₄, Se, Mo and Cd increased significantly, while the concentrations of Cu and Hg decreased significantly in the road and also in the ditch. Cd was the element showing a potential risk of contamination of the groundwater. The concentrations of Ca in the ash layer indicated an ongoing hardening, which is important for the leaching rate and the strength of the road construction.     

Reuse of textile effluent treatment plant sludge in building materials

This study examines the potential reuse of textile effluent treatment plant (ETP) sludge in building materials. The physico-chemical and engineering properties of a composite textile sludge sample from the southern part of India have been studied. The tests were conducted as per Bureau of Indian Standards (BIS) specification codes to evaluate the suitability of the sludge for structural and non-structural application by partial replacement of up to 30% of cement. The cement-sludge samples failed to meet the required strength for structural applications. The strength and other properties met the Bureau of Indian Standards for non-structural materials such as flooring tiles, solid and pavement blocks, and bricks. Results generally meet most ASTM standards for non-structural materials, except that the sludge-amended bricks do not meet the Grade NW brick standard. It is concluded that the substitution of textile ETP sludge for cement, up to a maximum of 30%, may be possible in the manufacturing of non-structural building materials. Detailed leachability and economic feasibility studies need to be carried out as the next step of research.