上海市若干环境污染物的诱变性

用中国仓鼠肺成纤维细胞(V_(79)),进行次黄嘌呤—鸟嘌呤磷酸核糖转移酶位点(HGPRT Locus)试验,检测了上海市若干环境污染物的诱变性。结果发现,污染物量与诱变性之间呈剂量—反应关系。所有样品经代谢活化后(加S_9),其诱变性均有增高的趋势。卷烟焦油、油烟冷凝物的T/C值均>3,而不加S_9的黄浦江水和自来水样,则对V_(79)细胞可能具有间接的诱变作用(T/C值<3)。     

Prenatal detection of trisomy 21 in uncultured amniocytes by fluorescence in situ hybridization: A prospective study

A prospective study was undertaken to evaluate the use of fluorescence in situ hybridization (FISH) for the detection of trisomy 21 in interphase nuclei of uncultured amniotic fluid cells. Five hundred cases were analysed in situ and classified as normal or abnormal; the results were subsequently checked against the cytogenetic findings. Four hundred and ninety-three were correctly identified as normal with an 86·6 per cent average frequency of scored nuclei exhibiting two signals; six cases were correctly identified as trisomic for chromosome 21 with 81·7 per cent of scored nuclei exhibiting three signals; and one abnormal case involving an unbalanced chromosome 21·21 translocation was falsely scored as normal due to poor hybridization/detection efficiency. The method has been substantially improved and simplified so that it is suitable for the rapid detection of trisomy 21. As aneuploidy detection in interphase does not identify structural chromosome aberrations, it is not a substitute for fetal chromosome analysis.     

Biological treatment of dye wastewaters using an anaerobic-oxic system

Three dye solutions, namely, C.I. Acid Yellow 17, C.I. Basic Blue 3, and C.I. Basic Red 2, were treated in an upflow anaerobic sludge blanket (UASB) reactor followed by a semi-continuous aerobic activated sludge tank. When hydraulic retention time was about 12 hours, no significant color removal was observed in the aerobic stage. In the anaerobic stage, Acid Yellow 17, Basic Blue 3, and Basic Red 2 were removed by 20%, 72%, and 78%, respectively. To treat wastewater from a dye manufacturing factory with COD concentration of 1200 mg/l and Color of 500 degree (dilution factor), an UASB reactor (4.5 liters) and an activated sludge tank (5 liters, adjustable), COD and color were removed by more than 83% and 90% at a COD loading rate of 5.3 kg COD/m³-day in the anaerobic stage, and at the hydraulic retention time of 6-10 hours for the anaerobic stage and 6.5 for the aerobic stage. The anaerobic stage of the A/O system removes both color and COD. In addition, it also improves biodegradability of dyes for further aerobic treatment.     

缺氧反硝化-好氧串联系统对难降解PVA退浆废水的试验研究

研究了投加硝态氮NO3^--N对缺氧反硝化-好氧和缺氧水解-好氧串联系统处理印染PVA退浆废水的效果。结果表明，缺氧反硝化投加硝态氮NO3^--N比缺氧水解-好氧对CODCr的去除率在缺氧池、好氧池中均提高了30％，缺氧反硝化-好氧工艺二沉池出水经生物碳处理后，CODCr，的去除率达90％。C：N：P的比例合适与否是处理印染PVA退浆废水成功的关键。     

Model reactor for photocatalytic degradation of persistent chemicals in ponds and waste water

A laboratory scale flow-through model reactor for the degradation of persistent chemicals using titanium dioxide (TiO₂) as photocatalyst immobilized on glass beads is presented. In the test system with a volume of 18 L contaminated water is pumped to the upper part of the floating reactor and flows over the coated beads which are exposed to UV-radiation. The degradation of two dyes of different persistance was investigated. Primary degradation of methylene blue did not fit a first order kinetic due to coincident adsorption onto the photocatalyst and direct photolysis, resulting in a half-life of 6 h. A filtrate of a green algae suspension accelerated the colour removal. In contrast, reactive red 2 was degraded only by photocatalysis; neither adsorption nor direct photolysis led to a colour removal. The course of primary degradation followed a first order kinetic with a half-life of 18 h and a rate constant of 0.04 h⁻¹. Analysis of the degradation products indicated mineralization by detection of NO₂⁻ and NO₃⁻, accompanied by a decrease of pH and an increase of conductivity. A successful adaptation of the model reactor (scale 1:10) to dimensions required for surface waters and waste water treatment plants would be a costefficient and environmentally sustainable application of photocatalysis for the treatment of industrially polluted water and could be of relevance for third world contries, particularly those favoured by high solar radiation.     

长江、嘉陵江(重庆段)源水有机提取物的类雌激素活性评价

为了解长江、嘉陵江(重庆段)源水有机提取物的类雌激素活性，分别于夏季和冬季采用GDX—120大孔树脂对位于城区上、中、下游5个断面长江、嘉陵江(重庆段)源水进行有机物的浓缩提取。用体外MCF—7细胞增殖试验检测有机提取物的类雌激素活性。结果显示，源水有机提取物均具有类雌激素活性。其类雌激素活性中、下游均高于上游，丰水期高于枯水期。     

相变储能光伏太阳能热泵干燥系统的研究

建立了相变储能光伏太阳能热泵干燥系统实验平台,介绍了系统的运行方式以及太阳能光伏集热蒸发器与直流压缩机的匹配计算,最后对实验数据进行了分析。结果表明,太阳能辐照量为800 W/m~2、光伏集热蒸发器面积为12 m~2的条件下,系统制热功率为10 k W,太阳能光伏集热蒸发器发电量为6.2 k W·h,大于直流压缩机的耗电量,满足供电要求;实验所得系统COP为3.25。相变储能可以解决太阳辐照波动导致的系统运行不稳定问题,具有显著的节能性和环保性。     

钛酸铋光催化降解水中酸性大红的研究

采用异丙醇助水热法制备了钛酸铋光催化剂,UV-vis漫反射测试表明其光吸收带较TiO2发生了红移,通过多点BET法计算出其比表面积为14.16m2/g,平均孔径为21.05nm。以酸性大红为模拟污染物,在三相内循环流化床光催化反应器中进行光催化反应,研究了废水的pH值以及钛酸铋投加量对酸性大红脱色率的影响。结果表明:废水的pH=3.0,催化剂投加量为0.1g/L是最佳反应条件;当流量为10L/h时,连续运行3h后,酸性大红染料的去除率可达92.0%;当处理水量增大时,经过两级处理,酸性大红染料的总去除率仍可达到94.4%。     

Perceptions towards solar mini‐grid systems in India: A multi‐stakeholder analysis

This study identifies and assesses the perspectives of four key stakeholder groups towards solar minigrids in rural India. The stakeholders considered are policymakers, minigrid developers and operators, development organizations, and national grid representatives. Recent state and national policies in India have increased the focus on minigrids and their services. In this study, stakeholder interviews were employed to identify the attitudes towards the recent electricity policy, the underlying context for minigrid development, the role of minigrids in rural electrification, and the inclusion of minigrid systems within the larger framework of electricity sector policies by the recent government minigrid policies. Results indicate that stakeholders agree that minigrids, as a rural electricity service, are currently viable to complement the national grid due to their high reliability, performance in remote regions, and diminishing cost per unit. However, stakeholders disagree on the future outcomes, with diverging views on the priority of minigrids as an electrification tool in the face of the expanding central grid, the ideal implementation strategy for minigrids, and the potential for grid‐minigrid interaction. Based on stakeholder feedback, the growth of minigrids in India is likely to be constrained by the confidence in recent policies, necessitating more frequent dialogue among decision makers and a solidified relationship to the national electricity grid.     

Experimental investigation on effect of an absorber plate covered by a layer of sand on the efficiency of passive solar air collector

A passive flat-plate solar air collector was constructed in the laboratory of New and Renewable Energy in Arid Zones, Ouargla University, South East Algeria. The absorber of the passive flat-plate solar air collector was laminated with a thin layer of local sand. This acted as a thermal packed bed with a collecting area of 0.5 m² (1 m × 0.5 m). Three series of experiments were performed. The first consisted of choosing the best sand brought from three different places of the Algerian desert. The second consisted of studying the effect of the thickness of the sand layer on the daily efficacy of the collector. The influence of the sand diameter was investigated in the third series. The experimental results showed that: All collectors covered with sand had higher efficiency than those without. It was noticed that, for a fixed mass of sand (given thickness of the sand layer), the improvement of the collector was inversely proportional to the sand particle diameters. The maximum efficiency approximates 62.1% for a particle diameter 0.063 mm, compared to 41.71% for a diameter 0.250 mm.The efficiency of the collector for a fixed particle diameter increases with the increase in the thickness of the sand layer. The collector with thickness sand layer 0.84 mm gave the best efficiency of 46.14% compared to 27.8% for 0.28 mm of thickness sand layer.