铁阳极电解脱色直接黄11染料模拟废水

研究采用铁为阳极电化学法处理直接黄11染料模拟废水脱色性能的影响进行研究。影响因素包括:电流密度、pH值、染料浓度和电解质浓度。研究结果表明,电流密度大有利于染料废水脱色,但能耗消耗大;初始溶液在中性条件下不仅取得很好的处理效果,而且脱色能耗较低;随着染料初始浓度增加脱色率和脱色能耗降低的趋势;随着电解质浓度升高染料脱色率下降的趋势,脱色能耗先减少,然后缓慢增大。在染料初始浓度50 mg/L、pH值为7.11、电流密度2.083 mA/cm2、电解质Na2SO4浓度0.01 mol/L、温度20℃、搅拌速度600 r/min、电解时间60min条件下,脱色率达到92.2%,脱色能耗1.709 kW.h/kg染料。     

Generation of Priority Research Questions to Inform Conservation Policy and Management at a National Level

Abstract: Integrating knowledge from across the natural and social sciences is necessary to effectively address societal tradeoffs between human use of biological diversity and its preservation. Collaborative processes can change the ways decision makers think about scientific evidence, enhance levels of mutual trust and credibility, and advance the conservation policy discourse. Canada has responsibility for a large fraction of some major ecosystems, such as boreal forests, Arctic tundra, wetlands, and temperate and Arctic oceans. Stressors to biological diversity within these ecosystems arise from activities of the country's resource‐based economy, as well as external drivers of environmental change. Effective management is complicated by incongruence between ecological and political boundaries and conflicting perspectives on social and economic goals. Many knowledge gaps about stressors and their management might be reduced through targeted, timely research. We identify 40 questions that, if addressed or answered, would advance research that has a high probability of supporting development of effective policies and management strategies for species, ecosystems, and ecological processes in Canada. A total of 396 candidate questions drawn from natural and social science disciplines were contributed by individuals with diverse organizational affiliations. These were collaboratively winnowed to 40 by our team of collaborators. The questions emphasize understanding ecosystems, the effects and mitigation of climate change, coordinating governance and management efforts across multiple jurisdictions, and examining relations between conservation policy and the social and economic well‐being of Aboriginal peoples. The questions we identified provide potential links between evidence from the conservation sciences and formulation of policies for conservation and resource management. Our collaborative process of communication and engagement between scientists and decision makers for generating and prioritizing research questions at a national level could be a model for similar efforts beyond Canada.     

Sea Snake Harvest in the Gulf of Thailand

Conservation of sea snakes is virtually nonexistent in Asia, and its role in human–snake interactions in terms of catch, trade, and snakebites as an occupational hazard is mostly unexplored. We collected data on sea snake landings from the Gulf of Thailand, a hotspot for sea snake harvest by squid fishers operating out of the ports of Song Doc and Khanh Hoi, Ca Mau Province, Vietnam. The data were collected during documentation of the steps of the trading process and through interviewers with participants in the trade. Squid vessels return to ports once per lunar synodic cycle and fishers sell snakes to merchants who sort, package, and ship the snakes to various destinations in Vietnam and China for human consumption and as a source of traditional remedies. Annually, 82 t, roughly equal to 225,500 individuals, of live sea snakes are brought to ports. To our knowledge, this rate of harvest constitutes one of the largest venomous snake and marine reptile harvest activities in the world today. Lapemis curtus and Hydrophis cyanocinctus constituted about 85% of the snake biomass, and Acalyptophis peronii, Aipysurus eydouxii, Hydrophis atriceps, H. belcheri, H. lamberti, and H. ornatus made up the remainder. Our results establish a quantitative baseline for characteristics of catch, trade, and uses of sea snakes. Other key observations include the timing of the trade to the lunar cycle, a decline of sea snakes harvested over the study period (approximately 30% decline in mass over 4 years), and the treatment of sea snake bites with rhinoceros horn. Emerging markets in Southeast Asia drive the harvest of venomous sea snakes in the Gulf of Thailand and sea snake bites present a potentially lethal occupational hazard. We call for implementation of monitoring programs to further address the conservation implications of this large‐scale marine reptile exploitation. Cosecha de Serpientes Marinas en el Golfo de Tailandia     

THE DEVELOPMENT OF THE SENEGAL RIVER BASIN: AN EXAMPLE IN INTERNATIONAL CO-OPERATION

Joint development by several states of an international river basin requires a high degree of inter-state co-operation for the solution of the political, technical, economic and legal problems involved. In their endeavour to carry out the development of the Senegal River Basin, Senegal, Mali and Mauritania have successfully resolved several of these problems by means of unprecedented co-operation. The purpose of this paper is to provide some highlights on the approach adopted by the three nations in the solution of the problems of joint ownership of hydraulic works on the Senegal River, the allocation of their benefits and costs and their financing. La mise en valeur harmonieuse par plusieurs pays du bassin d'un fleuve qui les traverse nécessite une étroite coopération entre les gouvernements de ces pays de manière à résoudre le faisceau de problèmes politiques, techniques, économiques et juridiques qui se posent. Par une coopération dont il n'existe aucun précédent, le Sénégal, le Mali et la Mauritanie ont résolu avec satisfaction plusieurs des problèmes qu'ils ont rencontré lorsqu'ils ont entrepris la mise en valeur du bassin du fleuve Sénégal. Cet article a pour but de mettre l'accent sur les points saillants illustrant les solutions apportées par les trois pays aux problèmes de la propriété con-jointe des ouvrages hydrauliques sur le fleuve Sénégal, la répartition des coüts et des avantages ainsi que leur financement. El desarrollo conjunto de una cuenca hidrográfica internacional requiere un alto grado de cooperación entre los países rivereños en la solución de los problemas políticos, técnicos, económicos y legales. En el interés de desarrollar la cuenca del río Senegal, los países Senegal, Malí y Mauritania han resuelto con éxito varios de estos problemas gracias a una cooperación que no tiene precedentes. El propósito de este artículo es resaltar algunos enfoques adoptados por las tres naciones en la solución de los problemas derivados de la propiedad conjunta de las obras hidráulicas en el río Senegal, asi como la distribución de costos, beneficios y las responsabilidades financieras.