Water quality induced corrosion of stainless steel valves during long-term service in a reverse osmosis system

The current study analyzes the contribution of 10 water quality parameters(including pH,turbidity,conductivity,total dissolved solids(TDS),hardness,total organic carbon(TOC),alkalinity,calcium ions,chlorides and sulfates) to corrosion extent of stainless steel valves taken from different locations in a reverse osmosis system of a reclaimed water plant.The valves were in service for 5 years.Raman spectroscopy and X-ray photoelectron spectroscopy analyses are conducted to quantify corrosion produc...     

Nuclear Wastes in the Arctic Ocean. the Consequences of Past Dumping and Opportunities for Future Prevention

The view is expressed that the assessment of disposal of nuclear waste in the ocean (specifically the Arctic and Kara Seas) is critical to understanding Arctic pollution. Much needs to be done in deciding what we should do, even though many wastes are long-standing and persistent. in 1993, disclosures about Russian dumping of submarine nuclear reactors, nuclear fuel, and other radioactive wastes into the Arctic Ocean brought this region and its problems into the world spotlight and raised public concerns about the resulting health and environmental risks. As a result of this concern, the Congressional Office of Technology Assessment published a 1995 study, Nuclear Wastes in the Arctic (US Congress Office of Technology Assessment, 1995). This paper summarises and updates that study.     

Matching biodiversity indicators to policy needs

At the global scale, biodiversity indicators are typically used to monitor general trends, but are rarely implemented with specific purpose or linked directly to decision making. Some indicators are better suited to predicting future change, others are more appropriate for evaluating past actions, but this is seldom made explicit. We developed a conceptual model for assigning biodiversity indicators to appropriate functions based on a common approach used in economics. Using the model, indicators can be classified as leading (indicators that change before the subject of interest, informing preventative actions), coincident (indicators that measure the subject of interest), or lagging (indicators that change after the subject of interest has changed and thus can be used to evaluate past actions). We classified indicators based on ecological theory on biodiversity response times and management objectives in 2 case studies: global species extinction and marine ecosystem collapse. For global species extinctions, indicators of abundance (e.g., the Living Planet Index or biodiversity intactness index) were most likely to respond first, as leading indicators that inform preventative action, while extinction indicators were expected to respond slowly, acting as lagging indicators flagging the need for evaluation. For marine ecosystem collapse, indicators of direct responses to fishing were expected to be leading, while those measuring ecosystem collapse could be lagging. Classification defines an active role for indicators within the policy cycle, creates an explicit link to preventative decision-making, and supports preventative action.     

Comparing Scales of Environmental Effects from Gasoline and Ethanol Production

Understanding the environmental effects of alternative fuel production is critical to characterizing the sustainability of energy resources to inform policy and regulatory decisions. The magnitudes of these environmental effects vary according to the intensity and scale of fuel production along each step of the supply chain. We compare the spatial extent and temporal duration of ethanol and gasoline production processes and environmental effects based on a literature review and then synthesize the scale differences on space–time diagrams. Comprehensive assessment of any fuel-production system is a moving target, and our analysis shows that decisions regarding the selection of spatial and temporal boundaries of analysis have tremendous influences on the comparisons. Effects that strongly differentiate gasoline and ethanol-supply chains in terms of scale are associated with when and where energy resources are formed and how they are extracted. Although both gasoline and ethanol production may result in negative environmental effects, this study indicates that ethanol production traced through a supply chain may impact less area and result in more easily reversed effects of a shorter duration than gasoline production.