A two-dimensional, unsteady, isothermal and two-phase flow of reactant-product mixture in the air-side electrode of proton exchange membrane fuel cells (PEMFC) is studied numerically in the present study. The mixture is composed of oxygen, nitrogen, liquid water and water vapor. The governing equations are two species conservation, a single momentum equation for mobile mixture, liquid mass cons...

Because air-water and water-air interfaces are equally refractive, cloud droplets and microbubbles dispersed in bodies of water reflect sunlight in much the same way. The lifetime of sunlight-reflecting microbubbles, and hence the scale on which they may be applied, depends on Stokes Law and the influence of ambient or added surfactants. Small bubbles backscatter light more efficiently than lar...

Water is a finite resource that must be shared among multiple users and economic and conservation objectives can often be seen as being in conflict. We explored this perception by conducting an integrated bioeconomic analysis of irrigated agriculture and the conservation of freshwater attributes in an agricultural landscape, the Tasmanian Midlands. We constructed a simple bioeconomic model base...

Climate change, water supply limits, and continued population growth have intensified the search for measures to conserve water in irrigated agriculture, the world's largest water user. Policy measures that encourage adoption of water-conserving irrigation technologies are widely believed to make more water available for cities and the environment. However, little integrated analysis has been c...

The Conservation Effects Assessment Project was established to quantify water quality benefits of conservation practices supported by the U.S. Department of Agriculture (USDA). In 2004, watershed assessment studies were begun in fourteen agricultural watersheds with varying cropping systems, landscapes, climate, and water quality concerns. This paper reviews USDA Agricultural Research Service '...

Changes in precipitation can influence soil water and nutrient availability, and thus affect plant nutrient conservation strategies. Better understanding of how nutrient conservation changes with variations in water availability is crucial for predicting the potential influence of global climate change on plant nutrient-use strategy. Here, green-leaf nitrogen (N) and phosphorus (P) concentratio...

Water conservation is a priority in San Antonio, Austin, Dallas, and other major Texas cities that routinely face water shortages and drought. Soil management is fundamental to water conservation efforts. Incorporation of composted biosolids (CB) in low quality soils can enhance water conservation and provide organic carbon and nutrients that improve growth of vegetation and limit sediment loss...

1State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, CAS and MWR, Yangling, Shaanxi 712100, China 2University of Chinese Academy of Sciences, Beijing 100049, China 3Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China 4Department of Forestry, Mississippi State University, Starkvil...

Freshwater biodiversity is the over-riding conservation priority during the International Decade for Action - 'Water for Life' - 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100000 species out of approximately 1.8 million - almost 6% of all described species. Inland wate...