development projects in natural water resources like rivers and lakes, specially transferring water to use in agriculture, domestic and industrial sector without considering environmental values, causes irrecoverable and irreversible damage to ecosystem and future options. if we consider the future generation and species rights, those damages and costs can be very much than we take in. the abov...

This study constructed a parameter analysis for improving the energy performance of air-cooled water chillers by altering the angle configuration of the condenser coils. The mathematical models for energy and exergy analyses of the individual components and overall system of air-cooled water chillers are presented. This study investigated the potential enhancement of performance efficiency in a...

Food aid is a critical component of the global food system, particularly when emergency situations arise. For the first time, we evaluate the water footprint of food aid. To do this, we draw on food aid data from the World Food Programme and virtual water content estimates from WaterStat. We find that the total water footprint of food aid was 10 km in 2005, which represents approximately 0.5% o...

In the southern Weddell Sea, several water masses with the capability to form Antarctic Bottom Water (AABW) meet near the continental shelf break. The internal tidal field over the continental shelf break here is of interest due to its potential to mix these waters and form AABW. A modified version of the Princeton Ocean Model (POM) was utilized to investigate the internal tidal fields generate...

Four topics were studied concerning the modeling of ground-water flow in coastal aquifers with analytic elements: (1) practical experience was obtained by constructing a ground-water model of the shallow aquifers below the Delmarva Peninsula USA using the commercial program MVAEM; (2) a significant increase in performance was obtained by implementing the theory for variable density flow in a co...

Water shows anomalies different from most of other materials. Different sceniaros have been proposed to explain water anomalies, among which the liquid-liquid phase transition (LLPT) is the most discussed one. It attributes water anomalies to the existence of a hypothesized liquid-liquid critical point (LLCP) buried deep in the supercooled region. We briefly review the recent experimental and t...

hargraves-samani method is one of the methods for calculating plant evapotranspiration that needs minimum meteorological data. in order to evaluate et-hs model in determining sugar beet crop water demand in isfahan, an experiment was conducted at research field of department of agriculture, khorasgan branch, islamic azad university, isfahan, iranin 2005. the study was based a randomized complet...

dam reservoirs supplies water resources for drinking, agriculture, and industry almost in all parts of iran. lack of proper utilization rules and unbalanced demands versus available water has led to many problems regarding to ineffective use of the water resources. precipitation and flow rate are stochastic phenomena. therefore, multi-step processes related to the water use efficiency should be...