the use of solar collectors in combination with heat pipes is rapidly growing in recent years.heat pipes, as heat transfer components, have undeniable advantages in comparison with other alternatives. the most important advantage is their high rate of heat transfer at minor temperature differences. although there have been numerous studies on the heat analysis or first thermodynamic analysis of...

abstract water and nitrogen are the main limiting factors affecting agricultural production in arid and semiarid regions. therefore, improving the efficiency of these factors is very important. the method of fertilizer application is affecting water and fertilizer use efficiency. the objective of this study was to investigate the effect of furrow fertigation on fertilizer use efficiency (fue), ...

abstract shortage and improper distribution of rainfall in tea growing period are important growth limiting factors in tea fields in northern part of iran. if there is not any other limited factors, supplemental irrigation by sprinkler can increase tea yield. this study was carried out in order to investigate the optimum sprinkler irrigation interval on yield and water use efficiency of tea. th...

abstract due to limited water resources and occurrence of recent droughts, the use of new management and planning methods for optimal irrigation scheduling of agricultural crops is inevitable. present of appropriate mathematical and dynamic relationship between yield, evapotranspiration and water use efficiency parameters is the first and most important step in the optimal management of irrigat...

some factors affecting crude protein balance (cpb), as a measure of efficiency, were studied using 2824 records of 501 lactating holstein cows. the cpb (kg d-1) was calculated as crude protein (cp) intake (kg) minus cp yield (kg). two different statistical methods including principal components (pcs) and general linear model analyses were used to study the effects of different factors. crude pr...

degraded soils in northwest china are mostly nonproductive due to imbalanced nutrient and inadequate water supply. the effects of manure application at three different rates (7.5, 15.0, and 22.5 t ha–1) combined with chemical fertilizers on soil water and water-use efficiency in maize [compared with chemical fertilizers (control)], under semi-arid conditions in dark loessial soil and over a per...