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  1. 关键资源 2001-01-01 Often the biggest challenge faced by a tropical farmer is not in the production of a crop but rather in the preservation of the crop. Farmers may want to preserve a crop for future consumption or for sale at a time when the market will offer a higher price. Using a solar dehydrator is a simple,...  
  2. 1985-01-01 Developing countries are in a particularly good position to use solar energy because so many receive an abundance of sunshine. More important, the inhabitants of these countries are frequently scattered over vast areas, making access to electricity or conventional fossil fuels difficult as well...  
  3. 关键资源 This article is from ECHO Asia Note # 37. 在亚热带和热带种子储存是一项挑战。如果没有干燥和冷环境,种子的质量可能会急剧恶化。储藏时的高温高湿会加速种子的新陈代谢并且促使食种虫增殖(Lale and Vidal, 2003; Upadhyay and Ahmad, 2011)。冰箱、除湿机和杀虫剂等技术能防止这些毁坏种子的情况发生,但是热带地区的小型农户不一定能利用这些技术。很多当地传统方式被用于防止虫害。一些处理剂通常在种子储存前添加到种子中,为了毒杀害虫,或者破坏和阻止昆虫在种子周围移动。一些处理剂能非常有效地减少害虫生长,...  
  4. 1985-01-01 Solar distillation uses the heat of the sun directly in a simple piece of equipment to purify water. The equipment, commonly called a solar still, consists primarily of a shallow basin with a transparent glass cover. The sun heats the water in the basin, causing evaporation. Moisture rises,...  
  5. This book describes the important contribution to student learning enabled by solar lamps and the books that can be studied by their light when school has finished for the day. It also gives a link to free information on how to set up and maintain a light library in your own school or community....  
  6. 1967-01-01 The VITA Solar Cooker was especially designed to be sturdy, relatively easy to make, easy to repair, and low in cost. It uses the principle of the Fresnel reflector which concentrates light and heat by using several simple reflecting surfaces. Most other cookers use a doubly-curved reflecting...  
  7. 1986-01-01 The easiest and most practical application of solar energy is for heating water. It has been technically feasible to heat household water using solar energy since the 1930's. Solar water heaters for homes and industry have been employed extensively in Israel, Australia, and Japan, and were quite...  
  8. 1985-01-01 In many equatorial regions, native trees and bushes are being cut at an alarming rate to meet the growing demands for agricultural land, industry, and fuelwood and charcoal. The environmental consequences of this deforestation are severe, ranging from soil erosion and climate changes to flooding...  
  9. 关键资源 2023-11-21 Litter systems are an approach to hygienic, integrated animal production in which animals are raised in an enclosed space on a floor of organic bedding. Systems with thick bedding material are sometimes called deep litter systems. Litter systems allow you to prioritize animal health by providing...  
  10. 关键资源 2005-01-20 The leaves of the Moringa oleifera tree are very nutritious. They can be consumed fresh, cooked or dried. Since dried Moringaleaves retain their nutrient content, it is possible to convert them into leaf powder. When there is an abundance of leaves, this leaf powder can be made and stored easily....