资源 标记: Vita
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1990-01-01 Strong, water-resistant casein glue, which produces joints as strong as or stronger than most of the common species of wood, is made from skim milk and common chemicals. Casein glue joints are water-resistant but not waterproof. They will withstand occasional soaking, but if soaked and dried,...
- 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,...
- 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...
- 1990-01-01 This manual is designed to assist those who plan and implement small-scale agricultural projects. By promoting awareness of environmental concerns, the manual can increase the development worker's ability to design projects that are both environmentally sound and potentially more sustainable....
- 1985-01-01 Swine production provides red meat for the human diet, uses less feed than is required to produce beef or lamb, and is also a source of bides and cooking fat. Swine are also scavengers, and can make productive use of many materials that would otherwise be wasted. Pigs (young swine of either sex...
- 1985-01-01 Multiple cropping, simply defined, is the growing of two or more crops on the same field during the same year. When the crops are grown one after another the term "sequential cropping" is applied. If the second or later crops are the result of regrowth of the first crop, then the term "ratoon...
- 1989-01-01 This paper examines the complex nature of pest problems and evaluates both chemical and nonchemical controls. The objectives of IPM are assessed, together with its current accomplishments and its future as a pest-control strategy. Although the paper emphasizes agriculture, the concepts and...
- 1984-01-01 The purpose of soil preparation is to develop a planting medium that will foster the best possible growth of agricultural crops while preventing the deterioration of the land through erosion, destruction of soil structure, or nutrient loss. The soil preparation system used must be economical,...
- 1984-01-01 This paper discusses the general theory involved in recycling agricultural wastes and several popular methods. It does not present detailed practical examples. It is important to stress that the choice of recycling method will depend on the type of waste available and on the end use the farmer...
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1980-01-01 This book is one of a series of manuals on renewable energy technologies. It is primarily intended for use by people in international development projects. The construction techniques and ideas presented here are, however, useful to anyone seeking to become energy self-sufficient. 80 pages,...