Von Liebig in 1840, first identified the minerals primarily necessary for plant growth. The essential minerals of the soil may be listed as nitrogen, phosphorus, sulphur, potassium, magnesium, calcium and iron. These minerals must be put back to the soil to offset the losses, which result from cropping. With this propose in view, usually three types of chemical fertilizers are produced and put to the soil.
They are as follows:
1. Nitrogenous fertilizers-in the form of ammonium sulphate, urea, nitro-limestone and ammonium sulphate/nitrate;
2. Phosphatic Fertilizer-in the form of super phosphate like nitro-phosphate and ammonium phosphate; and
3. Potassium Fertilizers - in the form of potassium.
Phosphatic Fertilizer (P2O3):- This type of fertilizer is produced by using (mineral) rock phosphate as raw material. There are large deposits of rock-phosphate in Russia, the U.S.A. and in North African countries i.e. Morocco, Tunisia, Algeria and Egypt. When the rock dust is treated with sulphuric acid it produces excellent fertilizer in the form of super-phosphate or acid phosphate. Nitro phosphate and ammonium phosphate are complex varieties of phosphatic fertilizer.
Russia is by far the largest producer of super-phosphate. The U.S.A. and many countries of continental Europe are also important producers.
Potassic Fertilizer (K2O):- The potassium fertilizer Potassium is produced and is the most commonly used type of chemical fertilizer. 75% of nitrogen is now obtained from air, 20% is derived as by-product of coke-oven plant in the form of ammonium gas four-fifths of which is nitrogen and the rest of 5% is obtained from (mineral) sodium nitrate of Chile. Nitrogen thus obtained is treated with sulphuric acid to produce fertilizer. Ammonium Sulphate, Urea, Nitro-Limestone, and Ammonium Sulphate/Nitrate are a few varieties of nitrogenous fertilizers.
Derived Chemical ManufacturesThe Paper Industry. Paper is made from cellulose or fibre. Soft wood is used for coarser kinds like newsprint and printing paper. Esparto grass, sabai grass, bhaber grass, bamboo, cotton lint, rags, etc., are used for better kinds like writing paper. The raw material is reduced to a pulp with the help of caustic soda or an acid. The pulp is bleached. A filler, such as china clay, is added and the whole is then drawn out through rollers into a thin dried sheet.
The location of paper industry depends on the kind of paper and the type of the basic raw material used for the purpose. On the basis of raw materials, the products may be divided into two groups.
(1) In the first group is included newsprint and printing paper, which use wood and wood pulp as raw material.
(2) In the second group is included the writing paper which is made out of lighter raw materials, as grass, rags, cotton waste, etc.
Newsprint
Softwood of the coniferous forest is used for coarser paper manufactures like newsprint and printing paper. Only the fibrous portion of the tree is necessary for papermaking. The paper industry using wood as raw material is localized in or near coniferous forest area. Most of world's newsprint and wood-pulp industries are situated in the southern edge of the coniferous forest belt in Canada, Norway, Sweden, Finland and Russia.
Besides the supply of soft wood, these coniferous forest areas provide unique natural advantages for two other vital locational factors, namely, the supply of power and the supply of water.
From coniferous forest belt, large quantity of newsprint and wood pulp are exported to different countries of the world. Many news print industries and wood pulp using paper mills are also found to be localized in areas, away from the coniferous forest belt. They depend on imported wood-pulp which is a pure non-weight-losing raw material With local advantages of market, power supply and water, such newsprint and paper industries have developed in many countries of Europe in different parts of the United States and Japan. Canada, Finland and Sweden are the chief exporters of newsprints and wood pulp.
Locals hypothesize that the legacy of Italian blood and culture in Cologne, colonized by the Romans more than 1500 years ago, makes the people more jovial and lighthearted. Cologne is the largest city on the Rhine.
Kolsch is not only the dialect spoken here but, also the name of their own top-fermented beer. There are more than 4,000 pubs, restaurant's and brewery taverns in Cologne.
Unlike many of the world's large cities, Cologne, with a population of over a million, gets better every day, there are more things to do and see, more new and innovative buildings... more
Travel is an opportunity to learn, whether geography, languages, history or other subjects.
Cologne is situated on the beautiful Rhine River.