1 Therefore, the idea is to use a set of optimum conditions to get the most efficient yield of ammonia and this involves getting a low % yield (e.g. 8% - 15% conversion) but fast. 2  Described below are the conditions to give the most economic production of ammonia.
A Dr. Mehmet Oz, MD , Cardiology (Cardiovascular Disease), answered. The white patches caused by the skin condition vitiligo can spread to other locations or can stay in one area. The course is unpredictable and varies from person to person. Some people with vitiligo say that new patches form on skin that is under pressure or exposed to friction. This can happen from shaving or rubbing from jewelry or clothing.
The cause is not known. Vitiligo may be an autoimmune disease. These diseases happen when your immune system mistakenly attacks some part of your own body. In vitiligo, the immune system may destroy the melanocytes in the skin.It is also possible that one or more genes may make a person more likely to get the disorder. Some researchers think that the melanocytes destroy themselves. Others think that a single event such as sunburn or emotional distress can cause vitiligo.he disorder affects all races and both sexes equally, however, it is more noticeable in people with dark skin. People with certain autoimmune diseases (such as hyperthyroidism) are more likely to get vitiligo than people who donât have any autoimmune diseases.