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.
Causes of Vitiligo. Melanin is the pigment that gives the skin its characteristic color. Vitiligo is caused by a loss of pigment in the skin, due to destruction of pigment-forming cells known as melanocytes. The exact cause of the destruction of these cells is not known. One possible explanation might be that the body's immune system destroys the cells, as in other autoimmune conditions.
Below are some frequently asked questions about Vitiligo. Vitiligo or leukoderma is a chronic skin condition that causes loss of pigment, resulting in irregular pale patches of skin. The precise etiology of the disease is complex and not fully understood. return to the FAQs index. 1  1.he spots occur when pigment cells, or melanocytes, are destroyed and the pigment melanin can no longer be produced. Melanocytes normally occur throughout the skin, and in the hair follicles, mouth, eyes, and some parts of the central nervous system. In Vitiligo, pigment cells can be lost in any of these areas.