Light heating effect

This problem involves consideration as to the effect of external conditions such as light, heat, moisture, altitude, manuring and other cultural matters, and as is obvious, such considerations may, and do, vary greatly with different plants. Such considerations are to some extent within the scope of the knowledge and skill of the well-trained farmer and the careful distiller. But there are other considerations of a much more abstruse character to be taken into account, and here only the chemist can undertake the necessary investigations. The questions which present themselves for solution are, broadly, some such as the following —... 

I. Feugt, Stabilization of Synthetic Polymers Against Light and Heat Effect, Chemistry Publishers, Leningrad, p. 26-29 (1972). 

This paper discusses the effects of the pyrolysis of wood and paper treated with pentachlorophenol or sodium pentachlorophenate along with the exposure of sodium pentachlorophenate to ultraviolet light. The effect of heat, light, and air with respect to some of the chlorinated dibenzo-p-dioxins will be considered. 

Paraffins react with chlorine under the influence of light, heat, or catalysts to form chlorocarhons. The chlorocarhons are important in industry because of their own properties and because of their use as chemical intermediates in the synthesis of other compounds. Today, many of the chlorocarbons are regulated by federal and state agencies to limit their use because of detrimental effects on health and the environment. 

This is caused by the effect of air on an ether. This is classed as a radical reaction as the effects of light, heat and radical sources demonstrate. The general reaction can be written ... 

Some effects of irradiation on vitamins have been mentioned earlier. It appears that irradiation and heat treatment affect vitamins differendy. Apparendy, vitamins Br B6, B12 and folic acid decompose less under as high a radiation dose as 60 kGy than under autoclaving at 120°Cfor 20 minutes. On the other hand, vitamin C is much more sensitive to irradiation. Generally, the radiosensitive vitamins are also sensitive to light, heat, and oxygen. In fresh foods, the vitamins that are most susceptible to irradiation are A and E. There is also some decomposition of vitamins B, and C. Other vitamins are fairly stable under irradiation. However, for the most part, the vitamins are more susecptible to heat treatment than to irradiation. 

This form of approach is probably the only way to deal with multiple agents, for example where contaminants are added to the normal weathering factors of light, heat and water, and it can be extended to include synergistic effects. However, this quickly becomes very complicated and attempts at such analysis are not common. 

Peroxides are a very common impurity in many excipients, particularly polymeric excipients [56]. They are used as initiators in polymerisation reactions, but are difficult to remove. Ding [57] monitored the peroxide concentrations within polysorbate 80 solutions, and demonstrated the effect of light, heat and concentration on peroxide concentrations. The author showed that the peroxide concentrations increased 9-fold at the lowest polysorbate concentration versus increases of only 1.5-fold at the highest polysorbate concentration. However, the absolute peroxide levels at the higher concentration were much higher. 

Pyrotechnic mixtures An oxidizer/fuel mixture that produces bright or colored lights, heat, fogs, or acoustic effects. 

Another approach to induce the volume phase transition by photoirradiation utilizes the direct heating effect of the gel by light [20]. Gels containing... 

---