Light with zinc carbonate

Table V. Effect of Light and Humidity0 on Book Papers Impregnated with Zinc Carbonate...

Example hydrogen and carbon dioxide test lighted splint result with hydrogen gives ct pop result with carbon dioxide splint is extinguished a zinc carbonate and zinc chloride test ... 

This chapter covers the effect of light from a GE sunlamp (high in UV light) on papers containing zinc oxide under moist (60% relative humidity) and dry (8% relative humidity) conditions in comparison with the effects on untreated controls, the effects of iodide as a negative catalyst, and the effect of converting the zinc oxide to zinc carbonate before exposure to avoid the catalytic photochemical reaction. 

Since there was no significant difference in the loss in folding endurance between the controls with no zinc carbonate and the treated papers containing about 2% zinc carbonate when exposed to light and humidity, it is obvious that no accelerated degradation results from the zinc carbonate. 

With this demonstration that zinc carbonate does not catalyze the photodegradation of paper in the presence of UV light and high humidity, we feel that the diethyl zinc process, as modified by the final carbon dioxide exposure, is now commercially feasible. 

The experimental details for mono-M-propylanillne are as follows. Reflux a mixture of 230 g. of aniline and 123 g. of n-propyl bromide for 8-10 hours. Allow to cool, render the mixture alkafine, and add a solution of 150 g. of zinc chloride in 150 g. of water. Cool the mixture and stir after 12 hours, filter at the pump and drain well. Extract the thick paste several times with boiling light petroleum, b.p. 60-80° (it is best to use a Soxhlet apparatus), wash the combined extracts successively with water and dilute ammonia solution, and then dry over anhydrous potassium carbonate or anhydrous magnesium sulphate. Remove the solvent on a water bath, and distil the residue from a Claisen flask with fractionating side arm (well lagged). Collect the n-propyl-aniline at 218-220° the yield is 80 g. Treat the pasty solid zincichloride with an excess of. sodium hydroxide solution and steam distil 130 g. of pure aniline are recovered. 

When a photosynthetic organism is omitted, the addition of a photosensitizer is necessary. The methods use light energy to promote the transfer of an electron from a photosensitizer to NAD(P) via an electron transport reagent [6g]. Recently, carbon dioxide cvas reduced to formic acid with FDH from Saccharomyces cerevisiae in the presence of methylviologen (MV ) as a mediator, zinc tetrakis(4-methylpyridyl) porphyrin (ZnTMPyP) as a photosensitizer, and triethanolamine (TEOA) as a hydrogen source (Figure 8.8) [6h]. 

An aqueous solution containing 300 ng/ iL trichloroethylene and colloidal platinum catalyst was irradiated with UV light. After 12 h, 7.4 ng/pL trichloroethylene and 223.9 ng/pL ethane were detected. A duplicate experiment was performed but 1 g zinc was added to the system. After 5 h, 259.9 ng/pL ethane was formed and trichloroethylene was nondetectable (Wang and Tan, 1988). Major products identified from the pyrolysis of trichloroethylene between 300-800 °C were carbon tetrachloride, tetrachloroethylene, hexachloroethane, hexachlorobutadiene, and hexachlorobenzene (Yasuhara and Morita, 1990). 

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