Hg arc lamps

The proton NMR spectrum shows chem shifts of 6.93 5.957- (Ref 1). Photolysis with a Hg arc lamp gives N, nitrous oxide, methane, and ethane (Ref 2). It was found to produce colon and rectal carcinomas in rats after oral administration at 12mg/kg weekly, induction period 235 days (Ref 3)... 

Key , before photolysis ------, after 3.3 min irradiation with an unfiltered Hg arc lamp placed... 

Hg arc lamp and Balzers 367-nm filter about 14 cm from the center of the cryostat. (Where the curves are indistinguishable, only the dotted curve is shown.) For clarity, the noise has been omitted from the left curve. The feature marked with an asterisk ( ) is assigned to Cr(CO)h(N (Reproduced with permission from Ref. 33. Copyright 1980, Royal Society of Chemistry.)... 

Table II. Measured and Fitted Parameters Obtained in Studies of the Photodissolution of f-FeOOH Suspended in pH 4, 0.01M NaCl Containing Various Organic Acids. Illumination provided by a Hg arc lamp source and 365 nm band-pass filter (total radiation output 85 pE cm-2 min- ).

Abe et al. (1999) illuminated an aqueous suspension of TiO /Pt with an Hg arc lamp and observed production in the absence of production. An unspecified elemental analysis excluded carbonaceous contaminants, and the source of the electron donor was concluded to be Ti" " cations (Abe et al., 1999). 

Surface fluorescence of NADH/NADPH can be recorded continuously with a DC fluorimeter and correlated with changes in experimental conditions. A mercury arc lamp (with a 340-375 nm filter in front) is used as a hght source for fluorescence excitation. The fluorescence response of reduced NADH/NADPH was measured at 450-510 nm. The DC fluorimeter and the Hg arc lamp are connected to the kidney by a trifurcated fiber optics light guide. NADH/NADPH fluorescence emission can be corrected for changes in tissue opacity by a 1 1 subtraction of reflectance changes at 340-375 nm from the fluorescence. To determine NADH/NADPH redox state of the total surface area of kidney cortex and to evaluate whether certain areas were insufficiently perfused, fluorescence photographs of the total surface area were taken. The study demonstrated that the surface fluorescence method is simple and provides specific information about the mitochondrial oxidation-reduction state. 

Microbial oxidation of D-glucose gives calcium 2,5-diketo-D-gluconate (145) whose hydrazones (146) are converted to the betaines 148 by acid-catalyzed decarboxylation and cyclodehydralion (Scheme 6). ° Derivatives of these stable crystalline compounds have also been prepared by (i) methylation (Me2SO4) of 4-hydroxypyridazines (143) and (ii) thermal elimination of methyl iodide from 5-methoxy-l-methylpyridazinium iodides (144). 2 Irradiation of the mesomeric betaines (148) in ethanol (Hg arc lamp)... 

Surprisingly, the monoalkylated products (2) resist acid-catalyzed hydrolysis, but can be converted into aldehydes by irradiation in dioxane-water with a low-pressure Hg arc lamp, usually in the presence of NaHC03. Yields are in the range 25-70%. 

Similar studies34 with ethane as a feed led to yields of CH3CHO of 11 i mol/hr, 3 p mol/hr HCHO, and 5 p mol/hr CO2 on irradiation and no products again without irradiation. Data for ZnO itself showed higher selectivities to CH3CHO for unirradiated catalysts than for irradiated catalysts. Photochemical and thermal pathways are clearly different for these materials. A 200 W Hg arc lamp with broad band ultraviolet wavelengths was used for excitation. 

In another study, erytrolide A (66), isolated from the Caribbean octocoral Erythropodium caribaeorum, is considered to originate in nature from terpenoid 65 by a DPM rearrangement, probably the first observation of the involvement of this photoreaction in the production of natural products [47]. In order to test this possibility, compound 65 was irradiated in benzene for 3 h, using a medium-pressure Hg arc lamp, affording 66 in 87%... 

FIGURE 2 Vertical etch profile produced by PEC etching of n-type GaN using KOH solution and Hg arc lamp illumination [23]. 

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