UV-ozonolysis

More recently, NIST researchers [13, 19] developed a device to more precisely generate surface energy libraries using OV-ozonolysis. Pictured in Fig. 5, this device achieves graded UV-ozonolysis through a computer-driven translation stage. 

Fig. 4 Water contact angle data (a) and surface energy data (b) from a surface energy library produced through the graded UV-ozonolysis of an ODS self-assembled monolayer on sihcon. (Reproduced with permission from [17])...

Fig. 3.5 Fabrication of pp specimens for SPM calibration. The first step (1) comprises soft-lithography of appropriate SAM molecules onto a planar substrate. A composite stamp, which has both flat and corrugated areas, allows printing of the comb-patterned strip with the adjacent solid calibration field. Next, a graded UV-ozonolysis (UVO) systematically modifies the chemistry of the patterned SAM (and calibration field) along one direction (3). For example, methyl-terminated alkyl chain SAMs (hydrophobic) can be gradually converted into carboxylic acid terminated (hydrophilic) chains. Subsequent filling with a hydrophilic SAM completes the matrix of the specimen (2fA...

UV-ozonolysis and UV-peroxide have both been shown to be effective for decomposition of dilute solutions of explosives. The major drawbacks are the slow degradation rate, and high costs. 

Vinyl chloride can be completely oxidized to CO2 and HCl using potassium permanganate [7722-64-7] in an aqueous solution at pH 10. This reaction can be used for wastewater purification, as can ozonolysis, peroxide oxidation, and uv irradiation (42). The aqueous phase oxidation of vinyl chloride with chlorine yields chloroacetaldehyde (43). 

Ocimene is a pleasant-smelling hydrocarbon found in the leaves of certain herbs. It has the molecular formula C10Hi6 and a UV absorption maximum at 232 nm. On hydrogenation with a palladium catalyst, 2,6-dimethyloctane is obtained. Ozonolysis of /3-ocimene, followed by treatment with zinc and acetic acid, produces the following four fragments ... 

Hydrocarbon A, CLoIi14, has a UV absorption at Araax = 236 nm and gives hydrocarbon B, C10Hig, on catalytic hydrogenation. Ozonolysis of A followed by zinc/acetic acid treatment yields the following diketo dialdehyde ... 

Chemical/Physical. Ozonolysis of acetic acid in distilled water at 25 °C yielded glyoxylic acid which oxidized readily to oxalic acid before undergoing additional oxidation producing carbon dioxide. Ozonolysis accompanied by UV irradiation enhanced the removal of acetic acid (Kuo et al, 1977). 

The (Z)- and ( )-styrylpyrazine structures 20j and 20k were assigned on the base of the mass, NMR, and UV spectral data. The mass spectrum of Z isomer (20j) shows a base peak (the molecular ion) at m/z 210 with a peak at m/z 133 formed by the loss of a phenyl group firom 20j. The H-NMR spectrum shows the presence of five aromatic and two olefinic protons in addition to one heteroaromatic proton and two methyl groups attached to the heteroaromatic nucleus. Ozonolysis of the Z isomer (20j) yields 3-formyl-2,5-dimethylpyrazine (487) and benzaldehyde, confirming the styryl moiety in 20j. The ( )-styryl derivative (20k) is readily isomerized to the Z isomer (20j) on exposure to sunlight (Scheme 60). Extraction of the pyrazines from I. humillis in the dark indicates that E isomer 20k is the naturally occurring product 144,145). 

Vinylsilanes, ozonolysis, 275-6 Vimses, ozone disinfection, 616 Visible spectrophotometry see UV-visible spectrophotometry... 

Problem 12.10 Each of three C H, isomers absorbs 2 mol of H to form n-hexane. COj and RCOOH are not formed on ozonolysis from any of the compounds. Deduce possible structures for the 3 compounds if their uv absorption maxima are 176. 211, and 216 nm. ... 

Jain (Ref 96) found that ozonization of RDX dissolved in w is enhanced by concurrent exposure to UV radiation. It is claimed that a flow system based on this combined photolysis-ozonolysis can provide a cost-effective method of RDX removal from munition industry waste waters... 

Smetana et al (Ref 1 IS) used a scheme previously developed for eliminating TNT from pink water to show that combined photolysis-ozonolysis effectively degrades RDX in aq solns to gaseous products. The photolytically active region is in the UV at 254,300 and 350nm wave lengths... 

The UV/ozone process destroyed about 75% of the influent anthracene within about 2 min. The degradation rate was generally steady for about the first minute of treatment but decreased somewhat thereafter, perhaps indicating the buildup of scavengers reacting with hydroxyl radicals. The UV / ozone process decelerates the chemical reaction of the ozonolysis of anthracene with molecular ozone as compared with ozone treatment alone (Trapido et al., 1995). 

In other examples the p substituent was ascertained by ozonolysis of the double bond and comparison of the UV spectra of the resultant aldehyde with that of p-methoxybenzaldehyde (18-20). 

UV peroxide process Ozonolysis Peroxon process Fe3+-catalyzed photolysis Photoassisted Fenton process Photocatalysis... 

When aqueous solutions are treated with ozone for several hours, there is significant sample evaporation the rate of this process depends on the initial sample volume and the average temperature of the sample during the period of ozonolysis. The time required for ozone application is considerably longer than that needed with other AOPs, such as UV irradiation. 

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