Trapping studies

Sediment trap studies in the open ocean show that the flux of organic carbon at any depth is directly proportional to the rate of primary productivity in the surface water and inversely proportional to the depth of the water column (Suess, 1980) ... 

Hosokawa, C., Yoshikawa, H. and Masuhara, H. (2004) Optical assembling dynamics of individual polymer nanospheres investigated by singleparticle fluorescence detection. Phys. Rev. E, 70, 061410-1-061410-7 (2005) Cluster formation of nanoparticles in an optical trap studied by fluorescence correlation spectroscopy. Phys. Rev. E, 72, 021408-1-021408-7. 

Lai, C.S. and Piette, L.H. (1978) Spin-trapping studies of hydroxyl radical production involved in lipid peroxidation. Arch. Biochem. Biophys. 190, 27-38. 

Albano, E., Lott, K.A.K., Slater, T.F., Stier, A., Symons, M.C.R.and Tomasi, A. (1982). Spin trapping studies on the free radical products formed by metabolic activation of carbon tetrachloride in rat liver microsomal fractions, isolated hepato-cytes and in vivo in the rat. Biochem. J. 204, 593-603. 

Connor, H.D., Gao, W., Nukina, S., Lemasters, J.J., Mason, R.P. and Thurman, KG. (1992). Evidence that free radicals are involved in graft failure following orthotopic liver transplantation in the rat an electron paramagnetic resonance spin trapping study. Transplantation 54, 199-204. 

Weinert, E. E. Rokita, S. E. Kinetic and trapping studies of 2 -deoxynucleoside alkylation by a quinone methide. Chem. Res. Toxicol. 2005, 18, 1970-1970. 

Secondary Photochemical Processes. While the nature of the primary photochemical step may be described as still uncertain, the nature of the subsequent secondary steps is best characterized as obscure. A previous trapping study during exhaustive irradiation (30) demonstrated that silylenes are formed somewhere along the line and implicated silyl radicals as well since the formation of Si-H bonds was observed, presumably by hydrogen atom abstraction. 

Misik V, Miyoshi N, Riesz P (1995) EPR spin-trapping studies of the sonolysis of H2O/D2O mixtures probing the temperatures of cavitation regions. J Phys Chem 99 3605-3611... 

J. Vasquez-Vivar, N. Hogg, K.A. Pritchard, and B. Kalyanaraman, Superoxide anion formation from ludgenin an electron spin resonance spin-trapping study. FEBS Lett. 403, 127—130 (1997). 

Hydroxyurea reacts with oxy, deoxy and metHb in vitro to form iron nitrosyl hemoglobin (HbNO) and transfers NO to 2-6% of the iron heme groups [115]. Trapping studies using cyanide and carbon monoxide indicate that hydroxyurea oxidizes both oxy and deoxyHb to metHb and reduces metHb to deoxyHb specifically identifying the reaction of hydroxyurea and metHb as the critical reaction in the formation of HbNO from hydroxyurea [115]. Scheme 7.16 depicts the proposed mechanisms of N O and HbNO formation during the reaction of deoxy and metHb with hydroxyurea. Oxidation of hydroxyurea by metHb produces deoxyHb and the nitroxide radical (25,... 

Radical trapping studies, 14 277 Radicidation, 8 655 Radioactive decay, 21 287—288 particles associated with, 21 291 Radioactive decay properties of uranium isotopes, 25 393 Radioactive emission, interaction with tracer molecules, 21 276 Radioactive iodine, protection from,... 

Motton el al. made a spin-trapping study of the radicals induced by a xenon arc lamp from promazine and chlorpromazine. The results suggested that the radical from photodechlorination of chlorpromazine was sufficiently more reactive than the promazine radical to amount for the order of magnitude difference in the potencies of their phototoxicities [233],... 

The esr parameters for a large number of alkyl aryl nitroxides have been collected recently, in part as a source of reference for spin trapping studies (Rockenbauer et al., 1978) the conformations of these nitroxides are also discussed. A selection of spectral parameters for spin adducts of the more important nitroso traps which have been discussed in this Section is presented in Table 2. 

It would probably not be unfair to suggest that in many early spin-trapping studies there was a tendency to turn an unscientifically blind eye to some of the... 

On the other hand, in l,l,l,3,3,3-hexafluoropropan-2-ol, a solvent with even stronger ability to solvate anions than water and therefore of great usefulness for spin trapping studies (see below), E° values will presumably be higher than in water. 

Since the primary photochemical process for nitrosoalkane involves the homolytic dissociation of the C—N bond to generate free radicals141, recent studies on the photochemistry of nitrosoalkanes pay more attention to radical reactions and to the methods of detection, such as spin trapping studies coupled with ESR techniques142. 

Buettner, G. R., KeUey, E. E., and Bums, C. P., 1993, Membrane hpid free radicals produced from LI 210 murine leukemia ceUs by photofrin photosensitization an electron paramagnetic resonance spin trapping study. Cancer Res. S3 3670-3673. 

Oubrahim, H., Richard, J.M., Cantin-Esnault, D. (1998). Peroxidase-mediated oxidation, a possible pathway for activation of the fungal nephrotoxin orellanine and related compounds. ESR and spin-trapping studies, Free Radic. Res., 28, 497-505. 

Evidence for seasonal fluctuations in the export of sinking POM from the euphotic zone has been obtained from sediment trap studies. As shown in Figure 23.3, seasonal variations in the flux of sinking biogenic hard and soft parts are detectable even in the deep zone. Furthermore, interannual variations in POC and PIC production lead to similar shifts in the deepwater fluxes of these particles. 

Field trapping studies indicated that -hexyl -hexanoate, E)-2-hexenyl -hexanoate, and -octyl w-butyrate were pheromone components of the rice leaf bug, Trigonotylus caelestialium, and mixtures in ratios of 1000 400 500 10—100 were attractive to males." ... 

Spectroscopic evidence for peroxy radical 51 was obtained from ESR. Spin trapping studies monitored by ESR have demonstrated that 02 reacts efficiently with 2-nitrobenzenesulfonyl chloride and results in the formation of the peroxy radical intermediate 51 (equation 88). The 5,5-dimethyl-l-pyrroline-l-oxide (DMPO) spin adduct of 51 shows the hyperfine coupling constants, aN = 1.8 G and aH = 10.1 G. 

Takeuchi and co-workers showed that the ratio of N- to C-substitution on the apparent intermediate 75a by a series of aromatics in arene/TFA mixtures was sensitive to the structure of the precursor to 75a (phenyl azide, N-phenylhydroxylamine or O-trifluoroacetyl-N-phenylhydroxylamine) even though the decomposition rates of these precursors were unaffected by the identity of the arene. This result is consistent with the characterization of 75a from N3 and Br trapping studies as a short-lived intermediate that will usually react through ion pair or preassociation processes that may be leaving-group dependent. ... 

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