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Relevant bibliographies by topics / Free radicals (Chemistry) – Analysis

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Academic literature on the topic 'Free radicals (Chemistry) – Analysis'

Author: Grafiati

Published: 4 June 2021

Last updated: 19 February 2022

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Journal articles on the topic "Free radicals (Chemistry) – Analysis"

1

Cherkasov, Artem R., M. Jonsson, Vladimir I. Galkin, and Rafael A. Cherkasov. "Correlation analysis in the chemistry of free radicals." Russian Chemical Reviews 70, no. 1 (January 31, 2001): 1–22. http://dx.doi.org/10.1070/rc2001v070n01abeh000574.

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Cherkasov, A. R., M. Jonsson, V. I. Galkin, and R. A. Cherkasov. "ChemInform Abstract: Correlation Analysis in the Chemistry of Free Radicals." ChemInform 32, no. 29 (May 25, 2010): no. http://dx.doi.org/10.1002/chin.200129286.

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Liu, Yuyan, Xiaoyong Liu, Hongping Liu, Yuanqing Guo, Guangming Huang, Jieli Lin, Hui Gao, and Chuanxi Duan. "Spectroscopic analysis of asymmetric top free radicals." Science in China Series B: Chemistry 44, no. 1 (February 2001): 7–16. http://dx.doi.org/10.1007/bf02879730.

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Simándi, László I. "Analysis of free radicals in biological systems." Reaction Kinetics & Catalysis Letters 59, no. 2 (November 1996): 383–84. http://dx.doi.org/10.1007/bf02068138.

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Das, Suresh, and Clemens von Sonntag. "The Oxidation of Trimethylamine by OH Radicals in Aqueous Solution, as Studied by Pulse Radiolysis, ESR, and Product Analysis. The Reactions of the Alkylamine Radical Cation, the Aminoalkyl Radical, and the Protonated Aminoalkyl Radical." Zeitschrift für Naturforschung B 41, no. 4 (April 1, 1986): 505–13. http://dx.doi.org/10.1515/znb-1986-0418.

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Hydroxyl radical reactions with trimethylamine in aqueous solution lead to the formation of the aminoalkyl radical (CH3)2NCH2 (A) and its conjugated acid (CH3)2HN+CH2 (AH+) as well as to the alkylamine radical cation (CH3)3N+(N+). These radicals are transform ed into each other by hydrolytic reactions, e.g.[xxx]Radicals AH+ are more acidic (pKa ≈ 3.6) than the radicals N+(pKa ≈ 8.0). Consequently, N+ predom inate over AH+ under quasi equilibrium conditions (e.g. in the presence of phosphate buffer) and are the only species observed by ESR in acid solutions. Reacting with the protonated amine. OH radicals abstract hydrogen at nitrogen and at carbon with comparable ease. Reaction of OH radicals with the free amine may initially also generate N+, beside H-abstraction at carbon. Radicals A’ absorb more strongly at 260 nm (ε = 3390 dm3mol-1cm-1) than the radical cation N+(ε = 950 dm3mol-1cm-1). Radical A' has reducing properties whereas radicals AH+ and N+ have oxidizing properties and hence can be monitored with p-nitroacetophenone (the reducing radicals), and Fe(CN)64- , N ,N'-tetramethyl-p-phenylenediamine and 2,2'-azinobis-(3-ethyl-benzthiazoline- 6-sulphonate) (the oxidizing radicals). These radicals mainly (≥ 85 % ) disproportionate. one of the products being formaldehyde

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SANO, HIROAKI. "Chemistry and biology of active oxygens and free radicals. 2. Analyses of active oxygens and free radicals." Kagaku To Seibutsu 37, no. 5 (1999): 328–33. http://dx.doi.org/10.1271/kagakutoseibutsu1962.37.328.

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Doi, Naoki, Yasushi Sasai, Yukinori Yamauchi, Tetsuo Adachi, Masayuki Kuzuya, and Shin-ichi Kondo. "Kinetic analysis of mechanoradical formation during the mechanolysis of dextran and glycogen." Beilstein Journal of Organic Chemistry 13 (June 19, 2017): 1174–83. http://dx.doi.org/10.3762/bjoc.13.116.

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A detailed electron spin resonance (ESR) analysis of mechanically induced free radicals (mechanoradicals) formation of glucose-based polysaccharides, dextran (Dx) and glycogen (Gly) was performed in comparison with amylose mechanoradicals. The ESR spectra of the samples mechanically fractured at room temperature were multicomponent. The radical concentration of Dx and Gly mechanoradicals gradually decreased during vibratory milling after reaching the maximum value. Although the molecular weight of Dx or the particle diameter of Gly steeply diminished until reaching the each maximum value of radical concentration, after that the molecular weight or the particle diameter slowly decreased. These results suggested that Dx and Gly mechanoradicals might be more unstable than amylose radicals possessing an intramolecular helical structure due to the branched structure.

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Akhter, Parveen, Uzma Ashiq, Rifat A. Jamal, Zara Shaikh, Mohammad Mahroof-Tahir, Mehreen Lateef, and Rooma Badar. "Chemistry, Alpha-glucosidase and Radical Scavenging Properties of Uranyl(VI) Hydrazide Complexes." Medicinal Chemistry 15, no. 8 (November 18, 2019): 923–36. http://dx.doi.org/10.2174/1573406415666190213101044.

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Background: Antioxidant, anti-inflammatory, antiviral and antitumoral activities among others are essential characteristics in the development of novel therapeutic compounds. Acid hydrazides can form complexation with certain metal ions that positively enhance these biological characteristics. Objective: Five new complexes of uranium with hydrazide ligands were synthesized at room temperature. Methods: Methods: The characterization was done by spectroscopic methods (ESI-Mass, IR, 1H-NMR, 13CNMR), CHN analysis and conductivity measurements. Metal complexes along with their respective ligands were further screened for their antioxidant (DPPH, superoxide and nitric oxide free radicals) properties and enzyme inhibition (α-glucosidase) activities. Results: Elemental and spectral data indicate octahedral geometry around uranyl (UO2 2+) species. Magnetic moments indicate the diamagnetic nature of uranyl(VI) ion in the complex in solid state. IC50 values showed potential antioxidant behavior of uranyl complexes demonstrating interesting structure-activity relationships. In general, hydrazide ligands were not active against superoxide and nitric oxide radicals while varying degree of results were observed against DPPH radical whereas all uranyl-complexes showed promising radical scavenging activities against all of them. Promising inhibitory potential was displayed by UO2 +2 hydrazide complexes against α- glucosidases whereas free hydrazide ligands were inactive. Conclusion: Structure function relationship demonstrates that the nature of ligand, position of substituent, electronic and steric effects are significant factors affecting the radical scavenging and enzyme inhibition activities of the compounds.

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Zhang, Yong-Kang, Dao-Hui Lu, and Guang-Zhi Xu. "Synthesis and Plane Selective Spin Trapping of a Novel Trap 5,5-Dimethyl-3-(2-ethoxycarbonylethyl)-1-pyrroline N-oxide." Zeitschrift für Naturforschung B 45, no. 7 (July 1, 1990): 1075–83. http://dx.doi.org/10.1515/znb-1990-0729.

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A novel cyclic nitrone spin trap 5,5-dimethyl-3-(2-ethoxycarbonylethyl)-1-pyrroline N-oxide has been prepared and its ability to trap a series of transient free radicals has been investigated. This nitrone scavenges free radicals to give persistent nitroxides, e.g., the half life-times of hydroxyl radical adducts and tert-butoxy radical adducts in benzene >30 min, and the life-time of acetyl adducts >60 min. The EPR spectrum of 2,2-dimethyl-4-(3-hydroxypropyl)pyrrolidinyl-1-oxyl aminoxyl shows that the hyperfine splitting constants of twoβ-hydrogens are equal to 14.58 G and 23.29 G respectively, i.e., the two β-hydrogens are not magnetically equivalent. Radical addition to the nitrone is probably plane selective affording only one of the two possible geometric isomer pairs of the spin adduct nitroxides. The trans approach mechanism is proposed through configuration and conformation analysis.

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Prior, Ronald L., and Guohua Cao. "Analysis of Botanicals and Dietary Supplements for Antioxidant Capacity: A Review." Journal of AOAC INTERNATIONAL 83, no. 4 (July 1, 2000): 950–56. http://dx.doi.org/10.1093/jaoac/83.4.950.

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Abstract Free radicals and other reactive species are considered to be important causative factors in the development of diseases of aging such as cancer and cardiovascular diseases. This relationship has led to considerable interest in assessing the antioxidant capacity of foods and botanicals and other nutritional antioxidant supplements. The use of the oxygen radical absorbance capacity (ORAC) assay as a tool for antioxidant assessment is described and proposed as a method for comparing botanical sources and for standardizing nutritional supplements. The free radical or oxidant source is important and direct comparisons cannot be made between procedures that use different sources. The ORAC procedure uses 2,2′-azobis(2-amidinopropane) dihydrochloride as a peroxyl radical source, which is relevant to biological systems because the peroxyl radical is the most abundant free radical. Other oxidant sources (hydroxyl radical and Cu++) can also be used to characterize antioxidants in botanicals. Phenolics or polyphenolics are responsible for most of the antioxidant capacity in fruits, vegetables, and most botanical antioxidant supplements. Although little is known about the absorption and metabolism of these components, improvement in the in vivo antioxidant status has been observed in human subjects following consumption of antioxidant botanicals. The ORAC method provides a basis from which to establish appropriate dietary intakes that might impact health outcomes.

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Dissertations / Theses on the topic "Free radicals (Chemistry) – Analysis"

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Chiu, Yuen-Yuen. "Experimental and theoretical analysis of free radical crosslinking polymerizations /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu148785841798507.

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Bucknall, Martin Paul Medical Sciences Faculty of Medicine UNSW. "Dityrosine as a biomarker of free radical induced oxidative damage in diseases of ageing." Awarded by:University of New South Wales. School of Medical Sciences, 2006. http://handle.unsw.edu.au/1959.4/30207.

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o,o???-Dityrosine (dityrosine), an oxidation product of tyrosine produced by reaction between tyrosyl radicals, is becoming established as a biomarker of free radical oxidative protein damage in vivo. Attempts to measure dityrosine concentrations in various physiological and pathological systems have produced varied and often contradictory results. Dityrosine concentrations in urine, plasma, cerebrospinal fluid (CSF) and brain tissue varying over three orders of magnitude have been reported, together with inconsistent claims of significant dityrosine elevation in several ageing-related pathologies. Some of these findings have contributed to the implication of free radical activity in the pathology of several neurodegenerative disorders, vascular and ocular abnormalities and in phagocyte response to infection. The aim of this study was to test the hypothesis that dityrosine levels are elevated in ageing and ageing-related disease. The study also aims to determine the utility of dityrosine measurement as an index of oxidative damage, and elucidate possible explanations for the inconsistent levels reported. An assay for the quantification of dityrosine was developed using capillary HPLC with electrospray tandem quadrupole mass spectrometry (HPLC-MS/MS). The assay was highly specific for dityrosine and has the highest absolute sensitivity for dityrosine of any method reported to date, with a detection limit of 3 femtomoles of dityrosine on-column. Urine samples from volunteers of different age and from hospital patients with various pathologies were analysed. Plasma protein hydrolysates from control, Alzheimer???s and stroke subjects were analysed, together with hydrolysates of post mortem brain tissue from Alzheimer???s and control subjects. Urinary dityrosine level is elevated in states of acute infection and inflammation, but does not correlate with age or chronic disease. Protein dityrosine in four sections of Alzheimer???s brain was not significantly different from control sections. Dityrosine was present in human plasma and tissue proteins at approximately 5-35 residues per million tyrosine residues, and in normal urine at 5-25 micromol/mol creatinine or 20-200 nM. Most of the discrepancies in the literature relate to inadequate specificity of the analytical method. Interpretation of published data with critical appraisal of measurement technology specificity is essential in developing an accurate understanding of the role of free radicals in ageing and disease.

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Ren, Jiyun. "Analysis of free radical characteristics in biological systems based on EPR spectroscopy, employing blind source separation techniques." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36797479.

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Ren, Jiyun, and 任紀韞. "Analysis of free radical characteristics in biological systems based on EPR spectroscopy, employing blind source separation techniques." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36797479.

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Hsu, Chih-Pin George. "An integrated analysis of styrene/unsaturated polyester free radical cross-linking polymerizations /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487780393264696.

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Liu, Chia-chi. "Oxidation of ascorbate by protein radicals in simple systems and in cells." Phd thesis, Australia : Macquarie University, 2007. http://hdl.handle.net/1959.14/16746.

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Thesis (PhD) -- Macquarie University, Division of Environmental and Life Sciences, Dept. of Chemistry and Biomolecular Sciences, 2007.
Bibliography: leaves 295-322.
Generation of peroxide groups in proteins exposed to a wide variety of reactive oxygen species (ROS) requires an initial formation of protein carbon-centred or peroxyl free radicals, which can be reduced to hydroperoxides. Both protein radicals and protein hydroperoxides are capable of oxidizing important biomolecules and thus initiate biological damage. In this study, we investigated the inhibition of protein hydroperoxide formation by ascorbate and GSH in gamma-irradiated HL-60 cells.--We used HL-60 cells as a model for general protection of living organisms by ascorbate (Asc) and glutathione (GSH) from the deleterious effects of protein hydroperoxides generated by radicals produced by gamma radiation. Measurement by HPLC indicated that incubation of HL-60 cells with Asc in the presence of ascorbate oxidase resulted in the accumulation of intracellular Asc. The intracellular Asc levels were lowered by irradiation, demonstrating intracellular consumption of Asc by the radiation-generated radicals. Exposure of HL-60 cells to increasing gamma irradiation doses resulted in increasing accumulation of protein peroxides in the cells. This was measured by the FOX assay. A significant decrease in intracellular protein hydroperoxides was noted when the cells were treated with ascorbic acid before irradiation. A dose-dependent protective effect of Asc was observed. Asc loading also provided strong protection from radiation-generated protein hydroperoxides independently of the composition of the external medium, showing that only the radicals formed within the cells were effective in oxidizing the cell proteins. Similarly, protein peroxidation was inhibited in cells with enhanced levels of GSH and increased when the intracellular GSH concentration was reduced. These findings indicate that ascorbate and GSH are important antioxidants in protecting cells from oxidative stress associated with the generation of protein hydroperoxide.
Mode of access: World Wide Web.
xxix, 322 leaves ill

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Mills, Tim. "Studies in free radical chemistry." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342465.

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梁韻詩 and Wan-sze Leung. "High resolution spectroscopy of free radicals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31237319.

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Leung, Wan-sze. "High resolution spectroscopy of free radicals /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19737610.

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Crockett, Rowena. "Generation of free radicals from heterocyclic compounds." Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290239.

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Tetrazolinones, thiatriazole 1-oxides and meso-ionic oxatriazoles were investigated as sources of free radicals. Mono-substituted tetrazolinones decomposed at their melting points. Nitrosation and nitration of the tetrazolinone ring was unsuccessful, although alkoxyalkylation of the ring took place in ether in the presence of nitrosomium and nitronium tetrafluoroborate. The tetrazolinone ring was photolytically unstable, and both eliminated nitrogen and cycloreverted. γ-irradiation of the naphthyl deivative caused cleavage of the nitrogen-hydrogen bond to give a radical which was identified by spin trapping and esr spectroscopy. Thiatriazolyl radicals were generated from thiatriazol-1-ium salts by reduction over sodium metal. Deuterium and nitrogen-15 labelled diphenylthiatriazolium salts were prepared in the reaction between thiatriazole 1-oxides and phosphorus pentachloride or pentabromide. This allowed an unambiguous assignment of the nitrogen and hydrogen hyperfine coupling constants in the esr spectrum of the unlabelled thiatriazolyl radical. X-ray crystallographic analysis was carried out on single crystals of 2,4-diphenyl-2,5-dihydro-1,2,3,5-thiatriazol 1-oxide and 2,4-diphenyl-2H-1,2,3,5-thiatriazol-1-ium bromide. Meso-ionic oxatriazolones were relatively stable to thermolysis, whereas oxatriazolimines decomposed at their melting points. The oxatriazolones decomposed on photolysis via two mechanistic pathways, while the oxatriazol-imines were resistant to photolysis. Radicals were generated by γ-irradiation and oxidation via decomposition of the heterocyclic ring. Electrochemical reduction of nitrophenyl derivatives allowed an investigation of radicals in which the heterocyclic ring was remote from the radical centre. Photochemical reaction between the nitrophenyl derivatives of the oxatriazole and tetrahydrofuran produced oxy-nitroxide radicals which were realatively long-lived and in which the heterocyclic ring was intact. The rates of hydrolysis and crystal structures of three diacetylazolinones, including diacetyltetrazolinone were investigated with the aim of determining whether a correlation existed between bond lengths and reactivity. The relative rates of hydrolysis were found to be independent of the bond lengths. However a correlation was found between the rates of hydrolysis and the acidity of the unsubstituted azolinones.

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Books on the topic "Free radicals (Chemistry) – Analysis"

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Free radicals: Biology and detection by spin trapping. New York: Oxford University Press, 1999.

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Lund, A. EPR of Free Radicals in Solids II: Trends in Methods and Applications. Dordrecht: Springer Netherlands, 2012.

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3

Herzberg, Gerhard. The spectra and structures of simple free radicals: An introduction to molecular spectroscopy. Mineola, N.Y: Dover Publications, 2003.

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Herzberg, Gerhard. The spectra and structures of simple free radicals: An introduction to molecular spectroscopy. New York: Dover Publications, 1988.

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Free radicals in organic chemistry. Chichester: Wiley, 1995.

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Leffler, John E. An introduction to free radicals. New York: Wiley, 1993.

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Favier, A. E., J. Cadet, B. Kalyanaraman, M. Fontecave, and J. L. Pierre, eds. Analysis of Free Radicals in Biological Systems. Basel: Birkhäuser Basel, 1995. http://dx.doi.org/10.1007/978-3-0348-9074-8.

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Walling, Cheves. Fifty years of free radicals. Washington, DC: American Chemical Society, 1995.

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Free radicals and antioxidant protocols. 2nd ed. New York: Humana Press, 2010.

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H, Solomon D., ed. The chemistry of free radical polymerization. Oxford, OX, U.K: Pergamon, 1995.

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Book chapters on the topic "Free radicals (Chemistry) – Analysis"

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Garrel, C., and M. Fontecave. "Nitric oxide: Chemistry and biology." In Analysis of Free Radicals in Biological Systems, 21–35. Basel: Birkhäuser Basel, 1995. http://dx.doi.org/10.1007/978-3-0348-9074-8_3.

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Pierre, J. L. "Chemistry of dioxygen and its activated species." In Analysis of Free Radicals in Biological Systems, 1–10. Basel: Birkhäuser Basel, 1995. http://dx.doi.org/10.1007/978-3-0348-9074-8_1.

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Armstrong, Donald, and Richard Browne. "The Analysis of Free Radicals, Lipid Peroxides, Antioxidant Enzymes and Compounds Related to Oxidative Stress as Applied to the Clinical Chemistry Laboratory." In Free Radicals in Diagnostic Medicine, 43–58. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-1833-4_4.

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Dolbier, William R. "Fluorinated free radicals." In Organofluorine Chemistry, 97–163. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/bfb0119266.

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Lappert, M. F. "Aspects of Organometallic Free Radical Chemistry." In Organic Free Radicals, 101–2. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73963-7_50.

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Scaiano, J. C. "Two Photon Processes in Free Radical Chemistry." In Organic Free Radicals, 183–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73963-7_91.

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de Montellano, Paul R. Ortiz. "Free Radicals in the Catalytic Chemistry of Hemoproteins." In Organic Free Radicals, 151. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73963-7_75.

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Baumann, U., and M. Schmittel. "Solution Chemistry of Keto and Enol Cation Radicals." In Organic Free Radicals, 189. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73963-7_94.

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Mattay, J. "Radical Ions and Photochemical Charge Transfer Phenomena in Organic Chemistry." In Organic Free Radicals, 119–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73963-7_59.

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Joseph, Jomy, and Andrey P. Antonchick. "Free Radicals in Heterocycle Functionalization." In Topics in Heterocyclic Chemistry, 93–149. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/7081_2017_8.

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Conference papers on the topic "Free radicals (Chemistry) – Analysis"

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Kennedy, C. E., K. Terwilliger, and G. J. Jorgensen. "Furthur Analysis of Accelerated Exposure Testing of Thin-Glass Mirror Matrix." In ASME 2007 Energy Sustainability Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/es2007-36182.

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Concentrating solar power (CSP) companies have deployed thin-glass mirrors produced by wet-silver processes on ∼1-mm-thick, relatively lightweight glass. These mirrors are bonded to metal substrates in commercial installations and have the confidence of the CSP industry. Initial hemispherical reflectance is ∼93%–96%, and the cost is ∼$16.1/m2–$43.0/m2. However, corrosion was observed in mirror elements of operational solar systems deployed outdoors for 2 years. National Renewable Energy Laboratory (NREL) Advanced Materials Team has been investigating this problem. First, it was noted that this corrosion is very similar to the corrosion bands and spots observed on small (45 mm × 67 mm) thin-glass mirrors laminated to metal substrates with several different types of adhesives and subjected to accelerated exposure testing (AET) at NREL. The corrosion appears as dark splotches in the center of the mirror, with a corresponding 5%–20% loss in reflectivity. Secondly, two significant changes in mirror manufacture have occurred in the wet-chemistry process because of environmental concerns. The first is the method of forming a copper-free reflective mirror, and the second is the use of lead-free paints. However, the copper-free process requires stringent quality control and the lead-free paints were developed for interior applications. A test matrix of 84 combinations of sample constructions (mirror type/back-protective paint/adhesive/substrate) was devised for AET as a designed experiment to identify the most-promising mirrors, paints, and adhesives for use with concentrator designs. Two types of accelerated exposure were used: an Atlas Ci5000 WeatherOmeter (CI5000) and a BlueM damp-heat chamber. Based on an analysis of variance (ANOVA), the various factors and interactions were modeled. These samples now have more than 36 months of accelerated exposure, and most samples have completed their test cycle. We will discuss the results of the final exposure testing of these mirror samples. Glass mirrors with copper back-layers and heavily leaded paints have been considered robust for outdoor use. However, the basic mirror composition of the new mirrors is radically different from that of historically durable solar mirrors, and the outdoor durability must be determined.

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Gámez-Montaño, Rocío, Pedro A. Cano, and Alejandro Islas-Jácome. "Synthesis of spiro-cyclohexendienone-gamma-lactams via free-radicals and study of thermal regioselective spirocyclization." In The 21st International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2017. http://dx.doi.org/10.3390/ecsoc-21-04779.

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Mulyani, Hani, Yati Maryati, Euis Filailla, Agustine Susilowati, Puspa D. N. Lotulung, and Aspiyanto Aspiyanto. "Benefits of fermented beet (Beta vulgaris L.) against digestive infection Escherichia coli and free radicals prevention." In PROCEEDINGS OF THE 5TH INTERNATIONAL SYMPOSIUM ON APPLIED CHEMISTRY 2019. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5134589.

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Wu, Hanqing. "Organic and Drug Molecules Spin Traps and Free Radicals Multi-frequency EPR Spectra Simulation by Fast Fourier Transform (FFT)." In The 1st International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 1997. http://dx.doi.org/10.3390/ecsoc-1-02058.

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Lee, Yoon Sin, and Mi Ryeong Song. "Analysis of Correlation between Sleep, Fatigue, and Free Radicals in Women." In Healthcare and Nursing 2015. Science & Engineering Research Support soCiety, 2015. http://dx.doi.org/10.14257/astl.2015.104.17.

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Wang, S. M., G. X. Zhang, Q. Zhang, and X. X. Wang. "The optical spectra analysis of free oxygenic radicals in atmospheric microwave plasmas." In 2009 IEEE 36th International Conference on Plasma Science (ICOPS). IEEE, 2009. http://dx.doi.org/10.1109/plasma.2009.5227540.

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Pfaendtner, Jim, Linda J. Broadbelt, and Q. Jane Wang. "Quantum Chemical Studies of Free-Radical, Hindered Phenol Stabilizers." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-64007.

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Quantum chemical investigations of the action of hindered phenol radical stabilizers in lubricant degradation chemistry have been completed. We are currently developing the first mechanistic models of lubricant degradation with the aim of including the chemistry of additives such as radical stabilizers that are found in commercial lubricant formulations. A key component of development of these models is obtaining reliable estimates of the kinetic parameters for all reactions. Specifically, rate constants and structure-reactivity correlations for the interaction of hindered phenol radical stabilizers with small peroxy radicals have been sought using quantum chemistry and transition state theory. Accurate thermodynamic properties of hindered phenol radical stabilizers and structure-reactivity relationships have been obtained. Such relationships provide researchers the ability to quickly estimate reactivity of hindered phenol stabilizers using their thermodynamic properties and therefore may be useful in additive design.

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Li, Y. S., Z. M. Yue, F. R. Liu, J. S. Qi, and J. Gao. "The Design and Analysis of Free Bending Tube Bending Machine." In The International Workshop on Materials, Chemistry and Engineering. SCITEPRESS - Science and Technology Publications, 2018. http://dx.doi.org/10.5220/0007435301150121.

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Patil, Swanand, Anjum Mehta, Hyoungseok Bang, Hyoung J. Cho, and Sudipta Seal. "A Novel Nanomaterial Based Electrochemical Sensor for Free Radical Detection." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-82094.

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Hydrogen peroxide (H2O2) is not only a product of the reactions catalyzed by a large number of highly selective oxidases but also an essential mediator in food, pharmaceutical and environmental analysis. Therefore its determination is of paramount importance in many areas in chemical, biological and clinical fields. Most H2O2 biosensors developed till date are based on enzymes and proteins which have a limited sensor life. Moreover, complex procedures are followed for sensor fabrication. Therefore an inorganic material based sensor with a simple design and longer shelf-life is highly desirable. In this work, the development of a novel cerium oxide nanomaterial based electrochemical sensor for the measurement of hydrogen peroxide is described. This has direct ramifications in the development of sensors for other superoxide radicals.

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Wylde, Jonathan J. "The Challenges Associated with Reaction Products Left in Scale Inhibitor Species after Radical Polymerization." In SPE International Oilfield Scale Conference and Exhibition. SPE, 2014. http://dx.doi.org/10.2118/spe-169778-ms.

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Abstract The use of polymeric scale inhibitors has been ubiquitously accepted by the oil and gas industry for many years. There are many benefits to the use of this type of chemistry that include aspects such as high performance, scale species selectivity, enhanced brine compatibility, favorable environmental properties and high thermal stability. A very common way to manufacture polymeric scale inhibitors is via free radical polymerization. Here an initiator is used to propagate the generation of free radicals from a species, such as hydrogen peroxide. The initiator chemistry can be very varied and usually comprises different types of transition metal salts, hypophosphite or persulfate species. Different monomer units can be polymerized using different initiator and free radical species to yield the same polymer. However, subtle differences can result, including poly-dispersity, average molecular weight and different residual composition. The implications for the end user of the chemistry can be profound regarding performance differences in aspects such as detectability, compatibility, thermal stability and sometimes even scale inhibition and adsorption efficacy. A case study has been presented where a very commonly used sulfonated copolymer species from four different sources was evaluated in a whole host of compatibility and performance tests. The different routes used different combinations of hydrogen peroxide and transition metal initiator or persulfate/hypophosphite combinations as the free radical source. There were major differences seen in the compatibility of these products with different scale inhibitors and then in performance. The tests performed highlighted the differences that can occur between the different radical polymerization synthetic routes mentioned above. The conclusions show that there are many benefits to being able to control the manufacturing process of scale inhibitor species in order to ensure the full composition is understood and can be quantified. The benefits to owning the supply chain are highlighted and lead to not only better control of quality and cost but, more importantly, to the overall risk reduction for the end user in the end use application.

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