Relevant bibliographies by topics / Base radical

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  2. Dissertations / Theses
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  5. Conference papers
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Academic literature on the topic 'Base radical'

Author: Grafiati
Published: 4 June 2021
Last updated: 19 February 2022

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Journal articles on the topic "Base radical"

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Roché, Michel. "Base, thème, radical." Recherches linguistiques de Vincennes, no. 39 (December 1, 2010): 95–134. http://dx.doi.org/10.4000/rlv.1850.

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Hildenbrand, Knut. "The SO4·̄induced Oxidation of 2′-Deoxyuridine-5′-phosphate, Uridine-5′-phosphate and Thymidine-5′-phosphate. An ESR Study in Aqueous Solution." Zeitschrift für Naturforschung C 45, no. 1-2 (February 1, 1990): 47–58. http://dx.doi.org/10.1515/znc-1990-1-210.

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Abstract Reactions of photolytically generated SO4·̄ with 2′-deoxyuridine-5′-phosphate (5′-dUMP), uridine-5′-phosphate (5′-UMP) and thymidine-5′-phosphate (5′-dTMP) were studied by ESR spectroscopy in aqueous solution under anoxic conditions. From 5′-dUMP and 5′-UMP the 5′,5-cyclicphosphate-6-yl radicals 10 and 11 were generated (pH 2 -11) whereas from 5′-dTMP at pH 3 -8 the 5,6-dihydro-6-hydroxy-5-yl radical 14 and at pH 7 -1 1 the 5-methylene-2′-deoxyuridine-5′-phosphate radical 15 was produced. In the experiments with 5′-UMP in addition to radical 11 the signals of sugar radicals 12 and 13 were detected. It is assumed that the base radical cations act as intermediates in the SO4·̄-induced radical reac­tions. The 5′-phosphate group adds intramolecularly to the C(5)−C(6) bond of the uraclilyl radical cation whereas the thymidyl radical cation of 5′-dTMP reacts with H2O at pH < 8 to yield the 6-OH-5yl adduct 14 deprotonates at pH > 7 thus forming the allyl-type radical 15. In 5′-UMP transfer of the radical site from the base to the sugar moiety competes with intramolecular phosphate addition.
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Macernis, Mindaugas. "On the Dimers Stability of Allicin and Its Derivatives Interacting with AT, GC, and DNA Bridge: DFT Study." Journal of Chemistry 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/1428508.

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Allicin and its derivatives are physiologically active molecules with many potential health benefits. It is not clear if they have a direct effect on DNA or protein. In order to elucidate the allicin and its derivatives’ effect on DNA base pairs, we investigated various complexes of base pair and its bridge with an allicin and its derivatives. The investigated allicin derivatives were (E)-Ajoene, (Z)-Ajoene, Amz121, and Bmz73 radicals. The DFT calculation results revealed that the investigated molecules would favor binding to bridge of the base pairs instead of directly affecting the base pairs. The Bmz73 radical could break DNA by change bonding in it because the Bmz73 radical significantly affected the P-O bond of the bridge of base pair.
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YILMAZ, Zehra Kübra, Belma ASIM, and Ozlem OZDEMIR. "In vitro antioxidant properties of 2-(4-(2-hydroxybenzylideneamino)benzylideneamino)benzoic acid." ICONTECH INTERNATIONAL JOURNAL 5, no. 3 (September 25, 2021): 7–12. http://dx.doi.org/10.46291/icontechvol5iss3pp7-12.

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In recent years, it has attracted great attention to determine and appraise synthetic antioxidants with high free radical scavenging capacity associated with various disorders. Because synthetic antioxidants are widely used in place of native antioxidants as they are influential and less expensive. In this study, the antioxidant activity of the newly synthesized asymmetric diimine Schiff base was determined by using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, ferrous ion chelation (FIC) activity and total antioxidant activity (Phosphomolybdenum assay) methods. The effective concentration (IC50) values were calculated for the Schiff base and standards. According to the results of DPPH radical scavenging, ferrous ion chelation and total antioxidant methods, Schiff base showed a well antioxidant activity. It was determined that Schiff base is reactive towards DPPH radicals (IC50, 180.0 μM) and especially Fe+2 ions (IC50, 76.3 μM). It was also found that it actively reduces the Mo(VI) ion to the Mo(V) form (IC50, 121.5 μM). The our results indicate Schiff base, may be a fine candidate as a source of synthetic antioxidants and possibly strong drug.
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Wang, Pengfei, Yuli Li, and Guangwei Wang. "Tetrahydroxydiboron-Initiated Atom-Transfer Radical Cyclization." Synthesis 53, no. 19 (April 19, 2021): 3555–63. http://dx.doi.org/10.1055/a-1485-4956.

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AbstractIn this work, the first diboron reagent initiated atom-transfer radical cyclization was reported, in which the boryl radicals were generated by the homolytic cleavage of a B–B single bond weakened by the coordination of Lewis base. To clarify the role of carbonate and DMF in the cleavage of B–B bond, we calculated the free energy diagram of two pathways by density functional theory (DFT) investigations. The DFT calculation showed that the presence of carbonate facilitates the B–B bond cleavage to form boron radicals, which can be further stabilized by DMF. Subsequent atom-transfer cyclization initiated by stabilized dihydroxyboron radical is also energetically favored.
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Lim, Y. B., Y. Tan, M. J. Perri, S. P. Seitzinger, and B. J. Turpin. "Aqueous chemistry and its role in secondary organic aerosol (SOA) formation." Atmospheric Chemistry and Physics Discussions 10, no. 6 (June 9, 2010): 14161–207. http://dx.doi.org/10.5194/acpd-10-14161-2010.

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Abstract. There is a growing understanding that secondary organic aerosol (SOA) can form through reactions in atmospheric waters (i.e., clouds, fogs, and aerosol water). In clouds and wet aerosols, water-soluble organic products of gas-phase photochemistry dissolve into the aqueous phase where they can react further (e.g. with OH radicals) to form low volatility products that are largely retained in the particle phase. Organic acids, oligomers and other products form via radical- and non-radical reactions, including hemiacetal formation during droplet evaporation, acid/base catalyzation, and reaction of organics with other constituents (e.g. NH4+). This paper uses kinetic modeling, experiments conducted with aqueous carbonyl solutions in the presence and absence of OH radicals, electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry, and the literature to describe aqueous chemistry at cloud- and aerosol-relevant concentrations and during droplet evaporation. At least for aqueous reactions of glyoxal with OH radicals, chemical modeling can reproduce experiments conducted at cloud-relevant concentrations without including radical–radical reactions, whereas radical–radical reactions become dramatically more important at higher concentrations. We demonstrate that reactions with OH radicals tend to be faster and form more SOA than "non-radical" reactions (e.g., acid catalyzation).
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Schepp, N. P., and Y. Rodríguez-Evora. "Generation and reactivity of the radical cations of coniferyl alcohol and isoeugenol in solution." Canadian Journal of Chemistry 81, no. 6 (June 1, 2003): 799–806. http://dx.doi.org/10.1139/v03-075.

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Nanosecond laser flash photolysis of coniferyl alcohol and isoeugenol in acetonitrile leads to the formation of transient species that are identified as the corresponding radical cations. These radical cations decay with rate constants of ca. 1 × 106 s–1 in dry acetonitrile. Both radical cations react rapidly with hydroxylic solvents like water and alcohols to give 4-vinylphenoxyl radicals, indicating that these reagents behave as bases rather than nucleophiles. In addition, anionic reagents (acetate, cyanide, and chloride) react rapidly with the radical cations with second-order rate constants that are close to diffusion controlled. The main products generated in the presence of the anionic reagents are again the 4-vinylphenoxyl radicals, suggesting that these reagents also behave as bases. The lifetime of the radical cations in acidic acetonitrile was found to increase dramatically due to a shift in the radical cation – vinyl phenoxyl radical acid–base equilibrium to the side of the radical cation. An estimate of the pKa of the radical cation in acetonitrile of 4.0 was obtained from the data.Key words: radical cations, laser flash photolysis, lignan, vinylphenols.
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Zarei, Mohammad, Abdolvahab Seif, Khaled Azizi, Mohanna Zarei, and Jamil Bahrami. "Effect of phenolic radicals on the geometry and electronic structure of DNA base pairs: computational study." International Journal of Modern Physics C 27, no. 10 (August 29, 2016): 1650119. http://dx.doi.org/10.1142/s0129183116501199.

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In this paper, we show the reaction of a hydroxyl, phenyl and phenoxy radicals with DNA base pairs by the density functional theory (DFT) calculations. The influence of solvation on the mechanism is also presented by the same DFT calculations under the continuum solvation model. The results showed that hydroxyl, phenyl and phenoxy radicals increase the length of the nearest hydrogen bond of adjacent DNA base pair which is accompanied by decrease in the length of furthest hydrogen bond of DNA base pair. Also, hydroxyl, phenyl and phenoxy radicals influenced the dihedral angle between DNA base pairs. According to the results, hydrogen bond lengths between AT and GC base pairs in water solvent are longer than vacuum. All of presented radicals influenced the structure and geometry of AT and GC base pairs, but phenoxy radical showed more influence on geometry and electronic properties of DNA base pairs compared with the phenyl and hydroxyl radicals.
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Flitter, W. D., and R. P. Mason. "The spin trapping of pyrimidine nucleotide free radicals in a Fenton system." Biochemical Journal 261, no. 3 (August 1, 1989): 831–39. http://dx.doi.org/10.1042/bj2610831.

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The reaction of the hydroxyl radical, generated by a Fenton system, with pyrimidine deoxyribonucleotides was investigated by using the e.s.r. technique of spin trapping. The spin trap t-nitrosobutane was employed to trap secondary radicals formed by the reaction of the hydroxyl radical with these nucleotides. The results presented here show that hydroxyl-radical attack on thymidine, 2-deoxycytidine 5-monophosphate and 2-deoxyuridine 5-monophosphate produced nucleotide-derived free radicals. The results indicate that .OH radical attack occurs predominantly at the carbon-carbon double bond of the pyrimidine base. The e.s.r. studies showed a good correlation with previous results obtained by authors who used x- or gamma-ray irradiation to generate the hydroxyl radical. A thiobarbituric acid assay was also used to monitor the damage produced to the nucleotides by the Fenton system. These results showed qualitative agreement with the spin-trapping studies.
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Ying, Wei-Wei, Wen-Ming Zhu, Hongze Liang, and Wen-Ting Wei. "Synthesis of Indoline-2,3-diones by Radical Coupling of Indolin-2-ones with tert-Butyl Hydroperoxide." Synlett 29, no. 02 (September 14, 2017): 215–18. http://dx.doi.org/10.1055/s-0036-1589106.

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A novel strategy has been developed for the synthesis of indoline-2,3-diones through a metal-free radical-coupling reaction. Alkyl radicals derived from indolin-2-ones through a radical-transfer reaction combine with the tert-butylhydroperoxy radical readily generated from commercially available tert-butyl hydroperoxide to afford 3-(tert-­butylperoxy)indolin-2-one intermediates that can be further transformed into indoline-2,3-diones under air. This strategy provides a ­simple and efficient route to the construction of a C=O bond without the use of any metal catalyst or base.
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Dissertations / Theses on the topic "Base radical"

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Chin, Melanie Soo, and m. chin@cqu edu au. "Towards a Reinterpretation of the Radical Theory of Associative Rings Using Base Radical and Base Semisimple Class Constructions." Central Queensland University. Computer Science, 2004. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20050411.102928.

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This research aims to refresh and reinterpret the radical theory of associative rings using the base radical and base semisimple class constructions. It also endeavours to generalise some results about ideals of rings in terms of accessible subrings. A characterisation of accessible subrings is included. By applying the base radical and base semisimple class constructions to many of the known results in established radical theory a number of gaps are uncovered and closed, with the goal of making the theory more accessible to advanced undergraduate and graduate students and mathematicians in related fields, and to open up new areas of investigation. After a literature review and brief reminder of algebra rudiments, the useful properties of accessible subrings and the U and S operators independent from radical class connections are described. The section on accessible subrings illustrates that replacing ideals with accessible subrings is indeed possible for a number of results and demonstrates its usefulness. The traditional radical and semisimple class definitions are included and it is shown that the base radical and base semisimple class constructions are equivalent. Diagrams illustrating the constructions support the definitions. From then on, all radical and semisimple classes mentioned are understood to have the base radical and base semisimple class form. Subject to the constraints of this work, many known results of traditional radical theory are reinterpreted with new proofs, illustrating the potential to simplify the understanding of radical theory using the base radical and base semisimple class constructions. Along with reinterpreting known results, new results emerge giving further insight to radical theory and its intricacies. Accessible subrings and the U and S operators are integrated into the development. The duality between the base radical and base semisimple class constructions is demonstrated in earnest. With a measure of the theory presented, the new constructions are applied to examples and concrete radicals. Context is supported by establishing the relationship between some well-known rings and the radical and related classes of interest. The title of the thesis, Towards a Reinterpretation of the Radical Theory of Associative Rings Using Base Radical and Base Semisimple Class Constructions, reflects the understanding that reinterpreting the entirety of radical theory is beyond the scope of this work. The conclusion includes an outlook listing further research that time did not allow.
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Rahim, Medhat H., Radcliffe Siddo, and Moushira Issa. "Tangram-base Problem Solving in Radical Constructivist Paradigm: High School Student-Teachers Conjectures." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-83015.

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Sanii, Laurie Shireen. "The effect of terminal base identity on radical cation injection into the DNA duplex." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/29377.

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Polenz, Ingmar, Andreas Laue, Tamas Uhrin, Tobias Rueffer, Heinrich Lang, Friedrich Schmidt, and Stefan Spange. "Thermally cleavable Imine Base / Isocyanate Adducts and Oligomers suitable as Initiators for Radical Homo- and Copolymerization." Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-152196.

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The addition of isocyanates to C=N double bonds of imines gives triazindione heterocycle structures; their thermal properties are reported. Mono-isocyanates were used to form 2:1 adducts with the imine bases 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) and 2-tert-butyl-1,1,3,3-tetramethylguanidine (tBuTMG). A 2:1 stoichiometry of the adducts was proven by NMR and IR spectroscopy, and single crystal X-Ray diffraction; certain cleavage temperatures (70 and 160 °C) were measured. Thermal analysis (TG-MS) of adducts indicates the release of free isocyanate during adduct cleavage. Furthermore, a new class of step-growth oligomers (MN = 750–7,000 g∙mol–1) composed of multi-functional isocyanates and these imine bases was introduced. Their systematic spectroscopic and thermal analysis is shown revealing the similarity in their chemical properties to the 2:1 adducts. Radical homo- and copolymerization of acrylates is initiated by the meta-stable adducts and oligomers of this work; the generation of novel telomeric block-copolymer architectures composed of polyacrylate and oligourea building blocks is demonstrated
Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
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Cassas, Fernando Albregard. "O acompanhamento terapêutico como prática do analista do comportamento: uma caracterização histórica com base no behaviorismo radical." Pontifícia Universidade Católica de São Paulo, 2013. https://tede2.pucsp.br/handle/handle/16716.

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Made available in DSpace on 2016-04-29T13:17:50Z (GMT). No. of bitstreams: 1 Fernando Albregard Cassas.pdf: 984002 bytes, checksum: 787a62ba52704b0b87c54e523fbb452a (MD5) Previous issue date: 2013-07-05
The work presented here is motivated by a clinical intervention that began to be practiced by behavior analysts in Brazil in the early 1990s. This form prioritizes the work in the natural environment and, therefore, more likely to act directly on controlling contingencies of client behavior. This type of control seems to have established in the literature, a polarization between Therapeutic Accompaniment (TA) and the clinical based on the greater or lesser ability to control to be undertaken on the client behavior. The research presented here aims to resume and analyze the therapeutic practices of radical behaviorist base in order to establish a comparison between them and the TA, thus define whether it is possible to assert the existence of this polarization. Four sets of papers were analyzed: bases of behavior therapy: publications Skinner and Ferster about therapy, the Behavior Modification; literature on the following therapeutic approaches: Functional Analytic Therapy, Acceptance and Commitment Therapy, Behavioral Activation, the literature on the brasilian therapeutic proposals: Analytical Behavioral Therapy, Therapy of Contingencies of Reinforcement, Pragmatic Behavioral Psychotherapy and Molar and Self Therapy, beyond literature about the TA. To compose this analysis, four analytical categories were developed: core concepts for the diagnosis, intervention strategies, effectiveness and generality. The analysis of the studies cited showed that the polarization in the terms formulated above, is not true because all proposed schedule forms to ensure the generalizability of the results. Could be defined, however, the existence of a "minimum repertoire client". This concerns the modeling repertoire of verbal behavior that will allow the client to modify alone, the environment itself. And that is the reason for this study in a natural environment where the client does not have the repertoire to modify their own environment independently, the therapist operates the changing client environment in order to build a better learning condition for that client. From this, suggestions for future research are made at the end of the work
A tese aqui apresentada é motivada por um trabalho de intervenção clínica que começou a ser praticado por analistas do comportamento brasileiros no início da década de 1990. Essa forma prioriza o trabalho em ambiente natural e, com isso, maior chance de atuar diretamente nas contingências controladoras do comportamento do cliente. Esse tipo de controle parece ter estabelecido, na literatura da área, uma polarização entre o Acompanhamento Terapêutico (AT) e o consultório com base na maior ou menor possibilidade de controle a ser assumido sobre o comportamento do cliente. A pesquisa aqui apresentada se propõe a resgatar e analisar as práticas terapêuticas de base behaviorista radical com vistas a estabelecer uma comparação entre elas e o AT para, assim, definir se é possível afirmar a existência dessa polarização. Para isso, quatro conjuntos de trabalhos foram analisados: bases da terapia comportamental: publicações de Skinner e de Ferster respeito da terapia, e sobre a Modificação de Comportamento; a literatura sobre as seguintes propostas terapêuticas: Functional Analytic Therapy, Acceptance and Commitment Therapy, Behavioral Activation; a literatura sobre as propostas terapêuticas nacionais: Terapia Analítico‐ comportamental, Terapia por Contingências de Reforçamento, Psicoterapia Comportamental Pragmática e Terapia Molar e de Autoconhecimento, além da literatura acerca do Acompanhamento Terapêutico. Para compor essa análise, foram desenvolvidas quatro categorias analíticas: conceitos centrais para o diagnóstico, estratégias de intervenção, efetividade e generalidade. A análise dos trabalhos citados apontou que a polarização, nos termos formulados acima, não acontece, pois todas as propostas programam formas garantir a generalização dos resultados. Foi possível definir, no entanto, a existência de um repertório mínimo de cliente . Esse repertório diz respeito a modelagem de comportamento verbal que permitirá ao cliente modificar, sozinho, o próprio ambiente. E essa é a justificativa do trabalho em ambiente natural, quando o cliente não tem repertório para modificar o seu próprio ambiente de forma independente, o terapeuta opera mudando o ambiente do cliente de maneira a construir uma condição de aprendizagem melhor para esse cliente. A partir disso, sugestões para pesquisas futuras são feitas ao final do trabalho
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Baguenard, Céline. "Synthèse et caractérisation d’architectures macromoléculaires complexes à base d’un bloc « stimuli-responsive »." Thesis, Lyon, INSA, 2012. http://www.theses.fr/2012ISAL0009.

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Les polymères répondant au pH ou à la température deviennent hydrophobes à partir d’un pH ou d’une température critique. Associés à un bloc polymère hydrophile, ils peuvent former des micelles réversibles en solution aqueuse en réponse à un stimulus. Cette thèse décrit principalement la synthèse par polymérisation radicalaire contrôlée de copolymères à blocs triple hydrophiles de type ABC ou ACB, composés d’un bloc très hydrophile (PEO, bloc A), d’un bloc répondant à la température et au pH (PDMAEMA, bloc B) et d’un bloc cationique (PDMAEMAquat, bloc C). Leur caractérisation par chromatographie d’exclusion stérique en phase aqueuse s’est révélée peu concluante ; c’est pourquoi nous les avons analysés par RMN diffusionnelle. D’autre part, l’auto-assemblage en solution aqueuse de ces copolymère triblocs en fonction du pH et de la température a été étudié par RMN 1H et par DLS. Par ailleurs, le bloc C, cationique, forme un complexe hydrophobe avec un polymère chargé négativement (PSS). Les objets résultant de cette complexation entre le dernier bloc du tribloc ABC et le PSS ont été caractérisés par RMN 1H, par DLS, par RMN diffusionnelle et par TEM. Leur comportement en solution aqueuse en fonction du pH et de la température a également été abordé
PH- or temperature-responsive polymers become hydrophobic from a critical pH or temperature. When they are associated to a hydrophilic block, they may respond to a stimulus by forming reversible micelles in aqueous solution. This thesis mainly deals with the synthesis by controlled radical polymerization of ABC- or ACB-type triple hydrophilic block copolymers, based on a highly hydrophilic block (PEO, A-block), a pH- and temperature-responsive moiety (PDMAEMA, B-block) and a cationic sequence (PDMAEMAquat, C-block). As their characterization by SEC in aqueous phase was not conclusive, they were therefore analyzed by diffusional NMR. In addition, their self-assembly in aqueous solution depending on pH or temperature was studied by 1H NMR and DLS. Furthermore, the cationic C-block form a so-called polyelectrolyte complex with a negatively charged polymer (PSS). Objects resulting from the complexation between the last block of ABC-triblock and PSS were characterized by 1H NMR, DLS, diffusional NMR and TEM. Their behavior in aqueous solution was also investigated depending on pH and temperature
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Michel, Eléonore. "Recouvrements à base de dextrane pour applications médicales." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCD086/document.

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L’ingénierie des biomatériaux a connu un essor prodigieux ces dernières décennies passant de matériaux simples à des structures plus complexes, particulièrement dans le domaine cardiovasculaire. Cette évolution découle de la nécessité des biomatériaux de permettre la synergie de différentes propriétés, dépendantes de leurs fonctions, qui ne sont pas forcément toutes compatibles. Historiquement, les premiers matériaux utilisés dans la conception de dispositifs médicaux étaient ceux présentant le meilleur compromis entre les propriétés physico-chimiques, mécaniques et biologiques que nécessitait leur application. Cependant, il se peut que le dispositif possède les bonnes propriétés physico-chimiques ou mécaniques, mais que sa biocompatibilité soit insuffisante induisant ainsi des complications cliniques. Afin d’améliorer ces propriétés biologiques tout en conservant les propriétés de volume du matériau, une solution est d’en modifier la surface. L’utilisation d’un revêtement permet alors de moduler la réponse biologique à l’interface biomatériau-hôte et de diminuer les effets indésirables. Ces revêtements sont optimisés selon deux critères principaux : la réponse biologique et la réponse mécanique. Pour la réponse biologique, les deux approches principales sont de mettre au point des revêtements proactifs qui engendrent l’adhérence, laprolifération ou la migration cellulaire, ou passifs, qui, principalement, sont inertes et empêchent l’adhérence de composés biologiques. Des revêtements plus complexes utilisent les deux approches permettant l’adhérence spécifique de certainescellules tout en empêchant l’adhérence d’autres composants biologiques. Cette pratique est très utile pour lutter contre la resténose, complication survenant après opération de l’athérosclérose qui obstrue les vaisseaux sanguins. Une pratique courante est la pose d’un stent qui permet d’ouvrir l’artère de nouveau et de rétablir le flux sanguin. Le phénomène de resténose obstrue de nouveau le vaisseau sanguin, majoritairement par la prolifération incontrôlée de cellules musculaires lisses. La recherche sur les revêtements contre la resténose vise à inhiber la prolifération de ces cellules tout en facilitant la ré-endothélialisation. Les revêtements permettraient alors, à la fois de favoriser l’adhérence et la prolifération de cellules endothéliales et de limiter celles des cellules musculaires lisses à la surface du stent ou en limitant toute adhérence non-spécifique. Il a été démontré lors d’études précédentes qu’un copolymère à base de dextrane et de poly(méthacrylate debutyle) (PBMA) répondait à ces critères biologiques et qu’il possédait en plus une bonne résistance à la déformation, paramètre important lié à la déformation induite lors de l’implantation d’un stent. L’approche de ce projet était d’utiliser ce copolymère comme revêtement de stent et d’en améliorer la stabilité à long terme en formant des liens covalents avec le substrat. Pour ce faire, cela nécessitait l’activation de la partie dextrane du copolymère afin de pouvoir le greffer au substrat. Il était important de vérifier pour chaque étape l’influence des modifications effectuées sur les propriétés biologiques et mécaniques des matériaux obtenus, mais aussi d’un point de vue de la chimie, l’influence que cette modification pouvait induire sur la réaction decopolymérisation
The last decades have witnessed the remarkable growth of biomaterial science and engineering field, especiallyfor cardiovascular applications, for which devices have evolved from simple material to complex structures.This development has stemmed from the necessity for biomaterials to exhibit different properties, related totheir function, which are not always inherently compatible. Historically, the first materials selected for medicaldevices conception were the ones exhibiting the best compromise between all the physicochemical, mechanicaland biological requirements. Nevertheless, while physicochemical and mechanical properties are often handilycombined, the development of materials which also possess suitable biological properties have proved to bemuch more challenging, leading to clinical complications.Surface modification represents a valid solution to improve the biological performances of medical deviceswhile maintaining the bulk properties of the material. Biomaterial coatings may modulate the biologicalresponse at the biomaterial-host interface and decreases the undesirable effects. Coatings have been optimizedin regards to two main aspects: the biological response and the mechanical response. For the biologicalresponse, the two main approaches consist in 1) inducing cell adhesion, proliferation or migration with proactivecoatings and 2) using inert material, mostly, and avoiding the adhesion of any biological componentswith passive coatings.More complex coatings include the two approaches, allowing the adhesion of a specific type of cell whilerepelling other biological components adhesion. This method has been very useful against the restenosisphenomenon which obstructs blood vessels. A common practice is vessel stenting, a procedure that enables thereopening of the vessel and the restoration of the blood flow. Restenosis causes the new narrowing of the vessel,mostly due to uncontrolled smooth muscle cell proliferation. Researchers looked for coatings capable oflimiting the restenosis occurrence by inhibiting this cell proliferation along with facilitating the reendothelialization.Thus, the coatings would be able to improve endothelial cells adhesion and proliferation andto inhibit smooth muscle cells ones as well as avoiding non-specific adhesion.Previous studies showed that a copolymer made of dextran and poly(butyl methacrylate) (PBMA) demonstratedsuch biological properties and a good resistance to deformation, which is an important parameter related to thedeformation implied in a stent implantation. In this work, the approach was to use this copolymer as a stentcoating and to increase its long-term stability by providing covalent bonds with the substrate. To do so, thedextran part of the copolymer firstly needed to be activated in order to be grafted to the surface. Thus, it wasimportant to ascertain the influence of the multiple modifications on the biological and mechanical propertiesof the resulting materials at each step, but also towards a chemical point of view, the influence that thesemodifications may have on the subsequent copolymerization
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Chalasani, Sri Lakshmi. "RESOLUTION OF PROXIMAL OXIDATIVE BASE DAMAGE AND 3′-PHOSPHATE TERMINI FOR NONHOMOLOGOUS END JOINING OF FREE RADICAL-MEDIATED DNA DOUBLE-STRAND BREAKS." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5237.

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Clustered damage to DNA is a signature mark of radiation-induced damage, which involves damage to the nucleobases and/or DNA backbone. Double-strand breaks created by damaging agents are detrimental to cell survival leading to chromosomal translocations. Normal cells employ Non-homologous end-joining because of its faster kinetics, to suppress chromosomal translocations. However, the presence of complex DNA ends constitutes a significant challenge to NHEJ. Location of Thymine glycol (Tg) at DSB ends was a potential hindrance to end joining. The substrate with Tg at the third position (Tg3) from the DSB joined better than when present at the fifth position (Tg5). However, hNTH1 assay showed Tg5 to be a better substrate than Tg3 for BER, potentially explaining the increased Tg removal and decreased end joining of Tg5 in extracts. Nonetheless, there appeared to be no preference in the susceptibility of 5’-Tg substrates with Tg at the second and third positions from DSB ends. Polynucleotide kinase phosphatase is crucial in restoring the 3′ hydroxyl, and 5′ phosphate ends at strand breaks. No other enzyme is known to possess PNKP’s activity in mammalian cells at DSBs. Experiments done with PNKP knockout cells have shown some activity similar to PNKP, which appeared to be a part of NHEJ and was not pharmacologically inhibited by PNKP inhibitor. Additionally, core NHEJ factors XRCC4 and XLF influenced the activities of PNKP. Overall, these experiments suggest that Tg repair is dependent on the position from DSB and an alternative enzyme processes 3′- PO, and 5′-OH ends.
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Álvares, Antonio Carlos Teixeira. "Inovação horizontal: um modelo ambidestro de gestão da inovação com base em um caso brasileiro." reponame:Repositório Institucional do FGV, 2018. http://hdl.handle.net/10438/25712.

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Esta pesquisa trata da questão dos efeitos provocados pela busca da inovação a partir de todas as pessoas da organização, particularmente da possibilidade da organização se tornar inovadora, assim entendido como capaz de produzir sistematicamente inovações de qualquer natureza e magnitude. Tal questão é relevante pois a inovação a partir de todas as pessoas de uma organização, praticamente não tem sido estudada pelos especialistas em inovação. Apesar de muito abordada pelo movimento de qualidade no tema de melhoria continua via sistemas de sugestões do tipo kaizen. A denominação Inovação Horizontal foi criada pelo autor para designar as inovações que se originam a partir de todos os funcionários da organização, usualmente a partir de programas internos de sugestões. Os sistemas internos de sugestões produzem basicamente inovações incrementais, denominadas pelos especialistas em qualidade como melhorias contínuas. Alguns autores apresentaram no passado a teoria de que novações incrementais competem com as inovações radicais. Em contraposição foi criado o conceito de ambidestria segundo o qual as organizações inovadoras produzem tanto inovações radicais quanto incrementais. A presente pesquisa a foi baseada em estudo de caso único de uma empresa de um setor maduro (metalurgia) que pratica Inovação Horizontal (a partir de todas as pessoas). Foram entrevistados dezoito gestores, todos os quatro diretores executivos, dez gerentes, dois coordenadores gerais e dois pesquisadores aposentados. O resultado indicou que a organização é inovadora sistemática, tendo criado um modelo de gestão da inovação ambidestro que produz sistematicamente inovações incrementais e radicais, tanto de produtos como de processo e gestão.
This research deals with the effects caused by the search for innovation from all the people of the organization, particularly the possibility of the organization becoming innovative, understood as capable of systematically producing innovations of any nature and magnitude. This issue is relevant because innovation from all the people of an organization, practically has not been studied by the experts in innovation. Although much approached by the movement of quality in the theme of continuous improvement via kaizen type suggestion systems. The denomination Horizontal Innovation was created by the author to designate the innovations that originate from all the employees of the organization, usually from internal programs of suggestions. Internal feedback systems basically produce incremental innovations, called by quality experts as continuous improvements. Some authors have in the past presented the theory that incremental innovations compete with radical innovations. In contrast, the concept of ambidexterity was created whereby innovative organizations produce both radical and incremental innovations. The present research was based on a single case study of a company from a mature sector (metallurgy) that practices Horizontal Innovation (from all people). Eighteen managers, all four executive directors, ten managers, two general coordinators and two retired researchers were interviewed. The result indicated that the organization is a systematic innovation, having created an ambidextrous innovation management model that systematically produces incremental and radicals innovations, of product, process and management.
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Ferreira, Adriana de Souza Sergio. "Implante permanente de sementes de iodo e prostectomia radical em portadores de câncer de próstata: análise comparativa de uma coorte de base hospitalar." Universidade Federal de Juiz de Fora (UFJF), 2010. https://repositorio.ufjf.br/jspui/handle/ufjf/2610.

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Este estudo teve como objetivo analisar e comparar a sobrevida livre de recidiva bioquímica em cinco anos e fatores prognósticos em pacientes portadores de câncer de próstata submetidos à braquiterapia ou cirurgia radical. Foram analisados 129 pacientes com câncer de próstata, destes 64 foram submetidos à braquiterapia permanente com sementes de Iodo 125 e 75 pacientes foram tratados com prostatovesiculectomia radical, no período de janeiro de 2002 a dezembro de 2005, em um hospital da rede privada da cidade de Juiz de Fora-MG. As principais variáveis analisadas, coletadas dos prontuários dos pacientes, foram: idade, data de nascimento, PSA inicial, escore de Gleason à biópsia prostática e na peça cirúrgica para os pacientes operados, estadiamento clínico e patológico para os casos cirurgicos, volume da próstata ao pré-planejamento e no momento da braquiterapia, atividade das sementes de Iodo 125 e dosagens seriadas de PSA após o tratamento. Os pacientes foram classificados, segundo D’Amico, em grupos de risco: baixo, intermediário e alto. A recidiva bioquímica foi definida como níveis de PSA> 0,4ng/ml para os casos de prostatectomia radical e três elevações consecutivas de PSA para os pacientes implantados (ASTRO). Para estudo do efeito do tratamento na sobrevida livre de recidiva bioquímica foram geradas curvas de Kaplan-Meier, e teste de log-rank foi usado para determinar diferenças entre as curvas. A influência de múltiplas variáveis na sobrevida livre de recidiva bioquímica, como Gleason, estadiamento, iPSA, categoria de risco e idade foram estimados por regressão de Cox. No primeiro artigo, foi observada taxa de sobrevida livre de recidiva bioquímica superior (p=0,0056) para os pacientes submetidos à braquiterapia 79,70% (IC95%:66,87-87,99) quando comparado aos pacientes submetidos à cirurgia 44,30% (IC95%:23,28-63,47) sendo identificados como fatores prognósticos associados de forma independente à sobrevida livre de recidiva bioquímica a modalidade terapêutica (HR= 3,33 ;IC95% :1,41-7,88), os níveis séricos de iPSA (HR=2,54;IC95%:1,11-5,78) e a categoria de risco (HR=4,18 ;IC95%:1,89-9,23). No segundo artigo, que avaliou somente os pacientes submetidos à braquiterapia, foi verificada uma taxa de sobrevida livre de recidiva bioquimica em cinco anos, significativamente superior (p=0,0012) para os pacientes do grupo de baixo risco 91,6% (IC 95%:75,92-97,24), quando comparada com àquela dos pacientes do grupo de risco intermediário/alto 59,19% (IC 95%:36,00-76,40). A sobrevida livre de recidiva bioquimica também foi significativamente superior nos pacientes com iPSA ≤ 10ng/ml (p=0,0084) e com escore de Gleason ≤ 6 à biópsia prostática (p=0,0057). Na análise multivariada, o risco de falha bioquímica também se manteve maior nos pacientes que pertenciam ao grupo de risco moderado/alto e para pacientes com iPSA superior a 10ng/ml. Os dados de sobrevida livre de recidiva bioquimica em cinco anos, para os pacientes desta análise, tratados com braquiterapia, foram comparáveis aos da literatura.
This study aimed to analyze and compare the biochemical relapse-free survival at five years and prognostic factors in patients with prostate cancer undergoing radical surgery or brachytherapy. We analyzed 129 patients with prostate cancer, these 64 underwent brachtherapy with permanent seeds implantation and 75 patients were treated with radical prostatectomy, from January 2002 to December 2005 in a private hospital network in the city of Juiz de Fora-MG. The main variables analyzed were collected from medical records and were: age, date of birth, initial PSA, Gleason score of prostate biopsy and of surgical specimens, clinical and pathologic staging on surgical cases, the prostate volume pre-planning and at the time of brachytherapy, seed activity of lodine 125 and serial measurements of PSA after treatment. Patients were classified according to D’Amico, at risk groups; low, intermediate and high. The biochemical recurrence was defined as PSA levels>0.4 ng/ml for cases of radical prostatectomy and three consecutive elevations of PSA for patients implanted (ASTRO). For the study of the effect of the treatment on biochemical relapse-free survival Kaplan-Meier curves were generated, and log rank test was used to determine the differences among the curves. The influence of multiple variables in the biochemical relapse-free survival as age, initial PSA, Gleason score, staging and risk category was estimated by Cox regression. In the first article, was observed rate of biochemical relapse-free survival superior (p = 0.0056) for patients undergoing brachytherapy 79.70% (CI95% :66,87-87, 99) when compared with patients undergoing surgery 44.30% (CI95% :23,28-63, 47) and were identified as prognostic factors independently associated with survival free of biochemical recurrence modality therapy (HR = 3.33, CI95% :1,41-7 88), serum levels of IPSA (HR = 2.54, CI95% :1,11-5, 78) and risk category (HR = 4.18, CI95% :1,89-9, 23). In the second article, which evaluated only the patients who underwent brachytherapy, there was a rate of biochemical relapse-free survival at five years, significantly higher (p = 0.0012) for patients with low-risk group 91.6% (CI 95% :75,92-97, 24), when compared with that of patients in the intermediate/high risk group 59.19% (CI95% :36,00-76, 40).The biochemical relapse-free survival was also significantly higher in patients with IPSA ≤ 10ng/ml (p = 0.0084) and Gleason score ≤ 6 on prostate biopsy (p = 0.0057). In multivariate analysis, the risk of biochemical failure also remained higher in patients who belonged to the group of moderate / high risk and patients with IPSA more than 10ng/ml. Data from biochemical relapse-free survival at five years for the patients of this analysis were comparable to literature.
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Books on the topic "Base radical"

1

Caneba, Gerard. Emulsion-based Free-Radical Retrograde-Precipitation Polymerization. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2011.

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Caneba, Gerard, and Yadunandan Dar. Emulsion-based Free-Radical Retrograde-Precipitation Polymerization. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-19872-4.

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Radical, Partido Liberal. Bases para un gobierno nacional. [Asunción]: El Partido, 1987.

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Schapiro, Herb. The love song of Saul Alinsky: An entertainment in two acts based on his life. New York: Samuel French, 2007.

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Schapiro, Herb. The love song of Saul Alinsky: An entertainment in two acts based on his life. New York: Samuel French, 2007.

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The love song of Saul Alinsky: An entertainment in two acts based on his life. New York: Samuel French, 2007.

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The naked Anabaptist: The bare essentials of a radical faith. Scottdale, Pa: Herald Press, 2010.

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Murray, Stuart. The naked Anabaptist: The bare essentials of a radical faith. Scottdale, Pa: Herald Press, 2010.

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Fischer, H., ed. Nitroxide Radicals and Nitroxide Based High-Spin Systems. Berlin/Heidelberg: Springer-Verlag, 2005. http://dx.doi.org/10.1007/b83037.

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Partido Liberal Radical Auténtico (Paraguay). Programa de gobierno: Bases para un gobierno de unidad nacional, 1993-1998. [Asunción]: P.L.R.A., 1993.

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Book chapters on the topic "Base radical"

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Simic, Michael G., and Slobodan V. Jovanovic. "Free Radical Mechanisms of DNA Base Damage." In Mechanisms of DNA Damage and Repair, 39–49. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4615-9462-8_5.

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Fuciarelli, A. F., W. F. Blakely, B. J. Wegher, and M. Dizdaroglu. "Radical-Induced Base Damage in Aqueous DNA Solutions." In The Early Effects of Radiation on DNA, 405–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-75148-6_44.

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Rippingale, Julie. "In Pursuit of a Common Values Base for Working with Young People in Formal, Informal and Social Learning." In Socially Just, Radical Alternatives for Education and Youth Work Practice, 127–44. London: Palgrave Macmillan UK, 2015. http://dx.doi.org/10.1057/9781137393593_7.

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Luks, Eugene, and Akos Seress. "Computing the fitting subgroup and solvable radical of small-base permutation groups in nearly linear time." In Groups and Computation II, 169–81. Providence, Rhode Island: American Mathematical Society, 1997. http://dx.doi.org/10.1090/dimacs/028/12.

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Röttger, Katharina, and Friedrich Temps. "Detection of the G(–H)• Radical in the Electronic Deactivation of the G–C Watson-Crick Base Pair." In Springer Proceedings in Physics, 514–16. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-13242-6_125.

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Olinski, Ryszard, Pawel Jaruga, and Tomasz Zastawny. "Estimation Of Free Radical Induced DNA Base Damages in Cancerous- and HIV Infected Patients and in Healthy Subjects." In Advances in DNA Damage and Repair, 353–69. Boston, MA: Springer US, 1999. http://dx.doi.org/10.1007/978-1-4615-4865-2_29.

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jagodzinski, jan, and Jason Wallin. "Questioning the Radical Edge." In Arts-Based Research, 85–110. Rotterdam: SensePublishers, 2013. http://dx.doi.org/10.1007/978-94-6209-185-6_4.

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Becker, Thomas, and Volker Weispfenning. "Decomposition, Radical, and Zeroes of Ideals." In Gröbner Bases, 335–421. New York, NY: Springer New York, 1993. http://dx.doi.org/10.1007/978-1-4612-0913-3_9.

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Bauer, Andrea S., and David Ring. "Radial Head Fractures." In Evidence-Based Orthopedics, 397–402. Oxford, UK: Wiley-Blackwell, 2011. http://dx.doi.org/10.1002/9781444345100.ch45.

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Caneba, Gerard, and Yadunandan Dar. "Radical-Containing Polymer Emulsions." In Emulsion-based Free-Radical Retrograde-Precipitation Polymerization, 109–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-19872-4_10.

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Conference papers on the topic "Base radical"

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Lipinski, Katherine P., Randall S. Ruffner, Karthik S. Shastri, Lisa Galati, and Carlos D. Pinheiro-Neto. "Oropharyngeal Reconstruction after Transoral Robotic Radical Tonsillectomy: When Reconstruction is Indicated?" In 30th Annual Meeting North American Skull Base Society. Georg Thieme Verlag KG, 2020. http://dx.doi.org/10.1055/s-0040-1702622.

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Morino, K., N. Kawagoishi, K. Yamane, and K. Fukada. "Fatigue strength of a radical nitrided Ni-base super alloy." In CONTACT/SURFACE 2009. Southampton, UK: WIT Press, 2009. http://dx.doi.org/10.2495/secm090161.

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Kaiser, Sascha, Arne Seitz, Patrick Vratny, and Mirko Hornung. "Unified Thermodynamic Evaluation of Radical Aero Engine Cycles." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-56313.

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The Joule-/Brayton thermodynamic cycle is the base cycle of all major contemporary aero engines. Over the decades, the achievement of further significant improvements has become progressively challenging, and the increase of efficiency approaches physical limitations. In order to meet the ambitious long-term emission reduction targets, the introduction of radical new propulsion system concepts is indispensable. Various cycles promising significant efficiency improvements over the conventional Joule-/Brayton-cycle are being examined by the engine community. However, as no clear favorite has emerged from these potential technical solutions, a transparent methodological approach for the consistent evaluation of the concepts is necessary. Consistent thermodynamic description and performance metrics for three engine cycles are presented in this paper: The turbofan as reference and two radical engine cycles, namely the composite cycle and the cycle-integrated parallel hybrid. Laws for the estimation of component performance for large parametric variations are introduced. A method for the estimation of power plant system mass for the investigated engine cycles is proposed to evaluate fuel burn reduction. The studies substantiated that the turbofan improvement potential is saturating. The composite cycle engine offers a tremendous potential for fuel burn improvement of 24.5% over state of the art turbofan engines, which allows meeting the emission reduction targets in 2035. The cycle-integrated parallel hybrid engine improves the turbofan moderately with year 2035 technology, but is not capable of meeting the corresponding emission reduction targets on a short-to-medium range aircraft platform.
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Milanovic, Žiko, Ana Kesic, Edina Avdovic, Jelena Đorovic Jovanovic, and Dejan Milenkovic. "UTICAJ pH VREDNOSTI NA ANTIRADIKALSKI KAPACITET 4,7- DIHIDROKSIKUMARINA." In XXVI savetovanje o biotehnologiji sa međunarodnim učešćem. University of Kragujevac, Faculty of Agronomy, 2021. http://dx.doi.org/10.46793/sbt26.481m.

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The mechanisms of antiradical activity of 4,7-dihydroxycoumarin against peroxy (HOO•) radical were investigated. For this purpose were used sophisticated computational methods. Investigation was performed in the water, at different pH values (0-14). Acid-base species, which are represented in diverse molar fraction (f) at different pH values, contribute to a comprehensive examination of antiradical capacity. An overall rate constant (koverall) of the favorable reaction pathways (HAT and RAF) of 2.07×102 M-1s-1 at physiological pH indicates a moderate ability to neutralization HOO• radicals. A value of 1.05×103 M-1 s-1 occurring at pH > 10 indicates a maximum antiradical capacity of 4,7-dihydroxymumarin against the HOO• radical.
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Barbeau, Dennis E. "Fast CE™ — A Radical Approach to Concurrent Engineering." In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-354.

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This paper describes the status and potential for a fast time-to-market concurrent engineering process. The principles have been developed by the author over a 25 year learning process and used effectively on a variety of programs. Fast CE™ is fundamentally predicated on integration of the manufacturing and engineering processes at the conceptual design phase. Commencement at this early date is critical — 80 to 90% of the inherent production unit cost is locked in place during this process. Subsequent to development of an integrated design strategy, both producibility and functional product development evolve in parallel using a “model-centric” approach to maintain the integrity of all elements of the program. Fast CE™ not only eliminates the use of drawings, it requires that they not be used in any capacity except as a convenience reference. This provides tight control over a common data base that directly links all of the activities necessary to design and produce a product. The result is a significant reduction in cost and schedule, with gains in all of the processes required to bring a product to market. Drawing elimination in itself can amount to a savings of as much as one third of the total design cost. The activities previously supported by drawings — quality assurance, for example — are managed through simpler, more functionally oriented processes. The author describes the elements of Fast CE™ and the radical changes required in certain areas. Historical background traces development of the processes, providing perspective on the strategies and the issues faced and overcome, and leading to the issues currently faced in attainment of its full potential. The cost and schedule gains identified require cultural as well as operational changes. The more radical of these changes present a management challenge to any organization intent on gaining the full spectrum of benefits.
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Röttger, Katharina, and Friedrich Temps. "Detection of the G(–H)● Radical in the Electronic Deactivation of the G–C Watson-Crick Base Pair." In International Conference on Ultrafast Phenomena. Washington, D.C.: OSA, 2014. http://dx.doi.org/10.1364/up.2014.07.mon.p1.20.

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Cheenkachorn, Kraipat, Wallis A. Lloyd, and Joseph M. Perez. "Use of Pressurized Differential Scanning Calorimetry (PDSC) to Evaluate Effectiveness of Additives in Vegetable Oil Lubricants." In ASME 2003 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ices2003-0657.

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Use of renewable resources to replace petroleum base stocks in lubricants is attractive. Research on additives enhanced by current advances in genetic and chemical modifications has resulted in improved oxidative stability of vegetable oils. Like most oxidation processes, the oxidative degradation of vegetable oils is complex. The auto-oxidation free radical mechanisms and hydroperoxide theories of oxidation have been well studied. Factors that influence the degradation of oils include temperature, surface reactivity, rates of formation of radicals, chemical composition factors such as olefin and aromatic content and additive effectiveness. This uses pressurized differential scanning calorimetry to evaluate the oxidative stability of four biodegradable fluids with and without additives. The oleic acid content of the four fluids ranged from 83 to 23 percent. Reaction kinetics are used to explain observed differences in phase transformation and polymerization reactions. Additive selection to obtain maximum effectiveness in the base stocks is reported.
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Wang, Jifen, Huaqing Xie, Zhong Xin, Yang Li, Lifen Chen, and Na Xu. "Experimental Study on Thermal Property of Alkali Treated CNT-Based Composite as Phase Change Materials." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-10183.

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The nanocomposites were prepared by adding the multi-walled carbon nanotubes (CNTs) to the melting palmitic acid to improve the thermal transfer property. Mechanochemical reaction was used to treat CNTs for dispersing into organic matrix easily. The treated CNTs were introduced hydoxide radical functional groups on the surfaces during ball milling with the potassium hydroxide. And they were successfully dispersed into the palmitic acid matrix without any surfactant. The resulted nanocomposites were stable and homogeneous. The thermal conductivities and latent heat capacities of these nanocomposites were measured using a transient hot wire apparatus and a differential scanning calorimetric instrument. Nanotube composites, containing a small amount of CNTs, have substantially higher thermal conductivities than the base palmitic acid matrix, with the enhancement increasing with the mass fraction of CNTs in both liquid state and solid state. While the latent heat capacities turned out a reverse with the CNT loadings.
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Hedman, Paul O., Geoffrey J. Sturgess, David L. Warren, Larry P. Goss, and Dale T. Shouse. "Observations of Flame Behavior From a Practical Fuel Injector Using Gaseous Fuel in a Technology Combustor." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-389.

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This paper presents results from an Air Force program being conducted by researchers at Brigham Young University (BYU) Wright-Patterson Air Force Base (WPAFB), and Pratt and Whitney Aircraft Co (P&W). This study is part of a comprehensive effort being supported by the Aero Propulsion and Power Laboratory at Wright-Patterson Air Force Base, and Pratt and Whitney Aircraft, Inc. in which simple and complex diffusion flames are being studied to better understand the fundamentals of gas turbine combustion near lean blowout. The program’s long term goal is to improve the design methodology of gas turbine combustors. This paper focuses on four areas of investigation: 1) digitized images from still film photographs to document the observed flame structures as fuel equivalence ratio was varied, 2) sets of LDA data to quantify the velocity flow fields existing in the burner, 3) CARS measurements of gas temperature to determine the temperature field in the combustion zone, and to evaluate the magnitude of peak temperature, and 4) two-dimensional images of OH radical concentrations using PLIF to document the instantaneous location of the flame reaction zones.
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Shnaras, E. S. "ASPECTS OF INNOVATIVE DEVELOPMENT OF AGRARIAN EDUCATION AFTER THE PANDEMIC." In INNOVATIVE TECHNOLOGIES IN SCIENCE AND EDUCATION. DSTU-Print, 2020. http://dx.doi.org/10.23947/itno.2020.383-387.

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Training of new generation personnel in the context of traditional and distance learning remains relevant in our century of high-speed and nano-technologies, robotic equipment and combined agricultural complexes. The innovative development of the agro-industrial complex is based on modern methods of production and a radical change in the quality of management not only of technological processes, but also of decision-making processes at all stages of organizing the production of agricultural products. Today, not all higher educational institutions in the field of the agro-industrial complex can claim to be in relative compliance with the production requirements for the training of specialists, therefore, modernization of education is required, which provides for the renewal of the facility, that is, bringing it in line with new requirements, norms, technical conditions and quality indicators. The article examines aspects of the innovative development of agricultural education and proposes priority directions for the integration activities of an agricultural university as a multidisciplinary educational center or complex, taking into account the tasks set, which are implemented through the modernization of the educational process and the educational and production base for conducting educational and practical classes at the university.
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Reports on the topic "Base radical"

1

Buhmann, Martin D., and Amos Ron. Radial Base Functions: Lp-approximation Orders with Scattered Centres. Fort Belvoir, VA: Defense Technical Information Center, January 1994. http://dx.doi.org/10.21236/ada274682.

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2

Jing, Y. Polar, Functional Diene-Based Materials: Free Radical Polymerization of 2-Cyanomethyl-1,3-Butadiene. Office of Scientific and Technical Information (OSTI), September 2000. http://dx.doi.org/10.2172/764681.

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3

Wozniak, Nicholas, Emily Shemon, James Grudzinski, and Benjamin Spencer. Assessment of MOOSE-Based Tools for Calculating Radial Core Expansion. Office of Scientific and Technical Information (OSTI), July 2021. http://dx.doi.org/10.2172/1808314.

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4

Haddon, Robert C. Final Report for DOE Grant 97-00, Solid state electronic structure and properties of neutral carbon-based radicals. Office of Scientific and Technical Information (OSTI), November 2001. http://dx.doi.org/10.2172/805758.

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5

Havrlant, David, and Abdulelah Darandary. Economic Diversification under Saudi Vision 2030. King Abdullah Petroleum Studies and Research Center, April 2021. http://dx.doi.org/10.30573/ks--2021-dp06.

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The last decade has brought a row of substantial changes that have profound implications for the traditional hydrocarbon resource-rich economies. Economic conditions may change radically either throughout a decade or within months. The question is whether there is no other option for a hydrocarbon resource-rich economy than to be held hostage to the fluctuations in global oil prices. The general answer to a changing environment is: Adapt! From the macroeconomic perspective, this means diversifying the economy to broaden the income base and significantly reduce the dependence on oil revenues. The Saudi Vision 2030 represents a complex plan for substantial socioeconomic adjustments that are about to move the economy toward a more diversified and sustainable one. This discussion paper examines the preferred diversification paths for the Saudi economy in more detail, with a focus on the foreseen adjustments in the sectoral composition of the economy along with broader macroeconomic shifts. The evaluation of the foreseen diversification impacts is based on the updated Vision 2030 Input-Output Table that maps the changing structure of the Saudi economy over the coming decade. We discuss the assumed expansion of the diversification frontrunners, their changing contribution to the overall economic activity and identify the preferred diversification paths for the Saudi economy. The advances in economic diversification are measured by applying the Shannon-Weaver index to sectoral GDP and household income. The expected sectoral changes are wide-reaching, so the basic macroeconomic relations are also subject to adjustments. We also conduct a sensitivity analysis to examine the effects of the foreseen diversification on the resilience of the Saudi economy to external shocks.
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