Spelling suggestions: "subject:"radical"" "subject:"eadical""
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A flash photolysis study of atom plus reactionsBrouard, M. January 1986 (has links)
No description available.
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Magnetic field effects on electron transfer reactions in photosynthetic bacteriaCarpenter, Joanna Katharine Hicks January 1997 (has links)
No description available.
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Synthesis of ring systems via radical reactionsRobertson, G. M. January 1985 (has links)
No description available.
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Application of UV curing to the preparation of composite materialsMouillat, Claire G. J. January 1997 (has links)
No description available.
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REMPI studies of molecular reaction dynamicsBlack, J. F. January 1987 (has links)
No description available.
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Heterocycle synthesis by hydrogen atom transfer and cyclisationPillai, Jayasheela January 1998 (has links)
No description available.
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John Steinbeck As a Radical NovelistJasinski, Shawn 24 June 2008 (has links)
The radical literary tradition of the 1930‟s inspired many American authors to become more concerned with the struggle of the proletariat. John Steinbeck is one of these authors. Steinbeck‟s novels throughout the 1930‟s and 1940‟s display a lack of agreement with the common Communist principles being portrayed by other radical novelists, but also a definite alignment with several more basic Marxist principles. The core of his radical philosophy comes in the form of his interest in group-man or the phalanx. An interest that is rather uncommon for the period, as most radical novelists were more concerned with illustrating the solitary nature of the proletarian worker. Over the course of his career this philosophy evolves, as can be illustrated through an analysis of In Dubious Battle, The Grapes of Wrath, and Cannery Row. In Dubious Battle is highly critical of Communist labor organizers, and sets Steinbeck apart form the radical tradition by questioning rather than supporting their motivation. The labor organizers manipulate the phalanx in this novel, and Steinbeck leaves the reader with the impression that the group-man is being corrupted. The Grapes of Wrath is also a socially motivated novel, with an abundance of Marxist undertones, but most importantly the novel provides Steinbeck with a better medium within which he can further examine the phalanx. Throughout this novel Steinbeck remains separate from other propagandists, as he supports his own agenda rather than that of the Party. Steinbeck‟s communal exploration comes to fruition in Cannery Row. While the novel has received a relatively small amount of critical attention due to the common presumption that Steinbeck intended the work to be a diversion from war, the characters of Cannery Row provide Steinbeck with the ultimate vehicle to illustrate the importance of the phalanx. Together these novels represent the evolution of Steinbeck‟s radical philosophy, particularly as it pertains to his vision of communal existence. While this vision of collectivity is what aligns Steinbeck with the most basic of Marxist principles, the mysticism he surrounds it with is what serves to set him apart from the more utilitarian communist appreciation of the phalanx. This argument will come largely in the form of analysis of Steinbeck‟s mouthpieces, which are characters in the novels that illustrate Steinbeck‟s philosophy either through speech or action. The conclusion of the analysis will show that Steinbeck is definitely a radical novelist, even though he is sometimes at odds with the tenets of the greater radical tradition.
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Derivations mapping into the radical27 May 2010 (has links)
M.Sc. / One of the earliest results (1955) in the theory of derivations is the celebrated theorem of I. M. Singer and J. Wermer [14] which asserts that every bounded derivation on a commutative Banach algebra has range contained in the radical. However, they immediately conjectured that their result will still hold if the boundedness condition was dropped. This conjecture of Singer and Wermer was confirmed only in 1988, by M. P. Thomas [23], when he showed that every derivation (bounded or unbounded) on a commutative Banach algebra has range contained in the radical. But it is not known whether an analogue of the Kleinecke-Shirokov Theorem holds for everywhere defined unbounded derivation.
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Photoionisation et spectrométrie de masse : un nouvel outil pour l'identification de biomolécules / Photoionisation and mass spectrometry : a novel tool for the identification of biomoleculesSabir-Bagag, Aïcha 17 October 2008 (has links)
Mon travail de thèse a été entièrement dévoué à l’étude d’une récente technique d’ionisation en spectrométrie de masse : la photoionisation à pression atmosphérique (APPI). Ce travail est développé sur deux axes principaux. D’une part, il vise à appliquer cette méthode d’ionisation à de nouvelles familles de molécules et d’en élargir le cas échéant le domaine d’application. D’autre part et parallèlement à cela, nous nous sommes attachés à l’étude des mécanismes de formation des ions ainsi qu’à l’élucidation des voies de fragmentation. En effet, ces dernières se révèlent souvent intensives et particulières. Les résultats obtenus dans le cadre du premier axe de recherche de ce travail de thèse offrent de nouvelles solutions pour mieux comprendre le comportement de molécules biologiques sous irradiation UV et à pression atmosphérique. En effet, nous avons pu démontrer que la photoionisation à pression atmosphérique pouvait s’étendre à d’autres classes de composés que ceux initialement pressentis et plus particulièrement à des biomolécules polaires et de haut poids moléculaire tels que les acides nucléiques, peptides, les peptides, etc. De plus, ce travail a permis de démontrer l’impact du milieu (solvant) sur le mécanisme de formation des ions sous irradiation UV. Ainsi l’étude et la connaissance des mécanismes fondamentaux de formation des ions en APPI a visé in fine au contrôle de la formation des ions précurseurs et par voie de conséquence, à celui des fragments générés en source. Nous avons observé des ions fragments radicalaires d’un type nouveau, jamais observé auparavant avec les sources d’ions connues L’originalité et le caractère résolument novateur de cette expérience nous ont amené à transférer cette expérience sur une ligne de lumière du Synchrotron SOLEIL. L’utilisation d’une source de lumière accordable en APPI va certainement renforcer la versatilité de cette source d’ions. / My PhD’s work has been completely dedicated to develop new ionization source in mass spectrometry: the atmospheric pressure photoionization (APPI). This work is developed on two main areas. On the one hand, it aims to apply this method to new family of biomolecules. On the other hand, we report a comprehensive study on the ionization mechanisms in APPI. The first part of this manuscript offers a better understanding of the behaviour of the biological molecules under VUV radiation and atmospheric pressure. Indeed, we were able to say that polar and high molecular weight biomolecules could be easily photoionizable. Moreover, this work allows studying the effect of the medium (solvent) on the photoionization mechanism to be studied. It is possible to control the orientation of the observed reactions and to choose a particular type of molecular ion. We observed extensive and peculiar fragmentations which have never been detected with classical ionization techniques. The originality and innovative approach of this experience led us to transfer it to a UV beamline of the Synchrotron SOLEIL. Using an accordable source will certainly enhance the versatility of the ion source.
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Semiquinone-Bridged bis-Dithiazolyls as Neutral Radical ConductorsYu, Xin January 2011 (has links)
Radicals are potential building blocks to prepare conductive and magnetic materials. In order to achieve high conductivity, materials displaying a large bandwidth W and a low on-site Coulomb repulsion energy U must be generated.
Semiquinone-bridged bis-1,2,3-dithiazolyl radicals (R = Cl, Ph, Me and the MeCN adduct of R = Cl) represent a new family of resonance stabilized neutral radical for use in the design of single-component conductive materials were prepared and fully characterized. In solid state these radicals remain as unassociated (monomers) in the solid state and typically form superimposed alternating π-stacks or slipped π-stacks, arranged in several different space groups. The predominate intermolecular interactions are S•••N′ and / or S•••O′ contacts, which increase the dimensionality from one dimensional π-stacked systems (i.e., poor lateral overlap) to two dimensional systems in the solid state. Thus the semiquinone-bridged bis-dithiazolyl radicals exhibit a significant decrease in activation energy (ca. 0.1 – 0.2 eV) and the conductivity is two to three orders of magnitude (ca. σ ≈ 1E-5 – 1E-2 S / cm) higher in comparison to the previously reported pyridine based systems. This high conductivity is attributed to the low on-site Coulomb repulsion energies (U) which were estimated from the solution cell potentials (EPC) obtained from CV measurements and improved bandwidth (W) from the S•••N′ and / or S•••O′ interactions. Furthermore, the all sulphur containing semiquinone-bridged bis-dithiazolyls have the lowest activation energies and the highest conductivity under ambient conditions compared with other all sulfur nitrogen based radicals known to date.
The semiquinone-bridged bis-dithiazolyl (R = Cl) orderes as spin-canted antiferromagnets, TN = 8 K, and displayed large coercivity (80 Oe). The ZFC-FC measurement at low field (i.e., H = 100 Oe) established the phase transition temperatures and the spontaneous magnetization was used to estimate the spin canting angles (~ 0.14°). In the case of R = Ph, the antiparallel alignment of the ferromagnetic coupled chains leads to a spin-canted antiferromagnet (TN = 4.5 K), which undergo a unique field induced spin flop transition. The MeCN solvated of R = Cl behaves as a simple paramagnet at room temperature with bulk antiferromagnetic interactions, but no observed magnetic ordering from 2-300 K.
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