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Kinetic Studies of Hydroxyl and Hydrogen Atom Reactions

Kinetic Studies of Hydroxyl and Hydrogen Atom Reactions

Date: May 2002
Creator: Hu, Xiaohua
Description: Gas phase kinetics of the reactions involving hydroxyl radical and hydrogen atom were studied using experimental and ab initio theoretical techniques. The rate constant for the H + H2S reaction has been measured from 298 to 598 K by the laser photolysis/resonance fluorescence (LP-RF) technique. The transition state theory (TST) analysis coupled with the measurements support the suggestion that the reaction shows significant curvature in the Arrhenius plot. The LP-RF technique was also used to measure the rate constant of the H + CH3Br reaction over the temperature range 400-813 K. TST and density functional theory (DFT) calculations show that the dominant reaction channel is Br-abstraction. The reaction H + CF2=CF-CF=CF2 was first studied by flash photolysis/resonance fluorescence (FP-RF) method. The experiments of this work revealed distinctly non-Arrhenius behavior, which was interpreted in terms of a change in mechanism. DFT calculations suggest that the adduct is CF2H-CF•-CF=CF2. At lower temperatures a mixture of this molecule and CF2•-CFH-CF=CF2 is likely. The theoretical calculations show that H atom migrates in the fluoroethyl radicals through a bridging intermediate, and the barrier height for this process is lower in the less fluorinated ethyl radical. High level computations were also employed in studies of the ...
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Kinetics and Mechanism Study of Diphenylketene Cycloadditions

Kinetics and Mechanism Study of Diphenylketene Cycloadditions

Date: August 1967
Creator: O'Neal, Hubert Ronald
Description: From a review of the published work in the field of cycloadditions, it is evident that further research is needed to establish the mechanism of ketene cycloadditions. This work was initiated with the intent of obtaining kinetic data which will contribute to the elucidation of the mechanism of ketene cycloadditions.
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Kinetics and Mechanisms of Metal Carbonyls

Kinetics and Mechanisms of Metal Carbonyls

Date: May 1998
Creator: Ladogana, Santino
Description: Pulsed laser flash photolysis with both visible and infrared detection has been applied to the study of the displacement of weakly coordinating ligands (Lw) by strongly "trapping" nucleophiles (Ls) containing either an olefinic functionality (Ls = 1-hexene, 1-decene, 1-tetradecene) or nitrogen (Ls = acetonitrile, hydrocinnamonitrile) from the photogenerated 16 electron pentacarbonylchromium (0) intermediate. 5-Chloropent-l-ene (Cl-ol), a potentially bidentate ligand, has been shown to form (ol-Cl) pentacarbonylchromium (0), in which Cl-ol is bonded to Cr via a lone pair on the chlorine, and isomerize to (Cl-ol) pentacarbonylchromium (0), in which Cl-ol is bonded to the olefinic functionality on the submillisecond time scale. This process has been studied in both the infrared and visible region employing both fluorobenzene or n-heptane as the "inert" diluent. Parallel studies employing 1-chlorobutane and 1-hexene were also evaluated and showed great similiarity with the Cl-ol system. The data supported a largely dissociative process with a possibility of a small interchange process involving the H's on the alkyl chain. Studies were also carried out for various Cr(CO)6/arene/Ls systems (arene = various alkyl or halogenated substituted benzenes). The data indicated that for both C6H5R (R=various alkyl chains) or multi-alkyl substituted arenes (i.e. o-xylene, 1,2,3-trimethylbenzene) containing an "unhindered" ring-edge, bonding ...
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Kinetics of Reactions of Substituted Group VI B Metal Carbonyls with Phosphites

Kinetics of Reactions of Substituted Group VI B Metal Carbonyls with Phosphites

Date: August 1972
Creator: Rettenmaier, Albert J.
Description: The problem with which this investigation is concerned is twofold. The initial part of the problem was to prepare a non-sterically demanding bidentate phosphine ligand, 1,2-bis-(Phosphino)ethane, (P-en), and to determine the kinetics of (P-en)Mo(CO)4 with phosphites via spectrophotometric methods in an attempt to determine if steric effects are directing the type of mechanism followed.
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Kinetics of Sulfur: Experimental Study of the Reaction of Atomic Sulfur with Acetylene and Theoretical Study of the Cn + So Potential Energy Surface

Kinetics of Sulfur: Experimental Study of the Reaction of Atomic Sulfur with Acetylene and Theoretical Study of the Cn + So Potential Energy Surface

Date: May 2013
Creator: Ayling, Sean A.
Description: The kinetics of the reaction of atomic sulfur with acetylene (S (3P) + C2H2) were investigated experimentally via the flash photolysis resonance fluorescence method, and the theoretical potential energy surface for the reaction CN + SO was modeled via the density functional and configuration interaction computational methods. Sulfur is of interest in modern chemistry due to its relevance in combustion and atmospheric chemistry, in the Claus process, in soot and diamond-film formation and in astrochemistry. Experimental conditions ranged from 295 – 1015 K and 10 – 400 Torr of argon. Pressure-dependence was shown at all experimental temperatures. The room temperature high-pressure limit second order rate constant was (2.10 ± 0.08) × 10-13 cm3 molecule-1 s-1. The Arrhenius plot of the high-pressure limit rate constants gave an Ea of (11.34 ± 0.03) kJ mol-1 and a pre-exponential factor of (2.14 ± 0.19) × 10-11 cm3 molecule-1 s-1. S (3P) + C2H2 is likely an adduct forming reaction due to pressure-dependence (also supported by a statistical mechanics analysis) which involves intersystem crossing. The potential energy surface for CN + SO was calculated at the B3LYP/6-311G(d) level and refined at the QCISD/6-311G(d) level. The PES was compared to that of the analogous reaction ...
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Kinzua Dam: a Study in the Congressional Disruption, Relocation-Resettlement, and Rehabilitation of the Seneca Nation of Indians

Kinzua Dam: a Study in the Congressional Disruption, Relocation-Resettlement, and Rehabilitation of the Seneca Nation of Indians

Date: January 1969
Creator: Verelst, Robert
Description: This thesis embraces four major topics coinciding with the four considerations designated in President John F. Kennedy's letter to President Basil Williams of the Seneca Nation and the reactions to those items generated during numerous hearings of the House Subcommittee on Indian Affairs. The four topics covered in the President's letter include the possibility of acquiring adjacent property, commonly referred to as "in lieu of" lands, to replace the Indian real estate taken for the Allegheny Reservoir; a review of the reservoir's recreational potential for the benefit of the Seneca Nation; special damages accruing to the Senecas for the loss of their land; and relocation and resettlement.
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Kleinian Groups in Hilbert Spaces

Kleinian Groups in Hilbert Spaces

Date: August 2012
Creator: Das, Tushar
Description: The theory of discrete groups acting on finite dimensional Euclidean open balls by hyperbolic isometries was borne around the end of 19th century within the works of Fuchs, Klein and Poincaré. We develop the theory of discrete groups acting by hyperbolic isometries on the open unit ball of an infinite dimensional separable Hilbert space. We present our investigations on the geometry of limit sets at the sphere at infinity with an attempt to highlight the differences between the finite and infinite dimensional theories. We discuss the existence of fixed points of isometries and the classification of isometries. Various notions of discreteness that were equivalent in finite dimensions, no longer turn out to be in our setting. In this regard, the robust notion of strong discreteness is introduced and we study limit sets for properly discontinuous actions. We go on to prove a generalization of the Bishop-Jones formula for strongly discrete groups, equating the Hausdorff dimension of the radial limit set with the Poincaré exponent of the group. We end with a short discussion on conformal measures and their relation with Hausdorff and packing measures on the limit set.
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The Klezmer Influence in Paul Schoenfield’s Klezmer Rondos

The Klezmer Influence in Paul Schoenfield’s Klezmer Rondos

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Date: December 2011
Creator: Trimble, Mark
Description: Paul Schoenfield’s Klezmer Rondos is a work for flute, male vocalist, and orchestra revised in 1994 according to the score given to me by the composer. A review of current research in klezmer heritage music is the starting point to place Klezmer Rondos in the context of art music infused with klezmer flavor. Klezmer music can be defined as the instrumental folk music of Eastern European Jews, however because of its adaptability and quality of assimilating other cultures within it, this heritage music is constantly in flux. By looking at the research in this field, I describe how the sound of klezmer music has evolved and how popular notions have been formed. The body of this research explores the main musical aspects of Klezmer Rondos that can be tied to the klezmer tradition: scales and thematic materials, improvisatory elements, ornamentation, and instrumentation. Klezmer Rondos moves beyond a simple arrangement of vernacular music for orchestra; it is a fusion of contemporary art music with the elements of klezmer style.
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Knowledge and attitudes of preservice teachers towards students who are gay, lesbian, bisexual, or transgendered.

Knowledge and attitudes of preservice teachers towards students who are gay, lesbian, bisexual, or transgendered.

Date: December 2003
Creator: Morgan, Daniel J.
Description: The study used a survey design to ascertain the levels of knowledge and attitudes of special education and non-special education preservice and inservice teachers towards students with different sexual orientations. The results of this study are based on 408 responses from preservice and inservice teachers enrolled at seven institutions of higher education within North Carolina, Virginia, and the District of Columbia offering teacher training programs in regular and/or special education. Two previously developed instruments were used to measure dependent variables in this study. Koch's modified version of The Knowledge about Homosexuality Questionnaire developep by Harris, Nightengale & Owen was used to measure the dependent variable of the preservice and inservice teacher's knowledge about homosexuality. Herek's Attitudes Toward Lesbians and Gay Men (ATLG) measured the dependent variable of attitudes towards homosexuals. The study found no significant differences reported mean scores for knowledge or attitude of homosexuality among the teacher groups surveyed: (a) special education preservice teachers, (b) non-special education preservice teachers, (c) special education inservice teachers, and (d) non-special education inservice teachers. Neither gender nor age were found to be factors in measures of knowledge or attitude of preservice or inservice teachers. Receiving prior instruction in serving the needs of GLBT ...
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Knowledge and Confidence of Speech-Language Pathologists Regarding Autism

Knowledge and Confidence of Speech-Language Pathologists Regarding Autism

Date: December 2010
Creator: Ray, Julie M.
Description: The increased prevalence rate of autism has immense implications for speech language pathologists (SLPs) who are directly involved in the education and service delivery for students with autism. However, few studies have documented the effectiveness of the knowledge and confidence of SLPs regarding autism. The purpose of this study was to measure the knowledge and confidence of SLPs regarding autism and the extent to which their educational and professional training prepared them to work effectively with this population. An online survey was administered to and returned by 336 SLPs nation-wide. Two multiple linear regressions were conducted to determine the variables that explained overall knowledge and confidence. The number of students with autism on one's caseload explained most of the variance. Independent sample t-test results depicted knowledge and confidence scores of SLPs who were behaviorally trained versus those who were not behaviorally trained. SLPs who were behaviorally trained had higher mean scores on measures of knowledge and confidence when compared to those without formal behavioral training. Finally, a bivariate correlation was conducted to explore the relationship between knowledge and confidence of SLPs, however, results were not statistically significant.
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