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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

A Comparative Study of the Stipulated, Assigned, and Acquired Duties of the Head and Assistant Football Coaches of the Class AA High Schools Within a Radius of 115 Miles of Grand Prairie, Texas

Ashton, Vernon C. January 1950 (has links)
The purposes of this study are (1) to make a comparison of the stipulated, assigned, and acquired duties of the head football coaches of Class AA high schools within a radius of 115 miles of Grand Prairie, Texas; and (2) to make a comparison of the stipulated, assigned, and acquired duties of the assistant football coaches of Class AA high schools within a radius of 115 miles of Grand Prairie, Texas.
62

Effects of the in ovo injection and dietary supplementation of L-ascorbic acid on the performance, tissue L-ascorbic acid concentrations, inflammatory response, and trachea histomorphology of Ross 708 broilers raised under normal and elevated atmospheric ammonia levels

Mousstaaid, Ayoub 06 August 2021 (has links) (PDF)
Effects of various levels of L-ascorbic acid (L-AA) (12 and 25 mg) in ovo injected at 17 and 18 days of incubation, on embryonic and posthatch physiological variables in Ross 708 broilers were investigated. There were no significant treatment effects on the hatchability or serum concentrations of L-AA in the broilers. Eye L-AA concentrations were higher, and plasma nitric oxide levels were lower in male chicks treated in ovo with 12 mg of L-AA. While exposed to elevated atmospheric NH3 levels, the in ovo injection of 12 mg of L-AA increased the body weight gain and decreased the feed conversion ratio of the broilers from 0 to 28 days of age (doa). Decreased tracheal attenuation incidence was also experienced at 0 doa in the in ovo injected L-AA groups, and tracheal inflammation was significantly reduced at 28 doa in response to the in ovo injection of 12 mg of L-AA.
63

Celogentin C and Thioviridamide: Synthetic and Structural Studies

Litvinov, Dmitry Nikolayevich 07 June 2010 (has links) (PDF)
Project I Celogentin C, isolated by Kobayashi from the seeds of Celosia argentea in 2001 exhibits strong inhibitory behavior towards polymerization of tubulin – globular protein, which plays crucial role during the cell division cycle. We have attempted synthesis of the left-hand ring of celogentin C via the intramolecular alkylation and the Knoevenagel condensation strategies. Utilizing synthetic methodologies in the field of nitroacetyl chemistry, developed by Kornblum and Rajappa we have successfully prepared the intermolecular Knoevenagel condensation product – the late-stage precursor to the left-hand ring of celogentin C. Synthesis of this key intermediate subsequently led to the preparation of the left-hand ring and the total synthesis of celogentin C by other members of Castle's group. Project II Thioviridamide is the potent apoptosis inducer isolated by Hayakawa from the bacterial broth of Streptomyces olivoviridis. Unusual structural features of the thioviridamide macrocycle contain two novel amino acids, never before encountered in a natural product - S-(2-aminovinyl)cysteine (avCys) and β-hydroxy-N1,N3-dimethylhistidinium (hdmHis). No stereochemical information except for the Z-configuration of the β-thioenamide linkage was reported in the literature. We have performed a computational study to predict the thioviridamide stereochemistry. Initial populations of conformers for the likely candidate structures were produced using OPLS-AA force field. Prediction of the NMR properties was accomplished at the mPW1PW91/6-311+G(2d,p) level of theory with the polarizable continuum model of salvation. Utilizing Boltzmann averaging and statistical analysis we have determined that the only possible cases of stereochemical inversion occur at the sites of the two novel amino acids. Project III Model studies towards the synthesis of the β-thioenamide subunit of thioviridamide were performed. The radical addition reaction of thiyl radicals to ynamides produces Z- (kinetic products) or E- β-thioenamides (thermodynamic products) depending on the reaction conditions. Two distinct sets of reaction conditions allowing kinetic or thermodynamic control of β-thioenamide formation were developed. Synthesis of the model β-thioenamide subunit of thioviridamide was attempted.
64

An analysis of Ohio Music Educators Association’s 2009 class AA and A choral music with regard to the tessitura demands for the high school male voice

Hiester, Jason A. 02 October 2012 (has links)
No description available.
65

Friction stir spot welding of ultrathin sheets made of aluminium – magnesium alloy / Тачкасто заваривање трењем са мешањем ултратанких лимова од легуре алуминијума и магнезијума / Tačkasto zavarivanje trenjem sa mešanjem ultratankih limova od legure aluminijuma i magnezijuma

Labus Zlatanović Danka 17 September 2020 (has links)
<p>Within the framework of presented PhD, friction stir spot welding (FSSW) of<br />multiple ultrathin sheets of AA 5754 &ndash; H111 (AlMg3) alloy 0.3 mm thick, was<br />studied. The influence of tool geometry and process parameters such as rotational<br />speed and axial load have been analysed using numerous techniques. It has been<br />understood that during the welding at low rotational speeds weld zone undergoes<br />strain hardening, while at high rotational speeds weld zone undergoes thermal<br />softening. It was observed that during FSSW at low rotational speeds a complex<br />layer at weld interface is present, which causes delamination when welded samples<br />are subjected to load.</p> / <p>У оквиру ове докторске дисертације испитивано је тачкасто заваривање трењем са мешањем ултратанких лимова дебљине 0.3 mm од легуре АА 5754 &ndash; H111 (AlMg3). Утицај геометрије алата и параметара као што су угаона брзина и аксијално оптерећење су детаљно анализирани уз помоћ бројних техника. Установљено је да приликом заваривања ниским угаоним брзинама долази до деформационог ојачавања, док на високим угаоним брзинама долази до термичког омекшавања зоне завара. Код узорка завареног са најмањим бројем обртаја долази до формирања комплексног слоја на међуконтактној површини који изазива деламинацију приликом испитивања механичких особина.</p> / <p>U okviru ove doktorske disertacije ispitivano je tačkasto zavarivanje trenjem sa mešanjem ultratankih limova debljine 0.3 mm od legure AA 5754 &ndash; H111 (AlMg3). Uticaj geometrije alata i parametara kao što su ugaona brzina i aksijalno opterećenje su detaljno analizirani uz pomoć brojnih tehnika. Ustanovljeno je da prilikom zavarivanja niskim ugaonim brzinama dolazi do deformacionog ojačavanja, dok na visokim ugaonim brzinama dolazi do termičkog omekšavanja zone zavara. Kod uzorka zavarenog sa najmanjim brojem obrtaja dolazi do formiranja kompleksnog sloja na međukontaktnoj površini koji izaziva delaminaciju prilikom ispitivanja mehaničkih osobina.</p>
66

Μελέτη αλληλεπιδράσεων ιόντων Cu2+ με συμπολυμερή του ακρυλικού οξέος σε υδατικό διάλυμα / Study of the interactions between Cu2 + ion with acrylic acid copolymers in aqueous media

Τσοπελάκης, Φίλιππος 02 April 2014 (has links)
Στην εργασία αυτή προχωρήσαμε στη μελέτη της αλληλεπίδρασης των ιόντων δισθενούς χαλκού, Cu2+ με στατιστικά συμπολυμερή P(ANa-co-SSNa) του ακρυλικού οξέος, (ANa) με το στυρενοσουλφονικό οξύ (SSNa). Συντέθηκαν τα συμπολυμερή P(ANa50-co-SSNa) και P(AΝa80-co-SSNa) που περιέχουν 50 mol% και 80 mol% ακρυλικού οξέος αντίστοιχα. Τα συμπολυμερή αυτά χαρακτηρίστηκαν με φασματοσκοπία πυρηνικού μαγνητικού συντονισμού 1H NMR. Προχωρήσαμε στην φυσικοχημική μελέτη της αλληλεπίδρασης ιόντων δισθενούς χαλκού, Cu2+, με τα συμπολυμερή P(ANa50-co-SSNa) και P(AΝa80-co-SSNa) χρησιμοποιώντας διάφορες τεχνικές όπως η θολομετρία, η ιξωδομετρία και η φασματοσκοπία UV-vis. Τα πειράματα πραγματοποιήθηκαν σε υδατικά διαλύματα, στα οποία χρησιμοποιήθηκε ως διαλύτης τρισαπιονισμένο νερό, H2O-3D. Για λόγους σύγκρισης μελετήθηκαν επίσης τα αντίστοιχα ομοπολυμερή των μονομερών που αποτελούν τα συμπολυμερή P(ANa-co-SSNa). Έτσι, πραγματοποιήθηκε φυσικοχημική μελέτη της αλληλεπίδρασης των ιόντων Cu2+ με το πολυ(ακρυλικό νάτριο), PANa, και το πολυ(στυρενοσουλφονικό νάτριο), PSSNa, αντίστοιχα. Από την ιξωδομετρική μελέτη προέκυψε πως η εισαγωγή ιόντων χαλκού Cu2+ σε υδατικό διάλυμα πολυμερούς οδηγεί στην μείωση του ανηγμένου ιξώδους. Μάλιστα η μείωση αυτή είναι πιο δραστική καθώς αυξανεται η συγκέντρωση ιόντων Cu2+ στο διάλυμα. Αυτή η συμπεριφορά αποτελεί ένδειξη της συμπλοκοποίησης των ιόντων χαλκού, Cu2+, με τις ομάδες καρβοξυλίων του ακρυλικού οξέος (ΑΑ). Διαπιστώθηκε πως στα συμπολυμερή P(ANa-co-SSNa) τα Cu2+ συμπλοκοποιούνται με τα καρβοξύλια του ακρυλικού οξέος σε αναλογία ιόντων χαλκού προς ομάδες καρβοξυλίων ίση με 1:2. Όσον αφορά στην μελέτη με UV-vis, ενώ στην περίπτωση του ομοπολυμερούς PSSNa δεν υπάρχει κάποια ιδιαίτερη αλληλεπίδραση τύπου συμπλόκου ένταξης μεταξύ του πολυμερούς και των ιόντων του Cu2+, στην περίπτωση του συμπολυμερούς Ρ(ΑNa50-co-SSNa), παρατηρήθηκε μετατόπιση του σήματος των ιόντων Cu2+ (από τα 800 στα 745 nm) παρουσία του συμπολυμερούς. Αυτό είναι χαρακτηριστικό του σχηματισμού συμπλόκου ένταξης μεταξύ των ιόντων του Cu2+ και των ομάδων COO- του συμπολυμερούς. / In the present work we studied the interaction of bivalent copper ions Cu2+ with random copolymers P(ANa-co-SSNa) of acrylic acid (ANa) and styrenesulfonic acid (SSNa). Two copolymers, P(ANa50-co-SSNa) and P(AΝa80-co-SSNa) with 50 mol% and 80 mol% in acrylic acid, respectively, were synthesized and characterized by neutron magnetic resonance spectroscopy, 1H NMR. We proceeded in the physicochemical study of the interaction of bivalent copper ions, Cu2+, with P(ANa50-co-SSNa) and P(AΝa80-co-SSNa) copolymers using techniques like turbidimetry, viscometry and UV-vis spectroscopy. The experiments were performed in aqueous media using 3D water, H2O-3D. For reasons of comparison the respective homopolymers of sodium polyacrylate, PANa, and poly(styrene sulfonate), PSSNa, were also studied. From viscometry it was found that the introduction of copper ions in the polymer aqueous solutions leads to the decrease of the reduced viscosity. Moreover, this decrease is more pronounced as the concentration of Cu2+ increases in the solution. This behavior is indicative of the complexation between Cu2+ with the carboxylate groups of acrylic acid (ΑΑ). In the P(ANa-co-SSNa)/Cu2+ system, it was found that complexation occurs when the ratio of copper ions to carboxylates is equal to 1:2. UV-vis spectroscopy showed that, while in the case of PSSNa homopolymer there is not strong interaction with Cu2+, in the case of the Ρ(ΑNa50-co-SSNa) copolymer, the introduction of the polymer lead to a shift of the maximum absorbance of Cu2+ (from 800 to 745 nm). This was due to the complexation of Cu2+ with the COO- groups of the copolymer.
67

Identification of deformation mechanisms during bi-axial straining of superplastic AA5083 material

Fowler, Rebecca M. 06 1900 (has links)
Approved for public release, distribution is unlimited / This study evaluated dome test samples of a superplastic AA5083 aluminum alloy deformed at nominally constant strain rates under biaxial strain conditions. Dome test samples resulted from gas-pressure forming of sheet material; for this study, samples were deformed at strain rates corresponding either to grain boundary sliding or dislocation creep control of deformation. Orientation Imaging Microscopy was utilized to determine texture development, grain size and grain-to-grain misorientation angle distributions for locations located along a line of latitude of the dome samples. The goal was to identify the location of the transition from grain boundary sliding to dislocation creep. Grain boundary sliding, which dominates at lower strain rates, can be recognized by a randomized texture and a higher concentration of high disorientation angles. Dislocation creep, which dominates at higher strain rates, is characterized by fiber texture formation and development of a peak at lower angles in the grain-to-grain misorientation angle distribution. / Ensign, United States Navy
68

Estudo da evolução microestrutural no processo de extrusão de tubo da liga AA6351. / Study of the microstructure evolution of an AA6351 alloy extruded tube.

Jinan, Wei Tsu 12 March 2019 (has links)
A liga de alumínio AA 6351 é uma liga endurecível por precipitação coerente do sistema Al-Si-Mg, contendo adicionalmente Mn e Fe. Neste trabalho foi realizada a caracterização microestrutural durante o processamento de um tubo extrudado de parede grossa da liga AA 6351. Foram utilizadas várias técnicas complementares de caracterização microestrutural, tais como microscopia óptica de luz polarizada, microscopia eletrônica de varredura eletrônica (MEV), espectroscopia de raios X por dispersão de energia (EDS), difração de elétrons retroespalhados (EBSD), medidas de dureza e de condutividade elétrica. Foram analisadas as principais características dos grãos e precipitados presentes. Após solidificação, foi constatada a presença de uma distribuição relativamente homogênea de grãos com diâmetro médio de aproximadamente 100 ?m e de uma fase intermetálica com morfologia alongada e rica em Al, Fe, Mn e Si. Durante a extrusão, o tamanho de grão inicial foi reduzido para cerca de um quinto do diâmetro inicial e a fase alongada, provavelmente ?-Al(FeMn)Si, foi fraturada e redistribuída e as partículas resultantes da fragmentação foram alinhadas na direção de extrusão. Foi detectada e analisada uma zona periférica de grãos grosseiros nas proximidades das superfícies externa e interna do tubo. Tratamentos térmicos complementares realizados na faixa de 400 a 550ºC em amostras retiradas do tubo na condição T6 e medidas de condutividade elétrica revelaram que a dissolução de partículas associada à queda de condutividade elétrica tem início por volta de 440ºC. / The aluminum alloy AA 6351 is a precipitation hardening alloy of the Al-Mg-Si system, additionally containing Mn and Fe. In this work the microstructural characterization during processing of a thick wall extruded tube of the AA 6351 was carried out. Several complementary techniques of microstructural characterization were used, such as polarized light optical microscopy, electronic scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), backscattered electron diffraction (EBSD), hardness and electrical conductivity measurements. The main characteristics of the grains and precipitates were analyzed. After solidification, the presence of a relatively homogeneous grain distribution with an average diameter of approximately 100 ?m and of an intermetallic phase with elongated morphology rich in Al, Fe, Mn and Si was observed. During extrusion, the initial grain size was reduced to about one-fifth of the initial diameter and the elongated phase, probably ?-Al (FeMn) Si, was fractured and redistributed and the resulting particles of the fragmentation were aligned in the extrusion direction. A peripheral coarse grain zone was detected and analyzed in the vicinity of the outer and inner surfaces of the tube. Complementary thermal treatments performed in the range of 400 to 550ºC in samples taken from the tube in the T6 condition and electrical conductivity measurements revealed that the precipitate particles dissolution associated with the electrical conductivity drop starts at around 440ºC.
69

Rätten till gränsöverskridande förlustutjämning ur ett svenskt perspektiv – En realitet eller ett spel för galleriet? : En juridisk analys med fokus på Regeringsrättens tolkning av de svenska koncernbidragsreglernas förenlighet med EG-rätten / The right to cross-border loss relief from a Swedish perspective – A reality or a play to the gallery? : A legal analysis with focus on the Supreme Administrative Court’s interpretation of the Swedish group contribution rules’ compatibility with EC law

Lindahl, Emelie January 2009 (has links)
<p>The Swedish group contribution rules do not include a right to deduction for cross-border group contributions unless the receiving company is taxable in Sweden. There has been much discussion regarding whether the rules are compatible with EC law. On 11 March 2009 the Swedish Supreme Administrative Court ruled ten cases concerning the right to deduction for cross-border group contributions. In three of these judgments deduction for a group contribution from a Swedish parent company to a foreign subsidiary within the EEA was allowed, despite that the subsidiary was not taxable in Sweden. The main purpose of this master thesis is to analyse whether the interpretation of the Supreme Administrative Court concerning the right to deduction for cross-border group contributions is compatible with EC law. In order to achieve this purpose an extensive analysis of EC case law concerning cross-border loss relief as well as of the judgements of the Supreme Administrative Court is undertaken.</p><p>The results of the thesis show that the interpretation of the case law of the European Court of Justice concerning cross-border loss relief is far from obvious. Taken together the <em>Marks & Spencer</em> and <em>Oy AA</em> cases imply that deduction for cross-border group contributions to a parent company can be refused, irrespective of the existence of final losses. However EC law seems to include a right to deduction for cross-border group contributions to a subsidiary, provided that the subsidiary has final losses. A final loss exists if the subsidiary has exhausted all possibilities of having the losses taken into account in its state of residence. The Supreme Administrative Court allowed deduction for cross-border group contributions from a Swedish parent company to a foreign subsidiary within the EEA if the subsidiary was to be liquidated. Despite that deduction was allowed, some uncertainties remain regarding how this should be achieved in practice. On the contrary, deduction was refused for cross-border group contributions to both parent companies and between subsidiaries. With respect to <em>Marks & Spencer</em> and <em>Oy AA</em> the interpretation of the Supreme Administrative Court so far seems compatible with EC law.</p><p>Regarding the cases in which deduction for cross-border group contributions to foreign subsidiaries within the EEA was refused because the losses had been lost after some time according to internal tax rules in the subsidiary’s state of residence, it could however be questioned if this interpretation is compatible with EC law. Such losses should be considered final in the sense of Marks & Spencer. In the light of EC case law as well as the case law of the Supreme Administrative Court at least the wording of the group contribution rules should be considered contrary to EC law. Even if the application of the rules in practice should turn out to be fully compatible with EC law, it is nonetheless unacceptable from a perspective of rule of law and predictability to leave the Swedish group contribution rules in their present wording.</p> / <p>De svenska koncernbidragsreglerna innefattar inte någon rätt till avdrag för gränsöverskridande koncernbidrag om det mottagande bolaget inte är skattskyldigt i Sverige. Diskussion har förts kring reglernas förenlighet med EG-rätten. Den 11 mars 2009 avgjorde Regeringsrätten tio mål beträffande rätten till avdrag för gränsöverskridande koncernbidrag (fortsättningsvis koncernbidragsmålen). I tre av dessa mål medgavs avdrag för koncernbidrag från svenskt moderbolag till utländskt dotterbolag inom EES, trots att dotterbolaget inte var skattskyldigt i Sverige. Det huvudsakliga syftet med denna uppsats är att utifrån koncernbidragsmålen analysera huruvida Regeringsrättens tolkning beträffande rätten till avdrag för gränsöverskridande koncernbidrag är förenlig med EG-rätten. För att uppfylla syftet företas en omfattande analys av såväl EG-rättslig praxis beträffande gränsöverskridande förlustutjämning som Regeringsrättens domar i koncernbidragsmålen.</p><p>Uppsatsens resultat visar att tolkningen av EG-domstolen praxis beträffande gränsöver-skridande förlustutjämning inte på något sätt är självklar. Sammantaget tyder dock domarna i målen Marks & Spencer och Oy AA på att avdrag inte måste medges för gränsöverskridande koncernbidrag till moderbolag. Däremot synes EG-rätten inkludera en rätt till avdrag för gränsöverskridande koncernbidrag till dotterbolag, förutsatt att dotterbolaget har slutliga förluster. En slutlig förlust föreligger om dotterbolaget uttömt möjligheterna att utnyttja förlusten i hemviststaten. Regeringsrätten medgav i koncernbidragsmålen avdrag för gränsöverskridande koncernbidrag från svenskt moderbolag till ett utländskt dotterbolag inom EES om dotterbolaget skulle likvideras. Trots att avdrag medgavs i denna situation kvarstår vissa oklarheter med avseende på hur detta ska uppnås i praktiken. Däremot vägrades avdrag för gränsöverskridande koncernbidrag till såväl moder- som systerbolag. Mot bakgrund av Marks & Spencer och Oy AA synes Regeringsrättens tolkning så långt som huvudregel vara förenlig med EG-rätten.</p><p>Beträffande de mål där avdrag för gränsöverskridande koncernbidrag till dotterbolag vägrades då förlusterna i dotterbolaget hade gått förlorade efter viss tid enligt interna skatteregler i dotterbolagets hemviststat, kan emellertid ifrågasättas om denna tolkning är förenlig med EG-rätten. Sådana förluster bör nämligen vara att betrakta som slutliga i den meningen som avsågs i Marks & Spencer. Mot bakgrund av både EG-domstolens praxis och Regeringsrättens domar i koncernbidragsmålen får anses att åtminstone koncernbidragsreglernas ordalydelse står i strid med EG-rätten. Även om tillämpningen av koncernbidragsreglerna till fullo skulle visa sig vara förenlig med EG-rätten, är det oacceptabelt ur ett rättssäkerhets- och förutsebarhetsperspektiv att utan andra åtgärder lämna de svenska koncernbidragsreglerna i deras nuvarande utformning.</p>
70

In search of an appropriate leadership ethos : a survey of selected publications that shaped the Black Theology movement

Ndalamba, Ken Kalala January 2010 (has links)
<p>The understanding and practice of leadership in Sub-Saharan Africa, in all spheres, is at the heart beat of this work. Questions and concerns over the quality of leadership in most countries in this particular region are reasons which have led to revisit and investigate the formative training of the current cohort of African leadership with a special focus on the ethical aspect of leadership. It is an assumption, in this thesis, that the contemporary cohort of African leadership received their formative training especially in the 1960s and 1970s and that they were deeply influenced by the black consciousness movement and, in association with that, by the emergence of black theology. In this respect, this research project explores the notions of ethics and leadership with a view to determine ways in which an appropriate leadership ethos was portrayed and articulated in the writings of selected exponents of the black theology movement, namely ML King (Jr), Desmond Tutu and Allan Boesak. The purpose of this work is therefore mainly descriptive: to map discourse on a leadership ethos in the context especially of black theology.</p>

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