The R2PdSi3 (R = heavy rare earth) have been synthesized first in 1990 in the search for materials with unusual electronic properties. The availability of single crystals was the starting point for several investigations of the magneto-crystalline anisotropy, also in applied magnetic fields. The results of the observed properties in resistivity, magnetization and susceptibility lead to the summary that these compounds range from interesting to exotic and that their magnetic properties are low dimensional, spin-glass like and altogether “novel”. The focus of this thesis is the careful analysis of the magnetic properties and magnetic structures of single crystalline R2PdSi3 (R = Gd, Tb, Dy, Ho, Er, Tm). The investigation of macroscopic properties uses magnetization and ac-susceptibility measurements. Resulting from these investigations are magnetic phase diagrams. Neutron and resonant X-ray diffraction measurements elucidate the magnetic structure for the investigated compounds. The phase diagram of Tb2PdSi3 is the starting point of a detailed neutron diffraction study in applied magnetic fields up to 6.5 T and in the temperature range from 0.05 K to 100 K on this compound. Key to the understanding of the R2PdSi3 is the strong coupling of crystallographic structure to the magnetic properties. Thus the established framework of exchange interaction and magneto-crystalline anisotropy allows a collective description instead of a “novel” behavior. / Die R2PdSi3 (R = schwere seltene Erde) sind erstmals 1990, im Rahmen der Suche nach Materialien mit ungewöhnlichen elektronischen Eigenschaften, synthetisiert worden. Die Verfügbarkeit von Einkristallen war der Startpunkt für eine Vielzahl von Untersuchungen, auch in angelegten Magnetfeldern, der magneto-kristallinen Anisotropie. Das Ergebnis der untersuchten Eigenschaften Widerstand, Magnetisierung und Suszeptibilität führte zu dem Schluss, dass diese Verbindungen interessant bis exotisch und das ihre magnetischen Eigenschaften niedrig dimensional, spin-glas ähnlich und insgesamt “neuartig“ sind. Der Schwerpunkt dieser Dissertation ist die genaue Analyse der magnetischen Eigenschaften und Magnetischen Strukturen von einkristallinen R2PdSi3 (R = Gd, Tb, Dy, Ho, Er, Tm). Magnetisierungs- und Suszeptibilitäts-Messungen werden zur Untersuchung der makroskopischen Eigenschaften benutzt. Resultat dieser Untersuchungen sind magnetische Phasendiagramme. Neutronen und resonante Röntgendiffraktrometrie klären die magnetische Struktur der untersuchten Verbindungen auf. Das Phasendiagramm von Tb2PdSi3 ist der Startpunkt einer detaillierten Neutronendiffraktionsuntersuchung dieser Verbindung in Magnetfeldern bis 6.5 T und im Temperaturbereich von 0.05 K und 100 K. Der Schlüssel zum Verständnis der R2PdSi3 ist die starke Kopplung der kristallografischen Struktur und der magnetischen Eigenschaften. Dadurch erlaubt das etablierte System aus Austauschwechselwirkung und magneto-kristalliner Anisotropie eine gemeinsame Beschreibung anstatt „neuartigem“ Verhalten.

Title from PDF of title page. / Document formatted into pages; contains 64 pages. / Thesis (M.E.E.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: The ability of Mercuric Iodide (HgI2) to function as a highly efficient radiation detector at room temperature has generated great interest and has triggered further studies on this difficult material. This property is expected to enable significant enhancements to a far-ranging variety of applications and systems. HgI2 devices have shown superior performance at room temperature compared to elemental Si or Ge devices, which require to be cooled down to liquid nitrogen temperature when used as nuclear radiation detectors. While substantial studies have been conducted on single crystal HgI2, polycrystalline HgI2 remains a comparatively less studied form of this material. The primary use of HgI2 is as a direct radiation detector. It can also be used in applications with a scintillator intermediate to generate visible light from incident nuclear radiation. Hence its response to visible light can be used to study the electronic properties of HgI2 polycrystalline films. / ABSTRACT: The films are deposited on TEC-15 LOF glass with a Tin Oxide(Sn02) coating which acts as the growth surface. It also acts as the front contact with Palladium (Pd) being the back contact. Wire leads are attached to the palladium for electrical contact. The deposited films are circular in shape with a diameter of 2.5cm with thickness ranging from 50 to 600ìm. A maximum of 7 devices are contacted at various points on every film. For the measurements documented in this thesis, a tungsten-halogen lamp and an Oriel 1/4m grating monochromator are used as a light source. The incident flux on the sample is determined using a Si photodiode as reference. Device performance for both single crystal as well as polycrystalline films is documented. We have attempted to identify a set of optimum growth parameters using these measurements. / ABSTRACT: For a film to be considered favorably, not only should the individual devices show high quantum efficiencies and low dark currents, but the response of all devices on the same film should be uniform. A number of films are studied and the optimum film deposition conditions are commented upon. A powerful semiconductor device simulation tool, MEDICItm, is used to simulate the photoresponse of these films. The simulations are compared to the measurements and the transport and light absorption parameters of the polycrystalline films are determined. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.

Si complementary metal-oxide-semiconductor (CMOS) technology has been prospered through continuously scaling of its feature size. As scaling is approaching its physical limitations, new materials and device structures are expected. High electron mobility III-V materials are attractive as alternative channel materials for future post-Si CMOS applications due to their outstanding transport property. High-k dielectrics/metal gate stack was applied to reduced gate leakage current and thus lower the power dissipation. Combining their benefits, great efforts have been devoted to explore III-V/high-k/metal metal-oxide-semiconductor field-effect-transistors (MOSFETs). The main challenges for III-V MOSFETs include interface issues of high-k/III-V, source and drain contact, silicon integration and reliability. A comprehensive study on III-V MOSFETs has been presented here focusing on three areas: 1) III-V/high-k/metal gate stack: material and electrical properties of various high-k dielectrics on III-V substrates have been systematically examined; 2) device architecture: device structures from planar surface channel MOSFETs and buried channel quantum well FETs (QWFETs) to 3D gate-wrapped-around FETs (GWAFETs) and tunneling FETs (TFETs) have been designed and analyzed; 3) fabrication process: process flow has been set up and optimized to build scaled planar and 3D devices with feature size down to 40nm. Potential of high performances have been demonstrated using novel III-V/high-k devices. Effective channel mobility was significantly improved by applying buried channel QWFET structure. Short channel effect control for sub-100nm devices was enhanced by shrinking gate dielectrics, reducing channel thickness and moving from 2D planar to 3D GWAFET structure. InGaAs TFETs have also been developed for ultra-low power application. This research work demonstrates that III-V/high-k/metal MOSFETs with superior device performances are promising candidates for future ultimately scaled logic devices. / text

La présente thèse étudie le rôle de l'accent prosodique (accent de mot vs. accent de syntagme) lors du traitement auditif de paires minimales ambigües (mots composés vs. syntagmes) du chinois mandarin. Deux types de paires minimales ont été utilisés: 1) Mots composés avec un ton neutre (ex: dong3xi0 « chose ») vs. Syntagme avec un ton plein (ex: dong3xi1 « est et ouest ») qui se distinguent par la réalisation du ton sur la syllabe finale ; 2) Mots composés Verbe-Nom (VN) (ex: 'chaofan « riz frit ») vs. Syntagmes Verbe-Objet (VO) (ex: chao'fan « frire du riz ») se distinguant par la position de l'accent prosodique. Nos données comportementales et neurophysiologiques démontrent que : 1) la syllabe finale est plus longue et l'étendue de la F0 est plus large dans les VO que dans les VN, 2) la prosodie assiste le système de traitement pour anticiper la structure morphologique des séquences ambigües, et 3) un traitement hiérarchique « de droite-à-gauche » des informations prosodiques en complément d'un traitement séquentiel « de gauche-à-droite » prend place en chinois mandarin. Prises dans leur ensemble, nos données précisent la description fonctionnelle et structurale du modèle Prosody-Assisted-Processing (PAP) pour le chinois mandarin. / The present thesis investigates the role of prosodic stress (i.e. lexical versus phrasal stress) on the auditory processing of Mandarin Chinese ambiguous compound /phrase minimal pairs. Two types of compound/phrase minimal pairs were used: 1) Compound word with a neutral tone (e.g. dong3xi0 "thing") vs. phrase with a full tone (e.g. dong3xi1 "east and west") distinguished by the final syllable tone realization; 2) Verb-Noun (VN) compound word (e.g. 'chaofan "fried rice") and Verb-Object (VO) phrase (e.g. chao'fan "fry the rice") distinguished by the position of the prosodic stress. Combined behavioral and neurophysiological data demonstrate that 1) the final syllable was more lengthened and the F0 range was larger in VO than in VN, 2) prosodic structure does assist the processing system in anticipating morphological structure, and 3) a right-to-left hierarchical processing of prosodic information in addition to a sequential left-to-right one is involved during the processing of ambiguous spoken sequences in Mandarin Chinese. Taken together, our findings allowed us to precise the functional and structural description of the Prosody-Assisted-Processing (PAP) model for Mandarin Chinese.

Linguistic terms and all use cases were collected from Vincas Urbutis book “Word-building theory”. It was found 1464 different linguistic terms, which were used 4143 times. It was established, that almost 13 of all linguistic terms are descended from Lithuanian (373 terms or 25,5 % of all linguistic terms), 16 other language (216 terms or 14,8 % of all linguistic terms) and 23 of all linguistic terms are hybrids (875 or 59,8 % of all linguistic terms). For the most part of other language one-word terms are descended from classical – the Latin (104 terms or 40 % of all one-word terms) and the Greek (52 terms or 20 % of all one-word terms) – languages. It was found 13 terms or 5 % of all one-word terms, which are descended from the French language and 7 terms descended from other languages. 302 compound terms are Lithuanian (25,1 % of all compound terms). It was found 40 international compound terms (3,3 % of all compound terms). The biggest part of compound terms forms hybrids (71,6 % of all compound terms). From the respect of structure, terms are different – one-word (260 terms or 17,8 % of all terms) and compound (1204 terms or 82,2 % of all terms). The biggest part of one-word terms forms derivatives (150 terms or 57,7 % of all one-word terms), other part (110 terms or 42,3 % of all one-word terms) forms primary terms. The biggest part of linguistic terms are built with suffixes (114 terms or 43,8 % of all one-word terms). Mostly derivatives of suffixes are action names (4... [to full text]

The isolation and identification of the active constituents from an Allium sp. extract possessing antibacterial activity was undertaken. The plant material of interest was extracted, purified and screened for antibacterial activity against a Gram positive bacteria. Multiple trials were performed and the isolation was scaled-up repeatedly, overall three compounds potentially possess the observed activity. One compound was identified to yield the majority of activity, and a refined procedure for its purification was established. Initial characterization studies demonstrated the major isolate of interest is novel compared to other isolates from the Allium genus. A ruthenium-catalyzed homo Diels-Alder [2+2+2] cycloaddition between bicyclo[2.2.1]hepta-2,5-diene and alkynyl phosphonates was also studied. The observed reactivity was found to be dependent on the presence of the phosphonate moiety. The cycloaddition was compatible with a variety of aromatic and aliphatic substituted alkynyl phosphonates providing the corresponding phosphonate substituted deltacyclenes in low to good yields (up to 88%).

Baigiamajame bakalauro darbe išanalizuoti 1077 edukologijos terminai, išrinkti iš L. Jovaišos Enciklopedinio edukologijos žodyno (2007). Jų sandara, kilmė, daryba ir kirčiavimas iki šiol plačiau nenagrinėti. Edukologijos terminai sandaros atžvilgiu suskirstyti į vienažodžius ir sudėtinius (dvižodžius, trižodžius ir keturžodžius) terminus, nustatytos jų kirčiuotės. Dauguma edukologijos terminų yra vienažodžiai terminai – 655 (60,8 proc.), sudėtinių terminų rasta 422 (39,2 proc.). Daugiau nei pusė vienažodžių edukologijos terminų yra lietuviški žodžiai – 378 (57,7 proc.). Net 592 vienažodžiai terminai (90,4 proc.) yra pirmosios ir antrosios kirčiuočių – atitinkamai 363 ir 229. Trečiosios kirčiuotės rasti 35, o ketvirtosios – 26 terminai. Lietuviški vienažodžiai pirmosios kirčiuotės edukologijos terminai dažniausiai turi priesagą -imas (60), reiškiančią veiksmų pavadinimus. Tarp antrosios kirčiuotės lietuviškų edukologijos terminų daugiausia turinčių priesagas -umas (56), kuri reiškia ypatybių pavadinimus, ir -imas (47), reiškiančią įvairius veiksmus. Iš tarptautinių pirmosios kirčiuotės vienažodžių edukologijos terminų daugiausia yra su baigmeniu -ija (74), antrosios kirčiuotės – su baigmeniu -izmas (22). Iš sudėtinių edukologijos terminų daugiausia yra dvižodžių terminų – 355 (84,1 proc.). Tarp jų vyrauja terminai su prepoziciškai prijungtais dėmenimis. / The bachelor thesis analyzes 1077 terms of education which were selected from Encyclopaedic Dictionary of Education (Enciklopedinis edukologijos žodynas) by L. Jovaiša (2007). Their structure, origin, formation and accentuation have not been analyzed in detail yet. In regard to the structure, terms of education are divided into one-word and compound (consisting of two, three and four words) terms. Their accentuation classes have been determined. Most terms of education are one-word terms – 655 (60,8%), 422 (39,2%) compound terms have been found. More than a half of one-word terms of education are Lithuanian words – 378 (57,7%). 592 (90,4%) one-word terms, respectively 363 and 229 ones, are of the first and second accentuation classes. There have been found 35 terms of the third accentuation class and 26 ones – of the fourth accentuation class. Lithuanian one-word terms of education belonging to the first accentuation class often have the suffix -imas (60) which expresses the names of actions. Lithuanian terms of education belonging to the second accentuation class generally have the suffixes -umas (56) (expresses the names of characteristics) and -imas (47) (expresses various actions). International one-word terms of education belonging to the first accentuation class have the ending -ija (74), while the terms of the second accentuation class have the ending -izmas (22). A vast majority of compound terms of education are two-word terms – 355 (84,1%). Terms with... [to full text]

In this study, we have synthesized two families of new carbohydrate-based amphiphilic derivatives: a series of alkyl glucoside ethers varying in terms of chain length and position on the sugar, and a series of glucosteroids varying in terms of alkyl spacer and, for the disutibstuted systems, in terms of alkyl side chain length. By the means of analytical methods, such as NMR spectroscopy, mass spectroscopy and elementary analysis, the structure of all the compounds was carefully established, as well as their purity. Their liquid crystalline behaviors were studied by the means of transmission light microscopy and differential scanning calorimetry. The two families of compounds which have been studied illustrate how much the behavior can be essentially related to polar interactions (H-bonding), therefore to the sugar moiety, for the ether series, or to hydrophobic interactions (lipid-lipid) in the glucosteroid series. In this latter series, preference for either steroid-stroid or steroid alkyl packing appears as an insight in understanding the behavior of complex lipids, showing potentially more than one conformational structure with important consequences on the supramolecular level, therefore to their potential biological role. This could be regarded as "lipid denaturation" by analogy to the protein denaturation. Also, when we see that compounds like the glycosteroids having an long chain ester -CAG, BbGL-I, are found to exist in Nature, and how much glycolipid-cholesterol interactions were recently shown to be critical in some biological processes, it is hoped that our observations can provide a new vision angle for the study of complex lipids and glycolipids. As a start to develop new probes targeting the "lipid raft" microdomain in membranes, we also explored a sequence towards carbohydrate laurdan hybrids. Further development of this strategy and evaluation of the biological properties is programmed within new collaborative projects.

Heterocyclic’s and their fused-ring derivatives have been of interest for their use in electronic materials due to their ease of production, synthetic versatility, and low cost compared to traditional inorganic materials like silicon. Pyridazines have been found to be useful in catalysis gas storage, polymeric sensors and biological mimetics. When a transition-metal is fused into a synthesized pyridazine, unique properties such as conductivity and optics are allowed. In this work, synthesized pyridazine complexes will be analyzed by mass spectroscopy, elemental analysis, nuclear magnetic resonance, imaging, x-ray crystallography, and infrared spectroscopy. We are interested in synthesizing organometallic pyridazines and manganese pyridazyl complex for polymer research. Off-metal synthesis and characterization of manganese pyridazyl complex required three intermediate steps. The research focuses on the synthesis and characterization of various manganese pyridazyl complexes.

Binding of volatile flavour compounds to plant proteins is known to be an issue, particularly for developers of flavoured gluten-free snacks made with pea protein. This project used a model system to describe the effects of extraction and heat on the binding of hexanal (Hex), hexyl acetate (HxAc) and 2-octanone (2-Oct) to pea protein isolate and to evaluate any resulting change in protein functionality.