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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.
1

Interdiffusion effect on the strained films La0.8Ba0.2MnO3/SrTio3 by off-axis sputtering

Hsu, Hsin-Kuo 08 September 2006 (has links)
When Colossal Magnetoresistance films are grown on lattice mismatched substrates, the strain on the film/substrate interface induces a strong strain that altered the intrinsic properties on transport and magnetic measurements. The transition temperatures of La0.7Ca0.3MnO3(LCMO) and La0.7Sa0.3MnO3(LSMO) thin films are lowered by both tensile and compress strains, while La0.8Ba0.2MnO3(LBMO) films may be increased or decreased dependent on the type of strains. When La0.8Ba0.2MnO3(LBMO) films were grown on SrTiO3 (STO) substrate by a standard off-axis RF sputtering technique, the compressed strain enhanced the transition temperatures. When La0.8Ba0.2MnO3(LBMO) films were further annealed at higher temperature, the transition temperature was increased up to temperature that was never been achieved, and this phenomena can not be explained solely by the strain effect. In this study, Secondary ion mass spectroscopy and X-ray reciprocal mapping were used to investigate the possible cause of the extra enhancement in transition temperatures. It is found that under a fixed annealing condition the substrate element, Sr, diffuses partially into the film that separated the films into the top layer and the bottom layer acting as La1-x(SryBa1-y)xMnO3 with higher transition temperature. The TC enhancement can be attributed to the combination of the strain and interdiffusion effects.
2

Growth mechanical of (La,A)MnO3,A=Ca,Sr And Film thickness effect of Colossal magnetoresistance(CMR)

Hsu, Ching-Chung 13 July 2001 (has links)
Abstract There has been much interest in colossal magnetoresistance in doped maganite peroviskite meterials.(La,A)MnO3 thin film have been fabricated by off-axis RF magnetron sputtering techhique. The Growth mechanical of (La,A)MnO3 A=Ca,Sr in Different growth temperatures on substrate and different annealing temperatures reveals the observably different results on its structure and electrical transport properties. Due to the lattice mismatch between substrates and bulk,strain has been a important factors of magnetic resistance and electrical properties. Different thickness of La0.67Ca0.33MnO3 thin film were grown on (001)SrTiO3 and(001)MgO substrates at growth temperature 750 degree C ,it has shown systematic variations to film thickness in magnetic and electrical transport properties.
3

The Growth of N-type La0.7Ce0.3MnO3 Thin Films and Relative Properties

Tsai, Ming-kung 15 August 2008 (has links)
Hole-doped colossal magnetoresistance (CMR) materials La1-xAxMnO3 (A=alkaline metal, 0≤x≤1) has been extensively studied because of its colossal magnetoresistance (CMR) characteristic in a magnetic field. Recently, many suspicious electron-doped CMR materials have been reported. However, none of these ¡§pure phases¡¨ were supported directly by experiment evidences, instead, various impurity phases were found. The La0.7Ce0.3MnO3 (LCeMO) target forming by a solid state reaction method, after analyzing its crystal structure and electric transport properties, is also found to be decomposed into CeO2 impurity and a La deficient La1-dMnO3 phases. This is believed to because the doped Ce4+ ions transforming the Mn3+ ions to Mn2+ whose larger ionic radius (aMn2+ =0.83Å), comparing to that of Mn3+(0.645Å), makes the MnO6 structure instable. Therefore, instead of forming an instable phase, the sample prefers to decompose into different phases. In this study, we propose to grow LCeMO films on an in-plane-enlarged STO bottom layer which was grown under a tensile strain on MgO (c=4.216Å) substrate. We found that all as grown films exhibits insulating behavior. Nevertheless, the samples after a rapid thermal annealing process can easily decompose the films into multiphase.
4

The Surface Modification of SrTiO3(100) and Physical Properties Research on CMR Thin Films

Hung, Chan-yu 22 August 2008 (has links)
The high magnetoresistance is one of the most important properties that led the colossal magnetoresistance (CMR) materials been kept attention, however, because of the low phase transition temperature (Tp) and Curie temperature (TC) limits the application of the materials. The Tp could be influenced by many factors, as for the R1-xAxMnO3(R=rare earth element, A=alkaline metal, 0¡Õx¡Õ1) CMR materials, the selections of elements on R, A, and the ratio of x would make the difference. Besides these factors, when the film was grown on a substrate, the strain effect initiated at the substrate/film interface plays an essential role on the change of Tp and other physic properties. In other hand, the Sr element, existed in the SrTiO3(100) substrate, may also diffuse into the thin films during growth and alter the composition of the film and change its physic properties. In this thesis, we mainly focused on the modifying of the surface of substrates to prevent the diffusion problems. A wet chemical method was applied to modify the top layer of substrates such that the surface layer of the substrate is consisted of Ti-O layer only. By varying the high temperature annealing and etching processes, an optima processing condition was established.
5

Problemlösning i praktiken : En observationsstudie med läromedelsanalys

Åström, Julia January 2022 (has links)
I den svenska matematikundervisningen har problemlösning fått en allt större roll genom åren. Idag finns formuleringar kring problemlösning med i samtliga kursplaner för matematik i gymnasieskolan, där det framgår att problemlösning ska synas i matematikundervisningen både som mål och medel. Forskningsfältet kring problemlösning är utbrett över hela världen och över decennier, och problemlösningsförmågan är något som idag efterfrågas på den internationella arbetsmarknaden. I den här studien har målet varit att försöka få en inblick i hur problemlösning sker i klassrummen, i vilken utsträckning samt hur läromedlen påverkar nivån av problemlösning. Observationer har genomförts i fyra olika klassrum och de läromedel som använts under lektionstillfällena har analyserats. Resultaten visar på att problemlösning inte skett i någon större uträckning, att de läromedel som använts till stor del innehåller proceduruppgifter samt att elever och lärares muntliga resonemang verkar vara de situationer då problemlösning oftast sker.
6

Convolutional neural networks using cardiac magnetic resonance for early diagnosis and risk stratification of cardiac amyloidosis

Cockrum, Joshua W. January 2022 (has links)
No description available.
7

Odpovědnost dopravce v mezinárodní přepravě zboží se zřetelem na silniční přepravu / Liability of carrier in international carriage of goods with respect to road carriage

Pravda, Jan January 2018 (has links)
Liability of the carrier in international carriage of goods with respect to road carriage Abstract The content of this thesis is carrier's liability in international carriage of goods focused on carriage of goods by road, which is one of the crucial branches of carriage for landlocked states. The introducing part explains basic terms which are common in international carriage, defines subjects participating in the carriage and its possible plurality. Moreover, the thesis presents individual types of carriage and a specific chapter is dedicated to cabotage. The second part of the thesis describes both international and national legislation of carriage contract. This part includes the relation between these two from the private international law point of view. Different types of contracts are also mentioned as another possibility of carriage. Common interpretation is enclosed in the third part with issues of liability from legal doctrine perspective. This part also analyses particular presumptions in generating of liability and differences among strict liability and liability for fault. The liability of the carrier as a main point of this thesis is expanded in the adjacent passage. Fundamental types of carrier's liability for loss or damage of goods as well as for any delay in delivery are found in the fourth...
8

Vybrané problémy provozu dopravní firmy MKD / Various problems of running an international haulage

Kadavá, Eva January 2010 (has links)
Transport sector as a whole records growing trend, whereas road transport has recorded the biggest growth of transported goods. An increase in international trade brings more opportunities for firms involved in the haulage industry. The aim of this thesis is to show the basic requirements in order to set up the haulage and forwarding business. I will mention various factors, that influence the transport market. In other chapters I will analyze laws and treaties, which every haulage company has to adhere to. The last chapter is devoted to problems of financing truck fleet. In the end there is a summary of ways on how to tackle and reduce non-payment by clients.
9

Právní úprava přepravy věci / The legal regulation on the carriage of goods

Slušný, Vladimír January 2018 (has links)
The present thesis deals with the legal regulation on the carriage of goods. This issue occupies an important role in everyday economic reality. Legal regulation in this field is highly stratified among legal regulations concerning private law, international agreements and partly among legal regulations concerning public law. This thesis mainly covers the regulation contained in the Czech Civil Code and in international conventions. In addition to the introduction and conclusion, this thesis is divided into five chapters, which are further divided, with the exception of the first chapter, into subchapters. The first chapter, which focuses on historical development and mainly on Roman law, is followed by chapters dealing with particular types of contracts which can be the legal cause for the carriage of goods. These include the following: contract for the carriage of goods, forwarding contract and contract for the operation of a means of transport. Firstly, these contracts are characterized and then the elements of such contracts are described, as well as the duties and rights of the contracting parties and questions regarding compensation for damage. The thesis also points out the interpretative problems that occur in the regulation of these contracts. The differences between these types of...
10

Úloha nákladního listu CMR v přepravních službách / The Role of Waybill CMR in Transportation Services

Vacek, Tomáš January 2011 (has links)
The first part of this thesis is devoted to the General Convention of CMR, CMR consignment note, obligatory data which are necessary to write in and to the parties acting on the transport market. The second part will focus on the carrier's liability as same as liability of other parties, insurance carrier's liability for loss, damage or destruction of the consignment, lapse, complaint and insurance. This issue will be demonstrated and will discuss with the court decisions. The next section will be described and analyzed electronic CMR. This section tries to evaluate the positives and negatives of its use in practice and its future. In particular, this part will be engaged in research which has implemented among members by the International Road Transport Union.

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