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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.
141

A Study of Sulfide Conversion Process of CuInSe2

Liu, Chun-Ping 25 August 2006 (has links)
Thin films of CuInSe2 can be completely converted into CuInS2 after annealing in elemental sulfur vapor. In this thesis, the sulfide conversion process was done in an MBE chamber and the film was exposed to a heated sulfur source. Our experiments showed that complete conversion of a 1.0 £gm-thick CuInSe2 film into CuInS2 was achieved when the film was annealed in a sulfur beam flux of 4.5x1016 atoms/cm2-sec at 450¢J for 5 minutes. This is the shortest conversion time ever reported for the same annealing temperature. The speed of conversion process depended on sulfur vapor flux, film crystallinity, and original film composition. Among them, the film composition was the most important factor. The presence of Cu2Se phase in Cu-rich CuInSe2 film enhances the sulfide conversion process and confirmed by KCN etching of a Cu-rich sample. The role of Cu2Se phase in sulfide conversion was investigated. The sulfide conversion mechanism also presented in this work.
142

An aid to convert spreadsheets to higher quality presentations

Olajide, Wasiu Olaniyi 29 August 2005 (has links)
A table is often the preferred medium for presenting quantative information. In some cases the presentation of quantative information can be presented as textual data or graphics at a loss of precision and clarity. The subject of this thesis is to aid the extraction and production of quality tables from a common means of preparing data in tabular form, the spreadsheet. Spreadsheet processors are in common use. Many tables are prepared by a range of users from the na??ıve users to experts in graphic arts. Spreadsheet data is also produced in automatic form from applications. We will review the specification of tabular data, presentation formats, and the systems and their associated formats for storing and interchange of data. The goal of this research is the specification and development of a system to convert common spreadsheet data to a markup language that will allow for presentation of the data at a higher level of typographic excellence. The desired characteristics of this system will include 1. Robust importing of data from an array of commercial and open spreadsheet processors 2. Formatting decisions of the output specified by the user rather than taken from the spreadsheet 3. Development or identification of a canonical form that is robust, does not lose data, and allows for repeated automatic application of styles 4. Development of a program to convert this canonical form into a markup system.
143

Genetic diversity and combining ability among sorghum conversion lines

Mateo Moncada, Rafael Arturo 25 April 2007 (has links)
Sorghum (Sorghum bicolor [L] Moench) was first introduced to the United States in the 1800s. These introductions consisted of tropical varieties with a short day photoperiod response that limited their use in temperate hybrid breeding programs. Commercial exploitation of F1 hybrids in grain sorghum started by the mid 1950s with the use of cytoplasmic male sterility system CMS (A1). Even though other CMS are available, most sorghum hybrid seed production still relies on the A1 system. Genetic gain in most agronomic crop species is limited by several factors. In the specific case of sorghum, the uniform use of the CMS (A1) system and the recent introduction of sorghum to the United States have resulted in a reduction of its genetic base. In order to create enough genetic variability, plant breeders might utilize exotic non adapted material, exotic adapted material or existing elite material as a source of new alleles that will protect and improve genetic gain through selection. This study provides an estimate of the genetic diversity existing in a set of sorghum conversion lines. The objectives of this study were: (1) to estimate the genetic diversity present among a set of 16 sorghum conversion lines; (2) to classify this set of lines based on genetic similarities estimated using AFLP markers and (3) to estimate heterosis, general and specific combining ability for grain yield among the set of conversion lines. Genetic diversity was present in the set of conversion lines evaluated. For the lines included only in this study, Caudatum was the most homogenous race (average GS = 0.69), and this race was closely related to the Durra race (Average GS = 0.66). Two other homogenous races were Bicolor and Kafir with average GS of 0.67. Highest GCA effects were obtained from the Kafir and Caudatum races. Good heterotic responses were obtained from DurraKafir races and CaudatumKafir races. Estimation of SCA, MPH and BPH identified specific crosses that were numerically superior than those of the checks. The use of AFLP markers allowed the identification of five strong clusters through estimates of genetic similarities. This classification did not group the lines by either their genetic background or their fertility reaction. This study provides information to identify specific combinations that would help to understand heterotic relationships in sorghum, and support the suggestions made by Menz and Gabriel that races in sorghum are not well defined.
144

Measurement of high voltage using Rutherford backscattering spectrometry

Abrego, Celestino Pete 25 April 2007 (has links)
A novel variation of Rutherford Backscattering Spectrometry (RBS) has been utilized to measure a high voltage collected on an aluminum target by Direct Energy Conversion. The maximum high voltage on the target was measured to be 97.5 kV +/- 2 kV. The resistance of the circuit was then calculated based on the current driving different target voltages. The resistance was calculated to be 199.4GΩ +/- 5%. It was shown that by simply measuring the neutral particles’ energy spectra, the voltage on the target and resistance of the circuit can be found with certainty. The experimental data agree well with previous work and with the scattering theory developed. Thus, the capability of RBS has been extended to measure high voltages generated by direct energy conversion; this is something that has not been done before.
145

Conception en génie électrique à l'aide d'éléments caractérisés

Demni, Houssem Eddine Piquet, Hubert. January 2005 (has links)
Reproduction de : Thèse de doctorat : Génie Électrique : Toulouse, INPT : 2004. / Titre provenant de l'écran-titre. Bibliogr. 45 réf.
146

Sensible exercises of the soul : a study of conversion in Jonathan Edwards /

Pipes, Elizabeth. January 2001 (has links)
Thesis (M.A.)--Wheaton College Graduate School, 2001. / Includes bibliographical references (leaves 126-128).
147

Analysis of amorphous thin-film tandem solar cells and their component layers

Ibrahim, Kamarulazizi January 1989 (has links)
No description available.
148

AC mains voltage regulation by solid-state power conversiontechniques

侯經權, Hau, King-kuen. January 1990 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy
149

A precision determination of the k-shell Internal conversion coefficient of the 135.5 keV m4 transition in ¹⁹³[superscript m] Pt

Saleh, Ali Ibrahim 08 1900 (has links)
No description available.
150

The desalination potential for small communities in Southern Iran.

Kheirandish, Reza. January 1973 (has links)
No description available.

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