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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

The amount and utilization of organic phosphorus in soils

Gerard, C. J.(Cleveland Joseph) January 1950 (has links)
Call number: LD2668 .T4 1950 G4 / Master of Science
142

A CO2 capture technology using carbon nanotubes with polyaspartamide surfactant

Ngoy, Jacob Masiala 13 July 2016 (has links)
A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy Johannesburg, 2016 / Technologies for the separation of CO2 from flue gas require a feat of engineering for efficient achievement. Various CO2 capture technologies, including absorption, adsorption, cryogenics and membranes, have been investigated globally. The absorption technology uses mainly alkanolamine aqueous solutions, the most common being monoethanolamine (MEA); however, further investigation is required to circumvent its weakness due to degradation through oxidation, material corrosion and high energy costs required for regeneration. Attractive advantages in adsorption technology, including the ability to separate the more diluted component in the mixture with a low energy penalty, have been a motivation for many researchers to contribute to the advancement of adsorption technology in CO2 capture. The challenge in CO2 adsorption technology is to design a hydrophobic and biodegradable adsorbent with large CO2 uptake, high selectivity for CO2, adequate adsorption kinetics, water tolerance, and to require low levels of energy for regeneration processes. The existing adsorbent such as activated carbon, silica gel, zeolites, metal organic frameworks and others, have been ineffective where moisture occurs in flue gas. This work provides an advanced adsorption technology through a novel adsorbent, MWNT-PAA, designed from the noncovalent functionalization of multi-walled carbon nanotubes (MWNTs) by polyaspartamide (PAA) as product of amine grafted to polysuccinimide (PSI). Three types of PAA were prepared using ethylenediamine (EDA), 1, 3 propanediamine (PDA) and monoethanolamine (MEA) drafted to PSI to give PSI-EDA, PSI-PDA and PSI-MEA respectively. The CO2 adsorption capacity was 13.5 mg-CO2/g for PSI-PDA and 9.0 mg-CO2/g for PSI-MEA, which decreased significantly from PSI where the CO2 adsorption capacity was 25 mg-CO2/g. PSIEDA was selected as PAA, because the CO2 adsorption capacity was 52 mg-CO2/g which doubled from PSI. The polymer polyethylenimine (PEI), the most commonly polymer used in CO2 capture, was found to be non-biodegradable, while the polymer PAA showed the presence of CONH as a biodegradable bond functionality, occurring in the MWNT-PAA, as confirmed through Fourier Transform Infrared (FTIR) analysis. The adsorbent MWNT-PAA was demonstrated to have a water tolerance in the temperature range 25-55 ℃, where CO2 adsorption capacity increased with the increase of water in the adsorbent. The highest CO2 adsorption capacity recorded was 71 mg-CO2/g for the moist MWNT-PAA using 100% CO2 and 65 mg-CO2/g for the mixture of 14% CO2 with air. Under the same conditions, the dry MWNT-PAA adsorbed 70 and 46 mg-CO2/g respectively (100%, 14% CO2). The 2 regenerability efficiency of the MWNT-PAA absorbent was demonstrated at 100 ᵒC; after 10 cycles of adsorption-desorption 99% of adsorbed gas was recovered in the desorption process. The heat flow for the thermal swing adsorption system resulted in the net release of heat over the complete cycle; a cycle includes adsorption (heat release) and desorption (heat absorbance). Thus, this MWNT-PAA adsorbent demonstrates an advantage in terms of overall energy efficiency, and could be a competitive adsorbent in CO2 capture technology.
143

Evaluation of seven materials as sources of zinc for soybeans, Glycine max (L.)

Salako, Enoch Abiodun January 2011 (has links)
Digitized by Kansas Correctional Industries
144

Soil organic phosphorus

Steward, John Harrold January 1971 (has links)
xv, 130 leaves : ill. ; 26 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1971) from the Dept. of Agricultural Biochemistry and Soil Science, Waite Agricultural Research Institute, University of Adelaide
145

Bruk av standard kontorapplikasjoner for lagring i et proprietært Content Management System

Pedersen, John Arne Skjervold January 2003 (has links)
<p>Content Management Systemer (CMS) tas i bruk i stadig flere bedrifter. Bred funksjonalitet støtter opp under stadig flere prosesser. Dette fører til spesialiserte og ofte kompliserte grensesnitt som brukeren må forholde seg til, og utgjør en stor kostnad ved opplæring i forbindelse med bytte av CMS. </p><p>Denne rapporten ser på konseptet sømløs integrasjon mellom arbeidsverktøy og CMS. Med sømløs integrasjon menes at innholdsarkivet i CMS’et integreres i brukerens arbeidsmiljø. På denne måten usynliggjøres CMS’et og brukeren forholder seg til innholdsarkivet som om det var en lokal filstruktur. Denne typen integrasjon muliggjøres ved hjelp av WebDAV. WebDAV er en protokoll for kommunikasjon mellom et CMS og en klient. Ved å benytte Microsofts WebDAV-klient WebFolders kan et WebDAV-kompatibelt CMS navigeres og anvendes som en vanlig Windows-mappe, og CMS’et oppleves som integrert med arbeidsmiljøet. </p><p>For å evaluere muligheten for slik integrasjon ble WebDAV-støtte implementert i et proprietært CMS. Her har det vist seg at CMS’et tilbød mesteparten av funksjonaliteten som benyttes i WebDAV, så en implementasjon innebar i hovedsak mapping av WebDAV-funksjoner til eksisterende funksjonalitet. I tillegg til generell støtte for WebDAV-protokollen ble det implementert funksjonalitet for ekstrahering av metadata og import av filer fra to WebDAV-kompatible applikasjoner, Microsoft Word og Adobe Framemaker. Ved å ha mulighet til å ekstrahere metadata fra dokumenter kan merking av metadata flyttes vekk fra innholdsarkivet og ut i sluttbrukerprogrammene, enda et steg på veien mot sømløs integrasjon. Importfunksjonalitet gjør at filene som importeres blir innholdsdokumenter i CMS’et i motsetning til kun filer. Dermed kan tredjepartsapplikasjoner brukes til å generere og revidere innhold til CMS’et. </p><p>En brukertest av prototypeimplementasjonen ga ikke noen definitive svar, men tydet på at sømløs integrasjon kan ha postensiale, om ikke i situasjonen som ble testet. Her var brukeren fornøyd med eksisterende arbeidssituasjon og så liten grunn til å endre, selv om hun mente den nye metoden kunne være nyttig. Selv om WebFolder sannsynligvis er den mest brukte WebDAV-klienten har testing vist at den er svært begrenset i metadatahåndtering og støtter heller ikke låsing av filer. Dette begrenser de situasjoner der sømløs integrasjon ved WebDAV kan benyttes. </p><p>WebDAV implementeres i stadig flere produkter, og et CMS som støtter WebDAV vil kunne integreres med et stadig økende antall WebDAV-kompatible produksjonsverktøy. Sømløs integrasjon med WebDAV er ikke aktuelt i alle situasjoner, men ettersom produktene som støtter protokollen utvikles vil også integrasjonen og bruksnytte forbedres.</p>
146

Transformations of sulfur in wetland rice soils

Islam, M. Mujibul 26 June 1992 (has links)
Graduation date: 1993
147

Framing the internet in China cross-cultural comparisons of newspapers' coverage in China, Hong Kong, Singapore, the United States and the United Kingdom /

Zhou, Xiang. January 2006 (has links) (PDF)
Thesis (Ph.D.)--The University of Tennessee, Knoxville, 2006. / Adviser: Catherine A. Luther. Includes bibliographical references (p. 188-213)
148

The effects of processing on sodium-potassium and calcium-phosphorus ratios in foods

Ronan, Kathleen M. 04 June 1981 (has links)
The objective of this study was to determine the effects of processing on sodium - potassium and calcium - phosphorus ratios in tuna canned in oil and in water, peanut butter, white and whole wheat flours. Mineral levels were determined by atomic absorption spectrophotometry in food samples at various stages in the production of these finished products. The average sodium - potassium ratios of the tuna samples were: 1.37 raw, 1.24 precooked, 1.87 canned in oil and 1.61 canned in water. Processing did not significantly effect sodium and potassium ratios in canned tuna. The average calcium - phosphorus ratios of the tuna samples were: 0.034 raw, 0.024 precooked, 0.034 canned in oil and 0.065 canned in water. The ratio of the canned in water meat was significantly effected by processing. The average sodium - potassium ratios of the peanut samples were: 0.034 raw, 0.043 roasted, 0.031 blanched and 0.781 peanut butter. The ratio of peanut butter was significantly greater than the ratios of the other peanut samples. The average calcium - phosphorus ratios of the peanut samples were: 0.148 raw, 0.121 roasted, 0.141 blanched and 0.128 peanut butter. These ratios were not significantly effected by processing. The average sodium - potassium ratio was 0.16 in white flours, 0.84 in whole wheat flour and 0.89 in the kernel. The average calcium - phosphorus ratio was 0.14 in white flours, 0.07 in whole wheat flour and 0.07 in the kernel. The ratios of the kernel and whole wheat flour were not significantly different. Processing significantly effected the ratios of the white flour. The preferred concentration of sodium chloride and a 1:1 sodium - potassium chloride mixture in white and whole wheat breads was also studied. Bread samples were made with 1.0%, 0.75% and 0.5% levels of both salt treatments. They were evaluated by an untrained flavor panel for overall desirability with a nine point hedonic scale. The judges preferred a sodium chloride white bread with a 7.0 sodium - potassium ratio, and a sodium chloride whole wheat bread with a 3.29 ratio. These ratios were both lower than those found in commercial products. White and whole wheat breads made with 0.75% sodium chloride were as acceptable as breads made with 1.0% 1:1 sodium - potassium chloride mixture. The sodium - potassium ratio of the salt mixture white bread was 1.20 and the ratio of the whole wheat bread was 0.91. The addition of salt to finished products for flavor had an effect on the sodium - potassium ratio of the foods studied. Also, reducing the amount of added salt to commercial breads and replacing some sodium chloride with potassium chloride were acceptable means of lowering the sodium - potassium ratios of white and whole wheat breads. / Graduation date: 1982
149

Iron availability from corn tortillas and cooked beans (Phaseolus vulgaris) : a study on the effect of fiber

Garcia-Lopez, Jesus Salvador 23 June 1981 (has links)
Absorption of iron from foods has been reported to be inhibited by various factors including some diet components. Fiber from different sources has been observed to bind ferrous iron. This may be the reason for iron deficiencies observed in populations that consume diets high in non-digestible materials. The effect of different levels of fiber from corn tortillas and cooked beans on iron availability in the rat was studied. Iron-depleted rats were fed test diets containing different levels of iron and fiber and the diets were tested for their hemoglobin repletion ability. Estimation of the neutral detergent fiber (NDF) in corn tortillas and cooked beans and the soluble and ionizable iron in the test foods and diets were also determined. Corn tortillas contained 6.53% NDF. Raw beans contained 5.80% NDF and increase to 15.75% upon cooking. In cooked beans, 60.16% of the total iron is in the insoluble form while only 20.3% of the total iron in corn tortillas is insoluble. The mean relative biological value (RBV) for the test diets was 55.0 ± 19.0% with values ranging,from 40.41 ± 12.50% to 64.34 ± 11.10% compared to that of ferrous sulfate (100% available). Fiber or iron level had no significant effect on iron availability, however, a ratio of 1.78 of corn tortilla to cooked beans showed the highest degree of iron availability. Percent efficiency of the test diets to incorporate iron into hemoglobin ranged from 11.70 ± 1.4% for a diet containing 25 ppm iron and 15% NDF to 25.61 ± 6.10% for 35 ppm iron, 10% NDF diet. The control diet containing 30 ppm ferrous sulfate had a 43.0 ± 8.7% efficiency. Percent efficiency seems to show less variability in the determination of iron availability from foods than RBV. A significant correlation (p < 0.01) between soluble iron at pH 1.35 in vitro and percent efficiency was observed. This method could be used to predict iron availability for different foods. / Graduation date: 1982
150

Bruk av standard kontorapplikasjoner for lagring i et proprietært Content Management System

Pedersen, John Arne Skjervold January 2003 (has links)
Content Management Systemer (CMS) tas i bruk i stadig flere bedrifter. Bred funksjonalitet støtter opp under stadig flere prosesser. Dette fører til spesialiserte og ofte kompliserte grensesnitt som brukeren må forholde seg til, og utgjør en stor kostnad ved opplæring i forbindelse med bytte av CMS. Denne rapporten ser på konseptet sømløs integrasjon mellom arbeidsverktøy og CMS. Med sømløs integrasjon menes at innholdsarkivet i CMS’et integreres i brukerens arbeidsmiljø. På denne måten usynliggjøres CMS’et og brukeren forholder seg til innholdsarkivet som om det var en lokal filstruktur. Denne typen integrasjon muliggjøres ved hjelp av WebDAV. WebDAV er en protokoll for kommunikasjon mellom et CMS og en klient. Ved å benytte Microsofts WebDAV-klient WebFolders kan et WebDAV-kompatibelt CMS navigeres og anvendes som en vanlig Windows-mappe, og CMS’et oppleves som integrert med arbeidsmiljøet. For å evaluere muligheten for slik integrasjon ble WebDAV-støtte implementert i et proprietært CMS. Her har det vist seg at CMS’et tilbød mesteparten av funksjonaliteten som benyttes i WebDAV, så en implementasjon innebar i hovedsak mapping av WebDAV-funksjoner til eksisterende funksjonalitet. I tillegg til generell støtte for WebDAV-protokollen ble det implementert funksjonalitet for ekstrahering av metadata og import av filer fra to WebDAV-kompatible applikasjoner, Microsoft Word og Adobe Framemaker. Ved å ha mulighet til å ekstrahere metadata fra dokumenter kan merking av metadata flyttes vekk fra innholdsarkivet og ut i sluttbrukerprogrammene, enda et steg på veien mot sømløs integrasjon. Importfunksjonalitet gjør at filene som importeres blir innholdsdokumenter i CMS’et i motsetning til kun filer. Dermed kan tredjepartsapplikasjoner brukes til å generere og revidere innhold til CMS’et. En brukertest av prototypeimplementasjonen ga ikke noen definitive svar, men tydet på at sømløs integrasjon kan ha postensiale, om ikke i situasjonen som ble testet. Her var brukeren fornøyd med eksisterende arbeidssituasjon og så liten grunn til å endre, selv om hun mente den nye metoden kunne være nyttig. Selv om WebFolder sannsynligvis er den mest brukte WebDAV-klienten har testing vist at den er svært begrenset i metadatahåndtering og støtter heller ikke låsing av filer. Dette begrenser de situasjoner der sømløs integrasjon ved WebDAV kan benyttes. WebDAV implementeres i stadig flere produkter, og et CMS som støtter WebDAV vil kunne integreres med et stadig økende antall WebDAV-kompatible produksjonsverktøy. Sømløs integrasjon med WebDAV er ikke aktuelt i alle situasjoner, men ettersom produktene som støtter protokollen utvikles vil også integrasjonen og bruksnytte forbedres.

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