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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.
211

Aqueous alpha-lipoic acid solutions for removal of arsenic and mercury from materials used for museum artifacts

Cross, Peggi January 2007 (has links)
Recorded use of pesticides in the conservation of artifacts dates back to the 16th century. Museums today are faced with a tremendous task of identification and remediation of pesticides from artifacts in order to protect museum workers and the general public. In addition, artifacts are being repatriated by Native American tribes for use in cultural ceremonies which may subject the practitioner to health risks. Arsenic and mercury salts are among the pesticides that were used that are highly persistent and toxic. The primary challenge lies in removing these hazardous and persistent metals without damaging the materials or pigments on the objects.Concentrated aqueous alpha-lipoic acid solutions were developed for removing arsenic and mercury pesticides from materials commonly used in museum artifacts. The alpha-lipoic acid solutions were reduced using natural sunlight or laboratory ultraviolet lamps to enhance the binding of arsenic. The solubility of alpha-lipoic acid in various organic and inorganic solutions was determined and environmental parameters that impact the reduction and solubility, such as pH and temperature, were examined. The kinetics of the reaction of arsenic (III) with reduced lipoic acid was examined by varying the reduced lipoic acid, base and arsenic concentration as well as temperature and stirring conditions. The results indicated that the reaction occurs at a moderate rate primarily within 8 seconds in air. The reaction is chemically rate limited enhanced at higher temperatures and lower pH. Aerobic conditions significantly decreased the extent of the reaction with increased stirring rate. This impact was minimized by using a nitrogen environment or by limiting agitation during the reaction step.The methods developed were capable of removing up to 1000 µg/cm2 arsenic (of sodium arsenite) from simulated artifacts to levels near the lower detection limit of the X-ray Fluorescence Spectrometer (1 µg/cm2) without leaving detectable residues according to Attenuated Total-Reflection Fourier Transform Infrared Spectroscopy. Similar results were achieved in removing mercury (of mercuric chloride) from non-sulfur containing materials; however, the solutions and processes developed were not capable of removing mercury from sulfur-containing materials such as wool and feathers.
212

The use of the thermotolerant yeast Kluyveromyces marxianus IMB3 for ethanol production from whey permeate at 45degC

Keogh, Myles Patrick January 1999 (has links)
No description available.
213

Asymmetric synthesis using chiral amines

Harrison, Michael John January 1990 (has links)
No description available.
214

Radical reactions leading to cyclic amino acids

Wilson, Michelle January 2000 (has links)
No description available.
215

The development of HPLC matrices for the rapid purification of oligonucleotides

Collins, Ian John January 1993 (has links)
No description available.
216

A mew method to estimate whole body protein turnover in man

Gowrie, Ian Joseph January 2002 (has links)
No description available.
217

The mechanism of aluminium toxicity to rhizobium

Johnson, Andrew C. January 1988 (has links)
No description available.
218

The beneficial and adverse effects of increasing N-3 polyunsaturated fatty acids (PUFA) intake on coronary heart disease (CHD) biomarkers

Leigh-Firbank, Elizabeth C. January 2000 (has links)
No description available.
219

The development of a continuous solid-state fermentation process for the production of fungal tannase

Van de Lagemaat, Juergen January 2001 (has links)
No description available.
220

The survival of Listeria monocytogenes during acid stress

Barker, Clive January 2000 (has links)
No description available.

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