Your Guide Through The Information Jungle
“If you hold a cat by the tail you learn things you cannot learn any other way.” -- Mark Twain (American Humorist, Writer and Lecturer. 1835-1910)
One of the quickest ways to get up to speed on an unfamiliar technology is to read a thesis or dissertation on the subject.
One of the fastest ways to discover available theses and dissertations is to search WorldCat.
According to Wikipedia (www.wikipedia.org) …
“WorldCat is a union catalog which itemizes the collections of 71,000 libraries in 112 countries which participate in the Online Computer Library Center (OCLC) global cooperative. It is built and maintained collectively by the participating libraries.”
WorldCat is a service provided by many public libraries. Houston Public Library (http://www.houstonlibrary.org) offers the service to registered library patrons at no charge via the Internet. All you need is a library card.
WorldCat Thesis Example
· Ask your public library how to access WorldCat
· Access WorldCat
· Click Advanced Search
· Select search criteria … in this example, we search for DIBENZOTHIOPHENE as a KEYWORD, and select THESIS/DISSERTATION as a SUBTYPE
· Browse the results list … in this example, one of the items of interest is “Oxidation of dibenzothiophene to dibenzothiophene sulfone using metal nanoparticles supported on silica”
· Google the item for more information.
Finally, when you decide you want to read the full text of a thesis or dissertation, your public library again can help … through a service called ILL – Interlibrary Loan.
If you take away nothing else from this post, take away this thought … ask your librarian. He or she can guide you through the jungle to find the information you need.
Scroll through the JPGs below … they illustrate the points made above.
After identifying a thesis/dissertation of interest in WorldCat, Google the title for more inormation. Sometimes you will be lucky enough to find full text. In other cases, you will find an abstract which will tell you enough to determine whether to purchase the item, or request it through ILL – Interlibrary Loan.
///////
Oxidation of dibenzothiophene to dibenzothiophene sulfone using metal nanoparticles supported on silica
Karina Castillo, University of Texas at El Paso
Abstract
Silica and nanoparticles of Pt, Au, and Ag supported on silica were tested for the ability to oxidize dibenzothiophene (DBT) to sulfone. High performance liquid chromatography was used to study the removal of DBT from solution. In addition, X- ray diffraction, infrared spectroscopy and Raman Spectroscopy were used to characterize the product of the oxidation reaction. Further studies involved the use X-ray absorption spectroscopy to characterize the nanoparticle catalysts before and after the oxidation reaction. To better understand the reaction, silica was synthesized at different pHs using three different acids. The acids used to synthesize the silica were HCl, HNO3 , and H2 SO4 . The effect of SiO 2 calcination temperature on the reaction was studied by drying silica at different temperatures. In addition, the oxidation reactions were performed at different temperatures and in different solvents. The reaction temperature used to test silica ranged between 115°C and 160°C when using decahydronaphthalene (decalin) as a solvent. Further studies were performed using high boiling point solvents tetrahydronaphthalene (tetralin) and n-dodecane. The percentage removal of DBT was similar when any of the three solvents was used in the reaction. However, when lower boiling point solvents were tested, such as hexane and heptane, no oxidation was observed. Furthermore, oxidation was not observed when the reactions were performed at the boiling point of each tested solvent. Silica synthesized at pH 0 using HCl, removed up to 70% of dibenzothiophene. However, a 90% removal was observed when commercially available silica was tested in this reaction. Studies were performed to determine activation energy of the reactions using silica and then using the metal nanoparticles supported on silica. The activation energy was determined by testing each catalyst at three different temperatures. Each reaction was sampled every 30 minutes for up to 2 h. The Pt/SiO2 catalyst had an activation energy of 20.26 kJ/mol, the Au/SiO2 catalyst an activation energy of 47.04 kJ/mol, and the activation energy of the Ag/SiO2 catalyst was 77.31 kJ/mol. In addition, the activation energy of SiO2 catalyst was determined to be 115.56 kJ/mol. The Pt/SiO2 catalyst had the lowest activation energy of all the studied catalysts. Recycling studies showed the Au/SiO 2 catalyst maintained the highest catalytic activity when tested four consecutive times in the reaction. Infrared spectroscopy, X-ray diffraction and Raman spectroscopy confirmed that dibenzothiophene was oxidized to dibenzothiophene sulfone in the reaction. Furthermore, extended X-ray absorbed fine structure (EXAFS) showed the metal nanoparticles grew after the reaction. In addition, EXAFS studies also showed the silver catalyst converted to Ag2 S after use in the oxidation reaction.
Karina Castillo, "Oxidation of dibenzothiophene to dibenzothiophene sulfone using metal nanoparticles supported on silica" (January 1, 2010). ETD Collection for University of Texas, El Paso. Paper AAI3409143.
http://digitalcommons.utep.edu/dissertations/AAI3409143
///////
Follow this blog (http://www.desulf.blogspot.com/) … and advise your friends and associates to do so also
