“Sing then the core of dark and absolute oblivion where the soul at last is lost in utter peace.” -- D.H. Lawrence (British Poet, Novelist and Essayist, 1885-1930)
I have worked with engineers most of my professional life. Most of them thought they were smarter than me. Some of them actually were. But, despite my deficient intelligence, in every case I was able to help them find the information they needed to do their work.
Not that they could not have found the information themselves … but I could find it more quickly, allowing them to spend their valuable time on the work they had been hired to perform.
That said, you can help your librarian or research assistant help you by educating him or her on key words and concepts related to your topic of interest. The small amount of time you spend on the education process will yield huge benefits to you down the line.
Begin the education process by providing one or more Core Documents. Core documents provide in concise and easy to digest terms the key words and concepts that someone new to your topic can use to construct search strategies that will unearth items that can be useful to your research effort.
Obviously your information professional can find such core documents on his or her own … but if you are already aware of significant articles or dissertations, help the information professional help you by suggesting the core documents as a preliminary step.
Dissertations, in many cases, make ideal Core Documents. A typical dissertation begins with a detailed abstract of the work performed by the doctoral candidate. He or she has to display both a knowledge of the topic of the dissertation, and the significance of the candidate’s work. The abstract, therefore, contains just the sort of key words and concepts that can be used by an online researcher to identify and locate other documents of interest to your research team.
Here is an example of what I am talking about …
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Desulfurization of Hydrocarbon Fuels at Ambient Conditions Using Supported Silver Oxide-Titania Sorbents
Dissertation by Sachin Appukuttan Nair
A dissertation submitted to the Graduate Faculty of Auburn University in partial fulfillment of the requirements for the Degree of Doctor of Philosophy
Auburn, Alabama December 13, 2010
Bruce J Tatarchuk, Chair, Professor Director of Chemical Engineering
Yoon Y Lee, Alumni Professor of Chemical Engineering
William Ashurst, Assistant Professor of Chemical Engineering
Dong-Joo (Daniel) Kim, Associate Professor of Materials Engineering
Abstract
Sulfur in refined fuels is considered a significant cause for atmospheric pollution such as acid rain and smog. Sulfur is also a poison for electrocatalysts in fuel cells and catalysts in hydrocarbon refining and reformation processes. Thus sulfur removal is essential for large scale production of transportation fuels as well as in smaller scales for mobile and stationary fuel cell and reforming applications. Hydro desulfurization (HDS) is the most prevalent desulfurization technology used currently. Several alternative technologies have been reported to be effective in sulfur removal from liquids such as catalytic oxidation, biological sulfur removal and membrane separation. The presented work focuses on the formulation, optimization and mechanistic investigations of adsorptive desulfurization adsorbents for liquid fuels at ambient conditions. Dispersed silver oxides on supports such as TiO 2 , γ-Al 2 O 3 and SiO 2 were observed to be effective desulfurizing agents for refined fuels at ambient conditions. Among the supports, TiO 2 was found to be the most stable. Using titanium oxide of varying surface characteristics, it was determined that sulfur capacity corresponded to the specific surface area. Increasing the Ag loading on the support was observed to decrease dispersion and simultaneously decrease the sulfur capacity. At 4 Wt.% Ag loading, the sulfur capacity of the sorbent was 6.3 mgS/g for JP5 fuel containing 1172 ppmw sulfur. The sorbent composition was thermally regenerated (450:C) to 10 cycles using air as a stripping medium. Variation in desulfurization efficiency between JP5, JP8 and a lighter fraction of JP5 was established and correlated to the variation in sulfur speciation of the fuels. Lower concentration of trimethyl benzothiophenes in the lighter fraction JP5 resulted in the highest sulfur capacity demonstrated by Ag/TiO 2 . These studies on performance, effects of composition, fuel chemistry and regeneration procedures are presented in Chapter III. With the composition and performance of the sorbent established, synthesis procedures were optimized considering impregnation, drying and calcination stages. The effect of synthesis conditions on the sulfur capacity was correlated to the resulting pore structure and dispersion of Ag (Chapter IV). Incipient wetness among the various impregnation techniques resulted in the highest sulfur capacity. Calcination temperatures above 500 :C were observed to degrade the pore structure and thus lower the sulfur capacity of the sorbent. Characterization techniques such as BET surface area measurements, oxygen chemisorption, temperature programmed reduction (TPR), ultraviolet spectroscopy were used to study the adsorbent composition. The variation in the oxidation state of Ag with weight loading was determined using TPR and thermogravimetry. At 4% Ag loading approximately 28% of the deposited Ag was found to exist as the oxide. Lowering the metal loading significantly increased the dispersion. These dispersed Ag oxides were observed to be stable to temperatures of 550:C. UV spectroscopy showed absorption bands representing oxides of Ag while bands representing metallic Ag were absent. It was therefore concluded that a majority of the Ag at the adsorption interface existed in the oxide phase. This indicated an alternative mechanism of sulfur removal compared to other transition metal based sorbents where the active material is considered to be the metal ion. Several aspects to be considered during the scale-up of adsorption units such as bed configuration, liquid face velocity and bed temperature and the effect on sulfur capacity was addressed as well. Having established the composition of the sorbent with respect to the oxidation state of Ag present, the dispersion of Ag and pore structure, several studies were carried out to determine the mechanism of sulfur removal in these materials (Chapter V & VI). Variation in desulfurization efficiency between sulfur aromatics varying in structure aspects such as aromaticity and presence of side chains were linked to the chemistry of the active center. These studies established that the active centers were acidic in nature. Probe molecules were used to poison the active centers and subjected to desulfurization studies. Surface complexes formed from the probe molecules were also identified using IR spectroscopy. These experiments indicated that the surface group responsible for the sulfur capacity was single or geminal hydroxyl groups. Equilibrium isotherms were also established for thiophene, benzothiophene, dibenzothiophene and 46 dimethyl dibenzothiophene at 22, 40 and 60:C and fitted to Langmuir, Freundlich and Fritz-Schlunder models (Chapter VII). The adsorption data followed the Langmuir model indicating that sulfur removal was effected by associative physical adsorption.
source: http://etd.auburn.edu/etd/bitstream/handle/10415/2371/Sachin%20Nair_Dissertation_ETD%20Rev2_PD5.pdf?sequence=2
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A core resource to consider is the Desulfurization Blog (http://www.desulf.blogspot.com/ … follow it and recommend it to colleagues and friends.
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