196,203 research outputs found
Direct Analysis of Selected N-Acyl-L-Homoserine Lactones by Gas Chromatography/Mass Spectrometry
No full textA rapid, simple and selective method involving direct separation by gas chromatography (GC) with electron ionization mass spectrometry (EI-MS) was employed to determine some N-acylhomoserine lactones (AHLs). Using GC/EI-NIS, simultaneous separation and characterization of AHLs were possible without prior derivatization. Informative fragmentation patterns were obtained to identify the structures of N-acyl chains of AHLs. Electron ionization resulted in a common fragmentation pattern with the most abundant ion at m/z 143 and other minor peaks at m/z 71, 57, and 43. The presence of AHLs in extracts of Burkholderia cepacia strains was achieved in selected ion monitoring mode by using the prominent fragment at m/z 143
Deutschland
No full textDietmar Frommberger, Philipp Grollmann, Isabelle Le Mouillour (geschäftsführend); Silvia Annen, Thomas Deißinger, Uwe Lauterbach, Junmin Li, Matthias Pilz, Thomas Schröder, Georg SpöttlThis country study presents vocational training in Germany. This includes the dual system of initial vocational training and the many different school-based vocational training courses, which also include extensive practical learning components. In addition, there are the numerous regional and national company and vocational further training qualifications, the various offers in the so-called transition area and hybrid courses in which vocational and university qualifications are combined, e.g. in dual studies
APPLICATION OF FTICR MASS SPECTOMETRY FOR THE EVALUATION OF LIGHT EFFECT ON POLAR COMPOUNDS IN ITALIAN CRUDE OIL
No full textThe use of the crude oil as primary source of energy has significant social and environmental impacts, from accidents and routine activities such as seismic exploration, drilling, and generation of polluting wastes. Crude oil is subject to certain degradation processes: biotic and abiotic degradation. The fate of crude oil under UV and solar irradiation was studied.
Compositions of the original and irradiated samples have been characterized by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR/MS) 7 T ThermoElectron that is capable of achieving the peak capacity needed to resolve individual components of a complex data matrix.
Conversion of measured masses from the IUPAC mass scale (12C = 12.00000 Da) to the Kendrick mass scale (CH2=14.00000 instead of 14.01565 Da) was performed to facilitate identification of homologous series. The van Krevelen diagram was also used for a convenient visual separation of heteroatom class and alkylation pattern.
Preliminary results shows the light influence on crude oil composition: our future work will be devoted to well understand the modification that sunlight irradiation induce on the nature of crude oil
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
APPLICATION OF FTICR MASS SPECTROMETRY FOR THE IDENTIFICATION OF POLAR COMPOUNDS IN ITALIAN CRUDE OIL
No full textThe use of the crude oil as primary source for the energy oblige necessarily the characterization of this matrix to the aim to estimate the impact in several contexts: productive and environmental.
Petroleum crude oil is a complex organic mixture, in terms of the number of chemically distinct constituents: is composed of unsaturated and saturated hydrocarbons, heteroatoms (such as N, S, and O), as well as a small percentage of metals, particularly vanadium, nickel, iron and copper. The hydrocarbon fraction can be as high as 90% by weight in the lighter oils, compared to about 70% in heavy crude oil. A majority of the heteroatom free aromatics contain paraffinic chains, naphthalene rings, and aromatic rings side by side.
Heteroatomic compounds (NSO) make up a relatively small portion of crude oils, less than 15%12, but have significant implications because your presence and composition, that depend of the origin of the crude oil, can cause of positive and negative effects in the transformations process.
A variety of techniques have been employed to examine the structure of these aromatic species.
Compositions of the saturated hydrocarbons have been well characterized by gas chromatography mass
spectrometry (Zadro et al,1985), two-dimensional gas chromatography coupled to mass spectrometry (Wang et al.,2005), high-resolution mass spectrometry (Guan et al.,1996) , and liquid chromatography mass spectrometry (Qian, 1992; Hsu et al.1991).
However, comparatively little is known about the less abundant polar species or heavy crude oils, whose
compositional complexity far exceeds the peak capacity of typical analytical techniques.
Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR/MS) is capable of achieving the peak capacity needed to resolve individual components of a complex data matrix. In the last years FT-ICR/MS has received considerable attention for its ability to make mass measurements with a combination of resolution and accuracy that is higher than any other mass spectrometer.
In particular in recent work Marshall and co-authors demonstrated the unique utility of high field (9.4 T) of Electrospray Ionisation Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR/MS) to resolve and identify the polar species found in all petroleum distillates and for the identification of compounds in crude oils without prior chromatographic separation (Qian et al, 2001).
In this work we show a preliminary results obtained studying an Italian crude oil sample belonging to the well area, sited into the Viggiano countryside in the Basilicata region (Southern Italy) and the same oil after deterioration simulation, naturally occurring in the external environments (soil, water), by means of UV irradiation.
The analysis were realised using ESI/FT-ICR-MS 7 T Thermo Electron installed at Basilicata University and a NANOESI/FT-ICR-MS 12 T installed at GSFNational Research Centre for Environment and Health,
Institute for Ecological Chemistry, Neuherberg, Germany. The aim was to compare two instruments characterised by a different work philosophy
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
Intern experience at CH���M Hill, Inc.: an internship report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical referencesA review of the author's internship experience with CH���M HILL, Inc.
during the period September 1975 through May 1976 is presented. During this nine month
internship the author worked as an Engineer II in the Industrial Processes discipline of this
large consulting engineering firm... The author's prime responsibility was as one of three
lead design engineers on the design of a large wastewater treatment facility for a pulp mill
in Hoquiam, Washington owned by ITT Rayonier Inc. The work generally consisted of the design
of individual treatment units and associated piping and pumping. The purpose of the project
was to provide wastewater treatment capabilities that would satisfy the effluent limitations
(standards) imposed upon the mill by the State of Washington Department of Ecology and the
U.S. Environmental Protection Agency. The author's assignment also entailed necessary
interaction with the project manager and other CH���M HILL design engineers and support staff
members, the client's representatives, and representatives of two other consulting engineering
firms working on the project. Thus, the internship position at CH���M HILL provided considerable
experience coordinating the author's work with the work of other engineers, guiding the design
and administrative efforts of a support staff, and interacting regularly with the client and
other consulting firms. This broad exposure to a variety of engineering and organizational
problems provided a valuable educational experience
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