Comparison of the Structures of Molecules in Coal and Petroleum Asphaltenes by Using Mass Spectrometry

2013 ◽  
Vol 27 (7) ◽  
pp. 3653-3658 ◽  
Author(s):  
Matthew R. Hurt ◽  
David J. Borton ◽  
Heewon J. Choi ◽  
Hilkka I. Kenttämaa
2005 ◽  
Vol 19 (4) ◽  
pp. 1548-1560 ◽  
Author(s):  
Sócrates Acevedo ◽  
Luis B. Gutierrez ◽  
Gabriel Negrin ◽  
Juan Carlos Pereira ◽  
Bernardo Mendez ◽  
...  

2020 ◽  
Vol 20 (5) ◽  
pp. 359-365
Author(s):  
L. I. Musin ◽  
L. E. Foss ◽  
K. V. Shabalin ◽  
O. A. Nagornova ◽  
D. N. Borisov ◽  
...  

The feasibility of the room temperature catalytic cyclization of hydrazine hydrate and acrylic acid in the presence of an acidic catalyst containing petroleum asphaltenes was explored. The effect of sulfocationite on the synthesis of the target pyrazolidin-3-one was studied. Reaction masses and their distillation residues were analyzed. Gas chromatography–mass spectrometry and electrospray ionization were used to reveal different individual, oligomeric and polymeric products. The most probable structures of the obtained products were proposed.


2000 ◽  
Vol 65 (8) ◽  
pp. 561-569
Author(s):  
Pavle Premovic ◽  
Dragan Djordjevic ◽  
Ivan Tonsa ◽  
Liliana López ◽  
Salvador Lomonaco ◽  
...  

High resolution mass spectrometry indicates that the isotopic abundance of 50Vanadium (V) of the Late Cretaceous La Luna petroleum asphaltenes and related source kerogen of marine origin (both highly enriched with V > 2000 ppm) is higher by about 3.5% than that of an inorganic vanadium source (VOS04?5H20, Merek). It is proposed that the difference in the 50V/51V values between the La Luna source kerogen/the associated petroleum asphaltenes and the inorganic source can be best ascribed to the biological processing of seawater V. The fact that the isotopic compositions of V vary over a very narrow range (2.46-2.50) suggest an essentially same (or similar) and fixed biological source of V.


Author(s):  
Philippe Fragu

The identification, localization and quantification of intracellular chemical elements is an area of scientific endeavour which has not ceased to develop over the past 30 years. Secondary Ion Mass Spectrometry (SIMS) microscopy is widely used for elemental localization problems in geochemistry, metallurgy and electronics. Although the first commercial instruments were available in 1968, biological applications have been gradual as investigators have systematically examined the potential source of artefacts inherent in the method and sought to develop strategies for the analysis of soft biological material with a lateral resolution equivalent to that of the light microscope. In 1992, the prospects offered by this technique are even more encouraging as prototypes of new ion probes appear capable of achieving the ultimate goal, namely the quantitative analysis of micron and submicron regions. The purpose of this review is to underline the requirements for biomedical applications of SIMS microscopy.Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue.


Author(s):  
K.K. Soni ◽  
D.B. Williams ◽  
J.M. Chabala ◽  
R. Levi-Setti ◽  
D.E. Newbury

In contrast to the inability of x-ray microanalysis to detect Li, secondary ion mass spectrometry (SIMS) generates a very strong Li+ signal. The latter’s potential was recently exploited by Williams et al. in the study of binary Al-Li alloys. The present study of Al-Li-Cu was done using the high resolution scanning ion microprobe (SIM) at the University of Chicago (UC). The UC SIM employs a 40 keV, ∼70 nm diameter Ga+ probe extracted from a liquid Ga source, which is scanned over areas smaller than 160×160 μm2 using a 512×512 raster. During this experiment, the sample was held at 2 × 10-8 torr.In the Al-Li-Cu system, two phases of major importance are T1 and T2, with nominal compositions of Al2LiCu and Al6Li3Cu respectively. In commercial alloys, T1 develops a plate-like structure with a thickness <∼2 nm and is therefore inaccessible to conventional microanalytical techniques. T2 is the equilibrium phase with apparent icosahedral symmetry and its presence is undesirable in industrial alloys.


Author(s):  
Bruno Schueler ◽  
Robert W. Odom

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) provides unique capabilities for elemental and molecular compositional analysis of a wide variety of surfaces. This relatively new technique is finding increasing applications in analyses concerned with determining the chemical composition of various polymer surfaces, identifying the composition of organic and inorganic residues on surfaces and the localization of molecular or structurally significant secondary ions signals from biological tissues. TOF-SIMS analyses are typically performed under low primary ion dose (static SIMS) conditions and hence the secondary ions formed often contain significant structural information.This paper will present an overview of current TOF-SIMS instrumentation with particular emphasis on the stigmatic imaging ion microscope developed in the authors’ laboratory. This discussion will be followed by a presentation of several useful applications of the technique for the characterization of polymer surfaces and biological tissues specimens. Particular attention in these applications will focus on how the analytical problem impacts the performance requirements of the mass spectrometer and vice-versa.


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