scholarly journals King's Oxygen Compound

2010 ◽  
Vol 112 (1) ◽  
pp. 219-219
Author(s):  
George S. Bause
Keyword(s):  
Oxygen Compound

ChemInform Abstract: Research on the Calcium Inhibition of a Heterocyclic Oxygen Compound Series.

ChemInform ◽  
1988 ◽  
Vol 19 (20) ◽  
Author(s):  
G. MOUYSSET ◽  
J. BELLAN ◽  
M. PAYARD ◽  
J. TISNE-VERSAILLES
Keyword(s):  
Oxygen Compound ◽  
Compound Series

Using polar nitrogen-, sulphur- and oxygen-compound compositions from ultra-high resolution mass spectrometry for petroleum fluid assessment in the Eagle Ford Formation, Texas

2019 ◽  
Vol 484 (1) ◽  
pp. 71-96 ◽  
Author(s):  
S. Poetz ◽  
S. Kuske ◽  
Y. Song ◽  
J. Jweda ◽  
E. Michael ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Depositional Environment ◽  
High Resolution Mass Spectrometry ◽  
Petroleum System ◽  
Oxygen Compound ◽  
Eagle Ford ◽  
Ft Icr Ms ◽  
Ft Icr ◽  
Resolution Mass

AbstractThe potential of polar compound compositions from electrospray ionization ultra-high resolution mass spectrometry (FT-ICR-MS) to characterize petroleum fluids as well as petroleum system processes is shown in the example of the Eagle Ford Formation in Texas, USA. A set of six black oil and nine source-rock bitumen samples is investigated with respect to its organic nitrogen-, sulphur- and oxygen-compound inventory in order to assess maturity, depositional environment, lithofacies and retention and migration behaviour. Compared to conventional geochemical tools based on molecular parameters from gas chromatographic analyses, FT-ICR-MS enables a maturity assessment from immature to late mature stage, which is barely influenced by source or depositional environment. Due to the increased molecular mass and polarity range of its target compounds, FT-ICR-MS is the most convincing tool to describe the retention and fractionation of polar compounds in a petroleum system.

ab initio-Rechnungen zur Tautomerie, Acidität und Basizität von 1-MethyIpyrazolin- 2-on-5 und seinen Schwefel und Selen Analogen / ab initio Calculations of the Tautomerism, the Acidity and the Basicity of 1-Methyl- pyrazoline-2-one-5 and the Corresponding Sulphur and Selenium Analogs

1997 ◽  
Vol 52 (4) ◽  
pp. 535-542 ◽  
Author(s):  
Galina Tschmutova ◽  
Hubertus Ahlbrecht
Keyword(s):  
Ab Initio ◽  
Relative Stability ◽  
Quantum Chemical ◽  
Ring Plane ◽  
Sulphur Compounds ◽  
Oxygen Compound ◽  
Selenium Compounds ◽  
Neutral Compounds ◽  
Different Levels ◽  
Reasonable Model

Quantum chemical calculations on the title compounds have been performed at different levels of theory in order to obtain a reasonable model capable of treating even larger systems with reliable results. The HF/6-31G*//PM3 model is shown to describe the cations reasonably well as compared to the corresponding ab initio results. The anions and neutral compounds yield reasonable results at the HF/ 6-31+G*//PM3 level. In the case of the oxygen compound the CH form is predicted to be the most stable tautomer at all levels of theory. The CH and the XH tautomer become energetically similar for the sulphur and selenium compounds, and the relative stability depends on the model used. All methods predict the acidity to increase in the order O<S<Se. Differences in basicity are not so pronounced. The most stable cation is always the N-protonated XH tautomer and is followed by the X-protonated CH tautomer. All other cations are calculated to be clearly higher in energy. The conformation of the XH bond depends on the nature of the heteroatom. Whereas the oxygen compounds prefer a coplanar orientation with respect to the ring plane, the selenium compounds strongly tend to rotate the XH bond out of the plane into a nearly perpendicular position. Both conformations are found for sulphur compounds.

scholarly journals The reaction of cytochrome o in Escherichia coli with oxygen. Low-temperature kinetic and spectral studies

1979 ◽  
Vol 184 (2) ◽  
pp. 379-389 ◽  
Author(s):  
R K Poole ◽  
A J Waring ◽  
B Chance
Keyword(s):  
Escherichia Coli ◽  
Low Temperature ◽  
Flash Photolysis ◽  
Spectral Characteristics ◽  
Spectral Studies ◽  
Oxygen Compound ◽  
Intact Cells ◽  
Lower Velocity ◽  
Cytochrome D ◽  
O2 Binding

1. The reactions of cytochrome omicron in intact cells of aerobically grown Escherichia coli with O2 and CO have been studied at low temperature. 2. Flash photolysis of CO-liganded cells in the presence of O2 and at temperatures between −79 and −102 degrees C results in the oxidation of kinetically heterogeneous beta-type cytochromes (including cytochrome omicron), but not of cytochrome d. 3. The reaction of reduced cytochrome omicron with O2 involves O2 binding to give intermediate(s) with spectral characteristics similar to that of the reduced oxidase-CO complex. Observation in the alpha-region suggests that unexplained ligand dissociation accompanies the initial O2 binding. 4. At temperatures below −98 degrees C, an ‘end point’ in the reaction is reached; further reaction and oxidation of cytochrome omicron occurs on raising the temperature. 5. There is a linear relationship between the rate of formation of the oxygen compound and the O2 concentration up to 0.5 mM. The second-order constant for its formation (k+1) is 0.91 M−1.S−1 at −101 degrees C. The reaction is not readily reversible, the value of k−1 being 1.4 × 10(-5) S−1 and the kd 1.5 × 10(-5) M. 6. The energy of activation for this reaction at low temperatures is 29.9kJ (7.1 kcal)/mol. 7. The reaction with O2 is distinguished from that with CO by the markedly lower velocity and high photolytic reversibility of the latter. 8. Comparisons are drawn between the intermediate(s) in the O2 reaction of cytochrome omicron in E. coli and those identified in other bacteria and in the reaction of cytochrome aa3 with O2.

A Study on Application of Surfactants in Cemented Carbides Ball Milling

2014 ◽  
Vol 893 ◽  
pp. 100-104
Author(s):  
Tang Kai ◽  
Yan Jie
Keyword(s):  
Mechanical Properties ◽  
Mechanical Property ◽  
Stearic Acid ◽  
Ball Milling ◽  
Magnetic Force ◽  
Cemented Carbides ◽  
Magnetic Saturation ◽  
Application Of Surfactants ◽  
Sem Images ◽  
Oxygen Compound

Several surfactants were studied in cemented carbides ball milling in this paper by analyzing cemented carbides mechanical properties and SEM images. Appropriate surfactants used in ball milling were selected to replace commonly used surfactant, stearic acid. Impacts of surfactants on hardness, magnetic force and magnetic saturation were also discussed. Oleic acid and AEO-3 as the better surfactant than stearic acid were selected after experiments. How containing oxygen compound affects the cemented carbide mechanical property cannot be recommended at this stage; further investigations are required.

Role of Oxygen in Growth of Carbon Nanotubes on SiC

2006 ◽  
Vol 527-529 ◽  
pp. 1575-1578 ◽  
Author(s):  
Wei Jie Lu ◽  
John Boeckl ◽  
W.C. Mitchel ◽  
J. Rigueur ◽  
W.E. Collins
Keyword(s):  
Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Structural Defects ◽  
Oxygen Species ◽  
Oxygen Compound ◽  
X Ray ◽  
Multi Wall Carbon Nanotubes

Carbon nanotubes (CNTs) grown on SiC are metal-free, well-aligned, and with low structural defects. In this study, CNT formation on SiC is examined in high vacuum (10-5torr) and ultra-high vacuum (10-8torr). Multi-wall carbon nanotubes and graphitic structures are the main products on the SiC surface at 1400-1800°C in 10-5torr. Under ultra-high vacuum, the decomposition rate of SiC is much lower than in high vacuum, indicating that SiC is decomposed by oxidation reaction. Using X-ray photoelectron spectroscopy (XPS), the intensity of the O1s peak at 530.3 eV decreases with increasing take-off angle, indicating that this oxygen species exists on the walls of CNTs. The results show that oxygen with a low pressure not only oxidizes SiC, but also forms a highly thermally stable carbon-oxygen compound, and interacts with the CNTs at high temperatures.

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