scholarly journals THERMODYNAMIC CALCULATIONS RELATING TO CHLORIDE VOLATILITY PROCESSING OF NUCLEAR FUELS. IV. THE GAS-PHASE REDUCTION OF URANIUM PENTACHLORIDE AND HEXACHLORIDE TO SOLID TETRACHLORIDE WITH CARBON MONOXIDE

1965 ◽  
Author(s):  
T. A. Gens
Keyword(s):  
Carbon Monoxide ◽  
Gas Phase ◽  
Thermodynamic Calculations ◽  
Nuclear Fuels ◽  
Phase Reduction

scholarly journals Selective reduction of iron and phosphorus from oolitic ore

2020 ◽  
Vol 63 (7) ◽  
pp. 560-567
Author(s):  
S. P. Salikhov ◽  
B. Suleimen ◽  
V. E. Roshchin
Keyword(s):  
Carbon Monoxide ◽  
Gas Phase ◽  
Solid Phase ◽  
Selective Reduction ◽  
Metallic Phase ◽  
Metal Phase ◽  
Phase Reduction ◽  
Reduction Of Iron ◽  
Phosphorus Reduction ◽  
Reductive Roasting

Possibility of selective solid-phase reduction of iron from oolitic ore has been experimentally confirmed. Solid phase reduction was carried out at temperatures of 850 and 1000 °C in CO atmosphere and in the mixture with solid carbon. Distribution of iron and phosphorus was investigated with scanning electron microscope. It was found that at temperature of 1000 °C minimum amount of phosphorus (up to 0.3 %) is transformed into the metallic phase at reduction by carbon monoxide. Upon reduction in mixture of ore with carbon, phosphorus content in metal phase reaches 1.0 – 1.3 % evenat temperature of 850 °C. Thermodynamic modeling of the processes occurring during reductive roasting of oolitic ore was carried out depending on temperature (1000 – 1400 K) and amount of carbon in the system. It is shown that reduction temperature and degree of phosphorus reduction vary depending on ratio of CO and CO2 in the gas phase. At temperatures below 892 °C, phosphorus is not reduced and all iron is in metal phase. With an increase in amount of carbon in the system, phosphorus appears in metal phase. With an excess of carbon in the system, all phosphorus is in metal phase at temperature of 892 °С. Thus, with a certain amount of carbon in the system and, correspondingly, with a certain ratio of CO and CO2 in gas phase, selective reduction of iron is possible without phosphorus reduction even at temperature of 1100 °С. Comparison of experimental results with results of thermodynamic calculation confirms possibility of se selective reduction of iron without phosphorus reduction only by carbon monoxide.

Coupled Mass and Heat Transport Models for Nuclear Fuels using Thermodynamic Calculations

2018 ◽  
Author(s):  
Srdjan Simunovic ◽  
Jake W. Mcmurray ◽  
Theodore M. Besmann ◽  
Emily Moore ◽  
Markus H. A. Piro
Keyword(s):  
Heat Transport ◽  
Thermodynamic Calculations ◽  
Nuclear Fuels ◽  
Transport Models

Investigation of Adsorption Effect of Carbon Monoxide on Coniine: A DFT Study

2021 ◽  
Vol 17 ◽  
Author(s):  
Siyamak Shahab ◽  
Masoome Sheikhi ◽  
Mehrnoosh Khaleghian ◽  
Marina Murashko ◽  
Mahin Ahmadianarog ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Gas Phase ◽  
Density Functional ◽  
Energy Gap ◽  
Adsorption Effect ◽  
Chemical Shift Tensors ◽  
Solvent Water ◽  
Donor And Acceptor ◽  
Before And After ◽  
Electron Donor And Acceptor

: For the first time in the present study, the non-bonded interaction of the Coniine (C8H17N) with carbon monoxide (CO) was investigated by density functional theory (DFT/M062X/6-311+G*) in the gas phase and solvent water. The adsorption of the CO over C8H17N was affected on the electronic properties such as EHOMO, ELUMO, the energy gap between LUMO and HOMO, global hardness. Furthermore, chemical shift tensors and natural charge of the C8H17N and complex C8H17N/CO were determined and discussed. According to the natural bond orbital (NBO) results, the molecule C8H17N and CO play as both electron donor and acceptor at the complex C8H17N/CO in the gas phase and solvent water. On the other hand, the charge transfer is occurred between the bonding, antibonding or nonbonding orbitals in two molecules C8H17N and CO. We have also investigated the charge distribution for the complex C8H17N/CO by molecular electrostatic potential (MEP) calculations using the M062X/6-311+G* level of theory. The electronic spectra of the C8H17N and complex C8H17N/CO were calculated by time dependent DFT (TD-DFT) for investigation of the maximum wavelength value of the C8H17N before and after the non-bonded interaction with the CO in the gas phase and solvent water. Therefore, C8H17N can be used as strong absorbers for air purification and reduce environmental pollution.

The Gas Phase Reactions of Recoil Sulfur Atoms with Carbon Monoxide and Carbon Dioxide1

1964 ◽  
Vol 68 (2) ◽  
pp. 318-322 ◽  
Author(s):  
Edward K. C. Lee ◽  
Y. N. Tang ◽  
F. S. Rowland
Keyword(s):  
Carbon Monoxide ◽  
Gas Phase ◽  
Gas Phase Reactions

COMPARATIVE ANALYSIS OF THE CONTENT OF TOXIC SUBSTANCES IN THE GAS PHASE OF AEROSOL OF CIGARETTES AND HEATED TOBACCO STICKS FOR ELECTRIC TOBACCO HEATING SYSTEMS

2020 ◽  
Author(s):  
С.Н. МЕДВЕДЕВА ◽  
Т.А. ПЕРЕЖОГИНА ◽  
Е.В. ГНУЧИХ
Keyword(s):  
Thermal Decomposition ◽  
Carbon Monoxide ◽  
Comparative Analysis ◽  
Gas Phase ◽  
Control Sample ◽  
Toxic Substances ◽  
Heating Systems

Представлены результаты анализа содержания монооксида углерода, бензола, 1,3-бутадиена в газовой фазе аэрозоля (ГФА) образцов нагреваемых табачных палочек (стики) для электрических систем нагревания табака, пяти марок коммерческих сигарет, контрольной сигареты 3R4F с помощью тестирования на курительной машине в стандартном режиме прокуривания ISO и интенсивном ISO Intense. Установлено значительное снижение содержания монооксида углерода, бензола и 1,3-бутадиена в аэрозоле образцов стиков по режиму ISO Intense и ISO. Количество образующегося монооксида углерода в ГФА образцов стиков составляет 2% от его содержания в ГФА образца контрольных сигарет 3R4F, что подтверждает отсутствие процессов термического разложения (пиролиза) табака. Определено, что в ГФА образцов стиков содержится значительно меньше вредных и потенциально опасных соединений. Установлено снижение содержания бензола и 1,3-бутадиена более чем на 99% по сравнению с контрольным образцом 3R4F и пятью образцами популярных в России марок сигарет. The results of the analysis of the content of carbon monoxide, benzene, 1,3-butadiene in the aerosol gas phase (AGPh) of heated tobacco sticks for electric tobacco heating systems, five brands of commercial cigarettes, 3R4F control cigarette using testing on a Smoking machine in standard ISO smoking mode and ISO Intense are presented. A significant decrease in the content of carbon monoxide, benzene and 1,3-butadiene in stick aerosols according to the ISO Intense and ISO modes was found. The amount of carbon monoxide produced in the effluent AGPh is 2% of its content in the AGPh of 3R4F control cigarettes, which confirms the absence of thermal decomposition (pyrolysis) of tobacco. It was determined that the AGPh of verses contains significantly fewer harmful and potentially dangerous compounds. A decrease in the content of benzene and 1,3-butadiene was found by more than 99% compared to the control sample of 3R4F cigarettes and five brands of cigarettes popular in Russia.

Laboratory measurements of gas‐phase reactions of polyatomic carbon ions C+n(n=1–6) and CnH+(n=2–5) with carbon monoxide

1987 ◽  
Vol 87 (12) ◽  
pp. 6934-6938 ◽  
Author(s):  
Diethard K. Bohme ◽  
Stanisl/aw Wl/odek ◽  
Leslie Williams ◽  
Leonard Forte ◽  
Arnold Fox
Keyword(s):  
Carbon Monoxide ◽  
Gas Phase ◽  
Carbon Ions ◽  
Laboratory Measurements ◽  
Gas Phase Reactions

scholarly journals Hydroxyl, water, ammonia, carbon monoxide and neutral carbon towards the Sgr A complex

2013 ◽  
Vol 9 (S303) ◽  
pp. 97-99
Author(s):  
R. Karlsson ◽  
Aa. Sandqvist ◽  
Å. Hjalmarson ◽  
A. Winnberg ◽  
K. Fathi ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
High Temperature ◽  
Open Access ◽  
Gas Phase ◽  
Combined Action ◽  
Circumnuclear Disk ◽  
Sgr A ◽  
Grain Surface ◽  
Very High ◽  
High Temperature Gas

AbstractWe observed Hydroxyl, water, ammonia, carbon monoxide and neutral carbon towards the +50 km s−1 cloud (M−0.02−0.07), the circumnuclear disk (CND) and the +20 km s−1 (M−0.13−0.08) cloud in the Sgr A complex with the VLA, Odin and SEST. Strong OH absorption, H2O emission and absorption lines were seen at all three positions. Strong C18O emissions were seen towards the +50 and +20 km s−1 clouds. The CND is rich in H2O and OH, and these abundances are considerably higher than in the surrounding clouds, indicating that shocks, star formation and clump collisions prevail in those objects. A comparison with the literature reveals that it is likely that PDR chemistry including grain surface reactions, and perhaps also the influences of shocks has led to the observed abundances of the observed molecular species studied here. In the redward high-velocity line wings of both the +50 and +20 km s−1 clouds and the CND, the very high H2O abundances are suggested to be caused by the combined action of shock desorption from icy grain mantles and high-temperature, gas-phase shock chemistry. Only three of the molecules are briefly discussed here. For OH and H2O three of the nine observed positions are shown, while a map of the C18O emission is provided. An extensive paper was recently published with Open Access (Karlsson et al. 2013, A&A 554, A141).

The gas-phase photochemistry and thermal decomposition of glyoxylic acid

1985 ◽  
Vol 63 (2) ◽  
pp. 542-548 ◽  
Author(s):  
R. A. Back ◽  
S. Yamamoto
Keyword(s):  
Thermal Decomposition ◽  
Carbon Monoxide ◽  
Absorption Spectrum ◽  
Gas Phase ◽  
Singlet State ◽  
Glyoxylic Acid ◽  
Static System ◽  
First Order ◽  
Increasing Temperature ◽  
Homogeneous Formation

The photolysis of glyoxylic acid vapour has been studied at five wavelengths, 382, 366, 346, 275, and 239 nm, and pressures from about 1 to 6 Torr, at a temperature of 355 K. Major products were CO2 and CH2O, initially formed in almost equal amounts, while minor products were CO and H2. Except at 382 nm, the system was complicated by the rapid secondary photolysis of CH2O. Three primary processes are suggested, each involving internal H-atom transfer followed by dissociation.The absorption spectrum is reported and shows the three distinct absorption systems. A finely-structured spectrum from about 320 to 400 nm is attributed to a transition to the first excited π* ← n+ singlet state; a more diffuse absorption ranging from about 290 nm to a maximum at 239 nm is assigned to the π* ← n− state, while a much stronger absorption beginning below 230 nm is attributed to the π* ← π transition. Product ratios vary with wavelength and depend on which excited state is involved.The thermal decomposition was studied briefly in a static system at temperatures from 470 to 710 K and pressures from 0.4 to 8 Torr. Major products were again CO2 and CH2O, but the latter was always less than stoichiometric. First-order rate constants for the apparently homogeneous formation of CO2 are described by Arrhenius parameters log A (s−1) = 7.80 and E = 30.8 kcal/mol. Carbon monoxide and H2 were minor products, and the CO/CO2 ratio increased with increasing temperature and showed some surface enhancement at lower temperatures. The SF6-sensitized thermal decomposition of glyoxylic acid, induced by a pulsed CO2 laser, was briefly studied, with temperatures estimated to be in the 1100–1600 K range, and the CO/CO2 ratio increased with increasing temperature, continuing the trend observed in the static system.

Catalysis by hydrogen halides in the gas phase. XVIII. Methyl formate and hydrogen bromide

1968 ◽  
Vol 21 (7) ◽  
pp. 1711
Author(s):  
DA Kairaitis ◽  
VR Stimson
Keyword(s):  
Carbon Monoxide ◽  
Gas Phase ◽  
Decomposition Product ◽  
Methyl Formate ◽  
Arrhenius Equation ◽  
Hydrogen Bromide ◽  
Radical Chain ◽  
Hydrogen Halides ◽  
Chain Decomposition ◽  
First Order

Hydrogen bromide catalyses the decomposition of methyl formate into carbon monoxide and methanol at 390-460�. The radical chain decomposition product, methane, is formed in only a small amount that is further reduced by the addition of inhibitor. The reaction is homogeneous and molecular, is first order in each reactant, and follows the Arrhenius equation: k2 = 1012.50exp(-32200/RT)sec-1 ml mole-1 It is not reversed by added methanol.

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