THE ADSORPTION AND REPLACEMENT OF HYDROGEN ON POLYCRYSTALLINE TUNGSTEN

1965 ◽  
Vol 43 (6) ◽  
pp. 1020-1035 ◽  
Author(s):  
L. J. Rlgby
Keyword(s):  
Carbon Monoxide ◽  
Second Order ◽  
Tungsten Filament ◽  
Α Phase ◽  
Polycrystalline Tungsten

Desorption spectra have been obtained which show that there are at least three β phases of hydrogen desorbed from a tungsten filament. The β2 phase was desorbed with second-order kinetics. The replacement of hydrogen by nitrogen and by carbon monoxide was observed, and simple replacement mechanisms are proposed for these processes and the replacement of carbon monoxide by nitrogen. When carbon was preadsorbed on the surface, the β1 phase of hydrogen and all the β phases of carbon monoxide and nitrogen were reduced, but the α phase of carbon monoxide was increased. A concept of identical and nonidentical sites is introduced to explain these results.

THE CHEMISORPTION OF NITROGEN ON POLYCRYSTALLIN TUNGSTEN WIRES

1965 ◽  
Vol 43 (4) ◽  
pp. 532-546 ◽  
Author(s):  
L. J. Rigby
Keyword(s):  
Activation Energy ◽  
Room Temperature ◽  
Second Order ◽  
Mass Spectrometric ◽  
Kcal Mole ◽  
First Order ◽  
First Order Kinetics ◽  
Α Phase ◽  
Polycrystalline Tungsten ◽  
Mass Spectrometric Evidence

Desorption spectra have been obtained for successively increasing amounts of nitrogen adsorbed on three polycrystalline tungsten wires at room temperature. Two β phases were desorbed, β1 with first-order kinetics and an activation energy of 73 kcal/mole and β2with second-order kinetics and an activation energy of 75 kcal/mole. Surface impurities such as carbon or thorium reduced the size of the β1 phase. Mass spectrometric evidence showed that the small α phase was adsorbed as molecules, and the β1 and β2 phases were adsorbed as atoms.

THE INTERACTIONS OF NITROGEN AND CARBON MONOXIDE ON POLYCRYSTALLINE TUNGSTEN

1964 ◽  
Vol 42 (6) ◽  
pp. 1256-1269 ◽  
Author(s):  
L. J. Rigby
Keyword(s):  
Carbon Monoxide ◽  
Mass Spectrometer ◽  
Tungsten Wire ◽  
Activation Energies ◽  
Β Phase ◽  
Polycrystalline Tungsten

Desorption spectra from a polycrystalline tungsten wire have been obtained with a mass spectrometer to study: (a) the effect of preadsorbed nitrogen on the adsorption of carbon monoxide; (b) the reversibility and rearrangement of the carbon monoxide monolayer; and (c) the slow replacement of carbon monoxide by nitrogen. Surface coverages have been measured, and the activation energies of desorption obtained for all phases of carbon monoxide and the β phase of nitrogen.

CO2 Laser-induced and BCl3-sensitized decomposition of hexafluoroacetone. Comparison with high temperature thermochemistry

1982 ◽  
Vol 47 (3) ◽  
pp. 912-917
Author(s):  
Josef Pola ◽  
Pavel Engst ◽  
Milan Horák
Keyword(s):  
Thermal Decomposition ◽  
Carbon Monoxide ◽  
High Temperature ◽  
Co2 Laser ◽  
Carbonyl Compounds ◽  
Total Pressure ◽  
Tungsten Filament ◽  
Reaction Progress ◽  
Induced Decomposition ◽  
Carbonyl Fluoride

The cw CO2laser-induced decomposition of hexafluoroacetone sensitized with boron trichloride (total pressure 5.3-8.0 kPa) yields along with perfluorinated hydrocarbons trifluoroacetyl fluoride, carbon monoxide and carbonyl fluoride. The same carbonyl compounds are also formed by conventional thermal decomposition of hexafluoroacetone on tungsten filament at temperatures 950-2 100°C but their distribution during reaction progress is different. Features of both reactions are discussed.

Adsorption and Decomposition of Ammonia on a Polycrystalline Tungsten Filament

1970 ◽  
Vol 52 (9) ◽  
pp. 4877-4889 ◽  
Author(s):  
Kun‐Ichi Matsushita ◽  
Robert S. Hansen
Keyword(s):  
Tungsten Filament ◽  
Polycrystalline Tungsten

The kinetics and mechanism of the reactions between carbon monoxide and ruthenium(II) chlorides in solution

1970 ◽  
Vol 48 (23) ◽  
pp. 3613-3618 ◽  
Author(s):  
B. C. Hui ◽  
B. R. James
Keyword(s):  
Carbon Monoxide ◽  
Molecular Nitrogen ◽  
Second Order ◽  
Kinetics And Mechanism ◽  
Gas Uptake ◽  
First Order ◽  
Kinetics Of Formation ◽  
Low Pressures ◽  
Kinetics Of ◽  
Hcl Solution

The kinetics of formation of mono- and dicarbonyl complexes in two successive stages by direct carbonylation of ruthenium(II) chlorides in dimethylacetamide solution have been studied at 65–80° and up to 1 atm CO by gas uptake techniques. Both stages are first order in ruthenium. Formation of the monocarbonyl is independent of CO pressure; dicarbonyl formation is first order in CO at low pressures with the order decreasing towards zero with increasing pressure, and shows an inverse chloride dependence from 0.1–2.0 M added chloride. For both stages, the data are consistent with a mechanism involving predissociation. A similar mechanism is suggested for the corresponding reactions in 3 M HCl solution which had been studied earlier and which showed overall second-order kinetics.Discussion on the related formation of molecular nitrogen complexes of ruthenium(II) is presented.

scholarly journals On a new effect in the electric discharge

1928 ◽  
Vol 117 (778) ◽  
pp. 542-549 ◽  
Keyword(s):  
Carbon Monoxide ◽  
Magnetic Fields ◽  
Electric Discharge ◽  
Tungsten Filament ◽  
Streamer Discharge ◽  
Current Discharge ◽  
Weak Magnetic Fields ◽  
The Subject ◽  
Vacuum Tubes ◽  
Low Pressures

There are a number of spectra which are seen under appropriate conditions of excitation in vacuum tubes containing helium with a small trace of some other gas, but which are difficult to isolate under other conditions. In particular the arc spectrum of carbon and the band spectrum known as the comet tail spectrum can be observed very favourably under these conditions. This latter spectrum, which is characteristic of the tails of comets, was first observed in the laboratory by Fowler in carbon monoxide at very low pressures, and recent analyses of the spectrum leave no doubt that it is to be attributed to the carbon monoxide molecule. In the course of the investigation of this spectrum in vacuum tubes containing helium some very peculiar types of striated discharge were observed, and further investigation leads to the conclusion that these striae are of a very special type and are quite different to those which are usually observed in vacuum tubes. They exhibit certain peculiarities which may perhaps justify the suggestion that this type of discharge is akin to the rare phenomenon known as ball lightning. The striae usually observed in vacuum tubes may be classified as stationary and moving striæ. The former have been observed since the earliest investigations of the electric discharge in gases at low pressures, and their appearance and behaviour is so well known as to need no description. The moving striations, first observed by Wullner, have recently been the subject of more critical investigations by Aston and Kikuchi and Whiddington, who by the application of stroboscopic methods have observed in pure gases striations moving with velocities of from 10 3 to 10 6 cm. per second. More recently Langmuir has described a peculiar type of streamer discharge which he has observed in argon containing a small amount of tungsten vapour which was introduced by the sputtering of a tungsten filament. Whilst the phenomena described by Langmuir bear a certain resemblance to those described in the present communication, inasmuch as in both cases the formation of a particulate cloud has been observed, the conditions of experiment are so different as to make it almost certain that the phenomena are different in origin. Langmuir’s observations were made with a direct current discharge, using an electrically heated tungsten filament as the cathode, and the streamer discharge observed by him was very sensitive to weak magnetic fields, whilst the disc discharge which has been the subject of the present investigation can only be maintained with an alternating current discharge, and is entirely unaffected by weak magnetic fields.

scholarly journals FREQUENCY RESPONSE OF NORRIS GAP DERIVATIVES AND ITS PROSPERITIES FOR GAS SPECTRA ANALYSIS

2020 ◽  
Vol 10 (4) ◽  
pp. 25-28
Author(s):  
Sławomir Cięszczyk
Keyword(s):  
Carbon Monoxide ◽  
Numerical Methods ◽  
Frequency Response ◽  
Optical Spectra ◽  
Frequency Characteristics ◽  
Second Order ◽  
Impulse Responses ◽  
Low Resolution ◽  
Spectra Analysis ◽  
Frequency Responses

The article deals with an analysis of the properties of Norris gap derivatives. It discusses issues related to determining information from optical spectra measured with spectrometers. Impulse responses of differentiating filters were introduced using both Norris and Savitzky-Golay methods. The amplitude-frequency responses of the first and second order Norris differentiating filters were compared. The length impact of both segment and gaps on the frequency characteristics of filters was compared. The processing of exemplary gas spectra using the discussed technique was subsequently presented. The effect of first and second order derivatives on the spectra of carbon monoxide rotational lines for low resolution measurements is investigated. The Norris method of derivatives are very simple to implement and the calculation of their parameters does not require the use of advanced numerical methods.

Thermal desorption: Chemisorption of carbon monoxide on polycrystalline tungsten

1982 ◽  
Vol 47 (3) ◽  
pp. 884-890 ◽  
Author(s):  
Jan Hrbek ◽  
Jan Pavlíček
Keyword(s):  
Carbon Monoxide ◽  
Adsorption Isotherm ◽  
Thermal Desorption ◽  
Dissociative Adsorption ◽  
Experimental Results ◽  
Polycrystalline Tungsten

The adsorption isotherm was constructed from thermal desorption spectra of carbon monoxide on tungsten. Comparison of the experimental results with model isotherms supports a concept of the dissociative adsorption of carbon monoxide on tungsten.

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