THE REACTION OF ISOPROPANOL VAPOR WITH Hg 6(3P1) ATOMS: PART II: REACTION IN THE PRESENCE OF NITRIC OXIDE

1963 ◽  
Vol 41 (3) ◽  
pp. 763-769 ◽  
Author(s):  
Arthur R. Knight ◽  
Harry E. Gunning
Keyword(s):  
Nitric Oxide ◽  
Room Temperature ◽  
High Pressures ◽  
New Products ◽  
Reaction Vessel ◽  
Inert Gas ◽  
Primary Process ◽  
Static System ◽  
Carbon Tetrafluoride ◽  
Dark Reaction

The reaction of isopropanol vapor with Hg 6(3P1) atoms in the presence of nitric oxide has been investigated in a static system at room temperature as a function of exposure time. In addition to the major products hydrogen, pinacol, and acetone found in the pure substrate reaction, the new products isopropyl nitrite, nitrous oxide, and nitrogen were observed. The effect on the reaction of the inert gas carbon tetrafluoride was also studied.Evidence is adduced for the production of excited isopropoxy radicals in the primary process, and the rise in the nitrite and acetone yields, observed upon increasing the added inert gas pressure, is ascribed to quenching of these excited species.The nitrite produced in the decomposition of Me2CDOH was found to be ca. 98% Me2CDONO, dictating its formation from the isopropoxy radical and not from Me2COH.A nitrite-producing dark reaction was observed when high pressures of CF4 were added and the reaction could be prevented only by measures designed to exclude trace quantities of NO2 from the reaction vessel.

Fluorescence and vibrational relaxation of nitric oxide studied by kinetic spectroscopy

1961 ◽  
Vol 260 (1303) ◽  
pp. 459-474 ◽  
Keyword(s):  
Nitric Oxide ◽  
Vibrational Relaxation ◽  
High Pressures ◽  
Flash Photolysis ◽  
Electronic States ◽  
Analytic Form ◽  
Gas Mixtures ◽  
Inert Gas ◽  
Flash Duration ◽  
Kinetic Spectroscopy

The first excited vibrational level of the ground electronic states of nitric oxide was popu­lated above its equilibrium value by flash photolysis of nitric oxide + inert gas mixtures, under isothermal conditions. Electronic excitation NO 2 II ( v = 0) + hv → NO 2 Ʃ ( v = 0, 1, 2) was followed either by fluorescence NO 2 Ʃ ( v = 0, 1, 2) → NO 2 II ( v = 0, 1, 2...) + hv , or by quenching NO 2 Ʃ ( v = 0, 1, 2) + M → NO 2 II( v = 0, 1, 2...) + M , causing a non-equilibrium population of the vibrational levels of the ground electronic states. Subsequently, the reactions NO 2 II ( v = 1) + M → NO 2 II ( v = 0) + M and NO 2 II ( v = 1) + NO 2 II ( v = 0) → 2NO 2 II ( v = 1) caused a decay of the vibrationally excited molecules with time; this was followed in absorption by kinetic spectroscopy. Because of the rapidity of the last reaction, bands of NO2 II with v >1 were usually observed only in the fluorescence spectrum. In mixtures of 1 to 5 mm of NO with a large excess of nitrogen or krypton, the con­centration of NO2 II ( v = 1) produced by the flash was of the order of 10-1 mm pressure, i. e. about the same concentration which is present in one atmosphere pressure of NO at room temperature. The absolute concentration of NO2 II ( v = 1) was measured accurately by plate photometry, high pressures of NO being used for calibration. The recorded probabilities of vibrational relaxation, P1-0, for NO2 II ( v = 1), and radii for electronic quenching, σ e , by NO, N 2 , CO, H 2 O and CO 2 , are P 1-0 σ e (Å) NO 3.55 x 10 -4 14 N 2 4 x 10 -7 ≤ 2x 10 -2 CO 2.5 x 10 -5 0.6 H 2 O 7 x 10 -3 30 CO 2 1.7 x 10 -4 5 With the use of an analytic form for the flash duration, the entire rise and fall of the concentration of excited species was quantitatively interpreted. A very small fraction of the NO was decomposed by the flash, due either to absorption of radiation below 1900 Å or by reaction of metastable NO molecules with each other or with ground state molecules. Abnormal effects were observed in NO+ H 2 +inert gas mixtures and chemical reaction occurred.

PRELIMINARY STUDY OF PHOTOCHEMICAL BEHAVIOR IN THE SYSTEM NITROGEN DIOXIDE – ETHANE

1955 ◽  
Vol 33 (5) ◽  
pp. 843-848
Author(s):  
T. M. Rohr ◽  
W. Albert Noyes Jr.
Keyword(s):  
Nitric Oxide ◽  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Nitrogen Dioxide ◽  
Room Temperature ◽  
Reverse Reaction ◽  
Primary Process ◽  
Photochemical Behavior ◽  
Preliminary Study ◽  
Oxygen Atoms

The addition of ethane to nitrogen dioxide either during exposure to radiation transmitted by pyrex, or afterwards, reduces the amount of oxygen formed. At room temperature this is apparently due to the effectiveness of ethane in promoting the reverse reaction of nitric oxide and oxygen to form nitrogen dioxide. At temperatures over 100° there is a reaction which uses oxygen atoms produced in the primary process. Nitroethane (or nitrosoethane) is formed along with carbon monoxide, carbon dioxide, and some methane. The results suggest that acetaldehyde is an intermediate, but acetaldehyde could not be detected because it would react thermally with nitrogen dioxide. It is not possible to give a complete explanation of the results, but suggestions can be made which might form the basis for later work.

scholarly journals THE REACTIONS OF ELECTRONICALLY EXCITED NITRIC OXIDE MOLECULES WITH HYDROCARBONS

1963 ◽  
Vol 41 (5) ◽  
pp. 1207-1222 ◽  
Author(s):  
O. P. Strausz ◽  
H. E. Gunning
Keyword(s):  
Nitric Oxide ◽  
Room Temperature ◽  
Circulatory System ◽  
Average Chain Length ◽  
Primary Process ◽  
Reaction Products ◽  
Electronically Excited ◽  
Yield Values ◽  
Methyl Nitrate ◽  
Ethyl Nitrite

The reactions of NO(4II) molecules, generated by Hg 6(3P1) photosensitization, with methane, ethane, propane, neopentane, and benzene have been studied at room temperature in a circulatory system. In the case of ethane the following reaction products were identified: N2, N2O, H2O, NO2, CO, CO2, C2H4, acetaldehyde, nitroethane, ethyl nitrite, ethyl nitrate, nitroethylene, nitromethane, methyl nitrite, methyl nitrate, formaldehyde. For hydrocarbon consumption, under comparable conditions, the following quantum yield values were established: [Formula: see text]. The most probable primary process may be represented by the sequence[Formula: see text] [Formula: see text]Alkyl free radicals catalyze the chain disproportionation of nitric oxide at room temperature according to the stoichiometric equation[Formula: see text]A minimal value of 12 was established for the average chain length.

Line mixing in the nitric oxide R-branch near 5.2 μm at high pressures and temperatures: Measurements and empirical modeling using energy gap fitting

2021 ◽  
Vol 276 ◽  
pp. 107935
Author(s):  
Christopher A. Almodovar ◽  
Wey-Wey Su ◽  
Rishav Choudhary ◽  
Jiankun Shao ◽  
Christopher L. Strand ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
High Pressures ◽  
Energy Gap ◽  
Empirical Modeling ◽  
Line Mixing ◽  
High Pressures And Temperatures

Effects of acetone in heparin on the multiple inert gas elimination technique

1985 ◽  
Vol 58 (4) ◽  
pp. 1143-1147 ◽  
Author(s):  
F. L. Powell ◽  
F. A. Lopez ◽  
P. D. Wagner
Keyword(s):  
Partial Pressure ◽  
Dead Space ◽  
Room Temperature ◽  
Inert Gas ◽  
Published Data ◽  
Physiological Mechanisms ◽  
Heparinized Saline ◽  
Partial Pressures ◽  
Ventilation Perfusion Ratio ◽  
Mixed Venous

We have detected acetone in several brands of heparin. If uncorrected, this leads to errors in measuring acetone in blood collected in heparinized syringes, as in the multiple inert gas elimination technique for measuring ventilation-perfusion ratio (VA/Q) distributions. Error for acetone retention [R = arterial partial pressure-to-mixed venous partial pressure (P-V) ratio] is usually small, because R is normally near 1.0, and the error is similar in arterial and mixed venous samples. However, acetone excretion [E = mixed expired partial pressure (P-E)-to-P-V ratio] will appear erroneously low, because P-E is accurately measured in dry syringes, but P-V is overestimated. A physical model of a homogeneous alveolar lung at room temperature and without dead space shows: the magnitude of acetone E error depends upon the ratio of blood sample to heparinized saline volumes and acetone partial pressures, without correction, acetone E can be less than that of less soluble gases like ether, a situation incompatible with conventional gas exchange theory, and acetone R and E can be correctly calculated using the principle of mass balance if the acetone partial pressure in heparinized saline is known. Published data from multiple inert gas elimination experiments with acetone-free heparin, in our labs and others, are within the limits of experimental error. Thus the hypothesis that acetone E is anomalously low because of physiological mechanisms involving dead space tissue capacitance for acetone remains to be tested.

EFFECTIVE MAGNETIC ANISOTROPY AND COERCIVITY IN Fe NANOPARTICLES PREPARED BY INERT GAS CONDENSATION

2006 ◽  
Vol 20 (01) ◽  
pp. 37-47
Author(s):  
LUBNA RAFIQ SHAH ◽  
BAKHTYAR ALI ◽  
S. K. HASANAIN ◽  
A. MUMTAZ ◽  
C. BAKER ◽  
...  
Keyword(s):  
Room Temperature ◽  
Size Range ◽  
Magnetic Measurements ◽  
Uniaxial Anisotropy ◽  
Inert Gas ◽  
Condensation Process ◽  
Gas Condensation ◽  
Inert Gas Condensation ◽  
Fe Nanoparticles ◽  
Characterization Studies

We present magnetic measurements on iron ( Fe ) nanoparticles in the size range 10–30 nm produced by the Inert Gas Condensation process (IGC). Structural characterization studies show the presence of a core/shell structure, where the core is bcc Fe while the surface layer is Fe -oxide. Analysis of the magnetic measurements shows that the nanoparticles display very large uniaxial anisotropy, K eff ≈3 - 4 × 106 erg/cc. The observed room temperature coercivities lie in the range ≈600 – 973 Oe , much larger than those expected from the Stoner–Wohlfarth model using the bulk iron anisotropy. It can be inferred from the coercivity variation with the particle size that there is a general trend of the coercivity increasing with size, culminating finally in a decrease for high sizes (30 nm) possibly due to the onset of non-coherent magnetization reversal processes.

Gas-phase reactions of nitric oxide with atomic lanthanide cations: Room-temperature kinetics and periodicity in reactivity

2006 ◽  
Vol 249-250 ◽  
pp. 385-391 ◽  
Author(s):  
Voislav Blagojevic ◽  
Eric Flaim ◽  
Michael J.Y. Jarvis ◽  
Gregory K. Koyanagi ◽  
Diethard K. Bohme
Keyword(s):  
Nitric Oxide ◽  
Gas Phase ◽  
Room Temperature ◽  
Gas Phase Reactions ◽  
Lanthanide Cations

Melting of inert gas solids at high pressures

Cryogenics ◽  
1966 ◽  
Vol 6 (6) ◽  
pp. 372-373 ◽  
Author(s):  
S.N Vaidya ◽  
E.S.R Gopal
Keyword(s):  
High Pressures ◽  
Inert Gas

Basic procedures

1999 ◽  
Author(s):  
Weng C. Chan ◽  
Peter D. White
Keyword(s):  
Peptide Synthesis ◽  
Reaction Vessel ◽  
Inert Gas ◽  
Peptide Chain ◽  
Correct Method ◽  
Sintered Glass ◽  
The Subject ◽  
Gas Bubbling

A number of excellent descriptions of the techniques related to peptide chain assembly have already been published. These processes are also described in the operator manuals supplied by the peptide synthesis instrument manufacturers. Accordingly, the treatment of the subject presented here has been kept brief in order to provide more space in this volume for those topics not covered in detail in other publications of this type. The protocols have been written as they would be carried out using a manual peptide synthesis vessel. Whilst it is appreciated that most scientists preparing peptides will be using automated peptide synthesizers, it is not possible, given the wide variation in operating procedures, to describe how such methods may be applied to individual instruments. Particular emphasis has been given here to those operations which are typically carried out off-instrument, such as first residue attachment and peptide-resin cleavage. The operations described in this chapter can be carried out in a purpose-built peptide synthesis vessel or in a sintered glass funnel fitted with a three-way stopcock. The operation of the system is extremely simple: solvents are added from the top of the vessel, ensuring any resin adhering to the sides is rinsed down into the resin bed; the resin bed is agitated by setting the tap to position 1 to allow flow of nitrogen to the reaction vessel; solvents and reagents are removed by setting the tap to position 2 to connect the vessel to the vacuum. The use of such vessels has previously been described in detail. Peptide synthesis resins are extremely fragile and the beads, if wrongly handled, can easily fracture, leading to the generation of fines which can block reaction vessel filter-frits and solvent lines. It is particularly important that the correct method is used for mixing the resin and soluble reactants. Polystyrene-based supports are best agitated by bubbling an inert gas through the resin bed, or by shaking or vortexing the reaction vessel. Whilst all of these approaches are employed in commercial synthesizers, gas-bubbling and shaking are the most appropriate for use in manual synthesis.

scholarly journals Forming pressure effect on microstructure and mechanical properties of nanocrystalline aluminum synthesized by inert gas condensation

2019 ◽  
Vol 79 ◽  
pp. 02002
Author(s):  
Shangshu Wu ◽  
Zhou Yu ◽  
Junjie Wang ◽  
Hanxin Zhang ◽  
Chaoqun Pei ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Vacuum ◽  
Inert Gas ◽  
Helium Atmosphere ◽  
Gas Condensation ◽  
Inert Gas Condensation ◽  
In Situ Forming ◽  
Nanocrystalline Aluminum ◽  
Al Powder

The preparation of nanocrystalline aluminum (NC Al) was conducted in two steps. After the NC Al powder was synthesized by an Inert gas condensation (IGC) method in a helium atmosphere of 500 Pa, the NC Al powder was in-situ compacted into a pellet with a 10 mm diameter and 250 μm-300 μm thickness in a high vacuum (10-6 Pa-10-7 Pa) at room temperature. The NC Al samples were not exposed to air during the entire process. After the pressure reached 6 GPa, the relative density could reach 99.83%. The results showed that the grain size decreased with the increased of in-situ forming pressure. The NC Al samples present obvious ductile fracture, and the tensile properties were greatly changed with the increase of forming pressure.

Sign in / Sign up

Export Citation Format

Share Document