A determination of W and G(H2) values for methyl fluoride and fluoroform

Mario Saca; R. A. Lee

doi:10.1139/v70-300

A determination of W and G(H2) values for methyl fluoride and fluoroform

Canadian Journal of Chemistry ◽

10.1139/v70-300 ◽

1970 ◽

Vol 48 (12) ◽

pp. 1812-1814 ◽

Cited By ~ 1

Author(s):

Mario Saca ◽

R. A. Lee

Keyword(s):

Gamma Rays ◽

Ionization Chamber ◽

Parallel Plate ◽

Ion Pair ◽

Methyl Fluoride ◽

Gray Theory ◽

Plate Type

Methyl fluoride and fluoroform have been irradiated with gamma rays from a 1200-Ci 60Co source. Ionization currents were measured using a Pyrex parallel-plate-type ionization chamber. W values of 27.2 and 28.0 eV were determined for the two gases, CH3F and CHF3, respectively. The method employed was a comparative one, making use of the Bragg–Gray theory of cavity ionization. G(H2) yields of 4.20 and 1.25 for CH3F and CHF3, respectively, were then calculated from the above W values and the measured ion-pair yields for hydrogen. The formation of hydrogen is probably due to the fact that the C—H bonds in these compounds are weaker than the C—F bonds.

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Determination of absorbed dose to water from a miniature kilovoltage x-ray source using a parallel-plate ionization chamber

Physics in Medicine and Biology ◽

10.1088/1361-6560/aa9560 ◽

2017 ◽

Vol 63 (1) ◽

pp. 015016 ◽

Cited By ~ 15

Author(s):

Peter G F Watson ◽

Marija Popovic ◽

Jan Seuntjens

Keyword(s):

Ionization Chamber ◽

Parallel Plate ◽

Absorbed Dose ◽

X Ray ◽

Absorbed Dose To Water

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A NEW METHOD FOR THE REDUCTION OF ALPHA-RAY BACKGROUND IN A GRIDDED IONIZATION CHAMBER

Canadian Journal of Physics ◽

10.1139/p62-062 ◽

1962 ◽

Vol 40 (5) ◽

pp. 607-621 ◽

Cited By ~ 14

Author(s):

Tadayoshi Doke

Keyword(s):

Ionization Chamber ◽

Present Method ◽

Parallel Plate ◽

Alpha Particles ◽

Operating Conditions ◽

Good Resolution ◽

Practical Applications ◽

Weak Activity ◽

Background Counting ◽

Plate Type

By making use of grid pulses in a double-gridded ionization chamber, it was attempted to eliminate the background pulses caused by the alpha particles emitted from electrodes other than the cathode. Operating conditions for the reductions of the background in this method were investigated analytically. Using the double-gridded chamber of a parallel-plate type with a maximum sample area of 80 cm2 for alpha particles of 9 Mev, a background counting rate of one count per hour was achieved in the energy region from 3.5 to 9 Mev. It was found that an insulator like polyethylene could be used as a sample base with a good resolution for very weak activity. Spectra of weak alpha activities were measured by the present method. For the purpose of practical applications, the construction of a cylindrical double-gridded chamber is proposed.

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XVII.—The Ionizing Efficiency of Electronic Impacts in Air

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s0370164600023075 ◽

1932 ◽

Vol 51 ◽

pp. 127-141 ◽

Cited By ~ 3

Author(s):

John Thomson

Keyword(s):

Ionization Chamber ◽

Ion Pair ◽

Initial Speed ◽

Total Ionization

SummaryExperiments are described, the aim of which is the determination of the energy spent in producing one pair of ions when electrons of velocity corresponding to 50–270 volts are totally absorbed in air. It is found that this energy varies with the initial speed of the electron, but that it asymptotes to the value 37 ± 2 electron-volts when the energy of the electron is very great.This value of the “volts per ion pair” is compared with those found by other experimenters. A correlation of the three electronic “constants,” the range of the electron, the ionization per unit path, and the total ionization is attempted. It is concluded that, unless in the case of very fast cathode rays or β-particles, the “ionization per unit path,” as measured by ionization chamber experiments, has no meaning.

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A Calorimetric Determination of the Energy Required to Produce an Ion Pair in Air for Cobalt-60 Gamma-Rays

Radiation Research ◽

10.2307/3570582 ◽

1956 ◽

Vol 5 (6) ◽

pp. 613 ◽

Cited By ~ 15

Author(s):

J. P. Bernier ◽

L. D. Skarsgard ◽

D. V. Cormack ◽

H. E. Johns

Keyword(s):

Gamma Rays ◽

Ion Pair ◽

Calorimetric Determination

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Determination of the quality factor in a mixed field of gamma-rays and neutrons by an ionization chamber filled with a dielectric liquid, II

Nuclear Instruments and Methods ◽

10.1016/0029-554x(67)91333-x ◽

1967 ◽

Vol 53 ◽

pp. 71-76 ◽

Cited By ~ 4

Author(s):

M. Ladu ◽

M. Pelliccioni ◽

M. Roccella

Keyword(s):

Quality Factor ◽

Gamma Rays ◽

Ionization Chamber ◽

Dielectric Liquid ◽

Mixed Field

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Systematic procedure for the determination of the nature of the solutes prior to the selection of the mobile phase parameters for optimization of reversed-phase ion-pair chromatographic separations

Journal of Chromatography A ◽

10.1016/s0021-9673(01)84371-5 ◽

1989 ◽

Vol 478 (1) ◽

pp. 21-38 ◽

Cited By ~ 1

Author(s):

G Low

Keyword(s):

Mobile Phase ◽

Reversed Phase ◽

Ion Pair ◽

Chromatographic Separations ◽

Systematic Procedure ◽

Selection Of

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Extractive Spectrophotometric Method for the Determination of Glibenclamide by Ion-Pair Complex in Pure Form and Pharmaceutical Formulation

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v9i3.20 ◽

2019 ◽

Vol 9 (o3) ◽

Author(s):

RUAA MUAYAD MAHMOOD ◽

HAMSA MUNAM YASSEN ◽

SAMAR , NAJWA ISSAC ABDULLA AHMED DARWEESH ◽

NAJWA ISSAC ABDULLA

Keyword(s):

Spectrophotometric Method ◽

Molar Absorptivity ◽

Ion Pair ◽

Pharmaceutical Formulation ◽

Ratio Method ◽

Colored Complex ◽

Colored Product ◽

Method Of Continuous Variation ◽

Job's Method

Simple, rapid and sensitive extractive spectrophotometric method is presented for the determination of glibenclamide (Glb) based on the formation of ion-pair complex between the Glb and anionic dye, methyl orange (MO) at pH 4. The yellow colored complex formed was quantitatively extracted into dichloromethane and measured at 426 nm. The colored product obeyed Beer’s law in the concentration range of (0.5-40) μg.ml-1. The value of molar absorptivity obtained from Beer’s data was found to be 31122 L.mol-1.cm-1, Sandell’s sensitivity value was calculated to be 0.0159 μg.cm-2, while the limits of detection (LOD) and quantification (LOQ) were found to be 0.1086 and 0.3292 μg.ml-1, respectively. The stoichiometry of the complex created between the Glb and MO was 1:1 as determined via Job’s method of continuous variation and mole ratio method. The method was successfully applied for the analysis of pharmaceutical formulation.

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