An Investigation into the Causes of the Aging Phenomena of Self‐Quenching Geiger‐Müller Counter Tubes; C2H5CN a Better Quench Gas than C2H5OH

In this paper, the aging effect of commercially available Geiger-Muller counters under working conditions is being considered from both theoretical and experimental point of view. In the experimental part lifetime curves for the commercial Geiger-Muller counter chamber are first recorded. After detection of the aging phenomena, the commercial chamber response to an impulse voltage is tested along with recording of the same response of the Geiger-Muller chamber model with conductive particles included. The law of similarity for the gaseous discharge is fulfilled both by the commercial Geiger-Muller chamber and by the chamber model with conductive particles. The results obtained from the U-test indicate that the aging of the Geiger-Muller chamber is mainly caused by the occurrence of a great number of conductive particles hovering inside the chamber. Some suggestions of how to reduce the aging effect due to conductive particles inside the Geiger-Muller chamber are given in the conclusion.

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Artificial Radioactivity

10.1093/oso/9780198827870.003.0011 ◽

2018 ◽

Author(s):

Roger H. Stuewer

Keyword(s):

Radioactive Isotope ◽

Alpha Particles ◽

Enrico Fermi ◽

Marie Curie ◽

Artificial Radioactivity ◽

Geiger Muller Counter

Frédéric Joliot discovered artificial radioactivity on January 11, 1934, when he bombarded aluminum with polonium alpha particles and produced a radioactive isotope of phosphorus that decayed by emitting a positron. He detected it with a Geiger–Müller counter that Wolfgang Gentner had constructed for him. Two months later, Enrico Fermi, motivated in part by an insight of his first assistant, Gian Carlo Wick, decided to see if neutrons also could produce artificial radioactivity. The transformation of a neutron into a proton in a nucleus should create an electron, so to increase their number and hence the probability of creating an electron, he bombarded various elements with intense sources of neutrons, and on March 20, 1934, with aluminum he observed the created electrons and thereby discovered neutron-induced artificial radioactivity. Less than four months later, Marie Curie died on July 4, 1934, at age sixty-six.

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Efficiency of the Geiger-Müller Counter

Nature ◽

10.1038/130699a0 ◽

1932 ◽

Vol 130 (3288) ◽

pp. 699-699 ◽

Cited By ~ 1

Author(s):

BRUNO ROSSI

Keyword(s):

Geiger Muller Counter

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Fracture Behavior of Ceramics Used in Multilayer Capacitors

MRS Proceedings ◽

10.1557/proc-72-81 ◽

1986 ◽

Vol 72 ◽

Cited By ~ 6

Author(s):

Theresa L. Baker ◽

Stephen W. Freiman

Keyword(s):

Crack Growth ◽

Fracture Behavior ◽

Ceramic Materials ◽

Fatigue Tests ◽

Internal Stresses ◽

Crack Growth Behavior ◽

Multilayer Capacitors ◽

Materials Used ◽

Aging Phenomena

AbstractThis study involved the determination of the effects of composition and microstructure on the fracture toughness and susceptibility to environmentally enhanced crack growth of several ceramic materials used in multilayer capacitors. Indentation-fracture procedures were used to measure KIC as well as to assess the possible effects of internal stresses on the fracture behavior of these materials and to correlate dielectric aging phenomena with strength. The environmentally enhanced crack growth behavior of these materials was determined by conducting dynamic fatigue tests in water.

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Thermal Aging Phenomena in Cast Duplex Stainless Steels

JOM ◽

10.1007/s11837-015-1709-9 ◽

2015 ◽

Vol 68 (2) ◽

pp. 507-516 ◽

Cited By ~ 25

Author(s):

T. S. Byun ◽

Y. Yang ◽

N. R. Overman ◽

J. T. Busby

Keyword(s):

Stainless Steels ◽

Thermal Aging ◽

Duplex Stainless Steels ◽

Aging Phenomena

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Application of Small Punch Test to Evaluate Tensile Properties of SA213T22 Grade Boiler Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.830-831.191 ◽

2015 ◽

Vol 830-831 ◽

pp. 191-194

Author(s):

M. Venkateswara Rao

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Tensile Properties ◽

Test Methods ◽

Uniaxial Tensile ◽

Test Results ◽

Small Punch Test ◽

Small Punch ◽

Punch Test ◽

Aging Phenomena

Conventional tensile test methods are used for service exposed high temperature boiler tubes to evaluate the deterioration in mechanical properties such as tensile strength, yield strength and percentage elongation. The mechanical properties are required to be evaluated periodically as the boiler components undergo material degradation due to aging phenomena. The aging phenomena occurs due to continuous exposure of tubes to high temperature & pressure steam prevailing inside the tubes and high temperature exposure to corrosive combustible gases from the external surfaces within the boiler.A recent developed new technique called small punch testing has been used to evaluate the tensile properties of SA 213T22 grade steel predominantly exists in super-heater and re-heater sections of boiler. The small punch tests have been carried out on the miniature disk shaped specimens of diameter of 8.0 mm and 0.5 mm thickness extracted from both the new and service exposed tubes. Conventional uniaxial tensile tests on standard specimens from the same tube material have also been performed for comparison. The service exposed tubes showed considerable loss in mechanical properties in both the conventional and small punch test results. Correlations of tensile properties have been obtained based on the comparative analysis of both small punch and uniaxial tensile test results. Further, the study showed that an appropriate empirical relation could be generated for new and service exposed materials between both the techniques. Conventional test methods require large quantity of material removal for test samples from in-service components whereas small punch test method needs only a miniature sample extraction. This small punch test technique could also be extended to evaluate the thicker section boiler components such as pipelines and headers in the boiler as a part of remaining life assessment study. Also this technique could be a useful tool to any metallic component where large quantity of sample removal may be difficult or may not be feasible.

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