scholarly journals Statistical treatment of nuclear counting results

2011 ◽  
Vol 26 (2) ◽  
pp. 164-170 ◽  
Author(s):  
Cemal Dolicanin ◽  
Koviljka StankoviC ◽  
Diana Dolicanin ◽  
Boris Loncar
Keyword(s):  
Statistical Method ◽  
Nuclear Physics ◽  
Background Radiation ◽  
Statistical Treatment ◽  
Measurement Data ◽  
Radioactive Decay ◽  
Random Variables ◽  
Radioactive Source ◽  
Statistical Sample ◽  
Nuclear Counting

Since the exact time a specific nucleus undergoes radioactive decay cannot be specified, nor can showers caused by secondary cosmic rays be predicted, statistical laws play an important role in almost all cases of experimental nuclear physics. This paper describes the method for the statistical treatment of nuclear counting results obtained experimentally by taking into account random variables pertaining to both frequent and infrequent phenomena. When processing counting measurement data, it is recommended to first discard spurious random variables that spoil the statistics by using Chauvenet?s criterion, as well as to test if the results in the statistical sample follow a unique statistical distribution by using the Wilcoxon rank-sum test (U-test). The verification of the suggested statistical method was performed on counting statistics obtained both from the radioactive source Cs-137 and background radiation, expected to follow the normal distribution and the Poisson distribution, respectively. Results show that the application of the proposed statistical method excludes random fluctuations of the radioactive source or of the background radiation from the total statistical sample, as well as possible inadequacies in the experimental set-up and show an extremely effective agreement of the theoretical distribution of random variables with the corresponding experimentally obtained random variables.

scholarly journals Atmospheric removal times of the aerosol-bound radionuclides <sup>137</sup>Cs and <sup>131</sup>I measured after the Fukushima Dai-ichi nuclear accident – a constraint for air quality and climate models

2012 ◽  
Vol 12 (22) ◽  
pp. 10759-10769 ◽  
Author(s):  
N. I. Kristiansen ◽  
A. Stohl ◽  
G. Wotawa
Keyword(s):  
Air Quality ◽  
Dry Deposition ◽  
Nuclear Power ◽  
Climate Models ◽  
Climate Model ◽  
Noble Gas ◽  
Measurement Data ◽  
Radioactive Decay ◽  
Data Set ◽  
Removal Time

Abstract. Caesium-137 (137Cs) and iodine-131 (131I) are radionuclides of particular concern during nuclear accidents, because they are emitted in large amounts and are of significant health impact. 137Cs and 131I attach to the ambient accumulation-mode (AM) aerosols and share their fate as the aerosols are removed from the atmosphere by scavenging within clouds, precipitation and dry deposition. Here, we estimate their removal times from the atmosphere using a unique high-precision global measurement data set collected over several months after the accident at the Fukushima Dai-ichi nuclear power plant in March 2011. The noble gas xenon-133 (133Xe), also released during the accident, served as a passive tracer of air mass transport for determining the removal times of 137Cs and 131I via the decrease in the measured ratios 137Cs/133Xe and 131I/133Xe over time. After correction for radioactive decay, the 137Cs/133Xe ratios reflect the removal of aerosols by wet and dry deposition, whereas the 131I/133Xe ratios are also influenced by aerosol production from gaseous 131I. We find removal times for 137Cs of 10.0–13.9 days and for 131I of 17.1–24.2 days during April and May 2011. The removal time of 131I is longer due to the aerosol production from gaseous 131I, thus the removal time for 137Cs serves as a better estimate for aerosol lifetime. The removal time of 131I is of interest for semi-volatile species. We discuss possible caveats (e.g. late emissions, resuspension) that can affect the results, and compare the 137Cs removal times with observation-based and modeled aerosol lifetimes. Our 137Cs removal time of 10.0–13.9 days should be representative of a "background" AM aerosol well mixed in the extratropical Northern Hemisphere troposphere. It is expected that the lifetime of this vertically mixed background aerosol is longer than the lifetime of fresh AM aerosols directly emitted from surface sources. However, the substantial difference to the mean lifetimes of AM aerosols obtained from aerosol models, typically in the range of 3–7 days, warrants further research on the cause of this discrepancy. Too short modeled AM aerosol lifetimes would have serious implications for air quality and climate model predictions.

scholarly journals Applying al-zughair transform on nuclear physics

2020 ◽  
Vol 9 (1) ◽  
pp. 9
Author(s):  
Emad A. Kuffi ◽  
Ali Hassan Mohammed Mohammed ◽  
Ameer Qassim Majde ◽  
Elaf Sabah Abbas
Keyword(s):  
Differential Equation ◽  
Differential Equations ◽  
Nuclear Physics ◽  
Radioactive Decay ◽  
Engineering Applications

Al-Zughair transform is a novel transformation that is proposed in (2017), and due to its novelty it has not been applied to engineering fields, however Al-Zughair transform is capable to solve differential equations, for that reason it can be applied into engineering applications that include differential equations. In nuclear physics the radioactive decay of the atoms is well study subject, where there are many methods that are used to deal with it, however Al-Zughair transform has never been used before in that field, in this paper the differential equation of radioactive decay has been solved using Al-Zughair transform.  

scholarly journals Measured distribution of cloud chamber tracks from radioactive decay: a new empirical approach to investigating the quantum measurement problem

2021 ◽  
Author(s):  
Jonathan Schonfeld
Keyword(s):  
Spatial Distribution ◽  
Quantum Mechanics ◽  
Quantum Measurement ◽  
Measurement Problem ◽  
Radioactive Decay ◽  
Foundations Of Quantum Mechanics ◽  
Radioactive Source ◽  
Cloud Chamber ◽  
Quantum Measurement Problem ◽  
Measured Distribution

Abstract Using publically available video of a cloud chamber with a very small radioactive source, I measure the spatial distribution of where tracks start, and consider possible implications. This is directly relevant to the quantum measurement problem and its possible resolution, and appears never to have been done before. The raw data are relatively uncontrolled, leading to caveats that should guide future, more tailored experiments. Track distributions from decays in cloud chambers represent a previously unappreciated way to probe the foundations of quantum mechanics, and a novel case of wavefunctions with macroscopic signatures.

The adsorption of dipoles

1940 ◽  
Vol 36 (1) ◽  
pp. 69-78 ◽  
Author(s):  
A. R. Miller
Keyword(s):  
Adsorption Isotherm ◽  
Statistical Method ◽  
Electrostatic Interactions ◽  
Opposite Sign ◽  
Van Der Waals ◽  
Statistical Treatment ◽  
Van Der Waals Forces ◽  
Considerable Effect ◽  
Heat Of Adsorption ◽  
General Shape

In the present paper Bethe's approximation is applied to the statistical treatment of the adsorption of dipoles considering (a) the electrostatic forces alone, and (b) the electrostatic and van der Waals forces jointly. In each case formulae are obtained for the adsorption isotherm and for the variation of the heat of adsorption with the fraction of surface covered. In case (a) the heat curves are compared with those obtained by Wang who used a different approximation to take into account the electrostatic interactions due to particles adsorbed on outer sites. The curves are of the same general shape; sources of differences in them are discussed. In case (b) the results are compared with those obtained by Roberts using a different method. This treatment confirms his result that the electrostatic and van der Waals forces give contributions to the variation of the heat of adsorption which are of opposite sign and almost counterbalance one another, so that the resultant variation in the heat of adsorption is very much less than would be expected from a consideration of forces of one type only. This comparison shows further that the distribution of particles on the surface, which is taken into account in the statistical method used in this paper, has a considerable effect on the variation of the heat of adsorption.

Selenium Metabolism in Patients on Continuous Ambulatory Peritoneal Dialysis

2002 ◽  
Vol 22 (3) ◽  
pp. 400-404 ◽  
Author(s):  
Nicholas S. Apostolidis ◽  
Dimitrios G. Panoussopoulos ◽  
Konstantinos M. Stamou ◽  
Panayotis B. Kekis ◽  
Themis P. Paradellis ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Continuous Ambulatory Peritoneal Dialysis ◽  
Nuclear Physics ◽  
Relevant Literature ◽  
Measurement Data ◽  
Normal Subjects ◽  
Serum Levels ◽  
Total Serum ◽  
Physics Institute ◽  
Se Deficiency

Background Selenium is an essential trace element for living organisms. In many publications, researchers express concern about a possible Se deficiency in patients with end-stage chronic renal failure (ESCRF) undergoing continuous ambulatory peritoneal dialysis (CAPD). However, in a number of published articles, the data provide no evidence that patients under CAPD develop Se deficiency. Objective We investigated Se metabolism in ESCRF patients on CAPD. Setting The study was carried out at the Department of Propaedeutic Surgery, Athens University; the Laboratory for Material Analysis of the Nuclear Physics Institute; and the State General Hospital, Athens, Greece. Patients and Methods The study group included 24 patients on CAPD treatment, 14 ESCRF patients, and 17 healthy controls. We measured the Se and Fe content of serum, blood, and erythrocytes. We also measured hematocrit, serum total proteins and albumins, and Se in dialysate effluent. Results As compared with healthy subjects, the ESCRF and CAPD patients exhibited reduced serum concentrations of Se. However, considering the difference in hematocrit values, the total serum-transported Se per liter of blood was close to normal. Erythrocyte Se proved normal for both groups. The measured Se in the spent effluent indicates that patients under CAPD receive approximately 100 μg Se from their daily diet, as normal subjects do. The Se measurement data from the effluent indicate that 90% of the Se carried by the serum is bound to albumins and that only the remaining 10% is in the form of low molecular weight selenate, free to pass the peritoneal membrane. Of the 24 CAPD patients studied, 4 patients (all women) showed extremely low Se serum levels. Data suggest that those low levels are more likely due to the significantly lower serum albumin levels in the 4 patients than to an insufficient dietary intake. Conclusions Data from the present experimental work suggest that patients undergoing CAPD receive the necessary quantities of Se from their regular diet. The data contradict statements in the relevant literature that CAPD patients develop Se deficiency.

scholarly journals Atmospheric removal times of the aerosol-bound radionuclides <sup>137</sup>Cs and <sup>131</sup>I during the months after the Fukushima Dai-ichi nuclear power plant accident – a constraint for air quality and climate models

2012 ◽  
Vol 12 (5) ◽  
pp. 12331-12356
Author(s):  
N. I. Kristiansen ◽  
A. Stohl ◽  
G. Wotawa
Keyword(s):  
Air Quality ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Dry Deposition ◽  
Nuclear Power ◽  
Climate Models ◽  
Climate Model ◽  
Measurement Data ◽  
Radioactive Decay ◽  
Data Set

Abstract. Caesium-137 (137Cs) and iodine-131 (131I) are radionuclides of particular concern during nuclear accidents, because they are emitted in large amounts and are of significant health impact. 137Cs and 131I attach to the ambient accumulation-mode (AM) aerosols and share their fate as the aerosols are removed from the atmosphere by scavenging within clouds, precipitation and dry deposition. Here, we estimate their removal times from the atmosphere using a unique high-precision global measurement data set collected over several months after the accident at the Fukushima Dai-ichi nuclear power plant in March 2011. The noble gas xenon-133 (133Xe), also released during the accident, served as a passive tracer of air mass transport for determining the removal times of 137Cs and 131I via the decrease in the measured ratios 137Cs/133Xe and 131I/133Xe over time. After correction for radioactive decay, the 137Cs/133Xe ratios reflect the removal of aerosols by wet and dry deposition, whereas the 131I/133Xe ratios are also influenced by aerosol production from gaseous 131I. We find removal times for 137Cs of 10.0–13.9 days and for 131I of 17.1–24.2 days during April and May 2011. We discuss possible caveats (e.g. late emissions, resuspension) that can affect the results, and compare the 137Cs removal times with observation-based and modeled aerosol lifetimes. Our 137Cs removal time of 10.0–13.9 days should be representative of a "background" AM aerosol well mixed in the extratropical Northern Hemisphere troposphere. It is expected that the lifetime of this vertically mixed background aerosol is longer than the lifetime of AM aerosols originating from surface sources. However, the substantial difference to the mean lifetimes of AM aerosols obtained from aerosol models, typically in the range of 3–7 days, warrants further research on the cause of this discrepancy. Too short modeled AM aerosol lifetimes would have serious implications for air quality and climate model predictions.

scholarly journals General Overview of Radon Studies in Health Hazard Perspectives

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Guadie Degu Belete ◽  
Yetsedaw Alemu Anteneh
Keyword(s):  
Ionizing Radiation ◽  
Environmental Protection Agency ◽  
Background Radiation ◽  
Noble Gas ◽  
Indoor Radon ◽  
Health Hazard ◽  
Radioactive Decay ◽  
Indoor Radon Concentration ◽  
Human Respiratory Tract ◽  
Action Levels

The adverse human health effects due to ionizing radiation are well known. Radon is the major source of background radiation among those that are of natural origin. It contributes about 55% of the natural radiation dose to humans. It is a colorless, odorless, and tasteless radioactive noble gas that comes from the natural radioactive decay series of uranium. Radon can be found everywhere in the atmosphere and become attached to aerosols in the air. The aerosols carrying radon and its progeny can be inhaled and deposited in different regions of the human respiratory tract. The deposited radioactive aerosols continue to decay and exposing the lung to ionizing radiation can destroy sensitive cells in the lung, causing a mutation that turns to be cancerous. Different countries and international and national organizations put their action levels to reduce radon lung cancer risk. The Environmental Protection Agency recommends 148 Bq/m3 as the action level. On the other hand, International Commission for Radiation Protection (ICRP) recommends 200 Bq/m3 as the action level. The main objective of this review is to focus on how radon is established as a health hazard, ways of radon detection and measurements, methods of reducing and controlling high indoor radon concentration, and what are the recommended international action levels of radon concentrations. It mainly focuses on the health perspective of radon studies because it is now a crucial and hot issue in the world. In most developing countries like our country Ethiopia, radon studies are not well investigated.

Plutonium and Los Alamos

1995 ◽  
Author(s):  
William L. Graf
Keyword(s):  
Nuclear Physics ◽  
Radioactive Decay ◽  
Central Africa ◽  
Rio Grande ◽  
Physical World ◽  
Beta Radiation ◽  
Entire Family ◽  
Pierre Curie ◽  
Significant Addition ◽  
Northern Rio Grande

The plutonium in the Northern Rio Grande is entirely artificial. Small amounts of plutonium may have formed in exceptionally rich uranium deposits in south-central Africa, but for practical purposes, until its manufacture in 1939, the element did not occur in the earth’s environment. Although the detailed story of the origins of plutonium are beyond the scope of this book, a summary of that history does clarify the issues regarding plutonium in the Northern Rio Grande in the late twentieth century. The purposes of this chapter are to review the origins of plutonium and to examine briefly the nature of that element. Modern nuclear physics, which ultimately led to the production of plutonium, began with the publication of the discovery of X-rays by Wilhelm Conrad Röntgen in 1896. His work showed that the physical world was much more complicated than previously thought and that energy could be emitted from substances. In the same year, Henri Becquerel of Paris showed that uranium emitted radiation, and soon thereafter Marie and Pierre Curie coined the term radioactivity to describe the emissions they recorded from two newly discovered elements, radium (named after its radiative properties) and polonium (named after Marie Curie’s home country of Poland). Between 1898 and 1902, Ernest Rutherford of Cambridge University and, later, McGill University explored processes of radioactive decay that generated free electrons (beta radiation) and bursts of energy (gamma radiation) and discovered that some elements changed their basic properties during the emission. Rutherford termed these changes transmutation and laid the philosophical foundations for understanding atomic structure. The transmutation of elements was a significant addition to the rapidly expanding knowledge about the number and types of elements in the natural world. Between 1894 and 1900, William Ramsey enlarged the periodic table with an entire family of inert gases, and by 1903 more than a dozen radioactive elements were known. By 1903, it was obvious that the decay process explained many observed elemental changes: Americans Bertram B. Boltwood and Herbert N. McCoy showed that radium descended from uranium, and Otto Hahn connected several types of thorium.

Sign in / Sign up

Export Citation Format

Share Document