Radiation-Hygienic Investigations of Experimental Production of Mixed Nitride  Uranium-Plutonium Fuel at JSC SChC. Part 1: Methods and Results

Purpose: To present the methods and results of studies of the factors of radiation exposure to workers involved in the manufacture of mixed uranium-plutonium nitride (MUPN) fuel at the complex experimental installations CEI-1 and CEI-2 of JSC SChC. Material and Methods: Regularities of the formation of external exposure doses have been revealed based on the study of the dynamics of the ambient dose equivalent rate (ADER) of photon and neutron radiation at the CEI-1 and CEI-2 workplaces, as well as instrumental individual dosimetric control of the equivalent doses to workers. In order to assess the inhalation intake and possible doses from internal irradiation, studies of the physicochemical properties of radioactive aerosols were carried out. Results: It has been found that the main sources of penetrating radiation in the premises of CEI-1 are boxes where tablets are pressed, chips and rejected tablets are crushed, as well as temporary storage of products is occurred. The highest ADER values have been measured in those boxes, where the radiation exposure was due to radioactive contamination caused by past activity, and is not associated with fabrication of MUPN fuel. A significant contribution of neutron exposure to individual doses of workers was measured, which exceeded the contribution of gamma exposure at some workplaces of the CEI-1. At CEI-2, a non-functioning exhaust ventilation pipe passing over the premises was found to be a powerful source of external radiation. This pipe contained a significant amount of radioactive material. Assessment of the contribution of gamma exposure from the ventilation pipe to the external exposure of workers reached 85% at some workplaces. Studies of the physicochemical properties of radioactive aerosols have revealed a high reactivity of MUPN compounds, leading to instant oxidation of the thoracic fraction of MUPN fuel aerosols under contact with air. The complex morphological and dispersed composition of aerosol particles in combination with a complex chemical composition caused by the aging processes of aerosols, can lead to a fundamental difference in the biokinetics of MUPN aerosols, the process of dose formation and, consequently, the degree of radiological hazard compared to those adopted in the ICRP models for U and Pu. The results of the current radiation-hygienic research are of a preliminary nature, since the object of this research is an experimental installation, which was used to develop a new technology for the production of MUPN fuel. The instrumental and methodological approaches to assess the factors of radiation exposure to workers tested at these experimental installations, will be used in the future to conduct similar studies during the pilot industrial operation of new modules for fabricating and refurbishing of MUPN fuel.

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Chemical modification and Physicochemical properties of new derivatives 5-(thiophen-3-ilmethyl)-4-R1-1,2,4-triazole-3-thiol

Research Journal of Pharmacy and Technology ◽

10.52711/0974-360x.2021.00803 ◽

2021 ◽

pp. 4621-4629

Author(s):

O.A. Bihdan ◽

V.V. Parchenko

Keyword(s):

Physicochemical Properties ◽

High Reactivity ◽

Biologically Active Compounds ◽

Biologically Active ◽

Active Compounds ◽

Triazole Derivatives ◽

Pharmaceutical Ingredients ◽

Current Trends ◽

Wide Range ◽

Derivatives Of

Current trends in the search for new biologically active compounds among synthetic molecules have arguably proved a priority in studies of the heterocyclic 1,2,4-triazole system. For many years, 1,2,4-triazole derivatives remain the object of close attention of scientists of various scientific fields. The unique properties of 1,2,4-triazole derivatives include high reactivity, which allows different modification of this system, practical absence of toxicity of these derivatives and the presence of a wide range of biological, pharmacological properties, which in the complex provides the prerequisites for the creation of new biologically active compounds, and in the future, active pharmaceutical ingredients (AFI). The aim of our work is to investigate some transformations in a number of derivatives of 5-(thiophen-3-ylmethyl) -4-R1-1,2,4-triazole-3-thiol, to study the physicochemical properties of the new synthesized compounds. A well-known fact remains the successful attempt of many scientists involved in the study of the heterocyclic 1,2,4-triazole system to synthesize potential biologically active compounds. The process of creating new molecules is very painstaking and requires considerable effort. The chemical approaches for the synthesis of the starting compounds required for further transformations are well known and described. Therefore, we used the corresponding N-R1-2 as intermediates for the synthesis of new 5-(thiophen-3-ylmethyl) -4-R1-1,2,4-triazole-3-thiols appropriate ones were used N-R1-2-(2-(thiophen-3-yl) acetyl) hydrazinocarbothioamide.

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General, Divergent Platform for Diastereoselective Synthesis of trans-Cyclooctenes with High Reactivity and Favorable Physiochemical Properties

10.26434/chemrxiv.13669160 ◽

2021 ◽

Author(s):

Jessica E. Pigga ◽

Julia Rosenberger ◽

Andrew Jemas ◽

Samantha Boyd ◽

Olga Dmitrenko ◽

...

Keyword(s):

Physicochemical Properties ◽

Large Scale ◽

High Reactivity ◽

Diels Alder ◽

Synthetic Methods ◽

High Yield ◽

Physiochemical Properties ◽

New Class ◽

State Models

trans-Cyclooctenes (TCOs) are essential partners for the fastest known bioorthogonal reactions, but current synthetic methods are limited by poor diastereoselectivity. Especially hard to access are hydrophilic TCOs with favorable physicochemical properties for live cell or in vivo experiments. Described is a new class of TCOs, ‘a-TCOs’, that is prepared in high yield via stereocontrolled 1,2-additions of nucleophiles to trans-cyclooct-4-enone, which itself was prepared on large scale in two steps from 1,5-cyclooctadiene. Computational transition state models rationalize the diastereoselectivity of 1,2-additions to deliver a-TCO products, which were also shown to be more reactive than standard TCOs and less hydrophobic than even a trans-oxocene analog. Illustrating the favorable physicochemical properties of a-TCOs, a fluorescent TAMRA derivative in live HeLa cells was shown to be cell-permeable through intracellular Diels-Alder chemistry and to washout more rapidly than other TCOs.

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General, Divergent Platform for Diastereoselective Synthesis of trans-Cyclooctenes with High Reactivity and Favorable Physiochemical Properties

10.26434/chemrxiv.13669160.v1 ◽

2021 ◽

Author(s):

Jessica E. Pigga ◽

Julia Rosenberger ◽

Andrew Jemas ◽

Samantha Boyd ◽

Olga Dmitrenko ◽

...

Keyword(s):

Physicochemical Properties ◽

Large Scale ◽

High Reactivity ◽

Diels Alder ◽

Synthetic Methods ◽

High Yield ◽

Physiochemical Properties ◽

New Class ◽

State Models

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ASSESSMENT OF THE RADIATION EXPOSURE FROM THE RADIOACTIVE MATERIAL RELEASED FROM THE STACK OF A 2000 MWe COAL FIRED POWER STATION

Radiation Protection ◽

10.1016/b978-1-4832-8369-2.50036-1 ◽

1980 ◽

pp. 145-148

Author(s):

W.C. Camplin ◽

J. Hallam

Keyword(s):

Radiation Exposure ◽

Radioactive Material ◽

Power Station

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Study on Periodic Shielding Performance Measurements of Spent Fuel Transportation Package

Volume 7: Fuel Cycle, Decontamination and Decommissioning, Radiation Protection, Shielding, and Waste Management; Mitigation Strategies for Beyond Design Basis Events ◽

10.1115/icone25-66036 ◽

2017 ◽

Author(s):

Hongchao Sun ◽

Guoqiang Li ◽

Xuexin Wang ◽

Dajie Zhuang ◽

Renze Wang ◽

...

Keyword(s):

Spent Nuclear Fuel ◽

Measurement Instrument ◽

Neutron Radiation ◽

Radiation Shielding ◽

Radioactive Material ◽

Transportation Safety ◽

Spent Fuel ◽

Performance Measurements ◽

Radiation Level ◽

Neutron Measurement

The radioactive activity of spent nuclear fuel is high, and the transportation safety is concerned by public and specialist. The periodic radiation shielding performance measurements of spent fuels package is important content to ensure transportation safety of spent fuels. The radiation shielding performance of package must meet the requirements of “Regulations for the safe transport of radioactive material” (GB11806-2004). However, some of the problems and difficulties reflected in practice need to be solved, such as the measurements results of neutron radiation level of spent fuels package outer are not always reliable. In this paper, the periodic shielding performance measurements of one type of spent fuel transportation package are presented. The monitoring results of using both the neutron multi-sphere spectrometer and portable neutron measurement instrument are compared, and the Monte Carlo simulation is done to verify the measurements results. Some factors are discussed, and an optimized scheme is recommended.

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Measurement of Neutron Radiation Exposure of Commercial Airline Pilots Using Bubble Detectors

Nuclear Technology ◽

10.13182/nt94-a34967 ◽

1994 ◽

Vol 106 (3) ◽

pp. 373-383 ◽

Cited By ~ 13

Author(s):

Brent J. Lewis ◽

Richard Kosierb ◽

Tom Cousins ◽

Donald F. Hudson ◽

Georges Guéry

Keyword(s):

Radiation Exposure ◽

Neutron Radiation ◽

Airline Pilots ◽

Commercial Airline

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Imaging Advances of the Cardiopulmonary System

Clinical Technologies ◽

10.4018/978-1-60960-561-2.ch812 ◽

2011 ◽

pp. 2183-2190

Author(s):

Holly Llobet ◽

Paul Llobet ◽

Michelle LaBrunda

Keyword(s):

Radiation Dose ◽

Radiation Exposure ◽

High Speed ◽

Imaging Techniques ◽

Radioactive Material ◽

Imaging Modalities ◽

Mri Imaging ◽

Imaging Technology ◽

Magnetic Resonance Imaging Mri ◽

Ct And Mri

A technological explosion has been revolutionizing imaging technology of the heart and lungs over the last decade. These advances have been transforming the health care industry, both preventative and acute care medicine. Ultrasound, nuclear medicine, computed tomography (CT), and magnetic resonance imaging (MRI) are examples of radiological techniques which have allowed for more accurate diagnosis and staging (determination of severity of disease). The most notable advances have occurred in CT and MRI. Most medical subspecialties rely on CT and MRI as the dominant diagnostic tools an exception being cardiology. CT and MRI are able to provide a detailed image of any organ or tissue in the body without the necessity of invasive or painful procedures. Virtually any individual could be tested as long as they are able to remain immobile for the duration of the study. Image generation traditionally has been limited by the perpetual motion of the human body. For example, the human heart is continually contracting and relaxing without a stationary moment during which an image could be obtained. Lung imaging has been more successful than cardiac imaging, but studies were limited to the length of time an ill person is able to hold his or her breath. Historically, imaging technology was limited by inability to take a picture fast enough of a moving object while maintaining a clinically useful level of resolution. Recent technologic innovation, resulting in high speed electrocardiogram- gated CT and MRI imaging, now allows the use of these imaging modalities for evaluation of the heart and lungs. These novel innovations provide clinicians with new tools for diagnosis and treatment of disease, but there are still unresolved issues, most notably radiation exposure. Ultrasound and MRI studies are the safest of the imaging modalities and subjects receive no radiation exposure. Nuclear studies give an approximate radiation dose of 10mSv and as high as 27mSv (Conti, 2005). In CT imaging, radiation dose can vary depending on the organ system being imaged and the type of scanner being used. The average radiation dose for pulmonary studies is 4.2mSv (Conti, 2005). The use of multi-detector CT (MDCT) to evaluate the heart can range from 6.7—13mSv. To put it into perspective, according to the National Institute of Health, an average individual will receive a radiation dose of 360mSv per year from the ambient environment. It is unlikely that the radiation doses received in routine imaging techniques will lead to adverse reactions such as cancer, but patients should be informed of the risks and benefits of each procedure so that they can make informed decisions. It is especially important that patients be informed when radioactive material is to be injected into their bodies. The reasons for this will be discussed later on in the chapter.

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Extraction kinetics, physicochemical properties and immunomodulatory activity of the novel continuous phase transition extraction of polysaccharides from Ganoderma lucidum

Food & Function ◽

10.1039/d1fo02185k ◽

2021 ◽

Author(s):

Guo Liu ◽

Jun Zhang ◽

Tao Hou ◽

Siyu An ◽

Bao yan Guo ◽

...

Keyword(s):

Phase Transition ◽

Physicochemical Properties ◽

Ganoderma Lucidum ◽

New Technology ◽

Continuous Phase ◽

Immunomodulatory Activity ◽

The Novel ◽

Extraction Kinetics ◽

Continuous Phase Transition ◽

Ganoderma Lucidum Polysaccharides

Ganoderma lucidum polysaccharides (GLP) possessed remarkable bioactivity has been studied widely. However, the application of new technology in the polysaccharides extraction has not been investigated. Herein, a novel continuous phase...

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