gamma energy
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2021 ◽  
Author(s):  
NAZIRUL NAZRIN SHAHROL NIDZAM ◽  
Amandeep Sharma ◽  
M.S. Jufa ◽  
M.K. Izzaty ◽  
Imed Boukhris

Abstract A series of borotellurite glass system doped with copper oxide was synthesized using the method of melt quenching. The density of the glass decreases whereas its molar volume increases in respect to copper oxide concentration. The amorphous nature of prepared glasses was proven with the utilisation of XRD spectra. Meanwhile, the glass samples’ elastic properties are determined from the measurement of longitudinal and shear velocities using ultrasonic technique. The longitudinal modulus, shear modulus, bulk modulus and Young’s modulus will show an irregular trend that fluctuates. FLUKA Monte Carlo code is implemented to determine the shielding features at gamma energy 0.3565, 0.6616, 0.8348 and 1.3325 MeV. Linear attenuation coefficients acquired from FLUKA and XCOM are found to be in good agreement with relative difference < 1%. The glass sample B2O3TeO2CuO1 (with highest percentage of TeO2) is found to be the best shielding glass material in this study.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Hugo Freitas ◽  
Paulo Magalhaes Martins ◽  
Thomas Tessonnier ◽  
Benjamin Ackermann ◽  
Stephan Brons ◽  
...  

AbstractThe number of radiotherapy patients treated with protons has increased from less than 60,000 in 2007 to more than 220,000 in 2019. However, the considerable uncertainty in the positioning of the Bragg peak deeper in the patient raised new challenges in the proton therapy of prostate cancer (PCPT). Here, we describe and share a dataset where 43 single-spot anterior beams with defined proton energies were delivered to a prostate phantom with an inserted endorectal balloon (ERB) filled either with water only or with a silicon-water mixture. The nuclear reactions between the protons and the silicon yield a distinct prompt gamma energy line of 1.78 MeV. Such energy peak could be identified by means of prompt gamma spectroscopy (PGS) for the protons hitting the ERB with a three-sigma threshold. The application of a background-suppression technique showed an increased rejection capability for protons hitting the prostate and the ERB with water only. We describe each dataset, document the full processing chain, and provide the scripts for the statistical analysis.


2021 ◽  
Vol 27 (4) ◽  
pp. 405-409
Author(s):  
Min Lin

ABSTRACT Objective: The paper uses artificial neural network images to explore the effects of aerobic exercise on the gamma rhythm of theta period in the awake hippocampal CA1 area of APP/PS1/tau mice and the low-frequency gamma rhythm of the sleep state hippocampal CA1 area SWR period. Methods: Clean grade 6-month-old APP/PS1/tau mice were randomly divided into quiet group (AS) and exercise group (AE), C57BL/6J control group mice were randomly divided into quiet group (CS) and exercise group (CE). The AE group and the CE group performed 12-week treadmill exercise, 5d/week, 60min/d, the first 10min exercise load was 12m/min, the last 50min was 15m/min treadmill slope was 0°. Eight-arm maze detection of behavioral changes in mice; multi-channel in vivo recording technology to record the electrical signals of the awake state and sleep state in the hippocampal CA1 area, MATLAB extracts the awake state theta period and sleep state SWR period, multi-window spectrum estimation method Perform time-frequency analysis and power spectral density analysis. Results: 12 weeks of aerobic exercise can significantly improve the working memory and reference memory of the AS group, increase the gamma energy in theta period of the awake hippocampus CA1 area and the low-frequency gamma energy in the sleep state CA1 area SWR period. Conclusions: Aerobic exercise can improve the neural network state of the AD model and increase the gamma energy in theta period of the hippocampus CA1 area, and the low-frequency gamma energy in the SWR period is one of the neural network mechanisms for its overall behavioral improvement. Level of evidence II; Therapeutic studies - investigation of treatment results.


2021 ◽  
Vol 73 (07) ◽  
pp. 69-70
Author(s):  
Chris Carpenter

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 202210, “Future Roles for Natural Gas in Decarbonizing the Australian Electricity Supply Within the NEM: Total System Costs Are Key,” by Stephanie Byrom, University of Queensland; Geoffrey Bongers, Gamma Energy Technology; and Andy Boston, Red Vector, et al., prepared for the 2020 SPE Asia Pacific Oil and Gas Conference and Exhibition, originally scheduled to be held in Perth, Australia, 20–22 October. The paper has not been peer reviewed. Electricity systems around the world are changing, with the Paris Agreement of 2015 a catalyst for much current change. The Australian government ratified the agreement by committing to 26–28% emissions reductions below 2005 levels by 2030. Reduction in emissions from electricity generation has become the focus of these targets. To decarbonize the grid to meet targets while building firm, dispatchable generation capacity to support the system, a new metric is required to measure success. The complete paper explores the outputs of the model of energy and grid services (MEGS), illustrating outcomes if a single technology group is favored. Introduction The majority of electricity in the Australian National Energy Market (NEM) is provided by synchronous thermal power generation, which also has delivered services required for grid stability such as inertia and frequency control. The NEM commenced operation in December 1998 and includes five regional market jurisdictions: Queensland, New South Wales (including the Australian Capital Territory), Victoria, South Australia, and Tasmania. In 2020, the NEM incorporated approximately 40,000 km of transmission lines and cables, connecting approximately 57 GW of generation capacity to consumers. This thermal generation mostly has consisted of coal- and gas-based technologies. Electricity grids are also changing from largely centralized electricity generation systems to more decentralized ones and from unidirectional electricity flows to bidirectional flows as part of the effort to reduce emissions. However, with increasing penetration of variable renewable energy (VRE) generation, it is important to plan for and manage generation-asset investment to track the lowest possible total system cost and highest reliability path to a low-emissions future. A Competent, Diverse Grid A competent electricity grid is one that can keep the lights on, so to speak, within the legislated tolerance for outages and performance. A competent grid is adequate, reliable, secure, operable, and robust against externally driven disruptions. In practice, the reliability of the electricity grid often seems to be taken for granted; however, it is an essential element of the modern economy, and, with a changing grid, reliability is increasingly important. When a decision must be made to build or replace an individual power plant, stakeholders (individual investors) have traditionally considered the levelized cost of energy (LCOE) of the alternative generation options, which di-vides the total cost of an installation or plant by the kilowatt-hours it produces over its lifetime. However, metrics such as LCOE, based on grid-independent formulae to help power plant investors to maximize returns, are inappropriate for comparing technologies that deliver and demand a complex menu of services specific to the grid. A different metric is required to evaluate each technology’s contribution to the grid.


Author(s):  
Faruk Jayanto Kelutur ◽  
Holis Abdul Holik

A B S T R A C TTechnetium-99m ( 99m Tc) has been applied in nuclear medicine as a radiopharmacyfor both diagnosis and therapy. 99m Tc is obtained from a 99 Mo/ 99m Tc (half-life 66 h)generator in the form of sodium pertechnetate (Na[ 99m TcO 4 ]) by decaying to 99 Tc for 6hours and emitting gamma energy rays (Eɤ = 140 keV). This radionuclide has anelectron configuration of 4d 5 5s 2 , which will form complexes with different ligandsand have oxidation rates from +1 to +7. The coordinated complex of technetium-99mhas been utilized in nuclear medicine in tissues and organs (thyroid, red and whiteblood cells, kidneys, brain, myocardial, and bone). The resulting kit production musthave based on Good Manufacturing Practice, which consists of batch planning,washing, sterilization of glassware and stopper, starting material, preparation oflarge quantities of the solution, sterile filtration, dispensing, crimping, a summary ofprocess control, quarantine, packaging and leaving the production premises.


2021 ◽  
Vol 61 (2) ◽  
pp. 375
Author(s):  
Stephanie Byrom ◽  
Geoffrey D. Bongers ◽  
Andy Boston

As the National Energy Market (NEM) changes to a more diverse grid with emissions reduction targets, the way we value technologies must also change (Boston et al. 2017). This change in value is fundamental as the future low emissions grid will require careful planning and implementation to guarantee the lowest total system cost is maintained, particularly as a net zero grid will be drastically larger than the current system. This planning must include system strength. The Australian Energy Market Operator Integrated System Plan states that the current market mechanisms cannot facilitate achieving a low emissions grid (Australian Energy Market Operator (AEMO) 2020a). Policy and market mechanisms will need to be designed for this changing system. If net zero is to be met, Modelling of Energy and Grid Services by Red Vector and Gamma Energy technology has shown that this future grid needs to contain: approximately 100GW of variable renewable energy; almost 20GW of firm, low emissions generation, such as gas or coal with carbon capture and storage (CCS), bioenergy with CCS and hydroelectric power. If CCS is not available, nuclear power will be required; more than 10GW of storage, including pumped hydro energy storage and other energy storage technologies and over 30GW of firm, dispatchable peaking plant, including coal- and gas-fired power generation. This study sets out the role for gas in a policy road map to net zero for the NEM, harnessing and reforming existing policies, as well as introducing new mechanisms to achieve net zero emissions while retaining a reliable grid at the lowest total system cost.


Author(s):  
Tran Thien Thanh ◽  
Van Tan Phat ◽  
Le Hoang Minh ◽  
Huynh Dinh Chuong ◽  
Vo Hoang Nguyen ◽  
...  

The characteristic parameters of a material relation to photon interactions such as: mass attenuation coefficient, effective atomic number, effective electron density are required to provide essential data in diverse works such as nuclear diagnostic and cancer radiotherapy, industrial irradiation, radiation dosimetry, radiation protection and shielding, analyzing of the concentration of elements and radioactive isotopes. In this paper, the theoretical models such as non-relativistic form factor (NRFF), relativistic form factor  (RFF), and modified form factor (MFF) were used to calculate the ratio Rayleigh-Compton for elements with at gamma energy 59.5 keV. The results showed that there was a discrepancy between the theoretical modes at a high atomic number. The mean value of the Rayleigh-Compton ratio depends on the atomic number, which shows the quadratic function of the correlation coefficient R2 = 0.996 as well. Besides, the experimental system was set-up and measured for some targets such as aluminum, copper, and lead at a scattering angle 150o using 241Am source by Si(Li) detector to confirm the theoretical values. The preliminary result showed that there was a good agreement with experimental and theoretical results is lower than 20%. Further investigation will be measured by the samples for more detailed evaluation.


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