Transient behavior of a nuclear reactor coupled to an accelerator

Accelerator Driven Systems (ADS) present one of the most viable solutions for transmutation and effective utilization of nuclear fuel. Spent fuel from reactors will be partitioned to separate plutonium and other minor actinides to be transmuted in the ADS. Without the ADS, minor actinides must be stored at a geologic repository for long periods of time. One problem with ADS is understanding the control issues that arise when coupling an accelerator to a reactor. ADSTRANS was developed to predict the transient behavior of a nuclear reactor coupled to an accelerator. It was based on MCNPX, a radiation transport code developed at the LANL, and upon a numerical model of the neutron transport equation. MCNPX was used to generate the neutron source term that occurs when the accelerator is fired. ADSTRANS coupled MCNPX to a separate finite difference code that solved the transient neutron transport equation. A cylindrical axisymmetric reactor with steel shielding was considered for this analysis. Multiple neutron energy groups, neutron precursor groups and neutron poisons were considered. ENDF/B cross-section data obtained through MCNPX was also employed. The reactor was assumed to be isothermal and near zero power level; Unique features of this code are: (1) it predicts the neutron behavior of an ADS for different reactor geometry, material concentration, both electron and proton particle accelerators, and target material, (2) it develops input files for MCNPX to simulate neutron production, runs MCNPX, and retrieves information from the MCNPX output files; Neutron production predicted by MCNPX for a 20 MeV electron accelerator and lead target was compared with experimental data from the Idaho Accelerator Center and found to be in good agreement. The spatial neutron flux distribution and transient neutron flux in the reactor as predicted by the code were compared with analytical solutions and found to be in good agreement. Fuel burnup and poison buildup were also as expected. ADSTRANS is intended to be a valid tool for the simulation of neutron behavior in a nuclear reactor coupled to an accelerator for the transmutation of nuclear waste

Benchmarking photoneutron production of Mcnpx simulations with experimental results

Accelerator driven subcritical systems (ADS) are one of the most viable methods for the transmutation and effective utilization of nuclear fuel. An important aspect of coupling the accelerator to a nuclear reactor is the generation of a high-energy neutron flux. The neutron flux can be generated by hitting a high-Z target composed of lead, tungsten, or other elements with a high-energy proton beam; To explore the control issues arising from coupling a proton accelerator to a subcritical reactor, an electron beam accelerator which produces a similar neutron flux can be used. The purpose of this study is to computationally predict the neutron production rate from a lead target that would couple an accelerator to a subcritical reactor assembly. MCNPX, a radiation transport code developed at the Los Alamos National Laboratory, was used in this study. The MCNPX predictions of photo-neutron production were compared with experimental results performed at Idaho Accelerator Centre (IAC), and showed good agreement

Sustainable Healthcare Tourism in the Post COVID 19 Era

Health tourism in India offers high-quality medical treatments to foreign tourists at affordable prices. The COVID-19 pandemic significantly impacted the industry, leading to a decline in the number of medical tourists. This chapter discusses the government’s response to the crisis and the opportunities for sustainable healthcare tourism in the post-pandemic era. The Indian government issued guidelines for health tourism operators, emphasizing sustainability. These guidelines aim to control the virus’s spread while ensuring the industry’s long-term sustainability. The article explores the potential for sustainable healthcare tourism in India post-COVID and how the industry can attract more foreign tourists by leveraging changing trends. The role of the government in managing the health tourism sector is to highlight and focus on sustainable practices. Measures to ensure the safety of foreign tourists seeking medical treatment in India are discussed, including sustainable infrastructure development, responsible waste management, and resource conservation. By incorporating sustainable practices, the health tourism industry can reduce its environmental impact and contribute to the well-being of local communities

PROTECTIVE EFFECT OF NON-IRRADIATED AND Γ-IRRADIATED MANGO (MANGIFERA INDICA L.) JUICE AGAINST ETHANOL-INDUCED OXIDATIVE STRESS IN ALBINO RATS

ABSTRACTObjective: The aim of this study is to explore the protective effect of non-irradiated and γ-irradiated mango juice (NMJ and GMJ) against ethanolinducedhepatic and renaldysfunctionin rats.Methods: A total of 36 male Wistar rats were selected and randomly divided into six groups of six animals each, and the treatment was given everyday via orogastric tube for 30 days. Group I rats served as normal control group. Group II, III, IV, V, and VI rats received absolute ethanol, NMJ, GMJ,ethanol+NMJ, and ethanol+GMJ, respectively. At the end of experimental period, the animals were sacrificed, and serum was separated for liverand kidney markers analysis. The tissues (liver and kidney) were excised for histopathological changes and lipid peroxidation, enzymatic, and nonenzymaticantioxidantsactivitieswereestimated.Results: Ethanol treatment resulted in the depletion of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-stransferaseactivities,andreducedvitaminCandreducedglutathionecontent,higherlevelofmalondialdehyde,increasedactivitiesofserumalanineaminotransferase,aspartateaminotransferase,alkalinephosphatase,gamma-glutamyltranspeptidase and elevated levels of serum urea, creatinine,uric acid causing malfunction of hepatic, and renal tissues, when compared to control rats. Mango juice (both NMJ and GMJ) co-treatment with ethanolingested rats, were envisaged to possess significant antioxidant defense properties and help in the recovery of tissues from ethanol-induced oxidativedamage. The results showed that degenerative changes in hepatic and renal cells of ethanolic groups were minimized by the administration of mangojuice, as revealed by histopathological examination.Conclusion: The current findings suggest that treatment with mango juice reduces ethanol-induced oxidative stress, thereby protecting the hepaticand renal tissue from ethanol-induced damage.Keywords: γ-irradiation, Mango juice, Ethanol, Oxidative stress, Antioxidant enzymes, Liver, Kidney

Design and development of a reflective membrane for a novel Building Integrated Concentrating Photovoltaic (BICPV) ‘Smart Window’ system

As a new concept, Building Integrated Concentrating PV (BICPV) “smart window” system consisting of a thermotropic layer with integrated PVs is treated as an electricity-generating smart window or glazed façade. This system automatically responds to climatic conditions by varying the balance of solar energy reflected to the PV for electricity generation and transmitted through the system into the building for provision of light and heat. Its success heavily relies on the understanding of the relationship between the transmittance/reflectance properties and the composition of the thermotropic layer under different environmental temperatures. Herein, hydroxypropyl cellulose (HPC) polymer and gellan gum based hydrogel membranes with different compositions were synthesized as the reflective thermotropic layer for the smart BICPV system and their transmittance and reflectance were systematically investigated in terms of hydrogel composition and environmental temperature. Specifically, a switching temperature (Ts) of ~42 °C (6 wt. % HPC) was recorded, the measured transmittance decreases from ~ 90% to ~20%, with the temperature of the reflective layer increasing from 20°C to 60°C. No hysteresis in optical property was observed upon heating-cooling cycle of HPC membrane samples. The measured reflectivity increased with heating from ~10 % below the Ts to ~50 % above the Ts (for 6 wt. % HPC). These features indicate that the as-prepared HPC based thermotropic hydrogel layer holds great potential for application in next generation BICPV smart windows

The effect of passive measures on thermal comfort and energy conservation. A case study of the Hot Summer and Cold Winter climate in the Yangtze River region

The energy consumption for heating and cooling of buildings in the cities located within the boundaries of the Hot Summer and Cold Winter (HSCW) zone in China is rapidly increasing due to the increased comfort expectations from well-resourced occupants. Guidance on how and to what extent it is possible to improve energy efficiency of buildings is thus required by policy makers as well as designers and building managers. The aim of this study is to demonstrate how the use of climate-sensitive passive design solutions can help the improvement of indoor thermal conditions while reducing the energy needs and ultimately carbon emissions. An extensive parametric analysis of several passive strategies such as building orientation, thermal insulation, glazing area, shading devices, air tightness and natural ventilation, is carried out for a typical apartment block located in the cities of Chongqing, Changsha and Shanghai, which lays respectively in the upper, middle and downstream of the Yangtze River. Detailed hourly dynamic simulations show how it is possible to extend the non-heating/cooling period and reduce the peak loads, highlighting the potentialities of each strategy according to different climate constraints. The recommended strategies provides quantitative guidance to either design of new or retrofitting of existing buildings. This research contributes to the building energy conservation knowledge for policy-makers, developers and building designers with insight on the feasibilities of the application of passive measures for the residential buildings located in the Yangtze River region with hot summer and cold winter climates

Achieving environmentally friendly building envelope for Western Australia’s housing sector: a Life Cycle Assessment approach

The rapid growth of Western Australia’s population and economy will affect the sustainability of its building sector. The energy consumption of all processes during mining to material production, transportation, construction plant and tools, and operation (heating, cooling, lighting, hot water and home appliances) stages causes high greenhouse gas (GHG) emissions and embodied energy (EE) consumption. The literature review to date have confirmed that the building envelope consisting of exterior walls, windows, external doors, roof, and floor could significantly affect the energy consumption during operation stage. Australian construction industry could thus enhance the energy efficiency of the building envelope in order to achieve its GHG emissions reduction targets. This paper has assessed the GHG emissions and EE consumption associated with the construction and use of a typical house in Perth for sixty building envelope options using a life cycle assessment (LCA) approach. The results show that the building envelope consisting of cast in situ sandwich wall with polyethylene terephthalate (PET) foam core, double glazed windows, and concrete roof tiles has the lowest life cycle GHG emissions and embodied energy consumption