Radioactive Substances Research Articles

Impact of Natural Hazards on the Operation of Powered Roof Support in Polish Hard Coal Mines

The powered roof support is mainly used in natural hazard conditions. Natural hazards in Polish mining include methane hazards, gas and rock ejections, coal dust explosions, climate hazards, water hazards, landslides, eruptions, hydrogen sulphide hazards, radioactive substances hazards and rock mass tremors. The latter has a significant impact on the operation of powered roof support. The work analyses rock mass tremor risks in the last ten years. The study showed an intense increase in this hazard, which significantly affects the work safety of people operating machines and devices in mining excavations. The paper takes into consideration surveys carried out among employees working in conditions of rock mass shock risk. The purpose of the study was to obtain information on the safe operation of powered roof supports. The data allowed us to draw conclusions regarding the possibility of increasing work safety regarding rock mass shock risk conditions.

Air Kerma Calculation in Diagnostic Medical Imaging Devices Using Group Method of Data Handling Network

The air kerma, which is the amount of energy given off by a radioactive substance, is essential for medical specialists who use radiation to diagnose cancer problems. The amount of energy that a photon has when it hits something can be described as the air kerma (the amount of energy that was deposited in the air when the photon passed through it). Radiation beam intensity is represented by this value. Hospital X-ray equipment has to account for the heel effect, which means that the borders of the picture obtain a lesser radiation dosage than the center, and that air kerma is not symmetrical. The voltage of the X-ray machine can also affect the uniformity of the radiation. This work presents a model-based approach to predict air kerma at various locations inside the radiation field of medical imaging instruments, making use of just a small number of measurements. Group Method of Data Handling (GMDH) neural networks are suggested for this purpose. Firstly, a medical X-ray tube was modeled using Monte Carlo N Particle (MCNP) code simulation algorithm. X-ray tubes and detectors make up medical X-ray CT imaging systems. An X-ray tube's electron filament, thin wire, and metal target produce a picture of the electrons' target. A small rectangular electron source modeled electron filaments. An electron source target was a thin, 19,290 kg/m3 tungsten cube in a tubular hoover chamber. The electron source-object axis of the simulation object is 20° from the vertical. For most medical X-ray imaging applications, the kerma of the air was calculated at a variety of discrete locations within the conical X-ray beam, providing an accurate data set for network training. Various locations were taken into account in the aforementioned voltages inside the radiation field as the input of the GMDH network. For diagnostic radiology applications, the trained GMDH model could determine the air kerma at any location in the X-ray field of view and for a wide range of X-ray tube voltages with a Mean Relative Error (MRE) of less than 0.25%. This study yielded the following results: (1) The heel effect is included when calculating air kerma. (2) Computing the air kerma using an artificial neural network trained with minimal data. (3) An artificial neural network quickly and reliably calculated air kerma. (4) Figuring out the air kerma for the operating voltage of medical tubes. The high accuracy of the trained neural network in determining air kerma guarantees the usability of the presented method in operational conditions.

Radioguided surgery of mesenchymal tumors with 125I seeds

IntroductionRadioguided surgery uses radioactive substances to identify and remove hard-to-locate lesions. Mesenchymal tumors constitute a heterogeneous group of neoplasms derived from the mesoderm, including benign lesions and malignant sarcomas. The aim of this study was to evaluate the ability of 125I radioactive seeds to guide intraoperative localization of mesenchymal tumors, analyzing the complication rates and evaluating the margins of the surgical specimens retrieved. MethodsRetrospective observational study of all consecutive patients undergoing radioguided surgery of a mesenchymal tumor with a 125I radioactive seed from January 2012 to January 2020 at a tertiary referral center in Spain. The seed was inserted percutaneously guided by ultrasound or computed tomography in an outpatient setting. ResultsFifteen lesions were resected in 11 interventions in 11 patients, recovering all lesions marked (100%) with a 125I seed. The lesions included areas of benign fibrosis (26.7%), cellular angiofibroma (6.7%), desmoid tumor (20%), solitary fibrous tumor (13.3%), chondrosarcoma (6.7%), and pleomorphic sarcoma (26.7%), with a high rate of recurrent tumors (60%). There was only one complication (6.7%) due to the seed falling within the surgical bed. According to the UICC classification of residual tumors, 80% of the lesions resulted in an R0 resection, 6.7% were R1 resections, and 13.3% were R2 resections. ConclusionRadioguided surgery is an accurate technique for the resection of hard-to-locate mesenchymal tumors.

FORECASTING OF RADIOACTIVE CONTAMINATION OF ATMOSPHERIC AIR IN AN EXTREME SITUATION AT NPP

Problem statement. The task of assessing the level of atmospheric air radioactive contamination in the case of an extreme situation on the territory of the Zaporizhzhya NPP, which leads to an instantaneous radioactive aerosol emission, is considered. An analysis of the dynamics for the zones’ formation of radioactive contamination in the wind direction towards Nikopol is conducted. For the prompt solution of this of this forecast issue, the creation of a multifactorial numerical model is required, which allows for prompt analysis of the size and intensity of radioactive contamination areas. The purpose of the article. Creation of a numerical model and computer code for the operational analysis of radioactive contamination areas formed during the instantaneous release of radioactive pollutants into the atmosphere. Methodology. The computer code is based on a numerical model, which is a differential analogue of the multifactor kinematic equation of mass transfer of a radioactive impurity in atmospheric air. The mass transfer equation takes into account the wind speed field, atmospheric turbulent diffusion, and the intensity of radioactive substances emission into the air. For the numerical integration of the mass transfer equation, the splitting method is used followed by the use of finite-difference schemes. Determination of the volumetric activity value at each splitting step is implemented by an explicit formula. Scientific novelty. An effective numerical model was developed and its software implementation was conducted for operational analysis of the formation of radioactive contamination areas in the atmosphere during an extreme situation at a nuclear power plant, accompanied by the emission of radioactive substances. The model takes into account a complex of factors that affect the process of radioactive impurities spread in the atmosphere. Practical value. A computer code was developed for calculating the dynamics of the formation of radioactive contamination zones in the atmosphere based on the developed numerical model. This makes it possible to analyze the consequences of emergency emissions on the territory of the NPP using the computational experiment method. Conclusions. A mathematical model was developed for the operational analysis of radioactive contamination level of the atmospheric air due to an extreme situation at the nuclear power plant, which leads to an intense instantaneous release of radioactive substances. The results of a computational experiment based on the developed numerical model are presented.

Inflammatory Networks in Renal Cell Carcinoma.

Cancer-associated inflammation has been established as a hallmark feature of almost all solid cancers. Tumor-extrinsic and intrinsic signaling pathways regulate the process of cancer-associated inflammation. Tumor-extrinsic inflammation is triggered by many factors, including infection, obesity, autoimmune disorders, and exposure to toxic and radioactive substances. Intrinsic inflammation can be induced by genomic mutation, genome instability and epigenetic remodeling in cancer cells that promote immunosuppressive traits, inducing the recruitment and activation of inflammatory immune cells. In RCC, many cancer cell-intrinsic alterations are assembled, upregulating inflammatory pathways, which enhance chemokine release and neoantigen expression. Furthermore, immune cells activate the endothelium and induce metabolic shifts, thereby amplifying both the paracrine and autocrine inflammatory loops to promote RCC tumor growth and progression. Together with tumor-extrinsic inflammatory factors, tumor-intrinsic signaling pathways trigger a Janus-faced tumor microenvironment, thereby simultaneously promoting or inhibiting tumor growth. For therapeutic success, it is important to understand the pathomechanisms of cancer-associated inflammation, which promote cancer progression. In this review, we describe the molecular mechanisms of cancer-associated inflammation that influence cancer and immune cell functions, thereby increasing tumor malignancy and anti-cancer resistance. We also discuss the potential of anti-inflammatory treatments, which may provide clinical benefits in RCCs and possible avenues for therapy and future research.

EVAPORATION OF METHYLATED SPIRIT AS AN ALTERNATIVE METHOD OF RADIOACTIVITY DEMONSTRATION IN PHYSICS AND CHEMISTRY AT SECONDARY SCHOOL LEVELS

Practical demonstrations by teacher and learner, especially in Science Education, make teaching-learning process pragmatic, learner-centred, easier to understand, and more appreciated. Also, it has been observed that radioactivity is one of the important topics in Physics and Chemistry at Secondary School levels. Unfortunately, its concept appears abstract and illusion in the minds of the learners due to lack of practical demonstrations or experimentation of the theory. The reason for such deficiency may be attributed to hazardous nature of radioactive substances, strict legal regulations on their exposures (both at the international and domestic levels), associated risk during transportation and handling, etc. The essence of this research is to devise a way of practically demonstrating radioactivity by utilising a non-radioactive substance that is cheaply available with high level of sustainability and potential to exhibit decay. Specifically, methylated spirit was used as the non-radioactive substance in this study. It was put in a syringe clamped vertically with an open end facing up and timing of its evaporation was performed separately for intervals of 10 minutes and 15 minutes. In each case, the volume of the methylated spirit left was recorded and the data obtained were analysed It was observed that the volume – time relationships were of exponential decay characteristic supported by empirical formula governing radioactivity, notwithstanding the time intervals considered. For 10 minutes interval consideration, the results showed evaporation constant (which is analogous to decay constant), and half-life to be 8.14 x 10-4 min-1, and 851.4 minutes respectively whereas in the case of 15 minutes interval, they were found to be 8.40 x 10-4 min-1, and 825.0 minutes respectively. Hence, it could be adjudged that methylated spirit is a promising non-radioactive substance for practical experiment/demonstration to make teaching and learning of radioactivity learner-centred for a better understanding of the topic in Physics and Chemistry at Secondary School levels.

Thermal-hydraulic optimization of a proposed EU-DEMO hydrogen passive removal system

As the R&D of magnetic fusion power demonstrating plants are approaching important steps toward concept designs, analysts are working parallelly on the safety assessment of such concepts to identify any potential risk. One of the safety concerns involves the confinement of radioactive substances during normal operation and accidental conditions. Several accident sequences inside the tokamak vacuum vessel or pressure suppression systems are characterized by the risk of hydrogen buildup and subsequent ignition that could threaten the structural confinement integrity. In the Safety and Environment work package of the EUROfusion consortium, possible approaches to mitigate the hydrogen explosion risk are under investigation. One of the exploratory solutions is based on limiting the hydrogen concentration that could reach flammable gas mixture conditions and using Passive Autocatalytic Recombiners (PARs) installed into the atmosphere of the pressure suppression systems tanks to recombine hydrogen.This paper examines the theoretical effectiveness of the PARs intervention during an in-vessel loss of coolant accident without the intervention of the decay heat removal system for the Water-Cooled Lithium Lead (WCLL) concept of EU-DEMO, using an optimization methodology. The involved systems have been modelled in MELCOR to estimate the PARs recombination capability as a function of the thermal-hydraulic parameters of the suppression tanks. Furthermore, the optimizer entity of the RAVEN tool is applied to perform optimization studies on the hydrogen recombination system design parameters. The goal is to explore the geometrical and thermal-hydraulic parameters that maximize the capability of the hydrogen removal system for the WCLL concept.

Proposal of a quantitative approach integrating radioactive and chemical risks

A number of situations lead to risks associated with both radionuclides and chemicals exposures: management of contaminated sites, NORM industries, management of indoor air quality, occupational risks, etc. Risk assessment and risk management associated with chemical and radioactive substances are based on different approaches and risk metrics, making it possibly hard to compare those risks and to manage risks in a commensurate way. This article presents a method to express health risk using a common metric, the DALY (Disability-Adjusted Life Year), which is used among others by WHO to guide public health policies. The proposed approach, allowing for comparison, hierarchy and aggregation of risks associated with exposure to ionizing radiations and chemical substances, can support communication and dialog between stakeholders on complex situations.

STUDIES OF FISH AND FISH PRODUCTS FOR THE PRESENCE OF HEAVY METAL SALT AND RADIONUCLIDES IN WATER BODIES OF THE WEST KAZAKHSTAN REGION

With the increase in production and processing industries, as well as the extraction of minerals in the territory of the Republic of Kazakhstan, it leads to pollution of the environment, ecology, wildlife and water resources of our country. All production capacities in agriculture and animal husbandry require water resources. As part of the research work, diagnostics were carried out on the content of salts of heavy metals and radioactive substances in the water bodies of the West Kazakhstan region, where they originate with transboundary rivers and an oil and gas field (KPO) is being produced. To carry out our research work, samples of fish products were taken from 15 reservoirs and 3 objects of domestic trade for laboratory testing for the content of salts of heavy metals (Pb, Cd) and radionuclides (Sr-90, Cs 134). Radioactive substances accumulate in the bones and muscles of fish, and subsequently enter the human body through ingestion. The risk of developing adverse effects on human health depends on the radiation dose. If the radiation dose is low, or if exposure occurs over a long period of time, the risk is much lower as the human body repairs damaged cells and molecules. Lead and cadmium harm the human nervous system and its mental development, it can cause kidney damage and lead to bone disease. It is necessary to constantly monitor the content of salts of heavy metals and radionuclides in fish and livestock products, since safe products are a guarantee of public health.

Research for forecasting the effect of various meteorological-dynamic conditions on the possible spreading of Cs-137 radioactive substances in case a level 7 incident occurs from Fengcheng nuclear power plant (China)

Because its location is quite close to the Vietnamese border, the future operation of the Fengcheng (Phong Thanh) nuclear power plant (NPP) can raise many concerns about the impact on the marine environment in case a serious incident occurs. Based on the Delft3D modeling toolkit, calculation scenarios to simulate the spreading of Cs-137 radioactive emission when a level 7 incident occurs at Phong Thanh NPP have been set up according to different dynamic/meteorological conditions presented at the time of incidents (during the northeast monsoon, transitional monsoon, or southwest monsoon) to assess/predict the possibility of radioactive emission and to spread, and their affecting the waters of Vietnam. The simulation results show that when a level 7 incident occurs from Phong Thanh NPP, the area of influence might be the entire East Sea after 3–6 months. The Gulf of Tonkin area would be contaminated with high radiation levels (300–350 Bq/m3) after about one month. The radiation would then gradually decrease to less than 150Bq/m3 after one year and below 30Bq/m3 after two years. The impacts of various dynamical and meteorological conditions on the ability to spread and disperse radioactive substances when an incident occurs are only evident in the early stages (up to 3 months after the incident). After this time, the contaminated area would cover almost the entire coastal strip of Vietnam due to a large amount of radiation, and the effects of different dynamic/meteorological conditions would be irregular.

RADON EXPOSURE AND LUNG CANCER

Radon causes lung cancer and the death rate is reaching high numbers every year, making it the second most important cause of lung cancer after tobacco use. The World Health Organization (WHO) has classified radon as a carcinogenic substance that causes lung cancer. Radon is a naturally occurring, radioactive substance found mostly in soil or rock. The products obtained as a result of radioactive decay of radon are entering into the body through the respiratory tract. After, these radioactive elements are emitting α-particles that affect the lung tissue, resulting the lung cancer after long-term exposure. Epidemiological studies first revealed a high correlation between the incidence of lung cancer and exposure to radon-related elements among miners in Europe. After that, they began collecting the data and investigations about radon exposure in homes and lung cancer incidence. Many international studies have shown an increase in the risk ratio of lung cancer when indoor radon concentrations are high.

Passive Hydrogen Recombination during a Beyond Design Basis Accident in a Fusion DEMO Plant

One of the most important environmental and safety concerns in nuclear fusion plants is the confinement of radioactive substances into the reactor buildings during both normal operations and accidental conditions. For this reason, hydrogen build-up and subsequent ignition must be avoided, since the pressure and energy generated may threaten the integrity of the confinement structures, causing the dispersion of radioactive and toxic products toward the public environment. Potentially dangerous sources of hydrogen are related to the exothermal oxidation reactions between steam and plasma-facing components or hot dust, which could occur during accidents such as the in-vessel loss of coolant or a wet bypass. The research of technical solutions to avoid the risk of a hydrogen explosion in large fusion power plants is still in progress. In the safety and environment work package of the EUROfusion consortium, activities are ongoing to study solutions to mitigate the hydrogen explosion risk. The main objective is to preclude the occurrence of flammable gas mixtures. One identified solution could deal with the installation of passive autocatalytic recombiners into the atmosphere of the vacuum vessel pressure suppression system tanks. A model to control the PARs recombination capacity as a function of thermal-hydraulic parameters of suppression tanks has been modeled in MELCOR. This paper aims to test the theoretical effectiveness of the PAR intervention during an in-vessel loss of coolant accident without the intervention of the decay heat removal system for the Water-Cooled LithiumLead concept of EU-DEMO.

Assessment of the soil - geobotanical condition of forest fund land plots on the example of the Orlinogorsk forestry

The land fund is in constant motion. Lands are transferred from some categories and lands to others. The deterioration of the ecological state of the lands, the development of erosion processes, desertification, salinization, pollution with chemical and radioactive substances, overgrowth of forest and shrub lands annually exclude significant areas from use. During the reconnaissance route-loop survey of land plots, types of plant associations were identified. Mainly, the identification of types of plant associations made it possible to conduct a preliminary assessment on the ground about the quality of the studied sites for the restoration of forests. Work has been carried out on the study of forest areas located on the territory of Northern Kazakhstan. The surveyed sites are located in the forest-steppe zone on the right-bank side of the Ishim River in the North Kokchetav subdistrict. The study of the soil was carried out by the method of laying soil sections and semi-sections with a description of the power of horizons. The soil structure was determined by the method of splitting soil samples. Based on the results of the study, recommendations were developed for the categories of areas. The areas of plots suitable for all major forest species and areas with existing forests, forest crops overgrown with self-seeding were also determined. General recommendations were formed during the direct conduct of surveys on the ground, but systematic monitoring, using remote sensing methods of the Earth, could facilitate the ongoing research. The development of the method of integrated ecological and geographical research in the future can significantly increase the efficiency of forest management work in general and minimize losses associated with environmental influences.

Deprivation of Furusato: The damage faced by evacuees after the Fukushima nuclear power plant accident

AbstractThis paper considers the damage caused by the Great East Japan Earthquake and the meaning of the Fukushima Nuclear Power Plant accident, and reflects on the evacuees' experiences over past 12 years. During this time, several lawsuits demanding the clarification of responsibility for the accident and compensation for damages have been filed against TEPCO (Tokyo Electric Power Company) and the Japanese Government. The “loss and transformation of hometowns (furusato in Japanese)” has become one of the key issues in these lawsuits. While the casees were being litigated, the mandated “evacuation designated zones” were gradually lifted. Even in the “Difficult‐to‐Return Areas” where annual integrated doses of radioactive substances are over 50 mSv and evacuation orders are still in effect, efforts are being made to lift the evacuation orders. Because they were forced to leave their places of residence, evacuees have claimed, “we lost oue furusato [hometown].” However, because they are able to return after evacuation orders are lifted, both TEPCO and the Japanese Government have insisted that “their furusato has not been lost” and “they cannot claim compensation for furusato damages.” In this paper, I call the irreversible and absolute damage caused by the nuclear power plant accident “the deprivation of furusato.” I look at furusato from three aspects: the relationship between people and nature, the connection between people, and notions of persistence and sustainability. Then, I discuss what kind of reconstruction is being promoted to respond to the deprivation of furusato and for whom.

Разработка методов получения углеродных адсорбентов на основе Ангренского угля и нефтяных остатков

Currently, activated carbon adsorbents are widely used in the world for industrial wastewater treatment from various organic compounds, sorption of heavy metal ions and life-threatening radioactive substances. Carbon adsorbents with hydrophobic properties are mainly modified based on the brown coal, coke, scape, and bark of plants. The methods of manufacturing coal adsorbents based on Angren coal, petroleum coke and asphaltenes are listed. The physicochemical composition and complete thermodynamic properties of the activated carbon adsorbent were studied. It was found that during the heat treatment of mixtures of carbonaceous raw materials, its mass is lost with increasing temperature. At the same time, the adsorption activity of iodine increases with increasing temperature. Depending on the change in temperature of the obtained carbon adsorbent samples, the calculated surface area with respect to iodine is 280.7 m2/g with a weight loss of 0.2 g. The differential heat of adsorption, isotherm, molar entropy and thermokinetics of the benzene and toluene molecules studied in the article are calculated. The adsorption of 4.5 mmol/g of benzene and 3.5 mmol/g of toluene on the activated carbon adsorbent was determined. It is noted that during the adsorption of benzene and toluene by the obtained adsorbent from activated carbon, the differential heat of reaction gradually decreases. When recalculating the isothermal adsorption of benzene and toluene on activated carbon according to the equation of the volumetric theory of micropore saturation, it was obtained that 84.5 % of benzene and 94.2 % of toluene were adsorbed on the pores of the adsorbent.

Numerical Simulation of Airflow and Dust Migration in Vacuum Vessel During Loss of Vacuum Accident for Updated CFETR

A loss of vacuum accident (LOVA) occurs during in-vessel component failure and air ingress. The airflow characteristics of a LOVA are determined by many factors like initial pressure, location of a break, and size of a break and have a great impact on dust migration, which could cause a serious explosion with incoming air and H2. In this paper, a computational fluid dynamics method is adopted, and the k-ε Shear Stress Transport model for airflow and the Discrete Phase Model for dust are used to simulate a LOVA with the updated Chinese Fusion Engineering Test Reactor (CFETR) tokamak device. The effects of initial pressure, break size, and break location on airflow during the LOVA are discussed, and the effects of dust size, break size, and break location on dust migration during the LOVA are investigated as well. The results indicate that the initial pressure and size of a break have a greater impact on airflow of a LOVA than the location of the break and that both the dust size and the characteristics of the airflow have a greater impact on the distribution of the dust. A break located in the upper port has even more dust chaos. This research is the basis for the safety analysis of the CFETR device, and it provides a reference for subsequent studies on dust removal, mitigation of dust explosions, and radioactive substances.

Optimized production of 67Cu based on cross section measurements of 67Cu and 64Cu using an 18 MeV medical cyclotron

RadioNuclide Therapy (RNT) in nuclear medicine is a cancer treatment based on the administration of radioactive substances that specifically target cancer cells in the patient. These radiopharmaceuticals consist of tumor-targeting vectors labeled with β−, α, or Auger electron-emitting radionuclides. In this framework, 67Cu is receiving increasing interest as it provides β−-particles accompanied by low-energy γ radiation. The latter allows to perform Single Photon Emission Tomography (SPECT) imaging for detecting the radiotracer distribution for an optimized treatment plan and follow-up. Furthermore, 67Cu could be used as therapeutic partner of the β+-emitters 61Cu and 64Cu, both currently under study for Positron Emission Tomography (PET) imaging, paving the way to the concept of theranostics. The major barrier to a wider use of 67Cu-based radiopharmaceutical is its lack of availability in quantities and qualities suitable for clinical applications. A possible but challenging solution is the proton irradiation of enriched 70Zn targets, using medical cyclotrons equipped with a solid target station. This route was investigated at the Bern medical cyclotron, where an 18 MeV cyclotron is in operation together with a solid target station and a 6-m-long beam transfer line. The cross section of the involved nuclear reactions were accurately measured to optimize the production yield and the radionuclidic purity. Several production tests were performed to confirm the obtained results.

Ensemble of Below-Cloud Scavenging Models for Assessing the Uncertainty Characteristics in Wet Raindrop Deposition Modeling

This work is devoted to the development of an ensemble of below-cloud scavenging models of pollutant aerosol transport into the atmosphere. Among other factors contributing to the uncertainty of the forecasts of the dispersion and deposition of technogenic gas-aerosol releases in the atmosphere, precipitation scavenging is one of the least studied and, in case of precipitation, can be the dominant mechanism for aerosol deposition. To form the ensemble of below-cloud scavenging models, appropriate experimental data, raindrop-aerosol capture models, raindrop terminal velocity parameterizations, and raindrop size distributions were chosen. The pool of models was prepared and then evaluated to adequately describe the experimental data using statistical analysis. Rank diagrams were used to analyze the adequacy of meteorological ensembles; together with the ensemble distribution construction, they allowed selecting the groups of models with such properties as to produce unbiased estimates and dispersion corresponding to the dispersion of the experimental data. The model calculations of the concentration fraction deposited due to below-cloud scavenging were performed using a log-normal distribution with characteristics corresponding to those observed during the accidents at the Chernobyl NPP and Fukushima-1 NPP. The results were compared with those obtained using the models of the NAME and FLEXPART codes. The results of this work can be used to improve the current approaches applied for modelling the distribution of pollutants in the atmosphere in the case of emergency, enhancing the reliability of forecasts by taking into account uncertainties in the results. The formed multi-model ensemble will be included in the decision support system used in responding to releases of radioactive substances into the atmosphere.

Phytotoxicity Assessment and Nanotechnological Remediation of Textile Industrial Dyes on Vegetation

In current scenario, one of the most significant sources of pollution is textile dye and increasing day by day. Many issues confront global agriculture, including the sustainable use and protection of natural resources, climate change, urbanisation, and pollution caused by agrochemicals (e.g., fertilisers and pesticides). These businesses release a wide range of chemicals, dyes, acids and alkalis, as well as other toxic compounds such as heavy metals, all of which are known to be poisonous. The physico-chemical parameters of dye manufacturing effluents, as well as their impact on seed germination and plant growth, were studied. Nanotechnology is also being studied as a potential solution to the worldwide food crisis. The use of plants to remove toxins from the soil, such as heavy metals, trace elements, organic chemicals, and radioactive substances. It also explains how nanoparticles are becoming a popular method of desalination and it also faces the environmental challenges for the protection of plants.

Design and application of impact limiter for a spent fuel transport cask

As a key component of the spent fuel cask, the impact limiter can avoid the leakage of radioactive substances caused by the destruction of the container during the transport process and ensure the safe transport of nuclear spent fuel. In order to design a impact limiter that meets the engineering requirements, the effect of impact limiter size on the damping effect of the transport container was studied. The dispersity of wood compressive strength was obtained by wood compressive strength test. The 9m over center of gravity angle drop analysis of the transport container was carried out using the finite element method, and the 9m over center of gravity angle drop test was also carried out. The container acceleration and impact limiter deformation obtained by the test were consistent with the simulation results. The impact limiter of the cask is reasonably designed and can provide shock absorption and cushioning to the transport container. Generally speaking, the larger the size of the impact limiter, the more energy it absorbs but the damping effect decreases after its size exceeds a certain point. The simulation results show that when the energy absorption of the impact limiter is sufficient, the cushioning effect of wood with low compressive strength is better and the effect of wood compressive strength dispersity should be fully considered in the design.