Hazardous Processes Research Articles

Study on the Thermal Safety of 3,7‐Dinitro‐1,3,5,7‐Tetraazabicyclo[3.3.1]nonane Synthesized by Nitrolysis of Hexamine

AbstractThe thermal flow curves of the nitrolysis for the synthesis of 3,7‐dinitro‐1,3,5,7‐tetraazabicyclo[3.3.1]nonane (DPT) from hexamine in the presence of different amounts of acetic anhydride were obtained using reaction calorimetry. The maximum heat release rates during the feeding process, the corresponding maximum adiabatic temperature rises, and the Maximum Temperature of the Synthesis Reaction (MTSR) were determined, respectively. The thermal stability of the reaction product DPT and the reaction mixture was analyzed, and data on their thermal decomposition characteristics were obtained. The thermal decomposition kinetic model was utilized to simulate the stability under adiabatic conditions. TD24 (The temperature corresponding to the time required to reach the maximum reaction rate under adiabatic conditions for 24 hours) of the reaction mixture was calculated as 69.65°C. According to the thermal hazard parameters of the reaction, the process's hazard level under various acetic anhydride addition conditions was determined to be level 5 using the cooling failure scenario method.

Susceptibility of hydraulic structures to internal erosion: modeling of suffusion process

Internal erosion is a primary cause of hydraulic structure failure, manifesting as two key phenomena: piping erosion and suffusion. These processes differ in their geometrical and hydraulic boundary conditions, resulting in varying levels of failure risk. Piping erosion is the more hazardous and rapid process, often leading to immediate failure if not promptly addressed. In contrast, suffusion gradually alters the permeability of the medium, potentially culminating in failure after a prolonged period of development. In this study, we propose a model for suffusion based on Darcy’s law, Papamichos' erosion law, and Einstein's viscosity evolution relation. The model describes the temporal evolution of the average porosity in the porous medium, the concentration of eroded particles in the fluid, and the mass of particles eroded, while highlighting the impact of hydraulic and mechanical parameters, such as the erosion coefficient and maximum porosity, on this evolution. The numerical solution is obtained using the finite difference method, with the sample discretized into elementary layers. For discretization, an explicit off-centered scheme was adopted. The simulation results reveal that suffusion is strongly influenced by soil hydraulic and mechanical parameters, particularly the erosion coefficient (λ) and final porosity (Ømax).

Coal-Mine Water-Hazard Risk Evaluation Based on the Combination of Extension Theory, Game Theory, and Dempster–Shafer Evidence Theory

Due to the complex hydrogeological conditions and water hazards in coal mines, there are multiple indexes, complexities, incompatibilities, and uncertainty issues in the risk evaluation process of coal-mine water hazards. To accurately evaluate the risk of coal-mine water hazards, a comprehensive evaluation method based on extension theory, game theory, and Dempster–Shafer (DS) evidence theory is proposed. Firstly, a hierarchical water-hazard risk-evaluation index system is established, and then matter-element theory in extension theory is used to establish a matter-element model for coal-mine water-hazard risk. The membership relationship between various evaluation indexes and risk grades of coal-mine water-hazard risk is quantified using correlation functions of extension set theory, and the quantitative results are normalized to obtain basic belief assignments (BBAs) of risk grades for each index. Then, the subjective weights of evaluation indexes are calculated using the order relation analysis (G1) method, and the objective weights of evaluation indexes are calculated using the entropy weight (EW) method. The improved combination weighting method of game theory (ICWMGT) is introduced to determine the combination weight of each evaluation index, which is used to correct the BBAs of risk grades for each index. Finally, the fusion of DS evidence theory based on matrix analysis is used to fuse BBAs, and the rating with the highest belief fusion result is taken as the final evaluation result. The evaluation model was applied to the water-hazard risk evaluation of Sangbei Coal Mine, the evaluation result was of II grade water-hazard risk, and it was in line with the actual engineering situation. The evaluation result was compared with the evaluation results of three methods, namely the expert scoring method, the fuzzy comprehensive evaluation method, and the extension method. The scientificity and reliability of the method adopted in this paper were verified through this method. At the same time, based on the evaluation results, in-depth data mining was conducted on the risk indexes of coal-mine water hazards, and it was mainly found that 11 secondary indexes are the focus of coal-mine water-hazard risk prevention and control, among which seven indexes are the primary starting point for coal-mine water-hazard risk prevention and control. The groundwater index in particular has the most prominent impact. These results can provide a theoretical basis and scientific guidance for the specific water-hazard prevention and control work of coal mines.

Impact of hydrogeology factors on geotechnical conditions of the heritage Kyiv-Pechersk Lavra Monastery complex: Lessons from three decades of monitoring

Abstract The architectural ensemble of the Kyiv-Pechersk Lavra monastery located in the city of Kyiv on the Right Bank of the Dnipro River, which represents historical and cultural heritage of world significance, suffers from a wide range of hazardous geological processes. The review and analysis of data of the long-term (since the 1990s) groundwater monitoring studies of the Kyiv-Pechersk Lavra shows that hydrogeological hazards caused by a complex combination of natural and anthropogenic factors (as well as sometimes by engineering miscalculations) have led to a significant number of emergency situations that threaten the heritage architectural monuments. Monitoring data illustrate a wide range of hydrogeological hazards (flooding, subsidence, landslides, suffusion), and emphasize the importance of consideration of hydrogeological aspects for safeguarding architectural monuments in the urbanized context. The paper also summarizes experience in engineering measures aimed at mitigating of hydrogeological hazards and discusses the pending research tasks

Investigating the Use of Natural Hydrophobic Deep Eutectic Solvents for Extracting Carotenoids from Food and Food By-products

Abstract In today’s food industry, the demand for sustainable methodologies in producing health-promoting natural products is rising. Traditional extraction techniques are increasingly deemed unreliable due to environmental concerns. To address these challenges, the scientific community has developed Green Chemistry , a specialized branch that aims to minimize or eliminate hazardous processes and substances in industrial applications. One promising and eco-friendly alternative emerging from Green Chemistry is the use of NaDESs which are prepared with natural components, generally recognized as safe (GRAS), and offer an environmentally benign option for various industrial processes. They are characterized by their biodegradability, low toxicity, and ability to be tailored for specific applications, making them an ideal choice for green extraction methods. In this context, NaHDESs have shown significant potential as extracting media for bioactive compounds, particularly carotenoids, from food and food by-products. Carotenoids, known for their antioxidant properties and health benefits, are highly sought after in the food and nutraceutical industries. Traditional extraction methods often rely on organic solvents, which pose environmental and health risks. In contrast, NaHDESs offer a safer and more sustainable alternative. This study explores the definition, properties, and applications of NaHDESs, with a particular focus on their use in extracting carotenoids. By examining various food and vegetable by-products, the research aims to evaluate the solvent’s efficiency and effectiveness in this application. The findings could pave the way for eco-friendly extraction techniques in the food industry, aligning with the principles of Green Chemistry and addressing the growing demand for natural and health-promoting products. Information © The Author 2024

A single-layer compton camera for nuclear decommissioning: An improved back-projection algorithm

The decommissioning of nuclear facilities, a critical and hazardous process due to radiation exposure, necessitates the advancement of radiological measurement techniques concerning safety and efficiency. This study presents an optimized back-projection method, integrating a novel single-layer Compton camera and 3D camera setup with the Timepix3 readout chip to improve the precision and efficiency of gamma-ray source localization in decommissioning scenarios. Implementing ‘twin addition’ and ‘twin multiplication’ techniques addressed data ambiguities that arise from event selection in the Compton camera, enhancing the reliability of localization. Introducing a zoom function significantly improved computational efficiency, achieving 163 times faster computation times without sacrificing accuracy. Our method demonstrated enhanced precision with a median angular error of 1.41°, outperforming traditional methods and showing competitive advantages over state-of-the-art technologies, including the Caliste-HD detector. The feasibility of integrating this methodology onto mobile robotic platforms suggests a promising avenue to minimize human radiation exposure and optimize decommissioning tasks, ensuring safer and more effective nuclear facility decommissioning.

Hydrophobic modification of biomass chitosan for treatment of oily wastewater and its demulsification mechanism

Traditional demulsifiers are commonly produced using raw materials like ethylene oxide and propylene oxide, which deplete significant petroleum resources and involve hazardous and complex manufacturing processes. In this investigation, a hydrophobically modified chitosan (HMC) was synthesized by grafting dodecyl diethanolamine onto natural chitosan to facilitate the separation of O/W emulsions. Characterization of HMC was conducted using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance hydrogen spectroscopy (1H NMR) and scanning electron microscopy (SEM). The demulsification efficacy of HMC was assessed through a bottle test in an O/W emulsion containing 0.2 % crude oil. Results showed that at a HMC dosage of 40 mg/L, the light transmission (WT) and oil removal efficiency (WR) of the resulted water phase were 93.4 ± 0.8 % and 99.8 ± 0.1 %, respectively. Furthermore, the competitive adsorption between natural surfactants and HMC at the interface was investigated using interfacial tension (IFT), three-phase contact angle (CA), droplet coalescence time (CTA), and interfacial film substitution. A potential demulsifying mechanism was also proposed, emphasizing HMC’s hydrophilic core and dispersed hydrophobic alkyl chains that enable rapid diffusion to the oil–water interface, replacing interfacial active components to induce demulsification by destabilizing the composite film. The advantages of HMC demulsifier over commercial demulsifiers lie in its superior environmental benefits, diverse range of sources, higher efficiency, and outstanding demulsification performance.

Scientific-Practical Enhancement Principles for the Long-Term Stability of Cultural Heritage Objects through a Multi-Component Underground Space Analysis

This article presents approaches for enhancing engineering-geological and geotechnical research for the restoration and reconstruction projects of cultural heritage objects in St. Petersburg’s historical center. According to the Venice Charter, an interdisciplinary approach is recommended for developing a preservation program for cultural heritage objects. The authors consider the underground space as a multi-component system, where soils are a host medium for underground water with specific composition, complex physicochemical and biochemical conditions, the presence and vigorous activity of microorganisms, gases of various origins, and underground bearing and enclosing structures. The last of these components is crucial for the long-term stability of historical and cultural objects, as they interact in complex with water-saturated soils and microorganisms. This approach is not to be found in Russian cultural heritage preservation regulations. In engineering-geological and geotechnical research, multi-component underground space should be studied at the regional, local, and object levels. Assessing redox conditions in the underground environment is crucial for understanding the state of its components. Moreover, this can trigger hazardous processes such as changes in the stress–strain state and unconsolidation of the soil layer due to the generation of low-solubility gases and biocorrosion of ancient and modern building materials, causing premature destruction. Recommendations are provided for carrying out engineering-geological and geotechnical research based on cultural heritage objects, considering the multi-component underground space and features of its geoenvironmental state due to the long-term contamination and transformation of its components.

Observation and modelling of infragravity waves at a large meso-tidal inlet and lagoon

The role of infragravity waves (IG waves) in beach and dune erosion or in flood hazard has been extensively studied on open beaches. In contrast, the detailed characterization of IG waves and their contribution to the Total Water Level (TWL) along the shore of inlets received little attention so far. In such environment, there is a real lack of in situ observations of waves and hydrodynamics conditions at appropriate spatial and temporal coverage to study the role of infragravity (IG) waves (long waves of frequency typically ranging between 0.004 Hz and 0.04–0.05 Hz) on coastal hazards. This contribution is based on field observations collected at the Arcachon Lagoon, a shallow semi-enclosed lagoon connected to the ocean by a large tidal inlet, located in southwest France. Analyses combine observations made at several locations during storm events within the inlet and the lagoon with numerical simulation with the XBeach surfbeat model to explore the spatial variability of IG waves and simulate observed, historical, and idealized storm conditions. The results show that IG waves are substantial during typical winter storms at the inlet and range from Hm0 = 0.8 to over 1 m across the ebb delta and about 0.4–0.6 m in the inner part of the inlet. At the lagoon entrance, IG waves remain substantial (about 0.1–0.2 m) and decrease to a few centimeters at the lagoon shore. The spatial variability and magnitude of IG waves along the inlet coast, simulated for the historical storms, are quite comparable to those observed during classical winter, and do not increase linearly with offshore wave energy. However, both observations and simulations reveal local amplifications of IG waves in the inner part of the inlet, especially along the sheltered coast were IG waves dominate the variance of free surface elevation, reaching about 0.6–0.7 m during common storms and more than 1 m for an extreme storm scenario. A numerical experiment indicates that IG wave reflection from one coast to the other contributes up to 35–40% of the measured IG wave height at a hot spot located along the sheltered coast. Finally, the contribution of IG waves to TWL at the shore on both sides of the inlet has been estimated to be about 0.4–0.6 m for a common storm and 0.6–0.9 m for an extreme scenario, locally peaking at 0.74 and 1.1 m respectively and overpassing the contribution of wave-induced setup. This work provides new insights into the contribution of IG waves to TWL and its implications for overtopping flooding hazard and overwash processes at large inlets, highlighting the need to consider IG waves in Early Warning Systems or hazard mapping for flood prevention plans in these environments.

Zoning of the north-eastern part of Ufa according to the development of hazardous geological processes

Zoning of the north-eastern part of Ufa according to the development of hazardous geological processes

Working conditions and health effects of workers in a microware manufacturer of medical furniture, Maracay 2019

The present study aimed to determine the working conditions and health effects of the workers of a medical furniture manufacturing microenterprise. For this purpose, a quantitative and descriptive research was carried out, applied to 6 workers, the data collection technique was based on non-participant structured observation to know the work process and a structured interview in which the guide questionnaire was applied Colombian technique 450 to identify risk factors, their level and acceptability; To recognize the health effects, the questionnaire on risks and damages by Pere and Laurent was applied with the body diagram of pain. The hazardous work processes identified were: inadequate lighting, sharp objects, moving machines and tools, particle projection, welding smoke, wood dust, vibrations, gases and vapors, lifting and transporting loads, inappropriate positions. The risk factors identified were: physical and chemical with a level of risk III being acceptable, as well as dysergonomic and mechanical with a level of risk II being not acceptable, likewise the health conditions identified were injuries by accident, eye and respiratory problems and muscle aches, the most frequent areas of pain being legs, neck and lumbar region

Climate sensitivity of natural hazards processes in mountain regions: A fuzzy logic approach

Natural hazard processes, as an inherent component of mountain environments, react sensitively to global warming. The main drivers of these changes are alterations in the amount, intensity or type of precipitation, glacier melting, or thawing of permafrost ice. The hazard responses can involve a change in hazard intensity or frequency (increasing or decreasing), a shift in their location or, a shift from one type of hazard to another. As climate change impacts vary in space and time, this variability must be considered when planning measures to protect populations and infrastructure from hazardous processes. To support this, we developed a method for assessing the climate sensitivity of small individual rock releases and larger rockfall processes. The method is based on a fuzzy logic approach and uses highly resolved climate scenario data, allowing application on a regional or even larger scale.The application in a study area of 700 km2 in the central Valais (Switzerland) shows that the impacts of climate change on natural hazard processes can vary quite substantially across small spatial scales. Generally, an increase in rockfall frequency and magnitude is simulated under future warming scenarios, especially at higher altitudes. However, at lower elevations and on south-exposed slopes, a decrease in freeze-thaw cycles leads to a decrease in material availability. This knowledge is essential in discussions of how climate change should be considered in hazard and disaster management.

Residential building and sub-building level flood damage analysis using simple and complex models

AbstractFlood damage assessment is critical for optimal risk management investments. Damage models evaluate physical damage or monetary loss from direct building exposure to flood hazard processes. Traditional models represent a simple relationship whereby physical damage increases with water depth. More complex models offer an improved understanding of vulnerability, analysing interactions between multiple hazard and exposure variables that drive damage. Our study investigates whether increasing model complexity and explanatory damage variables improves prediction precision and reliability at residential building and sub-building (component) levels. We evaluate simple and complex empirical univariable and multivariable models for flood damage prediction. The Random Forest algorithm learned on multiple hazard and exposure explanatory variables outperformed linear and non-linear univariable regression approaches. Random Forest model predictive precision was highest when learning was limited to water depth and several important explanatory damage variables (flow velocity, area and floor height). Component damage models demonstrated high predictive precision for internal finishes and services. Precision reduced for structure and external finishes as damage samples for model learning were limited. High performing but complex multivariable models require further spatio-temporal transfer investigation to determine opportunities for accurate and reliable object-specific flood damage prediction in data scarce locations.

Hierarchical Structure of Small–Medium Enterprise Accidents Contributing to Legal Proceedings Resulting in Judicial Verdicts Using Interpretive Structural Modeling

Abstract Aim: The present study aims to identify and model factors influencing accidents in small–medium enterprises based on judicial orders. Methods: This study was conducted in two primary phases. The first phase involved analyzing legal documents related to work-related accidents to extract factors influencing accidents in SMEs. In the second phase, interpretive structural modeling (ISM) was employed to hierarchically model these factors and understand their relationships using ISM Excel base software. Ten experts from various Iranian universities and industrial companies participated in the study, contributing to the completion of matrices used in the ISM model. Results: In this study, 10 primary factors contributing to accident occurrences in SMEs were identified and categorized into three main groups: Individual factors related to the incident (comprising five subfactors), organizational factors (comprising three subfactors), and conditional factors (comprising two subfactors). The subsequent phase involved modeling the identified factors using the ISM technique. The results revealed that three factors – training, equipment-related factors, and hazardous processes or harsh environments – were placed at level 2, designating them as the key factors influencing accidents. Conclusion: The current research demonstrates that in SMEs, conditional and organizational factors like equipment shortcomings, hazardous processes, and insufficient training for workers are key factors in accident occurrences within these systems. Consequently, by controlling these factors, improvements in their safety conditions can be pursued.

Socio-psychological factors explaining public engagement and support for drought disaster risk management

Droughts have become a critical high-impact hydro-meteorological disaster and are projected to become more extreme in the near future. The Iberian Peninsula is unarguably considered a pronounced hot spot for drought. Worrisome projections for drought risk come to emphasize the urgency of building drought-resilient societies, through integrated risk management processes that bring together all societal spheres, including lay citizens. However, citizens remain disengaged from climate risk and adaptation processes. Therefore, it is critical to understand how societies respond to climate-related hazardous processes, such as drought, and to determine the predictors of citizens' engagement in disaster risk management. To respond to this research need, this study sought to explore citizens' preferences for drought management policies and to ascertain the psychosocial predictors of citizens' willingness to take action towards drought and support for drought risk management. A cross-sectional study was implemented, in which 401 Portuguese participants enrolled in a survey questionnaire measuring predictor variables of citizens' willingness to take action and support for drought risk management. A robust set of statistical analysis was implemented, mainly based on structural equation modelling. Results demonstrate that citizens tend to prefer low-cost measures and policies that due not imply personal heightened burden, at a financial and behavioral level. Moreover, personal experience with drought, risk perception, perceived urgency and emotional states play a critical role in citizens’ engagement and support for disaster risk management. Findings are discussed in light of their theoretical and practical implications, particularly for risk communication and for risk management policymaking.

An overview of the preparation and implementation of the safety case in support of the 2nd JET deuterium–tritium experiment

An overview of the preparation and implementation of the JET 2nd deuterium-tritium experiment (DTE2) safety case is presented. The safety case regime, developed by UKAEA for fusion applications to demonstrate compliance with relevant regulations, and its implementation on UKAEA sites is outlined. The hazard assessment process and details of the methodology applied to assess key JET fault scenarios are provided. An outline of key inventories, their composition, and applied factors for consequence and risk assessment are discussed. The consequences resulting from key fault sequences, the designation of appropriate safety measures and the associated risks are summarised and compared against basic safety limits and objectives. Finally, some of the lessons learned from DTE2 following implementation are discussed.

Development of a resilience safety culture model for the hazardous materials processing industry

Many previous cases have demonstrated that hazardous materials processing industry (HMPI) accidents always result in huge losses and HMPI companies which suffer accidents are difficult to quickly restore. This has demanded an effective way to solve the two problems. Resilience safety culture (RSC) combines conventional safety culture and resilience engineering. It aims at giving an organization the abilities of continually operating or timely recovering during or after a major unexpected event. RSC fits the safety demands of the HMPI well. The present study develops a RSC model for the HMPI. Firstly, through literature review, 12 model elements with 16 hypothesized relationships are developed. These hypothesis are then tested by 618 samples with structural equation modelling. Finally, an HMPI RSC model with 12 elements and 12 relationships is established. Model validity is verified by a comparison study on the proposed model and two existing models with the fuzzy analytic hierarchy process.

An in silico investigation of the toxicological effects and biological activities of 3-phenoxybenzoic acid and its metabolite products

We aimed to elucidate the toxic effects and biological activities of 3-phenoxybenzoic acid (3PBA) and its metabolite products. Numerous in silico methods were used to identify the toxic effects and biological activities of 3PBA, including PASS online, molecular docking, ADMETlab 2.0, ADMESWISS, MetaTox, and molecular dynamic simulation. Ten metabolite products were identified via Phase II reactions (O-glucuronidation, O-sulfation, and methylation). All of the investigated compounds were followed by Lipinski’s rule, indicating that they were stimulants or inducers of hazardous processes. Because of their high gastrointestinal absorption and ability to reach the blood-brain barrier, the studied compounds’ physicochemical and pharmacokinetic properties matched existing evidence of harmful effects, including haematemesis, reproductive dysfunction, allergic dermatitis, toxic respiration, and neurotoxicity. The studied compounds have been linked to the apoptotic pathway, the reproductivity system, neuroendocrine disruptors, phospholipid-translocating ATPase inhibitors, and JAK2 expression. An O-glucuronidation metabolite product demonstrated higher binding affinity and interaction with CYP2C9, CYP3A4, caspase 3, and caspase 8 than 3PBA and other metabolite products, whereas metabolite products from methylation were predominant and more toxic. Our in silico findings partly meet the 3Rs principle by minimizing animal testing before more study is needed to identify the detrimental effects of 3PBA on other organs (liver, kidneys). Future research directions may involve experimental validation of in silico predictions, elucidation of molecular mechanisms, and exploration of therapeutic interventions. These findings contribute to our understanding of the toxicological profile of 3PBA and its metabolites, which has implications for risk assessment and regulatory decisions.

Landslide Detection using IoT

The paper aims to decrease the number of accidents that occur on curved roadways. To do this, a warning LCD Display that displays as a vehicle approaches from the other side of the bend serves as a message to the driver. The IR transmitter and receiver sensor, which is connected to the Arduino Uno microcontroller, is used to detect the vehicle. And Motor operated gates are fixed upon each sides for free passage of vehicles from one side to other side. On the winding roads in the ghat portion, this might save thousands of lives. By implementing a new technique, they come up with a plan to prevent accidents after determining their causes and effects. Two IR sensors make up the new method, which alerts the vehicle on the opposite road. Landslide is one of the hazardous and critical geographical process, which damages to civil infrastructure and property as well as causes loss of life. This paper is an attempt with regard to the expansion of a landslide susceptible approach by using Accelerometer Sensor. And Rain Sensor is used for detecting heavy rainfall. Upon detecting the landslide condition or Heavy Rains it warns on display as a message and closes gates on either sides of ghat till road condition gets normal

Recent Jishishan earthquake ripple hazard provides a new explanation for the destruction of the prehistoric Lajia Settlement 4000a B.P.

The Jishishan Ms 6.2 earthquake occurred at 23:59 on December 18, 2023 in Gansu Province, China. We conducted a field survey to assess the hazards and damages caused by the earthquake and its associated geo-activities. Subsequently, we organized a seminar to discuss the possible causes of the destruction of a prehistoric site—Lajia Settlement—dated back to four thousand years B.P. and located only several kilometers away from the epicenter of the Jishishan earthquake. The Jishishan earthquake was unique for its hazard and disaster process, which featured ground shaking and a series of complex geological and geomorphological activities: sediment and soil spray piles, liquefaction, collapse, landslide, and mudflow along water channels. We define this phenomenon as the Jishishan earthquake ripple hazard (JERH). The most recent evidence from the JERH suggests that a prehistoric earthquake similar to the JERH, instead of riverine floods or earthquake-induced landslide dam outburst flood, as previously hypothesized, destroyed the Lajia Settlement.