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N-butanol is well known to be a flammable and harmful liquid that is a potential threat to human health and property. Therefore, it is important to monitor the concentration of n-butanol in the surroundings. The need for highly efficient toxic gas detection is urgent and has been driving the research on gas sensors for practical applications. Molybdenum disulfide (MoS2) has been attracting significant interest for gas detection at room temperature. Herein, we report biofunctionalized magnetic nanoparticles incorporated MoS2 for sensing n-butanol. The biosynthesized magnetite nanoparticles (CT-Fe3O4) were synthesized by the addition of Cinnamomum Tamala (CT) leaf extract, and subsequently, the nanocomposite was synthesized using a hydrothermal method. Highly sensitive sensors based on MoS2-CT-Fe3O4 were fabricated and tested for sensing different concentrations of n-butanol. The nanocomposites showed a good sensing performance (Δ R/Rair %) of 72% towards 20 ppm of n-butanol, indicating the potential use of MoS2-CT-Fe3O4 nanocomposite for sensing n-butanol at room temperature. [ABSTRACT FROM AUTHOR]

Growing market demands on portable electronics, electric vehicles, and energy storage system calls for the development of high‐energy density lithium (Li) batteries. Li metal is considered as a promising anode material owing to their high capacity and low electrochemical potential. However, high reactivity of Li metal with conventional flammable liquid electrolytes easily forms Li dendrites, which may cause short‐circuit and even catching fire, obstructing the wide application of Li metal batteries. Although non−/less‐flammable solid electrolytes have replaced the conventional liquid electrolytes, solid‐state Li metal batteries (SSLMBs) suffer from lower Li+ conductivities, chemical/electrochemical incompatibilities toward Li metal, and inhomogeneous Li+ flux at the interfaces. Therefore, many researchers have devoted themselves to solve these problems. For a better understanding on the current issues and recent advances, this article provides (1) a review on various solid electrolytes with high Li+ conductivity and their interfacial issues in SSLMBs, and (2) recent progress in stabilization of the interface between the Li node and solid electrolytes, including an electrolyte modification (e.g., composition, additives) and introduction of an interlayer. [ABSTRACT FROM AUTHOR]

Lithium‐ion batteries (LIBs) have dramatically transformed modern energy storage, powering a wide range of devices from portable electronics to electric vehicles, yet the use of flammable liquid electrolytes raises thermal safety concerns. Researchers have investigated several ways to enhance LIB's fire resistance. Fire retarding molecules functions through cooling effects, scavenging radicals, and forming protective barriers. Incorporating fire‐suppressing molecules within the LIBs aims to delay or mitigate thermal runaway scenarios, reducing the risks of fires or explosions. Achieving an optimal balance between safety and performance is a major obstacle in the design of intrinsically safer LIBs. Therefore, it is important to consider their effects on LIB's performance, long‐term stability, and environmental impact. To overcome these challenges, collaborative research efforts among academia, industry, and regulatory sectors are necessary. This article reviews state‐of‐the‐art literature associated with LIBs safety or even fire mitigation by introducing solid‐state or quasi‐solid‐state electrolytes as well as modified liquid electrolytes. Moreover, the effectiveness of various strategies in making LIBs intrinsically safer is critically evaluated with an emphasis on fire retardants followed by shedding some light on the remaining challenges. [ABSTRACT FROM AUTHOR]

Solid‐state electrolytes (SSE) exhibit great promise in enhancing the safety of Li metal batteries by replacing flammable liquid electrolytes. However, the practical application of SSE is hampered mainly due to the poor electrode–electrolyte interface, low ion conductivity, and inferior electrochemical stability. Herein, superior nonflammable solid polymer electrolytes are elaborately designed by in situ encapsulating succinonitrile (SN)‐based deep eutectic solvent (DES) into the ethoxylated trimethylolpropane triacrylate (ETPTA) matrix (DES‐ETPTA). Benefiting from strong polarity and high anti‐oxidation capability, as‐prepared DES‐ETPTA electrolyte shows high ionic conductivity (9.55 × 10−4 S cm−1 at 30 °C), high Li+ transference number (0.68), and good electrochemical stability. As a result, the assembled LiFePO4 || Li full cells based on the designed DES‐ETPTA electrolyte deliver a high reversible capacity and capacity retention at −10 °C and room temperature. Furthermore, considering the compatibility with high‐voltage layered oxide cathode, the electrochemical stability of the ETPTA is further improved through the decoration of cyanoacrylate (CA) with strong electron‐withdrawing characteristic of C≡N. Consequently, the constructed 4.5 V LiCoO2 || Li full cells using DES‐ETPTA‐CA electrolyte deliver a high reversible capacity of 144 mAh g−1 and a superior retention rate of 93% after 200 cycles at 0.5 C. This work paves a new pathway to design high‐safety and high‐voltage solid polymer electrolytes for lithium metal batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Composite polymer electrolytes were successfully prepared using solution casting and electrospinning method. • LaFeO 3 increases the amorphous regions of poly(vinylidene fluoride hexafluoropropylene) enhancing the ionic conduction. • Solution casted electrolyte with 5 wt% LaFeO 3 shows very low polarization voltage and excellent electrochemical compatibility against lithium metal. • Solid-state battery using solution casted electrolyte with 5 wt% LaFeO 3 shows superior cycling stability and electrospun electrolyte with 5 wt% LaFeO 3 exhibits better rate performance. Composite polymer electrolytes (CPEs) are a promising alternative to flammable conventional liquid electrolytes for high-safety lithium-ion batteries. Establishing low-cost filler that enhances the amorphous nature of polymer in the CPEs and exhibits efficient Lewis acid-base interaction between fillers and anions of lithium salt, leading to improved dissociation of salts for enhanced conduction, is indispensable. In this work, for the first time, we construct a solid composite polymer electrolyte of poly(vinylidene fluoride hexafluoropropylene) embedded LaFeO 3 (LFO) particles prepared by solution casting and electrospinning methods and study their performances. The 5 wt% LFO filler embedded CPE made by means of solution casting and electrospinning methods exhibited the highest ionic conductivity of 5.9 × 10-4 and 1.49 × 10-3 S cm−1 at room temperature and electrochemical stability window up to 4.6 and 4.45 V, respectively. Further, as-assembled solid-state lithium-ion batteries using electrospun CPE showed an initial discharge capacity of 166 mAh/g at 0.1C-rate and solution-casted CPE showed excellent cycling stability with 98.6 % capacity retention at 0.3C-rate even at 50th cycle. Such excellent performance originated from the introduction of the LFO particles as filler into the polymer matrix to enhance the ionic conductivity, mechanical strength and lithium metal compatibility of the resulting CPEs. [ABSTRACT FROM AUTHOR]

Storage tank fire can pose great threats to life and environment as it can cause strong radiant heat, fast-spreading flame, and destructive explosion. In this research, a 1.5 m-diameter circular steel pan is used to simulate the full surface fire of a storage tank in an industrial park. A self-built fire-extinguishing system gently releasing foam at the rate of 11.4 L/min was applied for the evaluation of the effectiveness of different types of foam of extinguishing diesel/methanol pool fires. Experiments were conducted to analyze the temperature increases of fires after releasing different types of foam. In this research, the nondimensional average temperature 0.85 and 0.71 regard as the fire extinguishing temperatures of methanol and diesel fuel, respectively. Over the spreading process, the increase in foam spreading length over time still follows the power law. The fastest flow velocity of 6% FP/AR in methanol pool fire and 6% Synthetic foams in diesel pool fire was 0.0136 m s −1and 0.044 m s −1, respectively, with a foam application rate of 11.4 L/min. The results show that, in the methanol pool fire, the cooling effect of the foam is ranked as FP/AR > AFFF > AFFF/AR > S > FP > S/AR. And the cooling effect of foam for diesel is ranked as S > S/AR > AFFF > AFFF/AR > FP > FP/AR. Foam's cooling impact is especially notable in diesel pool fires. As for methanol pool fires, the foam extinguishing mechanism is mainly based on the "anti-soluble film" effect, which quickly forms a covering layer on the surface of the flammable liquid, seperating the flame from heat feedback and inhibiting the generation of flammable vapors, insulating itself against the air and ultimately asphyxiating the fire. [ABSTRACT FROM AUTHOR]

[Display omitted] Nanoparticle-stabilized foams are extremely stable, and flame retardant inorganic nanoparticles should be able to add sealing capacity of firefighting foams on flammable liquid fuels, and hence enhance fire extinguishment performance on liquid fuel fire. In practice, how do flame retardant nanoparticles resist the destructive effect of oil molecules on foam and tune foam properties? We have prepared a nanoparticle-enhanced foam comprising of hydrocarbon surfactant, short-chain fluorocarbon surfactant, and nanoparticles. The interactions among nanoparticles and surfactant molecules were characterized by using dynamic surface tension and conductivity. Stability, rheology, and oil resistivity on liquid fuel of the nanoparticle-enhanced foam were evaluated systematically. Fire suppression effectiveness of the foams was verified based on a standard experiment. Foam stability and oil resistivity were enhanced due to self-assembled network structures formed by jammed aggregates composed by nanoparticles and surfactants in Plateau borders and bubble films, providing structural recoverability and enhanced viscoelasticity within foam. Foams containing nano-SiO 2 , nano-CaCO 3 , nano-Al(OH) 3 , and nano-Mg(OH) 2 show difference in fire extinguishment due to different ability to enhance foam properties. Foam containing nano-Al(OH) 3 shows the strongest adaptation and could shorten fire extinguishing time by 2 times and prolong burn-back time by 2.3 times compared with commercial product. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Acetone, a flammable and volatile liquid, is toxic and can affect human well-being. Additionally, its presence in exhaled air can indicate the state of human respiratory health. Therefore, the investigation of an acetone gas sensor holds significant urgency in the realm of scientific research. Metal-organic frameworks (MOFs) exhibit significant promise in the field of gas detection due to their extensive surface areas, remarkable porosity, and the inclusion of unsaturated metallic sites. The study conducted the preparation of ErFeO 3 /α-Fe 2 O 3 nanocomposites through impregnation and oxidation roasting methods. EF21 (M Er (NO 3) 3 ∙ 6 H 2 O :M MIL-100(Fe) = 2:1) exhibited a large surface area of 43.7 m2/g and a high abundant oxygen vacancy of 12.5 %. Gas sensing experiments revealed that the EF21-based gas sensor exhibited a strong response of 55 towards 100 ppm acetone, with a low detection limit of 2 ppm (S = 3.3). Notably, the sensor demonstrated excellent selectivity towards acetone over other volatile organic compounds (e.g., ethanol, methanol, ammonia, ether, and toluene) in gas selectivity tests. Moreover, the EF21-based gas sensor maintained its responsiveness to acetone even under high relative humidity conditions (RH:90 %, S = 27) and demonstrated stability over a 15-day long-term test. The study provided a comprehensive explanation of the gas sensing mechanism responsible for the enhanced performance observed in ErFeO 3 /α-Fe 2 O 3 through detailed analyses. [ABSTRACT FROM AUTHOR]

The risk of flammable dangerous liquids stored on the industrial premises escaping into the environment in the event of major industrial accidents must be minimized. Such a risk reduction result can be achieved by the use of safety barriers, such as a remediation bund area, which can retain, collect and store the released material. The careful determination of design parameters of this installation is of great importance. Therefore, this study–based on the analyses of applicability of existing guidelines (SPCC and HSNOCOP 47)—will propose a new sizing calculation methodology to design optimal and efficient remediation bund parameters, including the remediation bund wall height and distance between the remediation bund and the storage tank walls. The design parameters are defined by applying Toricelli's theorem and their practical compliance is tested using consequence analysis simulation software ALOHA 5.4.7 covering three possible major accident scenarios. As a result of the newly proposed methodology, the risk of overflow through the remediation bund wall can be excluded and higher effectiveness of the application of firefighting and technical rescue intervention activities can be ensured. The results of present research ultimately serve to prevent major industrial accidents and eliminate their possible harmful environmental impact. [ABSTRACT FROM AUTHOR]

[Display omitted] Due to their superior safety and stability, solid-state electrolytes (SSEs) are a promising alternative to flammable liquid electrolytes in lithium-ion batteries. However, the poor solid–solid contact at the SSEs/electrodes interface remains a significant challenge. To address this issue, inspired by spider silk, we develop a composite polymer electrolyte (SPLZO), which is highly adhesive due to the designed rich hydrogel bond network, containing a supramolecular poly (urethane-urea) (SPU), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12. The abundant hydrogen bonds mainly enabled inherently strong adhesion to ensure intimate electrolyte–electrode contact with low interfacial impedance. Besides, the soft polymer segments facilitate Li+ transport, and the hard components enhance the LiTFSI dissociation and accelerate Li+ motion, resulting in a high ionic conductivity of 1.67 × 10−4 S cm−1. The significantly improved interface contact and high ionic conductivity lead to a decent capacity and cycling performance of the fabricated solid-state lithium-ion batteries. Moreover, the designed SPLZO electrolyte exhibits remarkable deformability, and the flexible lithium-ion battery demonstrates outstanding mechanical flexibility and stability with negligible capacity loss when subjected to various dynamic deformations. This adhesive SSE design strategy opens new possibilities for promoting interfaces in solid-state batteries. [ABSTRACT FROM AUTHOR]

The object of this study is the process of liquid combustion in a spill, and the subject of research is the distribution of temperature along the wall and roof of a vertical steel tank that is heated under the thermal influence of a spill fire. The heat balance equation for the wall and roof of the tank with oil product was constructed. The assumption of a small thickness of the wall and roof of the tank relative to its linear dimensions makes it possible to move to two-dimensional differential equations of the parabolic type. The equations take into account the radiative heat exchange with the flame, the environment, the internal space of the tank, as well as the convective heat exchange with the surrounding air, the vapor-air mixture, and the liquid inside the tank. Using the methods of similarity theory, estimates of the coefficients of convection heat exchange of the outer surface of the tank with the surrounding air and the inner surface with the vapor-air mixture and liquid in the tank in the conditions of free convection were constructed. The application of the finite difference method for solving the heat balance equations has made it possible to derive the temperature distribution on the surface of the tank at an arbitrary moment in time. It is shown that the value of the coefficient of convection heat exchange of the liquid exceeds the corresponding value for the air-vapor mixture by (1÷2) orders of magnitude. As a result, the part of the wall located below the oil product level is heated to a temperature of (80÷230) °C depending on the viscosity of the liquid. This occurs despite the fact that the value of the mutual radiation coefficient reaches its maximum value at the lower part of the wall. From a practical point of view, this means that the part of the wall above the level of the oil product in the tank can reach dangerous temperature values, and it should be cooled first. The constructed model of tank heating also enables determining the limit time for the start of cooling of the tank [ABSTRACT FROM AUTHOR]

The object of this study is the properties of compressed air foam with the use of modified additives: its drainage time and expansion ratio. The main properties of compressed air foam that affect the effectiveness of fire extinguishing are its drainage time and expansion ratio. At the same time, a number of authors have confirmed that the introduction of chemically modified additives into the composition of water fire extinguishing substances makes it possible to increase the effectiveness of fire extinguishing. The problem to be solved was to determine the influence of five modified additives (N4)2HPO4, N4H2PO4, (N4)2СO3, K2CO3 and KCl in the concentration range of 1–5 % by mass on the expansion ratio and drainage time of the compressed air foam. The results showed that the content of additives (N4)2HPO4, N4H2PO4 and (N4)2СO3 in the aqueous solution of the foaming agent does not affect its expansion ratio within the given limits. On the other hand, with K2CO3 and KCl additives, it was not possible to obtain compressed air foam with a expansion ratio of 5–20, that is, their inefficiency in compressed air foam was noted. The characteristic dependence of the effect of (N4)2HPO4, NH4H2PO4 and (N4)2СO3 additives on drainage time has been determined. The greatest drainage time is characteristic of the K≈20 generation mode. The highest recorded drainage time index was established for N4H2PO4, namely 5.45 min; for (NH4)2HPO4 the drainage time was lower by 8 %; for (N4)2СO3 the drainage time was lower by 20 %. At the same time, with the use of (N4)2HPO4, N4H2PO4 and (NH4)2СO3, it is characteristic to obtain a foam with lower drainage time compared to foam of a conventional composition. Thus, for foam with a expansion ratio of K≈20, the drainage time of foam with NH4H2PO4 is lower by 17 %, with (NH4)2HPO4 by 23 %, and with (NH4)2СO3 by 33 %. The effect of reducing the drainage time of the foam can have a decisive role in reducing its effectiveness when used for extinguishing flammable liquids due to the extinguishing mechanism but is not decisive for extinguishing solid substances. Therefore, the fire-extinguishing effectiveness of compressed air foam with modified additives during the extinguishing of solid combustible materials in comparison with the conventional CAF composition requires further study [ABSTRACT FROM AUTHOR]

Flash point is an important parameter to determine the flammability properties of liquids. For this reason, determining the flash points of liquids is necessary for taking the necessary precautions for the storage and transportation of liquids. We propose that scattering parameters can be used to predict the flash points of flammable liquid mixtures. Therefore, in this study scattering parameters of various aqueous solutions were obtained using an antenna designed for this purpose and then the relationship between the flash points of the aqueous solutions and the scattering parameter was revealed by regression analysis. The results show that it is possible to predict the flash points of pure liquids and aqueous solutions from their scattering parameter measurement. [ABSTRACT FROM AUTHOR]

Flammable liquids typically adopted in chemical and industrial processes can be subjected to intense heat radiation due to nearby hot surfaces or fires. A second cascading event is then likely because the flash point can be easily reached and the surrounding environment can provide sufficient energy for ignition. Nevertheless, the flaming condition is not necessarily reached instantaneously if no direct (e.g., spark) ignition is present. Hence, a time to flaming, i.e., in the absence of an ignition source, is extremely relevant for the active and passive fire protection of flammable liquid, as the minimum time for intervention can be defined before developing a pool fire and for the correct evaluation of domino effects, in analogy with gas fires. In addition, a complete characterization of liquid behaviour under radiant heating is essential to guarantee safe operations, prevention measures, robust databases and optimized design. Therefore, this work reports the results for three liquid solvent representative classes of substances: i) hexane, ii) ethyl acetate, and iii) ethanol. A bench scale facility was adopted for the characterization of mass and energy aspects involving a pool fire of the investigated substances. Among the others, the ignitability and the intensity of the generated pool fires were evaluated experimentally in terms of mass burning rate, heat release rate, and combustion efficiency. Different boundary conditions were tested to identify the optimized set of conditions for a robust evaluation of the safety aspects of liquid. Results showed the most relevant trends in terms of ignitability of liquid species and combustion intensity during the pseudo-steady state regime of a pool fire. In addition, indications on the boundary conditions to be considered for a robust and consistent dataset were provided in this work. [ABSTRACT FROM AUTHOR]

For more than a century, smoke explosions have been documented in the fire research literature. Yet even with this long history, smoke explosions have received very little attention in the fire research community. The few review articles on unexplained explosions (overpressure events) have adopted the conventional names of smoke explosions, backdraft, smoke gas explosions or rapid fire progression. Anecdotal evidence from firefighters have shown a number of overpressure events that cannot be explained as a gas leak or flammable liquids ignition. In this study, experiments were conducted in a plywood lined compartment with a timber crib as a sustained fire source and the ignition source. The compartment had a single vent that was open for the entire time. After an extended period of burning, the flames detached from the crib, traveled around the compartment, and finally self-extinguished. Sometime after the flames self-extinguished, the compartment erupted in flames culminating in a large horizontal flame projecting more than 2 m from the vent opening. In this study, a consistent cycle that leads to an overpressure event has been identified. A total of 29 overpressure events were created in 13 experiments with many experiments experiencing multiple overpressure events. Gas species, compartment temperatures, vent velocities, and compartment pressure were all recorded during the experiments. Conditions in the compartment immediately prior to the overpressure event are reported. Having demonstrated that an overpressure event within a combustible compartment can be reproduced, future research is recommended to better quantify the conditions leading to an overpressure event. [ABSTRACT FROM AUTHOR]

In recent times, there has been significant enthusiasm for the development of all-solid-state Li-ion batteries. This interest stems from a dual focus on safety—addressing concerns related to toxic and flammable organic liquid electrolytes—and the pursuit of high energy density. While liquid electrolyte batteries currently constitute the vast majority of commercial cells, solid electrolyte batteries show great promise. In parallel with experimental research, computational models clarify several fundamental physics that take place throughout battery operations. Giving up on reviewing a broad screening of the existing literature, we set out to select here a few highly relevant models, emphasizing some fundamental conceptual advancements and offering an in-depth and critical insight into the current state of the art. The papers we selected aim at providing the reader with a tangible and quantitative understanding of how all-solid-state Li-ion batteries operate, including the different mechanisms at play and the mathematical tools required to model the pertinent physics and mechanics. [ABSTRACT FROM AUTHOR]

Predicting the entire thermal degradation process of solid combustibles infiltrated with flammable liquids is a challenge at present. In the current study, a novel artificial neural network (ANN) framework containing data preprocessing, data normalization and data transformation is proposed to predict the entire thermal degradation process of polymethyl methacrylate infiltrated with kerosene at three scenarios: (1) fixed kerosene mass fraction with various heating rates, (2) fixed heating rate with various kerosene mass fractions, and (3) various kerosene mass fractions with various heating rates. The entire thermal degradation process of scenario (1) can be accurately predicted using the ANN with 2‐4‐2‐1 topology. Using the data transformation formula exp(x1(1 + x2) to generate a new input variable based on temperature and kerosene mass fraction, a new ANN with 3‐4‐2‐1 topology can accurately predict the entire thermal degradation process of scenario (2). Two new input variables are generated using the data transformation formula 1/(1 + log((1 + x1)(1 + x2))) based on two data sets: (1) kerosene mass fraction and temperature, and (2) heating rate and temperature. The new ANN with 5‐4‐2‐1 topology can accurately predict the entire thermal degradation process at all three scenarios. The new ANN with Levenberg–Marquardt training function and Tanh activation function possesses the best prediction performance. Highlights: Data preprocessing can significantly improve the prediction accuracy of ANN.ANN with a suitable hidden layer structure has high prediction accuracy.The new ANN can predict the entire pyrolysis process in various scenarios.ANN with LM and Tanh has the highest prediction accuracy. [ABSTRACT FROM AUTHOR]

Foam extinguishing agents are crucial for the suppression of flammable liquid fires. Their thermal stability performance and heat insulation characteristics are critical indicators to evaluate the efficiency of the fire‐fighting foam. There have been some studies focused on exploring the behavior of fire‐fighting foams exposed to radiant heating. However, the decay mechanisms and heat transfer behaviors of the foam at the micro‐scale are still unclear and require further clarification. Therefore, in this study, the volume reduction coefficient, falling time of foam column height, and the temperature profiles of the foam layer under the thermal radiation environment of different conditions are discussed. The results indicate that the high temperature generated by the radiative heat flux will accelerate the collapse rate of the foam layer. The stability of the foam structure will be seriously damaged. There is a relationship between heat radiation intensity and foam attenuation coefficient. The empirical model for reflecting the fire‐fighting foam collapse process under the fire environment with high heat radiation flux is modified. Moreover, the average collapse rate and temperature difference gradient are used to characterize the thermal stability performance and heat insulation characteristics of the foam. Analysis of the micro‐scale foam structure parameters from the foam scans has revealed that the thermal stability performance and heat insulation characteristics of the foam are stronger when the surface tension of the foam is within the range of 17.4–20.4 mN/m. [ABSTRACT FROM AUTHOR]

There are a large number of low boiling point combustible liquids in petrochemical enterprises. The current national standards have no clear provisions on the fire extinguishing design parameters of low boiling combustible liquid storage tanks, and the ordinary foam fire extinguishing system cannot completely extinguish the fire. It is urgent to provide reliable fire extinguishing means for low boiling combustible liquid storage tanks. This article analyzes the difficulty of extinguishing low boiling combustible liquid fires based on existing engineering design and new fire extinguishing theories. The fire extinguishing methods such as fixed heptafluoropropane foam fire extinguishing system, fixed compressed air foam fire extinguishing system, semi fixed compressed air foam fire extinguishing system, mobile air foam fire extinguishing system and dry powder fire extinguishing system are discussed respectively, and corresponding fire extinguishing system solutions are provided according to the storage mode. Reflections are put forward on the problems and innovative points in the application of new fire extinguishing systems, in order to provide certain ideas for future fire protection design and the formulation of relevant standards, and to improve the safety of oil storage in petrochemical enterprises. [ABSTRACT FROM AUTHOR]

A series of fire tests were performed to study the effect of infiltration depth on the burning behavior and fuel residue of porous media bed soaked by liquid fuel. Ethanol was used as liquid fuel and quartz sand was used to naturally stack to form the porous media bed with different infiltration depths within the range of 60–180 mm. Burning rate, internal temperature of porous media bed, flame height, movement speed of fuel vapor zone, and fuel residue percentage was measured and analyzed. Results show that within current test scope, fuel mass loss rate in quasi stable period is negatively correlated with infiltration depth, and the relationship between mass loss rate and infiltration depth can be well characterized by power function. Quasi stable flame height also decreases gradually with the increase of infiltration depth. With the range of 78.5–79.2°C, the temperature growth retardation occurred inside sand bed, and sand bed was hence assessed as a distinct three-zone feature. The movement speed of vapor zone decreases linearly with the increase of infiltration depth, and the maximum measured value is about 0.041 mm/s. Axial temperature distribution of flame and plume can be well characterized based on McCaffery's plume relationship, but the length of continuous flame and intermittent flame zone is shortened to some extent. Within current test range, fuel residue percentage increases with the increase of infiltration depth and particle size, and maximum fuel residual percentage is at 5.29% in the case with 180 mm infiltration depth, which is obviously smaller than previous scholars' results. In addition to the depth of infiltration, the boiling point and viscosity of liquid fuel and the effective thermal conductivity of sand bed are also important influencing factors. [ABSTRACT FROM AUTHOR]

The article focuses on explosion and fire hazards at production facilities of enterprises where flammable liquids and gases, categorized by explosion and fire risks, are processed, handled, transported, and stored. The goal to be attained and the tasks to be solved towards this end are formulated in the article. Consolidated areas of knowledge, accumulating results of research into risk assessment within systems of integrated safety implemented at production facilities, are considered by the author. A model for development of a novel set of research and methodological instruments (methods, techniques, software and hardware) is presented for its further practical application. The problem of developing integrated safety systems for industrial facilities, posing explosion and fire hazards, as well as the solution, are presented by the author for the first time. The novelty of the solution lies in the computation of validity of the practical application of a novel set of research and methodological instruments. A reduction in damage from accidents and fires at production facilities is demonstrated. Ultimately, the socio-economic problem of reducing damage from accidents and fires is solved not only by Russian production facilities, but also by government agencies, including the EMERCOM of Russia (Ministry of the Russian Federation for Civil Defense, Emergencies and Elimination of Consequences of Natural Disasters), Ministry of Labor and Social Protection of Russia, and Federal Environmental, Industrial and Nuclear Supervision Service of Russia. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accidental spillage of flammable liquids on in-service ships and offshore installations may lead to pool fires, which are likely to spread over a particularly large area in large compartments under ship motion, resulting in extensive damage. However, the effect of the spreading extent of liquid fuel due to inclined ship motion on pool fire consequences has not been considered in the existing literature. Thus, in this study, fuel discharge experiments were conducted to investigate the spreading behaviour under different substrate inclination angles and discharge rates. The experimental results were analysed to derive closed-form expressions to predict the spreading extent of liquid fuel in large compartments. Additionally, the effects of surface inclination on fire consequences were investigated using the Fire Dynamics Simulator in terms of the heat release rate. The findings can provide guidance for effective fire safety design and establishing a realistic fire modelling methodology for ships and offshore installations. [ABSTRACT FROM AUTHOR]

Earthquakes have great damage potential and importance in risk management and structural engineering, causing fires in buildings such as residences and commercial spaces. Post-earthquake fires (PEF) are secondary disasters that can cause material and moral destruction and loss of life. Similar to natural disasters, they show the time of occurrence and possible scenarios in places. This study aims to analyse and examine what precautions can be taken to prevent or minimize PEF through risk assessment. In this study, a literature review was conducted with the tracking method, focusing on examples from the world where the fires that occur as a secondary effect of the earthquake can cause devastating damages and significant disasters, and inferences are made by classifying the data obtained. Many factors, such as gas leaks due to earthquakes, cracks in pipelines, and short circuits in electrical installations, can cause fires. In addition, flammable liquid or combustible gas emissions and fire protection disturbances create significant fire hazards after earthquakes. In this paper, in which the causes and consequences of fires are analysed, risks, the evaluation process depending on the risks, the precautions that can be taken according to the situations that the risks will cause, and the models developed are emphasized. The research is a reference study with the expectation that there will be an increase in the number of studies examining experimental and physical PEF models. [ABSTRACT FROM AUTHOR]

Current Li battery technology employs graphite anode and flammable organic liquid electrolytes. Thus, the current Li battery is always facing the problems of low energy density and safety. Additionally, the sustainable supply of Li due to the scarce abundance of Li sources is another problem. An all-solid-state Mg battery is expected to solve the problems owing to non-flammable solid-state electrolytes, high capacity/safety of divalent Mg metal anode and high abundance of Mg sources; therefore, solid-state electrolytes and all-solid-state Mg batteries have been researched intensively last two decades. However, the realization of all-solid-state Mg batteries is still far off. In this article, we review the recent research progress on all-solid-state Mg batteries so that researchers can pursue recent research trends of an all-solid-state Mg battery. At first, the solid-state electrolyte research is described briefly in the categories of inorganic, organic and inorganic/organic composite electrolytes. After that, the recent research progress of all-solid-state Mg batteries is summarized and analyzed. To help readers, we tabulate electrode materials, experimental conditions and performances of an all-solid-state Mg battery so that the readers can find the necessary information at a glance. In the last, challenges to realize the all-solid-state Mg batteries are visited. [ABSTRACT FROM AUTHOR]

The object of this study is a class B fire, which is extinguished with sprayed water. The subject of the study is the characteristics of class B fires when they are extinguished with sprayed water. Diffusion burning of a flammable liquid is considered as such a fire, and its extinguishing is carried out by cooling the flame. Heat and oxygen balance equations are used to build a mathematical model describing the fire extinguishing process. The components of the heat balance equation are the power of heat during heat release due to the chemical reaction of liquid combustion and the power of heat dissipated to the environment. The second component takes into account heat removal due to radiation, convection, and evaporation. The component of removed heat due to evaporation takes into account the Sreznevsky constant. The mathematical model that describes the process of extinguishing a class B fire is built in the class of models belonging to differential equations with constant coefficients. Analytical expressions were obtained for these static and dynamic coefficients, which include thermophysical, kinematic, and geometric parameters of the flame and fire extinguishing agent. To determine these characteristics, the constructed mathematical fire model was transformed using the integral Laplace transform. The dynamic characteristics of the fire were obtained in the time domain – the transient function of the fire, and in the frequency domain – the amplitude-frequency and phase-frequency characteristics of the fire. It is shown that the parameters of these dynamic characteristics should be determined experimentally. Experimental methods for determining parameters of dynamic fire characteristics have been devised. The presence of dynamic characteristics of class B fire makes it possible to spread the proven methods of the theory of control systems to design effective fire extinguishing systems [ABSTRACT FROM AUTHOR]

Solid‐state batteries (SSBs) have received significant attention due to their high energy density, reversible cycle life, and safe operations relative to commercial Li‐ion batteries using flammable liquid electrolytes. This review presents the fundamentals, structures, thermodynamics, chemistries, and electrochemical kinetics of desirable solid electrolyte interphase (SEI) required to meet the practical requirements of reversible anodes. Theoretical and experimental insights for metal nucleation, deposition, and stripping for the reversible cycling of metal anodes are provided. Ion transport mechanisms and state‐of‐the‐art solid‐state electrolytes (SEs) are discussed for realizing high‐performance cells. The interface challenges and strategies are also concerned with the integration of SEs, anodes, and cathodes for large‐scale SSBs in terms of physical/chemical contacts, space‐charge layer, interdiffusion, lattice‐mismatch, dendritic growth, chemical reactivity of SEI, current collectors, and thermal instability. The recent innovations for anode interface chemistries developed by SEs are highlighted with monovalent (lithium (Li+), sodium (Na+), potassium (K+)) and multivalent (magnesium (Mg2+), zinc (Zn2+), aluminum (Al3+), calcium (Ca2+)) cation carriers (i.e., lithium‐metal, lithium‐sulfur, sodium‐metal, potassium‐ion, magnesium‐ion, zinc‐metal, aluminum‐ion, and calcium‐ion batteries) compared to those of liquid counterparts. [ABSTRACT FROM AUTHOR]

Fluorosurfactants are the key ingredients in the formulations of aqueous film-forming foams (AFFFs) for extinguishing flammable liquids, thus developing high-efficient and low-toxic fluorosurfactants is desirable in AFFFs application. Herein, a series of hyperbranched polymeric fluorosurfactants (HPFs) were successfully synthesized through sequentially modifying hyperbranched polyethylenimine (PEI) with the hydrophilic poly(ethylene glycol) (PEG) chains and the hydrophobic C6/C4-based perfluoroalkyl chains, which were verified by FTIR, 1H- and 19F-NMR. The surface tensions of all the HPFs in water were measured, and the corresponding physicochemical parameters were interpreted. It was found that the surface activities of HPFs could be tuned through adjusting the ratio of PEG to perfluoroalkyl chains, the length of perfluoroalkyl chains, the molecular weight of PEI core, but not the PEG chain length. In the binary mixture of HPFs with the commercial small molecule fluorosurfactant Capstone™ 1157 (C1157), a strong synergism led to the elevation of surface activity, which was attributed to the efficient encapsulation of C1157 guests by the compact hyperbranched HPFs as the hosts. The utilization of HPF/C1157 as fluorosurfactant ingredients in AFFF formulations could realize much higher fire-extinguishing efficiency towards flammable oils than the control AFFFs prepared from the polymeric Capstone™ 1460 or the neat C1157. [ABSTRACT FROM AUTHOR]

Safe and secure vehicle routing problems refer to the transportation of dangerous (e.g., flammable liquids) or valuable goods (e.g., cash), the surveillance of streets (e.g., police patrols) or other areas (e.g., those within a factory or building), and the response to sudden incidents (e.g., robberies or street disruptions). It thus covers a multitude of models and methods with each having its own objective and constraints, such as unpredictability or risk. We review and classify literature in this field and thereby identify a starting point for researchers in this evolving and practically relevant field. Our study reveals that there are 82 articles that cover aspects related to safe and secure routing, a majority of which were published in the last five years. We classify the articles into five main categories: (i) transportation of hazardous materials, (ii) patrol routing, (iii) cash‐in‐transit, (iv) dissimilar routing problems, and (v) modeling of multi‐graphs. Categories (i)–(iv) elaborate on the problem studied, while (v) provides a general concept based on road network characteristics most commonly found in safe and secure routing problems. Relevant methods and instances, along with their similarities and dissimilarities, have also been discussed in the paper. Furthermore, specific problem characteristics and future research directions are identified. [ABSTRACT FROM AUTHOR]

The object of this study is the process of liquid combustion in the pool, and the subject of the study is the characteristics of the random process that describes the heat flow by radiation. Such, in particular, are the law of distribution, mathematical expectation, and correlation function. An experimental study of the combustion of used motor oil in a pool measuring 9.5×8.7 m² was carried out. The mathematical expectation and variance of the cross-sectional area of the flame were determined by video recording followed by the analysis of individual frames. Testing of the hypothesis about the normal law of distribution of the cross-sectional area showed that with a confidence probability of 0.95, the proposed hypothesis does not contradict the experimental data. A selective correlation function and its approximation in the form of σ²exp(–α|τ|) were constructed. Due to the linear relationship between the cross-sectional area and the heat flux by radiation from the fire, the latter will also have a normal distribution law. At the same time, the magnitude of pulsations (the ratio of the rms deviation to the mathematical expectation) for these random processes will be the same. The value of the parameter α of the correlation function will also be the same. Taking into account the inertial properties of the device for measuring the heat flux density, a comparison of the experimentally measured values of the heat flux density with the calculated ones was carried out. The measurement results fall into the intervals corresponding to the confidence probability of 0.95. At the same time, the maximum deviation between calculated and experimental data is 14 %. From a practical point of view, the built stochastic model opens up possibilities for taking into account random flame pulsations when determining safe zones for the location of personnel and equipment. The model can be used to specify the thermal effect of fire on steel and concrete structures. [ABSTRACT FROM AUTHOR]

Gel‐polymer electrolytes (GPEs) offer a suitable alternative to flammable organic liquid electrolytes in lithium‐oxygen batteries (LOBs) to address safety concerns. However, a major challenge with GPEs is their low ionic conductivity. To enhance the ionic conductivity of GPEs, active inorganic particles have been incorporated. To increase the ionic conductivity of GPE, active inorganic particles have been reinforced in GPE. While this increases the ionic conductivity, it also leads to blockage of the cathode porous structure and reduces the actual surface area of the cathode materials, resulting in poor battery performance. This study proposes a novel double‐layer polymer gel electrolyte (d‐GPE) that exhibits both high ionic conductivity and stability for quasi solid‐state LOBs. The double‐layer GPE consists of a bare GPE layer integrated in the cathode, and a composite GPE (c‐GPE, containing 5 wt. % lithium aluminum titanium phosphate (LATP)), which is in contact with Li anode and bare‐GPE. The produced double‐layer gel polymer electrolyte displays high reaction kinetic and better stability due to the excellent electrode/electrolyte interface and rapid oxygen diffusion in the air‐cathode. Furthermore, the d‐GPE electrolyte is resistant to fire and protects Li from dendrite growth and water molecules attack, indicating tremendous promise for the development of practical LOBs. [ABSTRACT FROM AUTHOR]

As a representative renewable biofuel, ethanol can reduce mankind's dependence on petroleum resources and the emission of greenhouse gases and other pollutants. In recent years, the application of ethanol in the aviation field has begun to be a concern of scholars. As ethanol is a flammable liquid, it is significant to study its explosion characteristics in aviation conditions from a safety perspective. In this work, at 20 kPa, the explosion characteristics of ethanol–air mixtures (concentration 6~12%) were experimentally and numerically studied under an initial temperature range of 303 K~363 K. The effects of the initial temperature and concentration on the maximum explosion pressure, maximum rate of pressure rise, explosion time, and fast burning time were analyzed. In addition, the heat loss fraction and sensitivity analysis were examined and discussed. The main conclusions are as follows: A linear relationship exists between the maximum explosion pressure and the reciprocal of the initial temperature. The maximum rate of a pressure rise appears to decrease or at least approach a constant value as the initial temperature increases. The explosion time is significantly dependent on the concentration. At a constant concentration, the proportions of heat loss are approximately constant except for 12%. In our sensitivity analysis, R1 (H + O2 <=> O + OH) was the dominant elementary reaction. [ABSTRACT FROM AUTHOR]

In a fire environment, liquid storage tanks are prone to integral cracking and eventually boiling liquid expanding vapor explosion (BLEVE), which a fireball, generates overpressure and ejected fragments with great impact on the safety of the tank area. Hence, it is important to reveal the influencing factors of the liquid storage tank failure process and the conditions that trigger integral cracking failure for the flammable liquid tank explosion accident prevention. This paper is aimed at the failure problem of metal storage tanks exposed to high temperature for a long time, through the fire experiment of small liquid tanks, taking the filling rate of tanks itself and the fire engulfment area as variables, the failure mechanism of tanks fire environment was explored from the aspects of pressure response, temperature response, failure form and tank deformation characteristics. A criterion was proposed to determine whether BLEVE will occur, which is based on the comprehensive analysis of the influence of tank internal pressure and high temperature damage of the material. [ABSTRACT FROM AUTHOR]

The rising of diseases caused by multidrug‐resistant bacteria has encouraged researchers to explore more antimicrobial substances, as well as chemicals capable of potentiating the action of existing ones against multidrug‐resistant bacteria. Anacardium occidentale produces a fruit known as cashew nut, filled with a dark, almost black, caustic, and flammable liquid called cashew nutshell liquid (CNSL). The goal of the study was to evaluate the intrinsic antimicrobial activity of the major compounds present in CNSL, called anacardic acids (AA), as well as their possible modulatory action as an adjuvant of Norfloxacin against a Staphylococcus aureus strain overproducing the NorA efflux pump (SA1199B). Microdilution assays were performed to determine the minimum inhibitory concentration (MIC) of AA against different microbial species. Norfloxacin and Ethidium Bromide (EtBr) resistance modulation assays were performed in the presence or absence of AA against SA1199‐B. AA showed antimicrobial activity against Gram‐positive bacterial strains tested but no activity against Gram‐negative bacteria or yeast strains. At subinhibitory concentration, AA reduced the MIC values for Norfloxacin and EtBr against the SA1199‐B strain. Furthermore, AA increased the intracellular accumulation of EtBr in this NorA overproducer strain, indicating that AA are NorA inhibitors. Docking analysis showed that AA probably modulates Norfloxacin efflux by spatial impediment at the same binding site of NorA. [ABSTRACT FROM AUTHOR]

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Digital platforms, electric vehicles, and renewable energy grids all rely on energy storage systems, with lithium-ion batteries (LIBs) as the predominant technology. However, the current energy density of LIBs is insufficient to meet the long-term objectives of these applications, and traditional LIBs with flammable liquid electrolytes pose safety concerns. All-solid-state lithium–oxygen batteries (ASSLOBs) are emerging as a promising next-generation energy storage technology with potential energy densities up to ten times higher than those of current LIBs. ASSLOBs utilize non-flammable solid-state electrolytes (SSEs) and offer superior safety and mechanical stability. However, ASSLOBs face challenges, including high solid-state interface resistances and unstable lithium-metal anodes. In recent years, significant progress has been proceeded in developing new materials and interfaces that improve the performance and stability of ASSLOBs. This review provides a comprehensive overview of the recent advances and challenges in the ASSLOB technology, including the design principles and strategies for developing high-performance ASSLOBs and advances in SSEs, cathodes, anodes, and interface engineering. Overall, this review highlights valuable insights into the current state of the art and future directions for ASSLOB technology. [ABSTRACT FROM AUTHOR]

The fabrication of all electrolytes from noncombustible ceramic materials offers a superior option for providing safer and higher-capacity batteries to fulfill future energy needs. To achieve a competitive performance with combustible liquid electrolytes used in commercial Li-ion batteries, the creation of ceramic material compositions with a high electrical conductivity is necessary. Here, we report that co-doping with W and halogens results in a superconductivity of 13.78 mS cm−1 in a cubic-phase Na3SbS4 glass ceramic electrolyte. After undergoing high-temperature heat treatments, the W ions in the electrolyte can facilitate the replacement of S atoms with halogens, introducing many Na vacancies. The samples also had a high degree of cycling stability. An excellent glass ceramic electrolyte for Na ion batteries will be constructed for Na3SbW0.25Cl0.25S4. [ABSTRACT FROM AUTHOR]

An issue related to the use of foaming agents to extinguish fires involving flammable liquids is to ensure the efficiency of vapor insulation of flammable liquid and the foam stability during operation. Therefore, the object of research was a change in the insulating properties of the foaming agent film when interacting with a polar combustible substance. It has been proven that the presence of foaming agent on a flammable liquid leads to the formation of an insulating film on the surface resistant to the combustion temperature of the liquid, due to which re-ignition shifts towards longer time. A film of foaming agent was formed on the surface of the flammable liquid by leaking from the screen, which led to the insulation of the surface. The measured contact area of the foaming film with the electrode was more than 6.2·10-3 m2, which indicates the formation of a barrier for temperature, which collapses over time. According to experimental data on changes in electrical resistance, the critical contact area of the foaming film with the electrode was calculated, at which the film is destroyed. Based on the derived dependences, the change in the process of mass transfer of the foaming film to a flammable liquid was calculated, equal to about 800 s. The maximum possible mass transfer of the foaming agent into the flammable liquid and the reduction of insulation capacity were evaluated. The peculiarities of foam supply to the surface of alcohol through the screen are that the quenching time was about 156 s while the critical intensity of the supply of the working solution of the foaming agent was 0.054 dm3/(m2·s). And the time interval before re-ignition was about 470 s, which is enough to cool the fire site. Thus, there is reason to assert the possibility of targeted control over the processes of extinguishing polar flammable liquids with a foaming agent. [ABSTRACT FROM AUTHOR]

To carry out research on the particle size distribution, micro -morphology, and composition characteristics of combustible combustion smoke particles, and comprehensively understand the smoke information of fires. Methods The cable outer sheath, rubber tires, wire insulation layer, insulating cardboard, transformer oil, and fire residue oil at the combustion site of the substation fire were collected. Through combustion simulation experiments, use a particle matter classification sampler to collect the smoke particles released by combustion and analyze the particle size distribution characteristics of different smoke particles and their distribution in different deposition sites of the human respiratory tract. By comparing the scanning electron microscope images of different particle sizes of smoke dust, the micro-morphology and elemental composition of different particle sizes were surveyed. Results Based on ion chromatography analysis, Cl- emission factor was 0.089 2-1.207 2 滋g/g, accounting for 57.3%-67.9% of water-soluble ions, and there were differences in its particle size distribution characteristics between solid and liquid combustibles. Conclusions The smoke particles released by different combustibles were mainly particles with a diameter less than 0.25 滋m, and there were differences in Cl - emission factors. These differences could be used as the basis for evaluating the source of smoke dust and respiratory exposure assessment of personnel at fire scenes. [ABSTRACT FROM AUTHOR]

Solid-state batteries (SSBs) are promising next-generation batteries due to their potential for achieving high energy densities and improved safety compared to conventional lithium-ion batteries (LIBs) with a flammable liquid electrolyte. Despite their huge market potential, very few studies have investigated SSB recycling processes to recover and reuse critical raw metals for a circular economy. For conventional LIBs, hydrometallurgical recycling has been proven to be able to produce high-quality products, with leaching being the first unit operation. Therefore, it is essential to establish a fundamental understanding of the leaching behavior of solid electrolytes as the key component of SSBs with different lixiviants. This work investigates the leaching of the most promising Al- and Ta-substituted Li7La3Zr2O12 (LLZO) solid electrolytes in mineral acids (H2SO4 and HCl), organic acids (formic, acetic, oxalic, and citric acid), and water. The leaching experiments were conducted using actual LLZO production waste in 1 M of acid at 1:20 S/L ratio at 25 °C for 24 h. The results showed that strong acids, such as H2SO4, almost completely dissolved LLZO. Encouraging selective leaching properties were observed with oxalic acid and water. This fundamental knowledge of LLZO leaching behavior will provide the basis for future optimization studies to develop innovative hydrometallurgical SSB recycling processes. [ABSTRACT FROM AUTHOR]