Fire Safety Journal最新文献_第6页

Experimental investigation of cellular steel beams at ambient and elevated temperatures 室温和高温条件下蜂窝钢梁的试验研究

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-11-03 DOI: 10.1016/j.firesaf.2025.104574

Luana V. da Silva , Nickolas Giacomitti , Débora Ferreira , Nuno Lopes , Luís M.R. Mesquita

Cellular steel beams, commonly used in modern construction, exhibit complex failure mechanisms that have not been thoroughly explored, especially under fire conditions. This research investigates the structural behaviour of cellular beams under both ambient and elevated temperatures, with a focus on load-bearing capacity and failure modes. Experimental tests were conducted on a solid beam and six cellular beams with varying hole spacings and diameters at different temperatures. All beams were tested under three-point bending, subjecting the openings and the web posts to different combinations of bending moments and shear forces. Experimental maximum loads and failure modes are compared with the design method of EN1993-1-13 and EN1993-1-2. At ambient temperature, failure modes varied with beam design: specimens with smaller opening spacings failed by web-post buckling, while larger openings resulted in a Vierendeel mechanism. While the Eurocode predictions for load capacity were conservative under ambient conditions, the design model did not accurately predict the correct failure mode. Elevated temperatures significantly reduced the load capacity and, in some cases, changed the collapse mechanism. These results highlight that current design rules are unreliable in predicting the failure mode and may not ensure safety at higher temperatures, stressing the need for specific design rules for cellular beams in fire conditions.

在现代建筑中广泛使用的蜂窝钢梁，其复杂的破坏机制尚未得到充分的研究，特别是在火灾条件下。本研究调查了蜂窝梁在环境和高温下的结构行为，重点关注承重能力和破坏模式。在不同温度下，对一根实心梁和6根孔间距和直径不同的蜂窝梁进行了实验测试。所有梁都在三点弯曲下进行了测试，使开口和腹板柱受到不同的弯矩和剪力组合。将试验最大载荷和破坏模式与EN1993-1-13和EN1993-1-2的设计方法进行了比较。在环境温度下，梁的破坏模式因梁的设计而异：开口较小的试件因网柱屈曲而破坏，而开口较大的试件则因Vierendeel机制而破坏。虽然欧洲规范对环境条件下负荷能力的预测是保守的，但设计模型不能准确预测正确的失效模式。高温显著降低了承载能力，在某些情况下，还改变了坍塌机制。这些结果强调，目前的设计规则在预测失效模式方面是不可靠的，并且可能无法确保高温下的安全，强调需要针对火灾条件下的蜂窝梁制定特定的设计规则。

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引用次数: 0

Experimental investigation on mechanical properties of cast steel at elevated temperatures 铸钢高温力学性能的试验研究

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-11-01 DOI: 10.1016/j.firesaf.2025.104571

Hongbo Liu , Bingxu Han , Liulu Guo , Zhihua Chen

Cast steel is extensively used in diverse building structures, especially for complex joints and members. To guarantee the safety of cast steel components during fire events, precise characterization of mechanical properties and constitutive behavior of cast steel at elevated temperatures is imperative. This study presents a comprehensive experimental investigation of G20Mn5N and G20Mn5QT cast steels. Key mechanical property indexes of cast steel at elevated temperatures were determined and compared to code-specified values and high-temperature data for conventional structural steels. Results indicate that the cast steels exhibited a blue brittleness phenomenon at 300 °C, characterized by increased ultimate strength and reduced toughness and ductility, ultimately predisposing them to brittle failure. Cast steel exhibited pronounced thermochromic behavior and ductile damage characteristics at elevated temperatures. With increasing temperature, the modulus of elasticity, yield strength, and ultimate strength of cast steel decreased, while elongation initially diminished before increasing. G20Mn5QT demonstrated superior fire resistance compared to G20Mn5N. Highly accurate empirical prediction equations for critical mechanical properties and theoretical stress-strain formulas at elevated temperatures were developed.

铸钢广泛应用于各种建筑结构，特别是复杂的接缝和构件。为了保证铸钢构件在火灾中的安全，精确表征铸钢在高温下的力学性能和本构行为是必不可少的。本文对G20Mn5N和G20Mn5QT铸钢进行了综合试验研究。测定了铸钢在高温下的关键力学性能指标，并与规范规定的数值和常规结构钢的高温数据进行了比较。结果表明，铸钢在300℃时表现出蓝色脆性现象，其特征是极限强度增加，韧性和延展性降低，最终导致脆性破坏。铸钢在高温下表现出明显的热致变色行为和延展性损伤特征。随着温度的升高，铸钢的弹性模量、屈服强度和极限强度下降，伸长率先降低后升高。与G20Mn5N相比，G20Mn5QT表现出更好的耐火性。建立了高精度的临界力学性能经验预测方程和高温下的应力-应变理论公式。

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引用次数: 0

Cooling methods impact on post-fire residual bond properties of bimetallic steel bars in seawater concrete 冷却方式对海水混凝土中双金属钢筋火灾后残余粘结性能的影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-30 DOI: 10.1016/j.firesaf.2025.104569

Xuanyi Xue , Fei Wang , Jianmin Hua , Neng Wang , Shuang Yan

The bimetallic steel bar (BSB) is a new type of corrosion-resistant steel bar composed of stainless steel cladding and carbon steel substrate. In ocean engineering, the combination of BSB and seawater concrete can better utilize in-situ resources, and reduce the cost of seawater desalination and material transportation. To evaluate the residual bearing performance of the bimetallic steel bar-seawater concrete (BSBSC) structure post-fire, it is essential to elucidate the bond behavior of BSBSC exposed to elevated temperatures. In this study, the effects of high temperatures and cooling methods on the bond performance of BSBSC were investigated. The results indicated that the elevated temperature significantly weakened the bonding strength of BSBSC. The bonding strength of BSBSC exposed to 400 °C had decreased by a maximum of 63.54 %. As the temperature increased, the difference in bonding strength between air cooling and water cooling decreased from 27.61 % to 3.60 %. The peak-load slip initially declined and subsequently rose as the temperature increased with the transition temperature between 200 °C and 400 °C. A predictive bond stress-slip constitutive model for BSBSC was formulated. The design method for steel bar anchorage length in current design standards has been revised to take into account the fire risk.

双金属棒材（BSB）是一种由不锈钢包层和碳钢基体组成的新型耐腐蚀棒材。在海洋工程中，BSB与海水混凝土的结合可以更好地利用就地资源，降低海水淡化和材料运输的成本。为了评价双金属钢筋-海水混凝土（BSBSC）结构火灾后的残余承载性能，有必要研究高温下BSBSC的粘结行为。在本研究中，研究了高温和冷却方式对BSBSC粘结性能的影响。结果表明，温度升高显著降低了BSBSC的结合强度。BSBSC在400℃下的结合强度最大下降了63.54%。随着温度的升高，风冷与水冷的结合强度差由27.61%减小到3.60%。在200℃~ 400℃之间，随着温度的升高，峰载滑移量呈先下降后上升的趋势。建立了BSBSC的预测粘结应力-滑移本构模型。对现行设计标准中钢筋锚固长度的设计方法进行了修订，以考虑火灾风险。

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引用次数: 0

Surrogate based uncertainty quantification in pyrolysis modeling: A comparative analysis 热解建模中基于代理的不确定性量化：比较分析

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-28 DOI: 10.1016/j.firesaf.2025.104570

Hamza Jamil, Fabian Brännström

In this work we analyze and compare the uncertainty propagation in a comprehensive pyrolysis model that captures an experimental setup using different approaches: namely polynomial chaos expansion (PCE), proper orthogonal decomposition with interpolation (PODI), Gaussian process regression (GPR) and quasi-Monte Carlo simulations. We start with inverse modeling to obtain the nominal parameter values for a set of kinetic and thermal parameters that devise the essential equations of the model. This is followed by a global sensitivity analysis to choose the most critical parameters for which the stochastic uncertainty is studied in the output over time. For the uncertainty, we observe the convergence behavior for mean, standard deviation, skewness and kurtosis. The statistical moments convergence analysis shows PCE to exhibit comparatively poor convergence behavior for standard deviation, and divergence for skewness and kurtosis. On the other hand, the computational effort required for GPR does not scale well in terms of accuracy with increased number of samples. Whereas, PODI is observed to converge faster while being comparatively less computationally intensive than other surrogate approaches. In conclusion, PODI poses as the most prominent approach among the aforementioned for uncertainty quantification in highly resolved pyrolysis and flame spread models.

在这项工作中，我们分析和比较了一个综合热解模型中的不确定性传播，该模型采用了不同的方法，即多项式混沌展开（PCE）、适当的正交插值分解（PODI）、高斯过程回归（GPR）和准蒙特卡罗模拟。我们从逆建模开始，获得一组动力学和热参数的标称参数值，从而设计出模型的基本方程。其次是全局敏感性分析，以选择最关键的参数，研究随时间输出的随机不确定性。对于不确定性，我们观察到均值、标准差、偏度和峰度的收敛性。统计矩收敛分析表明，PCE对标准差表现出较差的收敛性，对偏度和峰度表现出发散性。另一方面，GPR所需的计算工作量随着样本数量的增加而不能很好地扩展精度。然而，与其他代理方法相比，PODI的收敛速度更快，而计算强度相对较低。综上所述，PODI是上述方法中对高分辨热解和火焰蔓延模型的不确定性量化最突出的方法。

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引用次数: 0

Various methods of flame extinguishing by CO2 hydrate 用二氧化碳水合物灭火的各种方法

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-27 DOI: 10.1016/j.firesaf.2025.104567

S.Y. Misyura , V.S. Morozov , P.A. Strizhak

Extinguishing the flame of wooden samples by various means: CO₂ hydrate tablet, CO₂ hydrate powder, sand, NH₄H₂PO₄, water spray, foam spray (water and SDS) was studied experimentally and theoretically. The experiments were performed both outdoors and in a closed chamber. The tablet and the CO₂ hydrate powder have shown the minimum sample weight for complete quenching. The novelty of the research lies in the use of shells with tablets to extinguish a fire in a closed room (chamber). Previous studies were carried out with the CO₂ hydrate powder. The presented work shows the advantages of using CO₂ hydrate tablets. Experiments were performed for different sample masses and in a wide range of closed chamber volumes. After the projectile throw into the chamber, three characteristic modes are realized: heating and dissociation of tablets, rupture of the shell and instantaneous release of CO₂, and longer dissociation of CO₂ hydrate tablet. It is shown that extinguishing in the open air is realized mainly due to the heat of phase transitions. In a closed room, the predominant extinguishing effect is associated with very rapid release of CO₂ gas and rapid suppression of oxygen and oxidation reactions. The dissociation of a gas hydrate tablet, the tablet heating time until the shell break, and the maximum dissociation time of the tablet are simulated. A technique of multi-cycle quenching with a delay in the time of rupture of several shells is proposed.

实验和理论研究了不同灭火方法：CO2水合片、CO2水合粉、沙子、NH4H2PO4、水喷雾、泡沫喷雾（水和SDS）。实验在室外和封闭的室内进行。片剂和CO2水合物粉末显示了完全淬火所需的最小样品重量。这项研究的新颖之处在于使用带有药片的贝壳来扑灭封闭房间（密室）中的火。以前的研究都是用二氧化碳水合物粉末进行的。本文的工作显示了使用二氧化碳水合物片的优点。实验进行了不同的样品质量和广泛的封闭腔体积范围。抛丸入腔后，实现三种特征模式：片剂加热解离、壳体破裂瞬间释放CO2、CO2水合物片剂长时间解离。结果表明，在露天环境中灭火主要是通过相变热来实现的。在一个封闭的房间里，主要的灭火效果与CO2气体的快速释放和氧气和氧化反应的快速抑制有关。模拟了一种气体水合物片剂的解离过程、片剂加热至破壳时间以及片剂的最大解离时间。提出了一种延迟多壳断裂时间的多循环淬火技术。

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引用次数: 0

Critical ignition limits and thermal behaviors of asphalt combustion under varied radiation conditions: Experimental exploration and 2-D Smouldering Kinetics Interpretation 不同辐射条件下沥青燃烧的临界点火极限和热行为：实验探索和二维阴燃动力学解释

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-23 DOI: 10.1016/j.firesaf.2025.104564

Kai Zhu , Dan Zhao , Han Yuan , Qiang Wang , Linghan Zhou , Ke Wu , Zhirong Liang

Asphalt, a carbon-rich and chemically complex material, exhibits intricate combustion behavior under fire conditions. Despite its widespread use in over 90 % of pavements in the United States and China, its ignition dynamics under varying radiative conditions remain poorly understood. This research explored the thermal behaviors of combustible asphalt under various radiation intensities (0–50 kW/m²) and durations (0–60 min) experimentally, with smouldering reaction kinetics interpreted numerically. It is observed that under sufficient radiation duration (60 min), 5 kW/m² is the critical limit of radiation intensity; while under high radiation intensity (50 kW/m²), nearly 1 min is the critical limit of radiation duration. 2-D Smouldering Kinetics Interpretation revealed that critical radiation intensity determines the overcoming of activation energy, and critical radiation duration determines the potential of thermal-storage capacity for ignition to trigger smouldering combustion. Moreover, the reaction kinetics reflected the transition from pyrolysis-dominated to pyrolysis/oxidation-coupled reactions, significantly varying the asphalt/char/ash proportions. The findings establish critical thresholds for asphalt smoldering ignition, which are characterized by dual logarithm correlation between the radiation intensity and ignition time. This is complemented by fundamental analysis of species evolution dynamics and chemical energy distribution, providing insights valuable to fire safety science.

沥青是一种富含碳且化学性质复杂的材料，在火灾条件下表现出复杂的燃烧行为。尽管它在美国和中国90%以上的路面上广泛使用，但其在不同辐射条件下的点火动力学仍然知之甚少。本研究通过实验研究了不同辐射强度（0-50 kW/m2）和持续时间（0-60 min）下可燃沥青的热行为，并对阴燃反应动力学进行了数值解释。在足够的辐射持续时间（60min）下，5kw /m2是辐射强度的临界极限；而在高辐射强度（50 kW/m2）下，近1 min是辐射持续时间的临界极限。二维阴燃动力学解释表明，临界辐射强度决定了活化能的克服，临界辐射持续时间决定了点火蓄热能力触发阴燃的潜力。反应动力学反映了从热解为主反应到热解/氧化耦合反应的转变，沥青/炭/灰分比例发生了显著变化。研究结果建立了沥青阴燃的临界阈值，该阈值与辐射强度和着火时间呈双对数相关关系。这是对物种进化动力学和化学能分布的基本分析的补充，为消防安全科学提供了有价值的见解。

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引用次数: 0

Radiation effects on horizontal flame spread under non-steady airflows 非定常气流下辐射对火焰水平传播的影响

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-23 DOI: 10.1016/j.firesaf.2025.104565

Pablo E. Pinto , Xiuqi Xi , Maria Thomsen , James L. Urban

Thermal radiation from the flame to the unburned fuel plays a key role in horizontal concurrent flame spread by heating the fuel surface and influencing the spread of the flame. This work investigates thermal radiation in horizontal concurrent flame spread under non-steady forced airflow conditions. Experiments are conducted using black cast polymethyl methacrylate (PMMA) sheets with a thickness of 1 mm as fuel. A non-steady airflow with a sinusoidal profile is applied in each experiment, with a baseline of 300 mm/s, amplitudes of 100 and 200 mm/s, and frequencies of 1/32, 1/16, and 1/8 Hz. Radiation emitted by the flame is partially captured through heat flux gauge measurements and interpreted using geometrical data extracted from video footage. View factors between the flame and target surfaces (heat flux gauge and unburned sample) are calculated using a contour integral technique, with contours derived from parametric representations of the flame geometry based on flame height, burnout front, pyrolysis front, and flame tip position. This allows estimation of radiative heat transfer to the heated zone. Results show that the magnitude of flame radiation to the sample does not change significantly under non-steady airflow; however, the size of the heated zone exhibits a strong transient response. This response is attributed to the transient variation in flame extension length over the unburned surface. Additionally, two-dimensional spatial distributions of incident radiative heat flux to the heated zone are calculated and analyzed. The average flame spread rate is estimated by integrating the incident radiative heat flux, neglecting the convective contribution, which resulted in an underestimation of 18%–36% compared with the experimental flame spread rate.

火焰对未燃烧燃料的热辐射通过加热燃料表面，影响火焰的传播，在火焰水平同步传播中起着关键作用。本文研究了非定常强迫气流条件下火焰水平同步传播过程中的热辐射。实验采用厚度为1mm的黑色铸造聚甲基丙烯酸甲酯（PMMA）片材作为燃料。每次实验均采用非稳态正弦气流，基线为300 mm/s，振幅为100和200 mm/s，频率为1/32、1/16和1/8 Hz。火焰发出的辐射通过热通量计测量部分捕获，并使用从视频片段中提取的几何数据进行解释。火焰和目标表面（热通量计和未燃烧样品）之间的视图因子使用轮廓积分技术计算，轮廓源自基于火焰高度、燃尽前沿、热解前沿和火焰尖端位置的火焰几何参数表示。这样就可以估计向受热区传递的辐射热量。结果表明：在非稳态气流下，火焰对试样的辐射强度变化不大；然而，加热区的大小表现出强烈的瞬态响应。这种响应归因于火焰在未燃烧表面上延伸长度的瞬态变化。此外，还计算和分析了加热区的入射辐射热流密度的二维空间分布。平均火焰蔓延率是通过对入射辐射热流的积分来估算的，忽略了对流的贡献，与实验火焰蔓延率相比，低估了18%-36%。

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引用次数: 0

Performance based classifcation of product fire hazard 基于性能的产品火灾危险分类

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-22 DOI: 10.1016/j.firesaf.2025.104563

Richard E. Lyon, Tina Emami, Richard N. Walters, Timothy Salter

A dimensionless parameter Π measured in one or more cone calorimeter experiments successfully describes the level of fire safety of combustible products used in buildings, construction and passenger aircraft cabins as measured in regulatory tests. The product fire hazard Π is a compound reaction-to-fire property that correlates full-scale fire test results (ISO 9705, ASTM E84, 14 CFR 25) and product fire safety levels across international classifications.

在一个或多个锥形量热计实验中测量的无量纲参数Π成功地描述了在监管测试中测量的用于建筑物、建筑和客机客舱的可燃产品的消防安全水平。产品火灾危险Π是一种对火灾的复合反应特性，它与全尺寸火灾测试结果（ISO 9705, ASTM E84, 14 CFR 25）和国际分类的产品防火安全水平相关。

引用次数: 0

EvacUnet: A deep learning-based crowd density prediction method for assisting evacuation analysis EvacUnet：一种基于深度学习的人群密度预测方法，用于辅助疏散分析

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-17 DOI: 10.1016/j.firesaf.2025.104559

Mingyu Du, Ruolong Yi, Jun Zhang, Weiguo Song

Evacuation safety is an important research topic in the field of safety science. In this paper, we propose a deep learning-based method, EvacUnet, which, after inputting architectural floor plans, enables rapid calculation of density maps for different time points of interest. This method enables the rapid acquisition of density distributions during pedestrian evacuation processes across various scenes, thereby assisting in personnel management and contributing to the safe evacuation of individuals. To facilitate deep learning training, we introduce a large-scale evacuation dataset containing different types of buildings. Our test results demonstrate that EvacUnet is effective in generating density maps for various building structures and occupancy scenes. Importantly, in various scenes with differing levels of complexity, a consistently stable running speed is maintained. In engineering applications, this method will greatly save the costs of risk analysis for complex buildings, especially when multiple building structures and occupancy distributions need to be considered.

疏散安全是安全科学领域的一个重要研究课题。在本文中，我们提出了一种基于深度学习的方法，即EvacUnet，该方法在输入建筑平面图后，可以快速计算不同时间点的密度图。该方法能够在不同场景的行人疏散过程中快速获取密度分布，从而协助人员管理并有助于个人的安全疏散。为了便于深度学习训练，我们引入了一个包含不同类型建筑物的大规模疏散数据集。我们的测试结果表明，EvacUnet在为各种建筑结构和占用场景生成密度地图方面是有效的。重要的是，在各种复杂程度不同的场景中，始终保持稳定的运行速度。在工程应用中，该方法将大大节省复杂建筑的风险分析成本，特别是在需要考虑多个建筑结构和占用分布的情况下。

引用次数: 0

Acute lung injury in mice induced by halogenated olefins fire extinguishing agents: Role of chemical structure and gender differences 卤代烯烃灭火剂致小鼠急性肺损伤：化学结构和性别差异的作用

IF 3.3 3区工程技术 Q2 ENGINEERING, CIVIL

Fire Safety Journal

Pub Date : 2025-10-17 DOI: 10.1016/j.firesaf.2025.104562

Fuyao Yao , Kaitao Wang , Jingwen Bai , Xiaoyang Yu , Ruowen Zong

Halogenated olefin fire extinguishing agents, which are gaseous fire extinguishers, have been widely applied in fire protection due to their excellent fire suppression performance. However, current research has predominantly focused on their extinguishing efficiency, with limited attention given to their safety profiles or acute toxicity. This study conducted acute toxicity experiments in mice for four halogenated olefins fire extinguishing agents: 2-Bromo-3,3,3-trifluoropropene (2-BTP), 2-Chloro-3,3,3-trifluoropropene (xf), 2,3,3,3-tetrafluoropropene (yf), and cis-1,1,1,4,4,4-Hexafluoro-2-butene (mzz(Z)). Histopathological analysis of lung tissue and behavioral assessments revealed that all three types of halogenated olefins induced lung injury and respiratory distress in mice, but the severity of damage varied. 2-BTP and xf demonstrated higher acute toxicity, whereas yf and mzz(Z) exhibited relatively lower toxicity. Furthermore, all three classes of compounds were found to suppress body weight gain in mice, with 2-BTP having the most pronounced impact and yf and mzz(Z) showing milder effects. Although fluoro-bromo olefins like 2-BTP show superior fire suppression performance, they also present greater safety risks among halogenated olefins. Conversely, hydrofluoro olefins, despite their lower extinguishing efficiency, demonstrated a more favorable safety profile. This study provides new insights and guidance for the future development of fire extinguishing agents with low toxicity.

卤代烯烃灭火剂是一种气态灭火剂，由于其优异的灭火性能，在消防中得到了广泛的应用。然而，目前的研究主要集中在它们的灭火效率上，对它们的安全性和急性毒性的关注有限。本研究对四种卤代烯烃灭火剂进行了小鼠急性毒性实验：2-溴-3,3,3-三氟丙烯（2- btp）、2-氯-3,3,3-三氟丙烯（xf）、2,3,3,3-四氟丙烯（yf）和顺式-1,1,1,4,4,4-六氟-2-丁烯（mzz(Z)）。肺组织病理学分析和行为评估显示，三种类型的卤代烯烃均可引起小鼠肺损伤和呼吸窘迫，但损伤的严重程度不同。2-BTP和xf具有较高的急性毒性，而yf和mzz(Z)具有相对较低的毒性。此外，这三种化合物都被发现能抑制小鼠的体重增加，其中2-BTP的影响最明显，yf和mzz(Z)的效果较温和。2-BTP等氟溴烯烃虽然灭火性能优越，但在卤代烯烃中存在较大的安全隐患。相反，氢氟烯烃尽管灭火效率较低，但表现出更有利的安全性。本研究为今后低毒灭火剂的开发提供了新的见解和指导。

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引用次数: 0