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1.
通过系统梳理、比较大量古籍文献来探究“玫瑰”
词源,结论归结如下:1)“玫瑰”较早在汉代为“火齐(音
霁)珠”的宝珠,后晋代《西京杂记》中首次出现了作植物义
的西汉“玫瑰”,但其与现代植物学中玫瑰(Rosa rugosa)
的关联性尚缺乏直接证据;2)“玫瑰”含义的转变体现了珠
宝与同名植物在形、色、香上的关联;3)古代“玫瑰”二字
音形多重,早在汉代就记有与现代相同的读法,早期“玫”
又作“玟”,“瑰”还可音“回”;4)玫瑰作为植物别名众
多,如徘徊花、离娘草、玉蕊等,其中一些还与蔷薇属其他植
物有关联,且寓意多元。对古代“玫瑰”含义的考证研究,有
利于中国传统植物资源和文化的保护和传承,也为我国花文化
的创新与发展提供重要参考。 相似文献
2.
近年氢能已迅速成为能源领域“新宠”,正在迎来快速发展的战略机遇期,但氢安全问题仍然是制约其发展的关键,尤以高压氢气储运设施泄漏后引发喷射火灾害较为突出。为了探究高压氢气泄漏过程并对其引发喷射火灾特性参数变化进行评估,本文采用理论分析和实例验证相结合的方法对两起高压氢气泄漏实验案例(90 MPa氢气瓶和6 MPa氢气管道)进行了研究。结果表明:通过模型精度检验,Abel-Nobel气体状态方程适用于当前常用的多种高压氢气储运设施泄漏过程的描述。基于Abel-Nobel气体状态方程、火焰尺寸模型、辐射分数模型和热辐射模型构建的高压氢气泄漏喷射火过程预测模型对实验案例中的泄漏出口气体质量流量、氢喷射火焰长度和辐射热场等的模拟计算结果与实验测量数据基本一致,验证了模型有效性及所含假设合理性。另外在计算中还需要结合实际情况充分考虑高压氢气储运设施发生泄漏时产生的能量损失以及等温流动过程,从而对模型预测精度进行修正。上述结论对于工程实际、氢能安全利用以及灾害预防等具有重要现实意义。 相似文献
3.
William M. Pitts Martin Werrel Marco Fernandez Mary A. Long Evan A. Eisenberg James Filliben Cory D. Runyon 《火与材料》2021,45(1):127-154
Fire spread and growth on real‐scale four cushion mock‐ups of residential upholstered furniture (RUF) were investigated with the goal of identifying whether changes in five classes of materials (barrier, flexible polyurethane foam, polyester fiber wrap, upholstery fabric, and sewing thread), referred to as factors, resulted in statistically significant changes in burning behavior. A fractional factorial experimental design plus practical considerations yielded a test matrix with 20 material combinations. Experiments were repeated a minimum of two times. Measurements included fire spread rates derived from video recordings and heat release rates (HRRs). A total of 13 experimental parameters (3 based on the videos and 10 on the HRR results), referred to as responses, characterized the measurements. Statistical analyses based on Main Effects Plots (main effects) and Block Plots (main effects and factor interactions) were used. The results showed that three of the factors resulted in statistically significant effects on varying numbers of the 13 responses. The Barrier and Fabric factors had the strongest main effects with roughly comparable magnitudes. Foam was statistically significant for fewer of the responses and its overall strength was weaker than for Barrier and Fabric. No statistically significant main effects were identified for Wrap or Thread. Multiple two‐term interactions between factors were identified as being statistically significant. The Barrier*Fabric interaction resulted in the highest number of and strongest statistically significant effects. The existence of two‐term interactions means that it will be necessary to consider their effects in approaches designed to predict the burning behavior of RUF. 相似文献
4.
Sami Ullah Faiz Ahmad Abdullah G. Al-Sehemi Mohammed Ali Assiri Muhammad Rafi Raza Ahmad Irfan 《应用聚合物科学杂志》2021,138(17):50310
This research aims to study the effect of ammonium polyphosphate and expandable graphite on the intumescent coating formulations (ICF). The coating presented in this research article is based on carbon source expandable graphite (EG), blowing agent melamine, acid source ammonium polyphosphate (APP), epoxy resin as a binder with polyamide amine. The stability of the developed coating was verified at 950°C for 1-hour fire test. The results showed that the coating is stable and well bond with the steel substrate. The char was characterized by using FESEM, XRD, FTIR, DTA, TGA, XPS, Py-GCMS and Weathering Test. The morphology of the char was studied by SEM of the coating after furnace fire test. XRD and FTIR show the presence of graphite, borophosphate; boron oxide and sassolite in the residual char. TGA and DTG disclosed that EG improved the residual mass of coating. XPS analysis showed the char residue of IF5-APP-EG contains carbon and oxygen contents 47.50 and 40.70, respectively. Py-GCMS analysis described that the IF5-APP-EG released less gaseous compounds. The weathering test illustrated that's the char expansion of coatings samples was decreased due to the presence of a humid environment and UV light. The IF5-APP-EG showed the maximum char expansion, lower substrate temperature and high residual weight among the studied formulations. 相似文献
5.
Karolina Storesund Francine Amon Anne Steen‐Hansen Shayesteh Haghighatpanah Ida Larsson 《火与材料》2021,45(1):181-190
The aim of this exploratory study has been to investigate the fire properties and environmental aspects of different upholstery material combinations, mainly for domestic applications. An analysis of the sustainability and circularity of selected textiles, along with lifecycle assessment, is used to qualitatively evaluate materials from an environmental perspective. The cone calorimeter was the primary tool used to screen 20 different material combinations from a fire performance perspective. It was found that textile covers of conventional fibres such as wool, cotton and polyester, can be improved by blending them with fire resistant speciality fibres. A new three‐dimensional web structure has been examined as an alternative padding material, showing preliminary promising fire properties with regard to ignition time, heat release rates and smoke production. 相似文献
6.
Mauro Zammarano John R. Shields Isaac Leventon Ickchan Kim Shonali Nazare Andre Thompson Rick D. Davis Artur Chernovsky Matthew Bundy 《火与材料》2021,45(1):114-126
Herein, we describe a reduced‐scale test (“Cube” test), measuring the fire performance of specimens including a fire barrier (FB) and a flammable core material, which acts as the main fuel load. The specimen is intended to reproduce a cross‐section of a composite product where heat/mass transfer occurs primarily in a direction perpendicular to the FB. The Cube test procedure and benefits are discussed in this work by adopting residential upholstery furniture as an exemplary study. One flexible polyurethane foam, one polypropylene cover fabric, and 10 commercially available FBs were selected. They were used to compare the fire performance of FBs, measured in terms of peak of heat release rate, in the ASTM E1474‐14 standard test and the newly developed Cube test. Edge effects severely affected the performance of FBs in the ASTM E1474‐14 standard test but not in the Cube test. Furthermore, appropriate test conditions were determined in the Cube test to measure the so‐called “wetting point,” that is, the time and value of heat release rate measured when flammable liquid products were first observed on the bottom of the specimen. The relevance of the “wetting point” in terms of full‐scale fire performance and failure mechanism of FBs is discussed. 相似文献
7.
相邻工作面开采会导致复杂的漏风情况,浮煤易自燃,增大防火工作的难度。为明确相邻采空区自燃“三带”分布特征及确定最佳注氮防灭火参数,以贵州某矿4244工作面为背景,结合现场实测,应用Fluent流场分析软件,模拟研究不同注氮方案下采空区氧气浓度场分布规律。结果表明,实测结果与模拟相吻合,验证了模拟的可靠性;当注氮位置为X=50 m,注氮流量为100 m3/h时,采空区进、回风巷侧氧化带宽度分别为7 m和38 m,能明显减少本采空区氧化带面积,且能防止氧化带距工作面太近;此工作面进风侧注氮对相邻采空区氧化带影响范围较小,这要求在回采过程中需要对煤柱进行加固,降低孔隙率,控制漏风,减少氧气进入相邻采空区,降低煤自燃风险。模拟结果为相邻采空区灾害防治工作提供了的理论指导。 相似文献
8.
为解决魏家地煤矿工作面煤层透气性系数低,采空区瓦斯治理难的安全生产问题,以该矿北1103工作面为工程背景,采用数值模拟和现场实践等方法,对地面钻孔瓦斯抽采后,采空区自燃“三带”的变化规律进行了分析研究,并给出了相关自然发火对应防治措施。结果表明,北1103工作面经地面钻孔抽采瓦斯后,采空区散热带宽度由56 m增加至61 m;氧化带宽度由29 m增加至39 m;窒息带宽度由315 m减少至300 m。本次研究有效解决了北1103采空区瓦斯涌出量大与自然发火隐患问题。研究结果适用于魏家地煤矿采取综合立体瓦斯抽采治理模式的工作面,极大地保护了工作面安全回采,对落实矿井的安全高效生产及经济价值效益具有良好的工程示范意义。 相似文献
9.
由于型钢翼缘外露,部分包覆钢-混凝土组合(PEC)柱耐火极限很难满足设计需求。为探究PEC柱抗火性能加强方法,得到经济合理的加强措施,通过ABAQUS有限元分析软件建立了轴压作用下PEC柱的温度场及热力学性能有限元分析模型,并用已有试验数据验证模型可靠性,探讨了PEC柱在高温下的温度变化、受力机理和破坏模式。对不同加强措施下轴压PEC柱抗火性能进行了参数分析,研究了荷载比、纵筋配筋率、翼缘面积比、截面尺寸、长细比和防火涂料厚度等参数对PEC柱耐火极限的影响规律。结果表明:PEC柱耐火极限随荷载比、长细比、翼缘面积比的降低而明显提高,随着防火涂料厚度与截面尺寸的增加而明显提高; 在参数分析的基础上,回归得到考虑防火涂料厚度影响的PEC柱耐火极限简化计算公式,研究结果将为PEC构件抗火设计提供科学依据。 相似文献
10.
Aqueous film-forming foams (AFFFs) are an important for fire extinguishing, and their key ingredient is fluorinated surfactant. In recent years, traditional long-chain fluorinated surfactants have been banned by most countries because of their persistence, bio-accumulation and toxicity. Therefore, increased attention has been paid to the research and development of short-chain fluorinated surfactants. As is well known, the introduction of hydrophilic or hydrophobic groups in a surfactant affects its surface activity, and therefore, the fire extinguishing performance of AFFFs. In this work, a series of short-chain fluorosurfactant-based AFFFs with different hydrophobic chain lengths were prepared. The physicochemical performance of mixed systems (fluorinated surfactant plus sodium hexanesulfonate), including surface activity, spreading ability, foam expansion, drainage time, and the fire extinguishing and burn-back performance of AFFFs were studied. The results show that the critical micelle concentration (CMC) and the surface tension (γCMC) at the CMC of mixed systems at 25°C are lower than 7.68 mmol/L and 16.51 mN/m, respectively. For mixed systems, the average spreading rate is more than 1.09 cm/s, the foam expansion is over 7.1, and the drainage time is greater than 3.28 min. The fire extinguishing time of AFFFs on fuels is less than 51 s while the burn-back time is more than 15.18 min. The results imply a potential application prospect of the short-chain fluorinated surfactants in AFFFs. 相似文献