机械力化学制备锡酸锌及其在PVC中的阻燃应用

以二氧化锡（SnO₂）和氧化锌（ZnO）为原料,通过机械力化学湿法球磨,制备了锡酸锌（ZS）,再与水滑石按一定比例研磨得到锡酸锌改性的水滑石（ZS/HT）。通过扫描电子显微镜、X射线衍射、透射电子显微镜对合成的ZS与ZS/HT做了表征。将制得的ZS/HT应用于PVC制得阻燃PVC样品,当加入10%（ZS与水滑石的质量比）ZS/HT时材料的极限氧指数比纯PVC样品高3.5%,同时材料的力学性能有所增加。热重分析结果表明,ZS/HT的加入促使PVC提前分解成炭,有效提高PVC材料的残炭量。     

高分辨连续光源原子吸收光谱法测定铀铌铅多金属矿中痕量银

铀铌铅多金属矿组成成分复杂,准确有效的测定其中的痕量银,有利于银的回收利用。采用HCl-HNO₃-HF-HClO₄处理铀铌铅多金属矿样品,以HCl(1+4)-2g/L酒石酸为测定介质,以λ_Ag=328.068nm为分析谱线,建立了高分辨连续光源原子吸收光谱法(HR-CS-AAS)测定铀铌铅多金属矿样品中痕量银的新方法。对仪器参数进行了优化,确定采用迭代基线校正(IBC)背景校正方式,CCD检测器有效像素点选择5个;由银的平均吸收光谱图和吸光度-波长-时间三维吸收光谱图可知,银的CCD检测器分辨率为0.0020nm/pixel,λ_Ag=328.068nm在327.86~328.27nm范围内没有受到溶液中其他共存元素的谱线干扰。在优化的实验条件下,银的吸光度与其质量浓度在0.40~1.60μg/mL范围内运用二次方程最小二乘法拟合校准曲线,相关系数为0.9999,特征浓度为0.0148μg/mL,方法检出限为0.0013μg/mL。将HR-CS-AAS测定样品中银的参数与空心阴极灯原子吸收光谱法(HCL-AAS)相比,其检出限更低,特征浓度更低,标准溶液系列的吸光度更高。按照实验方法对铀铌铅多金属矿样品中的银进行测定,结果与电感耦合等离子体质谱法基本一致,相对标准偏差(RSD,n=9)为0.63%~3.3%。按实验方法在铀铌铅多金属矿样品中加入银标准溶液进行加标回收试验,回收率为97%~104%,满足国家地质矿产行业标准DZ/T 0130—2006的要求。     

竹材液化墙体泡沫材料的阻燃改性

为提高竹材液化产物所制备的高轻发泡墙体材料的防火性能，分别采用材料内部添加和表面浸泡的方法进行阻燃改性，并评价不同阻燃剂及其添加量对发泡材料阻燃性能的影响。实验结果表明：在材料内部或表面添加选择的阻燃剂不会对材料自身形貌或组分产生明显影响，对材料的力学性能亦不会造成破坏，在材料内部添加3 g膨胀型凝胶-二氧化硅/聚磷酸铵核壳阻燃剂（MCAPP）后压缩强度达到了0.37 MPa，在材料表面浸泡聚硅氧烷后压缩强度达到了0.58 MPa，同时能提高材料的阻燃性能，在材料内部添加聚磷酸铵（M-APP）后极限氧指数提高到33.2%，比改性前提高3%。在材料表面浸泡膨胀型壳聚糖-蒙脱土-聚磷酸铵（CMAp）后点燃时间明显延长，极限氧指数最高达到了31.5%。     

Flame extension and the near field under the ceiling for travelling fires inside large compartments

Structures need to be designed to maintain their stability in the event of a fire. The travelling fire methodology (TFM) defines the thermal boundary condition for structural design of large compartments of fires that do not flashover, considering near field and far field regions. TFM assumes a near field temperature of 1200°C, where the flame is impinging on the ceiling without any extension and gives the temperature of the hot gases in the far field from Alpert correlations. This paper revisits the near field assumptions of the TFM and, for the first time, includes horizontal flame extension under the ceiling, which affects the heating exposure of the structural members thus their load-bearing capacity. It also formulates the thermal boundary condition in terms of heat flux rather than in terms of temperature as it is used in TFM, which allows for a more formal treatment of heat transfer. The Hasemi, Wakamatsu, and Lattimer models of heat flux from flame are investigated for the near field. The methodology is applied to an open-plan generic office compartment with a floor area of 960 m² and 3.60 m high with concrete and with protected and unprotected steel structural members. The near field length with flame extension (fTFM) is found to be between 1.5 and 6.5 times longer than without flame extension. The duration of the exposure to peak heat flux depends on the flame length, which is 53 min for fTFM compared with 17 min for TFM, in the case of a slow 5% floor area fire. The peak heat flux is from 112 to 236 kW/m² for the majority of fire sizes using the Wakamatsu model and from 80 to 120 kW/m² for the Hasemi and Lattimer models, compared with 215 to 228 kW/m² for TFM. The results show that for all cases, TFM results in higher structural temperatures compared with different fTFM models (600°C for concrete rebar and 800°C for protected steel beam), except for the Wakamatsu model that for small fires, leads to approximately 20% higher temperatures than TFM. These findings mitigate the uncertainty around the TFM near field model and confirm that it is conservative for calculation of the thermal load on structures. This study contributes to the creation of design tools for better structural fire engineering.     

线性富磷化阻燃剂在聚氨酯泡沫中的应用研究

通过界面聚合法合成了一种线性富磷化阻燃剂（LPRFR），将LPRFR与可膨胀石墨（EG）复配制备了阻燃聚氨酯泡沫（RPUF），使用红外光谱分析仪、核磁共振分析仪对阻燃剂LPRFR的化学结构进行了表征，并通过极限氧指数仪、锥形量热仪、扫描电子显微镜和红外光谱分析仪对RPUF的燃烧性能、微观形貌和化学结构进行了分析。结果表明，仅10 %（质量分数，下同）的LPRFR 与8 %EG复配后，RPUF的极限氧指数（LOI）便达到26.1 %；LPRFR和EG能大幅降低RPUF的热释放速率，并提高基体的成炭能力； LPRFR参与了燃烧过程中的成炭反应，形成了含P—O—C及P=O结构的高质量炭层，有效隔绝了氧气和热量；LPRFR是一种对于聚氨酯泡沫阻燃性能优异的新型阻燃剂。     

Numerical Study on the Morphology of a Re-Ignited Laminar Partially Premixed Flame with a Co-Axial Pilot Flame

Re-ignited partially premixed flame(PPF)is a quite extensive flame type in real applications,which is directly relevant to the local and global extinction and re-ignition phenomenon.The authors designed a model burner to establish laminar re-ignited PPFs.Numerical simulations were carried out to reveal the morphology of laminar re-ignited PPF.Based on the distributions of temperature,heat release and radicals,the morphologies of re-ignited flames were explored.W-shaped flames were formed under pilot-lean conditions.Line-shaped and y-shaped flames were formed under pilot-rich conditions.Both w-shaped and y-shaped flames had a triple-flame structure.The re-ignited flames can stand beyond the rich flammability limit.Additionally,OH distributions indicated both pilot flame and re-ignited flame well as it rapidly increased near the flame front.OH concentration did not increase visibly while CH2O concentration mildly increased during the mild re-ignition process in the pre-zone of the re-ignited PPF.According to the results of 0-D simulations using closed homogeneous reactor,both OH and CH2O reduced ignition time significantly.The results of this work are helpful for understanding re-ignited PPF more closely.     

壳聚糖改性聚乳酸的阻燃性能分析

为解决聚乳酸(PLA)易燃、熔滴等问题,以绿色天然高聚物壳聚糖为原料,采用甲磺酸、五氧化二磷、三聚氰胺对其改性,得到了一种绿色环保型阻燃剂———MPCS,与三聚氰胺聚磷酸盐(MPP)复配,形成了膨胀型阻燃剂(IFR)。将IFR、α-磷酸锆(α-ZrP)和PLA用转矩流动仪熔融共混制备了阻燃聚乳酸复合材料。采用傅立叶红外光谱(FT-IR)、X射线粉末衍射(XRD)对MPCS的结构进行了表征;用垂直燃烧法(UL-94)、锥形量热测试(CCT)、热重分析(TGA)及电子扫描电镜(SEM)研究了聚乳酸复合材料的阻燃性能及其阻燃机理。结果表明,当添加3%α-ZrP和22%IFR时,PLA复合材料的阻燃性能达到UL-94V-0级且无熔融滴落;由于α-ZrP具有片层阻隔作用和催化成炭作用,α-ZrP能提高PLA/IFR复合材料的阻燃效果,降低热释放量和烟密度。     

亚磷酸酯功能化聚硅氧烷扩链聚乳酸的阻燃性能研究

将聚氨基环氧基硅氧烷（PSQ）以及亚磷酸酯功能化的聚氨基环氧基硅氧烷（PPSQ）与聚乳酸（PLA）通过熔融共混制备了扩链PLA。研究了亚磷酸酯基团的引入对PSQ在PLA中的扩链和阻燃性能的影响，探究PPSQ在PLA中的阻燃机理。结果表明，相比于PSQ，PPSQ可以明显提高PLA的分子量和复合黏度，具有更好的扩链作用；PPSQ的引入可以明显改善PLA的阻燃性能，使得PLA?PPSQ的极限氧指数提高至25.4 %，比纯PLA提升了31.6 %，且使得PLA的热释放速率峰值和总热释放量分别下降了18.1 %和16.6 %。分析可知，由于亚磷酸酯基团的引入，促使PLA?PPSQ中的硅元素在燃烧过程中向炭层表面迁移形成更多富含碳化硅和氧化硅的致密炭层，起到隔热隔氧的作用，进而发挥优异的阻燃性能。     

料仓皮带机电子秤在烧结生产工艺中的应用--一种模块式计量托辊电子皮带秤的应用实践

烧结生产,是钢铁工业的重要环节。烧结矿生产的各种矿料、燃料、辅料配比和烧结矿成品需要称重计量。烧结料配料与烧结矿成品基本是采用皮带机输送,烧结矿生产物料适宜采用电子皮带秤计量。为简化电子皮带秤的结构,降低安装和维护工作量,可将皮带机的上托辊,采用模块式计量托辊代替,可组合组装成多段计量的电子皮带秤。模块式计量托辊,可安装到原皮带机或原皮带电子秤,替代原托辊或原计量托辊。简化电子皮带秤的结构和安装,减少安装与维护工程量。嵌入式计量托辊模块,为发明专利产品。