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61.
采用磷酸硼对木材进行改性处理,测定了处理后试材的阻燃性、抗流失性、吸湿性、力学性能.研究结果表明,磷酸硼处理后试材,吸药量达到20.47 kg/m3以上时,垂直燃烧实验可达到到F-0级水平;通过灼烧实验,磷酸硼处理的木粉在500℃灼烧时残留率可达到97.997%;此改性剂具有较好阻燃性能和一定的抗流失性,常压下磷酸硼处理的樟子松试件LRV为50.28%;木材顺纹抗压强度平均下降了 8.67%,无明显变化;木材抗弯曲压强度平均下降了 27.95%.但磷酸硼阻燃剂在高湿条件下有一定的吸湿性,使用性能有待改进,并应注意采取防护措施. 相似文献
62.
《国际聚合物材料杂志》2012,61(1):87-94
Abstract Intumescent fire retardants have wide applications due to thermo-protective properties, which decrease heat flow on the polymer surface. In this work we present the experimental investigation of thermal-protection properties of a number of polymer mixtures (polycarbonate + ABS plastic, epoxy resin, etc.) with different fire retardant additions. 相似文献
63.
研究了用火焰原子吸收法测定放射性废液固化体中模拟核素钌(Ru)。对Si,Fe,Al,Ca,Mg,K,Na等主要共存元素Ru测定的干扰及干扰的消除进行了研究。回收率达99.5%,同时试验确定以H2SO4为抗干扰及增感剂,取得较好的掩弊效果,并大大提高了测定的灵敏度,其吸收值比原来增加了2.5倍左右,本方法操作简便、迅速,可为放射性废液固化浸出试验提供准确的分析数据,适用于水泥及玻璃固化体中核素Ru的测定。 相似文献
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《Ceramics International》2017,43(18):16063-16069
Our previous research paper on geopolymer-mullite composites showed promising results on compressive strength and fire resistance. However, no improvement in thermal shock resistance was observed in the afore mentioned study. In this study, further attempts to improve thermal shock resistance of the geopolymer were explored. The research was performed by compositing a fly ash-based geopolymer with cordierite-mullite at 20, 40 and 60 wt% replacement. X-ray diffraction (XRD) of the cured geopolymer composite specimens showed the existence of cordierite, mullite, quartz, cancrinite and lazurite. It was found that compressive strength and strength retention after thermal exposure at 400 °C were improved in the geopolymer composite specimens, especially those with 20–40 wt% replacement. Upon further heating to 600 °C, all geopolymer specimens showed insignificant differences in compressive strength. Fire resistance was found to improve with increasing proportion of replacement contents. 相似文献
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Interaction of impact shock waves that could detonate an explosive (Composition B) confined in a thin-walled container impacted by a cone-nosed projectile is numerically studied, based on the Forest Fire explosive reaction rate model. The normal impact on the container by a small projectile with a conical nose is considered. Depending on the cone angle of the nose part of the projectile, the zone of interaction of initiating shock waves can be remote from the central axis of the impact. The off-the-central-axis detonation is interpreted from the viewpoint of different interaction modes in the explosive container, which are reflected from the cassette wall, change their directions, and superimpose onto each other, leading to explosive detonation. 相似文献
70.
Mechanical properties of high-strength concrete after fire 总被引:2,自引:0,他引:2
With compressive strength grade of C40, C60, and C70, respectively, normal-strength concrete (NSC) and high-strength concrete (HSC) were used to investigate compressive strength, splitting tensile strength, and bending strength after high temperature. The oil furnace is used in this study. Its temperature-time curve is close to standard curve, which conforms to Chinese standard GB/T 9978-1999. After being heated to temperatures of 200, 400, 600, 800, and 1000 °C, respectively, the mechanical properties of HSC were tested. The influence of temperature, water content, specimen size, strength grade, and temperature profiles on mechanical properties of HSC are discussed. 相似文献