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131.
Effect of nitrogen–phosphorus fire retardant blended with Mg(OH)2/Al(OH)3 and nano‐SiO2 on fire‐retardant behavior and hygroscopicity of poplar
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The aim of the study was to screen any possible synergistic effects related to the combination of nitrogen–phosphorus fire retardant and Mg(OH)2/Al(OH)3. This combination is used to improve fire performance, especially smoke suppression of poplar through ultrasonic wave impregnation after microwave treatment. In this study, nano‐SiO2 was used to impregnate poplar treated with nitrogen–phosphorus fire retardant and form a hydrophobic layer on wood cells in order to improve hygroscopicity and reduce water uptake. Cone tests and thermal analysis showed that poplar treated with blended fire retardant had improved behavior. Results show that a 20% and 25% nitrogen–phosphorus fire‐retardant solution (blended by adding 10% Mg(OH)2/Al(OH)3 based on the dry weight of nitrogen–phosphorus fire retardant) was more effective for smoke suppression. The heat release rate, total heat release, and total smoke production of a 25% nitrogen–phosphorus fire‐retardant solution blended by adding 10% Mg(OH)2/Al(OH)3 showed significant reduction. The char residual yield showed a marked increase to 35.5%. Fourier transform infrared analysis suggested a –CH2–Si–CH2– and Si–O–C stretching vibration in nano‐SiO2 treated poplar, which greatly decreased the hygroscopicity of fire‐retardant‐treated poplar. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
132.
A novel hot aerosol extinguishing agent (HAEA), which is the combination of pyrotechnics and flame retardant technology, was found to have great efficiency in extinguishing Class B fires. A mixture of P and P3N5, referred to as P90x, was chosen as the reductant, and phase stabilized ammonium nitrate was chosen as the oxidant. This paper describes a study of the effectiveness of this agent in extinguishing n‐heptane fires (ie, Class B fires). We determined that the best efficiency was 15 g/m3 for extinguishing n‐heptane fires, four times more efficient than a traditional agent. The efficiency increases as the mass fraction of P90x rises. We also identified the key difference between the novel extinguishing agent and the traditional agent. The former consists of an inorganic phosphorus compound, while the latter is mainly comprised of KOH. Consequently, their extinguishing mechanisms are different. The phosphorus oxide of the novel HAEAs is the leading component to extinguish fire, which is more effective than alkali salts. 相似文献
133.
《International Journal of Hydrogen Energy》2022,47(2):1016-1025
The development of hydrogen evolution activity (HER) electrocatalyst that can run durably and efficiently under the large current density is of special significance but still challengeable for the massive production of hydrogen. Herein, a CoP/Ni(OH)2 nanowire catalysts grown on Co foam (CF) with a three-dimensional heterojunction structure has been successfully prepared by electrodepositing nickel hydroxide on the surface of cobalt phosphide. The prepared CoP/Ni(OH)2–15 min sample reveals a superior HER activity and stability. It merely requires ultralow overpotentials of 108 and 175 mV to 100 and 500 mA cm?2, respectively. In addition, the long-term stability test shows that the catalyst (CoP/Ni(OH)2–15 min) can operate stably for at least 70 h at 400 mA cm?2. Utilizing NiFe-LDH/IF with high OER activity, the NiFe-LDH/IF || CoP/Ni(OH)2–15 min catalyst system possesses the same outstanding performance for overall water splitting (OWS), which can accomplish ≈ 500 mA cm?2 at 1.74 V in 1 M KOH electrolyte. Moreover, the NiFe-LDH/IF || CoP/Ni(OH)2–15 min couple can work for more than 80 h at 500 mA cm?2, indicating its a great prospect in the area of electrolysis water. Such excellent catalytic performance is mainly attributed to the armor effect of Ni(OH)2, which can not only promote the rapid decomposition of water molecules, but also prevent the loss of phosphorus and enhance the synergistic effect of CoP and Ni(OH)2. This work can offer a significant reference for the design with high-performance and durable transition metal phosphide electrocatalysts. 相似文献
134.
本文针对现有国标分析方法 GB/T 8704.7-2009钼蓝光度法测定钒铁中的磷含量方法存在操作繁琐、流程长、重现性差,准确度低、成本较高等问题进行了改进。通过采用硫酸加硝酸溶样,用亚硫酸钠还原钒为统一的4价,采用对应试液作参比消除钒的干扰等手段,使钒铁中磷的含量的测定方法变得操作简便、快速、准确、成本下降。 相似文献
135.
介绍了几种钢铁中磷含量的测定方法,着重对铋磷钼蓝分光光度法进行了研究,阐述了实验所需仪器、试剂以及实验试剂制备流程,通过探讨实验的准确度与精密度,得出了一些有意义的结论。 相似文献
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137.
A novel scheme for denitrifying biological phosphorus removal via nitrite from nutrient‐rich anaerobic effluents in a short‐cut sequencing batch reactor
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Metal‐Organic Frameworks: From Bimetallic Metal‐Organic Framework to Porous Carbon: High Surface Area and Multicomponent Active Dopants for Excellent Electrocatalysis (Adv. Mater. 34/2015)
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