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K2CO3-Na2CO3-H2O三元体系288 K相平衡研究 总被引:3,自引:0,他引:3
采用等温溶解平衡法研究了三元体系K2 CO3 -Na2 CO3 -H2 O 2 88K时的相平衡及平衡液相的主要物化性质 (密度 ,电导率 ,pH)。研究发现 :该三元体系有复盐NaKCO3 ·6H2 O形成 ,根据溶解度数据绘制了相图 ,相图中有 2个共饱点E、F ,三条单变度曲线AE、BF、EF ;平衡固相分别为K2 CO3 ·3/ 2H2 O、Na2 CO3 ·10H2 O、NaKCO3 ·6H2 O。实验结果表明K2 CO3 对Na2 CO3 有强烈的盐析作用 ;并简要讨论了实验结果。 相似文献
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KF/K2CO3/γ-Al2O3催化合成肉桂酸 总被引:1,自引:0,他引:1
以苯甲醛和丙二酸为原料,KF/K2CO3/γ-Al2O3为催化剂,经Knoevenagel反应,在无溶剂条件下催化合成了肉桂酸。产品用IR、1HNMR及元素分析进行表征。考察了催化剂用量、苯甲醛与丙二酸摩尔比和反应时间对肉桂酸收率的影响。结果表明:KF/K2CO3/γ-Al2O3具有良好的催化活性,较佳工艺条件为:苯甲醛10.2 mL(10.6 g,0.1 mol),n(苯甲醛)∶n(丙二酸)=1∶1.15,催化剂KF/K2CO3/γ-Al2O3用量2.5 g(含KF4.68 mmol),反应60 min,肉桂酸的平均收率达到92%以上。 相似文献
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钠基固体吸收剂脱除燃煤烟气CO2技术具有反应温度低、能耗低等优点,日益受到学术界的关注。该技术的主要不足是吸收剂的活性成分碳酸钠与CO2的反应(碳酸化反应)活性较低。针对这一问题,本文旨在研制一种新型改性钠基固体吸收剂,采用活性氧化铝作为载体、TiO2作为掺杂剂进行改性,利用热重分析装置、XRD、SEM和氮吸附仪研究钠基固体吸收剂的CO2捕捉性能。结果表明:掺杂TiO2后,钠基固体吸收剂与CO2的反应速率加快,CO2捕捉量增加;反应前后除TiO2外无其他含Ti化合物生成;碳酸化反应产物为NaHCO3和Na5H3(CO3)4;然而TiO2掺杂过多会堵塞吸收剂的微观孔道,不利于甚至阻碍碳酸化反应的进行,因此,TiO2的掺杂量应控制在一定的范围内。 相似文献
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采用一步离子交换法制备离子交换钢化玻璃.研究熔盐K2CO3含量对钢化玻璃的性能影响.离子交换时间设定在20 h,离子交换温度设定为380℃,熔盐的K2CO3含量分别设定为0%、1%、2%、3%、4%.离子交换工艺完成后,对化学钢化玻璃进行电子探针测试,表面应力测试,抗折强度测试,显微硬度测试,以分析熔盐K2 CO3含量的改变对化学钢化玻璃所产生的影响.数据结果显示:熔盐的K2CO3含量的变化会对化学钢化玻璃的机械性能产生较大影响.在离子交换过程中K+的扩散系数随着K2CO3含量的增大先增大后减小,Na+的扩散系数随着K2 CO3含量的增大逐渐增大.应力层深度DOL在K2CO3含量为1%时有最大应力深度;表面应力CS在K2CO3含量为3%时有最大值.抗折强度随着K2CO3含量的增大先升高后下降,最大值在K2CO3含量为2%处;显微硬度呈现先升高后下降的趋势,最大值在K2CO3含量为3%处.将交换熔盐的K2CO3含量控制在2%至3%之间能够得到最佳的综合力学性能. 相似文献
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利用热重分析仪、扫描电镜和氮吸附仪对不同粒径的K2CO3颗粒和负载型K2CO3/Al2O3二氧化碳吸收剂的碳酸化特性进行研究。负载后的吸收剂比表面积和孔隙结构得到较大改善,使得碳酸化反应速率和转化率均提高,吸收剂碳酸化特性得到改善。纯K2CO3颗粒吸收剂的反应速率和转化率随着粒径的增加而减小,负载型吸收剂的反应速率和转化率随着粒径的增加略增大。研究了不同粒径和反应时间对K2CO3/Al2O3颗粒微观结构的影响,结果表明K2CO3/Al2O3颗粒具有较稳定的微观结构。采用负载型粒子模型对K2CO3/Al2O3吸收剂吸收CO2碳酸化过程进行研究,所建立的粒子模型计算结果与试验值吻合较好。利用建立的模型对不同CO2浓度下K2CO3/Al2O3吸收剂碳酸化反应特性进行模拟计算,模拟结果具备一定的合理性和准确性,为开展进一步研究提供了基础。 相似文献
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比较了硼酸、磷酸脒基脲两种阻燃剂对绝缘纸热降解过程、剩炭率、击穿电压的影响,结果表明:①阻燃处理的绝缘纸热降解起始温度提前,硼酸提前约20℃,磷酸脒基脲提前约50℃;②硼酸处理的绝缘纸剩炭率升高到18.92%,磷酸脒基脲处理的升高到30.79%;③击穿电压:硼酸维持不变,磷酸脒基脲下降100 kV。同时考察两阻燃剂复配比例对绝缘纸阻燃效果的影响,结果表明,复配阻燃剂中硼酸含量在10%~20%阻燃效果、绝缘性最佳。并通过热重分析方法,对阻燃剂,绝缘纸以及浸渍处理前后绝缘纸的热降解过程进行了比较,从热降解的角度分析阻燃效果的差异。 相似文献
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通过氧指数、垂直燃烧等级及产烟率测定研究了氢氧化铝(ATH)、氢氧化镁(MH)、膨胀石墨(EG)、膨胀型阻燃剂(IFR)等以单一或协同复配的形式对酚醛树脂(PF)体系阻燃性能的影响,并采用差热分析(DTA)对体系的微观热行为进行了研究。结果表明,放热量最小的体系为ATH/MH/EG/PF,ATH/MH/EG/IFR/PF体系的氧指数最大,达到96。ATH/MH/PF体系的产烟率最低(72%)。添加阻燃剂后,体系的垂直燃烧等级可提高到UL94V-0级。 相似文献
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Imparting good flame retardancy and mechanical properties to epoxy resin (EP), while pursuing the sustainable and safe application of EP, we synthesized a novel reactive phosphorus/nitrogen flame retardant for biomass through nucleophilic addition reaction, which contains flexible ether bonds and rigid aromatic ring structure (DVD). Owing to the cooperative effect of aryl ether diamine, phosphorus phenanthrene, and biomass vanillin, the DVD exhibited excellent flame retardancy. EP/DVD-1 (0.4 wt% phosphorus content) achieved UL-94 V-0 rating, with an improvement in limiting oxygen index value from 26.5% (pure EP) to 32.5%. In the CCT, the modified DVD EP showed a 44.5% reduction in peak peak of heat release rate (PHRR) and a 38.0% reduction in total heat release compared to pure EPs. And flame retardant epoxy resin (FREP) still had good transparency after the addition of DVD, which indicated the nice compatibility between DVD andEP. What was noteworthiness was that at high levels of addition, the mechanical properties of modified EP for DVD was still improved compared to pure EP. These results demonstrate that DVD is an excellent and multifunctional bio-based flame retardant with broad application prospects in the field of EP material modification. 相似文献
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酚醛在丙烯酸树脂防火改性中的应用 总被引:2,自引:0,他引:2
以酚醛树脂为主防火剂、胺类为协效剂,研究了其种类、用量对丙烯酸树脂防火性能的影响,采用锥形量热仪和热重分析仪对酚醛改性丙烯酸树脂的燃烧性能和热稳定性进行了测试,并对燃烧后的炭层结构进行了电镜分析。结果表明,硼酚醛树脂能显著提高丙烯酸树脂的防火性能,硅酸铝、六次甲基四胺具有有良好的协效作用;当丙烯酸树脂与硼酚醛树脂质量比为50:50,硅酸铝质量分数为7%,六次甲基四胺为2%时,改性树脂耐燃时间达到39min,点燃时间(TTI)及热释放速率峰值出现时间明显延长,热释放速率明显降低,800℃时残炭率为45%,热稳定性明显提高,燃烧烧后形成了表面为致密网状、断面为微细泡孔状的炭层结构,防火性能提高。 相似文献
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In this study, a halogen‐free phosphorous‐nitrogen synergistic flame retardant, poly‐N‐aniline‐phenyl phosphamide (PDPPD), was synthesized. Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, and elemental analysis data confirmed the structure of PDPPD. The essential FR PA66 was polymerized with PA66 pre‐polymer and PDPPD pre‐polymer, prepared from PDPPD and adipic acid. The limit oxygen index and UL‐94 test results of FR PA66 reached 28% and V‐0, respectively, when the contents of PDPPD pre‐polymer were 4.5 wt%. The thermo‐gravimetric and differential scanning calorimetry results demonstrated that the initial decomposition temperature of FR PA66 was 43 °C lower than that of pristine PA66 from 385 to 342 °C; however, the peak decomposition temperature was 36 °C higher than that of pure PA66 from 437 to 473 °C, when the contents of PDPPD pre‐polymer reached 4.5 wt%. Flame retardant mechanism was studied by cone calorimeter testing and SEM‐EDX, confirming that the heat release rate (HRR), total heat release (THR), and total smoke product (TSP) decreased slightly, and PDPPD followed the gas phase flame retardant mechanism. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Wood‐based polymer composites represent a growing interest in the building industry. The fire response of this composite type is a concern to many end users. This study utilizes wood sawdust as reinforcement to develop flame retarded wood sawdust polyester composite (WSPC) panel. Flame retardant (FR) chemicals such as aluminium tri‐hydroxide (ATH), intumescent FR (ammonium polyphosphate [APP] Gum Arabic Powder [GAP]), and the combination of ATH and APP‐GAP (hybrid) at 0%, 12%, and 18% were used to modify the WSPC panel using hand lay‐up compression moulding technique. Tensile and flexural properties, thermal and flammability properties, and macroscopic image observations (MIOs) were examined using universal testing machine, thermogravimetric analysis (TGA/DSC), and the cone calorimeter apparatus (CCA), respectively. The results obtained show that the added nonhybrid FR in the WSPC panel enhanced the tensile and flexural strength while a reduction in the tensile modulus was observed. In the thermal stability, TGA analysis reveals that the added hybrid FR did not exhibit significant change in the thermal stability of the WSPC panel while cone calorimeter results show significant improvement in some fire properties. It can be concluded that the hybrid FR when incorporated in WSPC panel can be of great benefit to the building industry. 相似文献
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