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排序方式: 共有157条查询结果,搜索用时 27 毫秒
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三聚氰酸为基的2,4,6-三氧-[1,3,5]三嗪烷-1-三氨基胍盐的合成、晶体结构和热性能(英) 总被引:1,自引:1,他引:0
以三聚氰酸钠(CANa)和三氨基胍盐酸盐(TAG-HCl)为原料,通过一步复分解反应制备了一种富氮含能化合物——2,4,6-三氧-[1,3,5]三嗪烷-1-三氨基胍盐(1),收率91%.采用X-射线单晶衍射、UV-Vis、FTIR、1H NMR以及元素分析等对产物进行了结构表征.计算了产物的生成焓和爆轰参数.通过差示扫描量热法(DSC,10 K·min-1)和热重-傅里叶变换红外光谱联用分析了其热稳定性、非等温热分解动力学和热分解过程.通过落锤法测试了产物的撞击感度.结果表明,化合物1的晶体为单斜晶系,P21/n空间群,计算密度为1.676 g·cm-3,生成焓为327.9 kJ·mol-1,爆速为7900 m·s-1,爆压为26.5 GPa.化合物具1有良好的热稳定性,分解峰值温度为538.9 K,提出了N2气氛下可能的热分解机理.且化合物1对撞击非常钝感,撞击感度大于60 J,优于TATB(50 J). 相似文献
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在己内酰胺开环水解过程中,加入一定量的聚{[6-[(1,1,3,3-四甲基丁基)氨基]]-1,3,5-三嗪-2,4-[(2,2,6,6-四甲基-哌啶基)亚氨基]-1,6-己二撑[(2,2,6,6-四甲基-4-哌啶基)亚氨基]}(UV–944),合成改性聚酰胺6。研究了UV–944对聚酰胺6光稳定性、热氧稳定性和末端氨基含量的影响。结果表明,UV–944的加入能明显提高聚酰胺6的耐紫外光老化及热氧稳定性,在空气氛围下的起始分解温度提高28℃左右;在185℃老化0.5 h后,改性聚酰胺6的相对黏度下降极低(UV–944质量分数为0.05%时,相对黏度仅下降了3.1%),热氧稳定性明显得到改善。同时,聚酰胺6的末端氨基含量增加,加入UV–944质量分数分别为0.05%,0.2%时,聚酰胺6的末端氨基含量比纯聚酰胺6提高5.1,18.7 mmol/kg,对染色性能明显有所改善。而UV–944对聚酰胺6的热稳定性、熔融温度与结晶温度影响不大。 相似文献
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对噻虫嗪中间体3-甲基-4-硝基亚胺基四氢-1,3,5-噁二嗪的合成进行研究。通过优化反应条件,使产品转化率达到90%以上,同时收率也能达到85%以上,高于以往的文献报道值。该方法操作简便,适用于工业化生产。 相似文献
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Chun‐jiang An Yan‐ling He Guo‐he Huang Shu‐cheng Yang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(6):831-838
BACKGROUND: This study investigated the performance of anaerobic mesophilic granular sludge for the degradation of hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine (RDX). Batch tests were conducted to investigate the effects of different supplements on the RDX degradation ability of anaerobic granular sludge, as well as the contributions of both physicochemical and biological processes involved in RDX removal from aqueous solution. RESULTS: Anaerobic granular sludge exhibited good performance in treating RDX as the sole substrate. Biodegradation was the main mechanism responsible for RDX removal. Ammonium had no significant promoting effect on the degradation process. The presence of glucose was found to enhance the degradation of RDX by anaerobic granular sludge, while the addition of sulfate and nitrate had adverse effects on the reductive transformation of RDX. CONCLUSIONS: Anaerobic granular sludge is capable of removing RDX from aqueous solution with high efficiency. This study showed good prospects for high‐rate anaerobic processes in the treatment of munition wastewater. The results can be used for the design and optimization of high rate anaerobic systems for the elimination of RDX. Copyright © 2010 Society of Chemical Industry 相似文献
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Quantum chemical studies have gained paramount importance in screening of thermodynamically feasible chemical processes. The current investigation attempts to select an appropriate process for the synthesis of 1,3,5-triamino-2,4,6-trinitro benzene (TATB), a reasonably powerful insensitive high explosive (IHE) through density functional theory (DFT) calculations. Although, 1,3,5-trichlorobenzene (TCB) and 1,3,5-trihydroxybenzene (THB) routes for synthesis of TATB have been well established, this article demonstrates the predictive capability of thermochemical computations for the identification of a viable process. Thermochemical parameters of reaction species have been obtained from DFT B3LYP/6-31G? calculations and feasibility of the process has been worked out on the basis of free energies of reactions and equilibrium constant as derived from standard enthalpy and entropy of the reaction species. The detailed computational studies have revealed that the THB route is thermodynamically feasible and the same has been supported experimentally. 相似文献
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Byeongjin Baek 《Electrochimica acta》2010,55(9):3307-44
This work presents a method of enhancing the kinetics of the interfacial reaction using 1,3,5-trifluorobenzene (TFB) which is used as an electron acceptor due to its locally biased polarity and as a source of rearranging the layer of the electrolyte around LiCoO2 electrode, not a SEI layer source. The full cells with TFB show a decrease in irreversible capacity loss during the first charge-to-discharge process, regardless of the SEI layer formation, and also show better discharge properties even at high rate conditions. The charge transfer resistance (Rct) of the LiCoO2 half cell with TFB shows the smaller resistance than that of the TFB free half cell, and the activation energy calculated from the Rct was 24.7 kJ/mol for the TFB free half cell and 19.3 kJ/mol for the half cell with TFB. In addition, the film resistance of the half cell with TFB shows higher value when the temperature is below 283 K. Since Rct is related to the transfer resistance of the solvated Li+ ions on the surface of the LiCoO2 electrode, it will help design the electrolyte to improve the transfer velocity of Li+ ions around the cathode electrode for high power Li ion battery. 相似文献