烟草燃烧行为的研究进展

烟草的燃烧过程复杂,学者们利用热裂解-气相色谱-质谱联用技术（PY-GC-MS）、热重分析仪（TG）和热重-红外-气质（TG-IR-GC-MS）联用等热分析技术,从不同方面对烟草的燃烧行为进行研究。本文综述了国内外有关烟草燃烧行为的研究进展,分别从燃烧机理、燃烧行为学、热分析计算模型以及研究烟草燃烧所采用的热分析技术这四个方面进行了概述。并对研究烟草燃烧行为方面进行了总结和展望。     

核燃料热行为的热分析研究

本文介绍了下列几种实验研究:用热分析法研究制备快堆低密度燃料芯块的六种造孔剂的热分解过程;U_3Si_2在氮气、氩气气氛中的热稳定性。     

季铵盐离子液体的合成及表征

以三乙胺和苄氯为原料,通过中间体氯化苄基三乙胺盐([Nbz222]Cl)的阴离子交换反应合成了5种目标产物:苄基三乙胺四氟硼酸盐([Nbz222]BF4),苄基三乙胺六氟磷酸盐([Nbz222]PF6),苄基三乙胺硫酸氢盐([Nbz222]HSO4),苄基三乙胺磷酸二氢盐([Nbz222]H2PO4)和苄基三乙胺咪唑盐([Nbz222]Im),产物的结构通过FTIR、1HNMR、13CNMR、ESI-MS、元素分析得以确认。除[Nbz222]PF6之外,其余4种目标产物的熔点均低于100℃。热分析表明,目标离子液体的热稳定性顺序为:[Nbz222]HSO4>[Nbz222]BF4>[Nbz222]Im>[Nbz222]H2PO4,其中[Nbz222]HSO4具有较好的热稳定性,热分解温度在260℃左右。目标离子液体均有一定的吸水性并在极性溶剂中有较好的溶解性。     

Global rupture of a nuclear reactor lower head with elevated temperature due to severe accidents

This paper is concerned with the global rupture of a reactor pressure vessel (RPV) with elevated temperature due to severe accidents in order to check if the RPV wall can retain the high-elevated pressure. The global rupture of an RPV is simulated by finite element limit analysis for the collapse load and mode to secure the safety criteria of a nuclear reactor under severe accident conditions. Finite element limit analysis is a systematic tool dealing with upper bounding and minimization technique to calculate the collapse load and mode. The finite element code (CALF, computer analysis of lower head failure) developed provides the temperature elevation in the lower head of a nuclear reactor under severe accident conditions as well as the collapse load and mode. The thermal analysis has to deal with heat transfer from the debris pool to the RPV wall and the top of the pool. The temperature distribution in such a system depends sensitively on the initial temperature of the debris pool and the thermal properties of a gap between the debris crust and the RPV wall. For accurate calculation, the thermal properties of a gap have to be determined in consideration of the gap size and conditions.     

中高分子量聚乙二醇的热分析研究

本文利用热分析仪通过ＤＳＣ对所合成的中高分子量聚乙二醇（ＰＥＧ）进行了熔融过程的热力学参数（Ｔｍ、△Ｈｍ）测定，得出了其随分子量变化的规律，并利用其在氧化裂解过程中的热失重曲线（ＴＧ）进行动力学参数（Ｅ、ｎ、Ａ）测定和热稳定性的研究。     

发热保温冒口性能的研究进展

论述了发热保温冒口的各项性能对其补缩效果的影响,以及各种新型材料在发热保温冒口中的应用,重点论述了发热保温冒口热物理性能测试技术的最新进展,并根据存在的问题,展望了今后的研究方向。     

Solid state synthesis and sintering of solid solutions of BNT–xBKT

Various compositions of the solid solution system (100 − x) Bi_0,5Na_0,5TiO₃–xBi_0,5K_0,5TiO₃ (x = 0, 10, 25, 50, 75, 90, 100) were prepared by the mixed oxide route. The formation reaction was analyzed by thermogravimetry coupled with mass spectroscopy and differential scanning calorimetry. In situ high temperature X-ray diffraction up to 770 °C indicated emerging and vanishing of phases during the calcination. Intermediate phases such as alkalipolytitanate (Na/K)₂Ti₆O₁₃ and bismuth titanate Bi₂Ti₂O₇ were identified as forming the perovskite phase. The formation reactions were proposed based on the data obtained. Furthermore the microstructure and the dielectric behavior of the sintered samples were observed by scanning electron microscopy, impedance spectrometry and polarization measurements.     

双吡唑啉酮类新型萃取剂BPMOPH与铀（VI）的固体配合物研究

合成了新型双β-二酮类螯合剂1,6-双(1′-苯基-3′-甲基-5′-氧化吡唑-4′-基)己二酮-[1,6]与铀(Ⅵ)的固体配合物。由元素分析和热谱分析确证了配合物的组成;进一步研究了固体配合物的质子核磁共振谱、红外光谱和紫外吸收光谱,从而得到了螯合剂与铀(Ⅵ)配位方面的信息。     

Synthesis,Characterization and Thermal Behaviour of Guanidinium‐5‐aminotetrazolate (GA) – A New Nitrogen‐Rich Compound

This work describes the synthesis and the thermoanalytical characterization of guanidinium‐5‐aminotetrazolate (GA). GA is a new nitrogen‐rich energetic material. It is not mentioned in the chemical literature so far. The molecular structure of the compound has been determined by IR, ¹H‐, ¹³C‐ and ¹⁵N‐NMR spectroscopy. The thermal properties, the decomposition pathways and its volatile products were investigated by thermal analysis and are discussed.