TKX–50的热稳定性能研究

采用TG（热重）–DSC（差热）、扫描电镜、红外光谱、原位XRD(X射线衍射)、激光粒度分析等测试手段对1, 1’–二羟基–5, 5’–联四唑二羟胺盐（TKX–50）在推进剂使用工况下的热稳定性能进行了研究。结果表明,TKX–50的热分解分两步,且分解初期质量线有很大波动,第一阶段分解的活化能为143.6 kJ/mol,峰温为232.17℃,第二阶段分解的峰温为250.47℃,TKX–50在70℃/空气条件下储存30 d,质量、形状尺寸、平均粒径和晶型均未发生明显变化,热稳定性较好。     

真空下活性煅白制备的反应动力学研究

利用自制动态测压装置对白云石在真空下热分解的反应动力学进行了研究。结果表明:白云石的热分解过程可分为第一、第二两个分解阶段,分别为碳酸镁组分的分解以及碳酸钙组分的分解。真空下白云石第一、第二分解阶段活化能分别为288.2、313.0 kJ·mol~(-1),均小于热重中测得的第一、第二分解阶段的活化能306.8、327.1 kJ·mol-1。真空的引入使得白云石热分解过程更加容易、更加充分。     

BAMO-AMMO的热行为及其与含能组分的相容性

采用DSC、TG-DTG程序升温法研究了3,3-二叠氮甲基氧丁环/3-叠氮甲基-3-甲基氧丁环共聚物(BAMO-AMMO)的热行为,并采用DSC法和真空安定性法考察了BAMO-AMMO与含能组分RDX、HMX、DNTF、CL-20、AP、Al、NG、DIANP的相容性.结果表明,BAMO-AMMO的热分解分两个阶段进行,第一阶段分解峰温为260.3 ℃,较硝化棉的分解峰温高51 ℃,热稳定性好;第二阶段分解峰温为401.7 ℃;BAMO-AMMO与RDX、HMX、CL-20、AP、Al、NG、DIANP均相容,可与上述物质混合应用于火药.     

苦味酸铋的合成、分解反应动力学及热安全性(英文)

合成了苦味酸铋配合物(Bi-PA),对其结构进行了表征,并用TG-DTG及DSC技术研究了化合物的热行为和分解反应动力学。结果表明,在TG曲线上出现一个最大的失重阶段,对应于DSC曲线上的最大放热峰。放热分解反应过程可以认为是化学反应,其机理方程的微分式为f(α)=3(1-α)[-ln(1-α)]2/3,动力学方程为dα/dt=1013.51(1-α)[-ln(1-α)]2/3e-1.96×104/T。反应阶段的活化熵(ΔS≠),活化焓(ΔH≠)及活化自由能(ΔG≠)分别为2.25J.mol-1.K-1,159.82kJ.mol-1及158.60kJ.mol-1。     

腐殖酸热分解动力学

采用热重分析法(DTA-TGA)研究了腐殖酸的热分解过程及其动力学,分析其DTA-TGA曲线可得:热分解反应发生在284.65~417.16℃;用红外光谱(FT-IR)、核磁氢谱(1H NMR)、核磁碳谱(13C NMR)对腐殖酸结构进行表征,用Flynn-Wall-Ozawa(F-W-O)法、Kissinger法及?atava-?esták法计算出腐殖酸热分解反应的表观活化能为210.83 kJ·mol-1,指前因子对数为17.55;确定了其热分解反应的级数和动力学参数,且热分解反应机理为二级反应;腐殖酸在氮气氛围下维持1min寿命的最高使用温度为278℃;同时,计算出腐殖酸样品热力学参数焓变、熵变及摩尔自由能变分别为67.99 kJ·mol-1、-164.83 J·(mol·K)-1和176.36 kJ·mol-1。     

聚5-乙烯基四唑的热行为及其与含能组分的相容性研究

采用DSC、TG-DTG程序升温法研究了聚5-乙烯基四唑(PVT)的热行为,并采用DSC法和真空安定性法考察了PVT与推进剂主要组分RDX、HMX、CL-20、DNTF、ADN、AP、A1和Mg的相容性.结果表明,PVT的热分解分2个阶段进行,第一阶段分解峰温为237.2℃,第二阶段分解峰温为281.2℃;PVT与RD...     

不同热分析方法研究B炸药的热分解

用差示扫描量热仪(DSC)、热重-微熵热重分析仪(TG-DTG)、动态真空安定性技术(DVST)和温度跃升傅里叶变换红外(T-Jump/FTIR)光谱测定法对B炸药在不同试验条件下的热分解行为进行了研究。结果表明,在50～400℃有一个吸热峰和放热峰,吸热峰与主体炸药TNT的熔化峰相一致,放热峰与主体炸药RDX的分解峰一致。在50～400℃有两个失重阶段,第一个失重阶段的失重量与主体炸药TNT的失重量一致,第二个失重阶段的失重量与主体炸药RDX一致,与DSC分析结果相符。B炸药在100℃/48h下的产气量为0.43mL/g,表明B炸药有好的热安定性。B炸药快速热裂解过程的含氮气相产物主要有NO、NH3、HCN和HONO。含碳气体产物主要有CO、CO2、HOCO和HCN。得到了这些产物相对摩尔浓度随时间变化的曲线。     

太根发射药的非等温热分解反应动力学

采用热重分析(TG)技术研究了含二缩三乙二醇二硝酸酯(TEGDN,太根)和硝化甘油(NG)的双基发射药TG0604在常压动态气氛下的非等温热分解反应动力学.结果表明,TG0604的热分解过程分两个阶段,第Ⅰ分解阶段反应机理服从一级Mample法则,动力学参数:Ea=79.09kJ·mol-1,A=107.40s-1,动力学方程为dα/dt=107.40(1-α)e-0.95×104 /T;第Ⅱ分解阶段的反应机理服从三级化学反应,F3,减速型a-t曲线,动力学参数:Ea=214.79kJ·mol-1,A=1021.49s-1,动力学方程为dα/dt=1021.19(1-α)3e-2.58×104 /T.由加热速率β→0的DTG曲线的初始温度(Te)和峰温(Tp)计算出太根发射药TG0604的热爆炸临界温度值Tbe和Tbp分别为461.51K和478.14K.计算两个阶段的△S≠、△H≠和△G≠值,第Ⅰ阶段分别为-86.70J·mol-1·K-1、80.54kJ·mol-1和417.98kJ·mol-1;第Ⅱ阶段分别为214.78J·mol-1·K-1、236.95kJ·mol-1和136.07kJ·mol-1.     

十氢十硼酸双四乙基铵热分解特性及其动力学参数

为了解十氢十硼酸双四乙基铵(BHN-10)热分解特性及反应动力学,采用同步热分析-红外质谱联用技术(TG-DSC-MS-FTIR)及热裂解原位池-傅里叶变换红外光谱联用技术(FTIR)对BHN-10热分解过程中间产物和最终产物进行分析;使用Kissinger和Ozawa方法计算两个热分解阶段的动力学参数,并利用Coats-Redfern法拟合得到反应动力学方程。结果表明,BHN-10热分解第一阶段和第二阶段的活化能分别为150.9 kJ/mol和161.7 kJ/mol;第一阶段受随机成核和核增长机理控制,第二阶段遵从幂级数法则(Mampel power);两阶段的动力学机理函数分别为G(α)=[-ln(1-α)]1/3(n=3)和G(α)=α1/4;BHN-10热分解反应第一阶段质量损失2.9%,与理论脱氢质量损失相一致,此阶段发生B10H2-10的脱氢产生氢气和非晶态硼的过程,在热分解第一阶段会生成熔融分解型的中间产物四乙基铵阳离子;第二步反应质量损失39.4%,接近第二阶段气体质量损失的计算值43.4%,是四乙基铵阳离子上的质子转移并通过Hoffman消除反应生成乙烯和Et3N,Et3N进一步分解为C 2H 6、NH3、H2和碳单质。     

化合物[NH_3CH_2CH_2NH_3][CuCl_4]的热稳定性及其分解动力学研究

利用液相法合成了[NH3CH2CH2NH3][CuCl4],并对化合物的热稳定性、热分解及其动力学进行了研究。采用TG-DTG技术研究化合物[NH3CH2CH2NH3][CuCl4]的热分解,并应用微分法（Achar法）、Coast-Redfern法、Kissinger法、Ozawa法对非等温动力学数据进行处理,发现晶体的第一步分解是二维扩散反应,n=2,机理函数积分形式g（α）=[1-（1-α）1/2]2和微分形式f（α）=（1-α）1/2[1-（1-α）1/2]-1,表观活化能Ea=192.56 kJ.mol-1,指前因子A=2.13×1016s-1。标题化合物的第二步分解是化学反应,机理函数积分形式g（α）=（1-α）-1-1和微分形式f（α）=（1-α）2,表观活化能Ea=164.70 kJ.mol-1,指前因子A=2.90×1012s-1。     

Decomposition of Mullite

Free surfaces of 2:1 mullite (2Al₂O₃·SiO₂) specimens decomposed with the evolution of SiO and O₂ when they were heated at high temperatures under low partial pressures of O₂; this reaction was analyzed thermodynamically. In addition, bubbles were observed at internal interfaces between mullite and fused-SiO₂ diffusion couples. These bubbles, when formed at 1 atm ambient pressure between 1650° and 1800°C, resulted from reaction of Si particles and residual SiO₂-rich glass in the fused cast mullite.     

DL-2-萘普生热分解过程和非等温热分解动力学研究

用热重-差热联用分析(DTA-TGA)技术和差动扫描(DSC)技术研究了DL-2-萘普生在空气中的热分解过程和非等温热分解机理及动力学.DTA-TGA分析表明DL-2-萘普生在((250.722～296.87)±4.88)℃之间发生热分解反应,结合DSC分析表明DL-2-萘普生的熔点为(158.16±0.6)℃,熔融热...     

Thermal Decomposition of Brucite: II, Kinetics of Decomposition in Vacuum

Polycrystalline samples, thin single crystals, and—325 mesh powders of brucite decomposed according to a first-order rate equation consistent with a random nucleation process in beds of micron-sized particles formed by disruption during the very early stages of the process and consistent with electron and optical microscope observations. Kinetic data for the decomposition of thick single crystals were more complex but could be fitted to an interface-model equation which predicts that decomposition will be controlled by the movement of an interface reaction along the basal plane. Physical disruption of these crystals was confined initially to the outer edges of the crystals and proceeded along the basal plane in the form of a contracting disk. Since the decomposition occurs in cracked material and not at a strict interface, the fit of the data to the interface model may be fortuitous.     

Decomposition Chemistry of Tetraethoxysilane

SiO₂ films deposited by the decomposition of tetraethoxysilane (TEOS) at high temperatures have superior insulating properties and excellent step coverage, but are not compatible with aluminum metallization. Earlier work on the deposition of SiO₂ from TEOS concentrated on the properties of the film and on the modeling of thickness uniformity, but no attempt was made to probe the decomposition chemistry. In the present work a three-step model is presented to explain the TEOS deposition chemistry. A useful deposition temperature is determined by the first step where an intermediate is formed in the gas phase. This activated species adsorbs on the surface and later decomposes into SiO₂. Equilibrium constants for the gas-phase intermediate formation and surface adsorption respectively are 1.38 × 10¹⁰ exp[(– 299.24 kJ/mol)/ RT ] and 1.14 × 10⁴ exp[(– 21.80 kJ/mol)/ RT ]. The rate constant for the surface decomposition of the intermediate is 1.29 × 10⁻⁶ exp[(– 12.26 kJ/mol)/ RT ]. This model successfully explains rate dependence on pressure and temperature. Approaches are suggested which would catalyze the formation of the activated species and thus lower the deposition temperature such that this process could be used instead of aluminum metallization.     

Decomposition of burning polytetrafluoroethylene

PTFE rods, 0.6–3.8 cm diameter, were burnt from the top downwards in a gently rising atmosphere of oxygen. The burning was only possible in concentrated oxygen, or at elevated temperature or pressure. At its surface temperature of 920 ± 25°K, the polymer evolved monomeric C₂F₄ which oxidized in a surrounding gas flame; 15–35% of all the carbon in the gas was found present as monomer just above the larger rods. Depolymerization of the solid was not its only mode of decomposition, however. The heat radiated and conducted from the flame into the condensed phase was too little to depolymerize it completely, and heterogeneous reactions with species from the gas phase must also have contributed to the decomposition. Overall, the polymer burnt in O₂, but the gaseous reactant which attacked the surface need not have been O₂ or O in all cases, for these rare species just above the larger rods. Elemental fluorine was present in the gas even when elemental oxygen was absent, and calculations indicate that F atoms would be a major flame species at equilibrium. It is possible that heterogeneous attack by flame generated F atoms consumed part of the polymer and also supplied energy to help depolymerize the rest.     

Thermal Decomposition of Sodalites

The decomposition of bromate and hydroxide sodalites was studied by DTA and TG. Bromate sodalite is converted exothermally at 600°C into bromide sodalite. Hydroxide sodalite loses water and is then converted endothermally into a carnegieite phase at 740°C. The conversion of hydroxide sodalite mixed with sodium halide into halide sodalite at temperatures >740°C proceeds via the decomposition of the hydroxide sodalite. After hydroxide sodalite is heated to temperatures between 600°C and the conversion temperature, it exhibits the photoluminescence of O₂⁻.     

Decomposition Chemistry of TAGN

Triaminoguanidine nitrate (TAGN) is a unique energetic material which produces relatively low molecular weight combustion products. TAGN is characterized by the oxidizer fragment “HNO₃” that is attached by an ionic bond in the molecular structure. In this study, various types of experiments were conducted in order to elucidate the physicochemical decomposition process of TAGN. The exothermic rapid reaction observed at the early stage of the decomposition is the process representing the nature of energetics of TAGN. This exothermic reaction occurs immediately after the endothermic phase change from solid to liquid. Since the weakest chemical bond consisting in the TAGN molecule is the N N bond (159 kJ/mol), the initial bond breakage should be the amino groups and the NH₂ radicals split off. The energy released by the dissociation of the NH₂ radicals (104.3 kJ/mol) is the heat produced at the early stage decomposition of TAGN. Thus, the burning rate of TAGN is considered to be dominated by the dissociation of the NH₂ radicals. It must be noted that the burning rate of TAGN is almost double that of HMX even though the energy contained in the unit mass of TAGN is less than that of HMX. The HNO₃ attached to the molecular structure of TAGN is not the fragment to produce the exothermic rapid reaction observed at the early stage decomposition process.     

Thermal Decomposition of Aminonitrobenzodifuroxan

In this study, the thermal decomposition properties of aminonitrobenzodifuroxan are studied using a differential scanning calorimeter (DSC), a thermogravimeter (TG), an X‐ray diffractometer, a mass spectrometer (MS), and a Fourier transform infrared spectrometer (FTIR). The results demonstrate that aminonitrobenzodifuroxan undergoes thermal decomposition in the solid state. Under elevated temperatures, the decomposition primarily involves two steps: separation of nitro group and ring‐scission of the furoxan circles at 198.1 °C, and decomposition of the relatively stable residues (benzofuroxan circle) at 199.1 °C. Moreover, it is found that among the products, nitrogen dioxide undergoes oxidation and catalysis on the host molecule during the whole decomposition. Based on Kissinger and Ozawa functions, we deduce that the activation energies of these two reactions are 167.68 and 204.55 kJ mol⁻¹, respectively. The released energy (ΔH) of CL‐18 is −1781.8 J g⁻¹.     

The Thermal Decomposition of Isocyanurates

The thermal decomposition of two isocyanurates and an MDI-based polycarbodiimide was studied by high temperature infrared spectroscopy, thermogravimetric analysis and differential thermal analysis. The results (confirmed by large scale pyrolysis) show that the s-triazine moiety decomposes above 400°C to generate free isocyanate groups. The latter may react further to give carbodiimides or ureas.     

地震道子波分解

根据时频分析的思想,引入全新时频分析方法——子渡分解。子波分解可将地震道分解成不同主频、不同时间的子波集合,从而实现地震道在时、频率域内的精确分解。分解后的子波可以按特定频率和时间深度重构出多种地震道。采用树型模型对地震道实现子渡分解,全子波重构道与原始地震道的一致性验证了分解方法的正确性。