Chemical Kinetic Modeling of HMX and TATB Laser Ignition Tests

Recent high-power laser deposition experiments on octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) produced ignition times from milliseconds to seconds. Global chemical kinetic thermal decomposition models for HMX and TATB developed to predict thermal explosion experiments lasting seconds to days are applied to these laser ignition experimental data. Excellent agreement was obtained for TATB, while the calculated ignition times were longer than experiment for HMX at lower laser fluxes. Inclusion of HMX melting and faster reaction for liquid HMX in the HMX decomposition model improved the agreement with experiment at lower laser energies.     

Crystal State of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB) Undergoing Thermal Cycling Process

The present report aims to discuss the crystal state variation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) suffering from thermal cycling process. In this study, in situ X-ray powder diffraction (XRD) was employed to determine thermal expansion and crystal fragmentation, primarily attributed to its crystal state variation. The results showed that the change of crystal volume mainly stemmed from the thermal expansion at the c axis of crystal lattice, and TATB crystal had the same thermal expansion coefficients at a and b axes. It was also demonstrated that crystal fragmentation occurred during this process, and more auto-repair happened in the [002 Giefers , H. , M. Pravica , W. Yang , and P. Liermann . 2008 . Radiation-induced decomposition of explosives under extreme conditions . Journal of Physics and Chemistry of Solids , 69 : 2208 – 2212 . [Google Scholar]] plane of TATB than other planes. These results will have an implication on the process of TATB-based materials.     

Comparison of asphaltene structure and morphology under different deasphaltene methods

Problems associated with asphaltene deposition during the production, transportation, and processing of crude oils are some of the important issues in oil industry. Thus, accurate identification of structure and surface morphology of asphaltene should be investigated. In this study, asphaltene are isolated from an Iranian heavy crude oil under three different experimental conditions by using heat (thermal deasphaltene), heat and toluene (thermal-toluene deasphaltene), and n-heptane (n-heptane deasphaltene) as precipitation agent. The effect of isolation method on the crystallite structure and surface morphology of asphaltene is characterized by X-ray diffraction and scanning electron microscope technique, respectively. It is found that extraction procedure has a strong influence on the physicochemical properties of the isolated asphaltene. The results showed that at thermal deasphaltene solid such as micellar the shape was the dominant morphology of asphaltene particles that cause the least height of the crystallites and number of aromatic sheets in a stacked cluster. This morphology changes to semisolid smooth surface and agglomerated asphaltene with cavities by altering the separation method to thermal-toluene deasphaltene and n-heptane deasphaltene. The maximum heights of the crystallites belong to n-heptane deasphaltene.     

排水沥青混合料高温稳定性能的研究

通过选择不同集料级配和不同沥青用量，分析研究了排水沥青混合料的高温稳定性能，得到了相应的关系，并进一步研究了动稳定度和马歇尔稳定度之间的相互关系，为排水沥青混合料的配合比设计和物理力学性能分析提供了参考。     

Effect of Different Aromatic Fractions on Colloidal Property of Tahe Atmospheric Residue

Different amounts of FCC slurry oil and HVGO were added to Tahe atmospheric residue respectively.The colloidal stability and asphaltene agglomeration of atmospheric residue and mixed oils were characterized by means of the mass fraction normalized conductivity and the small-angle X-ray scattering technology(SAXS).The results indicated that the stability of Tahe atmospheric residue decreased with an increasing amount of these oil fractions.It was found that the decline of the colloidal stability was attributed to the component polarity difference between oil fractions and the atmospheric residue.Though the aromaticity of FCC slurry oil was higher than that of HVGO,the polarity of aromatics and resins of FCC slurry oil was lower than those of HVGO.So the degree of the colloidal stability was more seriously destroyed by FCC slurry oil.The dispersion of asphaltenes in Tahe atmospheric residue was changed by adding FCC slurry oil and HVGO.The particle size of asphaltenes increased along with the decline of the colloidal stability.     

一种新型高效有机钼添加剂

在ＳＲＶ长磨试验机和四球试验机上考察、评定了新型烷基芳胺基二硫代磷酸硫化氧钼（简称ＭｏＡＤＴＰ）的摩擦学性能。结果表明，ＭｏＡＤＴＰ较现有技术的有机钼抗氧化性和高温承载能力有了大的提高，并具有优良的防腐和清净分散性能，是一种较为理想的高效多功能有机钼润滑油添加剂。     

Quantum-Chemical Studies on TATB Processes

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.     

多孔玄武岩沥青混合料的设计与分析

多孔玄武岩其吸水率较大，同样吸收沥青也较大，从而对混合料配合比设计、质量控制和使用性能都产生很大的影响。采用马歇尔法和SUPERPAVE旋转压实仪法对罗孔玄武岩进行设计，两种方法设计的最佳沥青含量、混合料理论最大相对密度和矿料间隙率均差别较大。采用马歇尔法对混合料进行设计和现场控制时，应参照SUPERPAVE的设计数据。     

Theoretical Investigation of Pyridine Derivatives as High Energy Materials

In this work, properties of polynitro-bridged pyridine derivatives were systemically studied at the B3LYP/6-31G(d) level. Gas-phase heats of formation (HOFs) for the designed compounds were calculated using isodesmic reactions, and their solid-phase HOFs were estimated using the Politzer approach. All designed compounds possess large solid-phase HOFs, larger than 700 kJ/mol. Based on the predicted crystal densities, solid-phase HOFs, and chemical energies, detonation properties were evaluated by means of Kamlet-Jacobs empirical equations. The results show that detonation velocities and pressures of all of the designed compounds are above 9.30 km/s and 40.00 GPa, respectively. In addition, bond dissociation energy (BDE) was employed to investigate their thermal stability. Considering solid-phase HOFs, detonation performance, and thermal stability, most of the designed compounds meet the requirements of high energy density materials (HEDMs).     

新型耐温耐盐表面活性剂驱油体系的研究

合成了一种聚氧乙烯醚磺酸盐型表面活性剂，并将其与廉价的渣油磺酸盐表面活性剂复配，得到一种耐温、耐盐的复配表面活性剂驱油体系。将该表面活性剂驱油体系用于大港油田原油，在85℃下、模拟水的矿化度为35337mg／L、高价离子(Ca^2 、Mg^2 )含量为1000mg／L时，油水界面张力仍可达到超低(约10^-3mN／m)，能满足大港油田部分高温、高矿化度油藏对驱油用表面活性剂的要求。     

高温高压储层安全钻井液密度窗口确定技术

井壁温度变化和井壁渗流对高温高压储层安全钻井液密度窗口的影响不容忽视,而确定钻井时安全钻井液密度窗口的常规方法中没有考虑井壁温度变化及井壁渗流的影响,为安全钻井带来了隐患。为此,依据孔隙热弹性小变形应力叠加原理,从附加温变应力场以及附加渗流应力场作用下井周应力场计算出发,结合地层的强度准则,建立了综合考虑井壁温度变化及井壁渗流情况下高温高压储层坍塌压力、破裂压力的计算模型,并分析了井壁温度变化及井壁渗流对安全钻井液密度窗口的影响规律。为高温高压储层安全钻井液密度窗口的设计提供了依据。     

A New Approach to Calculate the Mud Density for Wellbore Stability Using the Asymptotic Homogenization Theory

Abstract

This study addresses mud density prediction as part of wellbore stability analyses considering effective rock properties and using friction and elastic theories to determine the deviator stress at failure. The effective rock properties for different sandstone porosities were obtained through the theory of asymptotic homogenization, and the wall vicinity stresses at the borehole wall were estimated considering friction and elastic theories. The use of the method of asymptotic homogenization (MHA) allows obtaining effective rock mechanical properties varying in porosity and saturation conditions.     

复合添加剂对环丁砜热稳定性的影响

考察了单乙醇胺与碱性添加剂H,N-M,2-t-B复配前后对环丁砜热稳定性的影响,以SO2的释放量作为环丁砜热稳定性的评价指标。实验结果表明,在环丁砜用量100 g、氮气流量80 mL/min、反应温度230℃、反应时间2 h的条件下,当单乙醇胺用量为环丁砜质量的0.04%时,SO2释放量最少,为16.48 mg,抑制环丁砜受热分解的效果最好。当单乙醇胺与碱性添加剂复配后,复合添加剂抑制环丁砜受热分解的效果优于单独添加单乙醇胺的效果;4种添加剂对环丁砜热稳定性的影响由大到小的顺序为:单乙醇胺>H>N-M>2-t-B。将4种添加剂复配,当单乙醇胺、H、2-t-B、N-M的用量分别为环丁砜质量的0.03%,0.06%,0.10%,0.06%时,复合添加剂对环丁砜热分解的抑制效果最佳,SO2释放量最少,为5.49 mg。     

高温高黏胶凝酸PDA合成及性能评价

以碳酸岩油藏的高温、深井的酸化增产为切入点,从提高胶凝酸液体系抗温性、配伍性和溶解性以及减少地层伤害等实际应用性能出发,采用阳离子单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)、丙烯酰胺(AM)为原料,合成了新型酸液胶凝剂PDA。室内实验表明新型胶凝剂PDA具有良好的热稳定性和剪切稳定性,缓速性能好,将通常酸液体系中聚合物胶凝剂含量从2.5%降到1.0%,大大减少了聚合物的用量,从而减小了酸化过程中聚合物残渣对储层造成的潜在伤害,具有较好的开发前景。     

埃洛石纳米硅铝管(HNTs)的结构和物理性能

运用SAXS、XRD、TEM、BET、TGA、FT-IR和NH₃-TPD表征手段深入研究了中国产的埃洛石纳米硅铝管(HNTs)的结构和物理性能。分别考察了焙烧温度和酸碱水热处理对HNTs纳米管结构的影响,研究了HNTs纳米管材料的质量损失和酸性位性质。结果表明,采用小角度散射表征(SAXS)计算的HNTs纳米管的孔径与TEM表征基本一致,孔径约为20~30 nm; HNTs具有良好的热稳定性和较好的耐酸碱性;在400~550℃温度范围内,HNTs失去羟基缩合产生的化学水; HNTs既具有中强酸性位又具有强酸性位。     

Novel high-energy ionic molecules deriving from new monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties

ABSTRACT

In recent years, the exploration of a practical strategy for novel energetic molecules with high energy and low sensitivity is very desirable but highly challenging. Novel ionic energetic molecules have attracted much attention in this area due to their prominent advantages including low sensitivities, high thermal stability, and excellent energy performances. Herein, five different ionic energetic molecules based on new monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties with enhanced oxygen balance have been synthesized, characterized and evaluated as potential high-energy materials. Thermal stability, sensitivities and energy output test were measured and studied in detail. The heats of formation and energetic parameters were calculated by using Gaussian 09 suite of programs and EXPLO 5 code. The results suggest that all as-prepared new molecules exhibit good thermal stability with high decomposition temperature (3, 231°C; 5, 160°C; 6, 185°C; 7, 180°C; 8, 213°C), and relative low sensitivity (IS > 20 J, FS = 324 N). Inheriting the significant oxygen content of monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties, they also possess good energy properties (v _D = 8238 ~ 9208 m s^?1, P = 26.8 ~ 36.7 GPa, V _o = 481.8 ~ 959.4 L kg^?1), which make them competitive high-energy materials.     

Further insights into the discoloration of TATB under ionizing radiation

ABSTRACT

To determine degradation products formed by exposure of TATB to ionizing radiation, a computational and experimental study is presented. Thermochemical and spectral data have been calculated using DFT at the MH06-HF/aug-cc-pVTZ level which suggest the formation of the cation radical derivative of TATB. Irradiated TATB samples showed the widely reported yellow-to-green discoloration, with measured CIE L*, a*, b* and RGB values correlating with total dose. Trace quantities of a mono-furazan derivative were detected by HPLC-MS; the discoloration is not attributed to this, but rather to the presence of a paramagnetic species (i.e., the cation), as detected by ESR measurements. Recrystallized irradiated TATB samples reverted to their original color, further suggesting it is the cation radical that is responsible for color change.     

埃洛石对聚丙烯树脂热稳定性及热氧老化行为的影响

以埃洛石(HNT)掺杂的高效Mg Cl2/Ti Cl4为催化剂催化丙烯聚合,制备了含HNT的聚丙烯(PP-HNT)树脂。采用TG分析法研究了PP-HNT树脂的热稳定性,并用DSC法考察了PP-HNT树脂的热氧老化性质。热稳定性实验结果表明,HNT的添加显著提高了PP-HNT树脂的热稳定性;在氮气气氛下,PP-HNT树脂的热分解温度与纯PP树脂相比大幅提高,含168×10-6(w)HNT的PP-HNT树脂的热分解温度达到456℃,与纯PP树脂的热分解温度相比,提高了52℃;在空气气氛下,HNT的存在使PP的热分解速率明显变慢。热氧老化实验结果表明,含量为10-6(w)级的HNT的添加未恶化PP的热氧老化性质,未缩短PP的氧化诱导时间,同时在HNT含量一定的条件下进一步降低了PP的氧化速率。     

新戊基多元醇酯结构与热稳定性的关系

用热失重法考察了新戊基多元醇酯结构与热稳定性的关系。长链脂肪酸和长链异构脂肪酸可以提高新戊基多元醇酯的热稳定性,而短链的异构酸则会降低新戊基多元醇酯的热稳定性。新戊基多元醇酯的热稳定性随羟基的增加而提高。     

航空生物燃料热稳定性研究

航空生物燃料作为环境友好的可替代燃料应用于民用航空器上应满足适航标准的要求。航空燃料的热氧化稳定性是航空油料质量控制的重要指标,建立严格的质量控制体系对确保航空飞行安全有着重大意义。文章对航空生物燃料的热氧化机理、氧化稳定性影响因素生物燃料原料来源、储存条件及金属种类、含量及利用抗氧化剂改进其热稳定性的方法进行了综述,并对现有的航空生物燃料热氧化稳定性评价方法馏分加速氧化法、JFTOT方法、TGA方法进行了详细阐述。