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含能材料 2015年第12期23卷 1186-1191页

作者： Svatopluk Zeman Marcela JUNGOV qi-long yan Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of Pardubice

The relationship between the crystal lattice free volume,ΔV,and impact sensitivity,E_(dr),of ten nitramines has been analyzed. It was found that this relationship is not uniquely determined,i. e. it is not given only by their own ΔV values but fundamentally by the type and intensity of the intermolecular forces in the nitramine crystals. Also,relationships between the E_(dr)values,on the one hand,and bulk modulus,K,and shear modulus,G,on the other,have been the subject of discussion not only for pure cyclic nitramines but also for their PBXs,bonded by a poly-fluoro binder. The closest linear correlation exists between the E_(dr)values and dimensionless K·G^(-1) ratio which indicates the plasticity range. A similar relationship is valid also for the ΔV values. Relationships of the E_(dr) and / or ΔV values with the shear modulus or to the K·G^(-1) ratio reflect an unusual behavior of ε-HNIW to which the published morphological instability of this particular HNIW version might also be related.

关键词：爆破器料含能材料烟火器材材料学

Anti-sintering behavior and combustion process of aluminum nano particles coated with PTFE:A molecular dynamics study

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Defence Technology（防务技术） 2023年第6期24卷 46-57页

作者： Jun-peng Liu Hao-rui Zhang qi-long yan Science and Technology on Combustion Internal Flow and Thermostructure LaboratoryNorthwestern Polytechnical UniversityXi'an 710071China

The characteristic of easy sintering of aluminum nanoparticle(ANP)limits its application in solid *** ANP with fluoropolymer could effectively improve its combustion *** find out how the coating layer inhibits sintering and promotes complete combustion of particles from an atomic view,a comparative study has been done for bare ANP and PTFE coated ANP by using reactive molecular dynamics *** sintering process is quantified by shrinkage ratio and gyration *** results show that,at the same heating rate and combustion temperatures,bare ANPs are sintered together after the temperature exceeds the melting point of aluminum but the decomposition of PTFE coating layer pushes particles away and increases reaction surface area by producing small Al-F *** sintering of ANPs which are heated in PTFE is alleviated compared with particles heated in oxygen,but particles still sinter together due to the lack of intimate contact between PTFE and alumina *** effect of temperature on the combustion of PTFE coated ANPs is also studied from 1000 to3500 *** number density analysis shows the particles will not be sintered at any *** fluoride prefers diffusing to the external space and the remained particles are mainly composed of Al,C and *** ignition simulations are performed by adopting micro canonical *** the expansion of aluminum core and the melting of alumina shell,bare ANPs are sintered into a liquid particle *** PTFE coated ANPs,the volatilization of gaseous aluminum fluoride products continually endows particles opposite momentum.

关键词： Aluminum nanoparticle Sintering Combustion Molecular dynamics simulation

Comparison with Molecular Surface Electrostatic Potential and Thermal Reactivity of Nitramines

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含能材料 2015年第12期23卷 1155-1161页

作者： Svatopluk Zeman Zdenek Friedl Monika Bartoskova qi-long yan Institute of Energetic Materials Faculty of Chemical TechnologyUniversityo f PardubiceCZ-53210PardubicetheCzechRepublic Facultyof Chemistry Brno Universityof TechnologyCZ.-61200Brnothe Czech Republic

Molecular surface electrostatic potentials V_S(r) ( ESP) of seventeen nitramines have been calculated. As a criterion of the imbalance between the maximum positive,V_(S,max) and minimum negative,V_(S,min),values of molecular surface electrostatic potentials their sum was derived and used as a new simple characteristic for ESPs-V_(S,Σ). These V_(S,Σ) values have close relationships with the Arrhenius parameters,activation energy E_a and preexponent log A,of thermal decomposition of the nitramines studied. The correlation between the V_(S,Σ) values and heats of fusion of the nitramines studied is described. These findings suggested analyzing the physico-chemical behavior of the nitramine crystals during this decomposition; in this connection an investigation was carried out using isothermal thermogravimetry and scanning electron microscopy of thermally exposed crystals of cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5-d]imidazole( sintering of its crystal surfaces),of β-1,3,5,7-tetranitro-1,3,5,7-tetrazocane( cracking of its crystals during β !δ transition) and of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane. The results suggest a need to study the pre-decomposition states on thermal decomposition of the nitramines' molecule's crystals.

关键词：爆破器料含能材料材料烟火材料

Tuning the reactivity of Al-Ni by fine coating of halogen-containing energetic composites

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Defence Technology（防务技术） 2022年第10期18卷 1810-1821页

作者： Su-lan yang Ke-juan Meng Wu-xi Xie Hong-qi Nie qi-long yan Science and Technology on Combustion Internal Flow and Thermo-Structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China b Xi'an Modern Chemistry Research Institute Xi'an710065China

In this paper,various core-shell structured Al—Ni@ECs composites have been prepared by a spray-drying *** involved ECs refer to the energetic composites(ECs)of ammonium perchlorate/nitrocellulose(AP/NC,NA)and polyvinylidene fluoride/hexanitrohexaazaisowurtzitane(PVDF/CL-20,PC).Two Al—Ni mixtures were prepared at atomic ratios of 1:1 and 1:3 and named as Al/Ni and Al/3Ni,*** thermal reactivity and combustion behaviors of Al—Ni@ECs composites have been comprehensively *** showed that the reactivity and combustion performance of Al—Ni could be enhanced by introducing both NA and PC energetic *** which the Al/Ni@NA composite exhibited higher reactivity and improved combustion *** measured flame propagation rate(v=20.6 mm/s),average combustion wave temperature(T_(max)=1567.0°C)and maximum temperature rise rate(γ_(t)=1633.6°C/s)of Al/Ni@NA are higher than that of the Al/Ni(v=15.8 mm/s,T_(max)=858.0°C,andγ_(t)=143.5°C/s).The enhancement in combustion properties could be due to presence of the acidic gaseous products from ECs,which could etch the Al_(2)O_(3)shell on the surface of Al particles,and make the inner active Al to be easier transported,so that an intimate and faster intermetallic reaction between Al and Ni would be ***,the morphologies and chemical compositions of the condensed combustion products(CCPs)of Al—Ni@ECs composites were found to be different depending on the types of *** compositions of CCPs are dominated with the Al—Ni intermetallics,combining with a trace amount of Al_(5)O_(6)N and Al_(2)O_(3).

关键词： Arrested high energy ball milling Intermetallic alloy Combustion performance Energetic composites Reactivity control

Fabrication and characterization of multi-scale coated boron powders with improved combustion performance:A brief review

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Defence Technology（防务技术） 2024年第1期31卷 27-40页

作者： Rui Liu Danfeng yang Kunyu Xiong Ying-Lei Wang qi-long yan Science and Technology on Combustion Internal Flow and Thermo-structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China Xi'an Modern Chemistry Research Institute Xi'an710065China

Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion *** literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal *** techniques include recrystallization,dual-solvent,phase transfer,electrospinning,*** one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron *** comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed *** and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature.

关键词： Boron powder coating Structure and morphology Condensed phase thermal reaction Ignition and combustion

Crystal lattice free volume in a study of initiation reactivity of nitramines:Friction sensitivity

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Defence Technology（防务技术） 2018年第2期14卷 132-136页

作者： Svatopluk Zeman Ning Liu Marcela Jungová Ahmed K.Hussein qi-long yan Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceCZ-532 10PardubiceCzech Republic Xi'an Modern Chemistry Research Institute Xi'anShaanxi710065China School of Astronautics Northwestern Polytechnical UniversityXi'an 710072ShaanxiChina

The relationship between friction sensitivity(FS) and the crystal lattice free space per molecule, △V. of thirteen nitramines is described by a linear equation, divided into a number of the partial relationships with strong limitations by their molecular structure characteristics. Increasing FS due to raising of the △V values is not clearly confirmed. The influence of the △V values on friction sensitivity of nitramines is similar to that of their aza atoms which influence the mutual orientations of nitro groups in neighboring molecules. The dipole-dipole interaction of the oxygen and nitrogen atoms of nitro groups in neighboring nitramine molecules has a major effect on their own FS. In accordance with this interaction, a directly proportional relationship was derived between FS and the intrinsic gas phase molecular volume, V_(int), of the nitramines mentioned, which is divided also into several straight lines according to relatively tight molecular structure similarity. The relationships found again confirm a level of disorder in the distribution of the forces in the crystal lattice of the "common" quality of ε-2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane, in comparison with its reduced sensitivity(RS) or chemically pure analogue.

关键词： Crystal lattice Friction Initiation reactivity Nitramines

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一种半主动激光红外雷达三模复合光学系统设计

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红外技术 2015年第7期37卷 588-592页

作者：齐雁龙项建胜中国空空导弹研究院河南洛阳471009

介绍了一种紧凑型的半主动激光、红外、雷达三模复合光学系统,半主动激光、红外光学系统采用折反式光路结构,雷达系统采用抛物面天线发射接收信号。3种导引模式共用一个主反射镜,半主动激光系统与红外系统在主反射镜处光线分离,雷达波... 详细信息

介绍了一种紧凑型的半主动激光、红外、雷达三模复合光学系统,半主动激光、红外光学系统采用折反式光路结构,雷达系统采用抛物面天线发射接收信号。3种导引模式共用一个主反射镜,半主动激光系统与红外系统在主反射镜处光线分离,雷达波与红外光在主反射镜共口径反射后,在次反射镜处信号分离,在紧凑空间内实现了3种导引模式的融合。

关键词：折反系统抛物面天线半主动激光复合导引光学系统

Enhancing the Combustion Performance of Metastable Al@AP/PVDF Nanocomposites by Doping with Graphene Oxide

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Engineering 2020年第9期6卷 1151-1160页

作者： Shuwen Chen De-Yun Tang Xue-Xue Zhang Jie-Yao Lyu Wei He Peijin Liu qi-long yan Science and Technology on Combustion Internal Flow and Thermostructure LaboratoryNorthwestern Polytechnical UniversityXi'an 710072China

利用喷雾造粒技术制备了一类新型的亚稳态分子间复合含能材料(metastable intermixed composite,MIC)。这种复合材料由铝(Al)、高氯酸铵(ammonium perchlorate, AP)和聚偏氟乙烯(polyvinylidene fluoride, PVDF)组成,其中Al作为燃料,AP和PVDF共同作为氧化剂,并根据最大反应放热量确定AP和PVDF的添加比例。此外,在材料中还掺杂了少量的氧化石墨烯(graphene oxide, GO)充当润滑剂和催化剂。结果表明,含有0.2%氧化石墨烯的Al@AP/PVDF具有最大的密度(2.57 g·cm^-3)和最高的反应放热量(5999.5 J·g^-1)。这些值远高于Al@AP/PVDF的密度(2.00 g·cm^-3)和反应放热量(5569.8 J·g^-1)。氧化石墨烯的加入提高了Al@AP/PVDF的反应速率并改善了其热稳定性。掺杂0.2%氧化石墨烯的Al@AP/PVDF使得火焰传播速率达到了4.76 m·s^-1,相对于Al@AP/PVDF的火焰传播速率提高了约10.7%。掺杂氧化石墨烯的Al@AP/PVDF(Al@AP/PVDF-GO)具有更好的界面接触和颗粒分散性,从而提高了传热速率,消除了纳米铝(nano-Al)粉微粒的团聚现象,提高了燃烧反应速率。本研究使得铝基MIC的能量释放和燃烧效率得到了提高。

关键词：亚稳态分子间复合材料 Al@AP/PVDF纳米复合材料氧化石墨烯能量释放燃烧性能

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li Ting Zhang yanlin Fu Peiyan long Xiao Gao Zhengwei Wang Zhizhong Guan Xiaolan qi Wei Hong yan Xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

填料塔气体分布器二相流场计算流体力学数值模拟

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化学工程 2008年第7期36卷 24-27页

作者：刘德新李鑫钢徐世民齐延龙天津大学化工学院吉林吉林132002 天津大学中国石油吉化集团公司吉林吉林132002

填料塔内气体分布器对进料气流的分布作用和填料塔的分离效率,特别是对低压降、高效填料有重大影响。文中运用计算流体力学(简称CFD),采用欧拉-拉格朗日二相流模型建立了填料塔内双切向气体分布器内三维瞬态气液二相流模型,气体的湍流... 详细信息

填料塔内气体分布器对进料气流的分布作用和填料塔的分离效率,特别是对低压降、高效填料有重大影响。文中运用计算流体力学(简称CFD),采用欧拉-拉格朗日二相流模型建立了填料塔内双切向气体分布器内三维瞬态气液二相流模型,气体的湍流运动采用k-ε湍流模型计算。模型中考虑了二相之间的作用力,包括液滴所受的曳力和虚拟质量力。求解时时间项采用隐式格式,时间步长取1×10-4s,对流项采用二阶迎风格式,压力-速度耦合方程的求解采用了S imp lec方法。在不同操作条件下,模型计算得到的压降、夹带、气体分布不均匀度和文献报道的实验值吻合较好。从而可以看出,CFD模型可以较为准确地描述双切向环流式气体分布器内瞬时气液二相流场。

关键词：气体分布器计算流体力学气液二相流模型