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探针结构对Ti/CuO微波点火延迟时间的影响

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火炸药学报 2024年第5期47卷 468-474,I0006页

作者：唐魁赵团唐振华陈小远程用泷陈苏杭沈瑞琪徐抗震西北大学化工学院/西安市特种能源材料重点实验室陕西西安710069 陕西应用物理化学研究所陕西西安710061 南京理工大学化学化工学院/微纳含能器件工业和信息化部重点实验室江苏南京210094

为了研究探针结构对微波点火性能的影响,使用4种探针对Ti/CuO点火药的微波点火延迟时间进行了测试,并通过模拟对探针结构进行优化,获得了探针参数(长度、包覆层厚度、尖端锥度和镀层厚度)对电场强度的影响规律。结果表明,探针针尖处的... 详细信息

为了研究探针结构对微波点火性能的影响,使用4种探针对Ti/CuO点火药的微波点火延迟时间进行了测试,并通过模拟对探针结构进行优化,获得了探针参数(长度、包覆层厚度、尖端锥度和镀层厚度)对电场强度的影响规律。结果表明,探针针尖处的电场强度显著影响点火延迟时间,在2.45 GHz、50 W微波作用下,探针1、2、3、4最大电场分别为1800、190、34和53 kV/m,Ti/CuO的点火延迟时间分别为222.6、660.5、949.1和921.3 ms;在2.45 GHz、1 W微波作用下,当探针长度为26 mm、PTFE包覆层长度为8 mm、厚度为0.75 mm、针尖锥度为0.243和金镀层厚度为5μm时,能够将电场强度从原来的约10 kV/m提升到约1000 kV/m,并且电场分布集中于尖端。

关键词：微波点火探针点火药点火延迟时间电场强度点火器件

Synthesis and Crystal Structure of 4-(4,6-Dimethoxylpyrimidin-2-yl)-3-thiourea Carboxylic Acid Ethyl Ester

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Chinese Journal of Structural Chemistry 2008年第2期27卷 195-199页

作者： ZHANG Yang HUANG Jie SONG Ji-Rong REN Ying-Hui xu kang-zhen Department of Chemical Engineering Shaanxi Key Laboratory of Physico-inorganic Chemistry Northwest University Xi＇an 710069 China Conservation Technology Department the Palace Museum4 Jingshan Qianjie Beijing 100009 China

4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data： C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309（3）, b = 0.67682（6）, c = 1.74237（19） nm, β = 114.744（3）°, V= 2.7106（5） nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F（000） = 1200, Z= 8, R= 0.0514 and wR= 0.1529.

关键词： 4-(4,6-dimethoxyl-pyrimidin-2-yl)-3-thiourea carboxylic acid ethyl ester,synthesis crystal structure, ^-~ aromatic stacking interactions

Synthesis and Crystal Structure of 4-(4,6-dimethoxyl -pyrimidin-2-yl)-3-thiourea Carboxylic Acid Methyl Ester

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Chinese Journal of Structural Chemistry 2006年第2期25卷 168-172页

作者： HUANG Jie SONG Ji-Rong REN Ying-Hui xu kang-zhen MA Hai-Xia Department of Chemical Engineering Shanxi Key Laboratory of Physico-inorganic Chemistry Northwest Univers＇ity Xi＇an 710069 China

The title compound 4-（4,6-dimethoxylpyrimidin-2-yl）-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis＇ Crystallographic data： C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672（3）, b = 0.66383（12）, c = 1.1617（2） nm, β = 109.275（2）°, V = 1.2136（4） nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F（000） = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042.

关键词： 4-(4,6-dimethoxylpyrimidin-2-yl)-3-thiourea carboxylic acid methyl ester synthesis X-ray diffraction

Non-isothermal Decomposition Kinetics of K(AHDNE)

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Chemical Research in Chinese Universities 2012年第5期28卷 878-881页

作者： LU Lei xu kang-zhen QIU Qian-qian WANG Gang SONG Ji-rong ZHAO Feng-qi College of Chemistry and Chemical Engineering Yan'an UniversityYan'an 716000P.R.China School of Chemical Engineering Northwest UniversityXi'an 710069P.R.China Xi'an Modern Chemistry Research Institute Xi'an 710065P.R.China

The thermal behavior and non-isothermal decomposition kinetics of 1-amino-1-hydrazino-2,2-dinitro-ethylene potassium salt[K（AHDNE）] were studied under the non-isothermal conditions by different scanning calorimeter（DSC） method. The thermal behavior of K（AHDNE） presents three exothermic decomposition processes. The kinetic equation of the first thermal decomposition reaction obtained is dα/dT=（1019.63/β）3（1-α）[-ln（1-α）]2/3exp（-1.862× 105/RT）. The self-accelerating decomposition temperature（TSADT） and critical temperature of thermal explosion（Tb） of K（AHDNE） are 162.5 and 171.4 °C, respectively. K（AHDNE） has higher thermal stability than AHDNE.

关键词： 1-Amino-1-hydrazino-2 2-dinitroethylene(AHDNE) Potassium salt Non-isothermal decomposition kine- tics

Synthesis,Crystal Structure and Thermal Behavior of 4,5-Dimethoxy-2-(dinitromethylene)imidazolidine

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Chemical Research in Chinese Universities 2012年第4期28卷 716-720页

作者： WANG Min xu kang-zhen HE Fei ZHANG Hang CHEN Yong-shun SONG Ji-rong ZHAO Feng-qi School of Chemical Engineering Northwest UniversityXi'an 710069P.R.China The Palace Museum Beijing 100009P.R.China Science and Technology on Combustion and Explosion Laboratory Xi'an Modern Chemistry Research InstituteXi'an 710065P.R.China

A new energetic material,4,5-dimethoxy-2-（dinitromethylene）imidazolidine（DMDNI）,was synthesized by the reaction of 4,5-dihydroxyl-2-（dinitromethylene）-imidazolidine（DDNI） and methanol,and structurally characterized by single crystal X-ray *** crystallized in triclinic space group P1,with crystal data a=0.4324（4） nm,b=1.3599（11） nm,c=1.7503（14） nm,α=77.406（14）°,β=84.494（15）°,γ=87.976（14）°,V=0.9997（14） nm 3,Z=4,μ=0.140 mm-1,F（000）=488,D c =1.556 g/cm ^3,R 1 =0.0773 and wR 2 =*** decomposition of DMDNI was studied,and its thermal decomposition process was divided into two *** first stage was a melting process and the second stage was an exothermic decomposition *** enthalpy,apparent activation energy and pre-exponential constant of the exothermic decomposition reaction are-491.5 J/g,142.3 kJ/mol and 10 14.24 s^-1,*** critical temperature of thermal explosion is 162.47 °*** has a lower thermal stability than DDNI but it is close to that of 4,5-diacetoxyl-2-（dinitromethylene）-imidazolidine（DADNI）.

关键词： Crystal structure Thermal behavior 4 5-Dimethoxy-2-(dinitromethylene)imidazolidine(DMDNI) 1 1-Diamino-2 2-dinitroethylene(FOX-7)

Thermal Behavior, Specific Heat Capacity and Adiabatic Time-to-explosion of GDN

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Chemical Research in Chinese Universities 2009年第1期25卷 76-80页

作者： YANG Xing-kun xu kang-zhen ZHAO Feng-qi YANG Xin WANG Han SONG Ji-rong WANG Yao-yu College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 P. R. China Xi＇an Modern Chemistry Research Institute Xi＇an 710065 P. R. China Shaanxi Key Laboratory of Physico-inorganie Chemistry Northwest University Xi＇an 710069 P. R. China

A new compound, [（NH2）2C=NH2]＋N（NO2）2-（GDN）, was prepared by mixing ammonium dinitramide （ADN） and guanidine hydrochloride in water. The thermal behavior of GDN was studied under the non-isothermal conditions with DSC and TG/DTG methods. The apparent activation energy（E） and pre-exponential constant（A） of the exothermic decomposition stage of GDN were 118.75 kJ/mol and 10^10.86 s^-1, respectively. The critical temperature of the thermal explosion（Tb） of GDN was 164.09 ℃. The specific heat capacity of GDN was determined with the Micro-DSC method and the theoretical calculation method, and the standard molar specific heat capacity was 234.76 J·mol^-1·K^-1 at 298.15 K. The adiabatic time-to-explosion of GDN was also calculated to be a certain value between 404.80 and 454.95 s.

关键词： Guanidine dinitramide Ammonium dinitramide Thermal behavior Specific heat capacity Adiabatic time-to-explosion

Design Research of a Novel Aftercool-Humidifier Concept for Humid Air Turbine Cycle

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Journal of Thermal Science 2024年第3期33卷 951-969页

作者： ZHANG Junzheng xu zhen School of Energy and Power Engineering Shandong UniversityJi’nan250061China Shandong Engineering Laboratory for High-efficiency Energy Conservation and Energy Storage Technology&Equipment Shandong UniversityJi’nan250061China

Humid air turbine cycle(HAT)has potential of electrical efficiencies comparable to combined cycle,with lower investment cost and NO_(x) *** typical heat exchanger network of HAT consists of intercooler(if there is),aftercooler,recuperator,economizer and humidifier,which brings higher efficiency but makes the system more *** simplify HAT layout,a novel humidifier concept is proposed by integrating the aftercooler into traditional counter-current *** on this concept,a one-dimensional model including pressure drop and exergy calculation is established to distinguish the thermodynamic and hydrodynamic characteristics,and then the structural parameters,such as the number of rows and columns,tube diameter,pitch and type for a micro HAT are *** results show that the aftercool-humidifier plays the same role as original aftercooler and humidifier,and can match the in-tube air,out-tube air and water stream well with lower *** the case of micro HAT cycle,the volume of heat and mass transfer area can be reduced by 47%compared with traditional *** major thermal resistance occurred in the convection heat transfer process inside the tube;however,using enhanced tube cannot effectively improve the compactness of device.

关键词： humid air turbine cycle humidifier thermodynamic analysis one-dimensional model

Synthesis,Crystal Structure and Thermal Properties of Zn（NH3）3（AFT）2

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Chinese Journal of Structural Chemistry 2019年第7期38卷 1173-1181页

作者： MA Xiao DING Zi-Mei SHANG Fan HANG Xiao-Jing WANG Xiao-Hong xu kang-zhen HUANG Jie School of Chemical Engineering Northwest University/Shaanxi Key L aboratory of Physico-in organic Chemistry Xi 'an 710069 China Xi 'an Modern Chemistry Research Institute Xi 'an 710065 China

A new coordination compound of Zn(NH3)3(AFT)2(1,ZnC6H13N17O2,AFT =4-amino-3-(5-tetrazolate)-furazan)was synthesized and characterized by elemental analysis and FT-IR *** crystal structure was determined by X-ray single-crystal *** crystal belongs to the orthorhombic system,space group Pnma with a = 18.680(3),b = 6.9438(11),c =12.268(2)A,μ= 1.592 mm-1,V= 1591.3(4)A3,M,= 420.72,Dc=1.756 g·cm^-3,Z= 4,F(000)= 860,the final R = 0.0480 and wR = 0.1262 for the observed reflections with I>2σ(Ⅰ).The zinc(Ⅱ)ion is five-coordinated by N atoms from two AFT"ligands and three NH3 *** thermal decomposition mechanism of compound 1 was tested by differential scanning calorimetry(DSC)and thermogravimetry-derivative thermogravimetry(TG-DTG)*** DSC curve exhibits two endothermic and one exothermic *** addition,the non-isothermal kinetics parameters were calculated by using the Kissinger s method and Ozawa-Doyle's ***,the entropy of activation(ΔS≠),enthalpy of activation(ΔH≠),free energy of activation(ΔG≠)and impact sensitivity(IS)was also obtained.

关键词： 4-amino-3-(5-tetrazolate)-furazan synthesis crystal structure thermal behavior

Spatiotemporal variations in glacier area and surface velocity of the northern Antarctic Peninsula during 2018-2022

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Advances in Climate Change Research 2024年第2期15卷 297-311页

作者： Yu-Long kang Shi-Chang kang Wan-Qin GUO Tao CHE Zong-Li JIANG zhen-Feng WANG Qiang-Qiang xu Cheng-De YANG State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100083China Key Laboratory of Remote Sensing of Gansu Province Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Earth Sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China

Ice sheet serves as a crucial indicator for assessing climate *** loss in recent remote sensing-based studies indicated that the Antarctic Peninsula has rapid rates of glacier retreat and speed up of surface ***,observations of seasonal variability of ice speed are limited,and glacier-area changes require multi-temporal *** study investigated the changes in area and surface velocities of∼375 glaciers on the northern Antarctic Peninsula(NAP)utilizing satellite images acquired by the Sentinel 1&2 satellites during *** results indicate that the glacier area reduced by approximately 166.1±44.2 km^(2)(-0.2%±0.1%per year)during the study period,with an acceleration after 2020(-0.4%±0.3%per year),and the most dramatic reduction happened on the eastern *** maximum annual ice speeds on the NAP generally exceeded 3500 m per year,while the ice speeds in 2021 were the highest(exceeded 4210 m per year).The ice speed variability in austral autumn was higher than in other seasons,meanwhile the summer ice speeds showed an increasing *** glacier G012158E47018N,McNeile Glacier,glacier G299637E64094S and Drygalski Glacier showed the most remarkable ice speed variations represented by high daily velocities and strong fluctuations on their *** results demonstrated that the variations in glacier area and seasonal ice speed on the NAP were responsive to the ice-ocean-atmosphere ***,seasonal velocity and area variations should be considered when conducting accurate mass balance calculations,model validations and change mechanism analyses under climate warming scenarios.

关键词： Glacier area Seasonal ice speed Sentinel 1&2 Northern Antarctic Peninsula Ice-ocean-atmosphere processes