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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 Analysis of N-(2,3-Dimethyl-phenyl)-N'-(methoxyl formyl)thiourea

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Chemical Research in Chinese Universities 2012年第2期28卷 230-233页

作者： ZHAO Dan HUANG jie song ji-rong ZHONG Yi-tang WANG Li-qin HE jian-yun Shaanxi Key Laboratory of Physico-inorganic Chemistry Department of Chemical EngineeringNorthwest UniversityXi'an 710069P.R.China Conservation Technology Department the Palace MuseumBeijing 100009P R.China

N-（2,3-Dimethyl-phenyl）-N＇-（methoxyl formyl）thiourea was synthesized by the reacting of 2,3-dimethylaniline,potassium thiocyanate（KSCN） and methyl chloroformate（ClCOOCH 3）.Single crystal was obtained by slowly evaporation solvent at room *** structure was characterized by elemental analysis,IR and X-ray *** compound crystallized：a triclinic system with space group Pī,a=0.83440（12） nm,b=0.89113（13） nm,c=0.93015（13） nm,α=76.548（2） o,β=63.906（2） o,γ=82.538（2） o,V=0.60379（15） nm 3,Z=2,D c =1.311 mg/m 3,F（000）=252,μ=0.256 mm-1,R 1 =0.0379,wR 2 =*** specific heat capacity of the title compound was determined by a Micro-DSC method,and the specific heat capacity was 1.25 J·g-1 ·K-1 at 298.15 *** functions,relative to those at the standard temperature of 298.15 K,were calculated via thermodynamic *** thermal behavior of the title compound under a non-isothermal condition was studied by differential scanning calorimetry/thermogravimetric（DSC/TG） *** was an obvious endothermic peak in the DSC curve,the peak temperature was 479.43 *** compound mass loss was 89.94% observed from the TG curve.

关键词： X-Ray diffraction Acylthiourea Crystal structure Specific heat capacity Thermal behavior

Novel Magnesium Salt Based on BTATz： Crystal Structure, Thermal Behavior and Thermal Safety

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Chemical Research in Chinese Universities 2013年第4期29卷 627-631页

作者： ZHANG Xian-bo REN Ying-hui LI Wen ZHAO Feng-qi WANG Bo-zhou song ji-rong Shaanxi Key Laboratory of Physico-inorganic Chemistry School of Chemical Engineering Northwest University Xi 'an 710069 P. R. China" Science and Technology on Combustion and Explosion Laboratory Xi 'an Modern Chemistry Research Institute Xi 'an 710065 P. R. China Conservation Technology Department The Palace Museum Beijing 100009 P. R. China

A new high-energy organic magnesium salt [Mg（H2O）6]（BTATz）·2H2O[BTATz=3,6-bis（1H-1,2,3,4-tetrazol-5-yl-amino）-1,2,4,5-tetrazine] was synthesized and characterized by elemental analysis and Fourier transform infrared（FTIR） *** crystal structure was determined by X-ray single crystal *** crystal belongs to monoclinic system with space group C2/c and a=2.1329（7） nm,b=0.52275（16） nm,c=1.5909（5） nm,β=100.471（6）°,V=1.7443（9） nm3,Z=4,μ=0.361 mm-1,F（000）=900 and Dc=1.644 g/***,the thermal behavior of [Mg（H2O）6]（BTATz）·2H2O was studied under the non-isothermal conditions by differential scanning calorimetry（DSC） and thermalgravity-differential thermalgravity（TG-DTG） *** enthalpy,apparent activation energy and per-exponential factor of the main exothermic decomposition reaction are 898.88 J/g,139.2 kJ/mol and 1010.48 S-1,*** values of the self-accelerating decomposition temperature（TsADT）,the thermal ignition temperature（TTIT） and the critical temperature of thermal explosion（Tb） for [Mg（H2O）6]（BTATz）.2H2O are 515.13,532.08 and 565.99 K,respectively.

关键词： 3,6-Bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine Magnesium salt Crystal structure Thermal behavior Thermal safety

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

Intelligent reflecting surface for sum rate enhancement in MIMO systems

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Digital Communications and Networks 2024年第1期10卷 94-100页

作者： Chan-Yeob Park ji-Sung Jung Yeong-rong Lee Beom-Sik Shin Hyoung-Kyu song Department of Information and Communication Engineering Sejong UniversitySeoulGwangjin-guGunja-dong 98Republic of Korea Department of Convergence Engineering for Intelligent Drone Sejong University SeoulGwangjin-guGunja-dong 98Republic of Korea

The research for the Intelligent Reflecting Surface(IRS)which has the advantages of cost and energy efficiency has been *** capacity can be effectively increased by appropriately setting the phase value of IRS elements according to the channel ***,the problem of obtaining an appropriate phase value of IRs is difficult to solve due to the non-convex *** paper proposes an iterative algorithm for the alternating optimal solution in the Single User Multiple-Input-Multiple-Output(SU-MIMO)*** proposed iterative algorithm finds an alternating optimal solution that is the phase value of IRS one by *** results show that the proposed method has better performance than that of the randomized IRS *** number of iterations for maximizing the performance of the proposed algorithm depends on the channel state between the IRS and the receiver.

关键词： Intelligent reflecting surface MIMO Sum rate

Empirical likelihood for spatial cross-sectional data models with matrix exponential spatial specification

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 125-139页

作者： LIU Yan rong jian-rong QIN Yong-song Nanning University Nanning 530200China Center for Applied Mathematics of Guangxi and College of Mathematics and Statistics Guangxi Normal UniversityGuilin 541004China

In this paper,we study spatial cross-sectional data models in the form of matrix exponential spatial specification(MESS),where MESS appears in both dependent and error *** empirical likelihood(EL)ratio statistics are established for the parameters of the MESS *** is shown that the limiting distributions of EL ratio statistics follow chi-square distributions,which are used to construct the confidence regions of model *** experiments are conducted to compare the performances of confidence regions based on EL method and normal approximation method.

关键词： MESS empirical likelihood con dence region

Effect of structural characteristics on the transport characteristics of solid particles in the thermal storage and release system of circulating fluidized bed

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Particuology 2024年第6期89卷 22-31页

作者： Zengcai ji Guoliang song Zihua Tang Liwei Sun Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China Dalian National Laboratory for Clean Energy Dalian116023China

Coal-fired power generation stands as the most economically viable modulating power source in present-day *** holds the potential to offer prospective solutions to the challenges posed by the rapid expansion of intermittent,unpredictable,and unstable renewable energy *** particle thermal storage technology emerges as an effective means to enhance the flexibility of coal-fired circulating fluidized bed power *** attain an optimized structure for the solid particle thermal storage and release system in circulating fluidized bed units,experimental research was conducted on a 0.1 MWth circulating fluidized bed test *** study delved into the impact of ash storage bin geometries and the shapes of their feed-discharge valves on the control properties of solid particle *** experimental outcomes reveal that employing inverted m-shaped valve and dual U-shaped valves for feed control,alongside U-shaped valves and N-shaped valves for discharge control,both enable efficient and rapid storage and release of solid particles within the circulating fluidized *** similar air distribution conditions,the inverted m-shaped valve exhibits lower conveying energy consumption than the dual U-shaped valves,while the N-shaped valve excels in control characteristics over the U-shaped ***,the inverted m-shaped valve and the N-shaped valve demonstrate optimal overflow port heights,and the ash storage bin exhibits an optimum height-to-diameter ratio.

关键词： Solid particle Thermal storage System structure Transport regulation