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A study of flames with millimeter-wave radiation

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Defence Technology（防务技术） 2020年第4期16卷 876-882页

作者： Jing-ran Xu Ru Peng chen-guang zhu Xiao Xie chen-guang Yan Department of Applied Chemistry School of Chemical EngineeringNanjing University of Science and TechnologyNanjingJiangsuChina

It is a valuable issue to explore whether a flame can radiate microwaves,in spite of the electric field formed in the *** herein is an experimental study on a series of flames with millimeterwave radiation in the combustion of pyrotechnic *** pyrotechnic films were composed of ultrafine red phosphorus(P),sodium nitrate(NaNO_3),Polyvinyl Alcohol(PVA) and some additives such as chopped carbon fibers(CFs) and aluminized glass fibers(GFs).The combustion temperatures and millimeter-wave radiation signals of the flames were measured,the millimeter-wave emissivity and spectral radiant exitance were calculated to describe the millimeter-wave radiation *** results demonstrate that the flame of the pyrotechnic films based on P/NaNO_3/CFs can radiate millimeter waves,and different materials and their proportion have a great effect on the millimeter-wave radiation intensity.

关键词： Combustion Flame Pyrotechnics Millimeter-wave radiation

Fabrication and Optical Property of Cu_7S_4 Hollow Nanoparticles Formed Through Kirkendall Effect

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Chemical Research in Chinese Universities 2008年第2期24卷 249-250页

作者： WANG chen-guang XU zhu-de LIU Run Physical Chemistry Research Institute Department of Chemistry Zhejiang University Hangzhou 310027 P. R. China

1 Introduction In recent years, there has been increasing interest in the controlled synthesis of hollow nanoparticles because of their widespread potential applications. The hollow nanoparticles can be used as catalysts, adsorbents, drug-delivery carriers, chemical reactors, and so on^[1-6]. Some nano and micro spheres are em- ployed as hard or soft templates to produce hollow structures＆[7-10].

关键词： Kirkendall effect Hollow Nanoparticle Morphology

Design and performance analysis of wireless sensor network location node system for underground mine

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Mining Science and Technology 2009年第6期19卷 813-818页

作者： chen guang-zhu SHEN Chun-feng ZHOU Li-juan School of Mechanical ＆ Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Aiming at the application of a wireless sensor network to locating miners in underground mine,we design a wireless sensor network location node system,considering the communication performance and the intrinsic safety. The location node system consists of a mobile node,several fixed nodes,and a sink node,all of whose circuits were designed based on CC2430. A varistor and a RC circuit were used in the reset circuit of a sensor node to guarantee the intrinsic safety by reducing discharge energy,the theoretical analysis of the discharge energy shows that the reset circuit is an intrinsic safety one. The analysis and simulation about the performance of the location node system are discussed,such as network communication delay and packet loss rate,the results show that the highest network communication delay of the system is about 0.11 seconds,and the highest packet loss rate is about 0.13,which assures the location node system has a high reliability,and can locate miners in the underground mine.

关键词： wireless sensor network location node network communication delay packet loss rate

Enhancing energetic performance of metal-organic complex-based metastable energetic nanocomposites by spray crystallization

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Defence Technology（防务技术） 2023年第6期24卷 203-213页

作者： Ke-xin Wang Li-xiao Shen Bin Yuan Yan Li Shun-guan zhu Lin Zhang Zhen-xin Yi chen-guang zhu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210941China

Energetic metal-organic complexes have been involved in nanothermites as novel ***,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity and functionality of the novel energetic nanocomposites are still *** this work,spray crystallization(SC)method was used to prepare novel energetic nanocomposites,the high-energy metal-organic complex[Ni(CHZ)_(3)](ClO_(4))_(2)(CHZ=1,3-diaminourea)was composited with nanoaluminum(n-Al).Results showed that n-Al/[Ni(CH_(2))_(3)](ClO_(4))_(2)energetic nanocomposites prepared by SC method increased heat release to 2977.6 J/g and peak pressure to 3.91 MPa with higher pressurization rate(1324.06 MPa/s),decreased sensitivity thresholds(>100 mJ)to electrostatic discharge(ESD)and enhanced detonation ability compared with[Ni(CHZ)_(3)](ClO_(4))_(2)alone and physically mixed(PM)n-Al/[Ni(CHZ)_(3)](ClO_(4))_(2).These results proved that it is significant to introduce energetic metal-organic complexes with inherent high energy in new-concept n-Al/energetic metal-organic complexes nanocomposites through SC method for a better performance of its application.

关键词： Energetic metal-organic complexes Nano aluminum Energetic nanocomposites Spray crystallization Thermite reaction

Sensor deployment strategy for chain-type wireless underground mine sensor network

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Journal of China University of Mining and Technology 2008年第4期18卷 561-566页

作者： chen guang-zhu zhu Zhen-cai ZHOU Gong-bo SHEN Chun-feng SUN Yan-jing School of Mechanical ＆ Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Wireless sensor networks (WSNs) are very important for monitoring underground mine safety. Sensor node deployment affects the performances of WSNs. In our study, a chain-type wireless underground mine sensor network (CWUMSN) is first pre- sented. A CWUMSN can monitor the environment and locate miners in underground mines. The lowest density deployment strate- gies of cluster head nodes are discussed theoretically. We prove that the lifetime of CWUMSN with a non-uniform deployment strategy is longer than with a uniform deployment strategy. Secondly, we present the algorithm of non-uniform lowest density de- ployment of cluster head nodes. Next, we propose a dynamic choice algorithm of cluster head nodes for CWUMSN which can im- prove the adaptability of networks. Our experiments of CWUMSN with both non-uniform lowest density and uniform lowest den- sity deployments are simulated. The results show that the lifetime of CWUMSN with non-uniform lowest density deployment is almost 2.5 times as long as that of the uniform lowest density deployment. This work provides a new deployment strategy for wire- less underground mine sensor networks and then effectively promotes the application of wireless sensor networks to underground mines.

关键词： wireless sensor networks chain-type underground mine sensor node deployment network lifetime

Aerodynamic Characteristics of Projectile with Exotic Wraparound Wings Configuration

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Journal of Harbin Institute of Technology(New Series) 2014年第3期21卷 30-37页

作者： Fu Zhang Wen-Jun Ruan Hao Wang chen-guang zhu Meng-Hua Zhang School of Energy and Power Engineering Nanjing University of Science and Technology

A projectile with exotic wraparound wings( WAW) configuration is designed to improve the finstabilized projectile shooting quality. Two fin-stabilized projectiles with the same body with and without exotic WAW configuration are simulated numerically by applying the Roe scheme. The shear-stress transport turbulence models and the lower-upper symmetric Gauss-Seidel implicit method are used to solve 3D Reynoldsaveraged Navier—Stokes equations. The differences in aerodynamic coefficients and aerodynamic characteristics of the projectiles when the Mach number varies from 0. 35 to 0. 95 are obtained,and the cause of these differences is analyzed. The calculation results indicate that the lift-to-drag ratio of the projectile significantly increases,the rolling moment decreases,and the position of the pressure center of the projectile shows relatively small changes when the exotic WAW configuration is used. Therefore,this projectile can obviously reduce rolling effect,enlarge range and improve flying stability.

关键词： exotic WAW configuration aerodynamic characteristic hybrid structure-unstructured grid overlapping grid

Exciton luminescence and many-body effect of monolayer WS2 at room temperature

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Chinese Physics B 2022年第5期31卷 670-676页

作者： Jian-Min Wu Li-Hui Li Wei-Hao Zheng Bi-Yuan Zheng Zhe-Yuan Xu Xue-Hong Zhang chen-guang zhu Kun Wu Chi Zhang Ying Jiang Xiao-Li zhu Xiu-Juan zhuang Key Laboratory for Micro-Nano Physics and Technology of Hunan Province School of Physics and ElectronicsHunan UniversityChangsha 410082China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Monolayer transition metal dichalcogenides favor the formation of a variety of excitonic quasiparticles,and can serve as an ideal material for exploring room-temperature many-body effects in two-dimensional ***,using mechanically exfoliated monolayer WS;and photoluminescence(PL)spectroscopy,exciton emission peaks are confirmed through temperature-dependent and electric-field-tuned PL *** dependence of exciton concentration on the excitation power density at room temperature is quantitatively *** concentrations covering four orders of magnitude are divided into three *** the low carrier concentration stage,the system is dominated by excitons,with a small fraction of trions and localized *** the high carrier concentration stage,the localized exciton emission from defects coincides with the emission peak position of trions,resulting in broad spectral characteristics at room temperature.

关键词： transition metal dichalcogenides photoluminescence localized exciton exciton density

CT-guided percutaneous radiofrequency ablation of spinal osteoid osteoma

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Chinese Medical Journal 2011年第23期124卷 4083-4085页

作者： LIU chen LIU Xiao-guang zhu Bin YUAN Hui-shu HAN Song-bo MA Yong-qiang Department of Radiology Peking University Third Hospital Beijing 100191 China

Background This study evaluated the feasibility, efficacy and safety of CT-guided percutaneous radiofrequency ablation in patients with spinal osteoid osteoma. Methods Two patients suffered spinal osteoid osteoma were treated with CT-guided percutaneous radiofrequency ablation under local anesthesia. Lesions located in sacral vertebrae and cervical vertebrae, which were adjacent to nerve root and spinal canal respectively. Tumors were treated under 90℃ radiofrequency temperature lasting 4 minutes by an electrode placement. Visual analog scale was used to evaluate the pain improvement. Results No complications were observed pre- and post-operation. Patients recovered to normal activities immediately and achieved complete pain relief in 24 hours. No symptoms were recurrent in 5 months and 4 months follow up. Mild scoliosis has been recovered in case 2. Conclusions CT-guided percutaneous radiofrequency ablation of spinal osteoid osteoma is safe, effective and has more clinical benefits. The long-term outcome needs further observation.

关键词： spinal tumor osteoid osteoma CT-guided radiofrequency ablation minimally invasive

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一种免疫补体优化算法

四川大学学报（工程科学版） 2009年第2期41卷 192-199页

作者：陈光柱李志蜀朱真才巩郭卫中国矿业大学机电工程学院江苏徐州221008 四川大学计算机学院四川成都610065 中国矿业大学信息与电气工程学院江苏徐州221008

针对目前提出的免疫优化算法在求解优化问题时还存在收敛速度慢,往往不能求得最优解,鲁棒性低的问题,基于生物免疫补体激活原理,提出了一种免疫补体优化算法。在算法中,依据补体激活理论,设计了主要的补体算子:分裂算子和结合算子,并根... 详细信息

针对目前提出的免疫优化算法在求解优化问题时还存在收敛速度慢,往往不能求得最优解,鲁棒性低的问题,基于生物免疫补体激活原理,提出了一种免疫补体优化算法。在算法中,依据补体激活理论,设计了主要的补体算子:分裂算子和结合算子,并根据补体激活过程,通过补体算子的作用对问题解不断优化,求得全局最优解。最后对算法的收敛性和鲁棒性进行了理论分析,并将免疫补体优化算法与经典克隆选择算法进行了对比实验。理论与实验结果表明了免疫补体优化算法是收敛的,并且收敛速度更快,求得的最优解更好,鲁棒性更高。

关键词：人工免疫系统补体激活原理优化补体算子收敛性