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Coating processes towards selective laser sintering of energetic material composites

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Defence Technology（防务技术） 2020年第2期16卷 316-324页

作者： Zetu Jiba Walter W.Focke Lonji Kalombo Moshawe J.Madito Council for Scientific and Industrial Research(CSIR) Defence Peace Safety and SecurityP.O Box 395Pretoria 0001South Africa University of Pretoria South Africa CSIR Chemical ClusterSouth Africa

This research aims to contribute to the safe methodology for additive manufacturing(AM)of energetic materials.Coating formulation processes were investigated and evaluated to find a suitable method that may enable selective laser sintering(SLS)as the safe method for fabrication of high explosive(HE)compositions.For safety and co nvenie nce reasons,the co ncept demonstration was conducted using inert explosive simulants with properties quasi-similar to the real HE.Coating processes for simulant RDXbased microparticles by means of PCL and 3,4,5-trimethoxybenzaldehyde(as TNT simulant)are reported.These processes were evaluated for uniformity of coating the HE inert simulant particles with binder materials to facilitate the SLS as the adequate binding and fabrication method.Suspension system and single emulsion methods gave required particle near spherical morphology,size and uniform coating.The suspension process appears to be suitable for the SLS of HE mocks and potential formulation methods for active HE composites.The density is estimated to be comparable with the current HE compositions and plastic bonded explosives(PBXs)such as C4 and PE4,produced from traditional methods.The formulation method developed and understanding of the science behind the processes paves the way toward safe SLS of the active HE compositions and may open avenues for further research and development of munitions of the future.

关键词： Coating processes energetic materials Simulants Mock explosives Additive manufacturing Selective laser sintering

In situ evidence of resonant interactions between energetic electrons and whistler waves in magnetopause reconnection

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Earth and Planetary Physics 2019年第6期3卷 467-473页

作者： Zhi Li QuanMing Lu RongSheng Wang XinLiang Gao HuaYue Chen Chinese Academy Sciences Key Laboratory of Geospace Environment Department of Geophysics and Planetary ScienceUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy Sciences Center for Excellence in Comparative Planetology Hefei 230026China

In this paper,we analyze one reconnection event observed by the Magnetospheric Multiscale(MMS)mission at the earth’s magnetopause.In this event,the spacecraft crossed the reconnection current sheet from the magnetospheric side to the magnetosheath side,and whistler waves were observed on both the magnetospheric and magnetosheath sides.On the magnetospheric side,the whistler waves propagated quasi-parallel to the magnetic field and toward the X-line,while on the magnetosheath side they propagated almost anti-parallel to the magnetic field and away from the X-line.Associated with the enhancement of the whistler waves,we find that the fluxes of energetic electrons are concentrated around the pitch angle 90°when their energies are higher than the minimum energy that is necessary for the resonant interactions between the energetic electrons and whistler waves.This observation provides in situ observational evidence of resonant interactions between energetic electrons and whistler waves in the magnetic reconnection.

关键词： magnetic reconnection whistler waves magnetosphere energetic electrons

energetic death: The unknown phase of thanatology

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Journal of Acute Disease 2018年第6期7卷 225-233页

作者： Adriánángel Inchauspe Hainan Medical University.Haikou HainanChina

The large amount of classifications about the concept of death from a medical-legal perspective leads us to think that there are still many aspects to accurately define that precise moment in which the end of our earthly existence is considered as a final and unalterable fact. An answer to such a question may come from a retrospective analysis of those victims of impending-death situations that have been rescued after both basic and advanced cardiac pulmonary resuscitation failure and their consequent medical-legal death declaration. The aim of the following work is to introduce a new phase within forensic thanatology, supported by a complementary resuscitation maneuver based upon millennial traditional Chinese medicine principles together with a detailed analysis of current global agreements on organ transplantation and an avant-garde perspective on actual knowledge about cell death. Those terms will then allow us to achieve a holistic view of said concept, still loosely defined at present. Such an innovative diagnostic-therapeutic resource can in turn enable us to evaluate and face the irreversibility of such extreme situation, analyzing the statistical feasibility of its promising results.

关键词： Thanatology energetic death Chinese medicine Cell death Organ transplantation

Changes in energetic profile of pregnant ewes in relation with the composition of the fetal fluids

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Asian Pacific Journal of Tropical Biomedicine 2016年第3期6卷 256-258页

作者： Samia Haffaf Bouabdellah Benallou Institute of Agro-Veterinary Sciences University of Batna Institute of Veterinary Sciences University of Tiaret

Objective: To evaluate the energetic profile of fetal fluids and to make comparisons of the concentrations of the constituents present with those in the maternal plasma.Methods: A study was conducted in 102 gravid sheep uteri. The four stages of gestation as Stage I(0–60 days), Stage II(61–90 days), Stage III(91–120 days) and Stage IV(121–145 days) were identified based on the crown anus length of the embryo/fetus. The amniotic and allantoic fluids collected from the gravid uteri of each group were subjected to biochemical analysis of glucose, cholesterol and triglyceride.Results: The levels of glucose and triglyceride in maternal plasma were lower(P 0.05) of plasma cholesterol levels was detected between the sampling periods.Contrariwise, cholesterol concentrations of fetal fluids were higher in Stages III and IV of pregnancy when compared with the Stages I and II.Conclusions: The influence of pregnancy on the biochemical composition of fetal fluids was statistically significant.

关键词： energetic profile Fetal fluid Ewes Pregnancy

Alfvén eigenmode stability analysis and energetic particle transport prediction for CFETR hybrid scenario

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Plasma Science and Technology 2019年第9期21卷 46-51页

作者：邹云鹏叶民友 School of Physical Science University of Science and Technology of China

The hybrid scenario is a projection for CFETR operation with high plasma current and density.Therefore, the energetic particles(EPs) generated by fusion reactions can destabilize Alfvén eigenmodes(AEs), which could result in significant EPs loss and redistribution. Both the eigenvalue code NOVA-K and the wrapped local stability code TGLFEP are used to analyze AE stability. The simulation indicates the beta-induced Alfvén eigenmodes with n?>?5 in the core region are the most unstable. The NOVA-K code is used to benchmark the critical density gradient calculated by TGLFEP. In addition, the EPtran code is employed to predict EP transport induced by unstable AEs and turbulence, which reduce EP density in the core and drive approximately 30% EP transport from the core to the edge, thus the EP density profile flattens and EPs with lower energy deposit near the edge.

关键词： CFETR energetic particle Alfvén eigenmodes critical gradient model

Imaging energetic electron spectrometer onboard a Chinese navigation satellite in the inclined GEO orbit

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Science China(Technological Sciences) 2018年第12期61卷 1845-1865页

作者： ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei ZOU JiQing CHEN Jiang SHI WeiHong YU XiangQian ZHONG WeiYing WANG YongFu ZHOU XuZhi HAO YiXin CHEN XingRan JIA XiangHong XU Feng SHAO SiPei WANG Bo HAO XiaoYun ZHANG XiaoXin Institute of Space Physics and Applied Technology Peking University Beijing 100871 China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center Beijing 100094 China Shandong Aerospace Electro-technology Yantai 264000 China Key Laboratory of Space Weather National Center for Space Weather Beijing 100081 China

The energetic electron measurement is one of the most important issues to understand dynamics in space physics and the applications for space weather. In this study, the principle and functional components of the imaging energetic electron spectrometer(IES) onboard a Chinese navigation satellite in the inclined GEO orbit(IGSO) was introduced. The IES instrument is developed by the team in Peking University(BeiDa), thus it is named as BD-IES. Based on the pin-hole technique, the instrument can measure 50–600 keV electrons incident from 9 directions over a range of 180° in polar angle. With pulse height analysis(PHA), the spectrum can be determined for each direction. The energy and angular calibrations were performed, which show the good energy and angular characteristics of BD-IES. Monte Carlo simulations show that the anti-proton design of BDIES can effectively decrease the proton contamination on the electron measurements in the inclined GEO orbit. The primary results of BD-IES verify the successful design of this instrument.

关键词： imaging energetic electron spectrometer pin-hole imaging system IGSO satellite

Monte Carlo simulations of the sensor head of imaging energetic electron spectrometer onboard a Chinese IGSO navigation satellite

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Science China(Technological Sciences) 2019年第7期62卷 1169-1181页

作者： ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei LUO Lin ZHOU XuZhi CHEN XingRan HAO YiXin REN Jie WANG YongFu SHI WeiHong YU XiangQian JIA XiangHong XU Feng ZHANG XiaoXin Institute of Space Physics and Applied Technology Peking University Beijing 100871 China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center Beijing 100094 China Key Laboratory of Space Weather National Center for Space Weather Beijing 100081 China

An imaging energetic electron spectrometer built by the Peking University team(BD-IES) onboard a Chinese navigation satellite in an inclined GEO orbit has been launched successfully in September 2015, which measures the spectra of the energetic electrons with the energy range of 50–600 keV in nine directions. In this study, Monte Carlo simulations of the BD-IES sensor head were performed using Geant4 and the corresponding characteristic responses to the isotropic energetic particles were derived. The effective geometric factors were estimated using the typical electron and proton spectra in the GEO orbit and the corresponding simulated sensor head responses. It was found that the average effective geometric factors of nine directions are close to the nominal geometric factors calculated with the traditional method, but the effective geometric factor decreases as the center energy of the energy channel decreases. The BD-IES sensor head also responses to the energetic protons, but the average contamination rate of all 72 channels is about 2%, which means that the proton contamination is acceptable. The spectra of the energetic electrons measured by BD-IES are derived using the effective geometric factors of the sensor head and are comparable with the spectra measured by the magnetic electron ion spectrometer(MagEIS) instrument onboard Van Allen Probes.

关键词： Monte Carlo simulation pin-hole imaging system geometric factor imaging energetic electron spectrometer IGSO satellite

Ultra low frequency waves impact on radiation belt energetic particles

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Science China(Technological Sciences) 2009年第12期52卷 3698-3708页

作者： ZONG QiuGang HAO YongQiang WANG YongFu Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

One of the most fundamental important issues in the space physics is to understand how solar wind energy transports into the inner magnetosphere.Ultra low frequency(ULF)wave in the magnetosphere and its impact on energetic particles,such as the wave-particle resonance,modulation,and particle acceleration,are extremely important topics in the Earth’s radiation belt dynamics and solar wind― magnetospheric coupling.In this review,we briefly introduce the recent advances on ULF waves study. Further,we will explore the density structures and ion compositions around the plasmaspheric boundary layer(PBL)and discuss its possible relation to the ULF waves.

关键词： radiation belt particle ULF wave wave-particle interaction(WPI) energetic particles acceleration plasmaspheric boundary layer oxygen ions

一种新型富氮含能盐(MGTZ)(PA)的结构分析(英)

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含能材料 2012年第2期20卷 260-261页

作者：梁彦会张建国谢少华冯金玲张同来舒远杰 State Key Laboratory of Explosion Science and Technology Beijing Institute of technology Institute of Chemical Materials China Academy of Engineering Physics

Recently,materials with high nitrogen content such as triazole,tetrazole,and tetrazine derivatives have received attention due to their highdensities,high heats of formation,and high thermal stability.The 3-and 6-positions of stetrazine have high activity and can besubstituted by a soft neutral heteroatom or carbanion nucleophiles,so the

关键词： physical chemistry nitrogen-rich energetic salt 3-methoxy-6-guanidine-s-tetrazine(MGTZ) picric acid(PA) crystal structure