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Solar system interplanetary communication networks:architectures, technologies and developments

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Science China(Information Sciences) 2018年第4期61卷 19-44页

作者： peng wan Yafeng ZHAN Xiaohan PAN Space Center Tsinghua University

With the development of deep space exploration technologies, main space agencies all over the world are working hard to develop the solar system interplanetary communication networks(SSICN). SSICN is a perspective communication networking system characterized by high data rate, high intelligent and perfect interconnection, which could provide the deep-space mission control and scientific application with the convenient, reliable and secure data transmission services. Following the introduction of future deep space exploration prospect, this paper analyzes the similarities and differences for three networks, terrestrial internet, near Earth space networks and SSICN, then discusses the key technologies and research trends of SSICN in details, and finally proposes the suggestions for the construction of future Chinese SSICN.

关键词： deep space exploration SSICN system architecture physical transmission network access up-layer application time synchronization

Surface Modification on Biodegradable Magnesium Alloys as Orthopedic Implant Materials to Improve the Bio-adaptability:A Review

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Journal of Materials Science & Technology 2016年第9期32卷 827-834页

作者： peng wan Lili Tan Ke Yang Institute of Metal Research Chinese Academy of Sciences

Magnesium （Mg） and its alloys as a novel kind of biodegradable material have attracted much funda- mental research and valuable exploration to develop its clinical application, Mg alloys degrade too fast at the early stage after implantation, thus commonly leading to some problems such as osteolysis, early fast mechanical loss, hydric bubble aggregation, gap formation between the implants and the tissue. Surface modification is one of the effective methods to control the degradation property of Mg alloys to adapt to the need of organism. Some coatings with bioactive elements have been developed, especially for the micro-arc oxidation coating, which has high adhesion strength and can be added with Ca, P, and Sr elements. Chemical deposition coating including bio-mimetic deposition coating, electro-deposition coating and chemical conversion coating can provide good anticorrosion property as well as better bioactivity with higher Ca and P content in the coating. From the biodegradation study, it can be seen that surface coating protected the Mg alloys at the early stage providing the Mg alloy substrate with lower degra-dation rate. The biocompatibility study showed that the surface modification could provide the cell and tissue stable and weak alkaline surface micro-environment adapting to the cell adhesion and tissue growth. The surface modification also decreased the mechanical loss at the early stage adapting to the load- bearing requirement at this stage. From the interface strength between Mg alloys implants and the surrounding tissue study, it can be seen that the surface modification improved the bio-adhesion of Mg alloys with the surrounding tissue, which is believed to be contributed to the tissue adaptability of the surface modification. Therefore, the surface modification adapts the biodegradable magnesium alloys to the need of hiodegradation, biocompatibility and mechanical loss property. For the different clinical application, different surface modificatio

关键词： Bio-adaptability Coating Biodegradable Magnesium alloys Orthopedic implants

One-step synthesis of FeO(OH)nanoparticles by electric explosion of iron wire underwater

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Defence Technology（防务技术） 2022年第1期18卷 133-139页

作者： Hao Yin Xin Gao peng-wan Chen Insitute of Systems Engineering China Acaderry of Engineering PhysicsMianyang.Sichuan 612900.China State Key Laboratory of Explosion Science and Technology Beijing Ins titute of Technology Beijing100081.China

In this study,we investigated electric explosion of iron wire in distilled water with different energy input adjusted by charging *** as-prepared samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS),showing the presence of iron and multiple iron-based compounds oxides with contents influenced by the experimental *** particular,pure FeO(OH)nanoparticles were obtained using electric explosion of iron wire with energy input of 1125 J at charging voltage of 15 *** of discharge current and resistive voltage data indicate that the high energy input induced bystrong plasma discharge at high charging voltage is a key factor to form FeO(OH).This study presents a one-step method to synthesize FeO(OH)nanoparticles using electric explosion of iron wire.

关键词： Electric wire explosion Plasma tunnel Nanopartides FeO(OH)

Enhanced strength and electrical conductivity of Al-0.3Ce alloy simultaneously with Ti(C,N)nanoparticle addition

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Rare Metals 2021年第7期40卷 1890-1896页

作者： wan-peng Li Yu-Liang Zhang Jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Ti(C,N)nanoparticles were added to an Al-0.3 Ce alloy by ultrasonic *** annealing at 570℃for4 h afforded the ultimate tensile strength of 79 MPa and electrical conductivity of 64.0%IACS for the Al-0.3 Ce alloy with1.5 vol%Ti(C,N)*** performance parameters were improved by 23.4%and 0.6%IACS,respectively,compared with those of casting refining pure aluminum(64 MPa and63.4%IACS).This could be explained by the following *** addition of Ti(C,N)nanoparticles could significantly refine the grain of Al-0.3 Ce ***,most of the coarse strip-shaped second phases distributed at the grain boundaries in Al-0.3 Ce were also transformed into spherical microparticles distributed in the grains,with micro-nano hierarchical structures comprising orientated nanosized strip phases with lengths of~400 nm and widths of~100 ***,a fine micro-nano hierarchical spherical structure could be obtained after annealing at 570℃for 4 *** numbers of micro-nano hierarchical spherical structures also increased due to the precipitation of pseudosolution Ce from the aluminum matrix during the annealing treatment.

关键词： Conductive aluminum alloy Ti(C,N)nanoparticles Ce Micro-nano hierarchical spherical structure Annealing treatment

High nitrogen nickel-free austenitic stainless steel:A promising coronary stent material

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Science China(Technological Sciences) 2012年第2期55卷 329-340页

作者： YANG Ke REN YiBin wan peng Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

Currently commercialized coronary stents are mainly made of the medical 316L stainless steel and cobalt-based alloy(L605) due to their good combination of properties,especially excellent mechanical ***,the presence of high quantity of nickel and/or cobalt elements,the agents known to trigger the toxic and allergic responses,in these materials has caused many clinic *** potential adverse effect of nickel ions release has prompted the development of high nitrogen nickel-free austenitic stainless steels for medical *** in steel is not only to replace the nickel but also improve the properties of *** this paper,the harmfulness and release of nickel from metallic stents,and the advantages in mechanical properties and hemocompatibility of high nitrogen nickel-free stainless steels for coronary stents are *** from the highlight of nickel-free,the superiority of high strength and better hemocompatibility of high nitrogen nickel-free stainless steels can guarantee to manufacture thinner strut coronary stents with remarkable anticoagulation *** nitrogen nickel-free stainless steels as a promising coronary stents material will attract more and more clinical doctors and stents makers to bring them into clinical application.

关键词： high nitrogen steel nickel-free biocompatibility coronary stent restenosis

Combustion behavior and mechanism of molecular perovskite energetic material DAP-4-based composites with metal fuel Al

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Defence Technology（防务技术） 2023年第9期27卷 53-63页

作者： peng Deng Xue-yong Guo Hua Fang Rui Liu peng-wan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

Combined with the oxidizer anions and fuel cations,molecular perovskite energetic materials show a good *** this work,the combustion behavior and mechanism of metal fuel aluminium(Al)with molecular perovskite energetic material(H_(2)dabco)[NH4(ClO_(4))_(3)](DAP-4)as a high-energy oxidant was *** DAP-4 based composites with metal fuel Al were designed and fabricated by the different mass *** showed that DAP-4 exhibits a good oxygen-supplied capacity for enhancing the combustion performance of *** maximum combustion heat of DAP-4/Al-3 at the Al/O mass ratio of 38:62 is up to 10,412 J/g in the inert gas,which is higher than those of other ratios and the mixtures of other energetic materials and *** evolution of pressure output,pressurization rate,and flame temperature was monitored for DAP-4/Al with different mass *** DAP-4/Al/F were characterized by burning *** combustion reaction mechanism of metal fuel Al with DAP-4 as a high-energy oxidant was ***-4 was ignited firstly and released acid and oxidizing gases,which corroded Al_(2)O_(3)shells on Al particle surfaces and accelerated the combustion reaction with Al to release a lot of *** work offered a new idea that molecular perovskite energetic materials have great potential in the high-energy Al-based solid rocket propellants.

关键词： DAP-4 Metal fuel al Oxidant Combustion behavior Reaction mechanism

Rational design of phosphonate/quaternary amine block polymer as an high-efficiency antibacterial coating for metallic substrates

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Journal of Materials Science & Technology 2021年第3期62卷 96-106页

作者： Li Liu wan peng Xiao Zhang Jiangmei peng Pingsheng Liu Jian Shen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Bio-functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing210023PR China Jiangsu Engineering Research Center of Interfacial Chemistry Nanjing UniversityNanjing210093PR China

Developing advanced technologies to address the bacterial associated infections is an urgent requirement for metallic implants and ***,we report a novel phosphonate/quaternary amine block polymer as the high-efficiency antibacterial coating for metallic *** pDEMMP-b-pTMAEMA block polymers that bearing identical phosphonate segments(repeat units of 15)but varied cationic segments(repeat units of 8,45,and 70)were precisely *** cationic polymer coatings were constructed on TC4 substrates based on the strong covalent binding between phosphonate group and metallic *** relationship between the segment chain length of the polymer coating and the antibacterial property endowed to the substrates have been established based on quantitative and qualitative *** showed that the antibacterial rate of the modified TC4 surface were 95.8%of *** and 92.9%of *** cells ***,unlike the cationic free polymer or cationic hydrogels,the surface anchored cationic polymers do compromise the viability of the attached C2C12 cells but without significant *** addition,the phosphonate/quate rnary amine block polymers can be easily constructed on titanium,stainless steel,and Ni/Cr alloy with significantly improved antibacterial property,indicating the generality of the block polymer for surface antibacterial modification of bio-metals.

关键词： Block polymers Polymeric coating Metallic substrates Polycations Antibacterial property

Review of channel models for deep space communications

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Science China(Information Sciences) 2018年第4期61卷 61-72页

作者： Xiaohan PAN Yafeng ZHAN peng wan Jianhua LU Space Center Tsinghua University

This paper presents a comprehensive review of channel models for deep space *** on the characteristics of environment, deep space channels can be divided into three kinds, i.e.,near Earth link, interstellar link and near planet link. The modeling for different kinds of channels are summarized respectively, and some simulation results are provided in this paper. In addition, according to the development trend of deep space communications, optical wave will become an important carrier in the future. Therefore, deep space optical communication is also briefly introduced. Finally, challenges of deep space channel modeling are pointed out and future research direction is also discussed.

关键词： deep space communication channel modeling microwave communication optical communication deep space exploration

A hybrid multiple copy routing algorithm in space delay-tolerant networks

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Science China(Information Sciences) 2017年第4期60卷 124-134页

作者： peng wan Shi CHEN Tao YU Zhongjie HUA Beijing Institute of Tracking and Telecommunications Technology National Space Science Center Chinese Academy of Sciences

With the development of technology and applications in space delay-tolerant networks(SDTNs), increasing attention has been paid on the routing technologies between different DTN nodes. This paper proposes a novel hybrid multiple copy routing(HMCR) algorithm that can be applied not only to deterministic space scenarios but also to opportunistic space scenarios. HMCR combines contact graph and delivery probability metrics to make forwarding decisions. In order to verify the new HMCR algorithm’s performance, research work has been carried out to prove its availability in SDTNs. The analysis and simulation results show that, compared with other algorithms such as contact graph routing(CGR), Epidemic, and PRo PHET, the new HMCR algorithm performs well in the areas of message delivery ratios, average end-to-end delays, and transmission overhead, which proves to be suitable for highly dynamic SDTNs.

关键词： space delay-tolerant networks routing algorithms contact graph routing hybrid single copy rout ing hybrid multiple copy routing