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Journal of Materials Science & Technology 2022年第34期129卷 96-107页

作者： H.R.zhang H.Z.Niu M.C.Zang Y.H.zhang S.liu d.l.zhang School of Materials Science and Engineering Northeastern UniversityShenyang 110819China State Key laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

An extra-low interstitial near alpha alloy Ti-3Al-2Zr-2Mo(wt%) was fabricated by hydrogenation and thermomechanical consolidation(TMC) of the coarse and spherical pre-alloyed powder with particle sizes of 60 to 270 μm. The coarse powder is a byproduct of pre-alloyed powder produced for selective laser and electron beam additive manufacturing. The TMC process involves powder compaction, fast sintering,in-situ dehydrogenation and an immediate hot extrusion to form a fully dense and fine-grained martensitic microstructure. Further dehydrogenation in vaccum at 700 °C converted the martensitic microstructure into an interwoven α/β microstructure which exhibited an improved yield strength, apparent necking and premature cracking at grain boundary α(α_(GB)) ribbons. A further annealing of 880 ℃/1 h/AC led to the formation of a fine-grained α/β_(t)composite structure, which achieved an enhance ultimate tensile strength of 835 MPa and excellent tensile ductility of 16.0%. Analysis of the deformation behavior of the alloy in different states revealed that the α/β_(t)composite structures brought about an enhanced strain hardening capability by heterogeneous deformation effect of hard β_(t)and soft α-laths, which inhibited the formation of microcracks and consequently improved the coordinated deformation.

关键词： Nearα-Ti alloy Coarse pre-alloyed powder Hydrogenation Tensile properties deformation behaviour

Effects of SiC Nanoparticle Content on the Microstructure and Tensile Mechanical Properties of Ultrafine Grained AA6063-SiC_(np) Nanocomposites Fabricated by Powder Metallurgy

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Journal of Materials Science & Technology 2017年第9期33卷 1023-1030页

作者： X.Yao Z.zhang Y.F.Zheng C.Kong M.Z.Quadir J.M.liang Y.H.Chen P.Munroe d.l.zhang State Key laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong University Electron Microscope Unit University of New South Wales School of Materials Science and Engineering University of New South Wales

Ultrafine grained AA6063-SiCnpnanocomposites with 1, 5 and 10 vol.% SiCnphave been fabricated by a novel powder metallurgy process. This process combines high energy ball milling of a mixture of 6063 alloy granules made from machining chips and Si C nanoparticles and thermomechanical powder consolidation by spark plasma sintering and hot extrusion. The microstructure and tensile mechanical properties of the samples were investigated in detail. Increasing the Si C nanoparticle content from 1 to 10 vol.%,the yield strength and ultimate tensile strength increased from 296 and 343 MPa to 545 and 603 MPa respectively, and the elongation to fracture decreased from 10.0%, to 2.3%. As expected, a higher Si C nanoparticle content generates a stronger inhibiting effect to grain growth during the thermomechanical powder consolidation process. Analysis of the contributions of various strengthening mechanisms shows that a higher Si C nanoparticle content leads to a higher contribution from nanoparticle strengthening, but grain boundary strengthening still makes the largest contribution to the strength of the *** the Si C nanoparticle content increased to 10 vol.%, the failure of the nanocomposite was initiated at weakly-bonded interparticle boundaries(IPBs), indicating that with a high flow stress during tensile deformation, the failure of the material is more sensitive to the presence of weakly-bonded IPBs.

关键词： Metal matrix nanocomposite Ultrafine grained material Powder metallurgy Tensile mechanical properties

The design and performance of charged particle detector onboard the GECAM mission

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Radiation detection Technology and Methods 2022年第1期6卷 53-62页

作者： Y.B.Xu X.Q.li X.l.Sun S.Yang H.Wang W.X.Peng X.H.liang K.Gong Y.Q.liu d.Y.Guo X.Y.Zhao C.Y.li Z.H.An J.J.He X.J.liu X.Y.Wen S.l.Xiong Fan zhang d.l.zhang C.Y.zhang C.Cai Z.Chang G.Chen C.Chen Y.Y.du M.Gao R.Gao d.J.Hou Y.G.li G.li l.li X.F.li M.S.li F.J.lu H.lu B.Meng F.Shi J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao Y.P.Xu J.W.Yang Q.B.Yi S.N.zhang C.M.zhang F.zhang Y.Zhao X.Zhou Key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Background The Gravitational wave highly energetic Electromagnetic Counterpart All-sky Monitor(GECAM)is dedicated to detecting gravitational wave gamma-ray *** is capable of all-sky monitoring over and discovering gamma-ray bursts and new radiation *** consists of two microsatellites,each equipped with 8 charged particle detectors(CPds)and 25 gamma-ray detectors(GRds).Purpose The CPd is used to measure charged particles in the space environment,monitor energy and flow intensity changes,and identify between gamma-ray bursts and space charged particle events in conjunction with *** CPd uses plastic scintillator as the sensitive material for detection,silicon photomultiplier array as the optically readable device,and the inlaid Am-241 radioactive source as the onboard calibration *** In this paper,we will present the working principle,physical design,functional implementation and preliminary performance test results of the *** a result,the energy range of electron,gamma-ray detection efficiency and dead time are tested to be better than the indexes required through the ground calibration experiment.

关键词： GECAM CPd SiPM

The data acquisition algorithm designed for the SiPM-based detectors of GECAM satellite

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Radiation detection Technology and Methods 2022年第1期6卷 70-77页

作者： Y.Q.liu K.Gong X.Q.li X.Y.Wen Z.H.An C.Cai Z.Chang G.Chen C.Chen Y.Y.du M.Gao R.Gao d.Y.Guo J.J.He d.J.Hou Y.G.li C.Y.li G.li l.li X.F.li M.S.li X.H.liang X.J.liu F.J.lu H.lu B.Meng W.X.Peng F.Shi X.l.Sun H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.l.Xiong Y.B.Xu Y.P.Xu S.Yang J.W.Yang Q.B.Yi Fan zhang d.l.zhang S.N.zhang C.Y.zhang C.M.zhang Fei zhang X.Y.Zhao Y.Zhao X.Zhou Key laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Physics and Space Science College China West Normal UniversityNanchong 637002China

Background The Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor(GECAM)consists of 2 microsatellites,each of which contains 25 GRd(laBr3)detectors and 8 CPd(plastic scintillator)*** silicon photomultiplier(SiPM)array is used to read each *** output signal of these detectors with SiPM array is very special and challenging to *** this study,a novel data acquisition(dAQ)algorithm for these detectors is designed and implemented,and the content of the output event packet is *** and Conclusion The performances,including the event acquisition efficiency of this dAQ algorithm,are extensively verified through experimental *** the on-ground and in-flight tests,this algorithm has excellent performance despite the very limited resources and short development time of GECAM mission.

关键词： Silicon photomultiplier digital waveform processing data acquisition

dedicated SiPM array for GRd of GECAM

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Radiation detection Technology and Methods 2022年第1期6卷 63-69页

作者： d.l.zhang X.l.Sun Z.H.An X.Q.li X.Y.Wen K.Gong C.Cai Z.Chang G.Chen C.Chen Y.Y.du M.Gao R.Gao d.Y.Guo J.J.He d.J.Hou Y.G.li C.Y.li G.li l.li X.F.li M.S.li X.H.liang X.J.liu Y.Q.liu F.J.lu H.lu B.Meng W.X.Peng F.Shi H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.l.Xiong Y.B.Xu Y.P.Xu S.Yang1 X.Zhou J.W.Yang Fan zhang S.N.zhang C.Y.zhang C.M.zhang Fei zhang X.Y.Zhao Institute of High Energy Physics CASBeijing 100049China State Key laboratory of Particle detection and Electronics Beijing 100049China

Purpose The discovery of gravitational waves and gamma-ray bursts heralds the era of multi-messenger *** the adoption of two small satellites to achieve the all-sky monitoring of gamma-ray bursts,the gravitational wave highenergy electromagnetic counterpart all-sky monitor(GECAM)possesses a quasi-real-time early warning ability and plays an important role in positioning the sources of gravitational waves and in subsequent *** satellite of GECAM was fitted with 253-inch-diameter gamma-ray detectors(GRd),covering an energy range of 8–2 *** have adopted silicon photomultiplier tubes(SiPM)in lieu of photomultiplier tubes(PMT)to adapt to the dimensional limitations of *** A unique 3-inch circular SiPM array was *** this design,646×6 mm chips were arranged evenly in a circular manner with the seams filled with reflecting films,thus achieving satisfactory uniformity of light *** integrated pre-amplifier circuit on the back of the SiPM array adopted two-level grouping and summing;further,it achieved a satisfactory signal-to-noise *** high-gain and low-gain channels were adopted to achieve a large dynamic range,and two independent power supply units were used,where each unit can be closed separately,thus improving *** Performance studies show that this SiPM array meets the requirements of *** A 3-inch SiPM array have been developed that uses grouped summation,reflective films,a circular arrangement,two groups of independent power supplies,high-and low-gain signals,differential signal output technologies,*** solution can be used not only for GECAM,but also as a general solution for SiPM-based scintillation detectors.

关键词： SiPM GECAM Gamma-ray Signal-to-noise ratio Reflecting film Pre-amplifier

Microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in Manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki Nan zhang Michael d.Gilchrist School of Mechanical and Materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2d computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： Micro feature shaping and electropolishing Micro mould tools Green electrolyte demoulding micro patterns

Quality assurance test and failure analysis of SiPM arrays of GECAM satellites

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Radiation detection Technology and Methods 2022年第1期6卷 35-42页

作者： d.l.zhang M.Gao X.l.Sun X.Q.li Z.H.An X.Y.Wen C.Cai Z.Chang G.Chen C.Chen Y.Y.du R.Gao K.Gong d.Y.Guo J.J.He d.J.Hou Y.G.li C.Y.li G.li l.li X.F.li M.S.li X.H.liang X.J.liu Y.Q.liu F.J.lu H.lu B.Meng W.X.Peng F.Shi H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.l.Xiong Y.B.Xu Y.P.Xu S.Yang J.W.Yang Fan.zhang S.N.zhang C.Y.zhang C.M.zhang Fei zhang X.Y.Zhao X.Zhou Institute of High Energy Physics CASBeijing 100049People’s Republic of China

Background The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)satellite developed a SiPM-based gamma-ray detector to monitor the gravitational wave-related GRBs and guide subsequent observations in other wavelengths of *** As all the available SiPM devices belong to commercial grade,quality assurance tests need to be performed in accordance with the aerospace *** In the SiPM application of GECAM,quality assurance experiments were *** mechanism of the failure of SiPM devices was analyzed during the development *** Based on the quality assurance test results,the fnal pass rate of SiPM array was 95%.Based on the failure analysis,it was found that a piece of SiPM had a leakage channel after longtime operation due to device *** According to the accumulated experience,in the reliability test of SiPM,it is necessary to pay special attention to test the impedance of each pin of SiPM to ground and confrm that the power switch state of SiPM is controllable.

关键词： Gravitational waves Gamma-ray detectors Silicon photomultipliers Quality assurance test Failure analysis

Evaluation of protective immune responses induced by recombinant vaccines of TRXl and ENO2 against Toxoplasma gondii in BAlB/c mice

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Evaluation of protective immune responses induced by recombi...

The technology for detection of gamma-ray burst with GECAM satellite

中国畜牧兽医学会兽医寄生虫学分会第十三次学术研讨会

作者： M.Wang X.Y.Yang N.Z.zhang d.l.zhang X.Q.Zhu State Key laboratory of Veterinary Etiological Biology Key Laboratory of Veterinary Parasitology of Gansu ProvinceLanzhou Veterinary Research InstituteChinese Academy of Agricultural Sciences Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious diseases and Zoonoses Yangzhou University College of Veterinary Medicine

Toxoplasma gondii is an obligate intracellular parasite that can infect almost all species of warm-blooded animals,and causing severe toxoplasmosis *** chemical treatments could be available fully cure the disease,and thus *** vaccine may be an ideal *** order to evaluate the effects of TRXl and EN02 from ***,those two genes were amplified and linked into the prokaryotic expression *** the purified TRXl,EN02 and the mixed TRXl+EN02 were emulsified with Freund’s adjuvant,respectively,to construct protein *** of BAlB/c mice with these three protein vaccines could induce strong immune responses and a strong lymphoproliferative *** chronic infection,the numbers of brain cysts of the mice immunized with those three protein vaccines reduced significantly when compared with those in control groups(P dy suggests that *** TRXl protein and ENO2 protein may be ideal candidates for vaccines of toxoplasmosis.

关键词： Toxoplasma gondii thioredoxin-like enolase2 protein vaccine immunity

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Radiation detection Technology and Methods 2022年第1期6卷 12-25页

作者： X.Q.li X.Y.Wen Z.H.An C.Cai Z.Chang G.Chen C.Chen Y.Y.du M.Gao R.Gao K.Gong d.Y.Guo J.J.He d.J.Hou Y.G.li C.Y.li G.li l.li X.F.li M.S.li X.H.liang X.J.liu Y.Q.liu F.J.lu H.lu B.Meng W.X.Peng F.Shi X.l.Sun H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao S.l.Xiong Y.B.Xu Y.P.Xu S.Yang J.W.Yang Q.B.Yi d.l.zhang Fan zhang S.N.zhang C.Y.zhang C.M.zhang Fei zhang X.Y.Zhao Y.Zhao X.Zhou C.S.zhang J.P.Yu l.Chang K.K.zhang J.Huang Y.M.Chen X.B.Han Institute of High Energy Physics CASBeijing 100049China Xiangtan University Xiangtan 411105China Beijing Normal University Beijing 110875China Beijing Glass Research Institute Beijing 101100China Innovation Academy for Microsatellites of CAS Shanghai 201204China

Introduction The main physical objective of the GECAM satellite is to detect gamma-ray bursts,which is related to gravitational waves of double compact object *** GECAM satellite also detects and investigates various bursts of high-energy celestial *** and methods In this study,we designed,developed and calibrated the payload and launched it into orbit with GECAM *** payload consists of the gamma ray detector(GRd,for detecting 4 keV–4 MeV X/γray),the charged particle detector(CPd,for detecting 150 keV–5 MeV charged particle),and the electronic box(EBOX).The all-sky field coverage is achieved via two 229-degree large-area satellites positioned 180 degrees apart and are on opposite sides of the *** satellite is equipped with 25 GRds and 8 CPds;thus,the satellite can identify charged particle bursts in ***-ray detectors adopt lanthanum bromide crystal technology combined with silicon *** is the first time that this technology was used massively in space *** The GECAM satellite can quickly determine the direction of gamma-ray bursts(positioning)via indexing and fitting method,while the transmit variability,energy spectrum and direction of the gamma-ray bursts guide subsequent observations through the Beidou-3 RdSS in quasi-real *** will play an important role in the study of high energy celestial bursts.

关键词： GECAM Gamma-ray burst lanthanum bromide crystal Silicon photomultiplier Beidou short message

The design and performance of GRd onboard the GECAM satellite

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Radiation detection Technology and Methods 2022年第1期6卷 43-52页

作者： Z.H.An X.l.Sun d.l.zhang S.Yang X.Q.li X.Y.Wen K.Gong X.H.liang X.J.liu Y.Q.liu Y.G.li S.l.Xiong Y.B.Xu Fan zhang X.Y.Zhao C.Cai Z.Chang G.Chen C.Chen Y.Y.du P.Y.Feng M.Gao R.Gao d.Y.Guo J.J.He d.J.Hou C.Y.li G.li l.li X.F.li M.S.li F.J.lu H.lu B.Meng W.X.Peng F.Shi H.Wang J.Z.Wang Y.S.Wang H.Z.Wang X.Wen S.Xiao Y.P.Xu J.W.Yang Q.B.Yi S.N.zhang C.Y.zhang C.M.zhang Fei zhang Y.Zhao X.Zhou CAS Institute of High Energy PhysicsBeijing 100049China State Key laboratory of Particle detection and Electronics Beijing 100049China 3 Xiangtan UniversityXiangtan 411105China 4 Beijing Normal UniversityBeijing 110875China Xiangtan University Xiangtan 411105China Beijing Normal University Beijing 110875China

Background Each GECAM satellite payload contains 25 gamma-ray detectors(GRds),which can detect gamma-rays and particles and can roughly localize the Gamma-Ray Bursts(GRBs).GRd was designed using lanthanum bromide(laBr3)crystal as the sensitive material with the rear end coupled with silicon photomultiplier(SiPM)array for *** In aerospace engineering design of GRd,there are many key points to be *** this paper,we present the specific design scheme of GRd,the assembly and the performance test results of *** Based on Monte Carlo simulation and experimental test results,the specific schematic design and assembling process of GRd were *** being fully assembled,the GRds were conducted performance tests by using radioactive source and also conducted random vibration *** and conclusion The test results show that all satellite-borne GRds have energy resolutionllite in scientific *** random vibration test shows that GRd can maintain in a stable performance,which meets the requirement of spatial application.

关键词： lanthanum bromide scintillator SiPM array GECAM Gamma-ray detector Energy resolution