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Development of a high-speed digital pulse signal acquisition and processing system based on MTCA for liquid scintillator neutron detector on EAST

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Nuclear Science and Techniques 2023年第10期34卷 60-72页

作者： Yong-qiang Zhang Li-Qun Hu guo-qiang zhong Hong-Rui Cao Jin-Long Zhao Li Yang qiang Li Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China

In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was employed. This decision was based on the detector's superior sensitivity, optimal time-response, and its exceptional n–γ discrimination capability. This detector emits fast pulse signals that are as narrow as 100 ns, with high count rates that can peak at several Mcps. However, conventional nuclear circuits faced challenges in performing pulse height analysis, n–γ pulse shape discrimination, and in recording the entire pulse waveform under such high count rate conditions. To address these challenges, a high-speed digital pulse signal acquisition and processing system was designed. The system was developed around a micro-telecommunications computing architecture. Within this structure, a signal acquisition and processing(SAQP) module communicated through PCI Express links, achieving a bandwidth of up to 1.6 GB/s. To accurately capture the detailed shape of the pulses, four channels of analog-to-digital converters were used, each with a 500-MSPS sampling rate and a 14-bit resolution, ensuring an accuracy that surpassed 11 bits. An n–γ discrimination algorithm, based on the two-gate integral method, was also developed. Implemented within field programmable gate arrays, this algorithm provided a real-time n–γ discrimination spectrum for pulse height analysis. The system underwent rigorous testing in a laboratory setting and during an EAST experiment. The results confirmed that the innovative SAQP system can satisfy the demanding requirements of high-parameter experiments, manage count rates of up to 2 Mcps, execute real-time n–γ discrimination algorithms, and record entire pulse waveforms without any data loss.

关键词： EAST NES High-speed MTCA n–γdiscrimination Entire pulse waveform

Study on the gamma rays and neutrons energy response optimization of a scintillating fiber detector for EAST with Geant4

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Nuclear Science and Techniques 2023年第9期34卷 40-49页

作者： Wei-Kun Chen Li-Qun Hu guo-qiang zhong Rui-Jie Zhou Bing Hong qiang Li Li Yang Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Institute of Energy Hefei Comprehensive National Science Center(Anhui Energy Laboratory)Hefei 230031China

A new scintillating fiber detector inside magnetic shielding tube was designed and assembled for use in the next round of fusion experiments in the experimental advanced superconducting tokamak to provide D–T neutron yield with time *** this study,Geant4 simulations were used to obtain the pulse height spectra for ideal signals produced when detecting neutrons and gamma rays of multiple *** of the main sources of interference was found to be low-energy neutrons below 10–5 MeV,which can generate numerous secondary particles in the detector components,such as the magnetic shielding tube,leading to high-amplitude output *** address this issue,a compact thermal neutron shield containing a 1-mm Cd layer outside the magnetic shielding tube and a 5-mm inner Pb layer was specifically *** effects on the measurement of fast neutrons and the shielding effect on gamma rays were *** can suppress the height of the signals caused by thermal neutrons to a level below the height corresponding to neutrons above 4 MeV because the yield of the latter is used for detector *** addition,the detector has relatively flat sensitivity curves in the fast neutron region,with the intrinsic detection efficiencies(IDEs)of approximately 40%.For gamma rays with energies that are not too high(<8 MeV),the IDEs of the detector are only approximately 20%,whereas for gamma rays below 1 MeV,the response curve cuts off earlier in the low-energy region,which is beneficial for avoiding counting saturation and signal accumulation.

关键词： Sci-Fi detector D–T fusion neutron Thermal neutron shield Energy response Geant4

Development of a wide-range and fast-response digitizing pulse signal acquisition and processing system for neutron flux monitoring on EAST

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Nuclear Science and Techniques 2022年第3期33卷 126-136页

作者： Li Yang Hong-Rui Cao Jin-Long Zhao Zi-Han Zhang qiang Li guo-Bin Wu Yong-qiang Zhang guo-qiang zhong Li-Qun Hu Zi-Jun Zhang Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Hefei University of Technology Hefei 230009China

The neutron count rate fluctuation reaches six orders of magnitude between the ohmic plasma scenario and high power of auxiliary heating on an experimental advanced superconducting tokamak(EAST).The measurement result of neutron flux monitoring(NFM)is a significant feedback parameter related to the acquisition of radiation protection-related information and rapid fluctuations in neutron emission induced by plasma magnetohydrodynamic ***,a wide range and high time resolution are required for the NFM system on *** satisfy these requirements,a digital pulse signal acquisition and processing system with a wide dynamic range and fast response time was *** present study was conducted using a field-programmable gate array(FPGA)and peripheral component interconnect extension for instrument express(PXIe)*** digital dual measurement modes,which are composed of the pulse-counting mode and AC coupled square integral's Campbelling mode,were designed to expand the measurement range of the signal acquisition and processing *** time resolution of the signal acquisition and processing system was improved from 10 to 1 ms owing to utilizing highspeed analog-to-digital converters(ADCs),a high-speed PXIe communication with a direct memory access(DMA)mode,and online data preprocessing technology of *** signal acquisition and processing system was tested experimentally in the EAST radiation *** test results showed that the time resolution of NFM was improved to 1 ms,and the dynamic range of the neutron counts rate was expanded to more than 10^(6) counts per *** Campbelling mode was calibrated using a multipoint average linear fitting method;subsequently,the fitting coefficient reached ***,the newly developed pulse signal acquisition and processing system ensures that the NFM system meets the requirements of high-parameter experiments conducted on EAST more effectively.

关键词： EAST Neutron flux monitoring High time resolution Wide range Pulse signal acquisition and processing system

Optimization study and design of scintillating fiber detector for DT neutron measurements on EAST with Geant4

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Nuclear Science and Techniques 2022年第11期33卷 33-45页

作者： Wei-Kun Chen Li-Qun Hu guo-qiang zhong Bing Hong Rui-Jie Zhou Kai Li Li Yang Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Hefei Comprehensive National Science Center Institute of EnergyHefei 230031China School of Mechanical and Vehicle Engineering West Anhui UniversityLuan 237012China

Real-time monitoring of the 14-MeV D-T fusion neutron yield is urgently required for the triton burnup study on the Experimental Advanced Superconducting Tokamak (EAST). In this study, we developed an optimal design of a fast-neutron detector based on the scintillating fiber (Sci-Fi) to provide D-T neutron yield through Geant4simulation. The effect on the detection performance is concerned when changing the number of the Sci-Fis embedded in the probe head, minimum distance between the fibers, length of the fibers, or substrate material of the probe head. The maximum number of scintillation photons generated by the n/γ source particles and output by the light guide within an event (event:the entire simulation process for one source particle) was used to quantify the n/γ resolution of the detector as the main basis. And the intrinsic detection efficiency was used as another evaluation criterion. The results demonstrate that the optimal design scheme is to use a 5 cm probe head whose substrate material is pure aluminum, in which 463 Sci-Fis with the same length of 5 cm are embedded, and the minimum distance between the centers of the two fibers is 2 mm. The optimized detector exhibits clear directionality in the simulation, which is in line with the expectation and experimental data provided in the literature. This study presents the variation trends of the performance of the SciFi detector when its main parameters change, which is beneficial for the targeted design and optimization of the Sci-Fi detector used in a specific radiation environment.

关键词： Sci-Fi detector Optimal design n/c resolution Intrinsic detection efficiency Geant4

Microvesicles with mitochondrial content are increased in patients with sepsis and associated with inflammatory responses

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World Journal of Clinical Cases 2023年第2期11卷 342-356页

作者： Hai-Jun Zhang Jin-Yi Li Chao Wang guo-qiang zhong Department of Cardiology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530000Guangxi Zhuang Autonomous RegionChina Department of Cardiology The First Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421000Hunan ProvinceChina Department of Cardiology The Affiliated Hospital of Guilin Medical UniversityGuilin 541000Guangxi Zhuang Autonomous RegionChina

BACKGROUND Endothelial activation plays an important role in sepsis-mediated inflammation,but the triggering factors have not been fully *** carrying mitochondrial content(mitoMVs)have been implicated in several diseases and shown to induce endothelial *** To explore whether mitoMVs constitute a subset of MVs isolated from plasma of patients with sepsis and contribute to endothelial *** MVs were isolated from human plasma and characterized by confocal microscopy and flow *** cytokines,including interleukin(IL)-6,IL-8 and tumour necrosis factor(TNF)-α,and soluble vascular cell adhesion molecule(sVCAM)-1 were detected by *** umbilical vein endothelial cells(HUVECs)were stimulated with the circulating MVs to evaluate their effect on endothelial *** MitoMVs were observed in plasma from patients with *** with those in healthy controls,expression of MVs,mitoMVs,proinflammatory cytokines and sVCAM-1 was *** number of mitoMVs was positively associated with TNF-αand *** vitro,compared with MVs isolated from the plasma of healthy controls,MVs isolated from the plasma of patients with sepsis induced expression of OAS2,RSAD2,and CXCL10 in *** were taken up by HUVECs,and sonication of MVs significantly reduced the uptake of mitoMVs by HUVECs and expression of the above three type I IFNdependent *** MitoMVs are increased in the plasma of patients with sepsis,which induces elevated expression of type I IFN-dependent *** suggests that circulating mitoMVs activate the type I IFN signalling pathway in endothelial cells and lead to endothelial activation.

关键词： Sepsis Microvesicles Mitochondria Microvesicles carrying mitochondrial content

Activation and shutdown dose-rate analyses for the EAST NBI test facility

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Nuclear Science and Techniques 2016年第4期27卷 60-66页

作者： Yu-Qing Chen Ji Wang Bin Wu Jun Li Ya-Hong Xie guo-qiang zhong Chun-Dong Hu Institute of Plasma Physics Chinese Academy of Sciences

An analysis of the neutron activation and shutdown dose rates was performed for the EAST high-power deuterium neutral beam injector test facility(EAST NBITF) by using the multiparticle transport code FLUKA2011.2. Also, the neutron and neutron-induced gamma spectra of the facility's vacuum vessel were evaluated. The results identified the major radionuclides^(99) Mo,^(65)Ni,^(58) Co,^(56)Mn, and^(51) Cr for the vacuum vessel and the primary nuclide^(64) Cu for both the ion dump and the *** simulated results indicated that, when the EAST NBITF operates within the design parameters of deuterium energy 80 ke V, current 50 A, and pulse 100 s, the neutron intensity will achieve 10^(11)n/s with no radiation safety problems after the EAST NBITF shuts down.

关键词：剂量率测试设备停机 NBI 放射性核素激活中性束注入器试验设施

Performance of real‑time neutron/gamma discrimination methods

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Nuclear Science and Techniques 2023年第1期34卷 102-110页

作者： Shi‑Xing Liu Wei Zhang Zi‑Han Zhang Shuang Lin Hong‑Rui Cao Cheng‑Xin Song Jin‑Long Zhao guo‑qiang zhong School of Electronics Hefei University of TechnologyHefei 230009China China Nuclear Power Engineering Co. LtdBeijing 100840China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China

Nuclear security usually requires the simultaneous detection of neutrons and gamma *** the development of crystalline materials in recent years,Cs2LiLaBr6(CLLB)dual-readout detectors have attracted extensive attention from researchers,where real-time neutron/gamma pulse discrimination is the critical factor among detector performance *** study investigated the discrimination performance of the charge comparison,amplitude comparison,time comparison,and pulse gradient_(m)ethods and the effects of a Sallen–Key filter on their *** results show that the figure of merit(FOM)of all four methods is improved by proper *** them,the charge comparison method exhibits excellent noise resistance;moreover,it is the most_(s)uitable method of real-time discrimination for CLLB ***,its discrimination performance depends on the parameters t_(s),t_(m),and t_(e).When t_(s)corresponds to the moment at which the pulse is at 10%of its peak value,t_(e)requires a delay of only 640–740 ns compared to t_(s),at which time the potentially optimal FOM of the charge comparison method at 3.1–3.3 MeV is greater than *** FOM obtained using the t_(m)value calculated by a proposed maximized discrimination difference model(MDDM)and the potentially optimal FOM differ by less than 3.9%,indicating that the model can provide good guidance for parameter selection in the charge comparison method.

关键词： Charge comparison Maximized discrimination difference model Pulse filtering Real time n-γdiscrimination

Synthesis and antitumor evaluation of C3/C3 fluoroquinolone dimers(Ⅰ):Tethered with a fused heterocyclic s-triazolo[2,1-b][1,3,4]thiadiazole

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Chinese Chemical Letters 2010年第6期 661-663页

作者： guo qiang Hu~(a,*),zhong Quan Zhang~a,Song qiang Xie~a,Wen Long Huang~b a Institute of Chemistry & Biology,Henan University,Kaifeng 475001,China b China Pharmaceutical University,Nanjing 210009,China

Five C3/C3 fluoroquinolone dimers tethered with a fused heterocyclic ring of s-triazolo[2,1-b][1,3,4]thiadiazole derived from antibacterial quinoiones were synthesized and characterized,and their in vitro antitumor ac... 详细信息

关键词： Fluoroquinolone Dimer Antitumor evaluation

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms