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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

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Sensor data compression based on MapReduce

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 60-66页

作者： YU Yu guo zhong-wen Department of Computer Science and Engineer Ocean University of China

A compression algorithm is proposed in this paper for reducing the size of sensor data. By using a dictionary-based lossless compression algorithm, sensor data can be compressed efficiently and interpreted without decompressing. The correlation between redundancy of sensor data and compression ratio is explored. Further, a parallel compression algorithm based on MapReduce [1] is proposed. Meanwhile, data partitioner which plays an important role in performance of MapReduce application is discussed along with performance evaluation criteria proposed in this paper. Experiments demonstrate that random sampler is suitable for highly redundant sensor data and the proposed compression algorithms can compress those highly redundant sensor data efficiently.

关键词： data compression sensor data MapReduce surveillance application measurement system

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Study on the anti-inflammatory mechanism of moxibustion in rheumatoid arthritis in rats based on phospholipaseA2 signaling inhibition by Annexin 1

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Journal of Traditional Chinese Medicine 2024年第4期44卷 753-761页

作者： guo Yanding LUO Kun ZHANG Linlin LU Wenting SHANG Yanan zhong Yumei HU Danhui YANG Xin zhou Haiyan Department of Acupuncture-Moxibustion and Tuina the Third Affiliated HospitalChengdu University of Traditional Chinese MedicineChengdu 610075China External Treatment Center First People's Hospital of ChengduChengdu 610095China Department of Chengdu Integrated Traditional Chinese Medicine and Western Medicine Hospital Chengdu 610075China Department of Health Rehabilitation School Chengdu University of Traditional Chinese MedicineChengdu 610075China

OBJECTIVE:To determine whether moxibustion had an anti-inflammatory effect on rheumatoid arthritis(RA)by regulating Annexin 1 expression and interfering with the phospholipaseA2 signaling ***:Thirty male Sprague-Dawley rats were randomly categorized into five groups(six rats per group):blank control(CON)group,RA model(RA)group,moxibustion(MOX)group,Annexin 1 lentiviral intervention(RNAi-Anxa1)group,and Annexin 1 lentiviral intervention+moxibustion(RNAi-Anxa1+MOX)*** rats in the RNAi-Anxa1 and the RNAi-Anxa1+MOX groups were injected with the lentiviral vector-mediated RNAi-Anxa1 into the rat foot *** experimental RA rat model was established by injecting Freund's complete adjuvant(FCA)into the RA,MOX,RNAi-Anxa1,and RNAi-Anxa1+MOX *** in the MOX and RNAiAnxa1+MOX groups received moxibustion *** modeling,using moxibustion“Shenshu(BL23)”and“Zusanli(ST36)”,each point is 5 times,bilateral alternating,once a day,6 times for a course of treatment,between the courses of rest for a one day.A total of three treatment courses were *** bilateral pad thicknesses were measured using Vernier calipers on experimental days 1,7,14,21,and *** expression of cPLA2αsignaling in the synovium of diseased joints was observed using Western *** pathology of the rat ankle synovium was observed using hematoxylineosin(HE)***(IL)-1β,IL-10,prostaglandin E2(PGE2),and leukotriene B4(LTB4)were detected using enzyme-linked immunosorbent ***:Moxibustion increased the levels of Annexin 1 and decreased the inflammatory response in rats with *** increasing the expression of Annexin 1,the phosphorylated expression of cPLA2αwas inhibited,the serum levels of IL-1β,PGE2,and LTB4 decreased,and the level of IL-10 *** moxibustion treated RA rats after the Annexin 1 lentiviral intervention,the serum levels of IL-1β,PGE2,LTB4,and IL-10 were almost ***:Moxibustion enhanced the negative regulation of

关键词： annexins group IV phospholipases A2 signal transduction moxibustion arthritis,rheumatoid

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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

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Geochemical insights into contribution of petroleum hydrocarbons to the formation of hydrates in the Taixinan Basin, the South China Sea

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Geoscience Frontiers 2021年第6期12卷 394-403页

作者： Yan Li Yun-Xin Fang Qian-Zhi zhou Xiang-Po Xu Jin-zhong Liu guo-Yi zhou Jiang-Hai Wang Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering School of Marine SciencesSun Yat-Sen UniversityGuangzhou510006China Guangzhou Marine Geological Survey Guangzhou510760China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou510640China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519000China

Methane hydrate in the South China Sea (SCS) has extensively been considered to be biogenic on the basis of its δ13C andδD *** previous efforts have greatly been made,the contribution of thermogenic oil/gas has still been *** this study,biomarkers and porewater geochemical parameters in hydrate-free and hydrate-bearing sediments in the Taixinan Basin,the SCS have been measured for evaluating the contribution of petroleum hydrocarbons to the formation of hydrate deposits via a comparative study of their source inputs of organic matters,environmental conditions,and microbial *** results reveal the occurrence of C_(14)–C_(16) branched saturated fatty acids (bSFAs) with relatively high concentrations from sulfate-reducing bacteria(SRBs) in hydrate-bearing sediments in comparison with hydrate-free sediments,which is in accord with the positive δ^(13)C values of dissolved inorganic carbon (DIC),increasing methane concentrations,decreasing alkalinity,and concentration fluctuation of ions (Cl^(-),Br^(-),SO_(4)^(2-),Ca^(2+),and Mg^(2+)).These data indicate the relatively active microbial activities in hydrate-bearing sediments and coincident variations of environmental *** isotope compositions of b SFAs (-34.0‰to -21.2‰),n-alkanes (-34.5‰to-29.3‰),and methane(-70.7‰to -69.9‰) jointly demonstrate that SRBs might thrive on a different type of organic carbon rather than *** with numerous gas/oil reservoirs and hydrocarbon migration channels in the SCS,the occurrence of unresolved complex mixtures (UCMs),odd-even predominance (OEP) values (about 1.0),and biomarker patterns suggest that petroleum hydrocarbons from deep oil/gas reservoirs are the most probable carbon *** new results provide significant evidence that the deep oil/gas reservoirs may make a contribution to the formation of methane hydrate deposits in the SCS.

关键词： Petroleum hydrocarbons Sulfate-reducing bacteria(SRBs) Biomarkers Porewater geochemistry Gas hydrates The South China Sea(SCS)

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Gallery-templated Synthesis of Titanium/Silicon-containing Mesoporous Montmorillonite-based Catalytic Materials

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Chinese Chemical Letters 2003年第12期14卷 1285-1288页

作者： Chun Hui zhou zhong Hua GE Xiao Nian LI Hong Qiang guo Jian SUN College of Chemical Engineering Zhejiang University Of TechnologyHangzhou 310014

A mesoporous titanium/silicon -containing montmorillonite-based catalytic materials has been synthesized by novel gallery-templated techniques. XRD, SEM, framework IR, and N2 adsorptiondesorption isotherms provided evidence of the formation of Si/Ti pillars. The synthetic materials show potential catalytic application for hydroxylation of phenol with peroxide.

关键词： Mesoporous materials montmorillonite pillared clay hydroxylation of phenol.

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Research on the Performance of Titanium Gypsum Concrete Based on Calcium-Silicon-Sulfur Ratio

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Journal of Renewable Materials 2023年第1期11卷 423-434页

作者： Lixia guo Weikai Wang Ling zhong Yuhang guo School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou450046China Henan Water Valley Research Institute Zhengzhou450046China Henan Key Laboratory of Water Environment Simulation and Treatment Zhengzhou450002China

Based on the high sulfur content in titanium gypsum,the concept of the calcium-silicon-sulfur(Ca/Si/S)ratio was *** Ca/Si/S ratio of concrete was adjusted by changing the titanium gypsum,fly ash,and cement *** effects of different Ca/Si/S ratios on the mechanical properties,hydration products,and concrete micro-structure were investigated by nuclear magnetic resonance,uniaxial compression,and scanning electron *** result shows:(1)The compressive strength of concrete mixed with titanium gypsum increases first and then decreases with the Ca/Si/S ratio *** the Ca/Si/S ratio is 1:0.85:0.10,the strength reaches the peak and is lower than the blank group.(2)The microstructure indicates the addition of titanium gypsum can effectively stimulate the activity of fly ***,too much or too little titanium gypsum will hamper concrete strength development.(3)Titanium gypsum concrete’s nuclear magnetic resonance T2 spectrum has two characteristic *** the Ca/Si/S ratio decreasing,the micropores in the concrete expand towards the *** compressive strength is negatively correlated with the proportion of macropores and is positively correlated with the proportion of no-capillary pores.

关键词： Titanium gypsum calcium-silicon-sulfur ratio compressive strength pore structure

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Growth of N-polar GaN on vicinal sapphire substrate by metal organic chemical vapor deposition

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Rare Metals 2014年第6期33卷 709-713页

作者： Can-Tao zhong guo-Yi Zhang State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of Physics Peking University

The growth and properties of N-polar Ga N layers by metal organic chemical vapor deposition（MOCVD） were reported. It is found that N-polar Ga N grown on normal sapphire substrate shows hexagonal hillock surface morphology. With the misorientation angles increasing from 0.5° to 2.0° toward the a-plane of the sapphire substrate, the number of the hillock becomes less and less and finally the surface becomes flat one on the sapphire substrate with the misorientation angle of 2°. It is also found that the crystalline quality and the strain in the Ga N are greatly influenced by the misorientation angle.

关键词： GaN N-polarity Metal organic chemical vapor deposition

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Research with KNbO_(3) Bulk and Surface Properties Based on Density Functional Theory

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Chinese Physics Letters 2013年第2期30卷 186-189页

作者： SUN Hong-guo zhou zhong-Xiang YUAN Cheng-Xun YANG Xiao-Niu Polymer Composites Engineering Laboratory Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 Department of Physics Harbin Institute of TechnologyHarbin 150001

The geometrical structure optimization,band structure,density of states,and charge density contour of potassium niobate(KNbO_(3))in the bulk[100]direction and(100)surface are calculated and analyzed using density functional *** elastic constants,which can describe the bonding characteristics and structural stability,are also computed,and the dielectric function,which can be used to calculate all the other optical properties of the material,is *** density approximation functional analysis using CASTEP software is also *** similarities and differences are observed in the properties of the KNbO_(3) bulk and *** all of the calculated results for the bulk sample are twice those of the surface *** results are consistent with the experiment.

关键词： KNbO3 functional potassium

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An iterative algorithm for analysis of coupled structural-acoustic systems subject to random excitations

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Acta Mechanica Sinica 2012年第2期28卷 458-467页

作者： guo-zhong Zhao Gang Chen Zhan Kang State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology116024 DalianChina

This paper analyzes the random response of structural-acoustic coupled systems. Most existing works on coupled structural-acoustic analysis are limited to systems under deterministic excitations due to high computational cost required by a random response analysis. To reduce the computational burden involved in the coupled random analysis, an iterative procedure based on the Pseudo excitation method has been developed. It is found that this algorithm has an overwhelming advantage in computing efficiency over traditional methods, as demonstrated by some numerical examples given in this paper.

关键词： Random excitation Coupled structural-acoustic systems Pseudo excitation method

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