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A QTC-based signal readout for position-sensitive multi-output detectors

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Nuclear Science and Techniques 2016年第5期27卷 208-214页

作者： Wei Zhou zhi-ming zhang Dao-Wu Li Pei-Lin Wang Bao-Tong Feng Xian-Chao Huang ting-ting Hu xiao-Hui Li Yan Chen ying-Jie Wang Yan-Tao liu yi-Wen zhang Shi-Feng Sun xiao-Yue Gu ming-Jie Yang Xiong xiao long Wei Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Beijing Engineering Research Center of Radiographic Techniques and Equipment Beijing 100049 China University of Chinese Academy of Sciences Beijing 100049

A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circuit and charge-to-time conversion(QTC) *** 64 outputs of a Hamamatsu H8500 position-sensitive photomultiplier tube were processed,and three digital pulses were *** widths of digital pulses were determined using the time-to-digital converter in an field programmable gate *** energy and position information of incident y-rays is estimated based on the proportionality between the width of digital pulses and input charge created by y-photons.A prototype was built using discrete components and tested,and the energy and position resolutions were improved compared with that obtained with standard *** method greatly simplifies the front-end electronics and the digital *** enables a compact electronics system and an easy integration into an ASIC.

关键词：输出信号位置灵敏探测器多输出读出位置灵敏光电倍增管现场可编程门阵列时间-数字转换器位置敏感探测器

Study on the influence of projectile on muzzle disturbance

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Defence Technology（防务技术） 2018年第5期14卷 570-577页

作者： Fei-fei liu Yan-ming Song Hai-long Yu Wen-ding Lin Jie zhang zhi-hui Si ming-kang Ding xiao-ting Rui China Weapon Industry Corporation NHIC Nanjing Research Institute Nanjing210000China China Weapon Industry Corporation NHIC Baotou014000China Institute of Launch Dynamics Nanjing University of Science&TechnologyNanjing210094China

In order to make an efficient analysis of muzzle disturbance influenced by projectile mass, mass eccentricity, dynamic unbalance, load deviation, and clearance between projectile and bore, the orthogonal test method is extended to analyze the launch dynamics. Taking a tank as the research object, the launch dynamics equations of a tank system are established. Based on the stochastic simulation principle, the tank launch dynamic simulation system is constructed and through the development of the orthogonal test method, the influence of projectile on muzzle disturbance is studied. The study results provided both theoretical foundation and simulation approaches for improving the firing dispersion of the tank.

关键词： Muzzle disturbance Orthogonal test Projectile-barrel coupling Firing dispersion

Energy correction based on fluorescence attenuation of DAMPE

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Research in Astronomy and Astrophysics 2020年第8期20卷 163-168页

作者： Li-Bo Wu Yun-long zhang zhi-Yong zhang yi-Feng Wei Si-Cheng Wen Hao-ting Dai Cheng-ming liu xiao-Lian Wang Zi-Zong Xu Guang-Shun Huang State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

The major scientific goals of the DArk Matter Particle Explorer(DAMPE)are to study cosmicray electrons(including positrons)and gamma rays from 5 GeV to 10 TeV and nuclei from Z=1 to 26 up to 100 *** deposited energy measured by the Bismuth Germanate Oxide(BGO)calorimeter of DAMPE is affected by fluorescence attenuation in BGO crystals that are 600 mm *** this work,an in-orbit attenuation calibration method is reported,and energy correction of the sensitive detector unit of the BGO calorimeter is also presented.

关键词： DAMPE BGO calorimeter fluorescence attenuation dark matter

Sexual,physical and overall adverse effects in patients treated with 5a-reductase inhibitors:a systematic review and meta-analysis

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Asian Journal of Andrology 2022年第4期24卷 390-397页

作者： Jun-Jie zhang xiao Shi ting Wu Meng-Da zhang Jin Tang Guang-ming yin zhi long Le-Ye He Lin Qi long Wang Department of Urology The Third Xiangya HospitalCentral South UniversityChangsha 410008China Department of Urology Xiangya HospitalCentral South UniversityChangsha 410013China Department of Gastroenterology The Third Xiangya HospitalCentral South UniversityChangsha 410013China Department of Cardiovascular Medicine The Third Xiangya HospitalCentral South UniversityChangsha 410013China

Postfinasteride syndrome(PFS)is a term coined to characterize a constellation of reported undesirable sexual,physical,and neuropsychiatric side *** the present study,we conducted the meta-analysis to demonstrate whether the use of 5α-reductase inhibitors(5ARIs)increases the risk of PFS-like adverse effects.A search of studies published until May 10,2020,was performed using PubMed,EMBASE,and the Cochrane *** included randomized controlled trials with at least one comparison between male patients receiving 5ARIs versus placebo for the treatment of benign prostatic hyperplasia(BPH)or androgenetic alopecia(AGA),and identified 34 studies from 28 articles that met our eligibility *** the random-effects model,the overall use of 5ARIs exhibited a 1.87-fold risk of PFS-like adverse effects during the trial(95%confidence interval[CI]:1.64-2.14).Regarding specific types of adverse effects,the use of 5ARIs had a 1.89-fold risk of sexual adverse effects(95%CI:1.74-2.05)and was associated with an increased risk of physical adverse effects(relative risk[RR]:1.31,95%CI:0.80-2.15),albeit without statistical *** meta-analysis helped to better define the adverse effects caused by *** concluded that the overall use of 5ARIs significantly increased the risk of PFS-like adverse effects in men with AGA or BPH during *** awareness of and education on the PFS-like adverse effects are necessary for clinicians.

关键词： 5α-reductase inhibitors adverse effects androgenetic alopecia benign prostatic hyperplasia postfinasteride syndrome

Fecal microbiota transplantation cured epilepsy in a case with Crohn's disease: The first report

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World Journal of Gastroenterology 2017年第19期23卷 3565-3568页

作者： zhi He Bo-Ta cui ting zhang Pan Li Chu-Yan long Guo-Zhong Ji Fa-ming zhang Medical Center for Digestive Diseases The Second Affiliated Hospital of Nanjing Medical University Key Lab of Holistic Integrative Enterology Nanjing Medical University

Fecal microbiota transplantation(FMT)is a promising strategy that involves reconstruction of gut ***,it has been considered as a treatment of Crohn’s disease(CD)and certain neurological ***,to the best of our knowledge,we report the first case that used FMT to achieve remission of intestinal and neurological symptoms in a girl with CD and a 17-year history of *** the 20 mo of follow-up,FMT has proved its efficacy in preventing relapse of seizures after withdrawing the antiepileptic ***,this finding highlights the role of microbiota-gut-brain axis and inspires a novel treatment for epilepsy through remodeling gut microbiota.

关键词： Fecal microbiota transplantation Epilepsy Crohn's disease Gut microbiota Brain-gut axis

Investigation on the temperature distribution and strength of flat steel ribbon wound cryogenic high-pressure vessel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 210-215页

作者： cui xiao-long CHEN Guang-ming Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

By analyzing heat transfer on the wall of fiat steel ribbon wound vessel （FSRWV）, a numerical model of temperature distribution on the entire wall （including inner core wall, flat steel ribbons, outside cylinder of jacket and insulating layer） was established by the authors. With the model, the temperature distribution and the length change in the vessel walls and flat steel ribbons in low temperature are calculated and analyzed. The results show that the flat steel ribbon wound cryogenic high-pressure vessel is simpler in structure, safer and easier to manufacture than those of conventional ones.

关键词： Cryogenic high-pressure vessel Flat steel ribbon wound vessel (FSRWV) Temperature distribution Numerical simulation

Tunable topological quantum states in three- and two-dimensional materials

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Frontiers of physics 2015年第2期10卷 41-56页

作者： ming Yang xiao-long zhang Wu-ming liu Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We review our theoretical advances in tunable topological quantum states in three- and two- dimensional materials with strong spin-orbital couplings. In three-dimensional systems, we propose a new tunable topological insulator, bismuth-based skutterudites in which topological insulating states can be induced by external strains. The orbitals involved in the topological band-inversion process are the d- and p-orbitals, unlike typical topological insulators such as Bi=Sea and BiTeI, where only the p-orbitals are involved in the band-inversion process. Owing to the presence of large d-electronic states, the electronic interaction in our proposed topological insulator is much stronger than that in other conventional topological insulators. In two-dimensional systems, we in- vestigated 3d-transition-metal-doped silicene. Using both an analytical model and first-principles Wannier interpolation, we demonstrate that silicene decorated with certain 3d transition metals such as vanadium can sustain a stable quantum anomalous Hall effect. We also predict that the quantum valley Hall effect and electrically tunable topological states could be realized in certain transition-metal-doped silicenes where the energy band inversion occurs. These findings provide realistic materials in which topological states could be arbitrarily controlled.

关键词： first-principles calculations topological insulator quantum anomalous Hall effect

Fast pulse sampling module for real-time neutron–gamma discrimination

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Nuclear Science and Techniques 2019年第5期30卷 130-137页

作者： Jia-Le Cai Dao-Wu Li Pei-Lin Wang zhi-ming zhang xiao-Hui Li Bao-Tong Feng ting-ting Hu Teng Tong Wei Zhou long Wei Beijing Engineering Research Center of Radiographic Techniques and Equipment Institute of High Energy PhysicsChinese Academy of Sciences School of Nuclear Science and Technology University of Chinese Academy of Sciences

An adaptable and compact fast pulse sampling module was developed for the neutron–gamma discrimination. The developed module is well suited for low-cost and low-power consumption applications. It is based on the Domino Ring Sampler 4(DRS4) chip, which offers fast sampling speeds up to 5.12 giga samples per second(GSPS) to digitize pulses from front-end detectors. The high-resolution GSPS data is useful for obtaining precise real-time neutron–gamma discrimination results directly in this module. In this study, we have implemented real-time data analysis in a field programmable gate array. Real-time data analysis involves two aspects: digital waveform integral and digital pulse shape discrimination(PSD). It can significantly reduce the system dead time and data rate processed offline. Plastic scintillators(EJ-299-33), which have proven capable of PSD, were adopted as neutron detectors in the experiments. A photomultiplier tube(PMT)(model #XP2020) was coupled to one end of a detector to collect the output light from it. The pulse output from the anode of the PMT was directly passed onto the fast sampling module. The fast pulse sampling module was operated at 1 GSPS and 2 GSPS in these experiments, and the AmBe-241 source was used to examine the neutron–gamma discrimination quality. The PSD results with different sampling rates and energy thresholds were evaluated. The figure of merit(FOM) was used to describe the neutron–gamma discrimination quality. The best FOM value of 0.91 was obtained at 2 GSPS and 1 GSPS sampling rates with an energy threshold of 1.5 MeV_(ee)(electron equivalent).

关键词： Real time Neutron–gamma discrimination Domino Ring Sampler 4 Plastic scintillators

Investigation of shale gas microflow with the Lattice Boltzmann method

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Petroleum Science 2015年第1期12卷 96-103页

作者： xiao-Ling zhang Li-zhi xiao long Guo Qing-ming Xie State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Key Laboratory of Shale Gas Exploration Ministry of Land and Resources Chongqing Institute of Geology and Mineral Resources

In contrast to conventional gas-bearing rocks, gas shale has extremely low permeability due to its nano- scale pore networks. Organic matter which is dispersed in the shale matrix makes gas flow characteristics more complex. The traditional Darcy＇s law is unable to estimate matrix permeability due to the particular flow mechanisms of shale gas. Transport mechanisms and influence factors are studied to describe gas transport in extremely tight shale. Then Lattice Boltzmann simulation is used to establish a way to estimate the matrix permeability numerically. The results show that net desorption, diffu- sion, and slip flow are very sensitive to the pore scale. Pore pressure also plays an important role in mass fluxes of gas. Temperature variations only cause small changes in mass fluxes. The Lattice Boltzmann method can be used to study the flow field in the micropore spaces and then provides numerical solutions even in complex pore structure models. Understanding the transport characteristics and establishing a way to estimate potential gas flow is very important to guide shale gas t＇eserve estimation and recovery schemes.

关键词： Shale gas Permeability Adsorption Desorption Diffusion Slip effect