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Nuclear Science and Techniques 2019年第9期30卷 1-8页

作者： Xin-Yuan Zhao Feng liu Zhi Deng yi-nong liu The Department of Engineering Physics Tsinghua University Beijing 100084 China The Key Laboratory of Particle and Radiation Imaging (Tsinghua University) Ministry of Education Beijing 100084 China

The paper presents GEneral ReadOut (GERO), a general readout ASIC based on a switched capacitor array for micro-pattern gas detectors. It aims at providing general readout electronics for low-to-medium event-rate gas detectors with high sampling frequency, configurable storage depth, and data digitalization. The first prototype GERO chip integrates 16 channels and was fabricated using a 0.18-lm CMOS process. Each channel consists of a sampling array working in a ping-pong mode, a storage array with a 1024-cell depth, and 32 Wilkinson analog-todigital converters. The detailed design and test results are presented in the paper.

关键词： ASIC Switched capacitor array Waveform sampling Configurable deep memory depth

Cable coupling response in metal cavity under X-ray irradiation

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Nuclear Science and Techniques 2024年第10期35卷 110-120页

作者： Mao-Xing Zhang Lan-Feng Yuan Cui Meng yi-nong liu Department of Engineering Physics Tsinghua UniversityBeijing 100084China College of Electrical Engineering Zhejiang UniversityHangzhou 310007China Laboratory of Particle and Radiation Imaging Ministry of EducationBeijing 100084China

This study investigates the coupling response of cables inside a metal cavity under X-ray irradiation using the finite-difference time-domain method,particle simulation method,and transmission-line equation to solve the electromagnetic field inside the cavity and load voltage at the cable terminal under X-ray *** results show that under a strong ionizing radiation environment of 1 J/cm^(2),a strong electromagnetic environment is generated inside the *** cable shielding layer terminal couples a voltage of 15.32 V,whereas the core wire terminal couples a voltage of 0.31 *** strong X-ray irradiation,the metal cavity not only fails to provide electromagnetic shielding,but also introduces new electromagnetic *** study also provides a method for reducing the number of emitted electrons by adding low-Z materials,which can effectively reduce the coupled electric field and voltage.

关键词： Ionizing radiation Metal cavity System-generated electromagnetic pulse Transmission-line model

Offset-free DC-coupled analog frontend circuit for high-dynamicrange signals

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Nuclear Science and Techniques 2020年第4期31卷 29-36页

作者： Ya-Fei Du Jun Wu Chen Yuan Chuan-Fei Zhang yi-nong liu Department of Engineering Physics Tsinghua UniversityBeijing 100084China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The analog frontend(AFE)coupling circuit is a crucial processing element for data acquisition systems based on analog-to-digital converters(ADCs).Currently,high-speed and high-resolution ADCs are predominantly designed with differential input *** highspeed ADC drivers are mainly AC-coupled by employing transformers(Baluns)or fully differential amplifiers(FDAs)with blocking ***,the results of this study indicate that a certain degree of DC offset error exists and manifests itself as the baseline error in the presence of power dividers connecting several DC-coupled channels that implement high-dynamic-range(HDR)signal *** study involves a theoretical analysis and explanation of the baseline offset *** offset error can potentially lead to unexpected out-of-range issues for sampling devices,including high-speed ADCs and switched capacitor array ***-performance FDAs are adopted,and an offset-free DC-coupled AFE circuit is proposed to address the aforementioned issue using twostage amplification and a resistive *** proposed methodology is verified via circuit simulations and hardware ***,the baseline offset problem can be accurately solved using the proposed circuit by minimizing the neglectable *** proposed circuit facilitates improvements in the high-precision measurement of HDR signals in many nuclear physics experiments and some applications in the DC-coupling scheme with FDAs involving resistive power dividers.

关键词： Offset-free DC-coupled Two-stage amplification Resistive attenuator High-dynamic-range

In-situ synchrotron high energy X-ray diffraction study of spontaneous reorientation of R phase upon cooling in nanocrystalline Ti_(50)Ni_(45.5)Fe_(4.5)alloy

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Rare Metals 2022年第6期41卷 1948-1954页

作者： Zhi-Yuan Ma Yu-Xuan Chen Yang Ren Kai-Yuan Yu Da-Qiang Jiang yi-nong liu Li-Shan Cui Department of Materials Science and Engineering China University of Petroleum(Beijing)Beijing 102249China Department of Physics City University of Hong KongHong Kong 999077China Centre for Neutron Scattering City University of Hong KongHong Kong 999077China Department of Mechanical Engineering The University of Western AustraliaPerthWA 6009Australia

This study investigated a peculiar phenomenon of self-reorientation of thermally formed R phase in nanocrystalline Ti_(50)Ni_(45.5)Fe_(4.5)by means of in-situ syn-chrotron high energy X-ray diffraction(HE-XRD).Two samples with different average grain sizes of 40 and 90 nm were investigated.R phase in the 40-nm grain size sample was found to self-reorient gradually upon cooling,whereas the same phenomenon did not occur in the 90-nm grain size *** self-reorientation process is attributed to the development and evolution of an internal stress anisotropy caused by the second order continuous lattice distortion of R phase upon further cooling in the small nanograined matrix,which lacks the self-accommodation mechanism for internal stress cancellation.

关键词： TiNiFe Martensitic transformation R phase reorientation Synchrotron diffraction Nanocrystalline material

Design and offline processing of an ultrafast digitizer based on internal cascaded DRS4

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Nuclear Science and Techniques 2019年第8期30卷 35-41页

作者： Ya-Fei Du Jun Wu Chen Yuan Bo Yang Cen-Ming Ye Chuan-Fei Zhang yi-nong liu Department of Engineering Physics Tsinghua UniversityBeijing 100084China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621999China

In this paper, we present an ultrafast digitizer utilizing the DRS4 switched capacitor array applicationspecific integrated circuit to achieve an ultrafast sampling speed of at most 5 GS/s. We cascaded all eight channels(sub-channels) of a single DRS4 chip for increased storage depth. The digitizer contains four DRS4 chips, a quadchannel analog-to-digital converter,a controlling fieldprogrammable gate array, a PXI interface, and an SFP+connector. Consequently, each DRS4 channel has a depth of 8192 points and a vertical resolution of 14 bits. The readout sequences should be broken into several segments and then reordered to obtain the correct sequential data sets, and this offline procedure varies in different readout modes. This paper describes the design and implementation of the hardware;in particular, the respective processing procedures are described in detail. Furthermore, the offset error is calibrated and corrected to improve the precision of the captured waveform in both single-channel and highresolution modes.

关键词： Ultrafast Digitizer DRS4 Cascade Readout

Corrosion behavior of electrodeposited Ni with normal and bimodal grain size distribution

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Transactions of Nonferrous Metals Society of China 2019年第2期29卷 424-436页

作者： Feng YANG Xiao-feng ZHANG Hong YANG yi-nong liu Shi-jie HAO Li-shan CUI State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249China Beijing Key Laboratory of Failure Corrosion and Protection of Oil/Gas Facility MaterialsChina University of Petroleum-BeijingBeijing 102249China

The corrosion behavior of electrodeposited Ni with normal and bimodal grain size distribution was *** microstructure of samples was researched by SEM,EBSD,TEM and *** corrosion behavior was studied by potentiodynamic tests and electrochemical *** Ni with(100)and(111)textures was prepared by an electrodeposition *** Ni samples with different grain size distributions and twins were then obtained by heat treatment of nanocrystalline Ni at different *** effect of grain size on corrosion behavior of the sample depends on the ability of the environment to *** the case where passive film forms on the sample surface,the corrosion resistance of the sample increases with decreasing grain ***,the corrosion resistance decreases with decreasing grain size when there is no *** corrosion behavior of samples with bimodal grain size distribution obeys the rule of mixture.

关键词： corrosion behavior electrodeposited Ni bimodal grain twin grain size

Seismic isolation design and resilience improvement of railway station considering the influence of near-fault pulse-like ground motions

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 257-270页

作者： Pan yi Song Jiayu Chen Qi liu Yongxin School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Seismic Engineering of Sichuan Province Chengdu 610031China

To improve the resilience of railway stations,a typical station was selected as the research object,and an isolation design was ***-four groups of near-fault pulse-like ground motions were *** seismic resilience of the no-isolation railway stations(NIRS)and the isolation railway stations(IRS)were compared to provide a numerical result of the improvement in *** results show that in the station isolation design,the station's functional requirements and structural characteristics should be considered and the appropriate placement of isolation bearings is under the waiting *** the action of a rare earthquake,the repair cost,repair time,rate of harm and death of the IRS were decreased by 8.04 million,18.30 days,6.93×10^(-3)and 1.21×10^(-3),respectively,when compared to the *** IRS received a seismic resilience grade of three-stars and the NIRS only one-star,indicating that rational isolation design improves the seismic resilience of ***,for the design of stations close to earthquake faults,it is suggested to utilize appropriate isolation techniques to improve their seismic resilience.

关键词： railway station near-fault pulse-like ground motion isolation design seismic resilience resilience improvement

Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-F18

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Earth and Planetary Physics 2025年第1期9卷 137-147页

作者： yi liu JiuHou Lei FuQing Huang Su Zhou School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Science Guiyang UniversityGuiyang 550005China

Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)*** data was obtained at an altitude of around 860 km in near polar orbit,throughout *** study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude *** differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron *** our study,the troughs exhibited a higher occurrence rate in local winter than in summer,and extended to lower latitudes with increasing geomagnetic *** was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct ***,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in *** ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E ***,the troughs related to ion temperature(Ti)maximums were observed at relatively higher latitudes,occurring more frequently in *** addition,the troughs related to ion velocity(Vi)maximums could be observed in all *** troughs with the maximum-Ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both *** implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resulting in a density depletion within the trough region.

关键词： topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum

Constrained Networked Predictive Control for Nonlinear Systems Using a High-Order Fully Actuated System Approach

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 478-480页

作者： yi Huang Guo-Ping liu yi Yu Wenshan Hu the School of Electrical Engineering and Automation Wuhan University IEEE the Center for Control Science and Technology Southern University of Science and Technology the Department of Electrical and Electronic Engineering The Hong Kong Polytechnic University

Dear Editor,In this letter, a constrained networked predictive control strategy is proposed for the optimal control problem of complex nonlinear highorder fully actuated (HOFA) systems with noises. The method can effectively deal with nonlinearities, constraints, and noises in the system, optimize the performance metric, and present an upper bound on the stable output of the system.

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Tanreqing Injection Inhibits Activation of NLRP3 Inflammasome in Macrophages Infected with Influenza A Virus by Promoting Mitophagy

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Chinese Journal of Integrative Medicine 2025年第1期31卷 19-27页

作者： liu Tian-yi HAO Yu MAO Qin ZHOU Na liu Meng-hua WU Jun WANG yi YANG Ming-rui School of Life Sciences Beijing University of Chinese MedicineBeijing102488China Experimental Research Center China Academy of Chinese Medical SciencesBeijing100700China

Objective: To investigate the inhibitory effect of Tanreqing Injection(TRQ) on the activation of nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3(NLRP3) inflammasome in macrophages infected with influenza A virus and the underlying mechanism based on mitophagy pathway. Methods:The inflammatory model of murine macrophage J774A.1 induced by influenza A virus [strain A/Puerto Rico/8/1934(H1N1), PR8] was constructed and treated by TRQ, while the mitochondria-targeted antioxidant Mito-TEMPO and autophagy specific inhibitor 3-methyladenine(3-MA) were used as controls to intensively study the anti-inflammatory mechanism of TRQ based on mitophagy-mitochondrial reactive oxygen species(mt ROS)-NLRP3 inflammasome pathway. The levels of NLRP3, Caspase-1 p20, microtubule-associated protein 1 light chain 3 Ⅱ(LC3Ⅱ) and P62 proteins were measured by Western blot. The release of interleukin-1β(IL-1β) was tested by enzyme linked immunosorbent assay, the mt ROS level was detected by flow cytometry, and the immunofluorescence and co-localization of LC3 and mitochondria were observed under confocal laser scanning microscopy. Results: Similar to the effect of Mito-TEMPO and contrary to the results of 3-MA treatment, TRQ could significantly reduce the expressions of NLRP3, Caspase-1 p20, and autophagy adaptor P62, promote the expression of autophagy marker LC3Ⅱ, enhance the mitochondrial fluorescence intensity, and inhibit the release of mt ROS and IL-1β(all P<0.01).Moreover, LC3 was co-localized with mitochondria, confirming the type of mitophagy. Conclusion: TRQ could reduce the level of mt ROS by promoting mitophagy in macrophages infected with influenza A virus, thus inhibiting the activation of NLRP3 inflammasome and the release of IL-1β, and attenuating the inflammatory response.

关键词： Tanreqing Injection influenza virus anti-inflammation mitophagy nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 inflammasome Chinese medicine