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Design and development of multi-channel front end electronics based on dual-polarity charge-to-digital converter for SiPM detector applications

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Nuclear Science and Techniques 2023年第2期34卷 1-12页

作者： yu‑Ying li chang‑yu li Kun Hu Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China

With the development of silicon photomultiplier(SiPM)technology,front-end electronics for SiPM signal processing have been highly sought after in various fields.A compact 64-channel front-end electronics(FEE)system achieved by fieldprogrammable gate array-based charge-to-digital converter(FPGA-QDC)technology was built and *** FEE consists of an analog board and FPGA *** analog board incorporates commercial amplifiers,resistors,and *** FPGA board is composed of a low-cost *** electronics performance of the FEE was evaluated in terms of noise,linearity,and uniformity.A positron emission tomography(PET)detector with three different readout configurations was designed to validate the readout capability of the FEE for SiPM-based *** PET detector was made of a 15×15 lutetium–yttrium oxyorthosilicate(LYSO)crystal array directly coupled with a SiPM array *** experimental results show that FEE can process dual-polarity charge signals from the SiPM *** addition,it shows a good energy resolution for 511-keV gamma photons under the dual-end readout for the LYSO crystal array irradiated by a Na-22 ***,the FEE based on FPGA-QDC shows promise for application in SiPM-based radiation detectors.

关键词： Readout electronics Charge measurement Radiation detector Silicon photomultiplier Field-programmable gate array

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高频副词“不停”的词汇化与语法化

江苏师范大学学报（哲学社会科学版） 2024年第3期50卷 43-50页

作者：于立昌徐慧江苏师范大学文学院江苏徐州221116

“不停”是现代汉语中表达动作行为反复发生的高频率副词,其由否定副词“不”和动词“停”在清代经过重新分析词汇化和语法化而来。这一词汇化和语法化的历程可概括为:在连动式结构中,“停”的动词性逐渐减弱,其后的谓词成分逐渐成为句... 详细信息

“不停”是现代汉语中表达动作行为反复发生的高频率副词,其由否定副词“不”和动词“停”在清代经过重新分析词汇化和语法化而来。这一词汇化和语法化的历程可概括为:在连动式结构中,“停”的动词性逐渐减弱,其后的谓词成分逐渐成为句子的语义重心,“不+停”在状语位置上逐渐词汇化,并语法化为高频副词。“不停”的词汇化与语法化机制与动因可概括为重新分析、句法语义基础、双音节韵律等。

关键词：不停频度副词词汇化语法化双音节韵律

Template-free synthesis of morphology- and size-controlled nano indium hydroxide

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1154-1161页

作者： chang-yu li Shou-xin liu College of Material Science and Engineering Northeast Forestry UniversityHarbin 150040China

Morphology-and size-controlled In（OH）3 nanocrystals were synthesized via a novel, low-cost and low-temperature （70°C） route in the absence of any template and surfactant. The as-prepared products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and high-resolution transmission electron microscopy （HRTEM） with selected area electron diffraction （SAED）. The morphology and size of In（OH）3 nanostructures can be controlled by adjusting the reaction conditions such as the reaction time, the concen-tration of the alkali, and the alkaline source. A possible mechanism for the evolution of the morphology- and size-controlled In（OH）3 was proposed. In addition, the optical properties of the In（OH）3 prepared by this method were studied by diffuse reflection spectra （DRS） and photoluminescence （PL） spectroscopy, and the results exhibit an obvious change of adsorption edges. The thermal behaviors of the as-prepared products were also explored by thermo-gravimetric （TG） and differential scanning calorimetry （DSC） measurements. According to the results of TG-DSC, the pure phase and uniformity of the In2O3 nanocube and nanorod can be obtained by annealing In（OH）3 precur-sors directly at 300°C.

关键词： indium hydroxide synthesis nanocrystals nanostructures morphology optical properties

Research on hydration of phenylacetylene assisted with additives in near-critical water

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Chinese Chemical Letters 2011年第4期22卷 393-396页

作者： Shuang li Yong Juan chang yu Wang li Yi Dai Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal UniversityShanghai 200062China

The hydration of phenylacetylene in near-critical water,assisted with additives（NaHSO4,ZnCl2,FeCl3）,has been successfully conducted with temperature and residence time ranges of 220-300℃and 60-180 min,*** results showed the catalytic ability is *** maximum yield of product acetophenone was 96.68%at 260℃,120 *** on the results found,a possible mechanism of hydration of phenylacetylene in near-critical water was proposed.

关键词： Hydration Phenylacetylene Additives Near-critical water Mechanism

Effect of flame conditions on abrasive wear performance of HVOF sprayed nanostructured WC-12Co coatings

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 72-76页

作者： WANG yu-yue li chang-jiu MA Jian YANG Guan-jun State Key Laboratory for Mechanical Behavior of Materials Xi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China State Key Laboratory for Mechanical Behavior of MaterialsXi''an Jiaotong University Xi''an 710049 China

Nanostructured WC-12Co coatings were deposited by high velocity oxy-fuel (HVOF) spraying with an agglomerated powder. The effect of flame conditions on the microstructure of the nanostructured coatings was investigated. The wear properties of the coatings were characterized using a dry rubber-wheel wear test. The results show that the nanostructured WC-Co coatings consist of WC, W2C, W and an amorphous binder phase. The microstructure of the coating is significantly influenced by the ratio of oxygen flow to fuel flow. Under the lower ratio of oxygen/fuel flow, the nanostructured coating presents a relative dense microstructure and severe decarburization of WC phase occurs during spraying. With increasing ratio of oxygen/fuel flow, the bonding of WC particles in the coating becomes loose resulting from the original structure of feedstock and the decarburization of WC becomes less owing to limited heating to the powder. Both the decarburization of WC particles in spraying and the bonding among WC particles in the coatings affect the wear performance. The examination of the worn surfaces of the nanostructured coatings reveals that the dominant wear mechanisms would be spalling from the interface of WCCo splats when spray particles undergo a limited melting. While the melting state of the spray particles is improved,the dominant wear mechanisms become the plastic deformation and plowing of the matrix and spalling of WC particles from the matrix.

关键词： high velocity oxy-fuel spraying nanostructure abrasive wear performance WC-Co coating

Cromakalin pretreatment affects mitochondrial structure and function in a rat model of ischemia/reperfusion injury

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Neural Regeneration Research 2008年第9期3卷 933-938页

作者： Shilei Wang Peng Wang Qingxian chang yu li Yan Jiang Shiduan Wang Department of Anesthesiology Affiliated Hospital of Qingdao University Medical College Qingdao 266003 Shandong Province China

BACKGROUND：Mitochondrial structural changes and energy dysmetabolism frequently occur subsequent to cerebral *** triphosphate（ATP）-sensitive potassium channel openers exhibit protective effects on cerebral ischemia/reperfusion ***：To validate the effects of cromakalin on mitochondrial structure and function in ischemic penumbra brain tissue in a rat model of middle cerebral artery occlusion（MCAO）.DESIGN,TIME AND SETTING：The present single-factor analysis of variance,randomized,controlled,animal experiment was performed at the Institute of Brain Science,Affiliated Hospital of Qingdao University Medical College between October 2007 and March ***：Forty male,Wistar rats were randomly divided into four groups,with 10 rats per group：sham-operated,MCAO,MCAO＋ATP-sensitive potassium channel opener（cromakalin）,and MCAO＋cromakalin＋ATP-sensitive potassium channel blocking agent（glibenclamide）.METHODS：Focal cerebral ischemia/reperfusion injury was induced by MCAO in all groups except the sham-operated *** MCAO cromakalin group was administered 10 mg/kg cromakalin（i.p.） prior to MCAO *** MCAO＋cromakalin＋glibenclamide group received an injection of 10 mg/kg cromakalin（i.v.）,and subsequently an injection of 10 mg/kg cromakalin（i.p.） prior to MCAO *** OUTCOME MEASURES：At 24 hours after cerebral ischemia/reperfusion injury,cellular apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate（dUTP） nick-end labeling *** C expression was measured by *** addition,mitochondrial swelling,membrane fluidity,membrane phospholipid and malonaldehyde（MDA） contents,as well as Na^＋-K^＋-ATPase,Ca^2 ＋-ATPase,and superoxide dismutase（SOD） activities were ***：Compared with the sham-operated group,the three ischemia groups exhibited significantly elevated mitochondrial MDA content,reduced membrane phospholipid and ATP contents,down-regulated membra

关键词： apoptosis cromakalin cytochrome C energy metabolism mitochondria potassium channel/opener

Neuroprotective effects of cromakalim on cerebral ischemia-reperfusion injury in rats Correlation with hippocampal metabotropic glutamate receptor 1 alpha and glutamate transporter 1

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Neural Regeneration Research 2010年第9期5卷 678-682页

作者： Shilei Wang Junchao liu Qingxian chang yu li, Yan Jiang Shiduan Wang Department of Anesthesiology Affiliated Hospital of Qingdao University Medical CollegeQingdao 266003Shandong ProvinceChina

BACKGROUND：Studies have reported that potassium channel openers exhibit a protective effect on cerebral ischemia-reperfusion injury and inhibit glutamate excitotoxicity in ***,the effects of the glutamate receptor 1α and glutamate transporter 1 remain poorly ***：To investigate the prophylactic use of the adenosine triphosphate-sensitive potassium channel opener cromakalim on neurological function and cerebral infarct size,as well as glutamate receptor 1α and glutamate transporter 1 expression,in rats with cerebral ischemia-reperfusion injury,and to explore action mechanisms underlying reduced glutamate excitotoxicity and neuroprotection in ***,TIME AND SETTING：Randomized,controlled,animal experiment was performed at the Brain Institute,Qingdao University Medical College,Between July 2008 and April ***：Cromakalim was purchased from Sigma,USA; rabbit anti-glutamate receptor 1α polyclonal antibody was offered by Wuhan Boster,China; rabbit anti-glutamate transporter 1 polyclonal antibody was offered by Santa Cruz Biotechnology,***：Sixty male,Wistar rats,aged 6 months,were randomly assigned to three groups （n =20）：sham-surgery,model,and *** thread methods were used to establish middle cerebral artery occlusion in rats from the model and cromakalim *** from the sham-surgery group were subjected to exposed common carotid artery,external carotid artery,and internal carotid artery,without *** （10 mg/kg） was administered 30 minutes prior to middle cerebral artery occlusion,but there was no intervention in the model and sham-surgery *** OUTCOME MEASURES：At 24 hours post-surgery,neurological behavioral functions were evaluated using Bederson＇s test,cerebral infarction volume was determined following tetrazolium chloride staining,and glutamate receptor 1a and glutamate transporter 1 expressions were detected using ***：Following cerebral ischemia-repe

关键词： cerebral ischemia-reperfusion cromakalim glutamate receptor 1α glutamate transporter 1

Formulation of Reduction Rate for Ultimate Compressive Strength of Stiffened Panel Induced by Opening

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China Ocean Engineering 2014年第4期28卷 557-568页

作者：于昌利 LEE Joo-sung School of Naval Architecture and Ocean Engineering Harbin Institute of Technology School of Naval Architecture and Ocean Engineering University of Ulsan

The main objective of this study is to numerically investigate the characteristics of ultimate compressive strength of stiffened panels with opening and also to fit the design-oriented formulae. For this purpose, three series of well executed experimental data on longitudinally stiffened steel plates with and without opening subjected to the uniform axial in-pane load which is carried out to study the buckling and post-buckling up to the final failure are chosen. Also, a nonlinear finite element method capable of efficiently analyzing the large elasto-plastic deflection behavior of stiffened panels is developed and used for simulation. The feasibility of the present simulation process is confirmed by a good agreement with the experimental results. More case studies are developed employing the simulation process to analyze the influence of various design variables on the reduction rate of ultimate strength of stiffened panel induced by opening. Based on the computed results, two design formulae are fitted and the accuracy of design formulae is studied. Furthermore, the viability of the design formulae for practical engineering is proved.

关键词： stiffened panel opening reduction rate non-linear analysis formulae fitting

Fourth-order phase-field modeling for brittle fracture in piezoelectric materials

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 837-856页

作者： yu TAN Fan PENG chang liU Daiming PENG Xiangyu li State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Science Chang'an UniversityXi'an 710064China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Failure analyses of piezoelectric structures and devices are of engineering and scientific *** this paper,a fourth-order phase-field fracture model for piezoelectric solids is developed based on the Hamilton *** typical electric boundary conditions are involved in the present model to characterize the fracture behaviors in various physical situations.A staggered algorithm is used to simulate the crack *** polynomial splines over hierarchical T-meshes(PHT-splines)are adopted as the basis function,which owns the *** numerical simulations are performed to study the influence of the electric boundary conditions and the applied electric field on the fracture behaviors of piezoelectric *** electric boundary conditions may influence crack paths and fracture loads *** present research may be helpful for the reliability evaluation of the piezoelectric structure in the future applications.

关键词： isogeometric analysis(IGA) brittle fracture fourth-order phase-field model piezoelectric solid