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A new digital pulse processing method for 2πa and 2πb emitter measurement

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Nuclear Science and Techniques 2016年第6期27卷 137-143页

作者： zheng Tu ke-Zhu Song Ming Zhang zhi-Jie Yang zhi-Guo Ding Hong-Wei Yu Jun-Cheng Liang Hao-Ran Liu State key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China National Institute of Metrology 18 North Third Ring EastRd.Beijing 100029China

Digital pulse processing has developed rapidly during recent ***,it has been widely applied in many *** this study,we introduce a digital pulse processing method for 2πa and 2πb emitter *** digital pulse processing method for 2πa and 2πb emitter measurement is comprised of a field-programmable gate-array-based acquisition card and a pulse-height analysis *** established two channels(one for the a emitter and one for the b emitter) on an acquisition board using an analog-to-digital converter with a 16-bit resolution at a speed of 100 million samples per *** this study,we used captured and stored data to analyze emission rate counts and *** method we established takes into account noise cancelation,dead-time correction,background subtraction,and zero-energy *** carefully designed control procedures in order to simplify pulse-width fitting and threshold-level *** transmitted data and commands through a universal serial bus between the acquisition board and the *** results of our tests prove that our method performs well in pulse reconstruction fidelity and amplitude measurement *** with the current standard method for measuring 2πa and 2πb emission rates,our system demonstrates excellent precision in emission rate counting.

关键词：脉冲处理测量性能发射器顺序控制程序 π 数据采集卡测量精度模数转换器

Effect of CO_2 and H_2O on gasification dissolution and deep reaction of coke

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1402-1411页

作者： zhi-yu Chang Ping Wang Jian-liang Zhang ke-xin Jiao Yue-qiang Zhang zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology Beijing School of Metallurgical Engineering Anhui University of Technology The third ironworks Ma'anshan Iron & Steel Co. Ltd

To more comprehensively analyze the effect of CO_2 and H_2O on the gasification dissolution reaction and deep reaction of coke, the reactions of coke with CO_2 and H_2O using high temperature gas–solid reaction apparatus over the range of 950–1250°C were studied, and the thermodynamic and kinetic analyses were also performed. The results show that the average reaction rate of coke with H_2O is about 1.3–6.5 times that with CO_2 in the experimental temperature range. At the same temperature, the endothermic effect of coke with H_2O is less than that with CO_2. As the pressure increases, the gasification dissolution reaction of coke shifts to the high-temperature zone. The use of hydrogen-rich fuels is conducive to decreasing the energy consumed inside the blast furnace, and a corresponding high-pressure operation will help to suppress the gasification dissolution reaction of coke and reduce its deterioration. The interfacial chemical reaction is the main rate-limiting step over the experimental temperature range. The activation energies of the reaction of coke with CO_2 and H_2O are 169.23 kJ ·mol-1 and 87.13 kJ·mol^(-1), respectively. Additionally, water vapor is more likely to diffuse into the coke interior at a lower temperature and thus aggravates the deterioration of coke in the middle upper part of blast furnace.

关键词： coke gasification dissolution reaction deep reaction rate-limiting step activation energy

The Role of Exportin-5 in MicroRNA Biogenesis and Cancer

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Genomics, Proteomics & Bioinformatics 2018年第2期16卷 120-126页

作者： ke Wu Juan He Wenchen pu Yong Peng Department of Thoracic Surgery State Key Laboratory of Biotherapy West China Hospital Sichuan University

MicroRNAs （miRNAs） are conserved small non-coding RNAs that play an important role in the regulation of gene expression and participate in a variety of biological processes. The biogenesis of miRNAs is tightly controlled at multiple steps, such as transcription of miRNA genes, processing by Drosha and Dicer, and transportation of precursor miRNAs （pre-miRNAs） from the nucleus to the cytoplasm by exportin-5 （XPO5）. Given the critical role of nuclear export of premiRNAs in miRNA biogenesis, any alterations of XPO5, resulting from either genetic mutation, epigenetic change, abnormal expression level or posttranslational modification, could affect miRNA expression and thus have profound effects on tumorigenesis. Importantly, XPO5 phosphorylation by ERK kinase and its cis/trans isomerization by the prolyl isomerase Pinl impair XPO5＇s nucleo-to-cytoplasmic transport ability of pre-miRNAs, leading to downregulation of mature miRNAs in hepatocellular carcinoma. In this review, we focus on how XPO5 transports pre-miRNAs in the cells and summarize the dysregnlation of XPO5 in human tumors.

关键词： Exportin-5 MicroRNA Biogenesis Dysregulation Cancer

Spatial pattern of impervious surfaces and their impacts on land surface temperature in Beijing,China

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Journal of Environmental Sciences 2007年第2期19卷 250-256页

作者： XIAO Rong-bo OUYANG zhi-yun zheng Hua LI Wei-feng SCHIENke Erich W WANG Xiao-ke State key Lab of Urban and Regional Ecology Environmental Sciences Chinese Academy of Sciences Belting 100085 China Department of Science and Technology Studies Rensselaer Polytechnic Institute Troy NY 12180 USA

Land surface temperature （LST）, which is heavily influenced by urban surface structures, is a significant parameter in urban environmental analysis. This study examined the effect impervious surfaces （IS） spatial patterns have on LST in Beijing, China. A classification and regression tree model （CART） was adopted to estimate IS as a continuous variable using Landsat images from two seasons combined with QuickBird. LST was retrieved from the Landsat Thematic Mapper （TM） image to examine the relationships between IS and LST. The results revealed that CART was capable of consistently predicting LST with acceptable accuracy （correlation coefficient of 0.94 and the average error of 8.59%）. Spatial patterns of IS exhibited changing gradients across the various urban-rural transects, with LST values showing a concentric shape that increased as you moved from the outskirts towards the downtown areas. Transect analysis also indicated that the changes in both IS and LST patterns were similar at various resolution levels, which suggests a distinct linear relationship between them. Results of correlation analysis further showed that IS tended to be positively correlated with LST, and that the correlation coefficients increased from 0.807 to 0.925 with increases in IS pixel size. The findings identified in this study provide a theoretical basis for improving urban planning efforts to lessen urban temperatures and thus dampen urban heat island effects.

关键词： urban heat islands urban land cover normalized difference vegetation index (NDVI) climate mitigation regression tree

Coordinated Control of Multi-Agent Systems with a Varying-Velocity Leader and Input Saturation

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Communications in Theoretical Physics 2009年第9期52卷 449-456页

作者： PENG ke SU Hou-Sheng YANG Yu-pu Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

In this paper,we investigate a leader-following tracking problem for multi-agent systems with *** propose a distributed bounded protocol for each follower to track a leader whose states may not be *** theoretically prove that each agent can follow the leader with estimable track ***,somenumerical simulations are presented to illustrate our theoretical results.

关键词： consensus coordinated control multi-agent system networked system input saturation switching topology

Exactly Solved Anderson Lattice Model

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Chinese Physics Letters 1996年第3期13卷 207-210页

作者： LIU Wu-ming ZHAO Hong-wei pu Fu-ke Institute of Physics Chinese Academy of SciencesBeijing 100080 Institute of Theoretical Physics Shanxi UniversityTaiyuan 030006 International Center for Materials Physics Chinese Academy of SciencesShenyang 110015 Department of Physics Tsinghua UniversityBeijing 100084 CCAST(World Laboratory) PO.Box 8730Beijing 100080

A solvable Anderson lattice model is *** exact eigenstates of model Hamiltonian are constructed by using the Bethe *** Be the ansatz equations are obtained from the periodic boundary conditions.

关键词： conditions Hamiltonian exact

Blocking meningeal lymphatic drainage aggravates Parkinson’s disease-like pathology in mice overexpressing mutated α-synuclein

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Translational Neurodegeneration 2019年第1期8卷 77-93页

作者： Wenyan Zou Tinglin pu Weixi Feng Ming Lu Ying zheng Renhong Du Ming Xiao gang Hu Department of Pharmacology School of Medicine and Life SciencesNanjing University of Chinese Medicine138 Xianlin AvenueNanjing 210023JiangsuChina Jiangsu key Laboratory of Neurodegeneratiion Department of PharmacologyNanjing Medical University101 Longmian AvenueNanjing 211166JiangsuChina

Background:Abnormal aggregation of brainα-synuclein is a central step in the pathogenesis of Parkinson’s disease(PD),thus,it is reliable to promote the clearance ofα-synuclein to prevent and treat *** studies have revealed an essential role of glymphatic system and meningeal lymphatic vessels in the clearance of brain macromolecules,however,their pathophysiological aspects remain ***:Meningeal lymphatic drainage of 18-week-old A53T mice was blocked via ligating the deep cervical lymph *** weeks later,glymphatic functions and PD-like phenotypes were systemically ***:Glymphatic influx of cerebrospinal fluid tracer was reduced in A53T mice,accompanied with perivascular aggregation ofα-synuclein and impaired polarization of aquaporin 4 expression in substantia *** lymphatic ligation aggravated glymphatic dysfunction of A53T mice,causing more severe accumulation ofα-synuclein,glial activation,inflammation,dopaminergic neuronal loss and motor ***:The results suggest that brain lymphatic clearance dysfunction may be an aggravating factor in PD pathology.

关键词： A53T transgenic mice α-Synuclein Glymphatic clearance Neurodegeneration Parkinson’s disease

INVESTIGATION　ON　THE　PHASE　DIAGRAM　OF　TERNARY　SYSTEM　LaCl_3-SrCl_2-LiCl

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Chinese Chemical Letters 1996年第5期7卷 483-486页

作者： Chao Gui zheng Yan ke zheng Department of Chemistry Peking University Beijing 100871

Abstract: The phase diagram of ternary system LaCl3 - SrCl2 - LiCl has been investigated by means of DTA. It was found that there were three fields corresponding to primary crystallization of LaCl3, SrCl2 and LiCl respectively, three univeriant curves related to the secondary crystallization, a ternary eutectic E (46.8% LaCl3, 25.4% SrCl, 30.0% LiCl; 469℃) in the system. A ternary reaction occurred in the system:L = LaCl3 + SrCl2 + LiCl

关键词： LaCl3-SrCl2-LiCl SYSTEM TERNARY OF PHASE DIAGRAM INVESTIGATION

Sol-Gel processing and novel physical properties of PLZT7/57/43 ferroelectric ceramics

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Sol-Gel processing and novel physical properties of PLZT7/57...