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Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-Liang Pu Yan-Lin Ye jian-Ling lou Jia-Hao Chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control *** proposed digital system can be combined with a conventional analog data acquisition system to provide more *** performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

含孔洞炸药晶体HMX冲击响应的分子动力学模拟

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含能材料 2024年第1期32卷 65-75页

作者：周婷婷楼建锋北京应用物理与计算数学研究所北京100094

动载荷下炸药晶体缺陷与热点形成的关联是当前含能材料领域的研究热点之一,理解热点形成机制及其对炸药起爆和感度的影响对于炸药安全性评估和研制安全弹药至关重要。本研究采用ReaxFF反应力场和分子动力学方法,对含圆柱形孔洞的炸药单... 详细信息

动载荷下炸药晶体缺陷与热点形成的关联是当前含能材料领域的研究热点之一,理解热点形成机制及其对炸药起爆和感度的影响对于炸药安全性评估和研制安全弹药至关重要。本研究采用ReaxFF反应力场和分子动力学方法,对含圆柱形孔洞的炸药单晶奥克托金(HMX)在冲击载荷下的动态响应进行了研究,并探究了孔洞尺寸和双孔洞的影响。结果表明,冲击载荷下孔洞的塌缩过程分为3个阶段,即孔洞上游的塑性变形、上游原子向孔洞中心和下游运动形成流动原子、流动原子与下游碰撞。热点形成的主要机制是流动原子与下游碰撞使得动能转换为热能导致温度快速升高。热点的高温诱发了局部化学反应,HMX分子中N─NO2键断裂生成NO2是主要的初始反应机制。圆柱形孔洞的塌缩过程和热点形成机制与球形孔洞是相似的,但圆柱形孔洞的汇聚效应更弱、形成的流动原子速度更低,导致热点温度显著降低、化学反应更弱。此外,圆柱形孔洞在塌缩过程中在其周围形成了剪切带,这在球形孔洞中没有出现。随着孔洞尺寸的增大,流动原子的速度提高、剪切带变宽、热点温度升高且面积增大,进而引发了更剧烈的化学反应。对于沿冲击方向排布相距一个孔洞半径的双孔洞,孔洞塌缩过程与单孔洞是类似的,但由于冲击波在传过上游孔洞后压力有所降低,导致下游孔洞在塌缩过程中形成的流动原子速度更小、热点温度更低。本研究有助于深入理解晶体缺陷对炸药热点形成与起爆机理的作用,为宏观理论建模提供物理机制与规律认识。

关键词：炸药孔洞热点化学反应分子动力学

Directional Solidification Assisted by Liquid Metal Cooling

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Journal of Materials Science & Technology 2007年第3期23卷 289-300页

作者： jian ZHANG Langhong lou Superalloys Division Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

An overview of the development and current status of the directional solidification process assisted by liquid metal cooling （LMC） has been presented in this paper. The driving force of the rapid development of the LMC process has been analyzed by considering the demands of （1） newer technologies that can provide higher thermal gradients for alleviated segregation in advanced alloy systems, and （2） better production yield of the large directionally solidified superalloy components. The brief history of the industrialization of the LMC process has been reviewed, followed by the discussion on the LMC parameters including selection of the cooling media, using of the dynamic baffle, and the influence of withdrawal rates and so on. The microstructure and mechanical properties of the traditional superalloys processed by LMC, as well as the new alloys particularly developed for LMC process were then described. Finally, future aspects concerning the LMC process have been summarized.

关键词： Directional solidification Liquid metal cooling Superalloys Microstructure Mechanical properties

Distributed incremental bias-compensated RLS estimation over multi-agent networks

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Science China(Information Sciences) 2017年第3期60卷 153-167页

作者： jian lou Lijuan JIA Ran TAO Yue WANG School of Information and Electronics Beijing Institute of Technology

In this paper, we study the problem of distributed bias-compensated recursive least-squares(BCRLS) estimation over multi-agent networks, where the agents collaborate to estimate a common parameter of interest. We consider the situation where both input and output of each agent are corrupted by unknown additive noise. Under this condition, traditional recursive least-squares(RLS) estimator is biased, and the bias is induced by the input noise variance. When the input noise variance is available, the effect of the noise-induced bias can be removed at the expense of an increase in estimation variance. Fortunately, it has been illustrated that distributed collaboration between agents can effectively reduce the variance and can improve the stability of the estimator. Therefore, a distributed incremental BC-RLS algorithm and its simplified version are proposed in this paper. The proposed algorithms can collaboratively obtain the estimates of the unknown input noise variance and remove the effect of the noise-induced bias. Then consistent estimation of the unknown parameter can be achieved in an incremental fashion. Simulation results show that the incremental BC-RLS solutions outperform existing solutions in some enlightening ways.

关键词： distributed parameter estimation bias compensation incremental schemes recursive least-squares multi-agent networks

Decompositions of the Hardy space _z^1(Ω)

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Acta Mathematica Sinica,English Series 2005年第4期21卷 949-954页

作者： Zeng jian lou Shou Zhi YANG Dao Jin SONG Department of Mathematics Shantou University Shantou 515063 P. R. China Teaching Division of Computer Science Shandong University of Technology Zibo 255091 P. R. China

We give a decomposition of the Hardy space Hz^1（Ω） into ＂div-curl＂ quantities for Lipschitz domains in R^n. We also prove a decomposition of Hz^1（Ω） into Jacobians det Du, u ∈ W0^1,2 （Ω,R^2） for Ω in R^2.... 详细信息

关键词： Hardy space Lipschitz domain, Jacobian determinant

Effects of Haobie Yangyin Ruanjian Decoction on hepatic fibrosis induced by carbon tetrachloride in rats

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World Journal of Gastroenterology 2010年第12期16卷 1458-1464页

作者： Yang, Feng-Rui Fang, Bu-Wu lou, jian-Shi Tianjin Med Univ Dept Pharmacol Tianjin 300070 Peoples R China

AIM:To explore the anti-fibrotic effect of Haobie Yangyin Ruanjian Decoction(HYRD)on CCl4-induced hepatic fibrosis in rats and its modulation on the transforming growth factor(TGF)β-Smad signaling ***:Fifty-six healthy Wistar rats were randomly divided into five groups:normal control group(n=6),CCl4-induced hepatic fibrosis group(n=14) and three treatment groups(the treated rats received HYRD via oral administration at daily dosages of 8.2,2.5 and 0.82 g/kg,respectively)of HYRD(n=12,respectively).Experimental hepatic fibrosis was induced by subcutaneous injection of carbon tetrachloride solution(CCl4 dissolved in peanut oil,4:6,V/V)with 0.5 mL/100 g body weight for the first time,and then 0.3 mL/100 g body weight twice a week for 8 *** the former 2 wk,rats were raised by feedstuffⅠ(80% corn meal,20%lard,0.5%cholesterol).After 2 wk,they were raised by feedstuffⅡ(corn meal and 0.5% cholesterol).Except for the control group,30%alcohol solution was given orally to each rat every other day from the beginning,1 mL for each *** function parameters and hepatic hydroxyproline content were detected by *** levels of hyaluronic acid(HA),typeⅣcollagen(CIV),typeⅢprecollagen(PCⅢ)and laminin(LN)were assayed with *** of collagen was observed with hematoxylin-eosin staining and collagen *** expression of TGFβ1 and Smad3 were detected with real-time reverse transcriptase-polymerase chain reaction and Western blotting,***:The serum levels of alanine transaminase and aspartate transaminase were increased in the model group compared with the control group(P<0.01),and they were decreased in the three treatment groups compared with the model *** serum levels of total protein and albumin were decreased in the model group and increased in the three treatment *** hepatic hydroxyproline content and serum levels of PCⅢ,HA,LN and CIV were markedly increased in the model group compared with the con

关键词： Haobie Yangyin Ruanjian Decoction Hepatic fibrosis Transforming growth factorβ-Smad signaling Rat model Carbon tetrachloride

基于专用测量仪的新型城市轨道交通站台门测量安装及精度控制技术

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价值工程 2024年第1期43卷 140-143页

作者：李建楼朱伟李博潘磊中船海为高科技有限公司郑州450052

本文介绍了一种新型的城市轨道交通站台门测量安装及精度控制技术,该技术以专用测量仪器为基础,提供了一种高效、精准的安装方法。这项技术主要包括两个核心环节:高精度的测量和自动化控制的安装调整。技术利用高精度激光测距仪进行关... 详细信息

本文介绍了一种新型的城市轨道交通站台门测量安装及精度控制技术,该技术以专用测量仪器为基础,提供了一种高效、精准的安装方法。这项技术主要包括两个核心环节:高精度的测量和自动化控制的安装调整。技术利用高精度激光测距仪进行关键点的测量,如轨道中心线、有效站台中心线和轨道控制基标点。这种方法相较于传统的水平仪、线锤、钢尺等工具,大大减少了测量误差,提高了测量的准确性和效率。该技术采用自动化控制系统来处理和调整测量数据,确保了安装过程中的精准控制和调整,从而提高了站台门系统的安装精度和质量。这一过程不仅提高了安装的准确性,也缩短了施工周期,并降低了施工成本。通过实施这一技术,城市轨道交通站台门系统的稳定性和可靠性得到了提升,同时也增强了整个城市轨道交通系统的运行效率和安全性。这项技术的高实用性和推广价值,为城市轨道交通的发展提供了有力的技术支持和保障,是城市轨道交通建设发展中的一项重要技术革新。

关键词：城市轨道交通站台门测量定位精度控制可靠性安全性

Effects of Fufang Biejia Ruangan Pills on hepatic fibrosis in vivo and in vitro

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World Journal of Gastroenterology 2013年第32期19卷 5326-5333页

作者： Feng-Rui Yang Bu-Wu Fang jian-Shi lou Department of Pharmacology Tianjin Medical University

AIM:To explore the protective effect and the relevant mechanisms of Fufang Biejia Ruangan Pills(FFBJRGP)on hepatic fibrosis in vivo and in ***:Hepatic fibrosis was induced by carbon tetrachloride composite *** Wistar rats were randomly divided into four groups:normal control group;hepatic fibrosis model group;FFBJRGP-treated group at a daily dose of 0.55 g/kg;and colchicinetreated group at a daily dose of 0.1 g/*** effects of FFBJRGP on liver function,serum levels of hyaluronic acid(HA),typeⅣcollagen(CⅣ),typeⅢprocollagen(PCⅢ),laminin(LN),histopathology,and expression of transforming growth factor(TGF-β1)and Smad3 in hepatic fibrosis were evaluated in *** effects of FFBJRGP on survival rate,hydroxyproline content and cell cycle distribution were further detected in ***:Compared with the hepatic fibrosis model group,rats treated with FFBJRGP showed a reduction in hepatic collagen deposition and improvement in hepatic *** with those of the model group,the activities of alanine aminotransferase(62.0±23.7 U/L)and aspartate aminotransferase(98.8±40.0 U/L)in the FFBJRGP-treated group were decreased(50.02±3.7 U/L and 57.2±30.0 U/L,respectively,P<0.01).Compared with those in the model group,the levels of PCⅢ(35.73±17.90 g/mL),HA(563.82±335.54 ng/mL),LN(89.57±7.59 ng/mL)and CⅣ(29.20±6.17ng/mL)were decreased to 30.18±9.41,456.18±410.83,85.46±7.51 and 28.02±9.45 ng/mL,***-transcriptase polymerase chain reaction and Western blotting also revealed that expression of TGF-β1 and Smad3 were down-regulated in *** proliferation was inhibited,the level of hydroxyproline was decreased compared with the control group(P<0.01),and the cell cycle was redistributed when exposed to FFBJRGP in ***:FFBJRGP inhibits hepatic fibrosis in vivo and in vitro,which is probably associated with downregulation of fibrogenic signal transduction of the TGF-β-Smad pathway.

关键词： Fufang Biejia Ruangan Pill Hepatic fibrosis Transforming growth factor-Smad signaling

Systematic CDCC calculations for ~11Be+p elastic scattering

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Science China(Physics,Mechanics & Astronomy) 2016年第3期59卷 70-74页

作者： Jie Chen jian Ling lou Dan Yang Pang Yan Lin Ye School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University School of Physics and Nuclear Energy Engineering Beihang University

Continuum discretised coupled-channels （CDCC） method with a 10Be（0＋）＋ n two-body cluster model is applied to systematically analyze the elastic scattering of the halo nucleus alBe from the proton target at various incident energies below 100 MeV/nucleon. Using the renormalized 10Be-p potential deduced from the 10Be ＋ p elastic scattering data, the differential cross sections of 11 Be ＋ p scattering are well reproduced by the CDCC calculations without any further adjustment parameters, demonstrating the applicability of this approach for describing the scattering of exotic nuclei based on the scattering of the less exotic core nuclei.

关键词： elastic scattering CDCC 11Be