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内蒙古农牧交错区典型黑土坡耕地土壤侵蚀空间分布特征

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水土保持研究 2025年第1期32卷 13-20页

作者：邹惠杰刘刚舒成博孙波刘亚张琼郭珍中国科学院教育部水土保持与生态环境研究中心黄土高原土壤侵蚀与旱地农业国家重点实验室中国科学院水利部水土保持研究所中国科学院大学西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室四川华标测检测技术有限公司

[目的]定量了解内蒙古典型黑土区土壤侵蚀速率，探究该区域土壤侵蚀空间分布特征，阐明土壤侵蚀坡面和区域空间分布规律，以期为区域水土流失治理提供参考。[方法]采集内蒙古农牧交错区（海拉尔区、额尔古纳市和牙克石市）典型黑土坡耕... 详细信息

[目的]定量了解内蒙古典型黑土区土壤侵蚀速率，探究该区域土壤侵蚀空间分布特征，阐明土壤侵蚀坡面和区域空间分布规律，以期为区域水土流失治理提供参考。[方法]采集内蒙古农牧交错区（海拉尔区、额尔古纳市和牙克石市）典型黑土坡耕地的土壤样品，利用137Cs示踪技术计算各采样点土壤侵蚀速率，结合小波分析的方法研究土壤侵蚀在坡面的分布特征。[结果]（1） 3个坡面所有采样点137Cs含量均小于背景值（1 984.24 Bq/m2）,表现为所有坡面土壤流失。（2） 3个地区的采样坡面平均侵蚀速率表现为：海拉尔[6 533.37 t/（km2·a）]>额尔古纳[4 174.35 t/（km2·a）]>牙克石[2 765.87 t/（km2·a）]。相同坡面的3个纵向断面的平均侵蚀速率相近，同一断面侵蚀速率的变异程度较高。（3）土壤侵蚀速率沿坡长呈强弱交替的周期性变化，但周期长度并不固定。大部分纵向断面存在周期长度为80～160 m和160～200 m的大小两个周期。部分纵向断面只存在一个周期长度为100～120 m的周期。[结论]该地区土壤侵蚀在坡面尺度表现为全坡面侵蚀且在纵向呈现周期性特征，在区域尺度呈现从东到西逐渐增加趋势。

关键词：土壤侵蚀典型黑土农牧交错带小波分析

Wakefields studies for the SXFEL user facility

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Nuclear Science and Techniques 2017年第7期28卷 29-35页

作者： Ming-Hao Song Chao Feng da-Zhang Huang Hai-Xiao Deng bo liu Dong Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesZhangjiang CampusShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China

Besides the original seeded undulator line,in the soft X-ray free-electron laser(SXFEL) user facility in Shanghai,a second undulator line based on self-amplified spontaneous emission is proposed to achieve 2-nm laser pulse with extremely high *** this paper,the beam energy deviation induced by the undulator wakefields is numerically calculated,and 3D and 2D results agree well with each *** beam energy loss along the undulator degrades the expected FEL output performances,i.e.,the pulse energy,radiation power and spectrum,which can be compensated with a proper taper in the *** the planned time-resolved diagnostic,a novel experiment is proposed to measure the SXFEL longitudinal wakefields.

关键词：用户设备能量耦合自由电子激光自放大自发辐射波荡器软X射线激光脉冲数值计算

Total synthesis of proposed structures ofjiangrines C and D

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Science China Chemistry 2016年第9期59卷 1205-1210页

作者： Zhijiang Zhang bo liu Key Laboratory of Green Chemistry & Technology of Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China State Key Laboratory of Natural Medicines China Pharmaceutical University Nanjing 210009 China

On the basis of the proposed structures of jiangrines C and D, a synthetic strategy was initiated from D-glyceraldehyde acetonide,a readily available chiral material. Through a linear seven-step synthesis, the target molecules were accomplished. However, all characteristic data of the synthetic 3 and 4 were found to be different from those of natural jiangrines C and D. Accordingly, the molecular structures of jiangrines should be revised and a possible molecular skeleton for them was proposed.

关键词： pyrrole alkaloid jiangrine total synthesis

电刺激诱导miR-741-3p调控Radil促进施万细胞的迁移

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中国组织工程研究 2025年第19期29卷 4038-4043页

作者：刘庆高博杨霄姜宇王培承德医学院附属医院河北省承德市067000 承德医学院河北省承德市067000

背景:越来越多的动物实验和临床研究证实电刺激可以促进周围神经损伤修复,具体的机制尚未完全明确。目的:探讨电刺激诱导miR-741-3p调控Radil对施万细胞迁移的影响。方法:①12只雄性SD大鼠,随机分为电刺激组和对照组,电刺激组在坐骨神... 详细信息

背景:越来越多的动物实验和临床研究证实电刺激可以促进周围神经损伤修复,具体的机制尚未完全明确。目的:探讨电刺激诱导miR-741-3p调控Radil对施万细胞迁移的影响。方法:①12只雄性SD大鼠,随机分为电刺激组和对照组,电刺激组在坐骨神经挤压伤后连续电刺激7 d,对照组在坐骨神经挤压后不做任何处理。术后第7天取损伤处神经,利用荧光原位杂交技术检测两组miR-741-3p的表达差异。②通过miRDB、TargetScan和miRWalk数据库预测miR-741-3p靶基因。③将miR-741-3p模拟物及其对照、miR-741-3p抑制物及其对照、Radil siRNA及其对照、miR-741-3p抑制物+Radil siRNA及miR-741-3p抑制物+siRNA对照对施万细胞进行转染,采用RT-PCR检测转染效率,Transwell小室检测施万细胞的迁移能力。结果与结论:①电刺激组神经残端miR-741-3p荧光强度低于对照组;②数据库预测结果显示有69个基因可能是miR-741-3p靶基因,Radil是预测靶基因之一,主要参与细胞黏附和迁移;③与miR-741-3p抑制物对照组相比,miR-741-3p抑制物组施万细胞迁移数增多(P<0.05);与miR-741-3p模拟物对照组相比,miR-741-3p模拟物组施万细胞迁移数减少(P<0.05);与siRNA对照组相比,Radil siRNA组施万细胞迁移数减少(P<0.05);④与miR-741-3p抑制物对照组相比,miR-741-3p抑制物组Radil的表达水平升高;与miR-741-3p模拟物对照组相比,miR-741-3p模拟物组Radil的表达水平降低;⑤与miR-741-3p抑制物+siRNA对照组相比,miR-741-3p抑制物+Radil siRNA组施万细胞迁移数减少(P<0.05)。结果表明,电刺激通过下调miR-741-3p调控Radi的表达来促进施万细胞迁移。

关键词：施万细胞电刺激 miR-741-3p Radil 细胞迁移神经再生

Homographic Solutions of the N-body Generalized Lennard-Jones System

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Acta Mathematica Sinica,English Series 2020年第5期36卷 597-604页

作者： bo Wen liu School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.China Chern Institute of Mathematics Nankai UniversityTianjin 300071P.R.China

In this paper,we obtain the existence of non-planar circular homographic solutions and non-circular homographic solutions of the(2+N)-and(3+N)-body problems of the Lennard-Jones *** results show the essential differen... 详细信息

关键词： Homographic solution Lennard-Jones potential non-planar circular solution

Blind adaptive constrained constant modulus algorithms based on unscented Kalman filter for beamforming

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Journal of Central South University 2017年第10期24卷 2342-2352页

作者： QIAN Hua-ming liu Ke JIAO Zhi-bo MA Jun-da College of Automation Harbin Engineering UniversityHarbin 150001China Hainengda Communication Co. Ltd.Shenzhen 518000China

This work proposes constrained constant modulus unscented Kalman filter(CCM-UKF) algorithm and its low-complexity version called reduced-rank constrained constant modulus unscented Kalman filter(RR-CCM-UKF) algorithm for blind adaptive beamforming. In the generalized sidelobe canceller(GSC) structure, the proposed algorithms are devised according to the CCM criterion. Firstly, the cost function of the constrained optimization problem is transformed to suit the Kalman filter-style state space model. Then, the optimum weight vector of the beamformer can be estimated by using the recursive formulas of UKF. In addition, the a priori parameters of UKF(system and measurement noises) are processed adaptively in the implementation. Simulation results demonstrate that the proposed algorithms outperform the existing methods in terms of convergence speeds, output signal-tointerference-plus-noise ratios(SINRs), mean-square deviations(MSDs) and robustness against steering mismatch.

关键词： constrained constant modulus criterion blind beamforming unscented Kalman filter generalized sidelobe canceller

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采用阻流器的近壁面海底管道绕流研究

大连理工大学学报 2025年第1期65卷 89-96页

作者：王杰刘政沅张彬滨宋朝周波大连理工大学船舶工程学院辽宁大连116024

为深入了解采用阻流器的海底管道自埋机制,基于Fluent软件,结合标准k-ε湍流模型,建立了高雷诺数下安装阻流器的近壁面海底管道绕流数值模型,研究了阻流器长度和间隙比对管道尾流与壁面边界层之间复杂的相互作用以及时空演化的影响.研... 详细信息

为深入了解采用阻流器的海底管道自埋机制,基于Fluent软件,结合标准k-ε湍流模型,建立了高雷诺数下安装阻流器的近壁面海底管道绕流数值模型,研究了阻流器长度和间隙比对管道尾流与壁面边界层之间复杂的相互作用以及时空演化的影响.研究结果表明采用阻流器可以显著增大管道与壁面之间流速以及管道附近脉动速度,但当阻流器长度达到临界值时,管道尾部会形成稳态结构.随着间隙比的增大,尾流演化可以分为4个区域:稳态结构、两次诱导壁面涡、单次诱导壁面涡、卡门涡街.适当的间隙比有利于诱导壁面旋涡的产生,从而加快管道周围沉积物冲刷.

关键词：阻流器海底管道壁面圆柱绕流湍流

Numerical Investigation and Non-Axisymmetric Endwall Profiling of a Turbine Stage

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Journal of Thermal Science 2019年第4期28卷 811-825页

作者： REHMAN Abdul liu bo School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China Shaanxi Key Laboratory of Internal Aerodynamics in Aero-Engine Xi’an 710072China

This paper presents an optimization of a high pressure turbine by constructing non-axisymmetric endwalls to the stator row and the rotor *** optimization was quantified by using optimization algorithms based on the multi-objective *** objective was to increase total-to-total efficiency with the constraint on the mass flow rate equal to the design point *** order to ensure that global optimum could be achieved,the function of parameters was first approximated through the artificial neural network,and then optimum was achieved by implementing the genetic *** was adopted through the design and optimization environment of FineTM/Design3 *** individual treatments of the endwalls were ***,the hub and the shroud of the stator were optimized ***,the hub of the rotor was ***,the rotor hub was optimized in the presence of the optimized *** result of the investigation showed that the optimized shape of the endwalls can significantly help to increase the efficiency up to 0.18%with the help of a reduction of the transverse pressure *** coefficient of secondary kinetic energy,entropy coefficient,spanwise mass averaged entropy were *** order to investigate the periodic effects,the design of the optimized turbine under steady simulations was confirmed through unsteady *** last part of the investigation made sure that the performance improvement remained consistent over the full operating line at off-design conditions by the implementation of non-axisymmetric endwalls.

关键词： optimization non-axisymmetric endwall high pressure turbine stage efficiency secondary kinetic energy steady unsteady off-design

Effect of seepage-induced erosion on soil macropore structure

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Journal of Mountain Science 2023年第11期20卷 3402-3422页

作者： HUANG Wen-bo HUANG da GAO Yi-kang liu Yang LI Zhao MENG Qiu-jie School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China. College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China.

Internal erosion is one of the important factors causing geological *** microstructure of soil can change with seepage erosion,resulting in changes in the hydraulic and mechanical properties of the *** evolution of seepage erosion is investigated with X-ray computed tomography(CT)in this *** change in macropore structure characteristics during the seepage erosion test is quantified and the influence of seepage erosion on soil deformation is ***,a pore network model(PNM)is established for the specimens and the evolution of the connected pore size characteristics is *** results show that the macropore structure is significantly affected by seepage erosion,especially in terms of the porosity and pore geometry *** changes in macropore structure characteristics are most obvious in the lower part of the *** influence of seepage erosion on the pore size distribution(PSD)and soil deformation is heterogeneous and closely dependent on the spatial location of the ***,seepage erosion enhances macropore connectivity and has a directional impact on macropore *** findings can provide a reference for the theoretical modeling and numerical simulation of the seepage erosion and improve the understanding of the seepage erosion evolution in engineering practice.

关键词： Seepage erosion Heterogeneity Macropore structure Pore size distribution Microstructure CT scanning