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Mongolia Contributed More than 42%of the Dust Concentrations in Northern China in March and April 2023

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Advances in Atmospheric Sciences 2023年第9期40卷 1549-1557页

作者： Siyu CHEN Dan ZHAO Jianping HUANG Jiaqi HE Yu CHEN Junyan CHEN hongru bi Gaotong LOU Shikang DU Yue ZHANG Fan YANG Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou UniversityLanzhou 730000China Institute of Desert Meteorology China Meteorological AdministrationUrumqi 830002China

Dust storms are one of the most frequent meteorological disasters in China,endangering agricultural production,transportation,air quality,and the safety of people’s lives and *** the backdrop of climate change,Mongolia’s contribution to China’s dust cannot be ignored in recent *** this study,we used the Weather Research and Forecasting model coupled with Chemistry(WRF-Chem),along with dynamic dust sources and the HYSPLIT model,to analyze the contributions of different dust sources to dust concentrations in northern China in March and April *** results show that the frequency of dust storms in 2023 was the highest observed in the past *** and the Taklimakan Desert were identified as two main dust sources contributing to northern ***,Mongolia contributed more than 42%of dust,while the Taklimakan Desert accounted for 26%.A cold high-pressure center,a cold front,and a Mongolian cyclone resulted in the transport of dust aerosols from Mongolia and the Taklimakan Desert to northern China,where they affected most parts of the ***,two machine learning methods[the XGBoost algorithm and the Synthetic Minority Oversampling Technique(SMOTE)]were used to forecast the dust storms in March 2023,based on ground observations and WRF-Chem simulations over East ***-SMOTE performed well in predicting hourly PM10 concentrations in China in March 2023,with a mean absolute error of 33.8μg m−3 and RMSE of 54.2μg m−3.

关键词： dust aerosol Mongolian dust transboundary contribution WRF-Chem HYSPLIT model

干旱半干旱区农田土壤风蚀特征及参数化研究进展

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中国沙漠 2022年第3期42卷 105-117页

作者：张越陈思宇毕鸿儒曹佳慧罗源龚咏琪陈渔兰州大学大气科学学院/半干旱气候变化教育部重点实验室甘肃兰州730000 湖南省气象台/湖南省气象局湖南长沙410118

干旱半干旱地区是中国的农业后备战略基地,然而近年来该地区农田土壤风蚀现象严重,沙/尘释放量显著增大,威胁农业的可持续发展和生态系统平衡。目前绝大部分的天气和气候模式仅考虑了沙漠地表起沙,忽视退化农田的土壤风蚀起沙,导致起沙... 详细信息

干旱半干旱地区是中国的农业后备战略基地,然而近年来该地区农田土壤风蚀现象严重,沙/尘释放量显著增大,威胁农业的可持续发展和生态系统平衡。目前绝大部分的天气和气候模式仅考虑了沙漠地表起沙,忽视退化农田的土壤风蚀起沙,导致起沙通量模拟存在很大的不确定性。对20世纪50年代以来干旱半干旱区农田土壤风蚀起沙特征及参数化做了详细的分析总结,回顾并梳理了干旱半干旱区农田土壤风蚀观测和数值模拟的研究脉络以及存在的问题,为提高农田起沙的模拟精度提供了有效参考,对中国干旱半干旱区农田土壤风蚀防治、土地荒漠化治理以及理解未来土地利用改变对大气污染的影响具有重要意义。

关键词：干旱半干旱区农田土壤风蚀风洞试验起沙参数化

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沙尘天气识别和预报方法研究综述

中国沙漠 2024年第1期44卷 11-21页

作者：陈思宇杜世康毕鸿儒赵丹张越陈渔娄高僮陈俊言兰州大学大气科学学院甘肃兰州730000 兰州大学半干旱气候变化教育部重点实验室甘肃兰州730000 兰州大学资源环境学院甘肃兰州730000

沙尘天气是极端天气现象,会使空气浑浊、能见度骤降,给人类社会各个方面带来恶劣影响;沙尘气溶胶还通过改变大气辐射收支及云微物理特性对天气气候产生重要影响。围绕沙尘天气的相关研究一直是灾害天气预报领域中重要的研究方向,准确识... 详细信息

沙尘天气是极端天气现象,会使空气浑浊、能见度骤降,给人类社会各个方面带来恶劣影响;沙尘气溶胶还通过改变大气辐射收支及云微物理特性对天气气候产生重要影响。围绕沙尘天气的相关研究一直是灾害天气预报领域中重要的研究方向,准确识别和预报沙尘天气在生态环境保护、气候变化等方面均具重要意义。回顾了近年来关于沙尘天气识别与预报方法相关的研究成果,对重要的方法进行了详细介绍,同时分析比较了不同方法的优缺点。最后,对沙尘天气识别与预报相关的研究成果进行了总结,并展望了有价值的研究方向。

关键词：沙尘天气沙尘天气识别沙尘天气预报数值模拟机器学习

戈壁沙漠沙尘向青藏高原传输路径和传输机制:以2020年4月一次沙尘事件为例

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中国沙漠 2024年第3期44卷 158-171页

作者：陈俊言贯雅雯张越陈渔毕鸿儒娄高僮郭馨阳王洋陈思宇兰州大学大气科学学院/半干旱气候变化教育部重点实验室甘肃兰州730000

戈壁沙漠是沙尘天气频发区域,也是东亚沙尘暴的关键源地。青藏高原毗邻东亚和南亚两大沙源区,是全球气候变化的敏感地区。然而戈壁沙漠沙尘向青藏高原传输路径以及传输机制尚不清晰。基于区域空气质量模式WRF-Chem、FNL再分析资料并结合... 详细信息

戈壁沙漠是沙尘天气频发区域,也是东亚沙尘暴的关键源地。青藏高原毗邻东亚和南亚两大沙源区,是全球气候变化的敏感地区。然而戈壁沙漠沙尘向青藏高原传输路径以及传输机制尚不清晰。基于区域空气质量模式WRF-Chem、FNL再分析资料并结合HYSPLIT后向轨迹模型,以2020年4月戈壁沙漠一次强沙尘事件为例,探讨了戈壁沙漠沙尘向青藏高原传输路径以及传输机制。结果表明:在此次沙尘事件期间,青藏高原东坡和北坡是戈壁沙漠沙尘传输至青藏高原的重要通道。受环流形势和高大地形的影响,青藏高原北坡沙尘传输效率大于东坡,而东坡沙尘垂直运动较北坡旺盛。500 hPa乌拉尔山以东的气旋系统和蒙古气旋共同控制中高纬度带,影响沙尘输送过程。随着中高纬气旋系统的东移,500 hPa新疆脊被破坏,青藏高原上空短波槽开始建立。短波槽前低层辐合的环流场有利于700 hPa闭合低压的维持,促使青藏高原北坡的偏北大风产生,有利于北坡沙尘向青藏高原输送。200 hPa高空急流动量下传引起河西走廊近地东风盛行,有利于戈壁沙漠沙尘从东坡向青藏高原输送。此环流形势构成了戈壁沙漠沙尘向青藏高原传输的有利风场。该研究成果进一步完善了戈壁沙漠沙尘的传输路径,为研究沙尘影响青藏高原及其周边地区的天气气候变化提供了科学支撑。

关键词：沙尘气溶胶远距离输送戈壁沙漠青藏高原 WRF-Chem HYSPLIT

Structure and Magnetic Properties of Sputtered bi_(2)DyFe_(5)O_(12) Films

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Chinese Physics Letters 1994年第1期11卷 61-64页

作者： GU Benxi ZHANG Hongyan ZHAI hongru LU Mu MIAO Yongzhi Department of Physics Nanjing UniversityNanjing 210008

The effects of the annealing temperature and time on the structure and magnetic properties of the sputtered biDy-iron garnet films were investigated.X-ray diffraction analysis shows that the as-sputtered films are *** annealing at about 550℃,amorphous films crystallize into the garnet phase and an unknown *** intensity of the unknown phase decreases with increasing annealing temperature and time and vanishes at 650℃for *** is found that the unknown phase has a large influence on the half-width of the(420)x-ray diffraction *** as-sputtered films have a very small magnetization of about 1 emu/g at room *** films are annealed above 570℃,the magnetization increases rapidly with increasing annealing temperature and time.

关键词： temperature. annealing amorphous

混凝土爆破损伤的SPH-FEM耦合法数值模拟

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爆炸与冲击 2018年第6期38卷 1419-1428页

作者：王志亮毕程程李鸿儒合肥工业大学土木与水利工程学院安徽合肥230009

为了提高计算效率以及更好展现爆炸荷载下混凝土破坏过程,采用SPH-FEM耦合法对混凝土爆破成坑进行模拟。首先结合前人给出的C30混凝土Holmquist-Johnson-Cook(HJC)部分本构参数,通过理论推导等方法确定出剩余的参数;然后代入模型中计算... 详细信息

为了提高计算效率以及更好展现爆炸荷载下混凝土破坏过程,采用SPH-FEM耦合法对混凝土爆破成坑进行模拟。首先结合前人给出的C30混凝土Holmquist-Johnson-Cook(HJC)部分本构参数,通过理论推导等方法确定出剩余的参数;然后代入模型中计算,将数值解与实测数据进行对比;最后以峰值压力和峰值加速度作为考察对象,对HJC模型中21个参数敏感性进行分析。结果表明:SPH-FEM耦合法能直观地模拟爆炸荷载作用下爆坑的发展全过程,且能够较好地处理SPH边界问题;基于所给出的C30混凝土HJC本构参数,采用SPH-FEM耦合法对混凝土爆破破坏进行模拟,计算结果与实测数据吻合度高,表明HJC本构参数的确定具有合理性。此外,还发现HJC本构参数对爆破问题结果的敏感度各不相同,指出对峰值压力和峰值加速度均有较大影响的参数在确定的时候需引起足够的重视。

关键词：混凝土爆破损伤 SPH-FEM耦合法 HJC本构参数敏感度

Efficient Rescue for Resilient Multi-Robot Systems against Actuation Attacks

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Efficient Rescue for Resilient Multi-Robot Systems against A...

LIN28 coordinately promotes nucleolar/ribosomal functions and represses the 2C-like transcriptional program in pluripotent stem cells

第43届中国控制会议

作者： hongru Li Xin Gong School of Cyber Science and Engineering Southeast University

The widespread application of intelligent storage systems has put forward higher requirements for security. In this work, we consider the resilience of multi-robot systems(MRSs) in pickup and delivery tasks against actuation attacks. The attacker can disrupt the normal motion of key robots with an intelligent strategy, and thus jeopardize the cooperation among robots. A three-layered decision framework is proposed to suppress the intelligent attacks. The first layer introduces a defense strategy implemented through a counterfactual rescue mode allocation mechanism. The mechanism dynamically assesses the benefit differences between rescuing others for resilience and conducting self-tasks for efficiency. The second layer employs a bi-level programming method for pickup/delivery mode allocations and task assignments. Then, the third layer calculates the robots' collision-free path using a mixed integer program. The practicality and resilience of this framework against strategic actuation attacks have been demonstrated through numerical simulations involving various MRS scales and task burdens.

关键词： Efficient Rescue Task Assignment Multi-Robot Systems Pickup and Delivery Actuation Attacks

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Protein & Cell 2022年第7期13卷 490-512页

作者： Zhen Sun Hua Yu Jing Zhao Tianyu Tan hongru Pan Yuqing Zhu Lang Chen Cheng Zhang Li Zhang Anhua Lei Yuyan Xu Xianju bi Xin Huang Bo Gao Longfei Wang Cristina Correia Ming Chen Qiming Sun Yu Feng Li Shen Hao Wu Jianlong Wang Xiaohua Shen George Q.Daley Hu Li Jin Zhang Center for Stem Cell and Regenerative Medicine Department of Basic Medical Sciences and the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310058China Department of Molecular Pharmacology&Experimental Therapeutics Center for Individualized MedicineMayo ClinicRochesterMNUSA Tsinghua-Peking Center for Life Sciences School of MedicineTsinghua UniversityBeijing 100085China The Black Family Stem Cell Institute and Department of Cell Developmental and Regenerative BiologyIcahn School of Medicine at Mount SinaiNew YorkNY 10029USA Department of biophysics and Department of Pathology of Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou 31005&China Department of biological Chemistry and Molecular Pharmacology Harvard Medical Schooland Program in Cellular and Molecular MedicineBoston Children's HospitalBostonMAUSA Stem Cell Transpla ntation Program Division of Pediatric Hematology On cologyBost on Children's HospitalDepartme nt of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonMAUSA College of Life Sciences Zhejiang UniversityHangzhou 310058China Department of biochemistry Zhejiang University School of MedicineHangzhou 310058China Institute of Life Science Zhejiang UniversityHangzhou 310058China Institute of Hematology Zhejiang UniversityHangzhou 310058China Zhejiang Laboratory for Systems and Precision Medicine Zhejiang University Medical CenterHangzhou 310058China

LIN28 is an RNA binding protein with important roles in early embryo development,stem cell differentiation/re-programming,tumorigenesis and *** studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs,and few have addressed LIN28's role within the ***,we show that LIN28 displays dynamic temporal and spatial expression during murine embryo *** LIN28 expression drops upon exit from the 2-cell stage,and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blas-tocyst stage development,to become dominantly expressed in the cytosol after *** cultured pluripotent stem cells(PSCs),loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus ***,LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity,and its loss leads to nucleolar phase separation defects,ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor ***28 also resides in a complex containing the nucleolar factor Nucleolin(NCL)and the transcrip-tional repressor TRIM28,and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci,and thus de-repressed Dux and reduced rRNA ***28 knockout cells with nucleolar stress are more likely to assume a slowly cycling,translationally inert and anabolically inactive state,which is a part of previously unappreciated 2C-like transcriptional *** findings elucidate novel roles for nucleolar LIN28 in PSCs,and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.

关键词： LIN28 2-cell-like program nucleolar integrity NCL/TRIM28 complex

Comprehensive test stand for high-intensity cyclotron development

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Chinese Science Bulletin 2011年第3期56卷 238-244页

作者： ZHANG TianJue LI ZhenGuo CHU ChengJie XING JianSheng GUAN FengPing ZHONG JunQing JI bin GE Tao YIN ZhiGuo HOU ShiGang PAN GaoFeng YAO HongJuan LU YinLong WANG ZhenHui WU LongCheng LIN Jun JIA XianLu WEI SuMin WEN LiPeng WANG Feng XIA Le CAI hongru XIE HuaiDong CHEN RongFan ZHANG Yan ZHANG SuPing LIU GengShou ZOU Jian AN ShiZhong YANG JianJun bi YuanJie YANG Fang China Institute of Atomic Energy Beijing 102413 China

A comprehensive test stand for high-intensity cyclotron development,a 10 MeV 430 μA cyclotron,has been successfully constructed at China Institute of Atomic Energy (CIAE) for the experimental verification of the viability of a 100 MeV high-intensity cyclotron (CYCIAE-100) being constructed at *** verification includes the overall design technology,detail design and engineering technology for the crucial parts of the machine,*** magnet and beam *** will also pave the way for future enhancement of the beam *** test stand consists of a H-ion source,axial injection system,central region,main magnet and coil,RF resonator,stripping extraction,and auxiliary systems,which include the RF power amplifier,high voltage and DC power supplies,electric apparatus,beam diagnostics,control,vacuum,water cooling,pneumatic system,and safety *** paper presents the work regarding the design and sub-system development of the test sand,and the results of the beam commissioning of the machine.

关键词：回旋加速器高强度试验台原子能科学研究院射频功率放大器中国科学院轴向注入系统工程技术