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Development of short prototype of dual aperture quadrupole magnet for CEPC ring

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Nuclear Science and Techniques 2023年第7期34卷 148-158页

作者： Mei Yang Fu-san Chen Ya-Feng Wu Zhuo zhang Bao-Gui Yin Bin Na zhan-Jun zhang Institute of High Energy Physics Chinese Academy of SciencesBeijing 10049China Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Beijing HE-Racing Technology Co. Ltd.Beijing 1000049China

Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)***,the field crosstalk between the two apertures presents *** the CEPC will work at four beam energies of Z,W,Higgs and ttbar mode,the DAQ magnets will operate at four field gradients spanning from 3.18 to 12.63 T/*** first short quadrupole magnet prototype with the bore diameter of 76 mm and magnetic length of 1.0 m revealed the problems of large magnetic field harmonics and a magnetic center shift within the beam energy ***,a compensation method was proposed in this work to solve the field crosstalk *** adjusting the gap height at the middle of the two apertures,the field harmonics and magnetic center shift are significantly *** optimization,the short prototype was modified using a new *** field simulations are validated from the magnetic measurement ***,the multipole field meets the requirements of the four beam *** detailed magnetic field optimization,field harmonics adjustment,and measurement results are presented herein.

关键词： Dual aperture magnets Field measurements Crosstalk effect Quadrupole magnet Field harmonics CEPC

Rice planting acceleration of the activation and loss of soil iron in the red soil region of southern China

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Soil Ecology Letters 2024年第2期6卷 179-187页

作者： san’an Nie Jie Fan Ningxiang Ouyang Hao Sheng Yangzhu zhang Xiong Yan zhan Yu College of Resources Hunan Agricultural UniversityChangsha410125China School of Economic Geography Hunan University of Finance and EconomicsChangsha410205China Zunyi Normal University Zunyi563006China

Rice planting decreased total iron but increased active *** activation varied greatly among different paddy soils but not in woodland *** soil iron was mainly affected by pH,SOC and particle *** decrease of soil Fe wa... 详细信息

关键词： paddy soil iron forms parent material rice planting Fe activation

Hamiltonian of Green–Schwarz IIB superstring Theory in AdS_(3)×S^(3) Background

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Chinese Physics Letters 2011年第7期28卷 73-76页

作者： KE san-Min WANG Chun WANG zhan-Yun JIANG Ke-Xia SHI Kang-Jie College of Science Chang'an UniversityXi'an 710064 Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064 College of Science Xi'an Shiyou UniversityXi'an 710065 Institute of Modern Physics Northwest UniversityXi'an 710069 School of Electronic Engineering Xi'an Institute of Posts and TelecommunicationsXi'an 710121 Department of Physics Engineering College of CAPFXi'an 710086

We parameterize the Green–Schwarz IIB superstring in the AdS_(3)×S^(3) background under the light cone gauge by the method of Metsaev and Tseytlin in AdS3 and by the method of Rahmfeld and Rajaraman in *** some calculation,we obtain the corresponding Maurer–Cartan 1−forms and the *** we fix two bosonic variables x+=τand y^(5)=σ,perform the partial Legendre transformation of the remaining bosonic variables,and find a Lagrangian that is linear in velocity after eliminating the metric of the world *** also give the Hamiltonian and prove that the system is local and the Poisson bracket of the theory can be well *** these results,one can further study the properties of solution space,solution transformation and the structure of the flat current algebra of the superstring in the AdS_(3)×S^(3) background.

关键词： Schwarz Cartan Legendre

Abnormal Shift of Center Wavelength in Annealing Long-Period Gratings

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Chinese Physics Letters 2000年第1期17卷 28-30页

作者： QIN Li WEI zhan-Xiong WANG Qing-Ya LI Hui-Ping zhanG Yu-Shu GAO Ding-san Department of Electronics Engineering Jilin UniversityChangchun 130023

During annealing process of long-period gratings,the center wavelengths of some inodes shift to red wavelength while those of others shift to blue compared with their original written ones,and the magnitudes of the shifts are related to the decay of the grating *** red shifts of center wavelength are more evident in lower-order inodes of the *** suggest that part of the photodissociated-H2 combines continuously with Ge-defect centers within 2 h after UV-exposure,and with which the observed abnormal shifts can be explained successfully.

关键词： center Shift annealing

A multi-objective optimization approach for harnessing rainwater in changing climate

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Advances in Climate Change Research 2024年第5期15卷 976-987页

作者： Ling-Yu MENG zhan TIAN Dong-Li FAN Frans H.M.VAN DE VEN Laixiang suN Qing-Hua YE san-Xiang suN Jun-Guo LIU Laura NOUGUES Daan ROOZE School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China Guangdong Provincial Key Laboratory of Soil and Groundwater Poution Control School of Environmental Science and EngineeringSouthern University of Scienceand TechnologyShenzhen 518055China Pengcheng Laboratory Shenzhen 518000China Deltares Delft 2629 HVNetherlands Water Management Faculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2628 CNNetherlands Department of Geographical Sciences University of MarylandMaryland 20742United States School of Environmental and Municipal Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

As the world grapples with the profound impacts of climate change,water scarcity has become a pressing ***,there is a shortage of in-depth research on the trade-offs between water resource dependence and the economic,ecological,and social needs of arid and semi-arid regions like Lanzhou,*** cultivation in Lanzhou relies heavily on the Yellow River,often overlooking the potential of natural *** we first calibrated a water balance model through artificial precipitation experiments in a Soil and Water Conservation Demonstration Park in *** then developed a multi-objective optimization model to balance the cost-benefit considerations of various plausible measures across economic,ecological,and social dimensions in the searching for solutions that are more adaptable to climate change and local devel-opment *** simulations show that the solutions we designed can effectively manage water-shortage days,significantly reduce Yellow River water extraction,and improve cost-effectiveness,meeting 66%-80%of water needs for flower cultivation in the studied *** findings highlight the potential of rainwater collection and utilization solutions to mitigate water scarcity in arid and semi-arid cities,thereby enriching water resource management.

关键词： Rainwater harvesting Rainwater resource utilization Climate change adaptation Multi-objective decision making Arid and semi-arid regions

Effects of Incretin-based Therapies on Weight-related Indicators among Patients with Type 2 Diabetes: A Network Meta-analysis

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Biomedical and Environmental Sciences 2020年第1期33卷 37-47页

作者： XU Lu YU Shu Qing GAO Le HUANG Yi WU Shan Shan YANG Jun suN Yi Xin YANG Zhi Rong CHAI san Bao zhanG Yuan JI Li Nong suN Feng zhan Si Yan Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Mathematics and Statistics University of Maryland Baltimore CountyBaltimore MD 21250MarylandUSA National Clinical Research Center of Digestive Diseases Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China The Primary Care Unit School of Clinical MedicineUniversity of CambridgeCambridge CB21TNUK Department of Endocrinology and Metabolism Peking University International HospitalBeijing 102206China Department of Clinical Epidemiology and Biostatistics McMaster UniversityHamilton L8S 4L8OntarioCanada Department of Endocrinology and Metabolism Peking University People’s HospitalBeijing 100044China

Objective To evaluate the effects of incretin-based therapies on body weight as the primary outcome,as well as on body mass index(BMI)and waist circumference(WC)as secondary *** Databases including Medline,Embase,the Cochrane Library,and ***(***)were searched for randomized controlled trials(RCTs).Standard pairwise meta-analysis and network meta-analysis(NMA)were both carried *** risk of bias(ROB)tool recommended by the Cochrane handbook was used to assess the quality of *** analysis,sensitivity analysis,meta-regression,and quality evaluation based on the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)were also *** A total of 292 trials were included in this *** with placebo,dipeptidyl-peptidase IV inhibitors(DPP-4 Is)increased weight slightly by 0.31 kg[95%confidence interval(CI):0.05,0.58]and had negligible effects on BMI and *** with placebo,glucagon-like peptide-1 receptor agonists(GLP-1 RAs)lowered weight,BMI,and WC by-1.34 kg(95%CI:-1.60,-1.09),-1.10 kg/m2(95%CI:-1.42,-0.78),and-1.28 cm(95%CI:-1.69,-0.86),*** GLP-1 RAs were more effective than DPP-4 Is in lowering the three ***,the effects of GLP-1 RAs on weight,BMI,and WC were favorable.

关键词： Body mass index Body weight Diabetes mellitus Dipeptidyl-peptidase IV inhibitors Glucagon-like peptide-1 receptor agonists Network meta-analysis Waist circumference

Drug-coated balloons for the treatment of ostial left anterior descending or ostial left circumflex artery lesions:a patientlevel propensity score-matched analysis

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Journal of Geriatric Cardiology 2023年第10期20卷 716-727,I0001-I0005页

作者： Liang PAN Wen-Jie LU zhan-Ying HAN san-Cong PAN Xi WANG Ying-Guang SHAN Meng PENG Xiao-Fei QIN Guo-Ju suN Pei-Sheng zhanG Jian-Zeng DONG Chun-Guang QIU Department of Cardiovascular Medicine the First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Department of Cardiology Jincheng People’s HospitalJinchengChina Department of Cardiology the Fifth Affiliated Hospital of Zhengzhou UniversityZhengzhouChina

BACKGROUND Controversy exists as to the optimal treatment approach for ostial left anterior descending(LAD)or ostial left circumflex artery(LCx)***-coated balloons(DCB)may overcome some of the limitations of drug-eluting stents(DES).Therefore,we investigated the security and feasibility of the DCB policy in patients with ostial LAD or ostial LCx lesions,and compared it with the conventional DES-only *** We retrospectively enrolled patients with de novo ostial lesions in the LAD or LCx who underwent interventional *** were categorized into two groups based on their treatment approach:the DCB group and the DES *** treatment strategies in the DCB group involved the use of either DCB-only or hybrid strategies,whereas the DES group utilized crossover or precise stenting ***-year target lesion revascularization was the primary endpoint,while the rates of major adverse cardiovascular events,cardiac death,target vessel myocardial infarction,and vessel thrombosis were the secondary *** propensity score matching,we assembled a cohort with comparable baseline *** ensure result analysis reliability,we conducted sensitivity analyses,including interaction,and stratified *** Among the 397 eligible patients,6.25%of patients who were planned to undergo DCB underwent DES.A total of 108 patients in each group had comparable propensity scores and were included in the ***-year target lesion revascularization occurred in 5 patients(4.90%)and 16 patients(16.33%)in the DCB group and the DES group,respectively(odds ratio=0.264,95%CI:0.093–0.752,P=0.008).Compared with the DES group,the DCB group demonstrated a lower major adverse cardiovascular events rate(7.84%vs.19.39%,P=0.017).However,differences with regard to cardiac death,non-periprocedural target vessel myocardial infarction,and definite or probable vessel thrombosis between the groups were *** The utilization of

关键词： lesions balloon treatment

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压气机失速与喘振动态模型与仿真

推进技术 2016年第5期37卷 960-965页

作者：苏三买孙占恒吕烨刘俊杰西北工业大学动力与能源学院陕西西安710072 中航出版传媒有限责任公司北京100012

建立失速与喘振动态数学模型是压气机主动稳定控制的基础。针对Moore-Greitzer不可压缩压气机模型无法描述失速时失速团沿压气机周向旋转特性的不足,以该模型为基础,在压气机周向环面位置进行模型空间离散化,采用空间傅里叶模态重构压... 详细信息

建立失速与喘振动态数学模型是压气机主动稳定控制的基础。针对Moore-Greitzer不可压缩压气机模型无法描述失速时失速团沿压气机周向旋转特性的不足,以该模型为基础,在压气机周向环面位置进行模型空间离散化,采用空间傅里叶模态重构压气机局部流量、压升、转子与静子的动静态损失,建立了以流量、压升及损失为状态变量的多维状态空间方程形式分布式压气机模型。理论分析及仿真表明,所建模型既可实现稳态、失速、喘振工况下的压气机外部特性计算,也可模拟失速与喘振状态下压气机内部沿周向的流量及压力变化,实现失速与喘振动态特性仿真。

关键词：压气机失速与喘振分布式模型动态仿真

基于李亚普诺夫稳定性理论的压气机失速主动控制方法

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推进技术 2017年第11期38卷 2488-2495页

作者：刘俊杰苏三买孙占恒刘超西北工业大学动力与能源学院陕西西安710072 中国航发湖南动力机械研究所湖南株洲412002

针对压气机主动稳定控制方法中模态控制需要大量传感器及高频执行装置的不足,以喷气装置作为失速控制的执行机构,基于李亚普诺夫稳定性理论,利用回溯法设计了采用周向同步喷气的压气机预失速和过失速阶段的失速控制算法。理论分析和仿... 详细信息

针对压气机主动稳定控制方法中模态控制需要大量传感器及高频执行装置的不足,以喷气装置作为失速控制的执行机构,基于李亚普诺夫稳定性理论,利用回溯法设计了采用周向同步喷气的压气机预失速和过失速阶段的失速控制算法。理论分析和仿真结果表明,采用该方法,在预失速阶段,经过约1.1s持续喷气后,扰动的各阶模态的幅值均趋于0,各阶模态的相位均趋于恒定;在过失速阶段,持续约0.1s的喷气控制后,扰动的各阶模态被完全抑制,其各阶幅值趋于0,各阶模态相位趋于恒定;实现了对预失速和过失速的有效控制。由于以平均流量作为反馈输入,该方法只需安装少量传感器,且喷气装置的作动频率不高于50Hz,远低于模态控制方法。此外,采用同步喷气,也降低了执行机构的复杂性。

关键词：压气机失速李亚普诺夫稳定性理论主动稳定控制