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Highly coupled off-resonance lattice design in diffraction-limited light sources

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Nuclear Science and Techniques 2024年第9期35卷 92-102页

作者： Yi-Hao Gong Shun-Qiang Tian xin-zhong Liu Shou-Zhi Xuan Li-Yuan Tan Ling-Long Mao Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201204 ShanghaiChina Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 ShanghaiChina University of Chinese Academy of Sciences 100049 BeijingChina

The round-beam operation presents many benefits for scientific experiments regarding synchrotron radiation and the weak-ening influences of intra-beam scattering in diffraction-limited synchrotron light sources.A round-beam generation method based on the global setting of skew quadrupoles and the application of a non-dominated sorting genetic algorithm was pro-posed in this *** schemes,including large-emittance coupling introduced via betatron coupling and vertical disper-sion,were explored in a candidate lattice for an upgrade-proposal of the Shanghai synchrotron radiation *** variations with lattice imperfections and their influence on the beam dynamics of beam optic distortions were *** results demonstrated that a precise coupling control ranging from 10 to 100%was achieved under low optical distortion,whereas full-coupling generation and its robustness were achieved by our proposed method by adjusting the skew quadrupole components located in the dispersion-free *** Touschek lifetime increased by a factor of 2–2.5.

关键词： Diffraction-limited storage ring(DLSR) Shanghai synchrotron radiation facility upgrade(SSRF-U) Round beam Off-resonance coupling

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双字节离散数字混沌序列发生器芯片核

压电与声光 2007年第1期29卷 100-102页

作者：陈帅钟先信刘积学石军锋廖晓纬重庆大学光电技术及系统教育部重点实验室重庆400030 四川压电与声光技术研究所重庆400060 淮南师范学院物理系安徽淮南232001

为提高无线传感器网络节点的集成度,提出了用于传感器网络安全的双字节数字混沌序列发生器芯片核。采用混沌的数字计算法计算了双字节不同初始值的周期。由周期对应的不同分组初始值,产生3个离散数字混沌序列并进行同步二进制乘法运算,... 详细信息

为提高无线传感器网络节点的集成度,提出了用于传感器网络安全的双字节数字混沌序列发生器芯片核。采用混沌的数字计算法计算了双字节不同初始值的周期。由周期对应的不同分组初始值,产生3个离散数字混沌序列并进行同步二进制乘法运算,获得长周期的离散数字混沌序列。实现了数字混沌序列发生器芯片核,给出了芯片核符号结构。对硬件芯片核进行了仿真。结果表明,该芯片核能产生数字混沌序列。研究结果为无线传感器网络安全部件集成提供了可能。

关键词：传感网络节点双字节混沌序列发生器芯片核

A general climatology of categorized Martian ionospheric irregularities

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Science China Earth Sciences 2024年第10期67卷 3302-3325页

作者： xin WAN Jiahao zhong Yongqiang HAO Chao XIONG Hui WANG Yutian CAO Jun CUI Yiwen LIU Qiaoling LI Jiawei KUAI Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China Key Laboratory of Tropical Atmosphere-Ocean System Ministry of EducationZhuhai 519082China Department of Space Physics College of Electronic InformationLuojia LaboratoryWuhan UniversityWuhan 430079China School of Physics and Electronic Information Shangrao Normal UniversityShangrao 334001China School of Petroleum China University of Petroleum-Beijing at KaramayKaramay 834000China College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A climatological survey of Martian ionospheric plasma density irregularities was conducted by exploring the in-situ measurements of the Mars Atmosphere and Volatile EvolutioN(MAVEN) spacecraft. The irregularities were first classified as enhancement, depletion, and oscillation. By checking the simultaneous magnetic field fluctuation, the irregularities have been classified into two types: with or without magnetic signatures. The classified irregularities exhibit diverse global occurrence patterns, as those with magnetic signatures tend to appear near the periphery of the crustal magnetic anomaly(MA), and those without magnetic signatures prefer to appear either inside of the MA or outside of the MA, depending on the type and solar zenith angle. Under most circumstances, the irregularities have a considerable occurrence rate at altitudes above the ionospheric dynamo height(above 200 km), and the magnetization state of the ions seems irrelevant to their occurrence. In addition, the irregularities do not show dependence on magnetic field geometry, except that the enhancement without magnetic signatures favors the vertical field line, implying its equivalence to the localized bulge. Other similarities and discrepancies exist in reference to previous studies. We believe this global survey complements previous research and provides crucial research clues for future efforts to clarify the nature of the Martian ionospheric irregularities.

关键词： Mars MAVEN Ionosphere Ionospheric irregularities Crustal magnetic anomaly Plasma

Cooperative enhancement of mechanical and tribological properties through tailoring TiN transition interface in boron nitride nanosheets reinforced copper composites

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Rare Metals 2024年第10期43卷 5202-5215页

作者： zhong-Hua Li Liang Liu xin You Jian-Hong Yi Rui Bao Ming-Yi Zhu Song Lu Jun-Jun Pai Faculty of Materials Science and Engineering Kunming University of Science and Technology Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and Technology

Strengthening interface bonding between boron nitride nanosheets(BNNS) and copper matrix is an essential prerequisite for exploiting a new generation of copper matrix composites(CMCs) with high strength and wear resistance. Herein, BNNS/Cu composites were fabricated by the powder metallurgy route, matrix-alloying(adding 1.0 wt% Ti) strategy was adopted to improve the interfacial wettability and strengthen interface adhesion. A typical "sandwich"-like multiply interface structure involving TiN transition layers, BNNS and Cu matrix had been well constructed through the rational heat treatment(900℃for 120 min). Additionally, nano-sized TiB whisker was in situ formed in the vicinity of the interface, it had linked the BNNS-Cu-TiN multiply interface, which played a role of "threading the needle" and significantly strengthened the multi-interfaces bonding. This specific interface structure was finely characterized, and the formation mechanism of solid-state interfacial reaction feature was proposed. The results demonstrated that the ultimate tensile strength(UTS) of BNNS/Cu-(Ti)-900℃ increased from 248 to 530 MPa(increased by 114%), and the coefficient of friction(COF) decreased from 0.51 to 0.28 than pure Cu. This work highlights the importance of interface configuration design, which contributes to the development of CMCs with prominent comprehensive properties.

关键词： Boron nitride nanosheets Copper matrix composites Interface structure Mechanical and frictional properties

Enhanced hydrogen evolution performance by 3D ordered macroporous Ru-CoP@NC electrocatalysts

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Rare Metals 2024年第3期43卷 1095-1107页

作者： Chen-Chen Zhang Sheng Wei Li-xian Sun Yi-Fang Ouyang Fen Xu Hai-Liang Chu Hong-GePan Li-xin Chen Xue-Zhang Xiao School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021China School of Materials Science and Engineering Zhejiang UniversityHangzhou310058China

Electrocatalytic water splitting coupled with sustainable energies is identified as an environmentally friendly and renewable strategy to generate high-quality hydrogen for the fuel ***,the main challenge is to develop high performance,low cost and chemically stable electrocatalysts to decline the energy barriers and enhance the sluggish kinetics of hydrogen evolution reaction(HER).Herein,a three-dimensional hierarchically ordered macroporous Ru-CoP@NC electrocatalyst(3DOM Ru-CoP@NC)derived from ordered macro-microporous metal-organic frameworks has been prepared using the precursor@template and double-solvent *** prepared 3DOM Ru-CoP@NC catalyst exhibits an overpotential of 15 mV(j=10 mA·cm^(-2))and a reaction Tafel slope of 38 mV·dec^(-1)in alkaline electrolyte,which are superior to commercial Pt@C ***,the overpotential and reaction Tafel slope of this catalyst in acidic media are 45 mV and 50 mV·dec^(-1),*** outstanding HER activities of 3DOM Ru-CoP@NC catalysts are ascribed to the 3D highly interconnectedreticular nanospaces that can increase effective reaction active *** N dope d carbon framework improves the electronic properties and ***,the strong interaction of Ru and CoP nanoparticles also boosts the HER *** results indicate that 3DOM Ru-CoP@NC catalysts with high catalytic activities have a broad application prospect in the future.

关键词： Hydrogen evolution reaction Template method 3D ordered macroporous Ru-CoP@NC

Study on the occurrence and influencing factors of gastrointestinal symptoms in hemodialysis patients with uremia

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2157-2166页

作者： Dan Yuan Xiao-Qi Wang Feng Shao Jing-Jing Zhou zhong-xin Li Department of Nephrology Beijing Luhe Hospital Affiliated to Capital Medical UniversityBeijing 101100China

BACKGROUND Gastrointestinal symptoms are common in patients with uremia undergoing hemodialysis,and these symptoms seriously affect patients'*** To assess the occurrence and factors influencing gastrointestinal symptoms in patients with uremia undergoing *** We retrospectively selected 98 patients with uremia who underwent regular hemo-dialysis treatment in the blood purification center of our hospital from December 2022 to December *** gastrointestinal symptoms and scores of each dimension were evaluated using the Gastrointestinal Symptom Grading Scale(GSRS).Patients were divided into gastrointestinal symptoms and no gastrointestinal symptom groups according to whether they had gastrointestinal *** factors that may affect gastrointestinal symptoms were identified by single-factor *** logistic regression analysis was performed to identify independent risk factors for gastrointestinal *** Gastrointestinal symptoms included indigestion,constipation,reflux,diarrhea,abdominal pain,and eating disorders,and the total average GSRS score was 1.35±*** study showed that age,number of tablets,dialysis time,glucocorticoid,parathyroid hormone(PTH),combined diabetes mellitus and C-reactive protein(CRP)were independent risk factors for gastrointestinal symptoms in patients with uremia undergoing hemodialysis,whereas body mass index(BMI),hemoglobin(Hb),and urea clearance index were independent protective factors(P<0.05).CONCLUSION Gastrointestinal symptoms are mostly mild in patients with uremia undergoing hemodialysis,most commonly including dyspepsia,eating disorders,and gastroesophageal *** independent influencing factors mainly include the BMI,age,number of pills taken,dialysis time,urea clearance index,Hb,use of glucocorticoids,and thyroid hormone ***,CRP,and diabetes are clinically related factors influencing the occurrence of gastrointestinal symptoms,and targeted prevention can be perform

关键词： Uremic hemodialysis Gastrointestinal symptoms Influencing factors Blood pressure dialysis Chronic renal failure

Rice stripe mosaic virus hijacks rice heading‐related gene to promote the overwintering of its insect vector

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Journal of Integrative Plant Biology 2024年第9期66卷 2000-2016页

作者： Siping Chen xinyi zhong Zhiyi Wang Biao Chen Xiuqin Huang Sipei Xu xin Yang Guohui Zhou Tong Zhang Guangdong Province Key Laboratory of Microbial Signals and Disease Control College of Plant ProtectionSouth China Agricultural UniversityGuangzhou 510642China State Key Laboratory of Green Pesticide South China Agricultural UniversityGuangzhou 510642China

Rice stripe mosaic virus(RSMV)is an emerging pathogen which significantly reduces rice yields in the southern region of *** is transmitted by the leafhopper Recilia dorsalis,which overwinters in rice *** field investigations revealed that RSMV infection causes delayed rice heading,resulting in a large number of green diseased plants remaining in winter rice *** creates a favorable environment for leafhoppers and viruses to overwinter,potentially contributing to the rapid spread and epidemic of the ***,we explored the mechanism by which RSMV manipulates the developmental processes of the rice plant.A rice heading‐related E3 ubiquitin ligase,Heading date Associated Factor 1(HAF1),was found to be hijacked by the RSMV‐encoded *** impairment of HAF1 function affects the ubiquitination and degradation of downstream proteins,HEADING DATE 1 and EARLY FLOWERING3,leading to a delay in rice *** results provide new insights into the development regulation‐based molecular interactions between virus and plant,and highlights the importance of understanding virus‐vector‐plant tripartite interactions for effective disease management strategies.

关键词： HAF1 heading leafhoppers overwintering RSMV

Constructing oxygen deficiency-rich V_(2)O_(3)@PEDOT cathode for high-performance aqueous zinc-ion batteries

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Rare Metals 2024年第2期43卷 635-646页

作者： Dong-Fei Sun Zi-Juan Wang Tian Tian xin Yu Dan-Dan Yu Xiao-zhong Zhou Guo-Fu Ma Zi-Qiang Lei Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceSchool of College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China

Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to the advantages of high safety and environmental *** V_(2)O_(3) is a promising cathode,the strong electrostatic interaction between Zn^(2+) and V_(2)O_(3) crystal,and the sluggish reaction kinetics still limit their application in ***,the oxygen defects rich V_(2)O_(3) with conducive poly(3,4-ethylenedioxythiophene)(PEDOT)shell(V_(2)O_(3)-Od@PEDOT)was fabricated for AZIBs by combining the sulfur-assisted thermal reduction and in-situ polymerization *** introduced oxygen vacancies of V_(2)O_(3)–Od@PEDOT weaken the electrostatic interaction between Zn^(2+) and the host material,improving the interfacial electron transport,while the PEDOT coating enhances the structural stability and conductivity of V_(2)O_(3),thus accelerating the reaction *** on the advantages,V_(2)O_(3)–Od@PEDOT electrode delivers a reversible capacity of 495 mAh·g^(−1) at 0.1 A·g^(−1),good rate capability(189 mAh·g^(−1)at 8.0 A·g^(−1)),and an impressive cycling stability with 90.1%capacity retention over 1000 cycles at 8.0 A·g^(−1).The strategy may provide a path for exploiting the other materials for high performance AZIBs.

关键词： Oxygen defects V_(2)O_(3) PEDOT Electrochemical self-optimization Aqueous zinc-ion batteries

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 481-486页

作者： xin Huang Qian Lu Yue-Wei Zhang Lin Zhang Zhi-zhong Ren Xiao-Wei Yang Ying Liu Rui Tang Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

关键词： Cavernous transformation of the portal vein Classification Direct portal venography Intrahepatic portal venous system