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基于冷分子离子HD^(+)振转光谱的精密测量

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物理学报 2024年第20期73卷 67-82页

作者：张乾煜白文丽敖致远丁彦皓彭文翠何胜国童昕中国科学院精密测量科学与技术创新研究院波谱与原子分子物理国家重点实验室武汉430071 中国科学院大学北京100049 武汉量子技术研究院武汉430074

由一个质子、一个氘核和一个电子组成的氢分子离子“HD^(+)”是最简单的异核双原子分子,其有着丰富的、可精确计算和测量的振转跃迁谱线.通过HD^(+)振转光谱实验测量和理论计算的对比,可实现物理常数的精确确定,量子电动力学理论的检验... 详细信息

由一个质子、一个氘核和一个电子组成的氢分子离子“HD^(+)”是最简单的异核双原子分子,其有着丰富的、可精确计算和测量的振转跃迁谱线.通过HD^(+)振转光谱实验测量和理论计算的对比,可实现物理常数的精确确定,量子电动力学理论的检验,并开启了超越标准模型新物理的探寻.目前,HD^(+)的振转跃迁频率确定的相对精度已经进入了10^(-12)量级,并由此获得了当前最高精度的质子电子质量比,相对精度达到20 ppt(1 ppt=10^(-12)).本文全面介绍了目前HD^(+)振转光谱的研究现状与理论背景,阐述了基于Be^(+)离子协同冷却HD^(+)分子离子的高精度振转光谱测量方法,包括Be^(+)离子和HD^(+)分子离子的产生与囚禁,HD^(+)外态冷却与内态制备,双组分库仑晶体中HD^(+)数目的确定,以及HD^(+)振转跃迁的探测.最后,文章展望了进一步提高频率测量精度的光谱前沿技术,及同位素氢分子离子的振转光谱在未来研究中的发展前景.

关键词：振转光谱 HD^(+)分子离子协同冷却

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两种常见慢性病共病的影响因素分析

现代预防医学 2024年第9期51卷 1568-1573+1619页

作者：李瑞雷伟摆文丽李寅臻张亚洲张眉芮东升王奎石河子大学医学院预防医学系重要新发传染病防控与公共卫生安全兵团重点实验室

目的了解两种常见慢性病的危险因素，以期为慢性病共病预防和政府的疾病投入提供依据。方法采用中国健康与养老追踪调查（China health and retirement longitudinal study,CHARLS）2011—2018年四次随访数据。纳入高血压和风湿病或... 详细信息

目的了解两种常见慢性病的危险因素，以期为慢性病共病预防和政府的疾病投入提供依据。方法采用中国健康与养老追踪调查（China health and retirement longitudinal study,CHARLS）2011—2018年四次随访数据。纳入高血压和风湿病或关节炎、胃部疾病和风湿病或关节炎两种慢性病共病人群2 992和1 952例。采用Cox比例风险模型和共享脆弱模型分析共病发生影响因素。结果高血压和风湿病或关节炎人群：居住在农村（HR=1.367,95%CI:1.096～1.705）、高年龄组（HR=1.342,95%CI:1.013～1.778）、肥胖（HR=2.424,95%CI:1.790～3.283）、首发病是风湿病或关节炎（HR=3.797,95%CI:3.059～4.713）、其他慢性病数量大于1(HR=2.694,95%CI:2.042～3.555)人群发生共病的可能性更高，高受教育水平（HR=0.766,95%CI:0.594～0.988）人群发生共病可能性较低，共享脆弱模型拟合程度优于Cox模型。胃部疾病和风湿病或高血压人群：高年龄组（HR=0.392,95%CI:0.240～0.640）、受教育水平高（HR=0.667,95%CI:0.461～0.964）、超重（HR=0.720,95%CI:0.540～0.96）人群中共病发生的可能性较低，健康自评消极（HR=1.409,95%CI:1.038～1.912）、偏瘦（HR=1.935,95%CI:1.198～3.126）、慢性病数量大于1人群（HR=2.339,95%CI:1.644～3.328）发生共病可能性更高，该人群中两模型结果无太大差异。结论层次生存数据中，共享脆弱模型拟合效果高于传统模型。高血压和风湿病或关节炎共病人群中高年龄组、肥胖、首发病是风湿病或关节炎人群发病风险升高，高年龄组、超重人群中胃部疾病和风湿病或关节炎共病发生可能性更低。因此慢性病共病的预防应针对不同共病组合，分别确定高危人群，进行不同的干预行为，准确进行医疗资源的投入，降低政府的疾病负担。

关键词：慢性病共病 CHARLS数据影响因素分析层次结构数据

The Uniqueness of Decomposition of Symplectic Ternary Algebras with Trivial Center

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Journal of Mathematical Research and Exposition 2010年第3期30卷 423-428页

作者： Xi Mei bai wen li liU College of Mathematics and Computer Hebei University Hebei 071002 P. R. China

In this paper, the authors define the center of a Symplectic ternary algebra, and investigate the relationship between the center of a Symplectic ternary algebra and that of the lie triple system associated with it. As an application of the relationship, the unique decomposition theorem for Symplectic ternary algebras with trivial center is obtained.

关键词： Symplectic ternary algebras lie triple system center U-endomorphism.

不同药物对祁连山北麓草原蝗虫混合种群的防效评价

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中国牛业科学 2024年第1期50卷 54-57页

作者：秦丽萍白文丽罗天旭薛德生李晓鹏武威市草原工作站甘肃武威733000 古浪县草原工作站甘肃古浪733100 甘肃省草原技术推广总站甘肃兰州730000

为科学筛选适宜的草原蝗虫防治药物和施药浓度,本试验比较了3种不同药剂、不同施药浓度对草原蝗虫的防治效果。结果表明:试验区蝗虫混合虫口密度约为15头/m^(2),3种药剂对草原蝗虫均有较好的防治效果,其中,4.5%高效氯氰菊酯起效最快,施... 详细信息

为科学筛选适宜的草原蝗虫防治药物和施药浓度,本试验比较了3种不同药剂、不同施药浓度对草原蝗虫的防治效果。结果表明:试验区蝗虫混合虫口密度约为15头/m^(2),3种药剂对草原蝗虫均有较好的防治效果,其中,4.5%高效氯氰菊酯起效最快,施药3d后其防治效果就达到90%以上,但是7d后,300ml/hm^(2)的1.8%阿维菌素和750ml/hm^(2)的1.3%苦参碱两个剂量的防治效果与600ml/hm^(2)的4.5%高效氯氰菊酯的防治效果差异不显著(P>0.05)。为保证防治效果和生态安全性,建议在一般防治中使用苦参碱和阿维菌素,推荐使用剂量为750ml/hm^(2)和300ml/hm^(2),在危害严重时使用高效氯氰菊酯,推荐使用剂量为600ml/hm^(2)。

关键词：温性草原蝗虫防治效果

Research on ECMS Based on Segmented Path Braking Energy Recovery in a Fuel Cell Vehicle

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Energy Engineering 2024年第1期121卷 95-110页

作者： wen Sun Meijing li Guoxiang li Ke Sun Shuzhan bai School of Energy and Power Engineering Shandong UniversityJinan250061China Automotive Research Institute China National Heavy Duty Truck Group Co.Ltd.Jinan250061China

Proton exchange membrane fuel cells are widely regarded as having the potential to replace internal combustion engines in *** fuel cells cannot recover energy and have a slow dynamic response,they need to be used with different power *** efficient energy management strategies to achieve excellent fuel economy is the goal of *** paper proposes an adaptive equivalent fuel minimum consumption strategy(AECMS)to solve the problem of the poor economy of the whole vehicle caused by the wrong selection of equivalent factors(EF)in traditional *** this method,the kinematics interval is used to update the equivalent factor by considering the penalty term of energy recovery on SOC ***,the optimized equivalent factor is substituted into the optimization objective function to achieve efficient energy *** results under the New European Driving Cycle show that compared with the traditional ECMS based on fixed SOC benchmarks,the proposed method improves fuel economy by 1.7%while ensuring vehicle power and increases SOC by 30%.

关键词： Fuel cell PEMFC electric vehicle equivalent consumption minimization strategy

Automatic velocity picking based on optimal key points tracking algorithm

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Petroleum Science 2024年第2期21卷 903-917页

作者： Yong-Hao Wang wen-Kai Lu Song-bai Jin Yang li Yu-Xuan li Xiao-Feng Gu The Institute for Artificial Intelligence(THUAI) Tsinghua UniversityBeijing100084China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China

Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost.

关键词： Velocity picking Multi-object tracking Density clustering Kalman filter

河西走廊荒漠草原白茨粗角萤叶甲发生及生物防治研究

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中国牛业科学 2024年第2期50卷 42-46页

作者：白文丽秦丽萍罗天旭冯兆林马维新武威市草原工作站甘肃武威733000 民勤县草原工作站武威733399

在调查白茨粗角萤叶甲各虫态、虫龄的数量、活动、为害等有关生物学习性的同时,选用1.8%阿维菌素、1.2%烟碱苦参碱乳油、3%高渗苯氧威、25%灭幼脲3号悬浮剂、50000 IU/mg-1苏云金杆菌等5种生物药剂,进行防效对比试验,结果表明:白茨粗角... 详细信息

在调查白茨粗角萤叶甲各虫态、虫龄的数量、活动、为害等有关生物学习性的同时,选用1.8%阿维菌素、1.2%烟碱苦参碱乳油、3%高渗苯氧威、25%灭幼脲3号悬浮剂、50000 IU/mg-1苏云金杆菌等5种生物药剂,进行防效对比试验,结果表明:白茨粗角萤叶甲在民勤地区1年可发生3代,应在5月中下旬越冬成虫产卵盛期或者7月中下旬2代幼虫期开展防治。综合考虑经济成本和防治效果,实际防治中可轮换使用以上5中药剂。危害程度较高时推荐使用1.2%烟碱苦参碱2000倍液和3%高渗苯氧威3000倍液,危害程度较低时可使用1.8%阿维菌素1000倍液、50000 IU/mg-1苏云金杆菌1000倍液或者25%灭幼脲3号1000倍液。

关键词：荒漠草原白茨粗角萤叶甲生物防治

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Ultrahigh strength and uniform corrosion in Zn-li alloys through ultrahigh pressure supersaturated solid solution treatment for biodegradable orthopedic applications

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Rare Metals 2024年第10期43卷 5284-5304页

作者： Wan-Ying li Yi-Long Dai wen-Hao Cai Si-Han lin lin Guo De-Chuang Zhang Yuncang li Cuie wen School of Materials Science and Engineering Xiangtan University Department of Prosthodontics Shanghai Ninth People′s HospitalShanghai Jiao Tong University Key Laboratory of Low Dimensional Materials&Application Technology Ministry of EducationXiangtan University School of Engineering RMIT UniversityMelbourne

Zn-li alloys are considered promising candidate materials for biodegradable orthopedic implant applications due to their high mechanical performance and good ***,the presence of a large number of second-phase particles in this class of Zn alloys can lead to severe localized degradation due to micro-galvanic corrosion,which is detrimental to the mechanical integrity of the alloys during tissue healing in the human *** this study we report ultrahigh strength,uniform corrosion,good cytocompatibility,and effective antibacterial ability in Zn-x li（x=0.3,0.5,0.7;wt%） alloys achieved through supersaturated solid solution treatment （SSST） at 375℃ under ultrahigh pressure of 3 GPa.A high concentration of β-liZn4phases coexisted with the-Zn matrix in the as-cast Zn-x li alloys,whereas almost all the li dissolved into the-Zn matrix of SSST *** yield strength was 437 MPa for SSST Zn-0.3li,592 MPa for SSST Zn-0.5 li and 686 MPa for SSST *** SSST Zn-li alloys showed uniform degradation with remarkably reduced degradation rates compared to their as-cast *** 25% concentration extracts of the Zn-x li alloys demonstrated no cytotoxicity toward MC3T3-E1 cells,and the alloys exhibited effective antibacterial ability agains methicillin-resistant staphylococcus aureus.

关键词： Corrosion behavior Mechanical property Supersaturated solid solution treatment (SSST) Ultrahigh pressure Zn-li alloy

Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-wen Lu Hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H *** milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)*** 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene