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Persistent luminescence from Y3Al2Ga3O12 doped with Ce3+ and Cr3+ after X-ray and blue light irradiation

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journal of Rare Earths 2019年第11期37卷 1200-1205页

作者： V.Boiko j.zeler M.Markowska z.dai A.Gerus P.Bolek E.zych D.Hreniak Institute of Low Temperature and Structure Research Polish Academy of SciencesOkolna 2PL-50-422 WroclawPoland Faculty of Chemistry University of WroclawF.Joliot-Curie 14PL-50-383 WroclawPoland

The persistent luminescence(PersL)dependence on the dopants and derived mechanism of trapping and de-trapping processes were investigated in Y3Al2Ga3O12(YAGG)based nanophosphor,doped with Ce^3+and/or Cr^3+.It is found that the presence of Cr^3+ions produce electron and hole traps and capture suitable charge after X-ray *** effect of irradiation on the carriers trapping and their pathways after excitation was studied by means of thermo luminescence *** the other hand,for blue light irradiation the mechanism seems to be *** the latter case,the Ce^3+ions,having the position of energy levels in the conduction band,become sensitizers for the electrons and main emission centres for the PersL(de-trapping process goes through Ce^3+).

关键词： Persistent luminescence Thermoluminescence YAGG nanophosphors Lanthanides X-ray Blue-light irradiation

Contamination by Organochlorine Pesticides in the Estuaries of Southeast China

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Chemical Research in Chinese Universities 2002年第2期18卷 153-160页

作者： z.L.zhang H.S.Hong j.L.zhou M.H.dai K.Maskaouib W.Q.Chen Department of Environmental Science and Engineering Tsinghua POPs Research CentreTsinghua UniversityBeijing 100084China Key Laboratory of Marine Environmental Science of Ministry of Education Environmental Science Research CentreXiamen Universi-tyXiamen 361005China School of Chemistry Physics and Environmental ScienceUniversity of SussexFalmerBrighton BN19QJUK

Persistent organic pollutants(POPs) such as organochlorine pesticides are of global concern due to their widespread occurrence and persistence. This paper reports recent research studying the distribution and fate of organochlorine pesticides in the jiulong River, the Minjiang River and the Pearl River estuaries in Southeast China. Eighteen organochlorine pesticides were extracted from water, pore water and sediment samples, followed by analysis by GC ECD. The results showed that the contamination levels were similar in these three estuaries. The levels of the total organochlorine pesticides in porewater were significantly higher than those in surface water, due to the high affinity of these hydrophobic compounds for sediment phase. Among the hexachlorocyclohexane(HCH) compounds, β HCH was found to be the most important isomer. The analysis of 1,1,1 trichloro 2,2 bis chlorophenyl ethane(DDT) and its metabolites showed that 1,1 dichloro 2[ o chlorophenyl] 2[ p chlorophenyl] ethylene(DDE) was dominant in the group.

关键词： Organochlorine insecticides DDT Lindane jiulong River Estuary Minjiang River Estuary Pearl River Estuary Water Sediment

Dixon MRI对健康成年人背部伸肌年龄和性别相关变异的多参数定量评估

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国际医学放射学杂志 2024年第2期 247-248页

作者： P.z.Chen z.zhou L.Sun X.K.Yu K.Li j.Li 王俊

摘要目的使用Dixon MRI研究健康成人年龄相关性背伸肌退变的性别差异，并分析肌肉定量参数与背肌力的关系。方法纳入105名健康受试者行腰椎Dixon MRI检查。量

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Associations between health-related fitness and patient-reported symptoms in newly diagnosed breast cancer patients

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journal of Sport and Health Science 2024年第6期13卷 851-862页

作者： Ki-Yong An Fernanda z.Arthuso Myriam Filion Spencer j.Allen Stephanie M.Ntoukas Gordon j.Bell jessica McNeil Qinggang Wang Margaret L.McNeely jeff K.Vallance Lin Yang S.Nicole Culos-Reed Leanne Dickau john R.Mackey Christine M.Friedenreich Kerry S.Courneya Faculty of Kinesiology Sportand RecreationCollege of Health SciencesUniversity of AlbertaEdmonton T6G 2H9Canada Department of Kinesiology School of Health and Human SciencesUniversity of North Carolina at GreensboroGreensboroNC 27412USA Department of Cancer Epidemiology and Prevention Research Cancer Care AlbertaAlberta Health ServicesCalgary T2S 3C3Canada Faculty of Rehabilitation Medicine University of AlbertaEdmonton T6G 2H9Canada Faculty of Health Disciplines Athabasca UniversityAthabasca T9S 3A3Canada Department of Oncology Cumming School of MedicineUniversity of CalgaryCalgary T2N 4N1Canada Faculty of Kinesiology University of CalgaryCalgary T2N 1N4Canada Faculty of Medicine and Dentistry University of AlbertaEdmonton T6G 2H9Canada

Background:Newly diagnosed breast cancer patients experience symptoms that may affect their quality of life,treatment outcomes,and *** and managing breast cancer-related symptoms soon after diagnosis is *** purpose of this study was to investigate the associations between health-related fitness(HRF)and patient-reported symptoms in newly diagnosed breast cancer ***:This study utilized baseline data from the Alberta Moving Beyond Breast Cancer Cohort Study that were collected within 90 days of *** measures included peak cardiopulmonary fitness(peak volume of oxygen consumption(VO_(2peak))),maximal muscular strength and endurance,flexibility,and body *** measures included depression,sleep quality,and *** multivariable logistic regression was performed for ***:Of 1458 participants,51.5%reported poor sleep quality,26.5%reported significant fatigue,and 10.4%reported moderate *** multivariable-adjusted models,lower relative VO_(2peak)was independently associated with a greater likelihood of all symptom measures,including moderate depression(p<0.001),poor sleep quality(p=0.009),significant fatigue(p=0.008),any symptom(p<0.001),and multiple symptoms(p<0.001).VO_(2peak)demonstrated threshold associations with all symptom measures such that all 3 lower quartiles exhibited similar elevated risk compared to the highest *** strength of the threshold associations varied by the symptom measure with odds ratios ranging from-1.5 for poor sleep quality to-3.0 for moderate depression and multiple ***,lower relative upper body muscular endurance was also independently associated with fatigue in a dose-response manner(p=0.001),and higher body weight was independently associated with poor sleep quality in an inverted U pattern(p=0.021).Conclusion:Relative VO_(2peak)appears to be a critical HRF component associated with multiple patient-reported symptoms in newly diag

关键词： Breast cancer Fatigue Depression Sleep quality Cardiorespiratory fitness

Partition method and experimental validation for impact dynamics of flexible multibody system

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Acta Mechanica Sinica 2018年第3期34卷 482-492页

作者： j.Y.Wang z.Y.Liu j.z.Hong School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University

The impact problem of a flexible multibody system is a non-smooth, high-transient, and strong-nonlinear dynamic process with variable boundary. How to model the contact/impact process accurately and efficiently is one of the main difficulties in many engineering applications. The numerical approaches being used widely in impact analysis are mainly from two fields： multibody system dynamics （MBS） and computational solid mechanics （CSM）. Approaches based on MBS provide a more efficient yet less accurate analysis of the contact/impact problems, while approaches based on CSM are well suited for particularly high accuracy needs, yet require very high computational effort. To bridge the gap between accuracy and efficiency in the dynamic simulation of a flexible multibody system with contacts/impacts, a partition method is presented considering that the contact body is divided into two parts, an impact region and a non-impact region. The impact region is modeled using the finite element method to guarantee the local accuracy, while the non-impact region is modeled using the modal reduction approach to raise the global efficiency. A three-dimensional rod-plate impact experiment is designed and performed to validate the numerical results. The principle for how to partition the contact bodies is proposed： the maximum radius of the impact region can be estimated by an analytical method, and the modal truncation orders of the non-impact region can be estimated by the highest frequency of the signal measured. The simulation results using the presented method are in good agreement with the experimental results. It shows that this method is an effec-rive formulation considering both accuracy and efficiency. Moreover, a more complicated multibody impact problem of a crank slider mechanism is investigated to strengthen this conclusion.

关键词： Partition method Impact dynamics Experimental investigation Efficiency and accuracy Partition principle

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.D.james j.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Distributed Secondary Control Based on Dynamic Diffusion Algorithm for Current Sharing and Average Voltage Regulation in DC Microgrids

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journal of Modern Power Systems and Clean Energy 2024年第2期12卷 597-607页

作者： Dawei Liao Fei Gao Daniel j.Rogers Wentao Huang Dong Liu Houjun Tang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Engineering Science University of OxfordOxford OX12JDU.K. IEEE

This paper introduces a distributed secondary control scheme for achieving current sharing and average voltage regulation objectives in a DC *** proposed scheme employs a dynamic diffusion algorithm(DDA)instead of the consensus algorithm to enable distributed communication among *** help understand DDA,the relation of DDA and other diffusion algorithms is discussed in detail and its superiority is shown by comparison with diffusion and consensus ***,considering the discrete nature and different sampling time of the digital controller and communication network,a z-domain model of the entire DC microgrid is *** influence of communication and secondary control parameters on the system stability is *** on the established model,the tolerable communication rates are ***-time simulations conducted on the OPAL-RT platform validate the effectiveness of the proposed scheme,showcasing its advantages in terms of convergence speed and stability.

关键词： Cooperative control DC microgrid diffusion algorithm discrete-time modeling distributed secondary control

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甘肃省熊蜂分布特征及其影响因素

中国蜂业 2024年第8期15卷 13-13页

作者：安建东 Naeem M Chen H Li W Hughes AC Williams PH Bashir NH Miao z Huang j An j 中国农业科学院蜜蜂研究所

近日，中国农业科学院蜜蜂研究所联合曲靖师范学院等单位科研人员发现甘肃省熊蜂呈现四大生物地理区系，净初级生产力是影响熊蜂多样性分布的最主要因素。该研究成果在线发表在《昆虫(Insects)》上。熊蜂是众多植物的传粉者，在陆地生... 详细信息

近日，中国农业科学院蜜蜂研究所联合曲靖师范学院等单位科研人员发现甘肃省熊蜂呈现四大生物地理区系，净初级生产力是影响熊蜂多样性分布的最主要因素。该研究成果在线发表在《昆虫(Insects)》上。熊蜂是众多植物的传粉者，在陆地生态系统中发挥着十分重要的作用。明确影响熊蜂分布的因素对于熊蜂多样性保护至关重要。

关键词： Gansu biodiversity biogeographic regionalization bumblebees canonical correspondence analysis

KINETICS OF TEMPER EMBRITTLEMENT IN 2.25Cr-1Mo STEEL USED FOR HOT-WALL HYDROFINING REACTORS

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Acta Metallurgica Sinica(English Letters) 2004年第2期17卷 139-146页

作者： j.z.Tan CollegeofMechanicalandPowerEngineering NanjingUniversityofTechnologyNanjing210009China

Based on the theory of grain boundary segregation, a kinetics model of temper em-brittlement caused by long-term service for hot-wall hydrofining reactors was *** kinetics model was applied to phosphorus (P) segregation in 2.25Cr-1Mo steelused for a hot-wall hydrofining reactor, and the kinetics of grain boundary segrea-tion of impurity P in the steel exposed to the process environment of the hydrofiningreactor was calculated on the basis of the model. The Auger electron spectroscopytest was performed in order to determine the grain boundary concentration of P. Theexperimental result is agreement with the theoretical calculated data. The results showthat the kinetics equation is reasonable for predicting the levels of grain boundarysegregation of impurity P in 2.25Cr-1Mo steel used for hot-wall hydrofining reactors.

关键词： hydrofining reactor 2.25Cr-1Mo steel temper embrittlement kinetics