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Spectral Characteristics of LiSrBO_3:Tb^(3+) Green Phosphor

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Chemical Research in Chinese Universities 2009年第5期25卷 610-613页

作者： LI pan-lai WANG zhi-jun YANG zhi-ping GUO Qing-lin College of Physics Science ＆ Technology Hebei University Baoding 071002 P. R. China

LiSrBO3：Tb^3＋ green phosphor was synthesized by means of a solid state reaction and its spectral characteristics were studied. The emission spectrum of LiSrBO3：Tb^3＋ consists of four major bands at 486, 544, 595 and 620 nm under the excitation of near ultraviolet irradiation, which are originated from the ^5Da→^7F6, ^5D4→^7F5, ^5D4→^7F4 and ^5D4→^7F3 characteristic transitions of Tb^3＋, respectively. Monitored at 544 nm, the excitation spectrum of the phosphor extends from 220 nm to 390 nm, with the excitation peaks centered at 242, 277, 368 and 381 nm, respectively. The effect of Tb^3＋ concentration on the emission intensity of LiSrBO3：Tb^3＋ was also investigated. The results show that firstly the intensity increases with increasing Tb^3＋ concentration, reaches a maximum value at 3%（molar fraction） Tb^3＋ and then decreases, showing a concentration self-quenching, whose mechanism is proposed as a d-d interaction based on Dexter theory. The emission intensity of LiSrBO3：Tb^3＋ was enhanced by co-doping Li^＋, Na^＋ and K^＋.

关键词： LiSrBO3:Tb^3+ Green phosphor Spectral characteristics

Degradation of dyestuff wastewater using visible light in the presence of a novel nano TiO_2 catalyst doped with upconversion luminescence agent

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Journal of Environmental Sciences 2005年第5期17卷 727-730页

作者： WANG jun WEN Fu-yu ZHANG Zhao-hong ZHANG Xiang-dong pan zhi-jun ZHANG Lei WANG Lei XU Liang KANG Ping-li ZHANG Peng Department of Chemistry Liaoning University Shenyang 110036 China Department of Environment Liaoning University Shenyang 110036 China Center of Analysis and Test Liaoning University Shenyang 110036 China

A new upconversion luminescence agent, 40CdF2·60BaF2·0.8ErO3, was synthesized and its fluorescent spectra were determined. This upconversion luminescence agent can emit five upconversion fluorescent peaks shown in the fluorescent spectra whose wavelengths are all below 387 nm under the excitation of 488 nm visible light. This upconversion luminescence agent was mixed into nano rutile TiO2 powder by ultrasonic and boiling dispersion and the novel doped nano TiO2 photocatalyst utilizing visible light was firstly prepared. The doped TiO2 powder was charactered by XRD and TEM and its photocatalytic activity was tested through the photocatalytic degradation of methyl orange as a model compound under the visible light irradiation emitted by six three basic color lamps. In order to compare the photocatalytic activities, the same experiment was carried out for undoped TiO2 powder. The degradation ratio of methyl orange in the presence of doped nano TiO2 powder reached 32.5% under visible light irradiation at 20 h which was obviously higher than the corresponding 1.64% in the presence of undoped nano TiO2 powder, which indicate the upconversion luminescence agent prepared as dopant can effectively turn visible lights to ultraviolet lights that are absorbed by nano TiO2 particles to produce the electron-cavity pairs. All the results show that the nano rutile TiO2 powder doped with upconversion luminescence agent is a promising photocatalyst using sunlight for treating the industry dye wastewater in great force.

关键词： upconversion luminescence agent nano TiO2 photocatalytic degradation visible light methyl orange

Luminescence and Site Occupancy of Eu2＋ in Ba2 Ca（BO3）2

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Chinese Physics Letters 2011年第1期28卷 190-192页

作者： LI pan-Lai WANG zhi-jun YANG zhi-Ping GUO Qing-Lin Colleg-e of Physics Science and Technology Hebei University Baoding 071002

A green phosphor Ba2Ca（BOa）2：Eu2＋ was syntheMzed by a high temperature solid-state reaction method under a reductive amosphere,, The luminescence and site occupancy of Eu2＋ in Ba2Ca（BOa）2 are investigated. Ba2Ca（BO3）2：Eu2＋ shows one green band （537nzn） under 400nln near ultraviolet excitation which is suitable for UV LED. Ca2＋ and Ba2＋ ions in Ba2Ca（BO3）2 are replaced by Eu2＋ ions, the Ba2Ca（BO3）2：Eu2＋ shows a dissymmetrical emission band. The influence of Eu2＋ doping concentrations on the emission intensity of Ba2Ca（BOa）2：Eu2＋ is studied. It is found that the emission intensity is influenced by the Eu2＋ concentration and reaches the maxinmm value at 2% Eu2＋, According to the Dexter theory, the concentration quenching mechanisms of Eu2＋ in Ba2 Ca（B03）2 are the d - d interaction,

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Ex vivo expansion and pluripotential differentiation of cryopreserved human bone marrow mesenchymal stem cells

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第2期8卷 136-146页

作者： XIANG Ying ZHENG Qiang JIA Bing-bing HUANG Guo-ping Xu Yu-lin WANG Jin-fu pan zhi-jun School of Life Sciences Zhejiang University Hangzhou 310012 China Department of Orthopedics the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310006 China

This study is aimed at investigating the potentials of ex vivo expansion and pluri-differentiation of cryopreservation of adult human bone marrow mesenchymal stem cells （hMSCs） into chondrocytes, adipocytes and neurocytes. Cryopreserved hMSCs were resuscitated and cultured for 15 passages, and then induced into chondrocytes, adipocytes and neurocytes with corresponding induction medium. The induced cells were observed for morphological properties and detected for expressions of type II collagen, triglyceride or neuron-specific enolase and nestin. The result showed that the resuscitated cells could differentiate into chondrocytes after exposure to transforming growth factor 61 （TGF-~0, insulin-like growth factor I （IGF-I） and vitamin C （Vc）, and uniformly changed morphologically from a spindle-like fibroblastic appearance to a polygonal shape in three weeks. The induced cells were heterochromatic to safranin O and expressed cartilage matrix-procollagenal （If） mRNA. The resuscitated cells cultured in induction medium consisting of dexamethasone, 3-isobutyl-l-methylxanthine, indomethacin and IGF-I showed adipogenesis, and lipid vacuoles accumulation was detectable after 21 d. The resuscitated hMSCs were also induced into neurocytes and expressed nestin and neuron specific endolase （NSE） that were special surface markers associated with neural cells at different stage. This study suggested that the resuscitated hMSCs should be still a population ofpluripotential cells and that it could be used for establishing an abundant bMSC reservoir for further experiment and treatment of various clinical discases.

关键词： Bone marrow mesenchymal stem cells Cryopreservation Expansion Differentiation

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运动性猝死(英文)

中国临床康复 2006年第40期10卷 190-192页

作者：潘志军南京理工大学体育部江苏省南京市210094

目的:探讨和分析运动性猝死的流行病学和病因学特征,为竞技体育和全民健身提供科学有效的预防措施。资料来源:应用计算机检索Medline1982-01/2005-07关于运动性猝死的相关文献,检索词为“exercise/sport,suddendeath”并限定文章的语种... 详细信息

目的:探讨和分析运动性猝死的流行病学和病因学特征,为竞技体育和全民健身提供科学有效的预防措施。资料来源:应用计算机检索Medline1982-01/2005-07关于运动性猝死的相关文献,检索词为“exercise/sport,suddendeath”并限定文章的语种类为English。同时利用计算机检索同期维普中文科技期刊全文数据库关于运动性猝死的相关文献,检索词为“运动、猝死”,限定文章语言种类为中文。资料选择:对资料进行初选,选择与运动有关的猝死文献,排除重复性研究文献以及个案。资料提炼:在63篇文献中,经分类整理,纳入14篇。资料综合:运动性猝死发生率低,进展迅速,与运动项目和运动强度之间没有明显相关,多发生在30～60岁,男性多于女性。病因多为心源性和脑源性猝死,冠状动脉粥样硬化是运动性猝死的一个主要原因。结论:运动性猝死发生率低,存在性别特征,冠状动脉粥样硬化是运动性猝死的一个重要因素。必须加强对运动性猝死流行病学和病因学以及预防措施的研究。

关键词：运动医学猝死流行病学综述文献

基于时域边界元的跨海桥梁下部结构波浪荷载计算方法

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桥梁建设 2022年第6期52卷 66-72页

作者：王东辉潘俊志遆子龙北京交通大学土木建筑工程学院北京100044 中铁大桥局集团有限公司湖北武汉430050 西南交通大学桥梁工程系四川成都610031

为解决当前波浪荷载数值模拟计算量大、效率低的问题,提出桥梁下部结构波浪荷载的时域边界元计算方法。该方法通过选取合适的格林函数,将计算域由三维流域降维为水面和结构物面,采用四边形单元对水面和结构物面进行离散,建立边界元积分... 详细信息

为解决当前波浪荷载数值模拟计算量大、效率低的问题,提出桥梁下部结构波浪荷载的时域边界元计算方法。该方法通过选取合适的格林函数,将计算域由三维流域降维为水面和结构物面,采用四边形单元对水面和结构物面进行离散,建立边界元积分方程,并在时域下逐步求解结构表面的波压力,随后对波压力进行积分,计算结构波浪力。为验证该方法的正确性,将该方法计算结果与Maccamy圆柱波浪力理论解进行比较,并以平潭海峡公铁大桥为背景,对该桥非通航孔桥下部结构的施工钢围堰进行波浪荷载模拟,与现场波压力监测数据进行对比。结果表明:波浪荷载时域边界元计算方法在保证精度的同时,计算效率较高;该方法在实际工程中有较好的适用性;绕射效应对围堰的波压力大小与分布规律有显著影响,在设计阶段应予以充分考虑。

关键词：跨海桥梁下部结构波浪荷载时域边界元方法计算方法数值模拟

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腺苷酸活化蛋白激酶与运动的研究进展

山东体育学院学报 2006年第6期22卷 59-62页

作者：潘志军南京理工大学体育部江苏南京210094

腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)是能量代谢变化的感受器,在能量代谢过程中起着重要调节作用。一些生理刺激能够激活AMPK,激活后的AMPK打开分解代谢途径,同时关闭消耗ATP的通路。急性运动和运动训练能够提高骨... 详细信息

腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)是能量代谢变化的感受器,在能量代谢过程中起着重要调节作用。一些生理刺激能够激活AMPK,激活后的AMPK打开分解代谢途径,同时关闭消耗ATP的通路。急性运动和运动训练能够提高骨骼肌和肝脏组织中AMPK活性,运动训练引起组织中各种适应性反应。AMPK突变则对运动能力产生重要影响。

关键词：腺苷酸活化蛋白激酶亚基亚型活性运动

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有氧运动训练对成年大鼠血清脂质代谢的影响

广州体育学院学报 2000年第2期20卷 43-46页

作者：潘志军南京理工大学体育部南京210094

测定了成年大鼠血清脂蛋白以及脂质过氧化水平和抗氧化酶活性的变化。１２只１２月龄的Ｗｉｓｔａｒ大鼠随机分为对照组和训练组，训练组在跑台上训练８周（每周训练５天，每天训练３０ｍｉｎ，速度为２０ｍ／ｍｉｎ）。结果如下：（１... 详细信息

测定了成年大鼠血清脂蛋白以及脂质过氧化水平和抗氧化酶活性的变化。１２只１２月龄的Ｗｉｓｔａｒ大鼠随机分为对照组和训练组，训练组在跑台上训练８周（每周训练５天，每天训练３０ｍｉｎ，速度为２０ｍ／ｍｉｎ）。结果如下：（１）８周后，训练组体重明显低于对照组；（２）训练组甘油三酯（ＴＧ）、总胆固醇（ＴＣ）变化不明显．低密度脂蛋白（ＬＤＬ—Ｃ）明显低于对照组，高密度脂蛋白（ＨＤＬ－Ｃ）明显高于对照组，Ｐ＜０．０１；（３）训练组血清超氧化物歧化酶（ＳＯＤ）和谷胱甘肽过氧化物酶（ＧＳＨ—Ｐｘ）均高于对照组，丙二醛（ＭＤＡ）含量低于对照组，差异有显著意义．提示有规律的有氧运动训练在调节脂蛋白代谢和抗脂质过氧化方面有显著作用。

关键词：有氧运动训练脂蛋白代谢大鼠脂质过氧化

掺杂半导体β-FeSi_2电子结构及几何结构第一性原理研究

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物理学报 2005年第11期54卷 5308-5313页

作者：潘志军张澜庭吴建生上海交通大学材料科学与工程学院教育部高温材料及测试开放实验室

采用基于第一性原理的密度泛函理论全势线性缀加平面波法,使用广义梯度近似处理交换相关势能,首先计算了β-FeSi2的电子结构及其各元素各亚层电子的能态密度,β-FeSi2的电子能态密度主要由Fe的d层电子和Si的p层电子的能态密度确定;其次... 详细信息

采用基于第一性原理的密度泛函理论全势线性缀加平面波法,使用广义梯度近似处理交换相关势能,首先计算了β-FeSi2的电子结构及其各元素各亚层电子的能态密度,β-FeSi2的电子能态密度主要由Fe的d层电子和Si的p层电子的能态密度确定;其次通过计算不同掺杂系统的总能量确定了掺杂原子在β-FeSi2中的置换位置,在β-FeSi2中,Co置换FeⅡ位置的Fe原子,Al置换SiⅠ位置的Si原子,这种择位置换与现有的计算结果完全一致;最后计算了Fe1-xCoxSi2和Fe(Si1-xAlx)2的电子结构,对它们的电子结构特征进行了分析,并探讨了电子结构对其热电性能(塞贝克系数、电传输及热传输性能)的影响.

关键词：第一性原理,电子结构,热电性能,FeSi2 β-FeSi2 电子结构第一性原理几何结构掺杂半导体计算结果密度泛函理论能态密度