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A Qualitative Look at Decreasing Barriers to Receiving Uninterrupted Care for People Living with HIV in Rural Southern Georgia
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作者 Joshua M. Kies 《Open Journal of Nursing》 2024年第8期447-458,共12页
Early linkage to antiretroviral therapy (ART) after HIV diagnosis extends life. Low socioeconomic populations with HIV face regional concerns that inhibit early treatment. Barriers include religious-based stigma, lack... Early linkage to antiretroviral therapy (ART) after HIV diagnosis extends life. Low socioeconomic populations with HIV face regional concerns that inhibit early treatment. Barriers include religious-based stigma, lack of local treatment facilities, fear of discovery and purposeful secrecy fostering increased HIV transmission and decreased ART adherence. This ethnographic qualitative study employed semi-structured interviews with 10 health care providers (HCP) and 10 people living with HIV (PLWH) to discover methods to streamline care and increase medication adherence. Clients perceive enhanced care when they are active participants in treatment. HCPs reported positive health outcomes when there was active multidisciplinary communication. Obstacles included a lack of consistent medication assistance programs, homelessness, and limited access to specialized services. There is a need for further investigation on how to provide individualized, holistic treatment to a population of patients with extremely limited federal funding in a geographic region where religious stigma surrounding HIV is widespread. 展开更多
关键词 Antiretroviral Treatment (ART) Barriers COMPLIANCE HIV RURAL
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Differences between lower extremity joint running kinetics captured by marker-based and markerless systems were speed dependent
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作者 Hui Tang Barry Munkasy Li Li 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期569-578,共10页
Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion anal... Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as running.Applied studies using markerless systems in clinical and sports settings are still lacking.Thus,the present study compared running biomechanics estimated by marker-based and markerless systems.Given running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating study.Methods:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic methods.Time series analysis and statistical parametric mapping were used to determine system differences.Results:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most cases.Conclusion:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused attention.Based on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless vs.marker-based systems.The differences were amplified by running speed. 展开更多
关键词 BIOMECHANICS Motion capture GAIT Statistical parametric mapping
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Assessment of Municipal Solid Waste Management in the Farmgate Area of Dhaka North City Corporation
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作者 Seyedali Mirmotalebi Shoeb Rahman +1 位作者 Mayida Rubya Tithi Imran Khan Apu 《World Journal of Engineering and Technology》 2024年第1期1-23,共23页
This investigation is focused on conducting a thorough analysis of Municipal Solid Waste Management (MSWM). MSWM encompasses a range of interdisciplinary measures that govern the various stages involved in managing un... This investigation is focused on conducting a thorough analysis of Municipal Solid Waste Management (MSWM). MSWM encompasses a range of interdisciplinary measures that govern the various stages involved in managing unwanted or non-utilizable solid materials, commonly known as rubbish, trash, junk, refuse, and garbage. These stages include generation, storage, collection, recycling, transportation, handling, disposal, and monitoring. The waste materials mentioned in this context exhibit a wide range of items, such as organic waste from food and vegetables, paper, plastic, polyethylene, iron, tin cans, deceased animals, byproducts from demolition activities, manure, and various other discarded materials. This study aims to provide insights into the possibilities of enhancing solid waste management in the Farmgate area of Dhaka North City Corporation (DNCC). To accomplish this objective, the research examines the conventional waste management methods employed in this area. It conducts extensive field surveys, collecting valuable data through interviews with local residents and key individuals involved in waste management, such as waste collectors, dealers, intermediate dealers, recyclers, and shopkeepers. The results indicate that significant amounts of distinct waste categories are produced daily. These include food and vegetable waste, which amount to 52.1 tons/day;polythene and plastic, which total 4.5 tons/day;metal and tin-can waste, which amounts to 1.4 tons/day;and paper waste, which totals 5.9 tons/day. This study highlights the significance of promoting environmental consciousness to effectively shape the attitudes of urban residents toward waste disposal and management. It emphasizes the need for collaboration between authorities and researchers to improve the current waste management system. 展开更多
关键词 Solid Waste Management Dhaka North City Corporation Sustainable Growth Integrated Waste Management Practice Waste Recycling
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THE EXISTENCE AND STABILITY OF NORMALIZED SOLUTIONS FOR A BI-HARMONIC NONLINEAR SCHR?DINGER EQUATION WITH MIXED DISPERSION
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作者 罗庭健 郑世骏 朱世辉 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期539-563,共25页
In this paper,we study the ground state standing wave solutions for the focusing bi-harmonic nonlinear Schrodinger equation with aμ-Laplacian term(BNLS).Such BNLS models the propagation of intense laser beams in a bu... In this paper,we study the ground state standing wave solutions for the focusing bi-harmonic nonlinear Schrodinger equation with aμ-Laplacian term(BNLS).Such BNLS models the propagation of intense laser beams in a bulk medium with a second-order dispersion term.Denoting by Qpthe ground state for the BNLS withμ=0,we prove that in the mass-subcritical regime p∈(1,1+8/d),there exist orbit ally stable ground state solutions for the BNLS when p∈(-λ0,∞)for someλ0=λ0(p,d,‖Qp‖L2)>0.Moreover,in the mass-critical case p=1+8/d,we prove the orbital stability on a certain mass level below‖Q*‖L2,provided thatμ∈(-λ1,0),where■and Q*=Q1+8/d.The proofs are mainly based on the profile decomposition and a sharp Gagliardo-Nirenberg type inequality.Our treatment allows us to fill the gap concerning the existence of the ground states for the BNLS when p is negative and p∈(1,1+8/d]. 展开更多
关键词 elliptic equations bi-harmonic operator normalized solutions profile decomposition
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Dynamic Cell Modeling for Accurate SOC Estimation in Autonomous Electric Vehicles
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作者 Qasim Ajao Lanre Sadeeq 《Journal of Power and Energy Engineering》 2023年第8期1-15,共15页
This paper presents findings on dynamic cell modeling for state-of-charge (SOC) estimation in an autonomous electric vehicle (AEV). The studied cells are Lithium-Ion Polymer-based with a nominal capacity of around 8 A... This paper presents findings on dynamic cell modeling for state-of-charge (SOC) estimation in an autonomous electric vehicle (AEV). The studied cells are Lithium-Ion Polymer-based with a nominal capacity of around 8 Ah, optimized for power-needy applications. The AEV operates in a harsh environment with rate requirements up to ±25C and highly dynamic rate profiles, unlike portable-electronic applications with constant power output and fractional C rates. SOC estimation methods effective in portable electronics may not suffice for the AEV. Accurate SOC estimation necessitates a precise cell model. The proposed SOC estimation method utilizes a detailed Kalman-filtering approach. The cell model must include SOC as a state in the model state vector. Multiple cell models are presented, starting with a simple one employing “Coulomb counting” as the state equation and Shepherd’s rule as the output equation, lacking prediction of cell relaxation dynamics. An improved model incorporates filter states to account for relaxation and other dynamics in closed-circuit cell voltage, yielding better performance. The best overall results are achieved with a method combining nonlinear autoregressive filtering and dynamic radial basis function networks. The paper includes lab test results comparing physical cells with model predictions. The most accurate models obtained have an RMS estimation error lower than the quantization noise floor expected in the battery-management-system design. Importantly, these models enable precise SOC estimation, allowing the vehicle controller to utilize the battery pack’s full operating range without overcharging or undercharging concerns. 展开更多
关键词 Autonomous Electric Vehicle Modeling Battery Model Battery Management Systems (BMS) Lithium Polymer State of Charge Kalman-Filter
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金属离子表面修饰对纳米ZnS∶Mn^(2+)溶胶发光性质的影响 被引量:10
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作者 陈力 张家骅 +2 位作者 骆永石 吕少哲 王笑军 《发光学报》 EI CAS CSCD 北大核心 2004年第1期72-76,共5页
利用胶体化学共沉淀方法制备了纳米ZnS∶Mn2 + 乙醇溶胶 ,观察到Zn2 + 的引入对内部Mn2 + 的4T1→6A1跃迁的 5 80nm橙色发光有激活作用 ,而外加的Mn2 + 对该橙色发光有猝灭作用。Zn2 + 的吸附通过形成单层ZnS壳 ,减少了表面猝灭中心 ,... 利用胶体化学共沉淀方法制备了纳米ZnS∶Mn2 + 乙醇溶胶 ,观察到Zn2 + 的引入对内部Mn2 + 的4T1→6A1跃迁的 5 80nm橙色发光有激活作用 ,而外加的Mn2 + 对该橙色发光有猝灭作用。Zn2 + 的吸附通过形成单层ZnS壳 ,减少了表面猝灭中心 ,从而使发光强度增加 ,这种表面猝灭中心最有可能是来自表面S2 -孤对电子的悬空键。Mn2 + 的猝灭过程不能用纯粹动态的猝灭过程来描述 ,Mn2 + 本身很可能就是橙光的猝灭中心。考虑到Mn2 + 在颗粒表面上的按泊松分布 ,并假设单个Mn2 + 能 1 0 0 %猝灭Mn2 + 5 80nm发射 ,理论与实验数据很好地符合。通过对猝灭数据的拟合 ,估算出的颗粒尺寸小于用有效质量近似模型算得的 3 .1nm ,分析了可能的原因。 展开更多
关键词 金属离子 表面修饰 光致发光 硫化锌溶胶 锰离子 激活 猝灭中心 纳米颗粒
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Pr^(3+)掺杂的LaF_3纳米微晶氟氧化物玻璃陶瓷的激光选择激发 被引量:7
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作者 李庆福 黄世华 +3 位作者 吕少哲 刘舒曼 王笑军 W.M.Yen 《中国稀土学报》 CAS CSCD 北大核心 2002年第6期526-530,共5页
研究了Pr3+掺杂纳米晶 氟氧化物玻璃陶瓷的光谱性质,选择激发光谱分辨了氟氧化物玻璃陶瓷和其中的LaF3纳米微晶内的Pr3+离子,可以看到LaF3纳米微晶 氟氧化物玻璃陶瓷体系在光谱上未表现出明显的界面效应,这对良好的发光性质可能是一种... 研究了Pr3+掺杂纳米晶 氟氧化物玻璃陶瓷的光谱性质,选择激发光谱分辨了氟氧化物玻璃陶瓷和其中的LaF3纳米微晶内的Pr3+离子,可以看到LaF3纳米微晶 氟氧化物玻璃陶瓷体系在光谱上未表现出明显的界面效应,这对良好的发光性质可能是一种有利因素。纳米微粒小的尺寸和大的比表面增加了掺杂离子的局域环境的离散性,使纳米微粒中谱线的非均匀线宽比体材料中大,且随粒径减小而增加。掺杂离子在微晶中富集,或在界面附近富集,提高了微晶中或微晶内局部范围中的浓度,增加了交叉迟豫的几率,出现浓度猝灭,因此Pr3+离子在LaF3中的富集而引起的浓度猝灭是发光能级寿命缩短的主要原因。 展开更多
关键词 LAF3 纳米微晶 稀土 氟氧化物玻璃陶瓷 三价镨离子 掺杂 氟化镓 发光 激发光谱
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氯盐对水泥混凝土强度与防冰效率的试验研究 被引量:2
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作者 曹林涛 Xie Zhaoxing +1 位作者 万红军 张小龙 《中外公路》 北大核心 2013年第1期237-239,共3页
以盐溶液外部浸泡模拟混凝土表面防冰,以内部掺加盐分模拟混凝土内部防冰。通过抗压与弯拉试验分析了2种氯盐施加方式对混凝土强度的影响;又通过室内冻结试验分析了氯盐施加方式对防冰效率的影响。结果表明:内部防冰对混凝土强度的损伤... 以盐溶液外部浸泡模拟混凝土表面防冰,以内部掺加盐分模拟混凝土内部防冰。通过抗压与弯拉试验分析了2种氯盐施加方式对混凝土强度的影响;又通过室内冻结试验分析了氯盐施加方式对防冰效率的影响。结果表明:内部防冰对混凝土强度的损伤程度要大于外部防冰;两种方式在初始冻结时间上几乎无明显差异,在完全冻结时间上内部防冰的延迟效果显著弱于表面防冰。由此可判断,强度损伤主要来源于内部,防冰效率则来源于表层。因此,防冰涂层与防渗层组合具有应用前景。 展开更多
关键词 氯盐 水泥混凝土 防冰
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纳米Y_2O_3∶Eu^(3+)中S_6格位电荷迁移带的光学特性 被引量:3
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作者 贾明理 张家骅 +5 位作者 吕少哲 孙江亭 骆永石 任新光 宋宏伟 王笑军 《发光学报》 EI CAS CSCD 北大核心 2004年第1期62-66,共5页
在Y2 O3 ∶Eu3 + 体材料和纳米材料中 ,观察到紫外激发下处于S6格位的Eu3 + 的5D0 →7F1发射 ( 5 82nm)的强度 ,相对处于C2 格位的5D0 →7F0 发射 ( 5 80nm)的强度 ,随着激发波长在 2 0 0~ 3 0 0nm紫外区由长变短而增强。这一现象说明Y... 在Y2 O3 ∶Eu3 + 体材料和纳米材料中 ,观察到紫外激发下处于S6格位的Eu3 + 的5D0 →7F1发射 ( 5 82nm)的强度 ,相对处于C2 格位的5D0 →7F0 发射 ( 5 80nm)的强度 ,随着激发波长在 2 0 0~ 3 0 0nm紫外区由长变短而增强。这一现象说明Y2 O3 ∶Eu3 + 中两种格位的电荷迁移带及基质激发的性质不同。光谱分解得出S6格位的电荷迁移带位于C2 格位电荷迁移带的高能侧 ,Y2 O3 基质倾向于向S6格位进行能量传递。与体材料相比 ,两种格位的电荷迁移带在纳米材料中都发生红移 ;相对于C2 格位的电荷迁移带 ,S6格位的电荷迁移带强度在纳米材料中比在体材料中明显降低 ,并对结果进行了讨论。 展开更多
关键词 铕离子掺杂 纳米三氧化二钇 电荷迁移带 格位 能量传递 纳米技术
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4个不同素因子Nicol数的几个结论
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作者 蔡宇泽 王伟 《沙洲职业工学院学报》 2014年第1期38-41,共4页
研究了具有4个不同素因子Nicol数,得到了3-Nicol数可能存在的四种形式;并且证明了4-Nicol数只可能为n=2^(α1)3^(α2)5^(α3)p^(α4),P≥7为素数。
关键词 Nicol数 整除 互素 欧拉函数
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皮秒BBO-OPG/OPA系统对极微弱光信号放大的实验研究 被引量:1
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作者 杜仕峰 张东香 +3 位作者 施玉显 王素梅 冯宝华 张景园 《量子电子学报》 CAS CSCD 北大核心 2007年第1期126-126,共1页
利用OPG/OPA获得宽调谐、高能量、高相干的辐射光源,在军事技术、空间科学以及环境保护的遥感遥测中已显示出越来越广泛的应用前景。然而,传统遥感遥测一般采用对信号进行直接探测,其灵敏度有限,因此对高灵敏度和高适用性遥感遥测... 利用OPG/OPA获得宽调谐、高能量、高相干的辐射光源,在军事技术、空间科学以及环境保护的遥感遥测中已显示出越来越广泛的应用前景。然而,传统遥感遥测一般采用对信号进行直接探测,其灵敏度有限,因此对高灵敏度和高适用性遥感遥测技术的研究是值得期待的。本文采用皮秒BBO-OPG/OPA系统对极微弱光信号进行放大研究,得到3.28×10^8的增益。从而为来自遥远目标的微弱光信号的探测找到了更好的方法。 展开更多
关键词 光信号放大 PA系统 皮秒 实验 遥测技术 直接探测 高灵敏度 辐射光源
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基于上转换荧光粉的紫外光源设计 被引量:1
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作者 陈凤 陈璐 +5 位作者 刘峰 张亮亮 武华君 吴昊 王笑军 张家骅 《发光学报》 EI CAS CSCD 北大核心 2021年第2期131-135,共5页
提到荧光粉光转化(Phosphor-converted,PC)类型的光源,人们熟悉的是白光照明或近红外波段的光源,而对紫外波段PC光源的概念比较陌生。本文基于蓝光激发的上转换发光现象,提出了一个新型PC紫外光源的概念。首先选取Lu_(2)Pr_(0.01)Gd_(0.... 提到荧光粉光转化(Phosphor-converted,PC)类型的光源,人们熟悉的是白光照明或近红外波段的光源,而对紫外波段PC光源的概念比较陌生。本文基于蓝光激发的上转换发光现象,提出了一个新型PC紫外光源的概念。首先选取Lu_(2)Pr_(0.01)Gd_(0.99)Al_(2)Ga_(3)O_(12)上转换荧光粉为展示材料,该材料在450 nm激光辐照下发射位于313 nm的紫外线。随后,采用刮涂工艺将该荧光粉材料制备成荧光陶瓷薄膜。通过蓝光远程激发荧光粉层的方法对荧光薄膜的紫外发射进行了成像演示。目前来看,尽管这个PC设计的光转换效率并不高,但光谱和成像实验显示了其作为紫外光源的可行性。该设计可以为明亮环境下的紫外示踪或指示等应用提供选择。 展开更多
关键词 荧光粉光转化 PC紫外光源 Pr^(3+)离子上转换 Gd^(3+)发射 荧光陶瓷薄膜
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上转换充能的动力学研究——以Mn^(2+)掺杂的长余辉材料为例 被引量:2
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作者 李辰琳 赵习宇 +4 位作者 郭彤 刘峰 王笑军 廖川 张家骅 《物理学报》 SCIE EI CAS CSCD 北大核心 2022年第7期316-322,共7页
无机长余辉材料是一种储能释光材料,其储能特性源于材料内部的电子或空穴陷阱在外界激发光作用下的填充..通过上转换激发的方式对长余辉材料充能是学者们在近几年提出的一种新颖的激发充能机制.这种两步离化的激发设计使长余辉材料的充... 无机长余辉材料是一种储能释光材料,其储能特性源于材料内部的电子或空穴陷阱在外界激发光作用下的填充..通过上转换激发的方式对长余辉材料充能是学者们在近几年提出的一种新颖的激发充能机制.这种两步离化的激发设计使长余辉材料的充能摆脱了高能离化光的限制,将充能激发波长扩展至可见光甚至红外光区,为长余辉技术在生物成像等领域的应用提供了原位激发的选择.目前,学者们对上转换充能的研究主要集中在材料的开发和激发路径的设计等方面,而对充能本身的物理过程知之甚少.本文通过构建分析上转换充能的速率方程,预测了激发辐照光对陷阱的光排空影响.在此基础上,选择450 nm激光激发的LaMgGa_(11)O_(19):Mn^(2+)长余辉材料体系为模板,分析了激发光剂量与材料热释光强度的函数关系,揭示了光辐照陷阱填充与光排空之间的动力学竞争.此外,相似的充能动力学规律也适用于其他具有上转换充能性质的长余辉材料. 展开更多
关键词 长余辉材料 上转换充能 陷阱填充动力学 LaMgGa_(11)O_(19):Mn^(2+)
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蓝光LED激发深紫外上转换发光材料的光学定位与追踪应用 被引量:3
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作者 梁延杰 刘景伟 +2 位作者 闫劭 陈东讯 王笑军 《发光学报》 EI CAS CSCD 北大核心 2022年第9期1436-1445,共10页
光发射波长小于320 nm的深紫外发光材料具有光子能量高和不受室内环境光干扰等特性,在光化学与光医学领域具有重要应用前景,近年来受到国内外学者的广泛关注。本文利用固相合成法制备了Pr^(3+)单掺和Pr^(3+)⁃Gd^(3+)共掺的LiYSiO_(4)∶P... 光发射波长小于320 nm的深紫外发光材料具有光子能量高和不受室内环境光干扰等特性,在光化学与光医学领域具有重要应用前景,近年来受到国内外学者的广泛关注。本文利用固相合成法制备了Pr^(3+)单掺和Pr^(3+)⁃Gd^(3+)共掺的LiYSiO_(4)∶Pr^(3+)和Li(Y,Gd)SiO_(4)∶Pr^(3+)深紫外上转换发光材料。在450 nm蓝光(激光或LED)激发下分别实现了C区紫外和窄带B区紫外上转换发光,发光峰值分别位于280 nm和313 nm。系统研究了蓝光激发功率对深紫外上转换发光性能的影响规律,证实了蓝光激发下的双光子上转换发光物理机制。探索利用LiYSiO_(4)∶Pr^(3+)作为光转换层,以蓝光LED作为激发源,设计构筑了新型荧光转换型UVC光源,并展示了该光源在室外光学定位与追踪领域的应用。 展开更多
关键词 紫外上转换发光 紫外光源 Pr^(3+) Pr^(3+)-Gd^(3+) 光学定位与追踪
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红外波段的长余辉发光 被引量:2
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作者 刘峰 杨峰 +5 位作者 杨慧 苑佳琪 翁维易 于雅淳 刘娅琳 王笑军 《发光学报》 EI CAS CSCD 北大核心 2018年第11期1487-1495,共9页
红外长余辉技术在生物成像探测及夜视保密探测等领域有着广阔的应用前景。本文结合该领域近期的一些进展,对红外长余辉的定义、发光离子的选择、发光动力学过程以及红外长余辉激发谱学技术等几方面进行了简要阐述。在阐述过程中也着重... 红外长余辉技术在生物成像探测及夜视保密探测等领域有着广阔的应用前景。本文结合该领域近期的一些进展,对红外长余辉的定义、发光离子的选择、发光动力学过程以及红外长余辉激发谱学技术等几方面进行了简要阐述。在阐述过程中也着重指出了红外长余辉领域今后的几个可能学术研究方向。 展开更多
关键词 红外长余辉 Cr^3+激活余辉 Yb^3+激活余辉 光激励余辉 上转换余辉
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多重智力理论及其对学校教育的价值 被引量:2
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作者 冯建华 罗晓路 《心理发展与教育》 CSSCI 北大核心 1997年第1期34-39,共6页
多重智力理论是由美国心理学教授加德纳提出的关于智力性质和结构的新理论,这个理论认为个体具有多种彼此相互联系又相对独立的智力,它由语言、数理/逻辑、视觉/空间、身体/运动、音乐/节奏、人际交往和自我认识等七种智力成分组成,这... 多重智力理论是由美国心理学教授加德纳提出的关于智力性质和结构的新理论,这个理论认为个体具有多种彼此相互联系又相对独立的智力,它由语言、数理/逻辑、视觉/空间、身体/运动、音乐/节奏、人际交往和自我认识等七种智力成分组成,这些基本智力间的不同组合,反映了个体间的智力差异。这个理论目前还有诸多争论,但因此掀起了一场教育思想的新革命,对我国学校教育中的智力观、教学观、考试观和学生观都有所启迪,为教育者充分认识和发挥学生的潜能提供了新的理论依据。 展开更多
关键词 智力 智力多重理论 学校教育
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Bromate ion formation in dark chlorination and ultraviolet/chlorination processes for bromide-containing water 被引量:11
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作者 HUANG Xin GAO Naiyun DENG Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第2期246-251,共6页
Bormate (BrO3^-) is a carcinogenic chemical produced in ozonation or chlorination of bromide-containing water. Although its formation in seawater with or without sunlight has been previously investigated, the format... Bormate (BrO3^-) is a carcinogenic chemical produced in ozonation or chlorination of bromide-containing water. Although its formation in seawater with or without sunlight has been previously investigated, the formation of bromate in dilute solutions, particularly raw water for water treatment plant, is unknown. In this article, the results of bench scale tests to measure the formation rates of bromate formation in dilute solutions, including de-ionized water and raw water from Yangtze River, were presented in dark chlorination and ultraviolet (UV)/chlorination processes. And the effects of initial pH, initial concentration of NaOCl, and UV light intensity on bromate formation in UV/chlorination of the diluted solutions were investigated. Detectable bromate was formed in dark chlorination of the two water samples with a relatively slow production rate. Under routine disinfecting conditions, the amount of formed bromate is not likely to exceed the national standards (10 μg/L). UV irradiation enhanced the decay of free chlorine, and, simultaneously, 6.6%-32% of Br^- was oxidized to BrO3^-. And the formation of bromate exhibited three stages: rapid stage, slow stage and plateau. Under the experimental conditions (pH = 4.41-11.07, CCl2= 1.23-4.50 mg/L), low pH and high chlorine concentration favored the generation of bromate. High light intensity promoted the production rate of bromate, but decreased its total generation amount due to acceleration of chlorine decomposition. 展开更多
关键词 BROMATE CHLORINATION raw water Yangtze River ultraviolet (UV) irradiation
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The contribution of small and large sensory afferents to postural control in patients with peripheral neuropathy 被引量:6
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作者 Li Li Shuqi Zhang John Dobson 《Journal of Sport and Health Science》 SCIE 2019年第3期218-227,共10页
Peripheral neuropathy(PN) is a multifarious disorder that is caused by damage to the peripheral nerves. Although the symptoms of PN vary with the etiology, most cases are characterized by impaired tactile and proprioc... Peripheral neuropathy(PN) is a multifarious disorder that is caused by damage to the peripheral nerves. Although the symptoms of PN vary with the etiology, most cases are characterized by impaired tactile and proprioceptive sensation that progresses in a distal to proximal manner. Balance also tends to deteriorate as the disorder becomes more severe, and those afflicted are substantially more likely to fall while walking compared with those who are healthy. Most patients with PN walk more cautiously and with greater stride variability than age-matched controls, but the majority of their falls occur when they must react to a perturbation such as a slippery or uneven surface. The purpose of this study was to first describe the role of somatosensory feedback in the control of posture and then discuss how that relationship is typically affected by the most common types of PN. A comprehensive review of the scientific literature was conducted using MEDLINE, and the relevant information was synthesized. The evidence indicates that the proprioceptive feedback that is conveyed primarily through larger type I afferents is important for postural control. However, the evidence indicates that the tactile feedback communicated through smaller type II afferents is particularly critical to the maintenance of balance. Many forms of PN often lead to chronic tactile desensitization in the soles of the feet and, although the central nervous system seems to adapt to this smaller type II afferent dysfunction by relying on more larger type I afferent reflex loops, the result is still decreased stability. We propose a model that is intended both to help explain the relationship between stability and the smaller type II afferent and the larger type I afferent feedback that may be impaired by PN and to assist in the development of pertinent rehabilitative interventions. 展开更多
关键词 BALANCE BIOMECHANICS NEUROPLASTICITY PERIPHERAL NEUROPATHY POSTURAL control Rehabilitation
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基质中非4f组态的电子态对Pr^(3+)离子发光的影响(英文) 被引量:6
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作者 刘峰 王笑军 《发光学报》 EI CAS CSCD 北大核心 2017年第1期1-6,共6页
三价镨离子(Pr^(3+))是一种备受关注的稀土发光离子。学者们在过去几十年里对其发光性质进行了大量的理论和实验研究。在不同的基质材料中,由于非4f组态的电子态与Pr^(3+)离子发光能级相互作用,Pr^(3+)离子可以展现从紫外到红外波段的... 三价镨离子(Pr^(3+))是一种备受关注的稀土发光离子。学者们在过去几十年里对其发光性质进行了大量的理论和实验研究。在不同的基质材料中,由于非4f组态的电子态与Pr^(3+)离子发光能级相互作用,Pr^(3+)离子可以展现从紫外到红外波段的不同特征的光发射。影响Pr^(3+)离子发光的这些电子态可能源于4f5d激发组态、电荷迁移态或类激子态。本文中,我们以几种具有代表性的发光材料为例,简短地总结和评述了Pr^(3+)离子发光的不同谱形;也尝试解释了几个新颖的实验现象,例如:杂质束缚激子态和电荷迁移态对发光的猝灭影响。我们希望这些相关概念和谱学结果的整理有助于读者更好地理解一些实验上的发光现象,并为设计发光材料提供新的思路。 展开更多
关键词 Pr3+ 1S0发射 1D2发射 杂质束缚激子态 电荷迁移态 红外发光
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K_(3)La(PO_(4))_(2)基质中Tb^(3+)的发光和能量传递 被引量:5
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作者 欧奕意 王笑军 梁宏斌 《发光学报》 EI CAS CSCD 北大核心 2022年第9期1350-1360,I0001,共12页
采用高温固相方法合成了不同浓度Tb^(3+)掺杂的单斜结构K_(3)La(PO_(4))_(2)荧光粉,利用XRD表征了其相纯度,并对基质化合物进行了结构精修。研究了Tb^(3+)掺杂样品在不同温度下的发光性质及不同掺杂浓度样品在室温下的发光性质。发现在... 采用高温固相方法合成了不同浓度Tb^(3+)掺杂的单斜结构K_(3)La(PO_(4))_(2)荧光粉,利用XRD表征了其相纯度,并对基质化合物进行了结构精修。研究了Tb^(3+)掺杂样品在不同温度下的发光性质及不同掺杂浓度样品在室温下的发光性质。发现在室温、373 nm激发下,Tb^(3+)离子表现为^(5)D_(3)⁃7F_(J)(J=5,4,3,2)和^(5)D_(4)⁃^(7)F_(J)'(J'=6,5,4,3)等两组发射。不同温度下低掺样品的光谱测试表明,多声子弛豫对5D_(3)能级发射的猝灭贡献有限。随着掺杂浓度增加,Tb^(3+)离子5D_(3)发射减弱而5D_(4)发射增强,样品表现出从青光到绿光的光色调控性质,这主要是由Tb^(3+)能级间的交叉弛豫过程导致的;进一步通过Inokuti⁃Hirayama模型和扩展的Yokota⁃Tanimoto模型对5D_(3)发光衰减曲线进行拟合,结果表明能量传递的主要作用方式为电偶极⁃四极作用,临界传递距离约为1.03 nm。 展开更多
关键词 Tb^(3+) K_(3)La(PO_(4))_(2) 发光 能量传递 多声子弛豫 交叉弛豫
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