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| 1 | 基于修正的Havriliak-Negami模型的SiO_2纳米改性变压器油宽频介电弛豫特性显示文摘为了掌握纳米改性变压器油介电性能,探索纳米改性内在机理,对Si O2纳米改性变压器油介质损耗特性进行了试验研究。首先在室温条件下分别对纯变压器油和Si O2纳米改性变压器油的宽频介电谱进行测试,然后引入修正的Havriliak-Negami模型方程对实测结果进行拟合,并从该模型中提取了相应的介电参数用于分析纳米油介电性能的变化规律。试验结果表明,与纯变压器油介电谱相比,Si O2纳米油介电谱的低频段电导损耗降低了,而中高频段极化损耗增加了。经分析与讨论,可认为Si O2纳米颗粒添加到变压器油中,纳米颗粒与油分子形成微观双电层结构,其增加了纳米流体中载流子跃迁势垒,致使纳米油宏观介电性能发生一定程度改变。 | 温福新 董明 任明 Christof Sumereder Michael Muhr | 2016 | 电工技术学报2016，31，7： | 10 |
| 2 | Particle-size-dependent upconversion luminescence of NaYF4:Yb,Er nanoparticles in organic solvents and water at different excitation power densities显示文摘A systematic study of the luminescence properties of monodisperse β-NaYF4: 20%Yb^3+,2%Er^3+ upconversion nanoparticles (UCNPs)with sizes ranging from 12--43nm is presented utilizing steady-state and time-resolved fluorometry. Special emphasis was dedicated to the absolute quantification of size-and environment-induced quenching of upconversion luminescence (UCL)by highenergy O-H and C-H vibrations from solvent and ligand molecules at different excitation power densities (P).In this context,the still-debated population pathways of the 4F9/2 energy level of Er^3+ were examined.Our results highlight the potential of particle size and P value for color tuning based on the pronounced near-infrared emission of 12nm UCNPs,which outweighs the red Er^3+emission under 'strongly quenched'conditions and accounts for over 50% of total UCL in water.Because current rate equation models do not include such emissions,the suitability of these models for accurately simulating all (de)population pathways of small UCNPs must be critically assessed.Furthermore,we postulate population pathways for the 4F9/2energy level of Er3.,Which correlate with the size-,environment-,and P-dependent quenching states of the higher Er^3+ energy levels. | Marco Kraft Christian Würth Verena Muhr Thomas Hirsch Ute Resch-Genger | 2018 | Nano Research2018，11，12： | 8 |
| 3 | Usage and Benefit of an Overhead Line Monitoring System显示文摘Overhead lines are the backbone of the electrical power transmission.Contrary to the distributions networks,the transmission system consists only in exceptional cases of longer cable lines.Typical exceptions are connections of cavern power plants,approaches to airports or bird sanctuaries and lines in urban centres.In the majority of cases,an overhead line is the most economic and practicable solution for the energy transmission.In tourism regions,an overhead line will be seen as impairment of nature or landscape and so the approval chain and procedure is in most countries long-winded and circumstantial.At the other hand,the energy consumption in Europe is growing and the volatility of transmitted power is also increasing during the last decade caused by the opening of the electric energy market.This opening process leads to a stopping of the enlargement of the interoperation network and to a minimisation of the maintenance of existing lines.Today the network operates more often at the limit of the equipment and the small and large-areas disturbances and blackouts are increasing.The operators of transmission lines are forced to ensure the electrical power supply and so they have to improve the reliability of the network.One solution is to monitor the critical(heavy loaded)overhead lines.For example,with the knowledge of the thermal condition,the risk of unexpected outages can be reduced.Today several monitoring systems are available on the market.They differ in the principle and techniques of the condition evaluation.The three most interesting output variables are the line temperature,the capable transmission power and the actual sag of the investigated section.In this paper an overview of existing overhead line monitoring system and also an outline over the usage and benefit for the application will be given.Thermal monitoring is one technique to improve the reliability of the network and for increasing or optimising the capable transmission power. | M. Muhr S. Pack S. Jaufer | 2008 | 高电压技术2008，34，12： | 4 |
| 4 | 直流电压下纳米改性变压器油流场测试与分析显示文摘纳米改性变压器油在导热性和介电强度上较普通变压器油均有显著提高,具有广泛的应用前景。针对纳米改性变压器油强化传热机理,采用粒子图像测试技术(particle image velocimetry,PIV)测试了纳米改性变压器油在直流电场下的流场分布,并与普通变压器油流场进行了对比分析。试品放在有机玻璃杯内,电极为相距1cm的两圆形平面电极以产生均匀电场,示踪粒子为直径为10μm的中空玻璃球;流场测试平面为电极的中心面,分别施加10,15,20k V的直流高压。结果表明:纳米改性变压油在电场下的流场比普通变压器油流场更有规律性,流速场由正极板到负极板逐渐减慢,比普通变压器油在电场下平均流速更快,说明纳米颗粒的添加使得整个变压油的流动性质发生了变化,使得变压器油的散热效果更好,这也是纳米改性变压器油导热性增强的原因之一,并间接证明了双电层结构假设的正确性。 | 戴建卓 董明 王丽 王健一 林梅 Michael Muhr | 2016 | 中国电机工程学报2016，36，15： | 3 |
| 5 | 温度对纳米改性变压器油宽频介电谱特性的影响显示文摘纳米改性变压器油在绝缘性能和传热性能的优势已经得到了国内外学者的广泛认可,但现阶段大多数学者的研究多集中于纳米改性变压器油的宏观特性上,且对于其改性机理尚不明确,通过研究纳米油微观结构与电导、极化之间的相关性,可以为探索纳米油的改性机理以及推广实际应用提供一定的理论参考。该文主要研究了温度对纳米改性变压器油频域介电谱的影响,在10–2~106Hz频率范围内对纳米油介电谱特性进行了分析讨论。随着温度的增加,纳米油的直流电导率呈指数型增加;而在介电谱的中高频段,出现了一个明显的极化峰,随着温度的增加,极化峰峰值逐渐减小且向高频方向移动,Schwarz双电层极化理论可用来解释这一现象。 | 温福新 董明 任明 戴建卓 SUMEREDER Christof MUHR Michael | 2016 | 中国电机工程学报2016，36，8： | 3 |
| 6 | Multiband emission from single β-NaYF_(4)(Yb,Er) nanoparticles at high excitation power densities and comparison to ensemble studies显示文摘Ensemble and single particle studies of the excitation power density (P)-dependent upconversion luminescence (UCL) of core and core-shell β-NaYF_(4):Yb,Er upconversion nanoparticles (UCNPs) doped with 20% Yb^(3+) and 1% or 3% Er^(^(3+)) performed over a P regime of 6 orders of magnitude reveal an increasing contribution of the emission from high energy Er^(3+) levels at P > 1 kW/cm^(2). This changes the overall emission color from initially green over yellow to white. While initially the green and with increasing P the red emission dominate in ensemble measurements at P < 1 kW/cm^(2), the increasing population of higher Er^(^(3+)) energy levels by multiphotonic processes at higher P in single particle studies results in a multitude of emission bands in the ultraviolet/visible/near infrared (UV/vis/NIR) accompanied by a decreased contribution of the red luminescence. Based upon a thorough analysis of the P-dependence of UCL, the emission bands activated at high P were grouped and assigned to 2–3, 3–4, and 4 photonic processes involving energy transfer (ET), excited-state absorption (ESA), cross-relaxation (CR), back energy transfer (BET), and non-radiative relaxation processes (nRP). This underlines the P-tunability of UCNP brightness and color and highlights the potential of P-dependent measurements for mechanistic studies required to manifest the population pathways of the different Er^(3+) levels. | Florian Frenzel Christian Würth Oleksii Dukhno Frédéric Przybilla Lisa MWiesholler Verena Muhr Thomas Hirsch Yves Mély Ute Resch-Genger | 2021 | Nano Research2021，14，11： | 3 |
| 7 | Epidemiology of traumatic spine fractures显示文摘 | Philipp Leucht Klaus Fischer Gert Muhr Ernst J. Mueller | 2008 | Injury2008，，2： | 2 |
| 8 | 纳米添加量对纳米改性变压器油宽频介电弛豫特性的影响显示文摘为了探索纳米改性变压器油的微观结构与宏观性能的相关性,选择绝缘体二氧化硅为改性材料,在室温条件下,制备出了不同体积分数的二氧化硅纳米改性变压器油并对其稳定性进行了测试。通过对油样进行介电谱曲线复介电常数的测量,对比分析了纯油和纳米改性变压器油的介电谱曲线以及不同体积分数二氧化硅对纳米油介电谱曲线的影响。研究结果表明:和未添加纳米颗粒的变压器油相比,纳米油在介电谱复介电常数虚部曲线的低频段和高频段均出现一个较为明显的极化峰,且低频极化峰峰值要高于高频极化峰,而在整个测试频率范围内,纯油未出现明显的极化峰;体积分数升高,纳米油的介电谱虚部值在低频段和高频段的极化峰均有所增加,且低频极化峰有向高频方向移动的趋势。Schwarz的双电层极化理论被用来解释这一现象。 | 董明 李阳 戴建卓 任明 Christof Sumereder Michael Muhr | 2017 | 高电压技术2017，43，9： | 2 |
| 9 | Rubber abrasion and wear 显示文摘 | Muhr A H Robert A D | 1992 | Wear1992，158，： | 1 |
| 10 | Burst fracture of the fifth lumbar vertebra:results of posterior internal fixation and transpedicular bone grafting 显示文摘 | Kamminski A Mullr EJ Muhr G | 2002 | 11:435-4402002，11，： | 1 |
| 11 | Traumatic spondylolisthesis of the axis:treatment rationale based on the stability of the different fracture types显示文摘 | Muller EJ Wick M Muhr G | | 0，，2： | 1 |
| 12 | Removal of Boron from Wastewater by Precipitation of a Sparingly Soluble Salt 显示文摘 | P Remy H Muhr E Plasari | 2005 | Environmental Progress2005，24，1： | 1 |
| 13 | Rubber abrasion and wear显示文摘 | Muhr A H Robert A D | 1992 | Wear1992，158，： | 1 |
| 14 | Primary human keratinocytes efficiently induce IL-1-dependent IL-17 in CCR6+ T cells显示文摘 | Muhr P Renne J Schaefer V | 2010 | Exp Dermatol2010，19，12： | 1 |
| 15 | Atlas/ti - a prototype for the support of text interpretation 显示文摘 | Muhr T | 1991 | Qual Soc1991，14，： | 1 |
| 16 | Modification of vimentin:a general mechanism of nonenzymatic glycation in human skin显示文摘 | Kueper T Grune T Muhr GM | | 0，，： | 1 |
| 17 | Low-intensity pulsed ultrasound as a useful adjuvant during distraction osteogenesis: a prospective, randomized controlled trial显示文摘 | Dudda M Hauser J Muhr G | 2011 | J Trauma2011，71，5： | 1 |
| 18 | The beneficial effects of early stabi- lization of thoracic spine fractures depend on trauma severity 显示文摘 | Frangen TM Ruppert S Muhr G | 2010 | J Trauma2010，11，5： | 1 |
| 19 | 显示文摘 | Krumeich F Schonholzer U P | 2000 | Adv Mater2000，12，3： | 1 |
| 20 | Diffenrent levels of repressor activity assign redundant and specific roles to Nkx6 genes in motor neuron and interneuron specification 显示文摘 | Vallstedt A Muhr J Pattyn A | 2001 | Neuron2001，31，： | 1 |
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