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用于气体频谱分析传感器的245 GHz次谐波接收机

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微电子学 2019年第6期49卷 783-787页

作者：毛燕飞鄂世举 Klaus Schmalz j.christoph scheytt 浙江师范大学工学院浙江金华321000 东南大学毫米波国家重点实验室南京211189 IHP Microelectronics Frankfurt(Oder)15236Germany Heinz Nixdorf Institute Paderborn UniversityPaderborn 33102Germany

提出了一种用于气体频谱分析传感器的混频器优先的245 GHz次谐波接收机。该接收机具有高线性度、高带宽、低噪声系数、低功耗和高集成度的特点。该接收机由2次无源反接并联二极管对(APDP)次谐波混频器、120 GHz推推型压控振荡器-分频器... 详细信息

提出了一种用于气体频谱分析传感器的混频器优先的245 GHz次谐波接收机。该接收机具有高线性度、高带宽、低噪声系数、低功耗和高集成度的特点。该接收机由2次无源反接并联二极管对(APDP)次谐波混频器、120 GHz推推型压控振荡器-分频器链路和120 GHz功率放大器构成。采用特征频率/最大振荡频率为300 GHz/500 GHz的SiGe BiCMOS工艺进行实现。结果表明,该接收机芯片的转换增益为-16 dB,带宽为14 GHz,单边带噪声系数为19 dB,输入1 dB压缩点为0 dBm,功耗为213 mW。

关键词：混频器优先次谐波接收机 BiCMOS工艺

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一种低功耗245 GHz次谐波接收机

红外与毫米波学报 2019年第6期38卷 739-744页

作者：毛燕飞鄂世举 SCHMALZ Klaus scheytt j.christoph 浙江师范大学工学院浙江金华321000 东南大学毫米波国家重点实验室江苏南京211189 IHP MicroelectronicsFrankfurt Oder15236Germany Heinz Nixdorf Institute Paderborn University33102Germany

介绍了一种应用于气体频谱分析传感器的低功耗245 GHz次谐波接收机,该接收机具有低功耗、高线性度和高集成度的特点.该接收机由四级共基极低噪声放大器、二次次谐波无源反接并联二极管对(APDP)混频器、120GHz推推型压控振荡器-分频器链... 详细信息

介绍了一种应用于气体频谱分析传感器的低功耗245 GHz次谐波接收机,该接收机具有低功耗、高线性度和高集成度的特点.该接收机由四级共基极低噪声放大器、二次次谐波无源反接并联二极管对(APDP)混频器、120GHz推推型压控振荡器-分频器链路、120 GHz功率放大器和中频放大器构成,采用了特征频率为300 GHz、最大振荡频率为500 GHz的锗硅BiCMOS工艺实现.该接收机芯片实现了10.6 dB的转换增益和13 GHz的带宽,噪声系数为20 dB,输入1dB压缩点仿真结果为-9 dBm,接收机如果不包括120 GHz压控振荡器-功率放大器链路功耗为99.6 mW,接收机包括120 GHz压控振荡器-功率放大器链路功耗为312 mW.

关键词： 245 GHz 次谐波接收机锗硅BiCMOS工艺低功耗共基极低噪声放大器二次次谐波无源反接并联二极管对混频器中频放大器

Branched side chains improve molecular packing of non-fullerene acceptors

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Science China Chemistry 2021年第9期64卷 1435-1436页

作者： Ning Li christoph j.Brabec Institute of Materials for Electronics and Energy Technology(i-MEET) Friedrich-Alexander University Erlangen-NürnbergMartensstraße 7Erlangen91058Germany Helmholtz-Institute Erlangen-Nürnberg(HI ERN) Immerwahrstraße 2Erlangen91058Germany

As one of the promising emerging photovoltaic technologies(PVs),organic solar cells(OSCs)have received extensive attention from both scientific and industry *** advantages of OSCs,such as low toxicity,high power-toweight ratio,and easy manufacturing and upscaling,guarantee their contribution to versatile applications powered by clean and renewable solar energy,for instance.

关键词： chains packing versatile

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Three-dimensional CityGML building models in mobile augmented reality: a smartphone-based pose tracking system

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International journal of Digital Earth 2021年第1期14卷 32-51页

作者： christoph Blut jörg Blankenbach Geodetic Institute Department of Computing in Civil Engineering and Geo-Information SystemsRWTH Aachen UniversityAachenGermany

Many augmented reality(AR)systems are developed for entertainment,but AR and particularly mobile AR potentially have more application possibilities in other *** example,in civil engineering or city planning,AR could be used in combination with CityGML building models to enhance some typical workflows in planning,execution and operation processes.A concrete example is the geo-referenced on-site visualization of planned buildings or building parts,to simplify planning processes and optimize the communication between the participating *** of the main challenges for the visualization lies in the pose tracking,*** real-time estimation of the translation and rotation of the mobile device to align the virtual objects with *** this paper,we introduce a proof-of-concept fine-grained mobile AR CityGML-based pose tracking system aimed at the mentioned *** system estimates poses by combining 3D CityGML data with information derived from 2D camera images and an inertial measurement unit and is fully self-sufficient and operates without external *** results of our evaluation show that CityGML and low-cost off-the-shelf mobile devices,such as smartphones,already provide performant and accurate mobile pose tracking for AR in civil engineering and city planning.

关键词： Mobile augmented reality pose tracking CityGML 3D city model Android smartphone

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245 GHz接收机芯片片外测试与实验

太赫兹科学与电子信息学报 2020年第3期18卷 358-363页

作者：毛燕飞鄂世举 SCHMALZ Klaus scheytt j.christoph 颜素莉浙江师范大学工学院浙江金华321000 东南大学毫米波国家重点实验室江苏南京211189 IHP MicroelectronicsFrankfurt Oder15236Germany Heinz Nixdorf Institute Paderborn University33102Germany

为了实现太赫兹气体频谱分析传感器,对245 GHz次谐波接收机芯片的片外测试展开研究。建立了245 GHz次谐波接收机片外测试系统以及基于245 GHz接收机芯片及发射机芯片的气体频谱分析传感器片外展示测试系统,对245 GHz次谐波接收机芯片转... 详细信息

为了实现太赫兹气体频谱分析传感器,对245 GHz次谐波接收机芯片的片外测试展开研究。建立了245 GHz次谐波接收机片外测试系统以及基于245 GHz接收机芯片及发射机芯片的气体频谱分析传感器片外展示测试系统,对245 GHz次谐波接收机芯片转换增益和带宽进行测试。片外测试系统得到15 dB转换增益和15 GHz带宽;片外展示测试系统得到9 dB转换增益和16 GHz带宽。片外测试系统和片外展示测试系统结果基本吻合。在片外展示测试系统中加入气腔,即构成气体频谱分析传感器。与现有同类型传感器相比,本文的次谐波接收机具有高增益、高带宽、集成本地振荡信号、低功耗等优势,非常适用于消费电子领域小体积的智能气体频谱分析传感器。

关键词： 245 GHz次谐波接收机片外测试系统片外展示测试系统气体频谱分析传感器系统高增益高带宽低功耗

Stand dynamics of the drought-affected floodplain forests of Araguaia River,Brazilian Amazon

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Forest Ecosystems 2017年第3期4卷 201-210页

作者： jürgen Homeier Dariusz Kurzatkowski christoph Leuschner Plant Ecology Albrecht von Haller Institute for Plant Sciences University of Goettingen

Background： The floodplain forests of Araguaia River, a clear-water river in the southeastern Amazon（Tocantins State, Brazil）, are characterized by seasonal flooding up to 3.5 m height, low nutrient levels in the water, and seasonal drought periods of 4–5 ***： We studied the forest dynamics（tree diameter growth, tree mortality and recruitment） of this unique forest ecosystem over a 5-year period by repeated censuses in 12 permanent plots established along a flooding ***： The cumulative basal area in the plots increased by 0.84（±0.45） m^2·ha^-1·yr^-1（mean ±SD） in the annual y-flooded（AF） plots in lower terrain and by 0.69（±1.00） m^2·ha^-1·yr^-1 in the higher non-annual y flooded（NAF） plots, corresponding to an aboveground biomass increase of 0.81（±0.57） and 0.69（±1.58） Mg·ha^-1·yr^-1 in the AF and NAF plots, indicating a recent carbon sink in the biomass. Mean diameter growth rate was 1.8（±0.44） mm·yr^-1 in the AF and 2.0（±0.56） mm·yr^-1 in the NAF plots（corresponding to a coarse wood production of 1.53（±1.29） and 2.02（±0.52） Mg·ha^-1·yr^-1）,indicating no flooding effect on radial growth. Mean mortality rates in the 5-year period were 1.9（±0.37）·yr^-1 in the AF plots and 1.8（±0.87）%·yr^-1 in the NAF plots with no differences along the flooding gradient. Highest mortalities were registered in the AF plots for the 10–20 cm dbh class（2.4%·yr^-1）, likely as a consequence of flooding,and in the NAF plots for the 40–50 cm dbh class（3.0%·yr^-1）, probably mainly caused by ENSO-related ***： We conclude that these drought-affected tropical floodplain forests have a lower standing biomass and aboveground productivity than central Amazonian floodplain forests in more humid climates, and the imprint of the flooding gradient on stand dynamics is relatively weak, which may result from the lower flooding height and the interaction of flooding with low nutrient supply and periodic drought.

关键词： Amazon Diameter growth Dry season Flooding regime Mortality rate Productivity Tree recruitment

CityGML goes mobile: application of large 3D CityGML models on smartphones

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International journal of Digital Earth 2019年第1期12卷 25-42页

作者： christoph Blut Timothy Blut jörg Blankenbach Department of Computing in Civil Engineering and Geo Information Systems Geodetic InstituteRWTH Aachen UniversityAachenGermany

CityGML,a semantic information model for digital/virtual city models has become quite popular in various *** the data format is still actively under development,it is already supported by different software solutions,especially GIS-based desktop *** systems on the other hand are still neglected,even though the georeferenced objects of CityGML have many application fields,for example,in the currently popular area of location-based Augmented *** this paper we present an independent multi-platform CityGML viewer,its architecture and specific implementation techniques that we use to realize and optimize the process of visualizing CityGML data for use in Augmented *** main focus lies in improving the implementation on mobile devices,such as smartphones,and assessing its usability and performance in comparison to web-based *** to the constrained hardware resources of smartphones,it is a particular challenge to handle complex 3D objects and large virtual worlds as provided by CityGML,not only in terms of memory and storage space,but also with respect to mobile processing units and display sizes.

关键词： CityGML city model android 3D visualization real-time rendering

Asymptomatic pancreatic lesions: New insights and clinical implications

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World journal of Gastroenterology 2012年第33期18卷 4474-4477页

作者： Martin Loos christoph W Michalski jrg Kleeff Department of Surgery Klinikum rechts der Isar Technische Universitt München 81675 München Germany

Despite great efforts in experimental and clinical research, the prognosis of pancreatic cancer (PC) has not changed significantly for decades. Detection of pre-invasive lesions or early-stage PC with small resectable cancers in asymptomatic individuals remains one of the most promising approaches to substantially improve the overall outcome of PC. Therefore, screening programs have been proposed to identify curable lesions especially in individuals with a familial or genetic predisposition for PC. In this regard, Canto et al recently contributed an important article comparing computed tomography, magnetic resonance imaging, and endoscopic ultrasound for the screening of 216 asymptomatic high-risk individuals (HRI). Pancreatic lesions were detected in 92 of 216 asymptomatic HRI (42.6%). The high diagnostic yield in this study raises several questions that need to be answered of which two will be discussed in detail in this commentary: First: which imaging test should be performed? Second and most importantly: what are we doing with incidentally detected pancreatic lesions? Which ones can be observed and which ones need to be resected?

关键词： Pancreatic cancer Early-stage pancreatic cancer Asymptomatic high-risk individuals Preinvasive pancreatic lesions Cystic pancreatic tumors Screening Computed tomography Magnetic resonance imaging Endoscopic ultrasound

Magnetic labeling of primary murine monocytes using very small superparamagnetic iron oxide nanoparticles

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Neural Regeneration Research 2022年第10期17卷 2311-2315页

作者： Martin Pohland christoph Pohland jürgen Kiwit jana Glumm Institute of Cell Biology and Neurobiology Center for AnatomyCharité-Universitätsmedizin BerlinBerlinGermany Department of Neurosurgery Helios Klinikum Berlin BuchBerlinGermany

Due to their very small size,nanoparticles can interact with all cells in the central nervous *** of the most promising nanoparticle subgroups are very small superparamagnetic iron oxide nanoparticles(VSOP)that are citrate coated for electrostatic *** determine their influence on murine blood-derived monocytes,which easily enter the injured central nervous system,we applied VSOP and carboxydextran-coated superparamagnetic iron oxide nanoparticles(Resovist).We assessed their impact on the viability,cytokine,and chemokine secretion,as well as iron uptake of murine blood-derived *** found that(1)the monocytes accumulated VSOP and Resovist,(2)this uptake seemed to be nanoparticle-and time-dependent,(3)the decrease of monocytes viability was treatment-related,(4)VSOP and Resovist incubation did not alter cytokine homeostasis,and(5)overall a 6-hour treatment with 0.75 mM VSOP-R1 was probably sufficient to effectively label monocytes for future *** homeostasis is not altered,it is safe to label blood-derived monocles with *** labeled monocytes can be used to study injured central nervous system sites further,for example with drug-carrying VSOP.

关键词： CD11b,cytokine Ferucarbotran Mac1 MPS MRI Resovist superparamagnetic iron oxide nanoparticles(SPIO) very small superparamagnetic iron oxide nanoparticles(VSOP) viability