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Research in Astronomy and Astrophysics 2018年第1期18卷 1-10页

作者： Gui-Yun Liang Hui-Gang Wei Da-Wei Yuan Fei-Lu Wang Ji-Min Peng Jia-Yong Zhong Xiao-Long Zhu mike schmidt Günter Zschornack Xin-Wen Ma Gang Zhao Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Department of Astronomy Beijing Normal University Beijing 100875 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China DREEBIT GmbH 01109 Dresden Germany

Spectra are fundamental observation data used for astronomical research,but understanding them strongly depends on theoretical models with many fundamental parameters from theoretical *** models give different insights for understanding a specific ***,laboratory benchmarks for these theoretical models become *** electron beam ion trap is an ideal facility for spectroscopic benchmarks due to its similar conditions of electron density and temperature compared to astrophysical plasmas in stellar coronae,supernova remnants and so *** this paper,we will describe the performance of a small electron beam ion trap/source facility installed at National Astronomical Observatories,Chinese Academy of *** present some preliminary experimental results on X-ray emission,ion production,the ionization process of trapped ions as well as the effects of charge exchange on the ionization.

关键词： X-ray:general atomic processes line:formation method:laboratory:atomic

Targeting Epac2 and GluA3-containing AMPARs:a novel therapeutic strategy for Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3223-3224页

作者： Tong Zhang Martina schmidt Department of Molecular Pharmacology Groningen Research Institute of PharmacyUniversity of GroningenGroningenThe Netherlands School of Pharmacy Tianjin Medical UniversityTianjinChina

Alzheimer's disease(AD)is a neurodegenerative disease that manifests progressive decline in memory and *** the early stage of AD,memory retrieval is impaired preceding memory acquisition and consolidation(Roy et al.,2016).Prior to the onset of symptoms,pathological amyloid-β(Aβ)plagues and tau protein tangles accumulate in extracellular and intracellular spaces,respectively,leading to *** these hallmark pathologies,Aβ is proposed to be the primary etiology by triggering a cascade of pathogenic events,including neuroinflammation,oxidative stress,tau hyperphosphorylation,synaptic/neuronal dysfunction,and neuronal death(Zhang et al.,2023b).

关键词： Alzheimer impaired Aβ

Modelling of particle layer detachment—Role of transient kinetic effects

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Particuology 2009年第1期7卷 45-51页

作者： Eberhard schmidt Faculty D-Safety Engineering/Environmental Protection University of WuppertalBuilding FFRainer-Gruenter-StrasseD-42119 WuppertalGermany

Particle layers tend to build up on wails in many filtration and separation processes, calling for periodic removal in order to keep the apparatus running. Important factors are the adhesion of the layer on the substrate and the cohesion of the particles in the layer. Models describing such layer detachment generally assume constant and homogeneous conditions for the forces acting on the layer. But in reality detachment is extremely non-stationary concerning place and time, primarily due to changing conditions of the detaching forces on the one hand and changes in the particle layer morphology on the other. This paper describes a model and a simulation based on this model considering such transient kinetic effects, for which some computing results are presented and discussed.

关键词： Adhesive forces Filter cleanability Dust cake discharge Patchy cleaning

Quantification of particle separation using electrostatically charged spray mist in a dust chamber

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Particuology 2021年第5期19卷 92-98页

作者： Marcel Zillgitt Eberhard schmidt Institute of Particle Technology Rainer Gruenter StraBeBuilding FFCampusFreudenbergBergische Universitat Wuppertal42119 WuppertalGermany

In order to improve the efficiency of reducing fine dust emissions from diffuse sources,the commonly used water mist can be electrostatically ***,the attraction between particles and droplets increases due to electrostatic field *** the experimental investigations carried out,an electrostatic two-fluid nozzle was used to generate a charged spray mist according to the principle of charging by *** a chamber,dispersed dust was precipitated with the spray mist,while detecting the laser light *** means of comparative measurements it could be shown that faster sedimentation and separation takes place through electrostatic *** variations regarding the use of compressed air and water were investigated and the sedimentation time of the particle-droplet mixture in the chamber was shown.A size distribution was then calculated from the laser light attenuation,which shows that the proportion of small particles decreases with spray ***,the influence of the polarity of droplets and solid particles on the reduction measure was determined.

关键词： Dust separation Spray mist Electrostatic Dust chamber Laser light attenuation Charging by induction

Navigation sensors and systems in GNSS degraded and denied environments

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维普期刊数据库

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Chinese Journal of Aeronautics 2015年第1期28卷 1-10页

作者： George T.schmidt IEEE Aerospace and Electronic Systems Society

Position, velocity, and timing（PVT） signals from the Global Positioning System（GPS）are used throughout the world but the availability and reliability of these signals in all environments has become a subject of concern for both civilian and military applications. This presentation summarizes recent advances in navigation sensor technology, including GPS, inertial, and other navigation aids that address these concerns. Also addressed are developments in sensor integration technology with several examples described, including the Bluefin-21 system mechanization.

关键词： navigation inertial GNSS environments receiver degraded military addressed presentation advances

Machine learning guided high-throughput search of non-oxide garnets

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npj Computational Materials 2023年第1期9卷 1717-1725页

作者： Jonathan schmidt Hai-Chen Wang Georg schmidt Miguel A.L.Marques Institut für Physik Martin-Luther-Universität Halle-WittenbergD-06099 HalleGermany

Garnets have found important applications in modern technologies including magnetorestriction,spintronics,lithium batteries,*** overwhelming majority of experimentally known garnets are oxides,while explorations(experimental or theoretical)for the rest of the chemical space have been limited in scope.A key issue is that the garnet structure has a large primitive unit cell,requiring a substantial amount of computational *** perform a comprehensive search of the complete chemical space for new garnets,we combine recent progress in graph neural networks with high-throughput *** apply the machine learning model to identify the potentially(meta-)stable garnet systems before performing systematic density-functional calculations to validate the *** discover more than 600 ternary garnets with distances to the convex hull below 100 meV⋅atom−*** includes sulfide,nitride,and halide *** analyze their electronic structure and discuss the connection between the value of the electronic band gap and charge balance.

关键词： structure sulfide oxides

Application of dynamic image analysis to the optical characterisation of fibrous bulk material

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维普期刊数据库

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Particuology 2024年第7期90卷 51-60页

作者： Johannes Lunewski Eberhard schmidt Institute of Particle Technology University of WuppertalGermany

Dynamic image analysis provides an automated evaluation method to determine the size and shape of multiple particles. This method represents a common application for ordinary bulk material. The latest draft of ISO 13322–2:2021 describes the state of the art, but lacks instructions for handling fibrous bulk material. Interlocking fibres complicate the measurement conditions and require a disentanglement of fibrous samples during a pre-dispersion step. A further error source includes the fibre orientation inside the measurement zone of the device. If the thresholding algorithm fails to differentiate between the fibre projection area and the background, a subsequent image optimisation solves the problem. This article addresses the mentioned problems by analysing cotton cellulose and polyacrylonitrile fibres. Besides the execution of a pre-dispersion step, the experiments compare the discrepancies between dry and wet dispersion. Here, the software packages PAQXOS and ImageJ perform the image evaluation. In this case, the wet dispersion setup with a subsequent image evaluation by ImageJ provides comprehensible results.

关键词： Bootstrap method Dynamic image analysis Fibre diameter Fibre length distribution Natural fibres Synthetic fibres

Entangled-photons generation with quantum dots

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维普期刊数据库

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Chinese Physics B 2018年第2期27卷 140-153页

作者：李远丁飞 Oliver G schmidt Institute for Integrative Nanosciences IFW Dresden HelmholtzstraBe 20. 01069 Dresden. Germany Integrative for Solid State Physics. Leibniz University of Hunnover. AppelstBe 2.30 167 Hannovel Germany

Entanglement between particles is a crucial resource in quantum information processing, an important example of which is the exploitation of entangled photons in quantum communication protocols. Among the different available sources of entangled photons, semiconductor quantum dots （QDs） excel owing to their deterministic emission properties, potential for electrical injections, and direct compatibility with semiconductor manufacturing techniques. Despite the great promises, QD-based sources at＇e far from being ideal. In particular, such sources present several critical issues, which require the overcoming of challenges pertaining to spectral tunability, entanglement fidelity, photon indistinguishability and brightness. In this article, we will discuss the potential solutions to these problems and review the recent progress in the field.

关键词： quantum information entangled-photon source quantum dots

Incorporating shape constraints in generalized additive modelling of the height-diameter relationship for Norway spruce

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Forest Ecosystems 2016年第2期3卷 112-125页

作者： Natalya Pya Matthias schmidt Department of Mathematics School of Science and TechnologyNazarbayev University The Northwest German Forest Research Station Department of Forest Growth

Background： Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height （dbh） can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter （h-d） models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods： We develop unconstrained generalized additive models （GAM） and shape constrained generalized additive models （SCAM） for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results： Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions： We

关键词： Height-diameter curve Norway spruce Shape constrained additive models Impact of climate change,Varying coefficient models

Hepatic organ protection:From basic science to clinical practice

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World Journal of Gastroenterology 2010年第48期16卷 6044-6045页

作者： Rene schmidt Department of Anesthesiology and Critical Care Medicine Freiburg University Medical Center

Hepatic ischemia and reperfusion (I/R) injury during liver surgery is still the main cause of postoperative liver failure and the subsequent rise of mortality in these patients. During the last few years, a multitude of underlying mechanisms have been extensively characterized and many different protective approaches have been evaluated under experimental conditions. Some of them have already found their way into small sized clinical trials. In this Topic Highlight series of articles, we present recent insights into promising protective concepts including the regulation and optimization of hepatic blood flow, molecular mechanisms of preconditioning and pharmacological approaches with the aim of limiting hepatic I/R injury. Leading international experts present the latest experimental evidence in their fields stressing clinically relevant ideas, which are now on the edge of entering clinical practice.

关键词： Heme oxygenase-1 Hepatectomy Hepatic organ protection Ischemia/reperfusion injury Liver blood flow Liver transplantation Preconditioning