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Frontiers of Mechanical Engineering 2023年第4期18卷 183-193页

作者： Alexander SCHMIDT felix JENSCH Sebastian HÄRTEL Chair of Hybrid Manufacturing Brandenburg University of TechnologyCottbus 03046Germany

Many processes may be used for manufacturing functionally graded *** them,additive manufacturing seems to be predestined due to near-net shape manufacturing of complex geometries combined with the possibility of applying different materials in one *** adjusting the powder composition of the starting material layer by layer,a macroscopic and step-like gradient can be *** further improve the step-like gradient,an enhancement of the in-situ mixing degree,which is limited according to the state of the art,is *** this paper,a novel technique for an enhancement of the in-situ material mixing degree in the melt pool by applying laser remelting(LR)is *** effect of layer-wise LR on the formation of the interface was investigated using pure copper and low-alloy steel in a laser powder bed fusion *** cross-sectional selective electron microscopic analyses were carried *** applying LR,the mixing degree was enhanced,and the reaction zone thickness between the materials was ***,an additional copper and iron-based phase was formed in the interface,resulting in a smoother gradient of the chemical composition than the case without *** Marangoni convection flow and thermal diffusion are the driving forces for the observed effect.

关键词： multi-material additive manufacturing(MMAM) functionally graded materials(FGMs) laser powder bed fusion(L-PBF) laser remelting(LR) pure copper

Influence of Yttrium Ion-Implantation on the Growth Kinetics and Micro-Structure of NiO Oxide Film

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Plasma Science and Technology 2008年第1期10卷 43-45页

作者：靳惠明 Adriana felix Majorri AROYAVE College of Mechanical Engineering Yangzhou University Yangzhou 225009 China College of Materials Engineering National University of Antiuquia Medellin 23715 Colombia

Isothermal and cyclic oxidation behaviours of pure and yttrium-implanted nickel were studied at 1000℃ in air. Scanning electronic microscopy （SEM） and transmission electronic microscopy （TEM） were used to examine the micro-morphology and structure of oxide scales formed on the nickel substrate. It was found that Y-implantation significantly improved the anti- oxidation ability of nickel in both isothermal and cyclic oxidizing experiments. Laser Raman microscopy was also used to study the stress status of oxide scales formed on nickel with and without yttrium. The main reason for the improvement in anti-oxidation of nickel was that Y- implantation greatly reduced the growing speed and grain size of NiO. This fine-grained NiO oxide film might have better high temperature plasticity and could relieve parts of compressive stress by means of creeping, and maintained a ridge character and a relatively low internal stress level. Hence yttrium ion-implantation remarkably enhanced the adhesion of protective NiO oxide scale formed on the nickel substrate.

关键词： ion-implantation laser Raman stress oxide yttrium

Imaging in translational cancer research

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Cancer Biology & Medicine 2022年第11期19卷 1565-1585页

作者： felix T.Kurz Heinz-Peter Schlemmer Department of Radiology German Cancer Research CenterHeidelberg 69120Germany

This review is aimed at presenting some of the recent developments in translational cancer imaging research,with a focus on novel,recently established,or soon to be established cross-sectional imaging techniques for computed tomography(CT),magnetic resonance imaging(MRI),and positron-emission tomography(PET)imaging,including computational investigations based on machine-learning techniques.

关键词： Cancer imaging computed tomography(CT) magnetic resonance imaging(MRI) positron emission tomography(PET) cross-sectional imaging

Biaxial versus uniaxial strain tuning of single-layer MoS_(2)

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Nano Materials Science 2022年第1期4卷 44-51页

作者： felix Carrascoso Riccardo Frisenda Andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de Madrid(ICMM-CSIC)28049Madrid Spain

Strain engineering has arisen as a powerful technique to tune the electronic and optical properties of twod imensional semiconductors like molybdenum disulfide(MoS_(2)).Although several theoretical works predicted that biaxial strain would be more effective than uniaxial strain to tune the band structure of MoS_(2),a direct experimental verification is still missing in the *** we implemented a simple experimental setup that allows to apply biaxial strain through the bending of a cruciform polymer *** used the setup to study the effect of biaxial strain on the differential reflectance spectra of 12 single-layer MoS_(2)flakes finding a redshift of the excitonic features at a rate between-40 meV/%and-110 meV/%of biaxial *** also directly compare the effect of biaxi al and uniaxial strain on the same single-layer MoS_(2)finding that the biaxial strain gauge factor is 2.3 times larger than the uniaxial strain one.

关键词： finding layer gauge

Towards an Internet-like Power Grid

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 1-11页

作者： Iasonas Kouveliotis-Lysikatos Nikos Hatziargyriou Yanli Liu felix Wu Department of Electrical Engineering and Computer Science KTH-Royal Institute of TechnologyTeknikringen 3310040StockholmSweden School of Electrical and Computer Engineering National Technical University of Athens15773 AthensGreece School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina Department of Electrical Engineering and Computer Sciences University of CaliforniaBerkeleyCA 94720USA

The great challenges faced by modern power systems require a fresh look at the conventional operation paradigm. The significant challenges faced by modern power systems require an innovative method for the conventional operation paradigm. We claim that the decarbonization of the power grid and extensive electrification of numerous sectors of human activity can only be fostered by a self-adaptable and smart power grid that manifests similar qualities to those of the Internet. The Internet is constructed on a layered architecture that facilitates technology innovations and its intelligence is distributed throughout a hierarchy of networks. In this paper, the fundamental differences between the network data flows and power flows are examined, and the basic requirements for an innovative operation paradigm are highlighted. The current power grid is operated in a highly inflexible, centralized manner to meet increased security goals. A new highly flexible, distributed architecture can be realized by distributing the operation responsibility in smaller areas or even in grid components that can make autonomous decisions. The characteristics of such a power grid are presented, and the key features and advances for the on-going transition to a sustainable power system are identified. Finally, a case study on distributed voltage control is presented and discussed.

关键词： Smart grid Internet distributed intelligence decentralized architecture

Analysis of pneumatic atomizer spray profiles

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Particuology 2016年第6期14卷 80-85页

作者： Walter Schafer Simon Rosenkranz felix Brinckmann Cameron Tropea AOM-Systems GmbH Flughafenstrasse 15 64347 Griesheim Germany LacTec GmbH Otto-Hahn-Strasse 6-8 63110 Rodgau Germany Institute of Fluid Mechanics and Aerodynamics Technische Universitat Darmstadt Alarich-Weiss-Strasse 10 64287 Darmstadt Germany Graduate School of Computational Engineering Technische Universitat Darmstadt Dolivostrasse 15 64287 Darmstadt Germany

Our objective is to analyze the atomization processes of a pneumatic atomizer by measuring the size and velocity distributions of droplets in a liquid paint spray. The droplet size and velocity distributions have been determined at different axial positions in the spray; a mathematical description of how these quan- tities vary throughout the spray is then proposed. Additionally, the relative number density of droplets and the relative local mass flux are estimated.

关键词： Pneumatic atomizer Spray Measurement Droplet size profile Droplet velocity profile Time-shift

CHLORAD: Eradicating Translocon Components from the Outer Membrane of the Chloroplast

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Molecular Plant 2019年第4期12卷 467-469页

作者： Venkatasalam Shanmugabalaji felix Kessler Laboratory of Plant Physiology University of Neuchatel 2000 Neuchatel Switzerland

Around 100 proteins are produced inside the chloroplast but the vast majority must be imported. These proteins are synthesized in the cytosol as preproteins with cleavable targeting sequences. Several plastid types other than chloroplasts exist. During plant development, one plastid type may be converted to another, a process referred to as plastid transition (Jarvis and Lopez-Juez, 2013). During plastid transitions, proteome remodeling occurs, and one set of imported proteins is replaced by another that is functionally adapted (Kleffmann et al., 2007). Moreover, plastid proteomes are known to be regulated in an environmentdependent fashion, and chloroplasts may respond to changing light conditions by regulating the composition and abundance of photosynthetic complexes.

关键词： CHLORAD Eradicating Translocon Components Outer Membrane Chloroplast

Strain engineering in single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2)and WSe_(2)

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Nano Research 2021年第6期14卷 1698-1703页

作者： felix Carrascoso Hao Li Riccardo Frisenda Andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de MadridConsejo Superior de Investigaciones Cientificas28049MadridSpain

Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS_(2),MoSe_(2),WS_(2) and WSe_(2).In this work we provide a thorough description of the technical details to perform uniaxial strain measurements on these two-dimensional semiconductors and we provide a straightforward calibration method to determine the amount of applied strain with high *** then employ reflectance spectroscopy to analyze the strain tunability of the electronic properties of single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2) and WSe_(2).Finally,we quantify the flake-to-flake variability by analyzing 15 different single-layer MoS_(2) flakes.

关键词： two-dimensional(2D)materials transition metal dichalcogenides strain engineering band gap differential reflectance

Assessing the influence of harvesting intensities on structural diversity of forests in south-west Germany

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Forest Ecosystems 2019年第3期6卷 249-260页

作者： felix Storch Gerald Kadler Jürgen Bauhus Chair of Silviculture University of FreiburgD-79085 FreiburgGermany Department of Biometry Forest Research Institute of Baden-WürttembergD-79100 FreiburgGermany

Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management for many forest owners and jurisdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed Forest Structure Index and HI is expressed as wood volume removal during the period 2002-2012 for the same inventory plots. Results: Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80%-90% of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantially negatively influenced at HI > 60% and 70% of initial growing stock, respectively. Conclusions: In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adjust levels of HI that are suited to maintain forest biodiversity.

关键词： Large-scale inventory Structural diversity index Harvesting intensity Changes in structural diversity

Security of the Internet Transactions

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计算机科学 2002年第Z1期29卷 83-84,72页

作者： felix Musau College of Information Science & Engineering Central South University Changsha410083

The new generation of networked business solutions brings legacy data and applications to the world wide Web, and lets companies redefine internal and external business processes. The present need for internet transaction has forced many business to adopt the internet forms of distribution of its business items. This has threatened security, hence needs to be given a key priority. This paper alights the key areas on how to protect the information we transact on the internet. It also aims at improving the security of our data and the computers we use to access this data.

关键词： Authentication Cryptography Web secure Transaction server COM