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Journal of Materials Science & Technology 2022年第7期102卷 89-96页

作者： Xu Liu Lin Song Andreas Stark uwe lorenz Zhanbing He Junpin Lin Florian Pyczak Tiebang Zhang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Institute of Materials Research Helmholtz-Zentrum GeesthachtMax Planck-Str.1Geesthacht 21502Germany State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

In modernβ-solidified TiAl alloys,the decomposition of α_(2) phase is frequently observed during heat treatment or high-temperature deformation of the *** this study,high-temperature deformation and decomposition mechanisms of α_(2) phase in a Ti-45Al-8.5Nb-0.2B-0.2W-0.02Y alloy are *** a sample deformed at 800℃,the precipitation ofβ_(o)(ω_(o))phase is observed within the equiaxed α_(2) *** nucleation ofω_(o) particles within theβ_(o) matrix indicates the α_(2)→β_(o)→ω_(o) *** addition,numerous y phase precipitates form within theβ_(o)(ω)*** α_(2) lamellae decompose into ultrafine( α_(2)+γ)lamellae and coarsened y lamellae via α_(2)→ α_(2)+γand α_(2)→γtransformation,***,theω_(o) phase nucleates within the ultrafine lamellae via α_(2)→ω_(o) ***,in a sample deformed at 1000℃,the nucleation ofβ_(o) particles is sluggish,which is caused by the efficient release of the internal stress via dynamic recrystallization(DRX).These results indicate that complex phase transformations can be introduced by the decomposition of α_(2) phase in TiAl alloys with a high amount ofβ-stabilizing elements.

关键词： TiAl alloys Phase transformation Microstructure Electron microscopy

On the reversibility of the α_(2)/ω_(o) phase transformation in a high Nb containing TiAl alloy during high temperature deformation

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Journal of Materials Science & Technology 2021年第34期93卷 96-102页

作者： Lin Song Fritz Appel Andreas Stark uwe lorenz Junyang He Zhanbing He Junpin Lin Tiebang Zhang Florian Pyczak State Key Laboratory of Solidification Processing Northwestern Poly technical University.Xi'an 710072China Institute of Materials Research Helmholtz-Zentrum GeesthachtMax Planck-Str.1Geesthacht 21502Germany Department of Microstructure Physics and Alloys Design Max-Planck-lnsdtut fiir Eisenforschung GmbHDusseldorf 40237Germany State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

The transformations between the phasesα_(2)(Ti_(3)Al)andω_(o)were investigated in a lamellar multiphase titanium aluminide alloy based onγ(TiAl).The paper complements an earlier investigation performed on the same material in which the importance of deformation-induced twin structures for theα_(2)→ω_(o) transformation was *** present study shows that the reverse transformationω_(o)→α_(2) can also occur during high-temperature *** transformation is probably triggered by constraint stresses,which exist between the different constituents due to the crystalline *** combined operation of mechanical twinning of theα_(2) phase and the reversible transformation fully converts theα_(2) lamellae into a mixture ofα_(2) andω_(o).This conversion greatly reduces the mechanical anisotropy existing in formerα_(2) *** the technical use of the alloy,the stability of the converted structure with respect to further annealing was also *** reported processes occur at the nano-meter and sub nano-meter scale,thus,advanced characterization techniques were applied,such as high-resolution transmission electron microscopy(HRTEM)and atom probe tomography(APT).

关键词： TiAl alloys Phase transformation Electron microscopy Microstructure

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快速而可靠地固定

现代制造 2005年第4期 48-50页

作者： uwe lorenz

新型快速夹紧系统能高精度地固定,简单地安装,同时可以根据零件种类的不同安装在各种不同的机床工作台上。这样的灵活夹紧系统,可以可靠而合理地固定各种几何形状和各种尺寸的工件。

关键词：数控机床 CNC 数控加工数控系统快速夹紧系统

Deep learning-based prediction of 3-dimensional silver contact shapes enabling improved quality control in solar cell metallization

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Energy and AI 2024年第3期17卷 513-524页

作者： Marius Singler Akshay Patil Linda Ney Andreas lorenz Sebastian Tepner Florian Clement Fraunhofer Institute for Solar Energy Systems(ISE) Heidenhofstr.279110 FreiburgGermany EKRA Automatisierungstechnik GmbH Zeppelinstraße 1674357 BonnigheimGermany

The industrial metallization of Si solar cells predominantly relies on screen printing,with silver as the preferred electrode ***,the design of commercial screens often leads to suboptimal silver usage and increased electrical resistance due to print-related inhomogeneities like mesh marks,constrictions and ***-time monitoring of quality parameters during production has thus become increasingly *** inline optical quality control systems usually only include 2D visualizations of the printed layout,which limits their effectiveness in quality *** that allow 3D measurements are usually slow,expensive,and therefore not worth considering in most *** research focuses on the development of a model that can estimate the three-dimensional shape of printed contact fingers from a single 2D image without the need of additional hardware using deep ***,a workflow for the generation of training data,which involves the creation of image pairs from a 2D microscope and a 3D confocal laser scanning microscope(CLSM)to accurately represent solar cell fingers,is *** model training,the predicted height maps are compared with the ground truth height maps,and the robustness of the model with respect to a paste variation and screen parameter variation is *** results confirm the feasibility and reliability of deep learning-based 3D shape estimation,extending its applicability to new,previously unseen data from screen-printed contact *** a structural similarity index(SSIM)score of 0.76,a strong correlation between the estimated and ground truth height maps is *** summary,our deep learning-based approach for height map estimation offers an effective and reliable solution for fast inline detection and analysis of the cross-sectional area of the printed contact fingers.

关键词： Deep Learning Front-side metallization Image2Heigth Solar cell Screen-printing

Impacts of brood parasitism by shiny cowbird Molothrus bonariensis on the breeding success of a small host, the black-backed water tyrant Fluvicola albiventer

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Current Zoology 2024年第4期70卷 539-547页

作者： Lorena Vanesa Sovrano Evelina Jesica Leon Rodrigo Ezequiel lorenzón Pamela Fernanda Olguin Adolfo Héctor Beltzer Alejandro Raúl Giraudo Laboratorio de Biodiversidad y Conservacion de Tetrapodos Instituto Nacional de Limnologia(INALICONICET-UNL)Paraje El Pozo s/nSanta Fe(3000)Argentina Departamento de Biologia Universidad Autonoma de Entre RiosKm 10.5 RP 11Oro Verde(3100)Entre RiosArgentina Departamento de Biologia Universidad Nacional del LitoralFacultad de Humanidades y CienciasParaje Ei Pozo s/nSanta Fe(3000)Argentina

The shiny cowbird Molothrus bonariensis parasitizes many species with different life-history traits and has a detrimental effect on the survival of the progeny of the *** response,hosts have developed numerous antiparasitic ***,we examined the effects of brood parasitism by shiny cowbird on the clutch and brood sizes(83 nests)in a small host,the black-backed water tyrant Fluvicola *** also studied whether the death of parasite nestlings was related to the care of the foster parents and whether the host had any antiparasitic defense against the shiny *** results indicate that brood parasitism significantly decreased the host hatching and fledging *** majority of nest failures(57%)were caused by brood *** cowbird parasitism occurred in 52%of nests and the intensity of parasitism was 1.23±0.53 eggs per parasitized *** the total host eggs,54%were *** the incubation stage,20 nests(47%)were abandoned because of egg punctures by shiny cowbirds *** two parasitic fledglings were recorded,while the remaining nestlings either died from starvation(n=12)or predation(n=3).Foster parents abandoned parasitic nestlings between 5 and 10 days *** findings demonstrate that the shiny cowbird has very low rates of fledging success when parasitizing black-backed water ***,parasitism had a high reproductive cost in the black-backed water tyrant because a very low proportion(7%)of the parasitized nests(n=43)were successful.

关键词： brood parasitism host defenses nest desertion shiny cowbird small host.

Propofol sedation in routine endoscopy:A case series comparing target controlled infusion vs manually controlled bolus concept

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World Journal of Gastrointestinal Endoscopy 2024年第1期16卷 11-17页

作者： Riad Sarraj lorenz Theiler Nima Vakilzadeh Niklas Krupka Reiner Wiest Department of Visceral Surgery and Medicine Inselspital University HospitalBern 3010Switzerland Clinic for Anesthesia PerioperativeEmergency&Intensive Care MedicineKantonsspital AarauAarau 5001Switzerland Department of Nephrology and Hypertension University Hospital LausanneLausanne 1011Switzerland

BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPS)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedation regimen by avoiding under-or *** To assess safety and performance of propofol TCI sedation in comparison with nurse-administered *** Fouty-five patients undergoing endoscopy under TCI propofol sedation were prospectively included from November 2016 to May 2017 and compared to 87 patients retrospectively included that underwent endoscopy with *** were matched for age and endoscopic *** recorded time of sedation and endoscopy,dosage of medication and adverse *** There was a significant reduction in dose per time of propofol administered in the TCI group,compared to the NAPS group(8.2±2.7 mg/min vs 9.3±3.4 mg/min;P=0.046).The time needed to provide adequate sedation levels was slightly but significantly lower in the control group(5.3±2.7 min vs 7.7±3.3 min;P<0.001),nonetheless the total endoscopy time was similar in both *** differences between TCI and bolus-sedation was observed for mean total-dosage of propofol rate as well as adverse *** This study indicates that sedation using TCI for GI endoscopy reduces the dose of propofol necessary per minute of *** may translate into less adverse ***,further and randomized trials need to confirm this trend.

关键词： Sedation Endoscopy Propofol Target controlled infusion Non-anaesthesiologist propofol sedation Adverse event

Optical magnetic field enhancement using ultrafast azimuthally polarized laser beams and tailored metallic nanoantennas

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Photonics Research 2024年第5期12卷 1078-1092页

作者： RODRIGO MARTIN-HERNANDEZ lorenz GRUNEWALD LUIS SANCHEZ-TEJERINA LUIS PLAJA ENRIQUECONEJERO JARQUE CARLOS HERNANDEZ-GARCIA SEBASTIAN MAI Grupo de Investigacion en Aplicaciones del Laser y Fotonica Departamento de Fisica AplicadaUniversidad de SalamancaE-37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaE-37008 SalamancaSpain Institute of Theoretical Chemistry Faculty of ChemistryUniversity of Vienna1090 ViennaAustria Vienna Doctoral School in Chemistry(DoSChem) Faculty of ChemistryUniversity of Vienna1090 ViennaAustria Departamento de Electricidad y Electrónica Universidad de Valladolid47011 ValladolidSpain

*** *** thank Valentina Shumakova,Elizaveta Gangrskaia,Alessandra Bellissimo,Audrius Pugzlys,and Andrius Baltu?ka for fruitful discussions and computational support by the Vienna Scientific Cluster(VSC 4).The authors thankfully acknowledge the computer resources at MareNostrum and SCAYLE,and the technical support provided by Barcelona Supercomputing Center(RES-FI-2022-3-0041).R.M.-H.,L.S.-T.,L.P.,E.C.J.,and C.H.-*** funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Grant Agreement No.851201)and support from Ministerio de Ciencia e Innovación(PID2022-142340NB-I00,PID2019-106910GB-I00).This research was funded in whole or in part by the Austrian Science Fund(FWF)(10.55776/ZK91).For open access purposes,the author has applied a CC BY public copyright license to any author accepted manuscript version arising from this submission.

关键词： metallic polarized discussions

Support elements in conventional tunneling–Focus on long-term behavior

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Underground Space 2018年第4期3卷 277-287页

作者： Robert Galler Stefan lorenz Chair of Subsurface Engineering Department of Mineral Resources EngineeringMontanuniversita¨t LeobenP.O.Box 8700Erzherzog Johann Str.3LeobenAustria

Owing to increasing traffic and the need for constructing second tunnel tubes including corresponding cross-passages,where only one tube existed thus far,sampling of tunnel-lining materials with an age of 30–40 years has been made *** and in situ tests were carried out to evaluate the long-term effects of the tunnel *** paper presents the outcomes regarding the long-term behav-ior of support elements and membranes after performing strength tests on inner and outer lining concrete samples,flat jack tests,rock bolt tests,and tests on re-extracted sheet membranes,as well as ***,the interface connection mechanical behavior in a double-shell-lined tunnel was investigated with laboratory *** aim of this research was to determine the characteristics of sheet membranes and geotextiles in the case of reduced load-bearing capacity caused by degradation of the primary *** results provide information on the load-sharing effects of the interaction between the primary and secondary lining,depending on the waterproofing sheet membrane and geotextile *** on the results,conclusions for new design approaches for underground infrastructure construction can be formulated.

关键词： Tunnel lining Long-term behavior Concrete Sheet membrane Rock bolt Flat jack test In situ tests

Resolvent Estimates and Quantification of Nonlinear Stability

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Acta Mathematica Sinica,English Series 2000年第1期16卷 1-20页

作者： Heinz-Otto Kreiss Jens lorenz Department of Mathematics UCLALos AngelesCA 90095USA Department of Mathematics and Statistics UNMAlbuquerqueNM 87131USA

The aim of this paper is to clarify the role played by resolvent estimates for nonlinear *** will give examples showing that a large resolvent may lead to a small domain of nonlinear *** other examples the resolvent is large,but the domain of nonlinear stability is completely *** case prevails depends on the details of the problem. We will also show that the size of the resolvent depends in an essential way on the norms that are used.

关键词： Resolvent estimates Nonlinear stability Pseudospectrum Convection-dominated flow

Effect of processing parameters on in situ screen printing-assisted synthesis and electrical properties of Ti3SiC2-based structures

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Journal of Advanced Ceramics 2021年第1期10卷 129-138页

作者： Mylena lorenz Nahum TRAVITZKY Carlos R.RAMBO Department of Materials Science University of Erlangen-Nuremberg91058 ErlangenGermany Tomsk Polytechnic University 634050 TomskRussia Departm ent of Electrical and Electronic Engineering Federal University of Santa Catarina88040-900 FlorianopolisBrazil

This work reports on the development of pastes containing Ti,TiC,Si,and C elementary powders for in situ synthesis of Ti3SiC2 via screen *** paste compositions were manufactured using two powder mixtures(Ti/Si/C and Ti/TiC/Si/C)with different *** pastes were screen printed onto Al2O3 substrates and sintered at 1400℃in argon varying the dwell time from 1 to 5 *** printed pastes containing TiC and excess of Si exhibited the lowest surface roughness and after 5 h sintering comprised of Ti3SiC2 as the majority *** electrical conductivity of this sample was found to range from 4.63×10^(4)to 2.57×10^(5)S·m^(-1)in a temperature range of 25-400℃.

关键词： MAX phases Ti3SiC2 screen printing in situ synthesis electrical conductivity