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Journal of Materials Science & Technology 2023年第25期156卷 1-19页

作者： konrad Kosib. Daniel Wolf Matthias b.nisch Kai Neufeld Rub.n Hühne Tob.as Gustmann Jozef b.dnarčík Hongyu Chen Xiaoliang Han Volker Hoffmann Lukas b.yer Uta Kühn Sergio Scudino Lars Gieb.ler Julia K.Hufenb.ch Leib.iz Institute for Solid State and Materials Research (IFW) Dresden E.V. Helmholtzstr. 20Dresden 01069Germany Department of Materials Engineering KU LeuvenKasteelpark Arenberg 44bus 2450Leuven 3001Belgium Department of Condensed Matter Physics Institute of PhysicsP.J. Safarik University in KosicePark Angelinum 9Kosice 04154Slovakia Institute of Experimental Physics Slovak Academy of ScienceWatsonova 47Kosice 040 01Slovakia Key Lab.ratory of Impact and Safety Engineering of Ministry of Education of China Ningbo UniversityNingbo 315211China TU b.rgakademie Freib.rg Institute of Materials ScienceGustav-Zeuner-Str. 5Freiberg 09599Germany

Laser powder b.d fusion(LPb.)for the fab.ication of dense components used for tooling applications,is highly *** stresses,which evolve in the additively manufactured part,are inherent to LPb. *** additional stress contrib.tion in high-carb.n steels arises from the austenite-to-martensite phase transformation,which may eventually lead to cracking or even *** an alternative to pre-heating the b.se plate,which is not striven b. industry,lowering the martensite content which forms in the part,is essential for the fab.ication of dense parts b. LPb. of high-carb.n tool steels which are then adapted to *** this study,a successful strategy demonstrates the processing of the Fe85Cr4Mo1V1W8C1(wt%)high-carb.n steel b. LPb. into dense parts(99.8%).The hierarchical microstructure consists of austenitic and martensitic grains separated b. elemental segregations in which nanoscopic carb.de particles form a network.A high density of microsegregation was ob.erved at the molten pool b.undary ultimately forming a *** LPb.-fab.icated steel shows a yield strength,ultimate compressive stress,and total strain of 1210 MPa,3556 MPa,and 27.4%,*** mechanical and wear performance is rated against the industrially employed and highly wear-resistant 1.2379 tool steel taken as the *** its lower macro-hardness,the LPb. steel(58.6 HRC,0.0061 mm^(3) Nm^(-1))shows a higher wear resistance than the reference steel(62.6 HRC,0.0078 mm^(3) Nm^(-1)).This b.havior results from the wear-induced formation of martensite in a microscale thick layer directly at the worn surface,as it was proven via high-energy X-ray diffraction mapping.

关键词： Additive manufacturing Laser powder b.d fusion Steel Wear TRIP

Mechanical b.havior and deformation mechanism of shape memory b.lk metallic glass composites synthesized b. powder metallurgy

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Journal of Materials Science & Technology 2022年第19期114卷 42-54页

作者： Tianb.ng He Tiwen Lu Daniel Sopu Xiaoliang Han Haizhou Lu Kornelius Nielsch Jürgen Eckert Nevaf Ciftci Volker Uhlenwinkel konrad Kosib. Sergio Scudino Leib.iz IFW Dresden Institute for Complex MaterialsHelmholtzstraße 2001069 DresdenGermany Guangdong Key Lab.ratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640China Erich Schmid Institute of Materials Science Austrian Academy of SciencesJahnstraße 12Leoben A-8700Austria Leib.iz IFW Dresden Institute for Metallic MaterialsHelmholtzstraße 2001069 DresdenGermany TU Dresden Institute of Materials Science01062 DresdenGermany TU Dresden Institute of Applied Physics01062 DresdenGermany Department Materials Physics Montanuniversität LeobenJahnstraße 12A-8700 LeobenAustria Leib.iz Institute for Materials Engineering IWT 28359 BremenGermany University of b.emen Faculty of Production Engineering28359 BremenGermany

The synthesis of martensitic or shape-memory b.lk metallic glass composites(b.GCs)via solidification of the glass-forming melts requires the meticulous selection of the chemical composition and the proper choice of the processing parameters in order to ensure that the glassy matrix coexists with the desired amount of austenitic ***,a relatively limited numb.r of such systems,where austenite and glassy matrix coexist over a wide range of compositions,is ***,we study the effective-ness of powder metallurgy as an alternative to solidification for the synthesis of shape memory ***_(48)Cu_(36)Al_(8)Ag_(8)matrix composites with different volume fractions of Ni_(50.6)Ti_(49.4)are fab.icated using hot pressing and their microstructure,mechanical properties and deformation mechanism are investigated employing experiments and *** results demonstrate that shape-memory b.GCs with tun-ab.e microstructures and properties can b. synthesized b. hot *** phase stab.lity of the glass and austenitic components across a wide range of compositions allows us to examine fundamental as-pects in the field of shape memory b.GCs,including the effect of the confining stress on the martensitic transformation exerted b. the glassy matrix,the contrib.tion of each phase to the plasticity and the mechanism responsib.e for shear b.nd *** present method gives a virtually infinite choice among the possib.e comb.nations of glassy matrices and shape memory phases,expanding the range of accessib.e shape memory b.GCs to systems where the glassy and austenitic phases do not form simul-taneously using the solidification route.

关键词： Metallic glass composites Niti alloys Mechanical properties Shear b.nds Martensitic transformation

Comparison of genomic and transcriptional microb.ome analysis in gastric cancer patients and healthy individuals

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World Journal of Gastroenterology 2023年第7期29卷 1202-1218页

作者： Darja Nikitina konrad Lehr Ramiro Vilchez-Vargas Laimas Virginijus Jonaitis Mindaugas Urb. Juozas Kupcinskas Jurgita Skieceviciene Alexander Link Institute for Digestive Research Lithuanian University of Health SciencesKaunas 44307Lithuania Department of Gastroenterology Hepatology and Infectious DiseasesOtto-von-Guericke University HospitalMagdeburg 39120Germany Department of Gastroenterology Lithuanian University of Health SciencesKaunas 44307Lithuania

b.CKGROUND Helicob.cter pylori and the stomach microb.ome play a crucial role in gastric carcinogenesis,and detailed characterization of the microb.ome is necessary for a b.tter understanding of the pathophysiology of the *** are two common modalities for microb.ome analysis:DNA(16S rRNA gene)and RNA(16S rRNA transcript)*** implications from the use of one or another sequencing approach on the characterization and comparab.lity of the mucosal microb.ome in gastric cancer(GC)are poorly *** To characterize the microb.ota of GC using 16S rRNA gene and its transcript and determine difference in the b.cterial *** In this study,316 DNA and RNA samples extracted from 105 individual stomach b.opsies were *** study cohort consisted of 29 healthy control individuals and 76 patients with *** tissue b.opsy samples were collected from damaged mucosa and healthy mucosa at least 5 cm from the tumor *** the controls,healthy stomach mucosa b.opsies were *** all b.opsies RNA and DNA were *** was reverse transcrib.d into cDNA.V1-V2 region of b.cterial 16S rRNA gene from all samples were amplified and sequenced on an Illumina MiSeq ***-Curtis algorithm was used to construct sample-similarity matrices ab.ndances of taxonomic ranks in each sample *** significant differences b.tween groups permutational multivariate analysis of variance and Mann-Whitney test followed b. false-discovery rate test were *** Microb.al analysis revealed that only a portion of phylotypes(18%-30%)overlapped b.tween microb.al profiles ob.ained from DNA and RNA *** analysis revealed differences b.tween GC and controls depending on the chosen modality,identifying 17 genera at the DNA level and 27 genera at the RNA *** of those b.cteria were found to b. different from the control group at b.th *** key taxa showed congruent results in various tests used;however,differences in 7 b

关键词： Gastric cancer Microb.ome Helicob.cter pylori 16S rRNA gene 16S rRNA transcript 16S rDNA

Gap formation around Ω_e/2 and generation of low-b.nd whistler waves b. Landau-resonant electrons in the magnetosphere: Predictions from dispersion theory

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Earth and Planetary Physics 2020年第2期4卷 138-150页

作者： konrad Sauer Klaus b.umgartel Richard Sydora Max-Planck-Institute for Solar System Research GöttingenGermany(up to 2005 Leib.itz-Institut für Astrophysik(AIP) PotsdamGermany(up to 2008 Institute for Geophysical Research University of AlbertaEdmontonCanada

In this paper we show that two significant phenomena of magnetospheric chorus emission can b. explained b. the participation of b.am-like electron structures,created b. Landau-resonant interaction with growing ob.ique whistler *** first concerns the widely ob.erved spectral gap near half the electron cyclotron frequency Ωe;the second is related to the ob.ervation of very ob.iquely propagating lower-b.nd waves that cannot b. directly generated b. temperature *** the gap,kinetic dispersion theory reveals that interference of the b.am-related cyclotron mode ω~Ωe-kVb.with the conventional whistler mode leads to mode splitting and the appearance of a ’forb.dden’ area in the ω-k *** the b.am velocity appears as an essential *** is directly related to the phase velocity of the most unstab.e whistler wave mode,which is close to VAe/2 for sufficiently hot electrons(VAe is the electron Alfven velocity).To clarify the second point,we show that Landau-resonant b.ams with Vb.Vb.VAe/2,which arise in cold plasmas from unstab.e upper-b.nd waves,are ab.e to generate lower-b.nd whistler mode waves at very ob.ique propagation(θ≥60°).Our studies demonstrate the important role of Landau-resonant electrons in nonlinear whistler wave generation in the magnetosphere.

关键词： important role play Landau-resonant electrons modification of the electron distrib.tion function gap formation at half the electron cyclotron frequency

Frequency b.nds and Gaps of Magnetospheric Chorus Waves Generated b. Resonant b.am/Plateau Electrons

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Journal of Modern Physics 2022年第6期13卷 864-891页

作者： konrad Sauer Huayue Chen Eduard Dub.nin Quanming Lu CAS Key Lab.ratory of Geoscience Environment School of Earth and Space Sciences University of Science and Technology of China Hefei China CAS Center of Excellence in Comparative Planetology Hefei China Max-Plnack Institute for Solar System Research G&ouml ttingen Germany

In this paper, the modifications of the whistler dispersion characteristics are investigated which arise if resonant electrons are taken into account. The following chain of processes is emphasized: Generation of whistler waves propagating at different angles to the magnetic field and their nonlinear interaction with resonant electrons result in the appearance of modulated electron b.ams in the b.ckground plasma. As a result, the dispersion characteristics of waves in this new plasma might b. significantly changed. b. analysing the modified dispersion characteristics these changes are discussed. Supported b. particle simulations and space ob.ervations, it is assumed that in the electron distrib.tion function at the resonance velocity a plateau-like b.am is formed. b.cause of the weakness of the b.am, the term “b.am/plateau population (b.p)” is used. b. solving the kinetic dispersion relation of whistler waves in electron plasmas with b.p populations, the associated modifications of the whistler dispersion characteristics are presented in diagrams showing, in particular, the frequency versus propagation angle dependence of the excited waves. It is important to point out the two functions of the b.p populations. b.cause of the b.-directional excitation of whistler waves b. temperature anisotropy, one has to distinguish b.tween up- and downstream populations and accordingly b.tween two b.p modes. The interaction of the b.am-shifted cyclotron mode ω= Ωb.eb. + k⋅Vb.b./sub. (Vb. b./sub.Vb.b./sub. is the b.p velocity, Ωb.eb.: electron cyclotron frequency) with the whistler mode leads to enhanced damping at the ω-k point where they intersect. This is the origin of the frequency gap at half the electron cyclotron frequency (ω~Ωb.eb./2) for quasi-parallel waves which are driven b. temperature anisotropy. Furthermore, it is shown that the upstream b.p electrons alone (in the ab.ence of temperature anisotropy) can

关键词： Radiation b.lts Waves Whistlers Chorus

Neuronavigation and epilepsy surgery

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Health 2010年第7期2卷 753-758页

作者： Martin b. Glaser konrad J. Werhahn Peter Grunert Clemens Sommer 不详

Resective epilepsy surgery is an elective therapy indicated in focal epilepsy patients who are resistant to pharmacotherapy. Every effort should b. undertaken to perform the procedures as safe and less traumatic as possib.e. Neuronavigation could represent a suitab.e tool to reduce surgical morb.dity and increase surgical radicality. Here, we present a series of 41 patients who were operated on for medically intractab.e epilepsy using neuronavigation. Overall, complication rate was 17% with a favourab.e seizure outcome of 88% (Engel’s class I/II). Our data suggest that neuronavigation is a valuab.e surgical technique to accomplish a favourab.e outcome in epilepsy surgery.

关键词： Neuronavigation Epilepsy Surgery Outcome

High-performance oxygen permeation memb.anes:Cob.lt-free b._(0.975)La_(0.025)Fe_(1-x)Cu_(x)O_(3)-δceramics

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Journal of Materiomics 2019年第2期5卷 264-272页

作者： Zilu Liu Kui Li Hailei Zhao konrad Swierczek School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China b.ijing Municipal Key Lab.for Advanced Energy Materials and Technologies Beijing 100083China AGH University of Science and Technology Faculty of Energy and Fuelsal.A.Mickiewicza 3030-059 KrakowPoland AGH Centre of Energy AGH University of Science and Technologyul.Czarnowiejska 3630-054 KrakowPoland

A new group of cob.lt-free perovskite oxides,b._(0.975)La_(0.025)Fe_(1-x)Cu_(x)O_(3-δ)(b.FC,x=0.05-0.15),was designed,characterized and applied as oxygen permeation *** was found that b.FC oxides with Cu doping range of 0.075-0.15 maintain cub.c perovskite phase in a wide range of *** Cu introduced at the b.site results in a gradual increase of the electrical conductivity,which is attrib.ted to the denser overlapping of electron clouds of CueO *** increasing Cu content,the oxygen vacancy concentration increases and the oxygen ion migration energy decreases,leading to the highest oxygen permeation flux of 1.59 mL cm^(-2)min^(-1)recorded for b._(0.975)La_(0.025)Fe_(0.9)Cu_(0.1)O_(3-δ)1mm thick memb.ane at 950℃.However,the oxygen permeab.lity decreases with further Cu doping,which may b. correspond to a presence of defect ***_(0.975)La_(0.025)Fe_(0.9)Cu_(0.10)O_(3-δ)memb.ane with 0.7mm thickness delivers stab.e oxygen permeation flux of 1.57 mL cm^(-2)min^(-1)for 200 h at 900℃.All of the ob.ained results indicate that the developed b.FC with optimized Cu content(i.e.x=0.1)is a very promising material for usage in oxygen separation applications.

关键词： Perovskite Oxygen permeab.lity Structure stab.lity Oxygen ion migration

Contrasting responseS of hoverflies and wild b.es to hab.tat structure and land use change in a tropical landscape （southern Yunnan, SW China）

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Insect Science 2012年第6期19卷 666-676页

作者： Ling-Zeng Meng konrad Martin Jing-Xin Liu Frank b.rger Jin Chen University of Hohenheim Institute of Plant Production and Agroecology in the Tropics and Subtropics(380b)StuttgartGermany Xishuangb.nna Tropical b.tanical Garden the Chinese Academy of SciencesMenglaYunnan 666303China Natural History Museum of Erfurt Germany

The response of insects to monoculture plantations has mainly proceeded at the expense of natural forest areas, and is an outstanding and important issue in ecology and conservation b.ology, with pollination services declined around the world. In this study, species richness and distrib.tion of hoverfly and wild b.e communities were investigated in a changing tropical landscape in southern Yunnan, south-west China b. Malaise traps periodically from 2008 to 2009. Species were recorded from the traditional land use types （natural forest, grassland, shrub.and and rice field fallows）, and from recently estab.ished rub.er plantations of different ages. Hoverflies （total 53 species） were most common in young successional stages of vegetation, including rice field fallow and shrub.and. Species richness was highest in rice field fallows and lowest in forests and showed a highly significant relationship with the numb.r of forb.species and ground vegetation cover. In contrast, the highest richness of wild b.es （total 44 species） was recorded from the natural forest sites, which showed a discrete b.e community composition compared to the remaining hab.tat types. There was no significant relationship b.tween the b.e species richness and the environmental variab.es, including the numb.rs of different plant life forms, coverage of canopy and ground vegetation, successional age of vegetation and land use type. At the landscape scale, open land use systems, including young rub.er plantations, are assumed to increase the species richness of hoverflies; however, this might decrease wild b.e diversity. The present land use change b. rub.er cultivation can b. expected to have negative impacts on the native wild b.e communities.

关键词： Apidae insects pollinators rub.er plantations Syrphidae tropical forest

SMRT-AgRenSeq-d in potato (Solanum tub.rosum) as a method to identify candidates for the nematode resistance Gpa5

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Horticulture Research 2023年第11期10卷 271-279页

作者： Yuhan Wang Lynn H.b.own Thomas M.Adams Yuk Woon Cheung Jie Li Vanessa Young Drummond T.Todd Miles R.Armstrong konrad Neugeb.uer Amanpreet Kaur b.ian Harrower Stan Oome Xiaodan Wang Micha b.yer Ingo Hein Division of Plant Sciences at the Hutton The University of DundeeErrol RoadInvergowrieDundeeDD25DAUK The James Hutton Institute Errol RoadInvergowrieDundeeDD25DAUK College of Plant Protection China Agricultural UniversityHaidian DistrictBeijing100083China James Hutton Limited The James Hutton InstituteErrol RoadInvergowrieDundeeDD25DAUK b.omathematics and Statistics Scotland Errol RoadInvergowrieDundeeDD25DAUK Crop Research Centre TeagascOak ParkCarlow R93 XE12Ireland HZPC Research b.V.HZPC Edisonweg 58501 XG JoureNetherlands

Potato is the thirdmost important food crop in *** pathogens threaten sustainab.e crop production b.t can b. controlled,in many cases,through the deployment of disease resistance genes b.longing to the family of nucleotide-b.nding,leucine-rich-repeat(NLR)*** identify effective disease resistance genes in estab.ished varieties,we have successfully estab.ished SMRT-AgRenSeq in tetraploid potatoes and have further enhanced the methodology b. including dRenSeq in an approach that we term *** inclusion of dRenSeq enab.es the filtering of candidates after the association analysis b. estab.ishing a presence/ab.ence matrix across resistant and susceptib.e varieties that is translated into an F1 *** a SMRT-RenSeq-b.sed sequence representation of the NLRome from the cultivar Innovator,SMRT-AgRenSeq-d analyses reliab.y identified the late b.ight resistance b.nchmark genes Rpi-R1,Rpi-R2-like,Rpi-R3a,and Rpi-R3b.in a panel of 117 varieties with variab.e phenotype *** b.nchmark genes were identified with an F1 score of 1,which indicates ab.olute linkage in the *** method also identified nine strong candidates for Gpa5 that controls the potato cyst nematode(PCN)species Glob.dera pallida(pathotypes Pa2/3).Assuming that NLRs are involved in controlling many types of resistances,SMRT-AgRenSeq-d can readily b. applied to diverse crops and pathogen systems.

关键词： resistance linkage crops