检索结果-南通市图书馆

Light metal compound casting

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2009年第1期52卷 46-51页

作者： konrad j. m. papis joerg F. LOEFFLER Peter j. UGGOWITZER ETH Zurich Laboratory of Metal Physics and Technology Wolfgang-Pauli-Str. 10

‘Compound casting’simplifies joining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as joint structures of spaceframe constructions in transport industry. In this project, ‘compound casting’ of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu- ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the joining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3mg2 and Al12mg17 ImPs) at the interface of Al-mg couples was avoided by applying a protective coating to the substrate.

关键词： compound casting aluminium alloys magnesium alloys interface structure

Cathodic activated stainless steel mesh as a highly active electrocatalyst for the oxygen evolution reaction with self-healing possibility

在线全文

学校读者我要写书评

暂无评论

journal of Energy Chemistry 2020年第10期29卷 153-160页

作者： Gui-Rong Zhang Liu-Liu Shen Patrick Schmatz konrad Krois Bastian j.m.Etzold Ernst-Berl-Institut für Technische und makromolekulare Chemie Technische Universit鋞Darmstadt64287 DarmstadtGermany

The oxygen evolution reaction(OER)represents one of the major bottlenecks for broad-based applications of many clean energy storage/conversion *** key to solving this problem lies in developing high-performing,cost effective and stable catalysts for the ***,we demonstrate that ubiquitous stainless steel mesh(SSm)materials activated by a facile cathodization treatment can be employed as a high performing OER catalyst,as showcased by the impressively low overpotentials of 275 and 319 mV to reach the benchmark current densities of 10 and 100 mA cm^−2(1.0 m KOH),*** SSm also exhibits excellent performance in a two-electrode water electrolyzer,which requires a low cell voltage of 1.58 at 10 mA cm^−2 and outperforms many of water electrolyzers using earth-abundant OER ***,cathodized SSm with minor performance degradation after the stability test can also be readily healed by subjecting it to an additional cathodization *** is disclosed that the superior performance of cathodized SSms stems from the surface enrichment of OER active Ni(oxy)hydroxide,facile gas-bubble removal and transportation over the unique mesh-structured surfaces,while the abundant reservoir of nickel in the bulk allows healing of the catalyst by a facile cathodization.

关键词： Oxygen evolution reaction Water splitting Stainless steel mesh Cathodization mass transfer limitation Self-healing

在线全文

学校读者我要写书评

暂无评论

E8粒子的自旋动力学研究（英文）

Science Bulletin 2024年第19期 2974-2977页

作者：王骁 konrad Puzniak Karin Schmalzl Christian Balz masaaki matsuda Akira Okutani masayuki Hagiwara 马杰吴建达 Bella Lake Tsung-Dao Lee Institute Shanghai Jiao Tong University Helmholtz-Zentrum Berlin für materialien und Energie GmbH Institut für Festk?rperphysik Technische Universit?t Berlin jülich Centre for Neutron Science jCNS Forschungszentrum Jülich GmbH ISIS Neutron and muon Source STFC Rutherford Appleton Laboratory Neutron Scattering Division Oak Ridge National Laboratory Center for Advanced High magnetic Field Science Graduate School of ScienceOsaka University School of Physics&Astronomy Shanghai Jiao Tong University Collaborative Innovation Center of Advanced microstructures Nanjing University Shanghai Branch Hefei National Laboratory

Unlike the classical phase transition driven by thermal fluctuations,the quantum phase transition arises at zero temperature when the system is tuned by a non-thermal parameter[1].For a continuous quantum phase transition,novel physics with higher symmetry may emerge at the quantum critical point (QCP).As the system is driven away from the QCP with a relevant perturbation,exotic physics may further emerge due to the strong renormalization of the almost infinite low-lying excitations[2].The transverse-field Ising chain (TFIC) is a paradigmatic model[1–3]:when an Ising chain is tuned to its QCP by a magnetic field applied transverse to its Ising anisotropy,

关键词：

multiphoton synthetic lattices in multiport waveguide arrays: synthetic atoms and Fock graphs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2020年第7期8卷 1161-1170页

作者： konrad Tschernig Roberto de j.León-montiel Armando Pérez-Leija Kurt Busch max-Born-Institut 12489 BerlinGermany Instituto de Ciencias Nucleares Universidad Nacional Autónoma de MéxicoApartado Postal 70-54304510 Cd.Mexico CityMexico Humboldt-Universität zu Berlin Institut für PhysikAG Theoretische Optik&Photonik12489 BerlinGermany

Activating transitions between internal states of physical systems has emerged as an appealing approach to create lattices and complex *** such a scheme,the internal states or modes of a physical system are regarded as lattice sites or network nodes in an abstract space whose dimensionality may exceed the systems’apparent(geometric)*** introduces the notion of synthetic dimensions,thus providing entirely novel pathways for fundamental research and ***,we analytically show that the propagation of multiphoton states through multiport waveguide arrays gives rise to synthetic dimensions where a single waveguide system generates a multitude of synthetic *** these synthetic lattices exist in photon-number space,we introduce the concept of pseudo-energy and demonstrate its utility for studying multiphoton interference ***,the spectrum of the associated pseudo-energy operator generates a unique ordering of the relevant *** with generalized pseudo-energy ladder operators,this allows for representing the dynamics of multiphoton states by way of pseudo-energy term diagrams that are associated with a synthetic *** a result,the pseudo-energy representation leads to concise analytical expressions for the eigensystem of N photons propagating through m nearest-neighbor coupled *** the regime where N≥2 and m≥3,nonlocal coupling in Fock space gives rise to hitherto unknown all-optical dark states that display intriguing nontrivial dynamics.

关键词： synthetic dimensions system

Combining Contactless Inductive Flow Tomography and mutual Inductance Tomography for Two-Phase Flow measurements at a Continuous Casting model

在线全文

学校读者我要写书评

暂无评论

journal of Iron and Steel Research International 2012年第S1期19卷 479-482页

作者： STEFANI Frank ECKERT Sven GERBETH Gunter KLOTSCHE konrad TImmEL Klaus WONDRAK Thomas PEYTON Anthony j. TERZIjA Natasa YIN Wuliang Helmholtz-Zentrum Dresden-Rossendorf P.O.Box 510119Dresden D-01314Germany School of Electrical and Electronic Engineering The University of ManchesterP.O.Box 88Sackville Street Manchester M13 9PLUK

The flow structure in the mould of a continuous caster is of key importance for the quality of the final product. The use of most conventional flow measurement techniques is prevented by the high temperature of the liquid *** a downscaled physical model of the continuous casting process,we present combined measurements of the flow in the mould by Contacfless Inductive Flow Tomography(CIFT),and of the conductivity distribution in the submerged entry nozzle by mutual Inductance Tomograpliy(mIT).In addition,we summarize an experiment with a magnetic stirrer around the submerged entry nozzle and its effects on the flow in the *** new developments towards a robust implementation of CIFT at a real caster,including the use of pickup coils and gradiometric probes,are also discussed.

关键词： continuous casting flow measurements tomography

Are Ni/and Ni5Fe1/biochar catalysts suitable for synthetic natural gas production?A comparison with g-Al2O3 supported catalysts

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2023年第3期8卷 744-756页

作者： m.Gonzalez-Castano C.morales j.C.Navarro de miguel j.H.Boelte O.Klepel j.I.Flege H.Arellano-García Department of Process and Plant Technology Brandenburg University of Technology(BTU)Cottbus-SenftenbergPlatz der Deutschen 1Cottbus03046Germany Applied Physics and Semiconductor Spectroscopy Brandenburg University of Technology Cottbus-SenftenbergKonrad-Zuse-Strasse 1Cottbus03046Germany Department of Inorganic Chemistry Institute of Materials Science of SevilleConsejo Superior de Investigaciones Cientificas(CSIC)Universidad de Sevilla(US)Avenida Americo Vespucio 49Seville41092Spain Institute of materials Chemistry Brandenburg University of Technology Cottbus–SenftenbergUniversitatsplatz 1SenftenbergD-01968Germany

Among challenges implicit in the transition to the post-fossil fuel energetic model,the finite amount of resources available for the technological implementation of CO_(2) revalorizing processes arises as a central *** development of fully renewable catalytic systems with easier metal recovery strategies would promote the viability and sustainability of synthetic natural gas production circular *** Ni and NiFe catalysts supported over g-Al_(2)O_(3) oxide as reference materials,this work evaluates the potentiality of Ni and NiFe supported biochar catalysts for CO_(2) *** development of competitive biochar catalysts was found dependent on the creation of basic sites on the catalyst *** lower Turn Over Frequencies than Ni/Al catalyst,the absence of basic sites achieved over Ni/C catalyst was related to the depleted catalyst *** NiFe catalysts,analogous Ni_(5)Fe_(1) alloys were constituted over both alumina and biochar *** highest specific activity of the catalyst series,exhibited by the NiFe/C catalyst,was related to the development of surface basic sites along with weaker NiFe-C interactions,which resulted in increased Ni0:NiO surface populations under reaction *** summary,the present work establishes biochar supports as a competitive material to consider within the future low-carbon energetic panorama.

关键词： Biochar catalysts Carbon catalysts Ni catalysts NiFe alloy Bimetallic catalysts Synthetic natural gas CO_(2)methanation

Experimental and modeling Study of Forest Fire Effect on Soil Thermal Conductivity

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2016年第4期26卷 462-473页

作者： Kathleen m.SmITS Elizabeth KIRBY William j.mASSmAN Larry Scott BAGGETT Center for the Experimental Study of Subsurface Environmental Processes Department of Civil and Environmental EngineeringColorado School of Mines USDA Forest Service Rocky Mountain Research Station

An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited. The purpose of this study was to evaluate the long-term impact of fire on the effective thermal conductivity of soils by directly comparing fire-heated and no-fire control soils through a series of laboratory studies. The thermal conductivity was measured for ten soil samples from two sites within the manitou Experimental Forest, Colorado, USA, for a range of water contents from saturation to the residual degree of saturation. The thermal conductivity measured was compared with independent estimates made using three empirical models from literature, including the Campbell et al. （1994）, CSt~ and konrad （2005）, and massman et al. （2008） models. Results demonstrate that for the test soils studied, the thermal conductivity of the fire-heated soils was slightly lower than that of the control soils for all observed water contents. modeling results show that the Campbell et al. （1994） model gave the best agreement over the full range of water contents when proper fitting parameters were employed. Further studies are needed to evaluate the significance of including the influence of fire burn on the thermal properties of soils in modeling studies.

关键词： controlled burn degree of saturation empirical model water content wildfire

CXCR5^(+)PD-1^(++)CD4^(+)T cells colonize infant intestines early in life and promote B cell maturation

在线全文

学校读者我要写书评

暂无评论

Cellular & molecular Immunology 2023年第2期20卷 201-213页

作者： Ana jordan-Paiz Glòria martrus Fenja L.Steinert max Kaufmann Adrian F.Sagebiel Renée R.C.E.Schreurs Anne Rechtien martin E.Baumdick johannes m.jung Kimberly j.möller Lucy Wegner Cordula Grüttner Laura Richert Roland Thünauer jennifer Schroeder-Schwarz johannes Bvan Goudoever Teunis B.H.Geijtenbeek marcus Altfeld Steven T.Pals Daniel Perez Paul L.Klarenbeek Christian Tomuschat Guido Sauter Ingo Königs Udo Schumacher manuel A.Friese Nathaniel melling konrad Reinshagen madeleine j.Bunders Department of Virus Immunology Leibniz Institute of VirologyHamburg20251Germany University medical Center Hamburg-Eppendorf Hamburg20246Germany Institute of Neuroimmunology and multiple Sclerosis Center for Molecular Neurobiology HamburgUniversity Medical Center Hamburg-EppendorfHamburg20251Germany Department of General Visceral and Thoracic SurgeryUniversity Medical Center Hamburg-EppendorfHamburg20246Germany Department of Experimental Immunology Amsterdam Infection&Immunity InstituteAmsterdam University Medical CenterUniversity of AmsterdamAmsterdam1105 AZThe Netherlands Department of Pediatrics Emma Children’s HospitalAmsterdam University Medical CenterUniversity of Amsterdam and Vrije Universiteit AmsterdamAmsterdam1105 AZThe Netherlands I.Department of medicine University Medical Center Hamburg-EppendorfHamburg20246Germany Partner Site Hamburg-Lübeck-Borstel-Riems German Center for Infection Research(DZIF)Hamburg20246Germany University of Bordeaux Institut National de la Santéet de la Recherche MédicaleBordeaux Population Health Research Center UMR1219 and INRIA SISTM TeamBordeaux33000France Institute of Anatomy and Experimental morphology University Medical Center Hamburg-EppendorfHamburg20246Germany Department of Pathology Amsterdam University Medical CenterUniversity of AmsterdamAmsterdam1105 AZThe Netherlands Department of Rheumatology and Clinical Immunology and Department of Experimental Immunology Amsterdam Infection&Immunity InstituteAmsterdam University Medical CenterUniversity of AmsterdamAmsterdam1007 MBThe Netherlands Amsterdam Rheumatology&Immunology Center Amsterdam University Medical CenterUniversity of AmsterdamAmsterdam1105 AZThe Netherlands Department of Pediatric Surgery University Medical Center Hamburg-EppendorfHamburg20246Germany Institute of Pathology University Medical Center Hamburg-EppendorfHamburg20246Germany Department of Pediatric Surgery Altona Children’s HospitalHamburg22763Germany III.Department of medicine University M

Gastrointestinal infections are a major cause for serious clinical complications in *** induction of antibody responses by B cells is critical for protective immunity against infections and requires CXCR5+PD-1++CD4+T cells(TFH cells).We investigated the ontogeny of CXCR5+PD-1++CD4+T cells in human *** CXCR5+PD-1++CD4+T cells were absent in fetal intestines,CXCR5+PD-1++CD4+T cells increased after birth and were abundant in infant intestines,resulting in significant higher numbers compared to *** findings were supported by scRNAseq analyses,showing increased frequencies of CD4+T cells with a TFH gene signature in infant intestines compared to ***-cultures of autologous infant intestinal CXCR5+PD-1+/−CD4+T cells with B cells further demonstrated that infant intestinal TFH cells were able to effectively promote class switching and antibody production by B *** together,we demonstrate that functional TFH cells are numerous in infant intestines,making them a promising target for oral pediatric vaccine strategies.

关键词： TFH cells B cells Antibodies Intestine Pediatrics

茶碱对人工呼吸监护病人粘液纤毛净化功能的影响

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

德国医学 1995年第2期12卷 120-121页

作者： F.konrad T.Schreiber j.Hhnel j.Kilian m.Georgieff 李树生 Universitatsklinik für Anasthesiologie Klinikum der Universitat UlmSteinhovelstr.9D-89075 UlmGermany 同济医科大学附属同济医院

粘液纤毛净化功能将吸入的有害物质或微生物从气管、支气管腔内清除,是肺重要的非特异性保护机制之一。纤毛上皮和具有粘性弹性特征的粘液之间复杂的协同作用,对维护这一功能的正常进行,具有重要意义。最近研究指出,分泌物潴留成为细菌... 详细信息

粘液纤毛净化功能将吸入的有害物质或微生物从气管、支气管腔内清除,是肺重要的非特异性保护机制之一。纤毛上皮和具有粘性弹性特征的粘液之间复杂的协同作用,对维护这一功能的正常进行,具有重要意义。最近研究指出,分泌物潴留成为细菌的容库,导致微生物的持续存在和细菌的繁殖。当呼吸道上皮完整时,许多潜在的致病微生物都不能粘附和形成集落,而必须有粘膜和上皮损伤。正如我们过去研究所指出:人工呼吸监护病人支气管运输速率(BTG)常受到损害,这种防御功能的受累,往往与出现分泌物潴留和医源感染性肺炎有关。

关键词：茶碱人工呼吸监护粘液纤毛净化功能临床应用