检索结果-南通市图书馆

Experimental study on the tribo-chemical smoothening process between self-mated silicon carbide in a water-lubricated surfacecontact reciprocating test

在线全文

学校读者我要写书评

暂无评论

Friction 2019年第2期7卷 181-191页

作者： Le JIN Herbert SCHEERER Georg ANDERSOHN Matthias OECHSNER Dieter HELLMANN Center for Structural Materials Technische Universit?t Darmstadt KSB

Silicon carbide(SiC) can be tribo-chemically smoothened during a self-mated sliding procedure in the aqueous environment. As well reported in the point-contact tests, this smoothening process works well due to the abundant water as oxidant. After this smoothening process, the tribo-surface is well polished, a closely mated tribo-gap naturally forms, and an ultra-low friction state is built. However, water in the tribo-gap could be insufficient in industrial applications, e.g., the seal gap in mechanical seals. In this study, the tribo-chemical smoothening behavior in such environment was researched. A surface-contact reciprocating test was used to simulate the aqueous environment where water was insufficient. After tests, compared to the published results from the point-contact tests, the same ultra-low friction state was achieved. A part of the tribo-surface was tribo-chemically smoothened. The obtained smoothened surface microstructure was consistent with the published information. Meanwhile, severe abrasive wear occurred. A porous oxygen-rich layer was found existing beneath the abrasion-induced grooves, in which numerous smashed wear debris adhered on the worn surfaces. We concluded that the shortage of water initiated the severe abrasion, meanwhile the generated wear debris aggravated the wear condition. This understanding is instructive for developing new methods to avoid the severe abrasion in the same water insufficient environment.

关键词： silicon carbide surface-contact sliding friction tribo-chemical smoothening abrasion ultra-low friction mechanical seal

Multitarget Thiol-Activated Tetrapyridyl Gold(Ⅲ)Complexes for Hypoxic Cancer Therapy

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第3期6卷 783-797页

作者： Xue-Quan Zhou Selda Abyar Imma Carbo-Bague Lan Wang Sebastian Türck Maxime ASiegler Uttara Basu Ingo Ott Rongfang Liu Adriaan PIJzerman Sylvestre Bonnet Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate School(SIGS)Tsinghua UniversityShenzhen 518055 Leiden Institute of Chemistry Leiden University2333 CC Leiden Department of Chemistry Simon Fraser UniversityBurnabyBritish Columbia V5A 1S6 Institute of Medicinal and Pharmaceutical Chemistry Technische Universität Braunschweig38106 Braunschweig Department of Chemistry Johns Hopkins UniversityBaltimoreMaryland 21218 Division of Drug Discovery&Safety Leiden Academic Centre for Drug ResearchLeiden University2333 CC Leiden

Gold complexes have emerged as promising anticancer metallodrugs due to their efficient thioredoxin reductase(TrxR)inhibition,which disturbs the redox balance of cancer ***,in this model,the role of the ligand(s)coordinated to gold is often *** this work,we present a series of tetrapyridyl Au(Ⅲ)complexes that exhibit thiol-induced release of a Au(Ⅰ)ion and a tetrapyridyl *** formation of a free Au(Ⅰ)center is responsible for the expected TrxR ***,the released ligand,which was visible in cells due to its intense blue fluorescence,showed excellent binding properties to the hERG potassium ***,these ligands ended up in the lysosomes,resulting in significant lysosome ***,the Au(Ⅲ)complexes presented in this work showed broad-spectrum anticancer properties,both in hypoxic 2D monolayers and 3D tumor *** suggest that the interaction of the released Au(Ⅰ)center and the tetrapyridyl ligand with two different protein targets may combine into prodrugs that overcome hypoxia-induced drug deactivation.

关键词： anticancer Au(Ⅲ)complexes enzyme inhibtion potassium channel affinity lysosome damage cell imaging prodrug

Space aquatic chemistry:A roadmap for drinking water treatment in microgravity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Environmental Science and Ecotechnology 2024年第3期19卷 26-28页

作者： Baiwen Ma Yaohui Bai Chengzhi Hu Beizhen Xie Junya Zhang Mathias Ulbricht Libing Zheng Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China Lehrstuhl für technische Chemie II Universität Duisburg-EssenEssen45117Germany Institute of Environmental Biology and Life Support Technology School of Biological Science and Medical EngineeringBeihang UniversityBeijing100191China Department of Water Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China Department of Isotope Biogeochemistry Helmholtz Centre for Environmental Research-UFZLeipzig04318Germany

Rapid advancement in aerospace technology has successfully enabled long-term life and economic activities in space,particularly in Low Earth Orbit(LEO),extending up to 2000 km from the mean sea ***,the sustainance of the LEO Economy and its Environmental Control and Life Support System(ECLSS)still relies on a regular cargo supply of essential commodities(e.g.,water,food)from Earth,for which there still is a lack of adequate and sustainable *** key challenge in this context is developing water treatment technologies and standards that can perform effectively under microgravity *** this technical challenge will be a milestone in providing a scientific basis and the necessary support mechanisms for establishing permanent bases in outer space and *** identify clues towards solving this challenge,we looked back at relevant scientific research exploring novel technologies and standards for deep space exploration,also considering feedback for enhancing these technologies on *** our findings,we share our outlook for the future of drinking water treatment in *** also bring up a new concept for space aquatic chemistry,considering the closed environment of engineered systems operating in microgravity.

关键词： Microgravity Drinking water treatment Water quality Challenges Strategies

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Contribution of Fluid Dynamics to Woodwind Instruments Investigations of Timbre and Pitch of Bassoon Bocals

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2005年第3期14卷 264-266页

作者： Roger GRUNDMANN Johannes BAUMGART Andreas RICHTER Hans KRüGER technische Universitt Dresden Institute for Aerospace Engineering D-01062 Dresden Germany ProfessorTechnische Universitt Dresden Institute for Aerospace Engineering D-01062 Dresden GermanyTechnische Universitt Dresden Institute for Aerospace Engineering D-01062 Dresden GermanyTechnische Universit?t Dresden Institute for Aerospace Engineering D-01062 Dresden Germany

The discussed topic of isolating certain parameters which describe the timbre in connection with bocals of bassoons is of major interest for manufacturers and artist likewise since a reduction in the overall shear stress of these kinds of technical diffusors is very helpful but not sufficient. The timbre seen from the side of the musician has to be the same. Up to now two criteria have been isolated which have a deep influence on the easier blowing of the bassoon and on the comparable timbre due to geometrical reasons. If the geometrical outer contour is designed carefully, it is possible to modify the shape and preserve the timbre.

关键词： musical instrument bocal bassoon timbre principal component analysis

Influence of High-Speed Milling Process on Mechanical and Microstructural Properties of Ultrafine Grained Profiles Produced by Linear Flow Splitting

在线全文

学校读者我要写书评

暂无评论

Transactions of Nanjing University of Aeronautics and Astronautics 2017年第4期34卷 349-356页

作者： Abele Eberhard Müller Clemens Turan Emrah Niehuesbernd Joern Bruder Enrico Falk Florian Institute of Production Management Technology and Machine Tools(PTW)Technische Universitt Darmstadt Physical Metallurgy(PhM) Technische Universitt Darmstadt

The effects of milling parameters on the surface quality,microstructures and mechanical properties of machined parts with ultrafine grained(UFG)gradient microstructures are *** effects of the cutting speed,feed per tooth,cutting tool geometry and cooling strategy are *** has been found that the surface quality of machined grooves can be improved by increasing the cutting ***,cryogenic cooling with CO_2 exhibits no significant improvement of surface *** and hardness investigations revealed similar microstructure and hardness variations near the machined groove walls for both utilized tool ***,cryogenic cooling can decrease more far-ranging hardness reductions due to high process temperatures,especially in the UFG regions of the machined parts,whilst it cannot prevent the drop in hardness directly at the groove walls.

关键词： high-speed milling ultrafine grained microstructure linear flow splitting hardness

Toward Shared Control Between Automated Vehicles and Users

在线全文

学校读者我要写书评

暂无评论

Automotive Innovation 2020年第1期3卷 53-61页

作者： Jacques Terken Bastian Pfleging technische Universiteit Eindhoven EindhovenThe Netherlands

Technological developments in the domain of vehicle automation are targeted toward driver-less,or driver-out-of-the-loop *** main societal motivation for this ambition is that the majority of(fatal)accidents with manually driven vehicles are due to human ***,when interacting with technology,users often experience the need to customize the technology to their personal *** paper considers how this might apply to vehicle automation,by a conceptual analysis of relevant use *** analysis proceeds by comparing how handling of relevant situations is likely to differ between manual driving and automated *** results of the analysis indicate that full out-of-the-loop automated driving may not be acceptable to users of the *** is concluded that a technology that allows shared control between the vehicle and the user should be ***,implications of this view are explored for the concrete temporal dynamics of shared control,and general characteristics of human machine interface that support shared control are ***,implications of the proposed view and directions for further research are discussed.

关键词： Automated driving Shared control Human machine interface

A MULTIGRID SEMISMOOTH NEWTON METHOD FOR SEMILINEAR CONTACT PROBLEMS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2017年第4期35卷 486-528页

作者： Michael Ulbrich Stefan Ulbrich Daniela Bratzke technische Universitat Miinchen Department of Mathematics Garching b. Munchen Germany technische Universitiit Darmstadt Department of Mathematics Darmstadt Germany technische Universitat Darmstadt Department of Mathematics Darmstadt Germany

This paper develops and analyzes multigrid semismooth Newton methods for a class of inequality-constrained optimization problems in function space which are motivated by and include linear elastic contact problems of Signorini type. We show that after a suitable Moreau-Yosida type regularization of the problem superlinear local convergence is obtained for a class of semismooth Newton methods. In addition, estimates for the order of tile error introduced by the regularization are derived. The main part of the paper is devoted to the analysis of a multilevel preconditioner for the semismooth Newton system. We prove a rigorous bound for the contraction rate of the multigrid cycle which is robust with respect to sufficiently small regularization parameters and the number of grid levels. Moreover, it applies to adaptively refined grids. The paper concludes with numerical results.

关键词： Contact problems Semismooth Newton methods Multigrid methods Errorestimates.

Molecularly horizontal stacking benefits charge separation through delocalized charge transfer states at donor-acceptor interfaces

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecularly horizontal stacking benefits charge separation t...