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Reproducibility of deposition and industrial applications of stable superhard nanocomposites

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 19-24页

作者： stan Veprek department for Chemistry Technical University Munich Lichtenbergstr. 4 D-85747 Garching b. Munich Germany

After a brief introduction regarding the different approaches to superhard coatings we shall concentrate on the problem of the reproducibility of the deposition of superhard and thermally very stable nanocomposites according to the design principle published by Veprek and Reiprich in 1995. It will be shown that either the choice of inappropriate deposition conditions, in contradiction to our design principle, or impurities in the coatings are the reason for the lack of reproducibility of our earlier results by many other workers. We shall also briefly summarize the recent industrial applications.

关键词： superhard nanocomposite reproducibility of deposition industrial application

Revealing the Pressure-Induced Softening/Weakening Mechanism in Representative Covalent Materials

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Chinese Physics Letters 2021年第5期38卷 51-59页

作者： Tengfei Xu Shihao Zhang dominik Legut stan Veprek Ruifeng Zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China Center for Integrated Computational Engineering(International Research Institute for Multidisciplinary Science)and Key Laboratory of High-Temperature Structural Materials&Coatings Technology(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China IT4Innovations VSB-Technical University of Ostrava17 listopadu 2172/1570800 OstravaCzech Republic department of Chemistry Technical University MunichLichtenbergstr 4D-85747 GarchingGermany

diamond, cubic boron nitride(c-BN), silicon(Si), and germanium(Ge), as examples of typical strong covalent materials, have been extensively investigated in recent decades, owing to their fundamental importance in material science and industry. However, an in-depth analysis of the character of these materials' mechanical behaviors under harsh service environments, such as high pressure, has yet to be conducted. Based on several mechanical criteria, the effect of pressure on the mechanical properties of these materials is comprehensively *** is demonstrated that, with respect to their intrinsic brittleness/ductile nature, all these materials exhibit ubiquitous pressure-enhanced ductility. By analyzing the strength variation under uniform deformation, together with the corresponding electronic structures, we reveal for the first time that the pressure-induced mechanical softening/weakening exhibits distinct characteristics between diamond and c-BN, owing to the differences in their abnormal charge-depletion evolution under applied strain, whereas a monotonous weakening phenomenon is observed in Si and Ge. Further investigation into dislocation-mediated plastic resistance indicates that the pressure-induced shuffle-set plane softening in diamond(c-BN), and weakening in Si(Ge), can be attributed to the reduction of antibonding states below the Fermi level, and an enhanced metallization, corresponding to the weakening of the bonds around the slipped plane with increasing pressure, respectively. These findings not only reveal the physical mechanism of pressure-induced softening/weakening in covalent materials, but also highlights the necessity of exploring strain-tunable electronic structures to emphasize the mechanical response in such covalent materials.

关键词： red service Revealing the Pressure-Induced Softening/Weakening Mechanism in Representative Covalent Materials

Highly luminescent europium and terbium complexes based on succinimide and N-hydroxysuccinimide

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Journal of Rare Earths 2012年第5期30卷 401-407页

作者： Corneliu Sergiu stan Ioan Rosca daniel Sutiman Marius Sebastian Secula Faculty of Chemical Engineering and Environmental Protection Gheorghe Asachi Technical University of Iasi73 D.Mangeron700050IasiRomania

The preparation of two highly luminescent europium（Ill） and terbium（Ill） complexes with succinimide （SI） and N-hydroxysuccinimide （NHSI） were reported, which were further investigated through elemental chemical analysis, thermal analysis, FT-IR, powder X-ray diffraction, SEM and fluorescence spectroscopy. data collected through these analysis revealed the formation of the Eu（III） and Th（III） complexes with the above mentioned ligands at a metal to ligand （M：L） molar ratio of 1：3. Interesting conclusions regarding the effi- cient sensitization through the coordination site of the lanthanide luminescent centers were retained from the photoluminescent spectra inves- tigation. Strong luminescence emission was observed in case of Eu（III）-SI and Tb（III）-NHSI complexes while the corresponding Eu（III）-NHSI and Tb（III）-SI complexes exhibited no photo luminescent properties. Newly obtained luminescent lanthanide complexes may be of particular interest for various applications in optoelectronics.

关键词： lanthanide complex succinimide N-hydroxysuccinimide luminescence rare earths

Plant Biosystems design for a Carbon-Neutral Bioeconomy

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Biodesign Research 2020年第1期2020卷 48-52页

作者： Udaya C.Kalluri Xiaohan Yang stan d.wullsc.leger Biosciences division Oak Ridge National LaboratoryPO Box 2008Oak RidgeTN 37831-6422USA Environmental Sciences division Oak Ridge National LaboratoryPO Box 2008Oak RidgeTN 37831-6422USA

Our society faces multiple daunting challenges including finding sustainable solutions towards climate change mitigation;efficient production of food,biofuels,and biomaterials;maximizing land-use efficiency;and enabling a sustainable *** can provide environmentally and economically sustainable solutions to these challenges due to their inherent capabilities for photosynthetic capture of atmospheric CO2,allocation of carbon to various organs and partitioning into various chemical forms,including contributions to total soil *** order to enhance crop productivity and optimize chemistry simultaneously in the above-and belowground plant tissues,transformative biosystems design strategies are *** research efforts will be required for accelerating the development of plant cultivars,genotypes,or varieties that are cooptimized in the contexts of biomass-derived fuels and/or materials aboveground and enhanced carbon sequestration ***,we briefly discuss significant knowledge gaps in our process understanding and the potential of synthetic biology in enabling advancements along the fundamental to applied research ***,a convergence of perspectives from academic,industrial,government,and consumer sectors will be needed to realize the potential merits of plant biosystems design for a carbon neutral bioeconomy.

关键词： neutral sustainable enabling

Hybrid energy module for remote environmental observations, experiments, and communications

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Advances in Polar Science 2020年第3期31卷 156-166页

作者： Misha B.KRASSOVSKI Jeffery S.RIGGS Chris TAVINO stan d.wullsc.leger Susan L.HEINZ Environmental Sciences division Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTN 37831-6290USA Integrated Operations Support division Oak Ridge National LaboratoryOak RidgeTN 37831-6290USA Laboratory Modernization division Oak Ridge National LaboratoryOak RidgeTN 37831-6290USA

Increased concerns about climate change have led to a significant expansion of monitoring, observational, and experimental sites in remote areas of the world. Meanwhile, advances in technology and availability of low-power equipment have allowed increasingly sophisticated measurements with a wide variety of instruments. However, the deployment and use of these technologies in remote locations is often restricted not only by harsh environmental conditions, but also by the availability of electrical power and communication options. In some cases, research stations and military installations can provide power for scientific equipment, data acquisition, storage, and transmission. Clustering of research sites near existing infrastructure has had the unintended consequence of limiting a spatial understanding of large geographic regions. Fortunately, the modern market offers many power and communication solutions, but most of them are oriented toward large industrial applications. Use of those solutions to power a research site is limited because of their cost and need for significant modification for the specific research purposes. Each study has its own unique power requirements and needs for proper instrumentation. A power and communication solution for a vast majority of implementations with or without modification would be of considerable benefit. This article describes design of a universal, scalable hybrid energy module for the Next-Generation Ecosystem Experiments Arctic project(https://***/). Two modules were built, and the authors describe their implementation and findings over a 2-year period at a remote field site on the Seward Peninsula in western Alaska, USA.

关键词： solar energy wind energy communications power sources alternative energy NGEE Arctic

Inside the Light Boojums: a Journey to the Land of Boundary defects

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Analysis in Theory and Applications 2020年第2期36卷 128-160页

作者： stan Alama Lia Bronsard Petru Mironescu department of Mathematics&Statistics McMaster UniversityHamiltonOntarioL8S 4K1 Canada Universit'e de Lyon CNRS UMR 5208Universit´e Lyon 1Institut Camille Jordan43 blvd.du 11 Novembre 1918F-69622 Villeurbanne CedexFrance

We consider minimizers of the energy Eε(u)=:∫Ω[1/2|■u|^2+1/4ε2(|u|^2-1)^2]dx+1/2ε^s∫■ΩW(u,g)ds,u:Ω→■,0-cosα)^2,0derived as a thin-film limit of the Landau-de Gennes ene... 详细信息

We consider minimizers of the energy Eε(u)=:∫Ω[1/2|■u|^2+1/4ε2(|u|^2-1)^2]dx+1/2ε^s∫■ΩW(u,g)ds,u:Ω→■,0dimensional domain W,with weak anchoring potential W(u,g)=:1/2(|u|^2-1)^2+(-cosα)^2,0derived as a thin-film limit of the Landau-de Gennes energy,assuming weak anchoring on the boundary favoring a nematic director lying along a cone of fixed aperture,centered at the normal vector to the *** the regime where s[α^2+(π-α)^2]dary vortices,where its phase jumps by either 2α(light boojums)or 2(π-α)(heavy boojums).Our main result is the fine-scale description of the light boojums.

关键词： Nematics thin-film limit Ginzburg-Landau type energy weak anchoring boundary vortices asymptotic profile

Understanding temporal stability:a long-term analysis of USdA ARS watersheds

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International Journal of digital Earth 2021年第10期14卷 1243-1254页

作者： Evan J.Coopersmith Michael H.Cosh Patrick J.Starks david d.Bosch Chandra Holifield Collins Mark Seyfried stan Livingston John Prueger Soil Insight LLCWashington D.C.USA USdA-Agricultural Research Service Beltsville Agricultural Research CenterHydrology and Remote Sensing LaboratoryBeltsvilleUSA USdA-Agricultural Research Service-Grazinglands Research Laboratory El RenoUSA USdA-Agricultural Research Service-Southeast Watershed Research Laboratory TiftonUSA USdA-Agricultural Research Service-Southwest Watershed Research Center TucsonUSA USdA-Agricultural Research Service-Northwest Watershed Research Laboratory BoiseUSA USdAAgricultural Research Service-National Soil Erosion Research Laboratory West LafayetteUSA USdA-Agricultural Research Service-National Laboratory for Agriculture and Environment AmesUSA

The *** of Agriculture’s Agricultural Research Service(USdAARS)maintains seven in situ soil moisture networks throughout the continental United States,some since *** networks are crucial for understanding the spatial and temporal extent of droughts in their historical context,parameterization of hydrologic models,and local agricultural decision ***,the estimates from these networks are dependent upon their ability to provide reliable soil moisture information at a large *** is also not known how many network stations are sufficient to monitor watershed scale ***,the objectives of this research were to:(1)determine how temporally stable these networks are,including the relationships between various sensors on a year-to-year and seasonal basis,and(2)attempt to determine how many sensors are required,within a network,to approximate the full network *** data from seven in situ,it is concluded that approximately 12 soil moisture sensors are sufficient in most environments,presuming their locations are distributed to capture the hydrologic heterogeneity of the *** is possible to install a temporary network containing a suitable number of sensors for an appropriate length of time,glean stable relationships between locations,and retain these insights moving forward with fewer sensor resources.

关键词： Soil moisture temporal stability in situ networks

New solutions for combatting implant bacterial infection based on silver nano-dispersed and gallium incorporated phosphate bioactive glass sputtered films:A preliminary study

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Bioactive Materials 2022年第2期7卷 325-340页

作者： B.W.Stuart G.E.stan A.C.Popa M.J.Carrington I.Zgura M.Necsulescu d.M.Grant m.grantadvanced materials research group faculty of engineeringuniversity of nottinghamnottinghamng72rduk national institute of materials physics magurelero077125romania army centre for medical research bucharestro010195romania

Ag/Ga were incorporated into resorbable orthopaedic phosphate bioactive glasses(PBG,containing P,Ca,Mg,Na,and Fe)thin films to demonstrate their potential to limit growth of Staphylococcus aureus and Escherichia coli in post-operative prosthetic *** target consecutive co-sputtering was uniquely employed to produce a 46 nm Ag:PBG composite observed by high resolution TEM to consist of uniformly dispersed~5 nm metallic Ag nano-particles in a glass ***^(3+)was integrated into a phosphate glass preform target which was magnetron sputtered to film thicknesses of~400 or 1400 *** coatings exhibited high surface energy of 75.4-77.3 mN/m,attributed to the presence of hydrolytic P-O-P structural surface *** profiles obtained in deionized water,nutrient broth and cell culture medium showed varying ion release profiles,whereby Ga release was measured in 1400 nm coating by ICP-MS to be~6,27,and 4 ppm respectively,fully dissolving by 24 *** of Ag nanoparticles was only observed in nutrient broth(~9 ppm by 24 h).Quantification of colony forming units after 24 h showed encouraging antibacterial efficacy towards both ***(4-log reduction for Ag:PBG and 6-log reduction for Ga-PBG≈1400 nm)and ***(5-log reduction for all physical vapour deposited layers)*** Hs27 fibroblast and mesenchymal stem cell line in vitro tests indicated good cytocompatibility for all sputtered layers,with a marginal cell proliferation inertia in the case of the Ag:PBG composite thin *** study therefore highlights the(i)significant manufacturing development via the controlled inclusion of metallic nanoparticles into a PBG glass matrix by dual consecutive target co-sputtering and(ii)potential of PBG resorbable thin-film structures to incorporate and release cytocompatible/antibacterial *** architectures showed prospective bio-functional performance for a future generation of endo-osseous implant-type coatings.

关键词： Phosphate bioactive glass Silver Gallium Antibacterial Implant coating Magnetron sputtering

Roadmap toward the metaverse: An AI perspective

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The Innovation 2022年第5期3卷 23-24页

作者： Shenghui Cheng Yue Zhang Xiaofei Li Lin Yang Xin Yuan stan Z.Li AI division School of EngineeringWestlake UniversityHangzhou 310024China

Truth must be told,but not much—a hybrid society of real and virtual is ***,1 rise recently,is attracting significant attention from academia to industry.A metaverse is a network of three-dimensional(3d)virtual worlds focused on social *** the outbreak of the coronavirus 2019 pandemic,people are physically isolated,which triggered the growth of the *** from existing work,this commentary targets the roadmap of the metaverse from an artificial intelligence(AI)***,we blueprint a roadmap for this digital cyberspace transformation,including immersion creation,hardware support,text interpretation,audio processing,connection construction,economy operation,and security ***,at each phase of the roadmap,we address the status as well as the advanced technologies to provide indepth views *** whole pipeline is illustrated from an AI2 perspective,as shown in Figure 1,and we believe that AI is playing an increasingly important role in core techniques toward this technological singularity。

关键词： Figure attracting singularity