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Magnesium research in Canada:Highlights of the last two decades

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Journal of Magnesium and Alloys 2023年第10期11卷 3484-3510页

作者： frank Czerwinski Natural Resources Canada CanmetMATERIALSHamiltonONCanada

The highlights of major Canadian research projects of last two decades that aimed at advancing applications of magnesium and its alloys,being at the heart of lightweighting and ecological sustainability, are outlined. The research at universities, government laboratories, and other dedicated institutions, funded primarily through federal programs, was accompanied by strong activities of the industrial sector involved in designing and building the machinery for magnesium processing and production of components from magnesium alloys. The overall research directions matched the global trends of overcoming the key challenges that prevent magnesium alloys to play the major role in large-scale applications. Among industrially oriented projects the processing technologies in liquid, semisolid and solid states such as casting, twin roll casting, injection molding, rolling, extrusion, forging, and joining techniques were frequently pursued. Although the fundamental research aimed at understanding of a variety of magnesium behaviors and structural peculiarities up to nano and atomic levels, its essence spread around the inherently poor formability and high reactivity at room and elevated temperatures, including the ignition/flammability *** recent years, a shift in research interests was observed and novel directions emerged such as magnesium air batteries, biodegradable alloys, additive manufacturing, and magnesium-rich high entropy alloys. The volume of data gathered in this report may constitute a base for specifically oriented assessments, analyses, and drawing conclusions.

关键词： Magnesium Magnesium alloys Processing technologies Canadian research projects

Ultra-broadband access enabled by fiber optics(Invited Paper)

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Chinese Optics Letters 2016年第12期14卷 17-20页

作者： frank Effenberger Futurewei Technologies Bridgewater NJ 08807 USA

The advent of low loss optical fiber has consistently led us to the ultra-broadband era, where bandwidths exceeding 1 Gb/s are commonplace. This Review reviews the early history of fiber access, pointing out some of the lasting design choices and signature features of fiber access. The progress of the various passive optical network technologies is also reviewed, and some views regarding the future trends of fiber in the access.

关键词： broadband consistently optics pointing signature lasting exceeding deployment bandwidth enabled

Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark B. Neely Francis M. Rouquette Jr. Cristine L.S. Morgan frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha-1) and contributed the most total N (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea

关键词： Annual Legumes Soil N Soil Organic C Green Manure Deer Browse Forage Cropping Systems

Asymptotics and Blow-up for Mass Critical Nonlinear Dispersive Equations(Dedicated to Professor Ham Brezis on the occasion of his 70th birthday)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 579-590页

作者： frank MERLE Universitéde Cergy-pontoise MathématiquesCNRSCNRSF-95000 Cergy-PontoiseFrance Institut des HautesEtudes Scientifiques 35 Route de Chartres91440 Bures-sur-YvetteFrance

The author considers mass critical nonlinear Schrdinger and Korteweg-de Vries equations. A review on results related to the blow-up of solution of these equations is given.

关键词： Dispersive nonlinear PDE, Criticality, Asymptotics, Blow-up, Globalsolution, Soliton

Climatic and non-climatic factors driving the livelihood vulnerability of smallholder farmers in Ahafo Ano North District,Ghana

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Regional Sustainability 2024年第3期5卷 24-39页

作者： frank BAFFOUR-ATA Louisa BOAKYE Moses Tilatob GADO Ellen BOAKYE-YIADOM Sylvia Cecilia MENSAH Senyo Michael KWAKU KUMFO Kofi Prempeh OSEI OWUSU Emmanuel CARR Emmanuel DZIKUNU Patrick DAVIES Department of Environmental Science Kwame Nkrumah University of Science and TechnologyKumasiAK-039-5028Ghana Department of Meteorology and Climate Science Kwame Nkrumah University of Science and TechnologyKumasiAK-039-5028Ghana

Smallholder farmers in Ahafo Ano North District,Ghana,face multiple climatic and non-climatic *** study assessed the factors contributing to the livelihood vulnerability of smallholder farmers in this district by household surveys with 200 respondents and focus group discussions(FGDs)with 10 *** Mann–Kendall trend test was used to assess mean annual rainfall and temperature trends from 2002 to *** relative importance index(RII)value was used to rank the climatic and non-climatic factors perceived by *** socioeconomic characteristics affecting smallholder farmers’perceptions of climatic and non-climatic factors were evaluated by the binary logistic regression *** showed that mean annual rainfall decreased(P>0.05)but mean annual temperature significantly increased(P<0.05)from 2002 to 2022 in the *** key climatic factors perceived by smallholder farmers were extreme heat or increasing temperature(RII=0.498),erratic rainfall(RII=0.485),and increased windstorms(RII=0.475).The critical non-climatic factors were high cost of farm inputs(RII=0.485),high cost of healthcare(RII=0.435),and poor condition of roads to farms(RII=0.415).Smallholder farmers’perceptions of climatic and non-climatic factors were significantly affected by their socioeconomic characteristics(P<0.05).This study concluded that these factors negatively impact the livelihoods and well-being of smallholder farmers and socioeconomic characteristics influence their perceptions of these ***,to enhance the resilience of smallholder farmers to climate change,it is necessary to adopt a comprehensive and context-specific approach that accounts for climatic and non-climatic factors.

关键词： Smallholder farmers Livelihood vulnerability Climate change Socioeconomic characteristics Food security Ghana

Legume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark B. Neely Francis M. Rouquette Jr. Cristine L. S. Morgan frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biomass sorghum production system to evaluate impacts on N concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total N and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and winter fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertilizer treatments (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CPGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. Rate of N fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil N over time indicated mineralization of organic N and may explain why no N fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum Legumes Green Manure Intercrop Cowpea Crimson Clover Soil Organic Carbon Soil Nitrogen

Constructing parametric triangular patches with boundary conditions

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Progress in Natural Science:Materials International 2008年第3期18卷 315-322页

作者： frank Cheng Department of Computer Science University of Kentucky Lexington KY 40506 USA

The problem of constructing a parametric triangular patch to smoothly connect three surface patches is studied. Usually, these surface patches are defined on different parameter spaces. Therefore, it is necessary to define interpolation conditions, with values from the given surface patches, on the boundary of the triangular patch that can ensure smooth transition between different parameter spaces. In this paper we present a new method to define boundary conditions. Boundary conditions defined by the new method have the same param- eter space if the three given surface patches can be converted into the same form through affine transformation. Consequently, any of the classic methods for constructing functional triangular patches can be used directly to construct a parametric triangular patch to connect given surface patches with G1 continuity. The resulting parametric triangular patch preserves precision of the applied classic method.

关键词： Triangular patch Parametric interpolation Determination of interpolation conditions

Poly(ethylene glycol) conjugated nano-graphene oxide for photodynamic therapy

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Science China Chemistry 2010年第11期53卷 2265-2271页

作者： Pilger frank Institute for Advanced Materials and Nano Biomedicine(iNANO) Tongji University

A novel methoxy-poly(ethylene glycol) modified nano-graphene oxide(NGO-mPEG) was designed and synthesized as a photosensitizer(PS) carrier for photodynamic therapy of *** with a size below 200 nm was prepared using a modified Hummers' *** was observed by AFM to exhibit a structure with single-layer graphene oxide sheets down to a few nanometers in *** mPEG conjugation of NGO(NGO-mPEG) was found to enhance solubility in cell culture *** apparent cytotoxicity of the NGO-mPEG was observed towards MCF-7 carcinoma cell *** phthalocyanine(ZnPc),a photosensitizer for photodynamic therapy,was loaded in the NGO-PEG through π-π stacking and hydrophobic interactions,with the drug loading efficiency up to 14 wt%.Hydrophobic ZnPc was internalized in MCF-7 cells,exhibiting a pronounced phototoxicity in the cells under Xe light *** results indicate a great potential of NGO-mPEG for photodynamic therapy of cancer.

关键词： nano-graphene oxide photodynamic therapy photosensitizer drug delivery biomedical application

中国留学生跨文化能力发展探究——以中国在英留学生为例

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武汉冶金管理干部学院学报 2024年第2期34卷 43-47页

作者：徐航张鑫长春光华学院跨文化研究院吉林长春130033 云南师范大学外国语学院云南昆明650500

随着后疫情时代的到来和中美局势的发展,目前英国已经成为中国学生出国留学的首选之地。以20位留英中国学生为研究对象,首先借助Bennett的跨文化敏感性发展模型来剖析他们留学英国过程中的跨文化能力发展状态;进而从Byram的跨文化能力... 详细信息

随着后疫情时代的到来和中美局势的发展,目前英国已经成为中国学生出国留学的首选之地。以20位留英中国学生为研究对象,首先借助Bennett的跨文化敏感性发展模型来剖析他们留学英国过程中的跨文化能力发展状态;进而从Byram的跨文化能力模型视角出发,探讨国内高校在培养学生跨文化能力方面可以从中得到的借鉴和启示。

关键词：中国留学生跨文化能力跨文化敏感性中国在英留学生