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A review of challenges and opportunities in micropillar compression studies in Mg alloys

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Journal of Magnesium and Alloys 2023年第11期11卷 4043-4053页

作者： A.Kodam M.S.Gundi Y.L.Chiu i.p.jones S.S.Singh J.Jain Department of Materials Science and Engineering Indian Institute of Technology DelhiNew Delhi 110016India School of Metallurgy and Materials University of BirminghamEdgbastonBirmingham B152TTUK Department of Materials Science and Engineering Indian Institute of Technology KanpurUttar Pradesh 208016India

This review paper provides an overview of the micropillar compression technique as applied to magnesium(Mg) and its alloys. it explores the influence of various factors, such as pillar size, shape, temperature, and strain rate on the mechanical properties of ***, the impact of alloying elements, aging, and precipitates in Mg alloys has been extensively examined, revealing their significant influence on mechanical performance. The study highlights the strength and strain hardening improvements in Mg with decreasing pillar size in micropillar compression. Furthermore, the role of precipitates as strengthening agents, affecting deformation mechanisms and overall mechanical response, is explored. These valuable insights are crucial for designing Mg-based materials with enhanced mechanical properties for advanced engineering applications.

关键词： A review of challenges and opportunities in micropillar compression studies in Mg alloys

perspectives for the recovery of rare earths from end-of-life fluorescent lamps

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Journal of Rare Earths 2014年第3期32卷 195-200页

作者： K.Binnemans p.T.jones Department of Chemistry KU Leuven – University of LeuvenCelestijnenlaan 200F- box 2404 B-3001 Heverlee Belgium Department of Metallurgy and Materials Engineering KU Leuven – University of LeuvenKasteelpark Arenberg 44 - box 2450 B-3001 Heverlee Belgium

This vision paper discusses the advantages and disadvantages of the three main options for the recycling of rare-earth ele- ments from end-of-life fluorescent lamps：（1） direct re-use of the lamp phosphor mixture; （2） separation of the lamp phosphor mixture into the different phosphor components; （3） recovery of the rare-earth content. An overview is given of commercial activities in Europe in the domain of recycling of materials from end-of-life fluorescent lamps and the recovery of rare earths from these lamps. The collection of end-of-life fluorescent lamps is currently driven by a legal framework that prohibited the release of mercury to the environment. The contaminations of the lamp phosphor powders by mercury and by small glass particles of crushed fluorescent lamps are limiting factors in the recycling process. Research should be directed to an advanced clean-up of the reclaimed lamp phosphor fraction, and in particular to the removal of mercury and glass fragments. The recovery of rare earths from the lamp phosphors could be facilitated by taking advantage of the differences in resistance of the different lamp phosphors by chemical attack by inorganic ac- ids and bases.

关键词： balance problem fluorescence lamps lamp phosphors lanthanides rare-earth elements recycling urban mining

interpretation of tangential and radial pressure cells in and on sprayed concrete tunnel linings

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Underground Space 2021年第5期6卷 516-527页

作者： Benoit D.jones Chris R.i.Clayton inbye Engineering Limited Coventry CV12NPUK Department of Engineering University of SouthamptonSouthampton SO171BJUK

it is important to be able to measure stresses in tunnel linings to verify design assumptions and validate numerical *** sprayed concrete-lined tunnels,continuous monitoring of stresses from the time of spraying onwards is desirable,and this can only be achieved using pressure cells installed on and in the sprayed concrete *** there has been some success in using radial pressure cells between the ground and the lining,a method for obtaining reliable absolute values of stress from tangential pressure cells embedded in the sprayed concrete has not been *** paper describes numerical and experimental studies of the behavior of pressure cells for monitoring stresses in a sprayed concrete lining and describes an original methodology to achieve reliable *** particular,data from tangential pressure cells require careful interpretation,as they are sensitive to temperature,and this temperature sensitivity is found in parametric numerical analyses to vary as the stiffness of the concrete and its coefficient of thermal expansion evolve at early *** pressure cells are also sensitive to shrinkage strains in the concrete,and a methodology for removing this effect is *** the approach described in this paper,it is now possible to use pressure cells to measure absolute values of stresses in and on sprayed concrete tunnel linings from early age into the *** example of radial and tangential pressure cells installed in the Heathrow Terminal 4 concourse tunnel is used to illustrate the methodology.

关键词： Lining stresses Sprayed concrete Shotcrete Monitoring pressure cells

Asymptotic and numerical study of a surface breaking crack subject to a transient thermal loading

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Acta Mechanica Sinica 2006年第1期22卷 22-27页

作者： A.B. Movchan i.S. jones ljmu.ac.uk Department of Mathematical SciencesUniversity of Liverpoo UK L69 3BX School of EngineeringJames parsons BuildingJohn Moores UniversityByrom St.Liverpool UK. L3 3AF E-mail: i.s.jones

An asymptotic algorithm is applied to the problem of a finite, thermo-elastic solid containing a surface breaking crack, when the exterior surface is subjected to oscillatory thermal loading. This algorithm involves the study of a model problem. An analytical and numerical study of this model problem of a thermo-elastic half space containing a surface breaking crack and subjected to oscillatory thermal loading is presented. The crack surface is traction free. in particular, the amplitude of the stress intensity factor at the crack vertex is found as a function of the crack depth and the frequency of thermal oscillation.

关键词： Thermo-elasticity Surface breaking crack Wiener-Hopf solution Weight function method

An analysis of the size and direction of the association between mental toughness and Olympic distance personal best triathlon times

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Journal of Sport and Health Science 2019年第1期8卷 71-76页

作者： Martin i.jones John K.parker Sport and Health Science College of Life and Environmental Sciences University of Exeter School of Sport and Exercise Science University of Gloucestershire

Background: Athletes, coaches, sport psychology practitioners, and researchers suggest that mental toughness represents an important construct that is associated with athletic performance. Unfortunately, the absence of real-world performance as a dependent variable has limited our ability to substantiate this claim. The concern of a lack of ecologically valid measures of sports performance might be addressed by examining the relationship between mental toughness and sports performance using a standardized measure of personal best(pB) triathlon time and a validated unidimensional measure of mental ***: Three hundred and sixteen triathletes completed the 8-item mental toughness index(MTi), reported their age, and provided a pB Olympic distance triathlon time and the total number of triathlons they had completed to date. Given that males are typically quicker than females, a standardized time was calculated by dividing the pB by the current Olympic record for gender; we also hypothesized that more experienced triathletes would report quicker pB times because of greater frequency and duration of training. Once we had controlled for gender and experience,we predicted that mental toughness would be negatively associated with triathlon time and the size of the relationship would be of a moderate ***: Results revealed small-to moderate-sized negative relationships between both completed number of triathlons and mental toughness with standardized pB ***: The hierarchical regression analysis showed that mental toughness provided a unique contribution to the variability in standardized Olympic triathlon pB after controlling for the total number of triathlons completed.

关键词： Endurance sport Factorial validity Mental toughness Olympic distance triathlon performance personal best times

Oxidative damages to DNA by indoor pM10s: Their relationships with trace element compositions

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progress in Natural Science:Materials international 2005年第8期15卷 694-699页

作者： T. p. jones,L. MEROLLA School of Earth Ocean and planetary Sciences Cardiff University Cardiff CF10 3YE UK School of Biosciences Cardiff University Cardiff CF10 3US UK

plasmid DNA assay and iCp-MS analysis were conducted in order to investigate the bioreactivity of inhalable particles （pM_ 10） and the relationship between bioreactivity and trace element compositions of pM_ 10 in Beijing air. A total of four pM_ 10 samples were carefully selected to represent the indoor and corresponding outdoor environments: one from urban smoker's home, two from non-smoker's homes, and the other from the outdoor. in general, the oxidative damage by indoor pM_ 10 was slightly higher than that of outdoor. Among the four sets of samples, the pM_ 10 from the smoker's home had a lowest TD50 （toxic dose of pM_ 10 causing 50% DNA to be damaged）, being 100 μg·mL -1, suggesting the highest bioreactivity. The heavy metals are believed to be the main reason for oxidative damage to plasmid DNA. The iCp-MS analysis combined with the DNA assay showed that the water-soluble zinc levels had better relationship with TD50 values than other elements, implying that water-soluble zinc might play an important role in the damage of DNA. it is concluded that the pM_ 10 in smoker's home had the highest level of water-soluble zinc as well as the lowest TD50 （highest bioreactivity）. iron is considered to be one of the most bioreactive elements, but it will cause little damage to plasmid DNA, probably because iron is mainly in water-insoluble state in Beijing pM_ 10.

关键词： plasmid DNA assay oxidative capacity trace element indoor air pM_ 10.

Development of endemicity and conservation importance indices for tropical forests and the floral diversity assessment of *** in Benguet,philippines

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Journal of Mountain Science 2024年第3期21卷 786-804页

作者： Johndale Rein T.BULLONG Jim p.SiLVERiO Joanna i.ALAFAG Maricel A.GURON jones T.NApALDET Department of Environmental Science Benguet State UniversityLa Trinidad 2601Philippines Department of Biology Benguet State UniversityLa Trinidad 2601Philippines

The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally ***,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary *** shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the *** study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the *** indices were applied to ***,a remnant primary mossy forest in Buguias,Benguet,philippines,that resulted to endemicity index of 81.07 and conservation importance index of *** these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower ***,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical ***,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in *** are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate *** are important baseline information for conservation plans and monitoring of tropical mossy forests.

关键词： Endemicity index Conservation importance index Cordillera Central Range Floristic element Jaccard index of Similarity

Dim artificial light at night reduces the cellular immune response of the black field cricket, Teleogryllus commodus

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insect Science 2020年第3期27卷 571-582页

作者： Joanna Durrant Mark p.Green Theresa M.jones The School of BioSciences Faculty of ScienceUniversity of MelbourneVictoria3010Australia

A functioning immune system is crucial for protection against disease and illness,yet increasing evidence suggests that species living in urban areas could be suffering from immune suppression,due to the presence of artificial light at night(ALAN).This study examined the effects of ecologically relevant levels of ALAN on three key measures of immune function(haemocyte concentration,lytic activity,and phenoloxidase activity)using a model invertebrate species,the Australian black field cricket,Teleogryllus *** reared crickets under an ecologically relevant daily light‐cycle consisting of 12 hr bright daylight(2600 lx)followed by either 12 h darkness(0 lx)or dim environmentally relevant ALAN(1,10,100 lx),and then assessed immune function at multiple time points throughout adult life using haemolymph *** found that the presence of ALAN had a clear negative effect on haemocytes,while the effects on lytic activity and phenoloxidase activity were more complex or largely unaffected by ***,the effects of lifelong exposure to ALAN of 1 lx were comparable to those of 10 and 100 *** data suggest that the effects of ALAN could be large and widespread,and such reductions in the core immune response of individuals will likely have greater consequences for fitness and survival under more malign conditions,such as those of the natural environment.

关键词： circadian rhythm ecophysiology immune function immunomodulation invertebrate light pollution melatonin urbanization

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Acta Mechanica Sinica 2010年第4期26卷 567-572页

作者： D.J.Colquitt A.B.Movchan i.S.jones W.Daniels Department of Mathematical Sciences University of Liverpool School of Engineering John Moores University Serco Assurance Walton House 404 The QuadrantBirchwood ParkRisleyWarringtonCheshireWA3 6GAUK

The paper presents a computational model for elastic waves in a structured weld adjacent to the free surface of an elastic solid. The main emphasis is on the interaction of waves with the micro-structure of the weld. Effects of localisation and channeling of waves are addressed. A model of a grain structure within the weld is also considered.

关键词： Macro-structured welds Waves in stratified media Dispersion Localisation