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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

Randomized controlled trials - mechanistic studies of testosterone and the cardiovascular system

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Asian Journal of Andrology 2018年第2期20卷 120-130页

作者： t Hugh jones Daniel M Kelly Robert Hague Centre for Diabetes and Endocrinology Barnsley Hospital NHS Foundation Trust Barnsley UK Academic Unit of Diabetes Endocrinology and Metabolism Department of Oncology and Metabolism University of Sheffield Medical School Sheffield UK biomedical Research Centre Sheffield Hallam University Sheffield UK

testosterone deficiency is common in men with cardiovascular disease （CVD）, and randomized placebo-controlled trials （RCts） have reported beneficial effects of testosterone therapy on exercise-induced cardiac ischemia in chronic stable angina, functional exercise capacity, maximum oxygen consumption during exercise （VO2m,x） and muscle strength in chronic heart failure （CHF）, shortening of the Q-t interval, and improvement of some cardiovascular risk factors. testosterone deficiency is associated with an adverse CV risk profile and mortality. Clinical and scientific studies have provided mechanistic evidence to support and explain the findings of the RCts. testosterone is a rapid-onset arterial vasodilator within the coronary circulation and other vascular beds including the pulmonary vasculature and can reduce the overall peripheral systemic vascular resistance. Evidence has demonstrated that testosterone mediates this effect on vascular reactivity through calcium channel blockade （L-calcium channel） and stimulates potassium channel opening by direct nongenomic mechanisms. testosterone also stimulates repolarization of cardiac myocytes by stimulating the ultra-rapid potassium channel-operated current. testosterone improves cardiac output, functional exercise capacity, VO2m=x and vagally mediated arterial baroreceptor cardiac reflex sensitivity in CHF, and other mechanisms. Independent of the benefit of testosterone on cardiac function, testosterone substitution may also increase skeletal muscle glucose metabolism and enhance muscular strength, both factors that could contribute to the improvement in functional exercise capacity may include improved glucose metabolism and muscle strength. testosterone improves metabolic CV risk factors including body composition, insulin resistance, and hypercholesterolemia by improving both glucose utilization and lipid metabolism by a combination of genomic and nongenomic actions of glucose uptake and utilization expression of the

关键词： cardiovascular testosterone testosterone replacement

the glassy solid as a statistical ensemble of crystalline microstates

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npj Computational Materials 2020年第1期6卷 1199-1204页

作者： Eric b.jones Vladan Stevanović Colorado School of Mines GoldenCO 80401USA National Renewable Energy Laboratory GoldenCO 80401USA

We present an alternative and,for the purpose of non-crystalline materials design,a more suitable description of covalent and ionic glassy solids as statistical ensembles of crystalline local minima on the potential energy *** by the concept of partially broken ergodicity,we analytically formulate the set of approximations under which the structural features of ergodic systems such as the radial distribution function(RDF)and powder X-ray diffraction(XRD)intensity can be rigorously expressed as statistical ensemble averages over different local *** is carried out by evaluating these ensemble averages for elemental Si and SiO_(2) over the local minima obtained through the first-principles random structure sampling that we performed using relatively small simulation cells,thereby restricting the sampling to a set of predominantly crystalline *** comparison with XRD and RDF from experiments(amorphous silicon)and molecular dynamics simulations(glassy SiO_(2))shows excellent agreement,thus supporting the ensemble picture of glasses and opening the door to fully predictive description without the need for experimental inputs.

关键词： ensemble crystalline glasses

Distribution and morpho-anatomical characterization of ’beket’(Coriaria japonica subsp. intermedia(Matsum) t.C. Huanh) in Cordillera Central Range, Northern Philippines

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Journal of Mountain Science 2020年第9期17卷 2136-2147页

作者： Maricel A.GURON jones t.NAPALDEt biology Department Benguet State UniversityBenguet 2601Philippines University of Philippines Los banos Laguna 4031Philippines

Coriaria,the only genus under family Coriariacea,receives a lot interest among botanist due to its controversial taxonomic treatment and unique phytochemistry that could be commercially *** populations of Coriaria japonica *** in Cordillera Central Range(CCR),Philippines had never been studied in *** the need for more information on this controversial genus,the study deemed it necessary to present the distribution and morpho-anatomical description of *** *** in CCR.A total of 123 populations were documented,found at an elevation range of 1334 to 2494 m asl and stretched between16°31’37.7"to 17°5’47.8"N and 120°39’40.3"to120°55’48"*** these populations showed a narrow linear pattern of distribution concentrated at the southern portion of *** plant is a shrub with simple leaves,collateral buds,raceme inflorescence,bisexual flowers with persistent perianth forming an accessory fruit after *** terms of anatomy,much are of the usual dicot characters such as dorsiventral leaf with stomata concentrated in the lower epidermis,eustele with pith in the stem andpresence of secondary growth both on old stem and old *** findings of the study include the123 populations,the larger leaf measurements,longer petals and larger fruits than the original description given by ***,the paracytic type of stomata and presence of pith in the primary roots of *** *** are interesting since these are common monocot characters while the plant is *** findings are additional information that could help clear the controversies on the genus *** importantly,our results could provide essential information for understanding the plant and for developing conservation strategies not just for this plant but also for the other related plants in the CCR biogeographical zone.

关键词： Coriaria japonica subsp.intermedia Cordillera Central Range Geographical distribution Paracytic type Pith in dicot root

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.

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

Ligand-mediated contaminant degradation by bare and carboxymethyl cellulose-coated bimetallic palladium-zero valent iron nanoparticles in high salinity environments

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Journal of Environmental Sciences 2019年第3期31卷 303-311页

作者： Xiaoming Ma Di He Adele M.jones t.David Waite taicheng An Institute of Environmental Health and Pollution Control Guangdong University of Technology Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control School of Environmental Science and Engineering Guangzhou University of Technology School of Civil and Environmental Engineering University of New South Wales

the application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study, the ability of bare and carboxymethyl cellulose(CMC)-coated bimetallic Pd-nZVI particles to degrade 33′44′-tetrachlorobiphenyl in high saline water(SW) is examined with particular attention given to the effects of ethylenediaminetetraacetic acid(EDtA) on the rate of degradation. EDtA enhances the reactivity of Pd-nZVI in SW, with evidence provided to link this to the removal of the passivating layer. Additionally, a conceptual model is proposed which provides a quantitative description of the removal of these iron oxide layers in the presence of EDtA. An optimum EDtA to bare Pd-nZVI molar ratio of 0.1 exists, with insufficient EDtA unable to remove the passivating layer whilst excess EDtA results in Fe loss and enhanced agglomeration due to magnetic attraction of the bare Fe(0) particles. In contrast, CMCcoating of Pd-nZVI assemblages actually impedes degradation, despite the coated particles displaying a smaller average size compared to uncoated particles, with even the presence of EDtA in this case not significantly improving degradation. the reduced reactivity in the presence of CMC is primarily attributed to the effect of CMC on the association of Pd with nZVI particles. In particular, the presence of CMC reduced the total amount of Pd incorporated with the stabilized particles compared to the non-stabilized ***, the presence of CMC results in less Pd present in its reactive zero-valent oxidation state.

关键词： bimetallic zero valent iron ligand-mediated depassivation polychlorinated biphenyls high salinity water

Numerical simulation of the effect of gold doping on the resistance to neutron irradiation of silicon diodes

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Journal of Semiconductors 2015年第1期36卷 47-51页

作者： K.bekhouche N.Sengouga b.K.jones Laboratory of Metallic and Semiconducting Materials (LMSM) Université de Biskra 07000 Biskra Algeria Department of Physics Lancaster University Lancaster LA5 9LX UK

We have carried out a numerical simulation of the effect of gold doping on the electrical characteristics of long silicon diodes exposed to neutron irradiation. the aim is to investigate the effect of gold on the hardness of the irradiated diodes. the reverse current voltage and capacitance voltage characteristics of doped and undoped diodes are calculated for different irradiation doses. the leakage current and the effective doping density are extracted from these two characteristics respectively. the hardness of the diodes is evaluated from the evolution of the leakage current and the effective doping density with irradiation doses. It was found that diodes doped with gold are less sensitive to irradiation than undoped ones. thus gold appears to stabilise the electrical properties on irradiation. the conduction mechanism is studied by the evolution of the current with temperature. the evaluated activation energy indicates that as the gold doping or irradiation dose increases, the current switches from the basic diffusion to the generation-recombination process, and that it can even become ohmic for very high gold densities or irradiation doses.

关键词： silicon diodes gold doping numerical simulation

Measuring vacuum polarization with high-power lasers

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High Power Laser Science and Engineering 2016年第1期4卷 29-40页

作者： b.King t.Heinzl Centre for Mathematical Sciences Plymouth University

When exposed to intense electromagnetic fields, the quantum vacuum is expected to exhibit properties of a polarizable medium akin to a weakly nonlinear dielectric material. Various schemes have been proposed to measure such vacuum polarization effects using a combination of high- power lasers. Motivated by several planned experiments, we provide an overview of experimental signatures that have been suggested to confirm this prediction of quantum electrodynamics of real photon–photon scattering.

关键词： Heisenberg–Euler photon–photon scattering vacuum birefringence vacuum polarization