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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

Severe acute pancreatitis： pathogenesis, diagnosis and surgical management

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Hepatobiliary & Pancreatic Diseases International 2017年第2期16卷 155-159页

作者： Mark Portelli Christopher david jones Department of General Surgery University Hospital Ayr Ayr KA6 6DX UK

BACKGROUND： Severe acute pancreatitis is a subtype of acute pancreatitis, associated with multiple organ failure and systemic inflammatory response syndrome. In this qualitative review we looked at the principles of pathogenesis, classification and surgical management of severe acute pancreatitis. We also looked at the current shift in paradigm in the management of severe acute pancreatitis since the guideline developed by the British Society of *** SOURCES： Studies published between 1st January 1991 and 31st December 2015 were identified with Pub Med, MEDLINE, EMBASE and Google Scholar online search engines using the following Medical Subject Headings： “acute pancreatitis, necrosis, mortality, pathogenesis, incidence” and the terms “open necrosectomy and minimally invasive necrosectomy”.the National Institute of Clinical Excellence（NICE） Guidelines were also included in our study. Inclusion criteria for our clinical review included established guidelines, randomized controlled trials and non-randomized controlled trials with a follow-up duration of more than 6 ***： the incidence of severe acute pancreatitis within the UK is significantly rising and pathogenetic theories are still controversial. In developed countries, the most common cause is biliary calculi. the British Society of Gastroenterology,acknowledges the Revised Atlanta criteria for prediction of severity. A newer Determinant-based system has been *** principle of surgical management of acute necrotizing pancreatitis requires intensive care management, identifying infection and if indicated, debridement of any infected necrotic area. the current procedures opted for include standard surgical open necrosectomy, endoscopic necrosectomy and minimally invasive necrosectomy. the current paradigm is shifting towards a step-up ***： Severe acute pancreatitis is still a subject of grey areas in its surgical management even though new studies have been recorde

关键词： severe acute pancreatitis acute pancreatitis necrosis mortality pathogenesis incidence open necrosectomy and minimally invasive necrosectomy

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

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： david A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

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

Field Phenomics:Will It Enable Crop Improvement?

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Plant Phenomics 2021年第1期3卷 310-325页

作者： david M.Deery Hamlyn G.jones CSIRO Agriculture and Food CanberraACTAustralia Division of Plant Sciences University of DundeeUK School of Agriculture and Environment University of Western AustraliaAustralia

Field phenomics has been identified as a promising enabling technology to assist plant breeders with the development of improved cultivars for ***,despite much investment,there are few examples demonstrating the application of phenomics within a plant breeding *** review recent progress in field phenomics and highlight the importance of targeting breeders’needs,rather than perceived technology needs,through developing and enhancing partnerships between phenomics researchers and plant breeders.

关键词： breeding cultivar Crop

Mapping informal settlement indicators using object-oriented analysis in the Middle East

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International Journal of Digital Earth 2019年第7期12卷 802-824页

作者： Ahmad Fallatah Simon jones david Mitchell Divyani Kohli School of Science RMIT UniversityMelbourneAustralia Faculty for Geo-Information Science and Earth Observation(ItC) University of TwenteEnschedeThe Netherlands

Mapping informal settlements is crucial for resource and utility management and *** 2003,the UN-Habitat developed a process for mapping and monitoring urban inequality to support reporting against the sustainable development goals(SDGs).Informal settlement indicators are used as a framework to carry out image analysis,and include vegetation extent,lacunarity of housing structures/vacant land,road segment type and materials,texture measures of built-up areas,roofing extent of built-up areas and dwelling *** image analysis(OBIA)methods are recommended to identify informal *** paper documents the application of OBIA to map informal settlements,drawing on the ontology of Kohli et al.(2012)and the indicators of Owen and Wong(2013)for a Middle Eastern *** informal settlements with different land use histories were selected to represent old and new informal settlements in the city of Jeddah,Saudi *** extent was the most successful indicator detected,with 100% producer accuracy and over 84% user accuracy,followed by the road network,with 84% producer and user accuracies in older informal settlements and 73% producer accuracy and 96% user accuracy across all case *** of housing structures/vacant land was detected well in informal *** texture measure indicator was detected using GLCM_(Ent)(R)with low producer accuracy across all case *** roofing extent of the built-up area is detected with better producer and user accuracies than texture *** dwellings size indicator generally failed to distinguish formal from informal *** and formal were distinguished with an overall accuracy of 83%.this research concludes that OBIA is a useful method to map informal settlement indicators in Middle Eastern ***,a generic ruleset for mapping informal settlements remains elusive,and each indicator requires significant localised‘tuning’.

关键词： Informal settlement objectbased image analysis(OBIA) sustainable development goals informal indicators high spatial resolution imagery Middle Eastern cities

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

Combining innovative science and policy to improve air quality in cities with refining and chemicals manufacturing： the case study of Houston, texas, USA

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 293-304页

作者： david t. Allen University of texas Austin Department of Chemical Engineering and Center for Energy and Environmental Resources Austin TX 78759 USA

In Houston, a combination of urban emissions from a city of 4 million people, coupled with emissions from extensive petroleum refining and chemical manufacturing, leads to conditions for photochemistry that are unique in the United States, and historically, the city had experienced some of the highest ozone concentrations recorded in the United States. Large air quality field studies （the texas Air Quality Studies or texAQS I and II） were conducted to determine root causes of the high ozone concentrations. Hundreds of air quality investigators, from around the world, deployed instruments on aircraft, on ships, and at fixed ground sites to make extensive air quality measurements; detailed photochemical modeling was used to interpret and assess the implications of the measurements. the texas Air Quality Studies revealed that both continuous and episodic emissions of light alkenes, which came to be called highly reactive volatile organic compounds, played a critical role in the formation of ozone and other photochemical oxidants in the region. Under- standing and quantifying the role of these emissions in regional air quality required innovations in characterizing emissions and in photochemical modeling. Reducing emissions required innovative policy approaches. these coupled scientific and policy innovations are described, and the result, substantially cleaner air for Houston, is documented. the lessons learned from the Houston air quality experience are relevant to cities with similar population and industrial profiles around the world.

关键词： ozone air quality highly reactive volatile organic compounds Houston