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Validation of basaltic glass adsorption capabilities from geothermal arsenic in a basaltic aquifer: A case study from Bjarnarflag power station,Iceland

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Geoscience Frontiers 2019年第5期10卷 1743-1753页

作者： K.C. Weaver M.A. Hoque s.M. Amin s.H. markússon A.P. Butler Department of Civil and Environmental Engineering Imperial College LondonLondonSW7 2BUUnited Kingdom school of Geography Environment and Earth SciencesVictoria University of WellingtonWellingtonNew Zealand school of Earth and Environmental sciences University of PortsmouthPortsmouth PO1 3QLUnited Kingdom Gas sustainability Technology Group Research and TechnologyProject Delivery and TechnologyPetronasMalaysia Landsvirkjun Háaleitisbraut 68103 ReykjavíkIceland

Arsenic is a carcinogen known for its acute toxicity to *** waters are commonly high in arsenic,as shown at the Bjarnarflag Power Plant,Iceland (w224 mg/kg of solvent).Development of geothermal energy requires adequate disposal of arsenic-rich waters into groundwater/geothermal *** outcome of arsenic transport models that assess the effect of geothermal effluent on the environment and ecosystems may be influenced by the sensitivity of hydraulic ***,previous such studies in Iceland do not consider the sensitivity of hydraulic parameters and thereby the interpretations remain *** we used the Lake Myvatn basaltic aquifer system as a case study to identify the sensitive hydraulic parameters and assess their role in arsenic *** develop a one-dimensional reactive transport model (PHREEQC ver.2.),using geochemical data from Bjarnarflag,*** our model,arsenite (H3AsO3) was predicted to be the dominant species of inorganic arsenic in both groundwater and geothermal *** reduced arsenic concentration beloww5 mg/*** reduced the residual contamination below w0.4 mg/kg at 250 m along *** on our modelling,we found volumetric input to be the most sensitive parameter in the *** addition,the adsorption strength of basaltic glass was such that the physical hydrogeological parameters,namely: groundwater velocity and longitudinal dispersivity had little influence on the concentration profile.

关键词： Geothermal Groundwater Hydrogeochemistry Arsenic Modelling

sedentary Behavior Research Network members support new Canadian 24-Hour Movement Guideline recommendations

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Journal of sport and Health science 2020年第6期9卷 479-481页

作者： mark s.Tremblay scott Rollo Travis J.saunders Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaONK1H 8L1Canada Department of Pediatrics Faculty of MedicineUniversity of OttawaOttawaONK1H 8M5Canada Department of Health sciences Carleton UniversityOttawaONK1S 5B6Canada Department of Applied Human sciences University of Prince Edward IslandCharlottetownPEIC1A 4P3Canada

A new paradigm employing 24-h movement guidelines that combines recommendations for movement behaviors across the whole day(physical activities of all intensities,sedentary behaviors,and sleep)is gaining momentum around the globe,and several jurisdictions are developing and releasing evidence-informed public health guidelines embracing this approach.1,2 The sedentary Behavior Research Network(sBRN),the world’s largest network of researchers and health professionals focusing specifically on the health impact of sedentary behaviors,embraces this new paradigm and has worked to normalize the integration of sedentary behaviors into the movement-behavior paradigm.

关键词： movement den behavior

Coal bursts in the deep longwall mines of the United states

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International Journal of Coal science & Technology 2016年第1期3卷 1-9页

作者： Christopher mark U.s. Mine safety and Health Administration Pittsburgh PAUSA

Coal bursts involve the sudden, violent ejection of coal or rock into the mine workings. They are a particular hazard because they typically occur without warning. During the past 2 years three Us coal miners were killed in two coal bursts, following a 6-year period during which there were zero burst fatalities. This paper puts the Us experience in the context of worldwide research into coal bursts. It focuses on two major longwall mining coalfields which have struggled with bursts for decades. The Utah experience displays many of the ＂classic＂ burst characteristics, including deep cover, strong roof and floor rock, and a direct association between bursts and mining activity. In Colorado, the longwalls of the North Fork Valley （NFV） also work at great depth, but their roof and floor strengths are moderate, and most bursts have occurred during entry development or in headgates, bleeders, or other outby locations. The NFV bursts also are more likely to be associated with geologic structures and large magnitude seismic events. The paper provides a detailed case history to illustrate the experience in each of these coalfields. The paper closes with a brief discussion of how Us longwalls have managed the burst risk.

关键词： Underground mining Coal Burst Longwall strata control

The origin of uniaxial negative thermal expansion in layered perovskites

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npj Computational Materials 2017年第1期3卷 89-96页

作者： Chris Ablitt sarah Craddock mark s.senn Arash A.Mostofi Nicholas C.Bristowe Department of Materials Imperial College LondonLondon SW72AZUK Department of Chemistry University of OxfordSouth Parks RoadOxford OX13QRUK Department of Chemistry University of WarwickGibbet HillCoventry CV47ALUK Department of Physics Imperial College LondonLondon SW72AZUK school of Physical sciences University of KentCanterbury CT27NHUK

Why is it that ABO3 perovskites generally do not exhibit negative thermal expansion(NTE)over a wide temperature range,whereas layered perovskites of the same chemical family often do?It is generally accepted that there are two key ingredients that determine the extent of NTE:the presence of soft phonon modes that drive contraction(have negative Grüneisen parameters);and anisotropic elastic compliance that predisposes the material to the deformations required for NTE along a specific *** difference in thermal expansion properties is surprising since both ABO3 and layered perovskites often possess these ingredients in equal measure in their high-symmetry *** first principles calculations and symmetry analysis,we show that in layered perovskites there is a significant enhancement of elastic anisotropy due to symmetry breaking that results from the combined effect of layering and condensed rotations of oxygen *** feature,unique to layered perovskites of certain symmetry,is what allows uniaxial NTE to persist over a large temperature *** fundamental insight means that symmetry and the elastic tensor can be used as descriptors in high-throughput screening and to direct materials design.

关键词： perovskite layered symmetry

Hydrogen Hubs Arise in the United states

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Engineering 2024年第11期42卷 3-5页

作者： mark Peplow 不详

July 2024 saw the first"hydrogen hub"(H2Hub)officially launched in the United states[1].Centered in the state of California,the hub is one of a group of seven such H2-focused infrastructure projects across the country(Table 1)selected to share 7 billion UsD in funding allocated by the Biden-Harris Administration in October 2023[2].The aim for the investment is to accelerate the country’s production and use of H_(2)as a fuel and feedstock chemical;H_(2)combustion releases only water,and many believe that the gas could help to reduce climate-changing CO_(2)emissions by replacing fossil fuels in transportation,the chemicals industry,and other economic sectors.

关键词： release official funding

Nevanlinna theory of meromorphic functions on annuli

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science China Mathematics 2010年第3期53卷 547-554页

作者： LUND mark Department of Mathematics College of DuPage

In this survey paper, we discuss the recent development of Nevanlinna theory of meromorphic functions on annuli, which extends results in Nevanlinna theory in the complex plane or in a disk. In particular, we show that the approach taken on annuli is a unified treatment of functions meromorphic in the complex plane, a disk and an annulus. It allows one to obtain many results in the complex plane and in a disk as corollaries of our results in annuli.

关键词： Nevanlinna theory meromorphic function annulus

Compatibility of Beauveria bassiana with Neoseiulus barkeri for Control of Frankliniella occidentalis

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Journal of Integrative Agriculture 2015年第1期14卷 98-105页

作者： WU sheng-yong GAO Yu-lin XU Xue-nong mark s Goettel LEI Zhong-ren state Key Laboratory for Biology of Plant Diseases and Insect Pests I nstitute of Plant ProtectionChinese Academy of Agricultural Sciences Lethbridge Research Centre Agriculture and Agri-Food Canada

The entomopathogenic fungus Beauveria bassiana （Balsamo） Vuillemin and predatory mite Neoseiulus barked Hughes are effective biological control agents of Frankliniella occidentalis Pergande （Thysanoptera： Thripidae）, one of the most important pests of ornamentals and vegetables world-wide. Combined application of both may enhance control efficiency. The functional response for N. barked on the first instar larvae of western flower thrips which were infected by B. bassiana for 12 and 24 h in the laboratory （（25＋1）℃, （70＋5）% RH, L：D=16 h：8 h） was determined. The virulence of B. bassiana against the second instar and pupae of the thrips attacked by N. barked were also tested. The results showed that N. barked exhibited a Holling type II functional response on treated thrips. After having been treated with the fungus for 12 h and then offered to the predator, thrips were more vulnerable to be killed by N. barked. The second instar larvae and pupae of the thrips which had been attacked by predatory mites were markedly more susceptible to B. bassiana infection than normal thrips; the cumulative corrected mortality of B. bassiana of the second instar and pupae which were attacked by N. barked were 57 and 94%, respectively, compared to 35 and 80% in controls on the day 8. These findings highlight the potential use of B. bassiana in combination with N. barkeri to control F. occidentalis.

关键词： Beauveria bassiana Neoseiulus barkeri Frankfiniella occidentalis functional response virulence

Biosphere 2’s Lessons about Living on Earth and in space

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space(science & Technology) 2021年第1期2021卷 274-284页

作者： mark Nelson Institute of Ecotechnics(Us/UK) USA

Biosphere 2,the largest and most biodiverse closed ecological system facility yet created,has contributed vital lessons for living with our planetary biosphere and for long-term habitation in *** the space life support perspective,Biosphere 2 contrasted with previous BLss work by including areas based on Earth wilderness biomes in addition to its provision for human life support and by using a soil-based intensive agricultural system producing a complete human *** previous BLss system had included domestic farm *** human and domestic animal wastes were also recycled and returned to the crop *** 2 was important as a first step towards learning how to miniaturize natural ecosystems and develop technological support systems compatible with *** 2’s mostly successful operation for three years(1991-1994)changed thinking among space life support scientists and the public at large about the need for minibiospheres for long-term habitation in *** an Earth systems laboratory,Biosphere 2 was one of the first attempts to make ecology an experimental science at a scale relevant to planetary issues such as climate change,regenerative agriculture,nutrient and water recycling,loss of biodiversity,and understanding of the roles wilderness biomes play in the Earth’s *** 2 aroused controversy because of narrow definitions and expectations of how science is to be *** cooperation between engineers and ecologists and the requirement to design a technosphere that supported the life inside without harming it have enormous relevance to what is required in our global *** of bioregenerative life support systems for near-term space applications such as initial Moon and/or Mars bases,will be severely limited by high costs of transport to space and so will rely on lighter weight,hydroponic systems of growing plants which will focus first on water and air regeneration and gradually increase its production of fo

关键词： Earth Biosphere bases

Oxidative stress and male reproductive health

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Asian Journal of Andrology 2014年第1期16卷 31-38页

作者： Robert J Aitken Tegan B smith Matthew s Jobling mark A Baker Geoffry N De Iuliis Priority Research Centre in Reproductive science Discipline of Biological Sciences Faculty of Science and IT University of Newcastle Callaghan NSW 2308 Australia

One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high leve｜s of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair （BER） pathway, 8-oxoguanine glycosylase 1 （OGG1）. The latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins （APE1, XRCC1） needed to complete the repair process. It is the responsibility of the oocyte to continue the BER pathway prior to initiation of s-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

关键词： DNA damage oxidative stress oxoguanine glycosylase 1 oocyte spermatozoa