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Arsenic and major cation hydrogeochemistry of the Central Victorian （Australia） surface waters

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Journal of environmental Sciences 2006年第1期18卷 184-192页

作者： Khawar SULTAN Kim dowling School of Science and engineering University of Ballarat Mount Helen University Drive Ballarat Victoria 3353 Australia

This paper reports on the major cations（Ca, Mg, Na and K） and arsenic（As） compositions of surface waters collected from major creeks, rivers and lakes in Central Victoria （Australia）. The surface waters were found to be neutral to alkaline （pH 6.7-9.4）, oxidised （average redox potential （eh） about 130 mV） and showed variable concentrations of dissolved ions （eC, about 51-4386 /μS/cm）. The concen- trations of dissolved major cations in surface waters were found to be in the order of Na〉〉Mg〉Ca〉K and in soils the contents of metals followed an order of abundance as： Ca〉Mg〉〉K〉Na. While Na was the least abundant in soils, it registered the highest dissolved cation in surface waters. Of the four major cations, the average concentration ofNa（98.7 mg/L） was attributed to the weathering of feldspars and atmospheric input. Relatively highly dissolved concentrations of Na and Mg compared with the world average values of rivers reflected the weathering of rock and soil minerals within the catchments. The As soil level is naturally high（linked to lithology） as reflected by high background soil values and mining operations are also considered to be a contributory factor. Under relatively alkaline-oxidative conditions low mobility of dissolved As （average about 7.9 μg/L） was observed in most of the surface waters with a few higher values（〉15 μg/L） around a sewage disposal site and mine railings. Arsenic in soils is slowly released into water under alkaline and/or lower eh conditions. The efficient sink of Fe, AI and Mn oxides acts as a barrier against the As release under near neutral-oxidising conditions. High As content （average about 28.3 mg/kg） in soils was found to be associated with Fe-hydroxides as revealed by XRD and SeM analysis. The dissolved As concentration was found to be below the recommended maximum levels for recreational water in all surface waters（lakes and rivers） in the study area. Catchment lithology exerted the fundamental control on surface water chemistr

关键词： surface water major cations arsenic soil Australia

Mechanical characterization of the role of defects in sintered FeCrAIY foams

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Acta Mechanica Sinica 2007年第4期23卷 383-398页

作者： M.Kepets A.P.dowling engineering Department Cambridge UniversityCambridge CB2 1PZUK

Open celled metal foams fabricated through metal sintering are a new class of material that offers novel mechanical and acoustic properties. Previously, polymer foams have been widely used as a means of absorbing acoustic energy. However, the structural applications of these foams are limited. The metal sintering approach offers a costeffective means for the mass-production of open-cell foams from a range of materials, including high-temperature steel alloys. In this first part of two-paper series, the mechanical properties of open-celled steel alloy （FeCrA1Y） foams were characterized under uniaxial compression and shear loading. Compared to predictions from established models, a significant knockdown in material properties was observed. This knockdown was attributed to the presence of defects throu- ghout the microstructure that result from the unique fabrication process. Further in situ tests were carried out in a SeM （scanning electronic microscope） in order to investigate the effects of defects on the properties of the foams. Typically, the onset of plastic yielding was observed to occur at defect locations within the microstructure. At lower relative densities, ligament bending dominates, with the deformation initializing at defects. At higher relative densities, an additional deformation mechanism associated with membrane elements was observed. In the follow-up of this paper, a finite element model will be constructed to quantify the effects of defects on the mechanical performance of the opencell foam.

关键词： Metal foam Defect Mechanical characterization SeM

Terrestrial Analogue Research to Support Human Performance on Mars:A Review and Bibliographic Analysis

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Space(Science & Technology) 2022年第1期2022卷 307-324页

作者： Andrew Terhorst Jason A.dowling CSIRO Data 61 HobartAustralia CSIRO Australian e-Health Research Centre BrisbaneAustralia

Terrestrial analogues can provide essential scientific information and technology validation to assist future crewed missions to the Martian *** paper analyses the recent literature since 2010 in this area,highlighting key topics,authors,and research *** reviews analogue locations,missions,the scientific impact from research *** findings indicate that permanent analogue sites enable reproducible science and objective comparison between studies.A standard,open registry of analogue facilities,and associated peer-reviewed research may lead to accelerated and better targeted analogue research.

关键词： surface. analogue analogues

NeCAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael K.e.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal eF-hand calcium-binding proteins 1–3(NeCAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one eF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NeCAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NeCAB2 interacts with predominantly striatal G-protein-coupled receptors, while NeCAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NeCAB proteins exhibit distinct subcellular localizations: NeCAB1 is found in the nucleus and cytosol, NeCAB2 resides in endosomes and the plasma membrane, and NeCAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NeCAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NeCAB proteins by controlling the availability of protein–protein interaction domains situated between the eF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium eF hand mitochondria nervous system signal transduction

Acoustic properties of sintered FeCrAlY foams with open cells (Ⅰ): Static flow resistance

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Science China(Technological Sciences) 2008年第11期51卷 1803-1811页

作者： M. KePeTS A. P. dowling Cambridge University engineering Department Cambirdge CB2 1PZ U.K.

Open celled metal foams fabricated through the route of metal sintering are a new class of material that offers novel mechanical and acoustic properties. The metal sintering approach offers a cost-effective means for the mass-production of open-cell foams from a range of materials, including high-temperature steel alloys. The mechanical properties of open-celled steel alloy (FeCrAlY) foams have been characterized in previous studies, with focus placed on the influence of processing defects on stiffness and strength. In this work, the low-Reynolds number fluid properties of FeCrAlY foams were investigated both theoretically and experimen- tally. Specifically, the static flow resistance of the sintered foams important for heat transfer, filtration and sound absorption was modeled based on a cylinder and a sphere arranged in a periodic lattice at general incidence to the flow. experimental measurements were subsequently carried out to validate theoretical predictions, with good agreement achieved.

关键词： metal foam static flow resistance modeling experiment

Search for a natural scientific measure of economy

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Frontiers of environmental Science & engineering 2011年第1期5卷 111-118页

作者： john e COULTeR Xiwangzhuang Shuangqing RdHaidianBeijing 100084China

Through human history,wealth has been measured in grain,gold,and,now,*** counterfeiting of coins and notes goes back a long way,it is only with electronic financial accounting in a global economy tainted by toxic loans and imaginary funds that there is an urgency to search for a realistic objective way to monitor and regulate what we are doing to our earth and *** schemes using analysis of utility functions,oil equivalents,entropy,energy,and other units have been tried and,while helping to understand some basic processes and flows,have always been swamped by the machinations of financiers and the attention big sums of money ***,the concept of exergy,pioneered in eastern europe in the 1950s,is being researched,developed,and applied,especially in China,driven by the desperation to measure the reality beyond the twin specters of global financial and environmental crises.A rough inventory of the matter in the biosphere at the coordinate details of an angstrom and an appreciation of how humans harness and manipulate electromagnetic forces can be enlightening as to what is and is not *** that understanding,any financial estimate and proposed stimulus packages or IMF reform will be wildly wrong and may even be headed in the wrong direction.

关键词： climate change financial crisis energy exergy environment

Modeling of the role of defects in sintered FeCrAlY foams

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Acta Mechanica Sinica 2007年第5期23卷 511-529页

作者： M.Kepets T.J.Lu A.P.dowling Cambridge University engineering Department Cambridge CB2 1PZUK MOe Key Laboratory of Strength and Vibration School of AerospaceXi'an Jiaotong UniversityXi'an 710049China

The metal sintering approach offers a costeffective means for the mass-production of open-cell foams from a range of materials, including high-temperature steel alloys, which offer novel mechanical and acoustic properties. In a separate experimental study, the mechanical properties of open-celled steel alloy （FeCrA1Y） foams have been characterized under uniaxial compression and shear loading. Compared to predictions from established models, a significant knockdown in material properties was observed. This knockdown was attributed to the presence of defects throughout the microstructure that result from the unique fabrication process. In the present paper, the microstructure of sintered FeCrA1Y foams was modeled by using a finite element （Fe） model. In particular, microstructural variations were introduced to a base lattice, and the effects on the strength and stiffness calculated. A range of defects identified under scanning electronic microscope （SeM） imaging were considered including broken ligaments, thickness variations, and pore blockages, which are the three primary imperfections observed in sintered foams. The corresponding levels of defect present in the material were subsequently input into the Fe model, with the resulting predictions correlating well with experimental data.

关键词： Metal foam Mechanical performance Defect Finite element SeM

Acoustic properties of sintered FeCrAlY foams with open cells (Ⅱ): Sound attenuation

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Science China(Technological Sciences) 2008年第11期51卷 1812-1837页

作者： M. KePeTS A. P. dowling2 Cambridge University engineering Department Cambirdge CB2 1PZ U.K.

Open-celled metal foams fabricated through metal sintering offers novel mechani- cal, thermal and acoustic properties. Previously, polymer foams were used as a means of absorbing acoustic energy. However, the structural applications of these foams are inherently limited. The metal sintering approach provides a cost-effective means for the mass-production of open-cell foams from a range of materials, in- cluding high-temperature steel alloys. The low Reynolds number fluid properties of sintered steel alloy (FeCrAlY) foams were investigated in a previous study. The static flow resistance of the foams was modeled based on a cylinder and a sphere arranged in a periodic lattice at general incidence to the flow, with the resulting predictions correlating well to measurements. The application of the flow resis- tance in an acoustic model is the primary focus of the present study. The predic- tions for the static flow resistance of the sintered foams are first used in a theo- retical model to determine the characteristic impedances, as well as the propaga- tion constants of the foams. Subsequently, the predicted acoustic performance of the foams is compared to experimental results. Finally, the design space for a simple acoustic absorber incorporating sintered foams is examined, with the ef- fects of absorber size, foam selection, and foam spacing explored.

关键词： metal foam sound absorption modeling experiment acoustic design

Recent Advancements in the Optimization Capacity Configuration and Coordination Operation Strategy of Wind-Solar Hybrid Storage System

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energy engineering 2025年第1期122卷 285-306页

作者： Hongliang Hao Caifeng Wen Feifei Xue HaoQiu Ning Yang Yuwen Zhang Chaoyu Wang edwin e.Nyakilla Department of New energy Storage Peking University Ordos Research Institute of EnergyOrdos017010China School of energy and Power engineering Inner Mongolia University of TechnologyHohhot010080China Key Laboratory of Wind energy and Solar energy Utilization Technology Inner Mongolia University of TechnologyHohhot010051China

Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy *** paper proposes a wind-solar hybrid energy storage system(HeSS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,***/Simulink was used for simulation *** optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 ***,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations *** proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.

关键词： electric-thermal hybrid storage modal decomposition multi-objective genetic algorithm capacity optimization allocation operation strategy