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Arsenic and sulfur nanoparticle synthesis mimicking environmental conditions of submarine shallow-water hydrothermal vents

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Journal of Environmental Sciences 2022年第1期34卷 301-312页

作者： Vicente Durán-Toro Kurosch rezwan Solveig I.Bühring Michael Maas MArUM–Center for Marine Environmental Sciences University of BremenBremen 28359Germany Advanced Ceramics University of BremenBremen 28359Germany MAPEX-Center for Materials and Processes University of BremenBremen 28359Germany

Arsenic and sulfur mineralization is a natural phenomenon occurring in hydrothermal systems where parameters like temperature and organic matter(om)can influence the mobilization of the toxic metalloid in marine *** the present study we analyze the influence of temperature and om(particularly sulfur-containing additives)on As and S precipitation based on the recent discovery of As-rich nanoparticles in the hydrothermal system near the coast of the Greek island *** this end,we experimentally recreate the formation of amorphous colloidal particles rich in As and S via acidification(pH 3–4)of aqueous precursors at various *** higher temperatures,we observe the formation of monodisperse particles within the first 24 h of the experiment,generating colloidal particles with diameters close to 160 *** S:As ratio and particle size of the synthetized particles closely correlates with values for As_(x)S_(y)particles detected in the hydrothermal system off ***,organic sulfur containing additives(cysteine and glutathione,GSH)are a key factor in the process of nucleation and growth of amorphous colloidal As_(x)S_(y)particles and,together with the temperature gradient present in shallow hydrothermal vents,dictate the stabilization of As-bearing nanomaterials in the *** on these findings,we present a simple model that summarizes our new insights into the formation and mobility of colloidal As in aquatic *** this context,amorphous As_(x)S_(y)particles can present harmful effects to micro-and macro-biota not foreseen in bulk As material.

关键词： Biomineralization Milos Hydrothermal vent Arsenic Sulfur nanoparticles Ecotoxicology

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阿里安运载火箭第一、二级贮箱液位测量用的超声液位计

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导弹与航天运载技术(中英文) 1982年第6期 22-40页

作者： J-C.Demarais A.Děom 王晋桦

火箭飞行期间,对双组元液体火箭发动机推进剂贮箱的液位测量是一个重要参数,尤其是在为了确定瞬间推进剂混合比而随时对它进行控制时更为重要。可达此目标的手段之一是采用超声方法。这种方法在于测量由位于贮箱底部的探头发出并从液体... 详细信息

火箭飞行期间,对双组元液体火箭发动机推进剂贮箱的液位测量是一个重要参数,尤其是在为了确定瞬间推进剂混合比而随时对它进行控制时更为重要。可达此目标的手段之一是采用超声方法。这种方法在于测量由位于贮箱底部的探头发出并从液体表面反射回来的超声波的传播时间。法国航空空间研究院验证了在偏二甲肼（UDMH）和四氧化二氮（n2O4）中最大液位高度三米范围内这种测量方法的可行性。法国空间研究中心决定将此技术用于阿里安运载火箭第一、二级贮箱的液位测量。采用法国克鲁泽公司研制的飞行型液位测量装置,从实验室实验和级鉴定性热试期间所获得的试验结果验证了这种测量方法的有效性,达到的精度也满足技术要求。

关键词：反射器液位高度超声液位计推进剂贮箱液位测量

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Conditioning of a Calcaric Soil with Biosolid and Compost Under Laboratory Conditions: Exploration of Soil Property Evolution

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Pedosphere 2019年第2期29卷 266-272页

作者： José Antonio GALán-PérEZ Aránzazu PE?A Andalusian Institute for Earth Sciences Spanish National Research Council-University of Granada (CSIC-UGR)

Dear Editor,Conditioning of soils of low organic carbon(OC)is essential to establish optimal fertility conditions for the growth and development of future crops.A usual practice is the substrates of various origins,among which cheap wastes from agricultural or urban residues with high organic matter(om)content have been gaining popularity in the last *** increase in soil om is considered a desirable trait in agriculture because of its benefits.

关键词： Exploration Conditioning Laboratory

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Ethanol mediated As(Ⅲ) adsorption onto Zn-loaded pinecone biochar：Experimental investigation,modeling,and optimization using hybrid artificial neural network-genetic algorithm approach

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Journal of Environmental Sciences 2017年第4期29卷 114-125页

作者： Mohd.Zafar n.Van Vinh Shishir Kumar Behera Hung-Suck Park Center for Clean Technology and resource recycling University of Ulsan Ulsan 680749 South Korea Department of Applied Biotechnology Sur College of Applied Sciences Sur 411 Al Shariya Sultanate of Oman Department of Civil and Environmental Engineering University of Ulsan Ulsan 680749 South Korea Chemical Engineering Department GMR Institute of Technology Rajam 532127 Srikakulam Dist. India

Organic matters（oms） and their oxidization products often influence the fate and transport of heavy metals in the subsurface aqueous systems through interaction with the mineral surfaces. This study investigates the ethanol（EtO H）-mediated As（Ⅲ） adsorption onto Zn-loaded pinecone（PC） biochar through batch experiments conducted under Box–Behnken design. The effect of EtO H on As（Ⅲ） adsorption mechanism was quantitatively elucidated by fitting the experimental data using artificial neural network and quadratic modeling approaches. The quadratic model could describe the limiting nature of EtO H and pH on As（Ⅲ） adsorption,whereas neural network revealed the stronger influence of Et OH（64.5%） followed by pH（20.75%）and As（Ⅲ） concentration（14.75%） on the adsorption phenomena. Besides, the interaction among process variables indicated that Et OH enhances As（Ⅲ） adsorption over a pH range of2 to 7, possibly due to facilitation of ligand–metal（Zn） binding complexation ***, hybrid response surface model–genetic algorithm（rSM–GA） approach predicted a better optimal solution than rSM, i.e., the adsorptive removal of As（Ⅲ）（10.47 μg/g） is facilitated at 30.22 mg C/L of Et OH with initial As（Ⅲ） concentration of 196.77 μg/L at pH 5.8. The implication of this investigation might help in understanding the application of biochar for removal of various As（Ⅲ） species in the presence of om.

关键词： As(Ⅲ) removal Competitive adsorption Ethanol Box–Behnken design Artificial neural network Hybrid rSM–GA optimization

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Dislocation ordering and texture strengthening of naturally aged Al-Cu-Mg alloy

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Journal of Materials Science & Technology 2022年第23期118卷 1-14页

作者： F.Liu Z.Y.Liu G.Y.He L.n.Ou School of Materials Science and Engineering Central South UniversityChangsha 410083China Key Laboratory of nonferrous Metal Materials Science and Engineering Ministry of EducationCentral South UniversityChangsha 410083China national Key Laboratory of Science and Technology on High-Strength Structural Materials Central South UniversityChangsha 410083China

Stability of grain structure,dislocation ordering and strengthening mechanisms of the naturally aged AlCu-Mg alloy after solution treatment are investigated by using optical microscope(om),scanning electron microscope(SEM),electron back-scattered diffraction(EBSD),X-ray diffraction(XrD) and transmission electron microscope(TEM).results show that {100},{100},{110} and {110}slip systems can be activated after solution treatment,which can promote the formation of {110}Goss *** combination effect of T-Al_(20)Cu_(2) Mn_(3) phase and Goss-oriented grains with large Taylor factor makes the solution-treated alloys display excellent stability of grain *** enhanced yield strength of the alloy is ascribed to grain-refine strengthening,dispersed particles strengthening,dislocation strengthening and texture *** coarsening of the second phase is responsible for softening of the alloy after annealing at 400 ℃+solution treatment at 475 ℃.

关键词： Al-Cu-Mg alloy Dislocation ordering Goss texture Grain structure stability Texture strengthening

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Assessing adaptability and response of vegetation to glacier recession in the afro-alpine moorland terrestrial ecosystem of rwenzori Mountains

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Journal of Mountain Science 2016年第9期13卷 1584-1597页

作者： Tonny J.OYAnA Bob r.nAKILEZA Spatial Analytics and Informatics Core Department of Preventive Medicine The University of Tennessee Health Science Center Mountain resource Centre Department of Geography Geo-informatics and Climate Sciences Makerere University

The objective of this study was to explore vegetation adaptability in a changing afro-alpine moorland terrestrial ecosystem on Mt. rwenzori and to determine whether there were any links with response of vegetation to glacier recession. We analyzed the composition and distribution of plant species in relation to soils, geom.rphic processes, and landscape positions in the Alpine zone. To accomplish this objective, archival data sources and published reports for this ecosystem were reviewed. A field trip was conducted in 2010 to study in detail seven vegetation sampling plots that were systematically selected using GIS maps and a nested-quadrat sampling design framework along an altitudinal gradient in the lower and upper alpine zones. Using these sampling plots, 105 vegetation and 13 soil samples were assessed in the alpine zone. Soil samples were taken for laboratory testing and analysis. The results show statistically significant differences in pH, om, n, P, Ca, Mg, and K pools between soils samples drawn from the lower and upper alpine sites （p 〈 0.0033）. Furthermore, we observed a significant vegetation formation with numerous structural forms, but there was a limited diversity of speeies. The most significant forms included Alchemilla carpets, Bogs, Dendrosenecio woodland, and Scree slopes. The lower alpine area （3500-3900 masl） had a more diverse plant species than other areas, especially Alchemilla argyrophylla and Dendrosenecio adnivalis species that were evident due to well-drained deeper soils. The Alchemilla subnivalis were evident at a higher altitude of above 4000 mask Shifts in the Astareeeae （e.g. Senecio species） were particularly prominent even on recently deglaciated areas. The spatial variations of species distribution, structure, and composition suggest there are serious implications in terms of ecosystem adaptability, resilience, and stability that require further evaluation.

关键词： Alpine Plant species Species abundance Tropical afro-alpine ecosystems Afro-alpinemoorland

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Synthesis of crystalline perovskite-structured SrTiO_3 nanoparticles using an alkali hydrothermal process

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 109-115页

作者： U.K.n.Din T.H.T.Aziz M.M.Salleh A.A.Umar Institute of Microengineering and nanoelectronics (IMEn) Universiti Kebangsaan Malaysia

We report an experimental route for synthesizing perovskite-structured strontium titanate （SrTiO3） nanocubes using an alkali hydrothermal process at low temperatures without further heating. Furthermore, we studied the influence of heating time （at 180℃） on the crystallinity, morphology, and perovskite phase formation of SrTiO3. The SrTiO3 powder, which is formed via nanocube agglom.ration, transforms into cubic particles with a particle size of 120--150 nm after 6 h of hydrothermal sintering. The crystallinity and percentage of the perovskite phase in the product increased with heating time. The cubic particles contained 31.24at% anatase TiO2 that originated fi＇om the precursor. By varying the weight ratio of anatase TiO2 used to react with the strontium salt precursor, we reduced the anatase-TiO2 content to 18.8at%. However, the average particle size increased when the anatase-TiO2 content decreased.

关键词： strontium titanate nanoparticles anatase hydrothermal synthesis

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A cross-sectional study on coronary artery disease diagnosis in patients with peripheral artery disease

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Journal of Interventional Medicine 2022年第4期5卷 184-189页

作者： Jai Bharat Bhalke Shirish Hiremath C.n.Makhale om Multispeciality Hospital OmergaMaharashtraIndia ruby Hall Clinic PuneIndia

Purpose:Compared with healthy individuals,patients with peripheral artery disease(PAD)generally have a very high risk of subclinical Coronary artery disease(CAD)and cardiovascular *** determine the correlation between CAD in PAD patients,thereby promoting the lifetime of PAD patients and reducing the serious impacts of ***:This clinical-based cross-sectional study com.rised 100 consecutive patients in India from 2014 to *** this research,PAD patients were screened for CAD by treadmill stress test and cardiac colour Doppler *** addition,this study performed coronary angiography followed by peripheral angiography for patients who could not perform the treadmill ***:With the statistical results,the study observed a high prevalence of CAD in PAD patients that can be detected only with ***,30.93%of asymptomatic CAD prevalence was observed in PAD *** study strengthens the need for coronary angiography in all symptomatic lower limb PAD cases to detect early CAD,particularly in patients with diabetes and ***:There exists a strong correlation between PAD and ***,precise diagnosis followed by supervision of PAD patients is significant for avoiding local progression of cardiovascular risk.

关键词： Peripheral artery disease Coronary artery disease Angiography Cardiovascular risk ABI index

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Square-root parametrization of dark energy in f(Q)cosmology

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Communications in Theoretical Physics 2023年第12期75卷 105-114页

作者： M Koussour n Myrzakulov Alnadhief H A Alfedeel E I Hassan D Sofuoğlu Safa M Mirgani Quantum Physics and Magnetism Team LPMCFaculty of Science Ben M'sikCasablanca Hassan II University L.n.Gumilyov Eurasian national University ratbay Myrzakulov Eurasian International Centre for Theoretical Physics Department of Mathematics and Statistics Imam Mohammad Ibn Saud Islamic University(IMSIU) Department of Physics Faculty of ScienceUniversity of Khartoum Centre for Space research North-West University Department of Physics Istanbul University Vezneciler 34134

This paper is a parametrization of the equation of state(Eo S)parameter of dark energy(DE),which is parameterized using square-root(Sr)form i.e.ω_(Sr)=ω_(0)+ω_(1)z/√z^(2)+1,where ω_(0)and ω_(1) are free *** parametrization is examined in the context of the recently suggested f(Q)gravity theory as an alternative to general relativity(Gr),in which gravitational effects are attributed to the non-metricity scalar Q with the functional form f(Q)=Q+αQ^(n),whereαand n are arbitrary *** derive observational constraints on model parameters using the Hubble dataset with 31 data points and the Supernovae(Sne)dataset from the Pantheon samples compilation dataset with 1048 data *** the current model,the evolution of the deceleration parameter,density parameter,EoS for DE,and om(z)diagnostic have all been *** has been shown that the deceleration parameter favors the current accelerated expansion *** has also been shown that the EoS parameter for DE has a quintessence nature at this time.

关键词： cosmology dark energy f(Q)gravity EoS parameter

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Characterization of the negative carbon isotope shift in segment C2,its global implications as a harbinger of OAEla

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Science China Earth Sciences 2017年第1期60卷 30-43页

作者： Jander SOCOrrO Florentin J-M. r. MAUrrASSE Yosmel SAnCHEZ-HErnAnDEZ Department Earth and Environment Florida International University 11200 SW 8 Street Miami FL 33199 USA

Lower Cretaceous C-isotope records show intermittent negative/positive spikes, and consistent patterns of coevalchemostratigraphic curves thus document shifts that signal simultaneous responses of temporal changes in the global carbon reservoir. The standard pattern registered by the δ13Corg and δ13Ccarb in Lower Aptian sediments includes distinct isotope segments C1 to C8 （Menegatti et al., 1998）. In the E1 Pui section, Organy Basin, Spain, C-isotope segment C2 is the longest interval preceding segments C3-C6 associated with oceanic anoxic event la （OAE la）, and reveals a distinct negative shift of-1.8‰ to -2.23‰ defining the C-isotope pattern within that interval. Total inorganic carbon （TIC）, total organic carbon （TOC）, δ13Corg, microfacies, n-alkanes show no difference before, during, or after the negative inflection. The biom.rkers indicate that organic matter （om） mainly originates from algal/microbial sources because short-chain length homologues （〈 nCtg） dominate, nC2o through nC25 indicate some contribution from aquatic vegetation, but little from higher plants （〉nC20, as also suggested by the terrestrial/aquatic ratio ofn-alkanes or （TAr） = [（nf27＋nf29＋nC31）/（nC15＋nCt7＋rlCt9）] （averages 0.085）. We suggest that conjoint pulses of contemporaneous LIPs （Ontong Java） and massive explosive volcanism in northeast Asia, the Songliao Basin （SB-V）, best conform to plausible causes of the negative intra-C2 carbon isotopic excursion （CIE） at that time. Because of its apparent common occurrence the intra-C2 inflection could be a useful marker harbinger to the more pronounced CIE C3, the hallmark of OAE 1 a.

关键词： Oceanic Anoxic Event la (OAEla) Aptian Organy Basin Chemostratigraphy Pyrenees

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