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Electrochemical reduction of Cr(Ⅵ)in the presence of sodium alginate and its application in water purification

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Journal of Envir.n.ental Sciences 2021年第3期33卷 304-312页

作者： bryan Butter Paola Santander Guadalupe del CPizarro Diego POyarzún Federico Tasca Julio Sánchez Facultad de Química y Biología Universidad de Santiago de ChileUSACHCasilla 40Correo 33SantiagoChile Departamento de Química Universidad Tecnológica MetropolitanaJ.P.Alessandri 1242SantiagoChile Laboratorio de nanotecnología Recursos Naturales y Sistemas ComplejosFacultad de Ciencias NaturalesUniversidad de AtacamaCopayapu 485CopiapóChile

Chromium(Cr)is used in many manufactur.n. processes,and its release into natural waters is a major envir.n.ental problem *** concentrations of Cr(Ⅵ)are toxic to human health and living organisms due to the carcinogenic and mutagenic nature of this *** work examined the conversion of Cr(Ⅵ)to Cr(Ⅲ)via electrochemical reduction using gold electrode in an acidic sodium alginate(SA)solution and subsequent removal of the produced Cr(Ⅲ)-SA by the polymer-enhanced ultrafiltration(PEUF)technique.A solution of SA in nitric acid was used both as an electrolytic medium dur.n. the voltammetric measurements and bulk electrolysis and as an extracting agent dur.n. the PEUF *** electroanalysis of Cr(Ⅵ)was performed by linear sweep voltammetry in the presence of acidic SA solution to study its voltammetric behavior as a function of the Cr(Ⅵ)concentration,pH,presence of Cr(Ⅲ),SA concentration and scan *** addition,the quantitative reduction of Cr(Ⅵ)to Cr(Ⅲ)was studied through the bulk electrolysis *** results showed efficient reduction with well-defined peaks at approximately 0.3 V ***/AgCl,using a gold working *** the pH increased,the reduction signal str.n.ly decreased until its *** optimum SA concentration was 10 mmol/L,and it was observed that the presence of Cr(Ⅲ)did not interfere in the Cr(Ⅵ)*** the quantitative reduction by bulk electrolysis in the presence of acidic SA solution,it was possible to reduce all Cr(Ⅵ)to Cr(Ⅲ)followed by its removal via PEUF.

关键词： Alginate solution Chromium Electroanalytical chemistry Ultrafiltration Water purification

Association of Congenital Heart Defects (CHD) with Factors related to Maternal Health and Pregnancy in newborns in Puerto rico

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Congenital Heart Disease 2024年第1期19卷 19-31页

作者： Yamixa Delgado Caliani Gaytan naydi Perez Eric Mir.n.a bryan Colón Morales Mónica Santos Biochemistry&Pharmacology Department San Juan Bautista School of MedicineCaguas00726Puerto Rico Hispanic Alliance for Clinical and Tr.n.lational research University of Puerto Rico Medical Sciences CampusSan Juan00936Puerto Rico Department of Internal Medicine University of Puerto Rico Medical Sciences CampusSan Juan00936Puerto Rico

Background:Given the pervasive issues of obesity and diabetes both in Puerto rico and the broader United States,there is a compelling need to investigate the intricate interplay among body mass index(BMI),pregesta-tional,and gestational maternal diabetes,and their potential impact on the occurr.n.e of congenital heart defects(CHD)dur.n. neonatal ***:Using the comprehensive System of Vigilance and Surveillance of Congenital Defects in Puerto rico,we conducted a focused analysis on neonates diagnosed with CHD between 2016 and *** assessment encompassed a r.n.e of variables,including maternal age,gestational age,BMI,pregestational diabetes,gestational diabetes,hypertension,history of abortion,and presence of ***:A cohort of 673 patients was included in our *** average maternal age was 26 years,within a r.n.e of 22 to 32 *** mean gestational age measured 39 weeks,with a median span of 38 to 39 *** the 673 patients,274(41%)mothers gave birth to neonates diagnosed with *** this group,22 cases were linked to pre-gestational diabetes,while 202 were not;20 instances were associated with gestational diabetes,compared to 200 without;and 148 cases exhibited an overweight or obese BMI,whereas 126 displayed a normal ***:We identiﬁed a statistically signiﬁcant correlation between pre-gestational diabetes mellitus and the occurr.n.e of ***,our analysis did not show a statistically signiﬁcant association between maternal BMI and the likelihood of *** results may aid in developing effective strategies to prevent and manage CHD in neonates.

关键词： Congenital heart defects(CHD) obesisty maternal health diabetes body mass index(BMI)

A private SUSY 4HDM with FCnC in the up-sector

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Chinese Physics C 2021年第2期45卷 326-340页

作者： M.A.Arroyo-Ureña Lor.n.o Díaz-Cruz bryan O.Larios-López M.A.Pérez de León Facultad de Estudios Superiores Cuautitlan-UnAM Cuautitlan Edo de MexMéxico Mesoamerican Center for Theoretical Physics UNACHChiapasMéxico CIFFU and Facultad de Ciencias Físico-Matemáticas Benemérita Universidad Autónoma de Puebla ApdoPostal 1364CP72000PueblaPueMéxico Departamento de Gravitación y Altas Energías Facultad de Ciencias Universidad Nacional Autónoma de Honduras Ciudad UniversitariaTegucigalpa MDCHonduras

We present a SUSY model with four Higgs doublets of the"private type,"in which all fermion types(up,down,and charged leptons)obtain their masses from a differ.n. Higgs doublet H_f(f=u_1,d,e) .The conditions for anomaly cancellation imply that the remaining Higgs doublet of the model( H_(u_2) )must have the same hypercharge as H_(u_1) ,and thus,can only couple to up-type quarks,which opens the possibility to have FCnCs only in this *** study the Lagr.n.ian of the model,and in particular,the Higgs potential,to identify the Higgs mass-eigenstates and their interactions;for the Yukawa matrices,we consider the four-texture *** obtain constraints on the model parameters by using LHC measurements on the properties of the 125 GeV Higgs boson(h),and identify viable regions of the parameter ***,these constraints are used to evaluate the prospects for detecting the FCnC decay mode t→ch at the future high-luminosity(HL)option for the LHC,which are compared with curr.n. limits from ***,we evaluate the FCnC decay of the next heavier Higgs boson H_(2)→tc ,which can typically reach Br(H_2→tc)≈(10^(-4)-10^(-5)) .The search for the signal at HL-LHC is also studied,and it is found that it may be detectable for specific regions of the model parameter space.

关键词： Higgs physics top quark supersymmetry collider physics

Mid-term survival of the Optimys short stem: A prospective case series of 500 patients

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World Journal of Orthopedics 2024年第3期15卷 257-265页

作者： bryan Hamans Sheryl de Waard Sjoerd Kaarsemaker Esther r C Janssen Inger.n.Sierevelt Gino M M J Kerkhoffs Daniël Haverkamp Department of Orthopaedic Surgery Xpert ClinicAmsterdam 1101EANetherlands Department of Orthopedic Surgery Amsterdam University Medical CenterAmsterdam 1105 AZNetherlands Esther r C Janssen Department of Orthopaedic SurgeryViecuri Medisch CentrumVenlo 5912 BLNetherlands Centre for Orthopaedic research Spaarne ZiekenhuisHoofddorp 2134 TMNetherlands Department of Orthopaedic Surgery and Sports Medicine Amsterdam UMC-Location AMCAmsterdam 1105 AZNetherlands Department of Orthopedic Surgery Xpert Orthopedic Surgery ClinicAmsterdam 1101 EANetherlands

BACKGrOUnD In recent years,there has been an increase in the number of total hip arthroplasty procedures in the younger patient *** active group has higher expectations of their prosthesis in comparison to the older population,and there is a greater physical demand for the *** femoral stems were in-troduced to retain proximal bone stock and joint biomechanics and became more common to implant in this specific ***,the long-term survival and functional outcomes of various short stems are still being investigated in differ.n. *** To determine the 5-year survival of the Optimys hip *** This was a prospective multicenter cohort study of 500 patients conducted in two hospitals in the *** patients received the Optimys short stem(Mathys Ltd,Bettlach,Switzerland).The primary outcome measure was survival of the hip stem,with revision as the *** secondary outcome measurements included patient-reported outcome measures(PrOMs).Kaplan-Meier analysis was used to calculate the 5-year survival ***-minus-log tr.n.formation was performed to calculate the 95%confidence interval(95%CI).Mixed model analyses were performed to assess the course of the PrOMs dur.n. the 1st 2 years after *** were modeled separately for the 1st and 2nd years to calculate the yearly change in PrOMs dur.n. both follow-up periods with accompanying 95%*** The mean age of the total 500 patients was 62.3 years(standard deviation:10.6)and 202 were male(40%).At a median follow-up of 5.5 years(interquartile r.n.e:4.5-6.7),7 patients were deceased and 6 revisions were registered,for infection(n=3),subsidence(n=2)and malposition(n=1).This resulted in an overall 5-year survival of 98.8%(95%CI:97.3-99.5).If infection was left out as reason for revision,a stem survival of 99.4%(95%CI:98.1-99.8)was *** questionnaires were completed by 471 patients(94%),317 patients(63%)completed the 1-year follow-up questionna

关键词： Total hip arthroplasty Femoral stem Short stem Optimys Survival 5-year survival revision PrOMs

C:n:P stoichiometry and nutrient limitation of the soil microbial biomass in a grazed grassland site under experimental P limitation or exces

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Ecological Processes 2012年第1期1卷 66-76页

作者： bryan S Griffiths Annette Spilles Michael Bonkowski Teagasc Environment Research CentreJohnstown CastleWexfordCoWexfordIreland Curr.n. address:SAC King's BuildingsWest Mains RoadEdinburgh EH93JGUK Mathematisch naturwissenschaftliche Fakultät der Universität zu Köln Zoologisches Institut Abt.TerrestrischeÖkologieBiowissenschaftliches ZentrumOtto-Fischer-Str.6D-50674KölnGermany

Introduction:The availability of essential nutrients,such as nitrogen(n)and phosphorus(P),can feedback on soil carbon(C)and the soil microbial *** cycles can be supplemented by agricultural fertiliser addition,and we determined whether the stoichiometry and nutrient limitation of the microbial biomass could be affected by an unbalanced nutrient ***:Samples were taken from a long-term trial(in effect since 1968)with annual applications of 0,15 and 30 kg P ha^(−1) with constant n and *** and microbial biomass CnP contents were measured and nutrient limitation assessed by substrate-induced *** regression and discriminant analyses were used to identify the variables explaining nutrient ***:Soil and biomass CnP increased with increasing P fertiliser,and there was a significant,positive,correlation between microbial biomass P and biomass C,apart from at the highest level of P fertilisation when the microbial biomass was over-saturated with *** molar ratios of C:n:P in the microbial biomass remained constant(homeostatic)despite large changes in the soil nutrient *** growth was generally limited by C and n,except in soil with no added P when C and P were the main limiting nutrients.C,n and P,however,did not explain all the growth limitation on the soils with no added ***:Increased soil C and n were probably due to increased net primary *** results confirm that C:n:P ratios within the microbial biomass were constrained(***)under.n.ar optimum soil *** with no added P were characterised by str.n. microbial P limitation and soils under high P by over-saturation of microorganisms with *** changes in biomass C:P can be indicative of nutrient limitation within a site.

关键词： Carbon nitrogen nutrient limitation Phosphorus Soil microbial biomass Stoichiometry

EFFECTS OF rIVEr ICE On STAGE-DISCHArGE rELATIOnSHIPS——A CASE STUDY OF THE YELLOW rIVEr

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International Journal of Sediment research 2007年第4期22卷 263-272页

作者： r.n.ld THr.n. bryan W. KArnEY Prof. Environmental Engineering University of Northern British Columbia 3333 University Way Prince George BC Canada V2N 4Z9 Prof. Department of Civil Engineering University of Toronto 35 St. George Street Toronto ON Canada M5S 1A4

Using field observations at four gauging stations along the Inner Mongolia reach of the Yellow river in China, this paper explores effects of the ice on the hydraulics of this river reach for four differ.n. conditions, namely: under open channel flow, dur.n. ice-r.n.ing period, the ice-covered period, and the river break-up period. The rating curves were found to be well recognized under open channel situations, but were sometimes poorly defined and extremely variable under ice conditions. The results also show that the water level is insensitive to flowing ice prior to freeze-up. However, significant, but hardly surprising, variations were observed dur.n. ice-covered conditions. The rating curves for both the ice covered condition and river ice breakup period are developed and some related hydraulic issues are examined. Additionally, the impacts of the ice accumulation and associated riverbed deformation dur.n. ice period on the rating curves are discussed.

关键词： Ice-r.n.ing period Ice covered period rating curve riverbed deformation river ice break-up

Impacts of late Quaternary envir.n.ental change on the long-tailed ground squirrel(Urocitellus undulatus)in Mongolia

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Zoological research 2018年第5期39卷 364-372页

作者： bryan S.McLean Batsaikhan nyamsur.n.AnDrey Tchabovsky Joseph A.Cook University of Florida Florida Museum of Natural History Department of Biology School of Arts and Sciences National University of Mongolia Laboratory of Population Ecology A.N. Severtsov Institute of Ecology and Evolution University of new Mexico Department of Biology and Museum of Southwestern Biology

Impacts of Quaternary envir.n.ental changes on mammal faunas of central Asia remain poorly understood due to a lack of comprehensive phylogeographic sampling for most *** help address this knowledge gap,we conducted the most extensive molecular analysis to date of the long-tailed ground squirrel （Urocitellus undulatus Pallas 1778） in Mongolia,a country that comprises the southern core of this species＇ *** on material from recent collaborative field expeditions,we genotyped 128 individuals at two mitochondrial genes （cytochrome b and cytochrome oxidase Ⅰ;1797 bp total）.Phylogenetic infer.n.e supports the existence of two deeply divergent infraspecific lineages （corresponding to subspecies *** and ***）,a result in agreement with previous molecular investigations but discordant with patterns of r.n.e-wide cr.n.ometric and external phenotypic *** the widespread western eversmanni lineage,we recovered geographically-associated clades from the：（a） Khangai,（b） Mongolian Altai,and （c） Govi Altai mountain *** structure in *** is consistent with an isolation-by-distance model;however,genetic distances are significantly lower than among subspecies,and intra-clade relationships are largely *** latter patterns,as well as the relatively higher.n.cleotide polymorphism of populations from the Great Lakes Depression of northwestern Mongolia,suggest a history of r.n.e shifts into these lowland areas in response to Pleistocene glaciation and envir.n.ental change,followed by upslope movements and mitochondrial lineage sorting with Holocene *** study illuminates possible historical mechanisms responsible for *** genetic structure and contributes to a framework for ongoing exploration of mammalian response to past and present climate change in central Asia.

关键词： Central Asia Gobi Desert Great LakesDepression Mongolia Phylogeography

The effect of milling additives on powder properties and sintered body microstructure of niO

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Journal of Advanced Ceramics 2015年第2期4卷 142-151页

作者： L.Jay DEInEr Michael A.rOTTMAYEr bryan C.EIGEnBrODT Department of Chemistry New York City College of TechnologyCity University of New York300 Jay St.BrooklynNY 11201USA The Air Force research Labs Wright-Patterson Air Force BaseOH 45433USA Department of Chemistry Villanova University800 E.Lancaster Ave.VillanovaPA 19085USA

The evolution of powder particle size,crystal structure,and surface chemistry was evaluated for micr.n.scale niO powders subjected to impact milling with commonly employed milling additives:methanol,Vertrel XF,and amorphous *** effect of the differ.n. comminution protocols on sintered body microstructure was evaluated for high temperature sinter.n. in inert atmosphere(n_(2)).X-ray photoelectr.n.spectroscopy showed that niO powder surface chemistry is surprisingly sensitive to milling additive *** particular,the proportion of powder surface defect sites varied with additive,and methanol left an alcohol or alkoxy residue even after *** sinter.n. to intermediate temperatures(1100℃),scanning electr.n.microscopy(SEM)showed that slurry milled niO powders exhibit hindered sinter.n. *** effect was amplified for.n.O milled with methanol,in which sub-500 nm grain sizes dominated even after sinter.n. to 1100℃.Upon heating to high temperatures(1500℃),simultaneous differ.n.ial scanning calorimetry/thermogravimetric analysis(DSC/TGA)showed that the powders containing carbon residues undergo carbothermal reduction,resulting in a melting tr.n.ition between 1425 and 1454℃.Taken together,the results demonstrated that when processing metal oxide powders for advanced ceramics,the choice of milling additive is crucial as it exerts significant control over sintered body microstructure.

关键词： nickel oxide impact milling sinter.n. densification grain growth

InCIPIEnT MOTIOn OF nOn-COHESIVE SEDIMEnT UnDEr ICE COVEr-An EXPErIMEnTAL STUDY

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Journal of Hydrodynamics 2008年第1期20卷 117-124页

作者： WAnG Jun SUI Jue-yi KArnEY bryan W. School of Civil Engineer.n. Hefei University of Technology Hefei 230009 China Envir.n.ental Science and Envir.n.ental Engineer.n. Program University of Northern British ColumbiaBritish Columbia Canada V2N 4Z9 Department of Civil Engineer.n. University of Toronto Toronto Ontario Canada M5S 1A4

Based on a series of experiments under both ice-covered and free surface conditions, the present article discusses the role of flow velocity and critical shear reynolds number for incipient motion of bed material. The influence of the resistance coefficients of both the underside of the ice cover and the channel bed on the location of the maximum velocity has been discussed. In addition, the impacts of ice and composite resistance coefficients on flow velocity for incipient motion of bed material have been assessed. The diagram describing the critical shear reynolds number and the dimensionless shear stress for the incipient motion of sediment under ice covered conditions with differ.n. under cover resistance coefficient has been established. The effects of grain size on densimetric Froude number for incipient motion of bed material have been investigated. A relationship between the densimetric Froude number for incipient motion of bed material and the median grain size of bed material as well as the roughness coefficient of channel bed and roughness coefficient of ice cover has been established.

关键词： densimetric Froude number grain size ice cover incipient motion resistance coefficient shear reynolds number,velocity