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Mixtures of tetrakis hydroxymethyl phosphonium chloride and ammonium influence plankton community structure in blackwater pond mesocosms

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Emerging Contaminants 2020年第1期6卷 62-71页

作者： marina n.Osier Risa A.Cohen Department of Biology Georgia Southern UniversityPO Box 8042-1StatesboroGA30460USA

Mixtures of chemicals from human sources are pervasive in aquatic systems,yet their effects on aquatic communities are relatively *** contaminants such as organophosphorus flameretardants(*** hydroxymethyl phosphonium chloride(THPC)),are toxic to planktonic species at environmentally relevant ***,inorganic ammonium from agriculture and industry is likely to enter surface waters simultaneously with flame retardant *** effects of ammonium on plankton are known,its presence has the potential to influence the toxicity of other *** study mixture effects on plankton communities,floating mesocosms were dosed with THPC(0.08 or 0.8 mg L^-1)with or without ammonium(0.3 mg L^-1).Weekly measurements of zooplankton community composition and phytoplankton abundance(as chlorophyll a)were *** factor alone had no effect on zooplankton abundance or species ***,the mixture decreased the proportion of calanoid copepods and increased rotifers during weeks *** a was unaffected by treatments,but concentrations were highly variable for the duration of the *** interaction between THPC and ammonium suggests that the contaminants together reduce abundance of large zooplankton,releasing smaller zooplankton from predation and competitive pressure while potentially limiting food availability to planktivorous fish.

关键词： Emerging contaminant Flame retardant Freshwater nitrogen Phytoplankton Zooplankton Ecotoxicology

Migration from an SQL to a hybrid SQL/noSQL data model

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Journal of Management Analytics 2020年第1期7卷 1-11页

作者： marina V.Sokolova Francisco J.Gomez Larisa n.Borisoglebskaya Orel State University OrelRussia Department of Computing Systems University of Castilla-La ManchaAlbaceteSpain

The paper presents a redesign of a database management system for a retail business ***,based on a traditional data model,it is migrated to a hybrid model which combines both SQL and noSQL *** approach adds flexibility,mobility,and efficiency to the data management *** noSQL database uses an ontology as a data schema,which we describe in this *** noSQL database is consulted using the SPARQL query language,and some examples of the queries are detailed in the *** architecture of the system and its functionality are discussed.

关键词： noSQL ontology digitalization RDF

ZnSe/niO heterostructure-based chemiresistive-type sensors for low-concentration nO_(2) detection

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Rare Metals 2021年第6期40卷 1632-1641页

作者： Wei Liu Ding Gu Jian-Wei Zhang Xiao-Gan Li marina n.Rumyantseva Alexander M.Gaskov School of Microelectronics Key Laboratory of Liaoning for Integrated Circuits TechnologyDalian University of TechnologyDalian 116024China Liaoning Key Laboratory of Integrated Circuit and Biomedical Electronic System Faculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalian 116024China Laboratory of Chemistry and Physics of Semiconductor and Sensor Materials Chemistry DepartmentMoscow State UniversityMoscow 199991Russia

novel ZnSe/niO heterostructure nanocomposites were successfully prepared by one-step hydrothermal *** ZnSe/niO-based sensor exhibits a response of~96.47% to 8×10^(-6) nO_(2) at 140℃,which is significantly higher than those of intrinsic ZnSe-based(no response)and niO-based(~19.65%)*** theoretical detection limit(LOD)of the sensor is calculated to be 8.91×10^(-9),indicating that the sensor can be applied to detect the ultralow concentrations of nO_(2).The effect of niO content on the gas-sensing performance of the nanocomposites was investigated in *** optimal niO content in the nanocomposite is determined to be15.16%to achieve the highest *** as-fabricated sensor also presents an excellent selectivity to several possible interferents such as methanol,ethanol,acetone,benzene,ammonia and *** enhanced sensing performance can be attributed to the formation of p-p heterostructures between ZnSe and niO,which induces the charge transfer across the interfaces and yields more active sites.

关键词： ZnSe/niO heterostructure nO_(2)detection Gas sensors Charge transfer

Chiral Fermion Conductivity in Graphene-Like Samples Subjected to Orthogonal Fields

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Chinese Physics Letters 2012年第1期29卷 20-23页

作者： Ciprian Dariescu marina-Aura Dariescu Faculty of Physics Alexandru Ioan Cuza University of IaşiBd.Carol I No.11700506 IaşiRomania

Starting with the U(1)-gauge covariant four-dimensional Dirac equation,we derive the analytic solutions describing the chiral massless fermions evolving in static orthogonal magnetic and electric *** in cylindric coordinates,we compute the electric current density essential component and the off-diagonal *** summing up the conductivities of the two distinct species of electrons connected to the orientation of spin,the well-known 4n-quantization law is restored.

关键词： Fermi diagonal Conductivity

Gold mineralisation and orogenic metamorphism in the Lena province of Siberia as assessed from Chertovo Koryto and Sukhoi Log deposits

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Geoscience Frontiers 2016年第3期7卷 453-481页

作者： marina A.Yudovskaya Vadim V.Distler Vsevolod Yu.Prokofiev nickolay n.Akinfiev Institute of Geology of Ore Deposits PetrographyMineralogy and Geochemistry RAS EGRI University of the Witwatersrand

The Chertovo Koryto gold deposit（80 t Au at 1.84 g/t） in the Lena world-class province,Siberia,is hosted in a metamorphosed sequence of the Paleoproterozoic Mikhailovsk Formation that comprises the oldest black shale strata of the Baikal-Patom *** mineralisation is confined to the thrust zone complicated with a conjugate anticline fold,zones of shearing and *** struaural position of the mineralisation is similar to that at the giant Sukhoi Log deposit in the neighbouring Mama-Bodaibo *** the latter,the isotope age data suggest that Khomolkho black shales,hosts to Sukhoi Log mineralisation,are of Ediacaran age and underwent prograde metamorphism during early *** geochemical composition of the terrigenous rocks that host Sukhoi Log,Chertovo Koryto,and a number of other deposits at the various stratigraphic levels throughout the Proterozoic sequence have much in *** do not show elevated metal contents above the common black shale abundances,except for Au and As,which is at variance with the accepted view on diagenetic enrichment of black shales in the Lena *** occurrence of sagenitic rutile in quartz and chlorite pseudomorphs after biotite and other petrographic observations provide evidence on a retrograde nature of the metamorphic mineral assemblages in the Mikhailovsk *** sulphides are pyrrhotite and arsenopyrite with very minor pyrite at Chertovo Koryto,whereas pyrite is the predominant sulphide in the Sukhoi Log *** inclusion data on both deposits emphasise a high-temperature nature of the mineralisation albeit revealing great contrast in the fluid *** Log mineralisation was formed at mixing between low-salinity aqueous solutions and dense gaseous carbonic fluids,which facilitated effective gold scavenging and precipitation,as demonstrated by thermodynamic *** precursory devolatilisation of the Mikhailovsk sediments at the prograde stage results in the paucity of gaseous carbon

关键词： Gold Black shales Orogenic metamorphism Orogenic fluid Sukhoi Log Chertovo Koryto

Influence of soil and elevation on roadside cryptogam diversity in the tropical Andes

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Forest Ecosystems 2022年第5期9卷 639-646页

作者： Paul Salinas marina Mazon Vinicio Carrion-Paladines nixon Cumbicus Patricio Guzman Paolo Giordani Angel Benítez Maestría en Biología de la Conservacion y Ecología Tropical Universidad Tecnica Particular deLojaSan Cayetano Alto s/nLoja1101608Ecuador Centro de Investigaciones Tropicales del Ambiente y Biodiversidad–CITIAB Universidad Nacional de LojaCiudadela Universitariasector La ArgeliaEC 110101LojaEcuador Biodiversidad de Ecosistemas Tropicales-BIETROP Herbario HUTPLDepartamento de Ciencias Biologicas y AgropecuariasUniversidad Tecnica Particular de LojaSan Cayetano Alto s/nLoja1101608Ecuador Departament of Pharmacy University of GenoaViale Cembrano 416148GenoaItaly

Background: The deforestation caused by road construction is one of the main drivers for both biodiversity and function loss in tropical ecosystems. Terricolous cryptogams are pioneers in colonizing roadside and they are limited by environmental and edaphic factors, thus, cryptogams may act as pioneers for ecosystem rehabilitation at ***: This research was aimed at determining the diversity and composition of terricolous cryptogams, as well as their relationship with elevation and soil properties among roadside of the tropical Andes of Ecuador, in order to establish indicator species of this anthropized ecosystems. Five elevations were selected and in each one 50grids of 20 cm×30 cm were sampled(250 in total along the road), where occurrence, cover and identification of every cryptogam species were recorded. To evaluate the effect of elevation and soil properties on cryptogam richness, a linear model was conducted. Species composition among elevations was compared by non-metric multidimensional scaling(nMDS), and their relationship with the environmental variables through a correlation with adjusted axes was performed. A total of 72 species were recorded, those being 44 bryophytes and 28lichens. Species richness and composition of terricolous cryptogams were influenced by elevation and soil properties, thus the richness is higher at elevations E1, E2 and E3(2600, 2200 and 1800 m a.s.l.), differing from low elevations E4 and E5(1400 and 1000 m a.s.l.). Higher elevations with specific soil conditions(e.g bulk density, nitrogen and silt) harbored different cryptogam communities than those in lower ***: A combination of both elevation and soil properties are shaping the colonization by terricolous cryptogams commnunities. As such, 18 species were identified as the best indicators for all sets of environmental conditions at the roadside, which can therefore be considered for monitoring ecological processes in tropical areas. Use of biocrus

关键词： Bryophytes Indicator species Beta diversity Lichens Richness Ecuador

Biogeochemical conversion of sulfur species in saline lakes of Steppe Altai

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Journal of Oceanology and Limnology 2018年第3期36卷 676-686页

作者： BORZEnKO Svetlana V. KOLPAKOVA marina n. SHVARTSEV Stepan L. ISUPOV Vitaly P. Institute of natural Resources Ecology and CryologySiberian Branch of Russian Academy of SeiencesChita 672049Russia Sobolev Institute of Geology and Mineralogy Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia national Research Tomsk Polytechnic University Tomsk 634050Russia Tomsk Department of the Trofimuk Institute of Petroleum-Gas Geology and Geophysics Siberian Branch of the Russian Academy of SciencesTomsk 634050Russia Institute of Solid State Chemistry and Mechanochemistry Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia

The aim of the present research is to identify the main mechanisms of sulfur behavior in saline lakes in the course of time and followed transformations in their chemical composition. The influence of water on chemical composition of biochemical processes involved in decomposition of organic matter was determined by the study of behavior of reduced forms of sulfur in lakes. The determination of reduced forms of sulfur was carried out by successive transfer of each form of sulfur to hydrogen sulfide followed by photometric measurements. The other chemical components were determined by standard methods(atomic absorption, potentiometric method, titration method and others). The salt lakes of the Altai steppe were studied in summer season 2013–2015. Analysis of the chemical composition of the saline lakes of Altai Krai has shown that carbonate-, hydrocarbonate-and chloride ions dominate among anions; sodium is main cation; sulfates are found in subordinate amounts. Reduced forms of sulfur occur everywhere: hydrogen and hydrosulfide sulfur S^(2-) prevail in the bottom sediments; its derivative—elemental S^0—prevails in the lakes water. The second important species in water of soda lakes is hydrosulfide sulfur S^(2-), and in chloride lakes is thiosulfate sulfur S_2O_2^(3ˉ). The lag in the accumulation of sulfates in soda lakes in comparison to chloride lakes can be explained by their bacterial reduction, followed by the formation and deposition of iron sulfides in sediments. In chloride lakes gypsum is a predominantly barrier for sulfates.

关键词： saline lake sulfate reduction gypsum Altai

Measurements of Laminar Burning Velocities of Alternative Fuels:Application in Transport and Aerospace

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Journal of Thermal Science 2023年第2期32卷 503-512页

作者： RICHTER Sandra BRAUn-UnKHOFF marina nAUMAnn Clemens German Aerospace Center(DLR) Institute of Combustion TechnologyDepartment of Chemical Kinetics and AnalyticsStuttgart 70569Germany

The laminar burning velocity belongs to the fundamental combustion properties of fuels being a measure for their heat release,flame length,as well as reactivity and combustion stability,and thus,may impact the design of burners and combustion ***,these experimental data are needed for the validation and optimization within the construction and development of detailed chemical kinetic reaction *** this study,an overview of the different applications of fuel characterization regarding the specific area of interest(road transport,aviation,and aerospace)will be *** on the application,effects of different molecular characteristics on the laminar burning velocity are evaluated:the presence of oxygen atoms and the grade of branching in a specific fuel molecule as well as the difference in the type of a chemical bond,here,single and double *** of alternative fuels being discussed in the present study are:(Ⅰ)oxymethylene ether(OMEn)in the field of road transport;(Ⅱ)a paraffinic Alcohol-to-Jet fuel as sustainable aviation fuel;and(Ⅲ)mixtures of ethane or ethene with nitrous oxide as green propellants for rocket propulsion applications.

关键词： laminar burning velocity alternative sustainable fuels road transport aviation fuels green propellants

Changing delta hepatitis patient profile:A single center experience in Valencia region,Spain

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World Journal of Hepatology 2020年第6期12卷 277-287页

作者： Helena Hernàndez-Èvole Álvaro Briz-Redón marina Berenguer Departament de Medicina University of ValènciaValencia 46010Spain Statistics Office City Council of ValènciaValencia 46002Spain Liver Transplantation and Hepatology Unit Hospital Universitari I Politècnic La FeValencia 46026Spain CIBERehd Instituto de Salud Carlos ⅢMadrid 28029Spain ISS La Fe Valencia 46026Spain

BACKGROUnD Delta hepatitis is a rare infection with an aggressive disease *** almost three decades,however,there have been no epidemiological studies in our traditionally endemic *** To investigate the prevalence of delta hepatitis in a sample of patients with chronic hepatitis B virus(HBV)infection followed at a Hepatology Unit in Valencia,*** Retrospective evaluation of anti-hepatitis D virus-immunoglobulin G seroprevalence among patients with chronic HBV infection(n=605)followed at a reference Hepatology Unit in *** The prevalence of anti-hepatitis D virus-immunoglobulin G among HBV-infected patients was 11.5%:Male(63%)and median age of 52 *** majority were born in Spain(67%)and primarily infected through intravenous drug ***,a significant percent(24.5%),particularly those diagnosed in more recent years,were migrants presumably nosocomially *** such as diabetes(8.5%),obesity/overweight(55%),and alcohol consumption(34%)were frequent.A high proportion of patients developed liver complications such as cirrhosis(77%),liver decompensation(81%),hepatocellular carcinoma(HCC)(16.5%),or required liver transplantation(LT)(59.5%).Diabetes was associated with progression to cirrhosis,LT,and *** sex,increasing age,and alcohol were associated with LT and *** to HBV mono-infected patients,delta individuals developed cirrhosis and liver decompensation more frequently,with no differences in HCC *** Patients infected in the 1980’s were mostly locals infected through intravenous drug use,whereas those diagnosed recently are frequently non-Spanish natives from endemic *** of their origin,patients are predominantly male with significant comorbidities,which potentially play a major role in disease *** confirm a high rate of subsequent liver complications.

关键词： Viral hepatitis Delta hepatitis Cirrhosis Liver transplantation Immigration Valencia