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Conductometric Titration for the Prediction of Conductivity in Solutions with Polymeric Membranes

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Journal of Electronic Science and Technology 2017年第4期15卷 342-350页

作者： maría José Lavorante Juan isidro Franco Research and Development of Renewable Energy Department at CiTEDEF Institute of Scientific and Technical Research for the Defense Villa Martelli B1603ALO Argentina

The analytical technique of conductometric titration is used to characterize polymeric *** technique allows obtaining the polymer dry weight capacity(DWC) and the extent of reaction and establishing the optimal number of water molecules per sulfonic *** this particular case the polymer material under study was Nafion?*** different reactions were made: Neutralization and *** of them allow obtaining the same *** titrations could be considered as a good method to study the neutralization and exchange reactions for polymeric materials used in fuel cells or *** implementation of this analytical technique allows reducing operation time of those types of *** waiting time between determinations per.its to say that the amount of reactant consumed and products obtained were the same after each addition of titrant.

关键词： Conductivity conductometric titration polymeric membranes

Tracking the change in Spanish greenhouse gas emissions through an LMDi decomposition model:A global and sectoral approach

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Journal of Environmental Sciences 2024年第5期139卷 114-122页

作者： Paula Fernández González maría José Presno Manuel Landajo Department of Applied Economics University of OviedoAuda del Cristos/n 33011 OviedoSpain

The reduction of GHG emissions to reverse the greenhouse effect is one of the main challenges in this *** this paper we pursue two ***,we analyze the evolution of GHG emissions in Spain in 2008–2018,at both the global and sectoral levels,with the variation in emissions decomposed into a set of determining ***,we propose several actions specifically oriented to more tightly controlling the level of *** results showed a remarkable reduction(18.44%)in GHG emissions,mainly due to the intensity effect,but also to the production-per-capita *** detected somewhat different patterns among the various sectors *** the intensity effect was the most influential one in the agricultural,transport,and others sectors,the production-per-capita effect was predominant in the case of *** carbonization effect was revealed as crucial in the commerce *** above findings highlight the importance of the energy efficiency measures taken in recent years in the Spanish economy,also pointing to the need to deepen those strategies and to propose new measures that entail greater efficiency in *** efforts in areas like innovation,R&D,diffusion of more eco-friendly technologies,and a greater use of greener energies all prove to be essential reduction actions to fight the greenhouse effect.

关键词： LMDi Decomposition Spain GHG emissions

influence of free fatty acid content and degree of fat saturation on production performance,nutrient digestibility,and intestinal morphology of laying hens

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Animal Nutrition 2023年第2期13卷 313-323页

作者： maría Palomar Carlos Garces-Narro olga Piquer Roser Sala Alba Tres Jose AGarcía-Bautista maría D.Soler AviFeed Science Department of Animal Production and HealthFacultad de VeterinariaUniversidad CEU Cardenal Herrera e CEU UniversitiesE-46115Alfara de PatriarcaValenciaSpain Animal Nutrition and Welfare Service Department of Animal and Food ScienceFacultat de VeterinariaUniversitat Autonoma de BarcelonaE-08193BellaterraBarcelonaSpain Departament de Nutrici Ciencies de l’Alimentaci i GastronomiaFacultat de Farmacia i Ciencies de l’AlimentaciUniversitat de BarcelonaE-08921Santa Coloma de GramenetBarcelonaSpain

This study was conducted to evaluate the effects of dietary free fatty acid(FFA)content and degree of fat saturation on production performance,lipid and calcium digestibility,and intestinal function of laying *** a 15-week period,a total of 144 laying hens(19 weeks old)were randomly assigned to 8 dietary treatments,which were obtained by gradually replacing crude soybean oil with soybean acid oil(Ao),or crude palm oil with palm fatty acid distillate(FAD).Thus,there were 4 soybean and 4 palm diets with 6%added fat varying in their FFA percentage(10%,20%,30%,and 45%),following a 2×4 factorial *** treatment included 6 replicates with 3 birds per *** daily feed intake and final body weight were significantly higher in palm diets(Pile no differences were found in egg mass and feed conversion *** levels of FFA in soybean diets resulted in lower egg production and higher egg weight(linear,Ping the degree of fat saturation,hens fed soybean diets presented higher digestibility of ether extract(EE),fatty acids,and calcium than palm diets(Pietary FFA percentage negatively affected the digestibility of EE and calcium(Pile having little effect on FA *** was a significant interaction in the AME;lower values were reported in soybean diets as the dietary FFA percentage increased(linear,Piets remained *** experimental diets had little effect on gastrointestinal weight and ***,the jejunum of soybean diets showed higher villus height and higher villus height-to-crypt depth ratio than palm diets(Pietary FFA percentage increased the crypt depth and decreased the villus height-to-crypt depth ratio(linear,Pit was concluded that varying dietary FFA content did not affect fat utilization as much as the degree of saturation did,supporting the use of Ao and FAD as alternative fat ingredients.

关键词： Acid oil Fat by-product Fatty acid distillate Lipid Calcium

Soil seed bank assembly following secondary succession on abandoned agricultural fields in Nicaragua

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Journal of Forestry Research 2009年第4期20卷 349-354,I0006页

作者： Benigno González-Rivas Mulualem Tigabu Guillermo Castro-marín per Christer odén Facultad de Recursos Naturales y del Ambiente. Universidad Nacional Agraria. Managua Swedish University of Agricultural Sciences Faculty of Forest Sciences Southern Swedish Forest Research Centre Sweden.

The composition and density of seeds in soils of secondary forests derived on abandoned fields after 4, 9 and 14 years of aban- donment were quantified to examine whether the soil seed bank assembles during secondary succession as the plant communities assemble. A total of 18, 37 and 48 soil samples from 4-, 9- and 14-year old sites, respectively were collected in 15 cm × 15 cm plots up to 9 cm depth. A total of 3, 5 and 9 species were found on sites abandoned 4, 9 and 14 years ago, respectively, Among different life forms, trees were highly represented in the soil seed bank of 9-year （60%） and 14-year （33%） old sites compared to 4-year old site entirely dominated by non- woody flora. The total number of seeds ranged from 327 in the 4-year old site to 146 in the 14-year old site, and the corresponding density of viable seeds ranged from 141 seeds m^-2 in the 4- year old site to 26 seeds m^-2 in the 14-year old site with a consistent decreasing pattern in the chronosequence. The similarity between the soil seed flora and the standing woody vegetation was low for both 9- and 14-year old sites while complete dissimilarity was found for 4-year old site. We concluded that the species composition of soil seed banks assemble gradually during secondary succession, but the overall seed density is still low for natural regeneration of trees to rely on. To expedite the recovery of secondary forests on such abandoned fields, the seed bank needs to be supplemented by direct seeding, enrichment planting of desired species and installing artificial perches for facilitating seed dispersal.

关键词： seed dispersal dry forest seed bank secondary succession restoration Nicaragua

Alternatives of Small-Scale Biorefineries for the integrated Production of Xylitol from Sugarcane Bagasse

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Journal of Renewable Materials 2018年第2期6卷 139-151页

作者： Nicolás M.Clauser Soledad Gutiérrez maría C.Area Fernando E.Felissia maría E.Vallejos Materials institute of Misiones(iMAM) National University of Misiones–National Council of Scientific and Technical Research(UNaM–CONICET)1552 Félix de Azara St.(3300)PosadasMisionesArgentina Faculty of Engineering University of the Republic(UDeLaR)565 Julio Herrera y Reissig St.(11700)MontevideoUruguay

Small-scale biorefinery from sugarcane bagasse offers new possibilities to the sugar and ethanol *** aim of this study was to evaluate the feasibility of a small-scale biorefinery for the production of xylitol from sugarcane *** liquid fraction from the autohydrolysis treatment was selected as the source of sugars for xylitol and two scenarios were analyzed for the residual solid:ethanol or pellet production.A technical-economic analysis of alternatives was *** internal rate of return(iRR)was used to compare the selected *** highest iRR values were obtained when processing 70,000 dry tons per year of *** results showed promising prospects for a small-scale biorefinery with capacities above 20,000 dry tons per year(xylitol and pellets),and above 50,000 dry tons per year(xylitol and ethanol).

关键词： Biorefinery sugarcane bagasse xylitol ethanol pellets

A chronosequence analysis of forest recovery on abandoned agricultural fields in Nicaragua

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Journal of Forestry Research 2009年第3期20卷 213-222,286页

作者： Guillermo Castro marín Mulualem Tigabu Benigno González-Rivas per Christer odén Facultad de Recursos Naturales y del Ambiente Universidad Nacional Agraria Swedish University of Agricultural Sciences Faculty of Forest Sciences Southern Swedish Forest Research Centre Tropical Silviculture and Seed Laboratory

Species composition, diversity and population structure of woody species recovered on three abandoned agricultural fields after 4, 9 and 14 years were characterized. Seedlings, saplings/poles and mature trees were identified and counted in 70 plots of 100 m2 in each abandoned site. A total of 13, 29 and 22 families represented by 17, 48 and 44 species were registered in 4-, 9-and 14-year-old stands, respectively. There was a shift in dominant species across successional stages. Lonchocarpus acuminatus had the highest importance value in the 4-year old stand, whereas, Myrospermun frutescens, Guazuma ulmifolia and Cordia alliodora had the highest importance value in the 9-year-old-stand and Caesaeria corymbosa, Muntingia calabura, Gliricidia sepium and Tabebuia rosea in the 14-year-old stand. The total stem density increased from 5011 to 9631 individuals per hectare as the age of abandonment increased from 4 to 14 years. The total basal area of individuals ≥ 1cm d.b.h. also increased with the age of abandonment. overall, small individuals (ontributed to more than half of the total basal area. Species diversity was the highest in the 9-year old stand followed by 14-and 4-year-old stands. We concluded that floristic composition of secondary forests recovers rapidly to the mature forest level compared to structural attributes, which is consistent with the general successional trajectories of tropical dry forest.

关键词： Central America dry forest Neotropics restoration secondary succession abandoned agricultural field forest recovery

Potential role of lava lizards as pollinators across the Galápagos islands

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integrative Zoology 2020年第2期15卷 144-148页

作者： Sandra HERVÍAS-PAREJo Manuel NoGALES Beatriz GUZMÁN maría del mar TRiGo Jens MoLESEN Pablo VARGAS Ruben HELENo Anna TRAVESET Global Change Research Group Mediterranean Institute for Advanced StudiesMallorcaBalearic IslandsSpain island Ecology and Evolution Research Group Institute of Natural Products and AgrobiologyCanary IslandsSpain Royal Botanical Garden of Madrid MadridSpain Department of Plant Biology Málaga UniversityMálagaSpain Department of Bioscience Aarhus UniversityAarhusDenmark Centre for Functional Ecology Department of Life SciencesUniversity of CoimbraCoimbraPortugal

Lizards have been reported as important pollinators on several oceanic *** we evaluate the potential role of Galápagos lava lizards(Microlophus spp.)as pollinators across their *** 3 years,we sampled pollen transport by 9 lava lizard species on the 10 islands where they are present,including 7 single-island ***,only 25 of 296 individuals sampled(8.4%)transported pollen of 10 plant species,the most common being Prosopis juliflora,Exodeconus miersii,Sesuvium *** Cordia *** least 8 of these plant species were native,and none were confirmed as introduced to the *** the low overall proportion of individuals carrying pollen,this was observed in 7 of the nine lizard species,and on 8 of the ten main islands(Española,Fernandina,Floreana,isabela,marchena,Pinta,Santa Cruz and Santiago),suggesting that this is a widespread *** results reported here support the potential role of lava lizards as pollinators across their radiation,although they may represent a relatively modest contribution when compared with birds and ***,we cannot discard that lizards may be ecologically significant for particular plant species and ecosystems given the specific climatic condition and functional diversity of each island.

关键词： flower visitation Microlophus spp. mutualistic interactions pollination vertebrate radiation

Cardiovascular risk factors and frontotemporal dementia: a case–control study

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Translational Neurodegeneration 2014年第1期3卷 98-103页

作者： Angel Golimstok Nuria Cámpora Juan i Rojas maría C Fernandez Cristina Elizondo Enrique Soriano Edgardo Cristiano Cognitive and Behavior Unit Department of NeurologyHospital Italiano de Buenos AiresPerón 42721411 Buenos AiresArgentina Department of Neurology Hospital Italiano de Buenos AiresBuenos AiresArgentina Epidemiology Department Hospital Italiano de Buenos AiresBuenos AiresArgentina

Cardiovascular risk factors(CRF)were widely described as related to *** are very few studies regarding this association in *** objective of the study was to compare the frequency of CRF in our population with FTD and controls.100 consecutive subjects with FTD diagnosis according to Lund-Manchester clinical criteria and 200 controls matched by age and sex were included between January 2003 to February 2007 at the Cognitive and Behavior Unit of Hospital italiano de Buenos *** evaluation,laboratory tests,brain images(CT/MRi),neuropsychological and neuropsychiatric assessment were *** regression analysis was performed to analyze the association in CRF between FTD patients *** mean age in FTD was 69.7±0.9 vs.70.1±0.8 in controls(p 0.12).No difference in gender was observed between cases and *** differences were identified between patients and controls regarding hypertension(HTA)(65%vs.67,3%p 0.44);dyslipidemia(57%vs.54.7%p 0.74);obesity(39%vs.27.6%p 0.14)and hypothyroidism(26%vs.17.1%p 0.1).A significant difference was observed for Diabetes Mellitus(39%vs.22.6%p 0.001).in our population,Diabetes Mellitus was associated as an independent risk factor for *** our knowledge this is the first report in which CRF were evaluated prospectively in FTD *** studies are needed to confirm this finding in larger populations.

关键词： Cardiovascular risk factors Frontotemporal dementia Dementia FTD Diabetes DBT DM

Potential of Bamboo Species Guadua trinii and Guadua angustifolia for Nanocellulose Production

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Journal of Renewable Materials 2024年第9期12卷 1541-1555页

作者： Agatha E.R.Prado Gárate Fernando E.Felissia maría Cristina Area Teresa Suirezs maría Evangelina Vallejos Círculo de investigación del Bambú Universidad Nacional Agraria La Molina(UNALM)Lima15026Perú instituto de Materiales de Misiones(iMAM) Universidad Nacional de Misiones(UNaM)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Facultad de Ciencias ExactasQuímicas y Naturales(FCEQYN)Programa de Celulosa y Papel(PROCyP)Posadas3300Argentina instituto de Materiales de Misiones(iMAM) Universidad Nacional de Misiones(UNaM)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Facultad de Ciencias Forestales(FCF)Eldorado3380Argentina

Non-traditional lignocellulosic materials are a significant resource for producing high-value products,including *** work studied the nanocellulose obtention from chemical pulps of the two fast-growing bamboo species,Guadua trinii,and Guadua *** pulps were produced by soda-anthraquinone(S)pulping from both autohydrolysis-pretreated(H)and unpretreated bamboo ***-pretreated(SHP)and unpretreated soda-anthraquinone(AQ)(SP)pulps were characterized by yield,Kappa number,alpha,beta,and gamma cellulose,degree of polymerization,water retention value,and *** nanocellulose was produced by a sequential chemical oxidation treatment(2,2,6,6-tetramethylpiperidine-1-oxyl,TEMPo reagent)and mechanical *** was characterized by carboxylic group content and *** results revealed that autohydrolysis pretreatment resulted in a higher hemicelluloses extraction in *** contrast,the pulping yield of unpretreated samples was higher for ***,and the soda-AQ pulps from this species exhibited better delignification than the autohydrolysis-pretreated *** crystallinity index values of the obtained pulps were high(>80%),and the alpha-cellulose contents were *** viscosities of the aqueous nanocellulose suspensions were higher for the nanocellulose solutions obtained from the unpretreated soda-AQ ***,nanocellulose from *** unpretreated soda-AQ pulps had a higher rate of carboxylic *** results of this work are significant in assessing the potential of both bamboo species as a source of high-value products within the biorefinery framework because the viscosities of the aqueous nanocellulose suspensions depend on the size and shape of *** has significant importance for industrial unit operations and potential applications.

关键词： Natural fiber Guadua angustifolia Guadua trinii soda-anthraquinone pulp nanocellulose