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Determination of the Sound Absorption Capacity of Hydraulic Concrete Mixtures Added with Waste Tire Rubber

丛书名： Lecture notes in Computer Science 2771

2004年

作者： Rubén Hinojosa Chapel (auth.) Uffe Kock Wiil (eds.)

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Journal of Minerals and Materials Characterization and Engineering 2023年第5期11卷 197-211页

作者： María Luisa Moguel pacheco Fermín Castillo Mejía Yamilet Rodríguez Lazcano Andrés Aguilar negrete Arturo Molina Ocampo Jesús Mario Colín de la Cruz Universidad Autónoma del Estado de Morelos Facultad de Ciencias Químicas e Ingeniería Programa Educativo de Ingeniería Industrial Cuernavaca México Universidad nacional Autónoma de México Instituto de Ciencias Físicas Cuernavaca México Universidad Autónoma de nayarit Unidad Académica de Ciencias Básicas e Ingeniería Tepic México Universidad Autónoma del Estado de Morelos Centro de Investigación en Ingeniería y Ciencias Aplicadas Cuernavaca México

There are different types of pollutants that are harmful to the environment, including smog, chemicals that are dumped into rivers, scrap tires, etc. The latter have the particularity that it is not possible to recycle them to manufacture new tires. In the present work, hydraulic concrete plates added with waste tire rubber were manufactured to modify their sound absorption capacity. It was found that the rubber additions produce changes in the density of the material and in the sound absorption capacity. When the material is exposed to high-frequency sounds that correspond to high-pitched sounds, its absorption capacity increases. On the contrary, when the test frequency is low, that is, bass sounds, the sound absorption capacity decreases. The results obtained in this work suggest that the proposed mixtures are suitable for the possible manufacture of acoustic insulating shields.

关键词： Hydraulic Concrete Waste Tire Rubber Sound Absorption noise Reduction Coefficient

Cognitive disorder and dementia in type 2 diabetes mellitus

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World Journal of Diabetes 2022年第4期13卷 319-337页

作者： Genaro G Ortiz Miguel Huerta Héctor A González-Usigli Erandis D Torres-Sánchez Daniela LC Delgado-Lara Fermín P pacheco-Moisés Mario A Mireles-Ramírez Blanca MG Torres-Mendoza Roxana I Moreno-Cih Irma E Velázquez-Brizuela Department of Philosophical and Methodological Disciplines University Health Sciences CenterUniversity of GuadalajaraGuadalajara 44340JaliscoMexico Department of neurology Movement Disorders ClinicSub-Specialty Medical UnitNational Western Medical CenterMexican Social Security Institute(IMSS)Guadalajara 44340JaliscoMexico University Biomedical Research Center University of ColimaColima 28040Mexico Department of Medical and Life Sciences University Center of‘La Ciénega’University of GuadalajaraOcotlán 47810JaliscoMexico Department of Chemistry University Center of Exact Sciences and EngineeringUniversity of GuadalajaraGuadalajara 44340JaliscoMexico Division of neurosciences Western Biomedical Research CenterMexican Social Security Institute(IMSS)Guadalajara 44340JaliscoMexico Gerontology Postgraduate Program Public Health DepartmentUniversity Health Sciences CenterUniversity of GuadalajaraGuadalajara 44340JaliscoMexico

Insulin,a key pleiotropic hormone,regulates metabolism through several signaling pathways in target tissues including skeletal muscle,liver,and *** the brain,insulin modulates learning and memory,and impaired insulin signaling is associated with metabolic dysregulation and neurodegenerative *** the receptor level,in aging and Alzheimer’s disease(AD)models,the amount of insulin receptors and their functions are *** and animal model studies suggest that memory improvements are due to changes in insulin ***,diabetes mellitus(DM)and insulin resistance are associated with age-related cognitive decline,increased levels ofβ-amyloid peptide,phosphorylation of tau protein;oxidative stress,pro-inflammatory cytokine production and dyslipidemia. Recent evidence shows that deleting brain insulin receptors leads to mildobesity and insulin resistance without influencing brain size and apoptosis ***, deleting insulin-like growth factor 1 receptor (IGF-1R) affects brain size anddevelopment, and contributes to behavior changes. Insulin is synthesized locally in the brain andis released from the neurons. Here, we reviewed proposed pathophysiological hypotheses toexplain increased risk of dementia in the presence of DM. Regardless of the exact sequence ofevents leading to neurodegeneration, there is strong evidence that mitochondrial dysfunctionplays a key role in AD and DM. A triple transgenic mouse model of AD showed mitochondrialdysfunction, oxidative stress, and loss of synaptic integrity. These alterations are comparable tothose induced in wild-type mice treated with sucrose, which is consistent with the proposal thatmitochondrial alterations are associated with DM and contribute to AD development. Alterationsin insulin/IGF-1 signaling in DM could lead to mitochondrial dysfunction and low antioxidantcapacity of the cell. Thus, insulin/IGF-1 signaling is important for increased neural processing andsystemic metabolism, a

关键词： Alzheimer´s disease Diabetes mellitus Insulin Vascular dementia Cognitive decline

基于氯化胆碱的低共熔体系在Au上电沉积无枝晶Zn

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Transactions of nonferrous Metals Society of China 2024年第7期34卷 2367-2380页

作者： Vesna S.CVETKOVIĆ nebojša D.nIKOLIĆ Tanja S.BARUDŽIJA Silvana B.DIMITRIJEVIĆ Jovan n.JOVIĆEVIĆ Department of Electrochemistry Institute of ChemistryTechnology and MetallurgyUniversity of BelgradeNjegoševa 1211000 BelgradeSerbia Institute for nuclear Sciences Vinča University of BelgradeP.O.Box 52211001 BelgradeSerbia Mining and Metallurgy Institute Zeleni bulevar 3519210 BorSerbia

以氯化胆碱和乙二醇混合液为低共熔溶剂,不使用其他添加剂,电化学沉积无枝晶Zn/Au合金。在不同的Zn(Ⅱ)浓度下,采用恒电位电沉积法在相对较低的Zn电沉积过电位下进行电沉积。通过循环伏安法(CV)和计时安培法(CA)揭示Zn电沉积的电化学机... 详细信息

以氯化胆碱和乙二醇混合液为低共熔溶剂,不使用其他添加剂,电化学沉积无枝晶Zn/Au合金。在不同的Zn(Ⅱ)浓度下,采用恒电位电沉积法在相对较低的Zn电沉积过电位下进行电沉积。通过循环伏安法(CV)和计时安培法(CA)揭示Zn电沉积的电化学机理。采用扫描电子显微镜和X射线衍射分析(XRD)对沉积层的形貌和结构进行表征,并用能谱仪对沉积层进行元素分析。CV结果表明,Zn的电沉积始于Zn欠电位沉积区,并一直持续到Zn过电位沉积(OPD)区。随着Zn(Ⅱ)浓度的增加,Zn/Zn(Ⅱ)电偶的沉积电位向更高的正值偏移。CA分析表明,在Zn的OPD区开始三维渐进形核,随后形成三维生长。形貌分析表明,电沉积始于致密Zn岛的形成,随后形成无枝晶Zn/Au合金。XRD分析表明,其物相为金属Zn、立方AuZn3和Au Zn金属间化合物。

关键词：锌电沉积低共熔溶剂锌金合金形貌结构

The Igarape Weir decelerated transport of contaminated sediment in the Paraopeba River after the failure of the B1 tailings dam(Brumadinho)

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International Journal of Sediment Research 2023年第5期38卷 673-697页

作者： Daniela Patrícia Salgado Terêncio Fernando António Leal pacheco Renato Farias do Valle Junior Maytê Maria Abreu Pires de Melo Silva Teresa Cristina Tarlé Pissarra Marília Carvalho de Melo Carlos Alberto Valera Luís Filipe Sanches Fernandes Inov4Agro/Centro de Investiga??o e Tecnologias Agroambientais e Biológicas Universidade de Trás-os-Montes e Alto Douro Centro de Química de Vila Real Universidade de Trás-os-Montes e Alto Douro Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista(UNESP) Via de Acesso Prof.Paulo Donato Castellane Instituto Federal do Triangulo Mineiro Campus Uberaba Laboratório de Geoprossessamento 5. Secretaria de Estado de Meio Ambiente e Desenvolvimento Sustentável Cidade Administrativa do Estado de Minas Gerais Rodovia Jo?o Paulo II 6. Coordenadoria Regional das Promotorias de Justi?a do Meio Ambiente das Bacias dos Rios Paranaíba e Baixo Rio Grande Rua Coronel Ant?nio Rios

The B1 dam of Co rrego do Feij～ao Mine, owned by Vale, S.A. mining company and located on the FerroCarv～ao stream, collapsed and injected 2.8 Mm3of clayey, silty, and sandy iron-and manganese-rich tailings into the Paraopeba River(Minas Gerais state, Brazil). The accident occurred on 25 January2019 and the tailings have been co-transported with coarser natural sediment since then, being partly trapped in the Igarape Weir reservoir located on the Paraopeba River nearly 45 km downstream the injection point. The general purpose of the current study was to model suspended sediment transport in the vicinity of the Igarape Weir aiming to assess the concomitant barrier effect imposed by this ***, the spatial distributions of suspended clay, silt, and very fine-grained sand fractions(CSS) of sediment were mapped around the Igarape Weir under low-flow(16 m3/s) and high-flow(5 to 10,000years return period stream discharge; 699—2,699 m3/s) regimes, using RiverFlow2D as the modelling tool. The concentrations of the various grain materials in the upstream and downstream sectors were quantified linking the barrier effect to concentration reductions in the direction of stream flow. It was also a study goal to calculate differences of iron and manganese concentrations in the sediment + tailings mixtures along the Paraopeba River. The study results showed reductions in the CSS between 6.6% and18%, from upstream to downstream of the Igarape Weir, related with backwater effects, free and submerged hydraulic jumps, bank sedimentation in periods of high flow, and streambed sedimentation controlled by channel sinuosity and tailings density. These reductions were accompanied by drops in the concentrations of iron and manganese present in the clay and silt fractions, which varied between 6% and42% under low flows and between 16% and 44% under high flows. Bank sedimentation was viewed as a potential threat to the riparian vegetation in the long-term. Dredging is the poten

关键词： Sediment transport Tailings dam break Metal contamination Hydrodynamic modelling RiverFlow2D Ratio concentration analysis

Effect of proteases on water-soluble and fat-soluble aroma precursors of goat visceras protein hydrolysate

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Food Bioscience 2022年第3期47卷 975-985页

作者： Ana Rita Ribeiro de Araújo Cordeiro Lorena Lucena de Medeiros Lary de Souza Olegário Leila Moreira de Carvalho Taliana Kenia Alencar Bezerra Maria Teresa Bertoldo pacheco Mércia de Sousa Galvão Marta Suely Madruga Post Graduate Program in Food Science and Technology Department of Food EngineeringTechnology CentreFederal University of ParaibaCampus I58051-900João PessoaParaíbaBrazil Food Technology Institute (ITAL).Science and Food Quality Center 13070-179CampinasSão PauloBrazil

This study investigated the action of proteolytic enzymes in the production of goat viscera hydrolysates,and their flavoring *** study focus the production of flavor precursor molecules and the formation of volatile compounds resulting from four hydrolysis treatments:HA-Alcalase®,HF-Flavourzyme®,Hn-neutrase®,and HFn-Flavourzyme® and neutrase®.The highest degree of hydrolysis (26.74%),number (23 volatiles) and concentration of volatile compounds (274.0 μg/L) were obtained with the action of *** main classes of volatile compounds identified in hydrolysates included acids,aldehydes,pyrazines,terpenes and Streacker *** acids,sugars and fatty acids were identified with higher concentrations in HF and HFn hydrolysates due to the low participation of these precursors in the formation of volatile ***,the use of Alcalase in the proteolysis of goat viscera stood out compared to other enzymes,providing impacting aroma compounds,such as pyrazines,for meat flavor.

关键词： Aroma precursors Flavoring Goat byproducts Proteases Enzymatic hydrolysates Volatile compounds

Pharmacokinetics of sildenafil in children with pulmonary arterial hypertension

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World Journal of Pediatrics 2017年第6期13卷 588-592页

作者： Hugo Juárez Olguín Hector Osnaya Martínez Carmen Flores Pérez Blanca Ramírez Mendiola Liliana Rivera Espinosa Juan Luis Chávez pacheco Janett Flores Pérez Ignacio Mora Maga(n)a Laboratory of Pharmacology National Institute of PediatricsMexico CityMexico Department of Pharmacology Faculty of MedicineNational Autonomous University of MexicoMexico CityMexico Service of Cardiology National Institute of PediatricsMexico CityMexico Laboratory of Pharmacology National Institute of PediatricsMexico CityMexico Subdirection of Teaching and Educational Programming National Institute of PediatricsMexico CityMexico

Background:Recently,sildenafil was introduced to treat pulmonary arterial hypertension (PAH);however,there are currently few studies on the pharmacokinetics of sildenalfil in ***,we aimed to carry out a pharmacokinetic study of sildenafil in children with PAH using a single ***:Twelve children diagnosed with PAH,consisting of with ten males and two females,were recruited for the study after obtaining written consent from their parents or *** samples were obtained predose and at 0.25,0.5,1,2,4,8 and 12 hours after the oral administration of 1 mg/kg of sildenafil using an extemporal pediatric formulation developed in our *** samples were analyzed using a previously validated high performance liquid chromatography ***:A pharmacokinetic analysis using the Winnonlin 3.1 program that considered the Akaike information criterion (AIC) for sdecting a more adjustable model was *** following pharmacokinetic parameters were obtained:maximal concentration (Cmax):366+179 ng/mL,time to maximal concentration:0.92±0.30 hours,elimination half-life (t1/2):2.41±1.18 hours,total clearance (CLto/F):5.85±2.81 L/hour,volume of distribution (Vd/F):20.13±14.5 L,absorption rate constants (Ka):0.343 hour-1,elimination rate (Ke):0.35 hour-1,area under curve from zero to infinity:2061±618 ng/mL/*** data of all patients adjusted to the model of one compartment were corroborated using ***:The parameters Ka,Ke and t1/2 were found to be similar to those reported in adults;however,the values of Cmax and Vd/F were significantly *** on these findings,we propose that treatment regimen of sildenafil be adjusted in children with PAH.

关键词： pharmacokinetics pulmonary arterial hypertension sildenafil

nonuniform Sampling: Theory and Practice 1

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Inhibitory Effect of n,n-Dimethylhexadecylamine on the Growth of White-Rot Fungus Trametes versicolor(L.)in Wood

丛书名： Information Technology: Transmission, Processing, and Storage

2001年

作者： F. Marvasti (auth.) Farokh Marvasti (eds.)

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Phyton-International Journal of Experimental Botany 2021年第1期90卷 193-206页

作者： Wilber Montejo-Mayo Eduardo Días-Rivera Mauro Martínez-pacheco Abril Munro-Rojas Enrique Ambriz-Parra Crisanto Velázquez-Becerra Universidad Michoacana de San nicolás de Hidalgo Facultad de Ingeniería en Tecnología de la MaderaCiudad UniversitariaMorelia58030México Instituto de Investigaciones Químico-Biológicas Universidad Michoacana de San Nicolás de HidalgoCiudad UniversitariaMorelia58030México

Wood is an organic material that is a source of carbon of organisms called Wood-decay fungi,and to preserve the wood,various toxic compounds to man and the environment have been *** analyze the effect of n,nDimethylhexadecylamine(DMHDA)on wood attacked by the rotting fungus Trametes versicolor *** used an in vitro system to expose the fungus *** to different concentrations of the DMHDA(50,150 and 450µM).We quantified the diameter of mycelial growth and laccase activity,also,under these experimental conditions we studied morphological details of the organisms using different scanning equipment including scanning electron *** growth of *** exposed to DMHDA for 60 days,showed a concentration-dependent dose behavior,also,the electron microscopy analysis revealed that the morphology and mycelial density was affected by the DMHDA,showing a formation of atypical morphological and thickener ***,the pieces of wood treated with DMHDA and exposed to the fungus had a lower mass loss,after a period of 60 days of exposure,the values obtained were 0.7,1.0 and 0.5 g of mass lost for the control,LoC and LoDMHDA treatments ***-rot fungi have represented economic losses worldwide,the strategies used have been supported by toxic compounds for the *** DMHDA both in the Petri dish system and as a wood preservative was shown to significantly inhibit the growth of ***.

关键词： Wood-decay fungi n,n-dimethylhexadecylamine wood preservative

Geographic Information Technologies for the Study of Mass Wasting Hazards

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International Journal of Geosciences 2014年第5期5卷 519-526页

作者： Henry pacheco Carlos Suárez Universidad Pedagógica Experimental Libertador Instituto Pedagógico de Caracas Departamento de Ciencias de La Tierra. Centro de Investigación “Estudios del Medio Físico Venezolano” Venezuela

The purpose of the research was to obtain the mass wasting hazard map for the state of Vargas, central coast of Venezuela, using GIS technology. The work was developed through the heuristic method with the generation of thematic digital maps, univariate statistical treatment, weighting of each variable and quantifying the relationship of each parameter unit regarding mass wasting processes. The algorithm designed to perform map algebra was designed using the variables: surface geology, slope, slope orientation, terrain curvature, moisture topographic index, power index surface flow rate and capacity sediment transport and the rate normalized difference vegetation. The results show a distribution of landslide hazard with the highest values in the west central part of Vargas state, where the dominant lithology is incompetent, and combined with topographic elements, determining high instability, meanwhile the lower hazard areas were found in specific areas such as the middle watershed areas east of the state. The calibration of this model shows a reliability of 80%, so it is highly advisable to use the information generated in this work by governmental and non-governmental organizations in the planning, management and use of land.

关键词： Mass Wasting Hazards GIS Vargas State Venezuela