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non-linear modeling of kinetic and equilibrium data for the adsorption of hexavalent chromium by carbon nanomaterials:Dimension and functionalization

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Chinese Journal of Chemical Engineering 2019年第4期27卷 912-919页

作者： Miguel de la Luz-Asunción Eduardo E.Pérez-Ramírez Ana L.Martínez-Hernández Victor M.Castano Víctor Sánchez-Mendieta Carlos Velasco-santos Facultad de Quimica Universidad Autonoma del Estado de Mexico Km. 12 de la carretera Toluca-Atlacomulco C.P. 50200 San Cayetano Toluca Estado de Mexico Mexico Tecnologico nacional de Mexico-Instituto Tecnologico de Queretaro Division de Estudios de Posgrado e Investigacion Av. Tecnologico s/n esq. GraL Mariano Escobedo Col. Centro Historico C.P. 76000 Santiago de Queretaro Queretaro Mexico Centro de Fisica Aplicada y Tecnologia Avanzada Universidad Nacional Autonoma de Mexico Boulevard Juriquilla 3001 Queretaro 76230 Mexico

The adsorption capacities for the removal of hexavalent chromium from aqueous solutions by six carbon nanomaterials have been evaluated. Single-walled and multi-walled carbon nanotubes as received and after oxidation treatment, graphene oxide and reduced graphene oxide are the materials with different dimension and functionalization compared in this research. Carbon nanotubes have been modified using hydrogen peroxide as oxidizing agent under microwave radiation. The oxidation treatment on carbon nanotubes has a positive effect increasing the adsorbent–adsorbate interaction. Rate-controlling mechanisms and equilibrium data are analyzed using non-linear models. non-linear method is proposed as the most suitable method for determining the kinetic and equilibrium parameters. The values of adsorption energy(E) obtained from the Dubinin–Radushkevich isotherm,have been found around 0.371 and 0.870 k J·mol-1, indicating physical adsorption. Therefore, the pseudo-second order model represents better the kinetic experimental data. The results show that the Langmuir isotherm provides a slightly better fit to the experimental data compared with the Freundlich isotherm, indicating homogeneous distribution of active sites on carbon nanomaterials and monolayer adsorption. The separation factors RLare found in the range of 0–1, suggesting that the adsorption process is suitable for all adsorbents. The mechanisms for hexavalent chromium removal have been proposed as electrostatic interactions and hydrogen bonding.

关键词： Carbon nanotubes Graphene Adsorption Hexavalent chromium Kinetic

Validation of CFD-deM simulation of a liquid-solid fluidized bed by dynamic analysis of time series

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Particuology 2022年第9期20卷 75-87页

作者： Julia Picabea Mauricio Maestri Miryan Cassanello Gabriel Salierno Cataldo de Blasio María Angélica Cardona Daniel Hojman Héctor Somacal departamento de Industrias Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresCiudad UniversitariaIntendente Güiraldes 2160C1428EGABuenos AiresArgentina COnICET-universidad de Buenos Aires Instituto de Tecnología de Alimentos y Procesos Químicos-ITAPROQCiudad UniversitariaIntendente Güiraldes 2160 C1428EGABuenos AiresArgentina Faculty of Science and Engineering Abo Akademi UniversityRantakatu 265100 VaasaFinland Laboratorio de Diagnósticos por Radiaciones Dep.Física ExperimentalComisión Nacional de Energía AtómicaBKNA1650 San MartínBuenos AiresArgentina COnICET C1033AAJ Buenos AiresArgentina Escuela de Ciencia y Tecnología Universidad de San MartínBKNA 1650 San MartínBuenos AiresArgentina

Liquid-solid fluidized beds(LSFB)modeling validation is crucial for establishing design rules and monitor-ing ***,it generally relies on comparing global variables,which overlook dynamic features that influence reaction *** work aims to implement time series analysis tools to compare Radioactive Particle Tracking data with a simulation consisting of Computational Fluid Dynamics cou-pled with Discrete-Element *** have been performed in a pilot-scale LSFB of calcium alginate spheres fluidized with a calcium chloride *** Diks'test indicates that the simulation can capture the LSFB *** also allows diagnosing flow regime transitions from the *** of solid dispersion coefficients and mixing times predicted by the simulation are in good agreement with the experiments.

关键词： Liquid-solid fluidization CFD-deM Dynamic comparison Radioactive particle tracking

Repellent and Insecticidal Activity of naphthoquinones from the Heartwood of Tectona grandis on Incisitermes marginipennis(Latreille)

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Phyton-International Journal of Experimental Botany 2023年第7期92卷 2165-2181页

作者： Crisanto Velázquez-Becerra Gu Yen Ambriz-Ortiz Rafael Torres-Martínez Mauro Manuel Martínez-Pacheco Facultad de Ingeniería en Tecnología de la Madera Universidad Michoacana de San Nicolás de HidalgoMoreliaMéxico Escuela nacional de Estudios Superiores Unidad MoreliaMoreliaMéxico Instituto de Investigaciones Químico-Biológicas Universidad Michoacana de San Nicolás de HidalgoMoreliaMéxico

Wood is a lignocellulosic material that,because of its organic nature,is a source of nutrients for bacteria,fungi,and *** marginipennis(Latreille)is an interesting dry wood-boring *** it is an extremely destructive pest,difficult to control due to its cryptic lifestyle,and for its role in the biogeochemical cycle of carbon and other elements;it is a fundamental *** use of less toxic and eco-friendly substances is important for protecting domestic,cultural,and historical heritage made of wood or lignocellulosic *** aim of this study was to evaluate the biological activity of various naphthoquinones extracted from the heartwood of *** on ***,heartwood flour was used for Soxhlet-type extractions to isolate and characterize the heartwood compounds by thin-layer *** identify the heartwood compounds,nuclear magnetic resonance and gas chromatography coupled to a mass spectrometer were *** information obtained was supported using the Interactive Spectroscopy *** identified heartwood compounds were lapachol,tectoquinone,deoxylapachol,dehydro-α-lapachone,tectol and *** nymphal termites of *** as a biological model,the isolated and identified molecules were under three different tests(repellent,insecticide and protective)and their biological activity was individually *** results showed that the molecules obtained have a repellent-protective effect against ***,although not in all cases,these molecules have high percentages of mortality and decreased the weight loss of the treated material exposed to ***.

关键词： naphthoquinones dry wood termite Incisitermes marginipennis wood preservatives

Optimal diet strategy of a large-bodied psittacine: food resource abundance and nutritional content enable facultative dietary specialization by the Military Macaw

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Avian Research 2019年第4期10卷 469-477页

作者： Sylvia Margarita de la Parra‑Martinez Luis Guillermo Munoz‑Lacy Alejandro Salinas‑Melgoza Katherine Renton departamento de Ciencias Biologicas Centro Universitario de la CostaUniversidad de GuadalajaraAv.Universidad No.203Delegacion IxtapaC.P.48280 Puerto VallartaJaliscoMexico Comision nacional Para el Conocimiento y Uso para la Biodiversidad Liga Periferico‑Insurgentes Sur 4903Delegacion Tlalpan14010 Mexico CityMexico Facultad de Biologia Universidad Michoacana de San Nicolas de HidalgoCiudad UniversitariaMoreliaMichoacanMexico Estacion de Biologia Chamela Instituto de BiologiaUniversidad Nacional Autonoma de MexicoApartado Postal 21San Patricio‑MelaqueJaliscoMexico

Background:Dietary specialization should arise when there is a relatively high abundance of a particular resource,where animals may select food items to obtain an optimal diet that maximizes energy ***‑bodied psittacines frequently exhibit a narrow dietary niche with specific habitat use,but few studies have determined whether psittacines select food resources,and how this influences habitat ***:We established fruiting phenology transects to evaluate food resource availability for the large‑bodied Military Macaw(Ara militaris)in semi‑deciduous,deciduous,and pine‑oak forest at two sites along the coast of Jalisco,during the dry season when macaws are *** also determined Military Macaw diet by observations of foraging macaws along transect routes,and conducted bromatological analysis of the nutritional content of the most consumed ***:Military Macaws used six plant species as food items during the dry season,and had a narrow dietary niche(Levins’B=0.28),with 56%of foraging macaws consuming the seeds of Hura *** food resources were recorded in pine‑oak forest during the dry season,with food resources and foraging by macaws concentrated in tropical deciduous and semi‑deciduous forest,where *** was the most abundant fruiting tree *** considering the proportional availability of food resources,we determined a broad Hurlbert dietary niche breadth of H=0.67,indicating that Military Macaws consumed food resources according to their ***,the seeds of *** were an important source of protein,carbohydrates,minerals and moisture,and the hard fruitcasing means that these seeds are exclusively available for ***:By concentrating their diet on the most abundant resources,Military Macaws may increase foraging efficiency in the dry *** high nutrient content also means that concentrating the diet on seeds of *** may be an optimal foraging strategy for Military Macaws

关键词： Ara militaris Bromatological analysis Diet composition Food resource selection Fruiting phenology Hura polyandra Psittacidae Tropical dry forest

Transcriptional Programs Related to Phytochrome A Function in Arabidopsis Seed Germination

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Molecular Plant 2013年第4期6卷 1261-1273页

作者： Silvia E. Ibarra Gabriela Auge Rodolfo A. sanchez Javier F. Botto IFEVA Facultad de Agronomfa Universidad de Buenos Aires y Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. San Martin 4453 C1417DSECiudad de Buenos Aires Argentina

In Arabidopsis seeds, germination is promoted only by phytochromes, principally phytochrome B （phyB） and phytochrome A （phyA）. despite the abundant information concerning the molecular basis of phyB signaling downstream of PIF1/PIL5, the signaling network inducing germination by phyA is poorly known. Here, we describe the influence of phyA on the transcriptome of Arabidopsis seeds when germination is induced by a far-red （FR） pulse. The expression of 11% of the genome was significantly regulated by phyA. Most of the genes were up-regulated and the changes noted late （i.e. 5 h after a FR pulse）, whereas changes in down-regulated genes were more abundant earlier （i.e. 0.5 h after a FR pulse）. Auxin- and GA-associated elements were overrepresented in the genes that were modified by phyA. A significant number of genes whose expression was affected by phyA had not been previously reported to be dependent on PIL5. Among them, homozygotic mutant seeds of MYB66, a SAUR-like protein, PIn7, and GASA4 showed an impaired promo- tion of germination by phyA. natural variation at the transcriptional level was found in early signaling and GA metabolic genes, but not in ABA metabolic and expansin genes between Columbia and Landsberg erecta accessions. Although phyA and phyB/PIL5 signaling pathways share some molecular components, our data suggest that phyA signaling is partially independent of PIL5 when germination is promoted by very low fluences of light.

关键词： transcriptome germination light Arabidopsis seeds PIF1/PIL5 phytochrome A (phyA) phytochrome B (phyB).

Petrogenesis of Quebrada de la Mina and Altar north porphyries (Cordillera of san Juan, Argentina): Crustal assimilation and metallogenic implications

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Geoscience Frontiers 2017年第5期8卷 1135-1159页

作者： Laura Maydagán Marta Franchini Massimo Chiaradia Verónica Bouhier noelia Di Giuseppe Roger Rey Luis Dimieri Centro Patagónico de Estudios Metalogenéticos-COnICET Argentina InGEOSUR-COnICET Departamento de Geología Universidad Nacional del Sur San Juan 670 8000 Bahía Blanca Argentina Instituto de Investigación en Paleobiología y Geología Universidad Nacional de Río Negro Av. Roca 1242 8332 Roca Argentina departamento de Geología y Petróleo Facultad de Ingeniería Universidad Nacional del Comahue Buenos Aires 1400 8300 Neuquén Argentina Section of Earth and Environmental Sciences University of Geneva Switzerland Minera Peregrine Argentina S.A Santa Fe (Oeste) 117 Piso 4B Edificio Derby Ciudad San Juan Argentina

We investigate the geology of Altar north(Cu-Au) and Quebrada de la Mina(Au) porphyry deposits located in san Juan Province(Argentina), close to the large Altar porphyry copper deposit(995 Mt,0.35% Cu, 0.083 g/t Au), to present constraints on the magmatic processes that occurred in the parental magma chambers of these magmatic-hydrothermal systems. Altar north deposit comprises a plagioclase-amphibole-phyric dacite intrusion(Altar north barren porphyry) and a plagioclaseamphibole-biotite-phyric dacite stock(Altar north mineralized porphyry, 11.98 ± 0.19 Ma). In Quebrada de la Mina, a plagioclase-amphibole-biotite-quartz-phyric dacite stock(QDM porphyry,11.91±0.33 Ma) crops out. High Sr/Y ratios(92-142) and amphibole compositions of Altar north barren and QDM porphyries reflect high magmatic oxidation states(fO_2= nnO+1.1 to+1.6) and high fH_2O conditions in their magmas. Zones and rims enriched in anorthite(An_(37-48))), SrO(0.22-0.33 wt.%)and FeO(0.21-0.37 wt.%) in plagioclase phenocrysts are evidences of magmatic recharge processes in the magma chambers. Altar north and Quebrada de la Mina intrusions have relatively homogeneous isotopic compositions(^(87)Sr/^(86)Sr_(t)= 0.70450-0.70466, ε_(nD)(t) = +0.2 to +1.2) consistent with mixed mantle and crust contributions in their magmas. Higher Pb isotopes ratios(^(207)Pb/^(204)Pb=15.6276-15.6294) of these intrusions compared to other porphyries of the district, reflect an increase in the assimilation of high radiogenic Pb components in the magmas. Ages of zircon xenocrysts(297,210,204,69 Ma) revealed that the magmas have experienced assimilation of Miocene, Cretaceous, Triassic and Carboniferous crustal *** that precipitated sulfides in the Altar deposit may have remobilized Pb from the host rocks, as indicated by the ore minerals being more radiogenic(207Pb/204 Pb = 15.6243-15.6269) than their host intrusions. Au/Cu ratio in Altar porphyries(average Au/Cu ratio of 0.14 ×10^(-4)by weight in Altar Central)is hig

关键词： Porphyry High sulfidation epithermal Magmatic recharge Radiogenic isotopes Crustal assimilation Argentinian Andes

On Boolean Lattices of Module Classes

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Algebra Colloquium 2018年第2期25卷 285-294页

作者： Alejandro Alvarado-Garcia Cesar Cejudo-Castilla Hugo Alberto Rincon-Mejia Ivan Fernando Vilchis-Montalvo Manuel Gerardo Zorrilla-noriega Facultad de Ciencias Universidad Nacional Autonoma de Mexico Circuito Exterior C.U. C.P. 04510 Ciudad de Mexico Mexico Facultad de Ciencias Fisico Matemdticas Benemerita Universidad Autonoma de Puebla Av. San Claudio y 18 Sur Col. San Manuel Ciudad Universitaria C.P. 72570 Puebla Mexico Facultad de Ciencias Universidad Nacional Autonoma de Mexico Circuito Exterior C.U. C.P. 04510 Ciudad de Mdxico Mdxico Facultad de Ciencias Ffsico Matematicas Benemerita Universidad Autonoma de Puebla Av. San Claudio y 18 Sur Coi. San Manuel Ciudad Universitaria C.P. 72570 Puebla Mexico

Some properties of and relations between several （big） lattices of module classes are used in this paper to obtain information about the ring over which modules are taken. The authors reach characterizations of triv... 详细信息

关键词： torsion theories hereditary pretorsion classes natural classes conaturalclasses boolean lattice

Electrocardiographic markers of cardiac resynchronization therapy response:delayed time to intrinsicoid deflection onset in lateral leads

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Journal of Geriatric Cardiology 2022年第1期19卷 21-30页

作者： Rubén KA Tapia-Orihuela S Michael Gharacholou Samuel J Asirvatham Freddy del-Carpio Munoz department of Medicine Universidad Nacional Mayor de San MarcosFacultad de Medicina de San FernandoLimaPeru department of Cardiovascular Diseases Mayo ClinicJacksonvilleFLUSA department of Cardiovascular Diseases Mayo ClinicRochesterMNUSA

Cardiac resynchronization therapy(CRT)has emerged as an important intervention for patients with heart failure(HF)with reduced ejection fraction and delayed ventricular *** these patients,CRT has demonstrated to improve quality of life,promote reverse left ventricular(LV)remodeling,reduce HF hospitalizations,and extend ***,despite advancements in our understanding of CRT,a significant number of patients do not respond to this *** invasive and non-invasive parameters have been assessed to predict response to CRT,but the electrocardiogram(ECG)has remained as the prevailing screening method albeit with ***,an accurate,simple,and reproducible ECG marker or set of markers would dramatically overcome the current *** describe the clinical utility of an old ECG parameter that can estimate ventricular activation delay:the onset to intrinsicoid deflection(ID).Based on the concept of direct measurement of ventricular activation time(intrinsic deflection onset),time to ID onset measures on the surface ECG the time that the electrical activation time takes to reach the area subtended by the corresponding surface ECG *** on this principle,the time to ID on the lateral leads can estimate the delay activation to the lateral LV wall and can be used as a predictor for CRT response,particularly in patients with non-specific intraventricular conduction delay or in patients with left bundle branch block and QRSnt the current evidence and potential use of this ECG parameter to estimate LV activation and predict CRT response.

关键词： deflection intrinsic synchronization

Effect of light on seed germination and seedling shape of succulent species from mexico

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Journal of Plant Ecology 2016年第2期9卷 174-179页

作者： Joel Flores Claudia González-Salvatierra Enrique Jurado División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa de San José2055Col.Lomas4SecciónSan Luis PotosíSan Luis Potosí78216México Facultad de Ciencias Forestales Universidad Autónoma de Nuevo LeónCarretera Nacionalkm 145LinaresN.L.67700México

Aims Light requirements for cactus seed germination have been considered to be associated with their adult plant height and seed mass,but this has not been thoroughly studied for other succulent *** order to understand seed photosensitivity from desert species belonging to Asparagaceae(subfamily Agavoideae)and Cactaceae,we performed a germination experiment with and without light for 12 species and 2 varieties from 1 species from the Southern Chihuahuan *** also determined if adult growth is totally determined by seedling‘growth form’in *** We performed a germination experiment using light and darkness for 13 species from Southern Chihuahuan desert:10 rosette species(Asparagaceae),as well as 1 globose,1 columnar and 2 varieties from 1 depressed-globose species(Cactaceae).The response variables were seed germination percentage and relative light germination(RLG).In addition,in order to determine if adult-globose cacti could have cylindrical seedlings,we calculated the shape index(height/width ratio)for Coryphanta clavata and Mammillaria *** Findings All species were considered neutral *** species had similar seed germination in both light and dark conditions,and three taxa(*** and the two varieties of Ferocactus latispinus)showed higher germination with light than without *** salmiana,*** and the two varieties of *** had higher RLG than the other *** mass was an important factor because with higher seed mass there was lower dependence to *** findings support the hypothesis that small seed mass and light requirements have coevolved as an adaptation to ensure *** adult-globose cactus species,***,and one adult-columnar species,***,had small seeds and neutral *** from these two species exposed to light were cylindrical and those under darkness conditions were *** seeds from this species are able to germinate in

关键词： Asparagaceae Cactaceae Chihuahuan desert photoblasticism seed germination succulent plants