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Water Quality Assessment of Jose Antonio Alzate Dam, the Lerma River and Its Tributaries in the State of mexico, mexico

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Journal of Environmental Protection 2012年第8期3卷 878-888页

作者： Icela Barceló-Quintal Edgar López-galván Hugo Solís-Correa Eloisa Domínguez-mariani Sergio Gómez-Salazar área de Química y Fisicoquímica Ambiental Depto de Ciencias Básicas División de Ciencias Básicas e Ingeniería UAM-Azcapot- zalco Ciudad de México D.F. México departamento de Ingeniería Química Universidad de Guadalajara. Centro Universitario de Ciencias Exactas e Ingenierías Guadalajara Jalisco México

Water quality was evaluated at sites of the Jose Antonio Alzate Dam, the rivers Lerma, Tejalpa and Temoaya in the State of mexico, mexico. The variables measured included pH, conductivity, temperature, dissolved oxygen (Do), ammonia, nitrates, sulfates, sulfides and metal concentrations (Cu and Pb). Chemical speciation for dissolved metals in the aqueous phase was obtained using measured concentrations and the software mINEQL+ (4.5);metal partition coefficients was also obtained using dissolved and particulate concentrations of metals. Hydraulic behavior of the studied water bodies was investigated and the fate of Cu and Pb ions was simulated. The simulation results indicate that the Lerma River provides the majority of organic matter and metal contaminants as a result of a poor oxygen saturation velocity, and showed a slight improvement when the Lerma River is subjected to its tributaries Tejalapa and Temoaya Rivers. Under the reducing conditions predominating along the dam and from the results of aqueous phase chemical speciation, it was found that sulfide metal-associated species are the ones that predominate. It was demonstrated that in general, the rivers Tejalapa and Temoaya presented the best water quality. The Lerma River oxygen saturation improves after the rainy season, but it worsens during the dry season. Due to irregular topography, the small slope prevailing in the Lerma River, and the almost nonexisting water flow, zones with different characteristics are formed within the dam. The sedimentation contributes in the generation of local eddies causing the existence of a small diffusive flow. The order of partition coefficient was Pb > Cu. Cu presented the highest risk levels in the dissolved phase.

关键词： Water Quality Copper Lead Partition Coefficients Chemical Speciation

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Solvent- and Catalyst-Free microwave-Assisted decarboxylation of malonic Acid derivatives

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Green and Sustainable Chemistry 2017年第4期7卷 270-280页

作者： Fanny Araceli Cabrera-Rivera Luis Gabriel Hernández-Vázquez Patricia Flores-Sánchez maria Durán-galván Jaime Escalante The Center of Chemical Research UAEM Cuernavaca México SIGNA Civac S. A. de C. V. Jiutepec México

It has been found that microwave assisted decarboxylation of malonic acid derivatives can be achieved under solvent-free and catalyst free conditions. This new method produces the corresponding carboxylic acid in a pure manner and with a high yield in a very short reaction time: 3 - 10 min. In general terms, the condition under which this reaction is carried out accelerates the decarboxylation significantly of a series of disubstituted malonic acid derivatives, and makes this new process efficient, easy and environmentally friendly.

关键词： microwave decarboxylation malonic Acid derivatives Solvent-Free Catalyst-Free Green Chemistry

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Cholinergic neuromuscular junctions in Brachionus calyciflorus and Lecane quadridentata(Rotifera:monogononta)

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Journal of Coastal Life medicine 2014年第5期 376-381页

作者： Ignacio Alejandro Pérez-Legaspi Alma Lilián Guerrero-Barrera Iván Joségalván-mendoza JoséLuis Quintanar Roberto Rico-martínez Graduate Studies and Research Division Boca del Río Institute of TechnologyKm.12 Carr.Veracruz–Córdoba94290Boca del RíoVer.México morphology department Basic Sciences CenterAguascalientes Autonomous UniversityAve.Universidad 940Aguascalientes20100México Confocal microscopy Unit Experimental Services DepartmentCINVESTAV-ZacatencoNational Politechnic InstituteAve.Politécnico2508Zacatenco56000MéxicoD.F.México Pharmacology and Physiology department Aguascalientes Autonomous UniversityAve.Universidad 940Aguascalientes20100México Chemistry department Basic Sciences CenterAguascalientes Autonomous UniversityAve.Universidad 940Aguascalientes20100México

objective:To identify the presence of joint muscular and cholinergic systems in two freshwater rotifer species,Brachionus calyciflorus and Lecane ***:The muscle actin fibers were stained with phalloidin-linked fluorescent dye,and acetylcholine was detected with Amplex Red Acetylcholine/Acetylcholinesterase Assay Kit,and then confocal scanning laser microscopy was ***:The musculature of Brachionus calyciflorus showed a pattern similar to other species of the same genus,while that of Lecane quadridentata was different from other rotifer genera described *** cholinergic system was determined by co-localization of both muscles and acetylcholine labels in the whole rotifer,suggesting the presence of neuromuscular ***:The distribution pattern of muscular and acetylcholine systems showed considerable differences between the two species that might be related to different adaptations to particular ecological *** confirmation of a cholinergic system in rotifers contributes to the development of potential neuro-pharmacological and toxicological studies using rotifers as model organism.

关键词： Acetylcholine Co-localization Confocal microscopy F-actin Rotifer

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magnetic Properties of Chromium Dioxide Nanoparticles Produced by Thermal oxidation Technique

Magnetic Properties of Chromium Dioxide Nanoparticles Produc...

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2012 2nd International Conference on materials,mechatronics and Automation(ICmmA 2012)

作者： Roberto Baca Arroyo miguel galván Arellano Gabriel R.Paredes Rubio Ramón Pea Sierra department of Electronics National Polytechnic Institute México México department of Electrical Engineering CINVESTAV 07360 México México

We have synthesized chromium dioxide nanoparticles on chromium oxide thin-films using thermal oxidation technique in air atmosphere conditions. Raman spectroscopy revealed that thermally oxidized films exhibit a broad band attributed to magnons and estimated crystallite size distribution of the nanoparticles is from 5nm to 15nm by scanning electron microscopy. Dynamic magnetic properties of chromium dioxide nanoparticles have been studied using the experimental technique based on RF-resonant circuit at room temperature. The thermally oxidized films show anisotropy-exchange interaction behavior. From X-ray diffraction patterns a structural analysis of chromium oxide thin-films as a function of relative strains and average crystalline size demonstrate that both magnetic and elastic behavior are connected by magnetoelastic coupling.

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Evaluation of Two Highly Porous microcrystalline Biphasic Calcium Phosphate-Based Bone Grafts for Bone Regeneration: An Experimental Study in Rabbits

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Journal of materials Science and Chemical Engineering 2020年第6期8卷 8-30页

作者： miguel Ángel Garcés-Villalá Sergio David Rico Sergio Gustavo Nazar mariano Escudero-Pinel Víctor galván-Josa José Luis Calvo-Guirado department of Implant and Biomaterial Research Fundación Corazón de Jesús San Juan Argentina Facultad de matemática Astronomía y Física Universidad Nacional de Córdoba Córdoba Argentina department of oral Surgery and Implant dentistry Faculty of Health Sciences Universidad Católica San Antonio de Murcia Murcia Spain

A biphasic bone grafting biomaterial based on a mixture of calcium phosphates and beta-tricalcium phosphate (β-TCP) phases with high nanoporosity was synthesized. The synthesis route was based on calcium phosphate co... 详细信息

A biphasic bone grafting biomaterial based on a mixture of calcium phosphates and beta-tricalcium phosphate (m>βm>-TCP) phases with high nanoporosity was synthesized. The synthesis route was based on calcium phosphate composition and the incorporation of glycolic acid as a pore former, giving a material composed of 97% m>βm>-TCP and 3% calcium orthophosphates (CaPo4). Anm> im>m>m>m>n m>m>vitrom> study of the purity, microstructure, crystalline domain, and pores size for the material obtained was performed by SEm analysis as well as full structural characterization. The region of interest related to the surface was determined by the specific surface area measured with the BET method. m>In vivom> evaluation of bone response was performed by implanting the new low-cost biphasic manufacturing material synthesized in this work, which was compared with a biphasic material of similar chemical and microstructural composition existing in the commercial market and with higher cost called Synergy odontit® m>βm>-TCP. The materials were implanted separately into 5 mm diameter defects in the tibias of New Zealand White rabbits at 30, 60, and 90 days. The results obtained showed that the host tissue well accepted the new biphasic material;the presence of new bone formation was observed. A more complete resorption was observed for the new microcrystalline biphasic material compared to for a commercial m>βm>-TCP material.

关键词： microcrystalline Beta-Tricalcium Phosphate Ceramic Bone Graft Glycolic Acid

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Differential Growth of Genotypes of Physic Nut Conditioned by Nitrogen Fertilization

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American Journal of Plant Sciences 2014年第14期5卷 2154-2162页

作者： Tafarel Victor Colodetti Leonardo Fardim Christo Lima deleon martins Wagner Nunes Rodrigues José Francisco Teixeira do Amaral Bruno galvêas Laviola marcelo Antonio Tomaz Centro de Ciências Agrárias Universidade Federal do Espírito Santo (CCA/UFES) Alegre Brazil Empresa Brasileira de Pesquisa Agropecuária Embrapa Agroenergia Brasília Brazil

The adequate supply of nitrogen is essential for the plant metabolism. This nutrient has an irreplaceable role on the vegetative and reproductive growth of physic nut;therefore the correct management of the fertilization is very important, particularly in tropical regions, which present considerable losses of nitrogen by leaching and volatilization processes. This study was made with the objective of evaluating the growth of genotypes of physic nut conditioned by nitrogen fertilization. The experiment was conducted in controlled environment, following a factorial scheme 12 × 4, with 12 Brazilian genotypes of Jatropha curcas L. and 4 levels of nitrogen fertilization (0%, 50%, 100% and 150% of the recommendation), in completely randomized design, with four replications. The growth of the genotypes was evaluated at 100 days of cultivation. Positive response to the increase in the nitrogen supply was observed in most genotypes, with gain in plant height, stem diameter, number of leaves, leaf area and root volume. The levels of nitrogen fertilization promoted differential growth between genotypes, being possible to identify genotypes with superior growth for each level.

关键词： Jatropha curcas L. mineral Nutrition Vegetative Growth

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Prevalence, Risk Factors and Intra-Hospital outcomes Relating to Peri-Intraventricular Hemorrhage in Premature Newborns of Gestational Age Less than 34 Weeks

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open Journal of obstetrics and Gynecology（妇产科期刊） 2021年第7期

作者： Ana Frante de Holanda Pinto Vasconcelos Kaliny da Silva galvão Rodrigo Daudt Tenório Ana Clara monteiro Laranjeira Délia maria de m.L.Herrmann Diêgo Lucas Ramos e Silva Juliana Barbosa Nunes Cavalcante Jamille Campos sousa Euclides maurício Trindade Filho

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Evaluation of the Quality of Life in Pre- and Post-operatory in Patients Submitted to Surgical Treatment of Reflux Disease and Hiato Hernia

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Surgical Science（外科学） 2023年第6期

作者： Fernando Athayde Veloso madureira Roosevelt Filho Priscila Panisset Figueiredo galvão

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Terahertz modulation of Hexagonal-Shaped metamaterials Employing Zno Quantum Dots

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open Journal of Inorganic Non 2019年第1期9卷 1-13页

作者： Clarissa D. Vázquez-Colón Alvaro Flores-Pacheco Janeth Alexandra García-monge Juan Adrián Zepeda-galvéz Daniel Shreiber Arturo Ayón The University of Texas at San Antonio San Antonio Texas USA departamento de Física Universidad de Sonora Hermosillo Sonora México US Army Research Laboratory Aberdeen Proving Ground MD USA

The utilization of UV excitation to verify the terahertz (THz) wave modulation of hexagonal-shaped metamaterial (mm) arrays coated with synthesized photoluminescent, down-shifting Zno quantum dots (QDs) of two different radius sizes, namely, 3.00 nm (pH 10) and 2.12 nm (pH 12), respectively is reported. In order to characterize the behavior of the mm before and after deployment of the Zno QDs, THz time domain spectroscopy in transmission mode was employed. Upon exposure to UV excitation, the collected amplitude modulation values were 9.21% for the pH 12 and 4.55% for the pH 10 Zno QDs, respectively. It is anticipated that the ability to actively tune the performance of otherwise passive structures will promote the proliferation of THz signal modulation devices in the near future.

关键词： Terahertz metamaterials Quantum Dots Terahertz Spectroscopy modulation

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Genetic Variability among Genotypes of Physic Nut Regarding Seed Biometry

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American Journal of Plant Sciences 2014年第10期5卷 1416-1422页

作者： Leonardo Fardim Christo Tafarel Victor Colodetti Wagner Nunes Rodrigues Lima deleon martins Sebastiao Batista Brinate JoséFrancisco Teixeira do Amaral Bruno galvêas Laviola marcelo Antonio Tomaz Centro de Ciências Agrárias Universidade Federal do Espírito Santo(CCA/UFES)AlegreBrazil Empresa Brasileira de Pesquisa Agropecuária Embrapa AgroenergiaBrasíliaBrazil

With probable center of origin in Brazil, the species Jatropha curcas L., known as physic nut, is a tropical oilseed with potential for cultivation aiming at the production of biodiesel. This study was conducted with the objective of investigating the genetic variability regarding the morphology of seeds of physic nut, using biometric analyses to identify variables that have potential for the study of the diversity of the species and the classification of genotypes. Seeds of 22 genotypes of physic nut, from the germplasm bank of Embrapa Agroenergia (Brazil) were evaluated regarding characteristics of size and mass. The genotypes of Jatropha curcas L. selected by the Brazilian breeding program presented high diversity for characteristics of the seeds, allowing the exploration of this genetic variability to classify genotypes in different groups. In addition, variables related to the biomass of the seeds present high relative contributions to the diversity observed in the genotypes.

关键词： Jatropha curcas Diversity Size Shape Biomass

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