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Solid-state synthesis of LnOCl/Ln_2O_3(Ln=Eu, Nd) by using chitosan and PS-co-P4VP as polymeric supports

Journal of Rare Earths 2018年第12期36卷 1326-1332页

作者： C.Diaz D.Carrillo R.de la Campa a.presa soto M.L.Valenzuela Departamento de Quimica Facultad de Quimica Universidad de Chile Departamento de Quimica Organica e Inorganica (IUQOEM) Facultad de Quimica Universidad de Oviedo Universidad Autonoma de Chile Facultad de Ingenieria Instituto de Ciendas Quimicas Aplicadas Inorganic Chemistry and Molecular Material Center

A series of lanthanide materials of type LnOCl or Ln2O3(Ln = Eu, Nd) were successfully prepared via a convenient and straightforward two-step procedure. Firstly, and by using chitosan and PS-co-P4 VP as polymeric supports, macromolecular complexes of type chitosan ·LnCl3and PS-co-P4 VP·LnCl3 were prepared. These macro molecular complexes were treated in solid state at 800 ℃ under air, leading to the corresponding LnOCl or Ln2O3materials(Ln = Eu, Nd) with moderate to good yields. The nature of the asprepared lanthanide materials(LnOCl and/or Ln2O3) is strongly influenced by the polymeric template(i.e.,chitosan or PS-co-P4 VP), the lanthanide salt precursor, and the polymer/lanthanide molar ratio. Thus, when chitosan · EuCl3and PS-co-P4 VP·EuCl3are used as macromolecular precursors, a mixture of crystalline phases of both EuOCl and Eu2O3are obtained. However, when chitosan· NdCl3and PS-co-P4 VP· NdCl3are used, a sole pure crystalline phase of NdOCl is obtained. The nano structured lanthanide materials were characterized by means of XRD(X-ray diffraction of powder), SEM, EDS, TEM, and HRTEM. The luminescent spectra of the asprepared EuOCI/Eu2O3mixture materials show an emission pattern whose intensity is strongly influenced by the nature of the polymeric precursor, as well as on the metal/polymer molar ratios.

关键词： EuOCl/Eu_2O_3 NdOCl Solventless method Luminescence Lanthanides Rare earths

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The importance of diet in osteoporosis

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Open Journal of Epidemiology 2013年第2期3卷 79-84页

作者： Nicolás Mendoza Jesús presa Antonio Martínez-Amat Fidel Hita Department of Health Sciences University of Jaen Jaen Spain Department of Obstetrics and Gynecology Hospital Princesa Sofia Jaen Spain Department of Obstetrics and Gynecology University of Granada Granada Spain

The knowledge of risk factors associated with the development of osteoporosis (OP) is vital in the prevention strategy of this disease and its physical and economic consequences. The epidemiological characteristics of our population of postmenopausal women exhibit a pattern similar to that described in other studies, showing a proportional relationship between the magnitude of the risk factor and the severity of osteopenia/osteoporosis. Moreover, we observed protective effects for several dietary factors, such as the consumption of fruits, vegetables, and cereals;the moderate consumption of fish, alcohol, and dairy products;and the low intake of red meat, on spinal bone mineral density (BMD). Only the intake of grains and vegetables exerted protective effects on hip BMD.

关键词： Osteoporosis Diet Risk Factors

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Chlorophyll Concentration and Morphological Diversity in Corn Lines at Different Vegetative Stages

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American Journal of Plant Sciences 2016年第7期7卷 1067-1076页

作者： Mariano Mendoza Elos Gilberto Rodríguez Pérez Francisco Cervantes Ortíz Luis Patricio Guevara Acevedo Enrique Andrio Enríquez Ma. Del Carmen Ojeda Zacarías Isabel presa Figuereo Sergio Alfredo Rodríguez Herrera José Antonio Rangel Lucio José Guadalupe Rivera Reyes Division of Graduate Studies and Research Institute Technologic of Roque Guanajuato Mexico University Autonomous Agrarian of Nuevo León Monterrey México University Autonomous Agrarian Antonio Narro Saltillo México

The objective of this study was to assess the chlorophyll content of corn lines at different vegetative stages and the diversity between them. The study was conducted in the experimental field of the Roque Institute of Technology (ITR) located in Roque, Celaya, Guanajuato, Mexico. We used 32 corn lines from CIMMYT and four lines from the breeding program of the ITR. The evaluation was conducted in the spring-summer cycle of 2014 at two planting dates. We used a completely randomized block design with three replications. The experimental unit consisted of two rows of five linear meters with a distance of 0.75 meters between rows. Chlorophyll was measured at six different stages: V6, VT, R3, R4, R5 and MF. The agronomic variables recorded were: PH, CH, LAC, LBC, FF, MF, PM, CC, CL, DC, RC, KR and GY. The results of the analysis of variance showed significant differences between lines, dates and their interaction. On average, 18 lines were found with chlorophyll concentrations above 51 SPAD units in the two environments. This indicated that these materials had a high potential for field performance. Using cluster analysis UPGMA method, we identified seven groups for chlorophyll and eight groups for agronomic characteristics for a breeding program. The groups were associated to the homogeneous characteristics of each variable.

关键词： Chlorophyll Content Phenological Stages Clusters and Corn Lines

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Isolation and Characterization of Mercury Resistant Trichoderma Strains from Soil with High Levels of Mercury and Its Effects on Arabidopsis thaliana Mercury Uptake

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Advances in Microbiology 2018年第7期8卷 600-613页

作者： JoséLuis Hernández-Flores JoséGerardo Bernal Melo Andrés Cruz Hernández Miguel A.Ramos López Carlos Saldana Gutiérrez Sergio Romero Gomez Victor Pérez Moreno Rosa P.Calvillo Medina JoséHumberto Valenzuela soto Sergio Pacheco Hernández George H.Jones Sergio Casas Flores Juan Campos-Guillen Laboratorio de Bioseguridad y Análisis de Riesgo Departamento de Ingeniería Genética de PlantasCentro de Investigación y de Estudios Avanzados del IPNIrapuatoGto.México Facultad de Química Universidad Autónoma de QuerétaroCerro de las Campanas s/nQuerétaroQro.México Escuela de Agronomía Universidad De La Salle Bajíocampus Campestre.LeónGto.México Facultad de Ciencias Naturales Universidad Autónoma de QuerétaroAv.De las Ciencias S/NQuerétaroQro.México Centro de Investigación en Química Aplicada Blvd.Enrique Reyna Hermosillo No.140SaltilloCoahuilaMéxico Department of Biology Emory UniversityAtlantaGeorgiaUSA IPICYT División de Biología Molecular.Camino a la presa San JoséNo.2055Colonia Lomas 4a sección.C.P.San Luis PotosíMexico

Traditional mining activities are usually correlated with high levels of soil pollution, which is a major environmental concern. Extensive mining activities have taken place in the San Joaquin region in the State of Querétaro, México resulting in high levels of mercury soil pollution (up to 1532 ± 300 mg/kg). We isolated mercury-resistant fungal strains from the San Joaquin region soils and identified them through morphologic characteristics and ITS rDNA region sequence analysis. We determined that fungi isolated belong to the genus Trichoderma. All the isolates selected showed the ability to catalyze the volatilization of Hg. For air sampling, an active sampling device was constructed and using acid KMnO4 as an absorbent, the concentration of mercury in solution was determined through the cold vapor atomic absorption method. The results show mercury volatilization from the fungal species assay, with a maximum of 213.04 ± 32.6 μg/m3 while mycelium accumulation ranged from less than 17.5 ± 2.9 to 20.0 ± 3.4 μg/g. The fungal isolates were also evaluated for their ability to reduce mercury uptake in Arabidopsis thaliana. These observations suggest the utility of Trichoderma for the mobilization of mercury in those contaminated soils.

关键词： Volatilization Mercury Trichoderma Soil Bioremediation

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