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Physical and chemical characterization of sediments from an Andean river exposed to mining and agricultural activities: The Moquegua River, Peru

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International Journal of Sediment Research 2022年第6期37卷 780-793页

作者： luis de los santos valladares Juan luis Ccamapaza Renato Arturo Valencia-Bedregal luis Enrique Borja-Castro Jose Velazquez-Garcia dehiwalage Harshani Nimalika Perera Adrian Ionescu David Arvidsson Eustace Peregrine Barnes Peter Newton Hugo Lepage Patrick Byrne Angel Guillermo Bustamante Dominguez Crispin H.W.Barnes Cavendish Laboratory Department of Physics University of Cambridge Escuela Acad emico Profesional de Ingeniería Ambiental Universidad Nacional de Moquegua Provincia de Mariscal Nieto Laboratorio de Cer amicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos School of Biological and Environmental Science Liverpool John Moores University

This study presents an analysis of sediments in an Andean river impacted by both natural conditions and anthropogenic activities. Fifty samples were collected from selected sites throughout the Moquegua River drainage basin, and Tambo River headwaters at Pasto Grande, in Peru, and analysed with X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Si, Ca, Al, Fe, and O, common constituents of soils, were dominant, along with K, N, and P. The latter originating as primary macronutrients or chemical residuals from fertilizers used in agriculture. Higher concentrations of macronutrients and organic components were found in agricultural and urban areas, respectively. Arsenic minerals were also detected, which occur naturally, but possibly at levels augmented by anthropogenic activity. The application of cluster analysis revealed clustering between arsenic, arsenolite, and potassium but no significant geospatial correlation between sample sites in the drainage basin.

关键词： Andean river Moquegua river Sediments Fourier-transform infrared spectroscopy TG-DTG/DTA Clustering analysis

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Structural and Magnetic Properties of Monophasic Maghemite (γ-Fe2O3) Nanocrystalline Powder

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Advances in Nanoparticles 2014年第3期3卷 114-121页

作者： Juan Adrián Ramos Guivar Arturo Isaías Martínez Ana Osorio Anaya luis de los santos valladares Lizbet León Félix Angel Bustamante Dominguez Cavendish Laboratory Department of Physics University of Cambridge Cambridge UK Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional Cinvestav Unidad Saltillo Ciudad de México México Ciudad de México México Laboratorio de Cerámicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos Lima Perú Laboratorio de Nanotecnología e Innovación Tecnológica Departamento de Química e Ingeniería Química Universidad Nacional Mayor de San Marcos Lima Perú Núcleo de Física Aplicada Instituto de Física Universidade de Brasília Brasília Brasil

Structural and magnetic studies of monophasic maghemite (γ-Fe2O3) magnetic nanocrystallites (MNCs) synthesized by the co-precipitation chemical route are reported in this paper. For the synthesis, a starting precursor of magnetite (Fe3O4) in basic medium was oxidized at room temperature by adjusting the pH = 3.5 at 80°C in an acidic medium without surfactants. X-ray diffraction (XRD) pattern shows widened peaks indicating nanometric size and Rietveld Refinement confirms only one single-phase assigned to γ-Fe2O3 MNCs. High Resolution Transmission Electron Microscopy (HR-TEM) demonstrates the formation of nanoparticles with diameter around D ≈ 6.8 ± 0.1 nm which is in good agreement with Rietveld Refinement (6.4 ± 1 nm). A selected area electron diffraction pattern was carried out to complement the study of the crystalline structure of the γ-Fe2O3 MNCs. M(H) measurements taken at different temperatures show almost zero coercivity and remanence indicating superparamagnetic domain and high magnetic saturation.

关键词： Monophasic Nanomaghemite Rietveld Refinement TEM SAED M-H Loops ZFC

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Chemical Solution deposition of YBa2Cu3O7 Films on YSZ （100） Substrates

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Journal of Chemistry and Chemical Engineering 2014年第6期8卷 547-551页

作者： Henry Elías Sanchez Comejo Angel Bustamante Dominguez1 Ana María Osorio luis de los santos valladares José Albino Aguiar Crispin H. W. Barnes Ceramics and Nanomaterials Laboratory Department of Physics Major National University of San Marcos Lima 14-0149 Peru department of Chemistry and Chemical Engineering Major National University of San Marcos Lima 14-0149 Peru Superconductivity and Advanced Materials Laboratory Department of Physics Federal University of Pernambuco Recife50670-901 Brazil Cavendish Laboratory Department of Physics University of Cambridge Cambridge CB3 0HE United Kingdom

We report the epitaxial growth of YBCO (YBa 2 Cu 3 O 7 ) films on YSZ (Yttria-stabilized Zirconia) (100) substrates by chemical solution deposition. The precursor solution was prepared by dissolving stoichiometric amounts of acetates of Y(OOCCH 3 ) 3 ·4H 2 O, Ba(OOCCH 3 ) 2 and Cu(OOCCH 3 )·2H 2 O in an aqueous solution of oxalic acid (H 2 C 2 O 4 ) and following the sol-gel route. This solution was directly dripped onto YSZ (100) substrates with the help of a Fisher pipette. To form the YBCO film, the sample was crystallized by annealing at 860 °C for 12 h in an oxidizing atmosphere. The characterization was performed by XRD (X-ray diffraction) analysis which revealed high intensity (001) reflections and denoted that most of the grains were c-axis oriented. Randomly oriented grains and other phases such as Y 2 BaCuO 5 and CuO were also detected. The superconducting YBCO phase is demonstrated from the susceptibility versus temperature measurements which indicate a superconducting critical temperature ≈ 90 K. In addition, a surface morphology analysis was performed by optical microscopy and atomic force microscopy which revealed an average roughness of 0.2197 μm.

关键词： YBa2Cu3O7 化学溶液沉积 YBCO薄膜 YSZ 氧化钇稳定的氧化锆超导临界温度原子力显微镜 X射线衍射

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Crystallization and Morphology of Gold Thin Films on Unpolished Si（100） Substrates after Furnace and Flame Annealing

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材料科学与工程（中英文版） 2010年第1期4卷 1-10页

作者： luis de los santos V Angel Bustamante D. Lizbet Leon F. Thanos Mitrelias Adrian Ionescu JustinianoQuispe M. Crispin H. W. Barnes Cavendish Laboratory University of Cambridge J. J Thomson .Av. Cambridge CB3 0HE United Kingdom Facultad de Ciencias Fisicas Universidad Nacional Mayor de San Marcos Ap. Postal 14-0149 Peru

A crystallization and surface evolution study of Au thin film on unpolished Si(100) substrates after annealing at different temperatures above the eutectic point of the Au/Si system are reported. Samples were prepared by conventional evaporation of gold in high vacuum (10-7mbar) environment on substrates at room temperature. Thermal treatments were performed by both furnace and flame annealing techniques. After evaporation, some Au crystallizes were textured in the (111) direction. However, most of the thin film was amorphous and gold silicides such as Au7Si and Au3Si were also found. This crystallization can be achieved by furnace annealing or flame annealing in spite of the differences between their cell parameters. Annealing overcomes the mismatch between the cell parameters arranging the Au layers in the (111) direction and forming gold islands on the surface. Crystallization of gold strongly depends on both, the temperature and time of annealing. Epitaxial formation of Au can be easily reached after some minutes in the case of flame annealing. The epitaxial temperature for Au/Si(100) should be around the eutectic (363 oC). Above the eutectic point, the Au layer melt, the melting starts most likely from grain boundaries and from the interface allowing the islands separate even further and change shapes until hexagonal geometries. The mean crystallite diameters grow up to a maximum mean size of around 90 nm. The free activation energy for grain boundary migration above the eutectic temperature is 0.09 eV. Therefore the type of the silicon substrate changes the mechanism of diffusion and growth of crystallites during annealing of the Au/Si system.

关键词：退火工艺薄膜形貌热处理炉硅衬底黄金火焰结晶糙米

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Evaluation of Native Strains of Isaria fumosorosea （Wize） Against Anastrepha ludens （Loew）（Diptera： Tephritidae）

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Journal of Life Sciences 2012年第8期6卷 957-960页

作者： Fatima Lizeth Gandarilla-Pacheco Hector Daniel Nava-Gonzalez Katiushka Arevalo-Nifio luis JesusGalan-Wong Myriam Elias-santos Isela Quintero-Zapata Instituto de Biotecnologla Facultad de Ciencias Biol6gicas Universidad Aut6noma de Nuevo Le6n San Nicolas de los GarzaN.L. 66450 Mdxico

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Turbo-taxonomy to assemble a megadiverse lichen genus:seventy new species of Cora(Basidiomycota:Agaricales:Hygrophoraceae),honouring David Leslie Hawksworth’s seventieth birthday

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Fungal Diversity 2017年第3期84卷 139-207页

作者： Robert Lücking Manuela Dal Forno Bibiana Moncada luis Fernando Coca Leidy Yasmín Vargas-Mendoza André Aptroot Laura Juliana Arias Betty Besal Frank Bungartz Diego Mauricio Cabrera-Amaya Marcela E.S.Cáceres José luis Chaves Sionara Eliasaro Martha Cecilia Gutiérrez Jesús E.Hernández Marin María de los Ángeles Herrera-Campos María E.Holgado-Rojas Harald Jonitz Martin Kukwa Fabiane Lucheta Santiago Madriñán Marcelo Pinto Marcelli Suzana Maria de Azevedo Martins Joel A.Mercado-Díaz Jorge Alberto Molina Eduardo A.Morales Peter R.Nelson Freddy Nugra Francisco Ortega Telma Paredes Ayda Lucía Patiño Rouchi Nadine Peláez-Pulido Rosa Emilia Pérez Pérez Gary B.Perlmutter Eimy Rivas-Plata Javier Robayo Camilo Rodríguez Diego Fernando Simijaca Edier Soto-Medina Adriano Afonso Spielmann Alejandra Suárez-Corredor Jean-Marc Torres Carlos Alberto Vargas Alba Yánez-Ayabaca Gothamie Weerakoon Karina Wilk Marcela Celis Pacheco Mauricio Diazgranados Grischa Brokamp Thomas Borsch Patrick M.Gillevet Masoumeh Sikaroodi James D.Lawrey Botanical Garden and Botanical Museum Berlin KöniginLuise-Straße 6-814195 BerlinGermany Science Education The Field Museum1400 South Lake ShoreChicagoIL 60605USA department of Botany Smithsonian InstitutionNational Museum of Natural History10th St Constitution Ave NWWashingtonDC 20560USA department of Environmental Science and Policy George Mason UniversityFairfaxVA 22030-4444USA Licenciatura en Biologı´a Universidad Distrital Francisco Jose´de CaldasCra.4 No.26D-54Torre de LaboratoriosHerbarioBogota´D.C.Colombia Herbario Universidad de Caldas(FAUC) Edificio BicentenarioCalle 65No.26-10ManizalesA.A.275CaldasColombia ABL Herbarium G.v.d.Veenstraat 1073762 XK SoestThe Netherlands Biologı´a Universidad del Quindı´oCarrera 15 Calle 12 NorteArmeniaQuindı´oColombia 120 Chavis Avenue LexingtonVA 24450USA Charles Darwin Foundation Puerto AyoraSanta Cruz IslandGala´pagosEcuador Schedestraße 8 53113 BonnGermany Jardı´n Bota´nico de Bogota´Jose´Celestino Mutis Avenida Calle 63 No.68-95Bogota´D.C.Colombia departamento de Biocieˆncias Universidade Federal de SergipeAvenida Vereador Olı´mpio Grandes/n.ItabaianaCEP:49.500-000 SergipeBrazil Laboratorio de Hongos Instituto Nacional de Biodiversidad(INBio)Apdo.22-3100Santo Domingo de HerediaCosta Rica departamento de Botaˆnica Universidade Federal do Parana´Campus Polite´cnicoSetor de Cieˆncias Biolo´gicasAv.Cel.Francisco H.dos Santoss/nJardim das Ame´ricas81531-980 CuritibaPRBrazil Ingenierı´a Ambiental Universidad Distrital Francisco Jose´de CaldasCarrera 5 Este No.15-82Av.CircumvalarBogota´D.C.Colombia Instituto Experimental Jardı´n Bota´nico Dr.Tobı´as Lasser Centro de Investigacio´n y DesarrolloUniversidad Central de VenezuelaAve.Salvador AllendeJardı´n Bota´nico de CaracasApartado#2156Caracas 1010-AVenezuela departamento de Bota´nica Instituto de Biologı´aUniversidad Nacional Auto´noma de Me´xicoApartado Postal 70-36704510 Ciudad De Me´xicoMexico Facultad de Ciencias Escuela Profesional de Biologı´aUniv

Following a large-scale phylogenetic study of the lichenized genus Cora(Basidiomycota:Agaricales:Hygrophoraceae),we formally describe 70 new species,honouring the seventieth birthday of David Leslie Hawksworth,one of the preeminent figures in mycology and lichenology in the past 50 years.Based on an updated phylogeny using the ITS fungal barcoding locus,we now recognize 189 taxa in a genus that until recently was considered to represent a single species;including this contribution,92 of these are formally recognized,including five taxa based on historical names or collections that have not been sequenced.Species of Cora can be recognized by a combination of morphological(size,colour,lobe configuration,surface hairs,hymenophore size and shape),anatomical(thallus thickness,cortex structure,photobiont type,hyphal papillae),and ecogeographical features(substrate,habitat,distribution),and a keytable allowing the identification of all accepted taxa is provided.The new species are:Cora accipiter Moncada,Madrin˜a´n&Lücking spec.nov.,C.applanata Moncada,Soto-Medina&Lücking spec.nov.,C.arachnodavidea Moncada,Dal Forno&Lücking spec.nov.,C.arborescens Dal Forno,Chaves&Lücking spec.nov.,C.arcabucana Moncada,C.Rodrı´guez&Lücking spec.nov.,C.aturucoa Lücking,Moncada&C.Vargas spec.nov.,C.auriculeslia Moncada,Ya´nez-Ayabaca&Lücking spec.nov.,C.barbifera Moncada,Patin˜o&Lücking spec.nov.,C.boleslia Lücking,E.Morales&Dal Forno spec.nov.,C.caliginosa Holgado,Rivas Plata&Perlmutter spec.nov.,C.campestris Dal Forno,Eliasaro&Spielmann spec.nov.,C.canari Nugra,Dal Forno&Lücking spec.nov.,C.caraana Lücking,Martins&Lucheta spec.nov.,C.casasolana Moncada,R.-E.Pe´rez&Lücking spec.nov.,C.caucensis Moncada,M.Gut.&Lücking spec.nov.,C.celestinoa Moncada,CabreraAmaya&Lücking spec.nov.,C.comaltepeca Moncada,R.-E.Pe´rez&Herrera-Camp.***.nov.,C.corani Lücking,E.Morales&Dal Forno spec.nov.,C.corelleslia Moncada,A.Sua´rez-Corredor&Lücking spec.nov.,C.crispoleslia Moncada,J.Molina&Lücking spec.nov.,C.cuzcoensis Holgado,Rivas Plata&Perlmutter spec.nov

关键词： Bolivia Citizen science Chile Mexico Puerto Rico Sri Lanka

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