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Synthesis of Hydrothermally Grown Zinc Oxide Nanowires

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Journal of Chemistry and Chemical Engineering 2012年第1期6卷 61-64页

作者： Concepcioen Mejia-Garcia Elvia Diaz-valdes Gerardo ortega-Cervantes Esteban Basurto-Cazares Departamento de Fisica Escuela Superior de Fisica y Matematicas de Instituto Politecnico Nacional Unidad Adolfo Lopez MateosMexico D. F. 07738 Mexico

We report the synthesis ofZnO nanowires grown on glass by spin coating and using a commercial microwave oven. 10 mM solutions of zinc acetate dehydrate and 12propanol were spin coated on glass at 2000 rpm for 60 s. A seed layer was obtained after three layers of spin coating. Vertical ZnO nanowires were then grown by dipping the substrate in an equimolar solution of zinc nitrate hexahydrate and hexamethylenetetramine subsequently, films were heated with a commercially microwave oven at different power settings （140, 350 and 700 W）. The ZnO nanowires were characterized optically and morphologically. Scanning electron microscopy analysis showed that the size of ZnO nanowires was 50 nm in diameter and 500 nm in length. XRD patterns and IR spectra revealed the presence of Zn（OH）2 on the films, when low power in the microwave oven was utilized. The ZnO nanowires bandgap energy was obtained from optical transmission spectra.

关键词： ZnO nanowires Scanning Electron Microscopy X-Ray Diffraction IR optical transmission.

Synthesis of Multi-component Mass-exchange Networks

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Chinese Journal of Chemical Engineering 2013年第4期21卷 376-381页

作者：刘琳琳都健 Mahmoud M. EI-Halwagi Jose Maria Ponce-ortega 姚平经 Chemical Engineering Department Dalian University of Technology Dalian 116024 China Chemical Engineering Department Texas A&M University College Station TX 77843 USA Adjunct Faculty at the Chemical and Materials Engineering Department King Abdulaziz University Jeddah Saudi Arabia Chemical Engineering Department Universidad Michoacana de San Nicolas de Hidalgo Morelia Mich 58060 Mexico

This paper presents a superstructure-based formulation for the synthesis of mass-exchange networks (MENs) considering multiple components. The superstructure is simplified by directly using the mass separation agents (MSA) from their sources, and therefore the automatic synthesis of the multi-component system involved in the MENs can be achieved without choosing a 'key-component' either for the whole process or the mass exchangers. A mathematical model is proposed to carry out the optimization process. The concentrations, flow rates, matches and unit operation displayed in the obtained network constitute the exact representation of the mass exchange process in terms of all species in the system. An example is used to illustrate and demonstrate the application of the proposed method.

关键词： multiple components mass exchange network superstructure optimization

Species richness and community structure of class Polyplacophora at the intertidal rocky shore on the marine priority region no.33,Mexico

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Open Journal of Ecology 2014年第2期4卷 43-52页

作者： Lizeth Galeana-Rebolledo Rafael Flores-Garza Adriana Reyes-Gomez Sergio Garcia-Ibanez Pedro Flores-Rodriguez Carmina Torreblanca-Ramirez Arcadio valdes-Gonzalez Unidad Academica de Ecologia Marina Universidad Autonoma de GuerreroAcapulcoMexico Universidad Autonoma de Nuevo Leon Laboratorio de AcuaculturaFacultad de Ciencias BiologicasCiudad UniversitariaSan Nicolas de los GarzaMexico

Marine Priority Region No. 33 (MPR 33) lies in the State of Guerrero, where the National Commission for Knowledge and Use of Biodiversity has declared a lack of information on marine species, Class POLYPLACOPHORA among others. This program was carried out on the rocky intertidal zone of MPR 33 with the objectives to: 1) determine species richness, 2) community composition based on families represented, 3) estimate the density, 4) index of diversity, 5) analyze body proportions and 6) geographic distribution of species. Three surveys on five sites were conducted during 2009 and 2012, using one mt2 quadrant for systematic sampling procedure;collecting all POLYPLACOPHORA specimens found within the quadrants, then proceeding with their preservation. 441 organisms were analyzed where 17 species were identified, on nine genera within six families. Fifteen new species were recorded for the MPR 33. Family ISCHNOCHITONIDAE Dall, 1889 was the best represented in species richness and CHITONIDAE Rafinesque, 1815 in abundance. Density of 8.82 organisms/m2, the H′ index was 2.38 bits/individuals and J′ = 0.57. The species Chiton (Chiton) articulatus Sowerby, 1832 showed the highest density, greater size and was found in all five collection sites. Three species, (Chiton (C.) articulatus, Ischnochiton (Ischnochiton) muscarius (Reeve, 1847) and Chiton (Chiton) alboli-neatus Broderip & Sowerby, 1829), were considered wide. Intertidal species richness was associated with habitat stability and wave intensity;the more unstable sites had greater richness while most stable sites lower. Species inventory and understanding the communities’ interactions of the marine fauna of the State of Guerrero are important;therefore these efforts must be continued.

关键词： Polyplacophora New Records Methodology RMP 33 Guerrero

Socioeconomic Aspects for Coastal Mollusk Commercial Fishing in Costa Chica,Guerrero,Mexico

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Natural Resources 2018年第6期9卷 229-241页

作者： Lizeth Galeana-Rebolledo Rafael Flores-Garza Juan Violante-Gonzalez Pedro Flores-Rodriguez Sergio Garcia-Ibanez Victor Landa-Jaime Arcadio valdes-Gonzalez Centro de Ciencias de Desarrollo Regional Pino s/n.Col.El RobleAcapulcoMéxico Facultad Ecologia Marina Gran Via TropicalN°20Fraccionamiento Las PlayasAcapulcoMexico Departamento de Estudios para el Desarrollo Sustentable de Zonas Costeras San Patricio-MelaqueMexico Facultad de Ciencias Biologicas Universidad Autonoma de Nuevo LeonCiudad UniversitariaSan Nicolas de los GarzaMexico

An important part of the fishing activity in Mexico is carried out in the coastal strip and has a strong social, economic and ecological importance. In the state of Guerrero, mollusks fishing is coastal and craftwork activity focused on a small number of species and without information on biology and reproductive or ecological aspects for most species caught. This research was carried out in the Costa Chica region, Guerrero, Mexico and the aims were: 1) To analyze the socioeconomic features of cooperative societies of fishing production;and 2) To know the diversity of mollusks caught by coastal fishing and the species that have the greatest importance in fishing. From February to April 2013-2015, seven fish coop units, four piers and places where seafood is sold were visited. For the socio-economic analysis and the determination of the species that have more importance in the coastal fishing, a total of 67 surveys were applied. In order to determine the cast of species, the specimens captured by the fishermen were used, which were identified and counted. A total of 67 interviews were analyzed and an average of $1806.00 was estimated as weekly economic income just as a product of fishing, it was also estimated that on average the fishermen work 4.3 days a week. Fisheries cooperatives market most of their produce directly to restaurateurs and locals on the piers. Replacement of older adults by young fishermen from the same region was observed, most are adults between 22 and 39 years old. 25 species of mollusks of economic importance were registered for the coastal fishermen of the Costa Chica. Six species were identified as the main target for catching fishermen. The fishing of mollusks in Costa Chica is not subject to any type of control, which has led to overfishing reflected in the decline sizes and banks in populations of commercial importance.

关键词： Molluscs Coastal Fishing Socioeconomic Fisherman

Commercially Important Marine Mollusks for Human Consumption in Acapulco,Mexico

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Natural Resources 2012年第1期3卷 11-17页

作者： Rafael Flores-Garza Sergio Garcia-Ibanez Pedro Flores-Rodriguez Carmina Torreblanca-Ramirez Lizeth Galeana-Rebolledo Arcadio valdes-Gonzalez Arquimedes Suastegui-Zarate Juan Violante-Gonzalez Unidad Academica de Ecologia Marina Universidad Autonoma de GuerreroAcapulcoMexico Facultad de Ciencias Biologicas Universidad Autonoma de Nuevo LeonCiudad UniversitariaSan Nicolas de los GarzaMexico

Acapulco, offers for international tourism a variety of mollusks that are delightful to the palate and a source of economic revenue for its residents;however there are no studies on the species consumed. Furthermore, data from the State agencies responsible for registration of these products are unclear. This work is aimed to develop an inventory of Gastropoda, Bivalvia and Polyplacophora marketed as food, to gain knowledge on the species native to Acapulco and the introduced ones. The places that sell shellfish were interviewed from 2008 to 2011 in order to determine the geographical origin of their products being offered. We identified 42 species: 15 species of gastropods are captured locally and three are introduced. On Bivalvia, seven species are caught locally and 16 are introduced. There are Bivalvia species caught locally;however, their capture is now unaffordable. It is likely that this situation is due to overfishing and/or the transmission of diseases or parasites caused by the introduction of foreign living organisms to Acapulco. Within the list of species caught locally, there are some listed as of subject protection;all of these organisms are exploited in Acapulco without control. The wealth of marine mollusks for human consumption in Acapulco is very high. The capture does not satisfy local market demand and the amount of introduced species is very high. It is necessary to make a diagnostic analysis of mollusk fishing industry in the state of Guerrero, also implement a management program, including the sanitary measures and control of introduced species, as they arrive alive and stay alive in the waters of Acapulco. A significant number of native species that have aquaculture potential should be studied for commercial culture practice as well as to conduct studies on their biology on those species that are considered over-exploited and allow recovery of the species in its habitat.

关键词： Mollusks Commercial Consumption Human Acapulco México

Land use impacts on parasitic infection: a cross-sectional epidemiological study on the role of irrigated agriculture in schistosome infection in a dammed landscape

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Infectious Diseases of Poverty 2021年第2期10卷 78-78页

作者： Andrea J.Lund David HRehkopf Susanne HSokolow MMoustapha Sam nicolas Jouanard Anne-Marie Schacht Simon Senghor Assane Fall Gilles Riveau Giulio ADe Leo David Lopez-Carr Emmett Interdisciplinary Program in Environment and Resources Stanford University473 Via Ortega Suite 226StanfordCAUSA 不详

Background:Water resources development promotes agricultural expansion and food *** are these benefits offset by increased infectious disease risk?Dam construction on the Senegal River in 1986 was followed by agricultural expansion and increased transmission of human *** the mechanisms linking these two processes at the individual and household levels remain *** investigated the association between household land use and schistosome infection in children.

关键词： Agriculture Exposure Livelihoods Planetary health Senegal Schistosomiasis Water contact