Nexo Revista Cientifica最新文献_第8页

Diseño y montaje de una planta piloto para la extracción de quitina y proteínas 几丁质和蛋白质提取中试装置的设计和装配

IF 0.3

Nexo Revista Cientifica Pub Date : 2010-09-03 DOI: 10.5377/NEXO.V22I2.42

D. Escorcia, D. Hernandez, Mario Sanchez, M. Benevente

{"title":"Diseño y montaje de una planta piloto para la extracción de quitina y proteínas","authors":"D. Escorcia, D. Hernandez, Mario Sanchez, M. Benevente","doi":"10.5377/NEXO.V22I2.42","DOIUrl":"https://doi.org/10.5377/NEXO.V22I2.42","url":null,"abstract":"The aim of this project was the design and set up of a pilot plant for chitin and proteins chemical recovery from shrimp shells and squat lobsters. The moisture content of the material and optimal experimental conditions of volume and concentration of the process reagents were determined. Additionally, a technical and economical analysis of production process was performed. The results showed that the raw material has high moisture content, between 68-80% wet basis, and the experimental conditions for chitin extraction depend strongly on the material characteristics. Under these conditions, recuperation of 98% for shrimp shells and approximately of 58% for squad lobster was obtained. On the other hand, the proteins recovery showed that the largest production occurs at pH 4.0 and using solutions from deproteination step without grinding of raw material. The technical study provided basic information about set up costs and operating process investment, and data about facilities and equipments related to productive process. The assessment revealed that an initial investment of US $ 10,520.94 for pilot plant set up and US $ 4,852.58 for transport and operating costs for six months must be done. Keywords: chemical method; chitin; pilot plant; proteins; shrimp shell; squat lobster.DOI: 10.5377/nexo.v22i2.42Nexo: Revista Cientifica Vol. 22, No. 02, pp.45-55/Diciembre 2009","PeriodicalId":40344,"journal":{"name":"Nexo Revista Cientifica","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2010-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70883891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Indicadores para la evaluación de la calidad ambiental del hábitat urbano 城市生境环境质量评价指标

IF 0.3

Nexo Revista Cientifica Pub Date : 2010-09-03 DOI: 10.5377/NEXO.V22I1.41

Á. Zúñiga

{"title":"Indicadores para la evaluación de la calidad ambiental del hábitat urbano","authors":"Á. Zúñiga","doi":"10.5377/NEXO.V22I1.41","DOIUrl":"https://doi.org/10.5377/NEXO.V22I1.41","url":null,"abstract":"This research involved the design and implementation of a methodology for assessing the quality of the built environment in urban settlements. The methodology began with the establishment of the state of the art on the subject, emphasizing the conceptual aspects of sustainability as the highest aspiration to achieve in the evaluation of a settlement and determining the significant components of the problem to work. Subsequently characterized the existing system of urban settlements in Nicaragua and identified settlements under study. Typological classifications were identified existing urban human settlements in Nicaragua, which was completed by proposing a new way of grouping according to the structuring of components, allowing the selection of settlements where you applied the instrumental. The following evaluation methodology developed consists of the theoretical tools, the histograms of environmental assessment and parent assessment of quality. It ended the instrumental validation process designed to apply to four selected settlements, based on a sample of 5% of all settlements in the area of study selected. We evaluated the results, relating them to other area analysis, which enabled to demonstrate their effectiveness and efficiency. Keywords: urban human settlements, habitat urban built environment, environmental quality. DOI: 10.5377/nexo.v22i1.41 Nexo: Revista Cientifica Vol.22, No.01, pp.23-31/Agosto 2009","PeriodicalId":40344,"journal":{"name":"Nexo Revista Cientifica","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2010-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70884006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Estimación de la carga de nutrientes procedentes de la cuenca de drenaje superficial del rio Tepenaguasapa 对Tepenaguasapa河流域地表排水的养分负荷的估计

IF 0.3

Nexo Revista Cientifica Pub Date : 2010-05-30 DOI: 10.5377/NEXO.V23I1.35

B. Morales, G. Chávez

{"title":"Estimación de la carga de nutrientes procedentes de la cuenca de drenaje superficial del rio Tepenaguasapa","authors":"B. Morales, G. Chávez","doi":"10.5377/NEXO.V23I1.35","DOIUrl":"https://doi.org/10.5377/NEXO.V23I1.35","url":null,"abstract":"El Lago Cocibolca merece atencion especial por ser una fuente importante de agua para el consumo humano. El rio Tepenaguasapa es una de sus subcuencas, que tiene entre otros problemas, la contaminacion con nutrientes. Para el estudio de este problema, fue necesario determinar la carga de nutrientes (Fosforo y Nitrogeno) procedentes de las subcuencas. La carga de Fosforo estimada fue de 24.33 t/ano y de Nitrogeno de 632.57 t/ano, para totalizar 656.89 t/ano, con un orden de importancia por su origen de: uso de suelo, precipitacion y escurrimiento artificial. El rio varia en su estado trofico con un gradiente de concentracion de nutrientes aguas arriba hacia aguas abajo. La carga de nutrientes es originada por la gran cantidad de area empleada para pasto y actividad ganadera extensiva, tierras de labranza, monocultivo, manejo de las aguas residuales, tala de arboles, ademas de ser una cuenca con abundante precipitacion y de gran tamano en comparacion con el espejo de agua. \u0000Palabras clave: fosforo; nitrogeno; actividad ganadera extensiva; carga de nutrientes; estado trofico. \u0000 \u0000DOI: http://dx.doi.org/10.5377/nexo.v23i1.35 \u0000 \u0000Nexo: Revista Cientifica Vol. 23, No. 01, pp.18-26/Mayo 2010","PeriodicalId":40344,"journal":{"name":"Nexo Revista Cientifica","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2010-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70883537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aplicación del concepto de participación ciudadana y su impacto en la gestión integral de los recursos hídricos. Caso cuenca del lago Cocibolca 公民参与概念的应用及其对水资源综合管理的影响。科奇博尔卡湖流域案例

IF 0.3

Nexo Revista Cientifica Pub Date : 2010-05-30 DOI: 10.5377/NEXO.V23I1.36

S. Espinal

引用次数: 0