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Exploración metodológica del potencial de formación de geles marinos

Methodological exploration of the marine gels formation potential

PAOLA JACQUELINE VALDES VILLAVERDE (2019)

En el océano se pueden encontrar estructuras gelatinosas tridimensionales compuestas principalmente de moléculas orgánicas como polisacáridos y proteínas. Estas estructuras pueden agregarse/desagregarse de forma continua debido a sus características aglutinantes y a fuerzas electrostáticas. Los geles orgánicos se distribuyen a lo largo del continuo de tamaños y, por lo tanto, su categorización como materia orgánica particulada (MOP) o disuelta (MOD) es difícil. Además, la cuantificación de los geles es compleja ya que los métodos actuales sólo permiten detectar ciertas fracciones de geles. La manera en que los geles impactan los diferentes reservorios de carbono y a la ecología de los microbios marinos son aspectos pobremente estudiados. En este proyecto se hizo una investigación metodológica para evaluar y controlar la formación de geles en muestras de agua de mar con el fin de generar información que ayude en futuras investigaciones sobre el papel de los geles en la ecología microbiana. Se realizaron filtraciones secuenciales de muestras de agua de mar para colecta y mediciones de carbono orgánico particulado (COP) y nitrógeno orgánico particulado (NOP). Se cuantificaron partículas exopoliméricas transparentes (PET) como referencia. Así mismo, se realizaron conteos bacterianos y pruebas de viscosidad. Nuestros resultados sugieren la formación de partículas orgánicas a partir de MOD en muestras filtradas. El carácter dinámico del intercambio entre MOD y MOP complica el control de la concentración de geles para investigar experimentalmente su papel en la ecofisiología de los procariontes heterotróficos. Los resultados de PET (0.13 a 2.15 µg XG eq·mL-1) son congruentes con lo antes reportado para la misma región. Los resultados de las pruebas de viscosidad sugieren que la influencia de la materia orgánica sobre la viscosidad no es significativa. En esta investigación destacó el potencial de la MOD para formar relativamente altas concentraciones de MOP. Las implicaciones ecológicas de este potencial de formación todavía deben de ser investigadas.

In the ocean three-dimensional gelatinous structures composed mainly of organic molecules such as polysaccharides and proteins can be found. These structures can aggregate/disaggregate continuously due to their agglutinative characteristics and electrostatic forces. Organic gels are distributed along the size continuum and so their categorization as particulate organic matter (POM) or dissolved organic matter (DOM) is difficult. In addition, the quantification of gels is complex since the current methods only allow to detect certain fractions of gels. In addition, the ways in which gels impact the different carbon reservoirs and the ecology of marine microbes are poorly studied aspects. In this project, a methodological investigation was made how to evaluate and control gel formation in seawater in order to generate information that will help in future research on the role of gels in microbial ecology. Sequential filtrations of seawater samples were carried out for the collection and measurement of particulate organic carbon (POC) and particulate organic nitrogen (PON). Transparent exopolymeric particles (TEP) were quantified as a reference. Also, bacterial counts and viscosity tests were performed. Our results suggest the formation of organic particles from DOM in filtered samples. The dynamic nature of the exchange between DOM and POM complicates the control of gels concentration to experimentally investigate their role in the ecophysiology of heterotrophic prokaryotes. TEP results (0.13 to 2.15 µ g XG eq mL-1) are similar to those previously reported for the same region. Viscosity tests results suggest that the influence of organic matter on viscosity is not significant. The noteworthy result of this research is the potential of DOM to form relatively high concentrations of POM. The ecological consequences of this formation have yet to be investigated.

Master thesis

Geles orgánicos, MOD, MOP, COP, PET, partículas Organic gels, DOM, POM, POC, TEP, particles CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA BIOLÓGICA OCEANOGRAFÍA BIOLÓGICA

Stabilization of bed Inclination angle in rotary drums by using computer vision

CLAUDIA PATRICIA FLORES GUTIERREZ ANTONIO REYES OBANDO OCTAVIO ISRAEL RENTERIA VIDALES Alejandro Ricardo Femat Flores (2018)

"Computer vision systems have had great importance in research of different industrial processes. Videos and photographs have been used to characterize the bed behavior in a rotary drum; in this way, the bed motion, repose angles, trajectories, and particle velocity can be determined This work shows the development of a computer vision system that measures the bed inclination angle in industrial rotary drums. The purpose of the vision system is to capture the images when the angular velocity on the drum changes. Eventually, with the data measured during the two experiments in industrial rotary drums, we have identified two input-output models representing the slumping motion. Based on the control objective, we considered two approaches: regulation and tracking PI and PII2 controllers have been designed to show that a bed inclination angle can be stabilized for rolling motion considering plants that represent slumping motion and the inclination angle as the measured variable."

Article

Rotating drum Granular material Rolling bed Kilns Flow Motion Particles Behavior Solids Transition INGENIERÍA Y TECNOLOGÍA INGENIERÍA Y TECNOLOGÍA

Animal based organic nutrition can substitute inorganic fertigation in soillessgrown grape tomato

OSCAR GUAJARDO RIOS CARLOS JAVIER LOZANO CAVAZOS LUIS ALONSO VALDEZ AGUILAR ADALBERTO BENAVIDES MENDOZA LUIS IBARRA JIMÉNEZ JUAN ALBERTO ASCACIO VALDES CRISTÓBAL NOÉ AGUILAR GONZÁLEZ (2017)

"Purpose: In recent years, interest in plant nutrition research has arisen with a strong focus on organic forms The aim of this study was to determine the effect of diferent organic fertilizers on growth, yield, fruit quality and polyphenol content in soilless grown grape tomatoes under greenhouse conditions."

Article

Nitrogen Organic Omri Polyphenols Solanum - lycopersicum l CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Captura de micropartículas usando campo evanescente fotorrefractivo

SUSANA ALEJANDRA TORRES HURTADO (2012)

We captured silicon oxide microparticles immersed in water on the surface of a crystal of LiNbO3:Fe. The photorefractive crystal form space charge distribution and electric field constant space charge within the crystal and an evanescent field at the surface. We obtained values for the evanescent field and the dielectrophoresis force, and determine the position of the particles in relation to the incident beam position. We also a relationship between the potency reaching the glass surface with the time in which capture is achieved.

Se logró la captura de micropartículas de óxido de silicio inmersas en agua sobre la superficie de un cristal de LiNbO3:Fe. El cristal foto refractivo forma una distribución de carga espacial y a su vez, un campo eléctrico de carga espacial constante dentro del cristal y un campo evanescente en la superficie. Se obtuvieron los valores para el campo evanescente y la fuerza de dielectroforesis, y se determinó la posición de las partículas en relación a la posición del haz incidente. También se hizo una relación entre la potencia que llegó a la superficie del cristal con el tiempo en que se logró la captura.

Master thesis

Electrophoresis Photorefractive effect Radiation pressure Dielectric particles CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

HIGH-ACCURACY PARTICLE POSITIONING TOGETHER WITH OPTIMUM DATA DISPLAY FOR VELOCIMETRY APPLICATIONS

DAVID MORENO HERNANDEZ (2000)

"Three-dimensional position and velocity information can be extracted by directly analysing the diffraction patterns of seeding particles in imaging velocimetry using realtime CCD cameras. The Generalised Lorenz-Mie theory is shown to yield quantitative accurate models of particle position, such that it can be deduced from typical experimental particle images with an accuracy of the order of 20 µm and an error of 11 grey levels RMS, data obtained by comparing theoretical and experimental images. Both, the theory and experimental verification of the problem presented here are discussed. This thesis present also a method which determines the optimum grid size for interpolated velocimetry data, without making any priori assumptions about the velocity fields, the system used or analysis method. The method employs condition number as the main criterion for deciding the adequate grid size for a given data set. Data sets displayed accordingly are directly comparable, independently of differing experimental parameters or data processing methods. The discussion is based on Computational Fluid Dynamics (CFD) data of flow past the near wake of a cylinder from which simulated PIV images were generated. These images were analysed with the proposed method and the velocity estimates compared to the CFD data. The method was also applied to a sample PIV image of turbulent flow in a baffled tube."

Doctoral thesis

Particle image velocimetry 3D PIV Spherical particles CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Anthropogenic Particles Study of Chihuahua-Mexico, Morphology and Elemental Composition

BALTER TRUJILLO NAVARRETE FRANCISCO PARAGUAY DELGADO ALFREDO CAMPOS TRUJILLO (2010)

The urban aerosol has been studied in general and there are few detailed analyzes that determine

the specific contribution of anthropogenic sources, we study ten industrial production process

located in Chihuahua, City. According to the permanent report by Air-Quality-Monitoring-

System about the particulate matter level from the city, it is close to the regulatory limit level and

missing information concerning the type of morphology and elemental composition of particles

size minor to 1.0 μm. The main goal of this study was to characterize the individual morphology

and elemental composition of anthropogenic particulate matter generated in this city. The

particles samples were collected during 2009 between June and August, the monitoring time was

around 20 minutes. We used Eight-Stage-Non-Viable-cascade-Impactor-Mark-II and selected

aerodynamic diameter 1.1μm for study in detailed. TEM-grid was placed at this stage to

collected sample; they were studied by transmission electron microscope model CM-200-

Philips® with elemental analysis system. The NIH ImageJ software was used for treatment and

analyses the acquired images. From 358 particles analyzed we determined mean values for

diameter of Feret (DF), compactness ratio (C), lacunarity (Lm and Lp), perimeter and density

fractal dimension (Dm and Dp). From data analyzed we can classify into four morphology types,

and they are spherical for polymeric, irregular shape for ceramic, cubic for metallic and

aggregates for fuel oil handling. The elemental composition is related with morphologies, we

find clearly typical morphologies categorically distinguishable.

Conference proceedings

Anthropogenic particles BIOLOGÍA Y QUÍMICA QUÍMICA OTRAS ESPECIALIDADES QUÍMICAS OTRAS

Chemical stability of superhard rhenium diboride at oxygen and moisture ambient environmental conditions prepared by mechanical milling

MIZRAIM GUILLERMO GRANADOS FITCH JUAN MANUEL QUINTANA MELGOZA Erick Adrián Juárez Arellano MIGUEL AVALOS BORJA (2018)

"In this study, rhenium diboride (ReB2) was obtained by mechanosynthesis at 640 minutes of milling. The obtained ReB2 was stored at oxygen and moisture ambient environmental conditions to know the chemical stability. The results indicate that ReB2 is totally decomposed at oxygen and moisture ambient environmental conditions. Furthermore, the X-ray diffraction (XRD) analysis of ReB2 samples after 26 months of storage shows that the final products of degradation are HReO4 (liquid), H3BO3, HBO2, and ReO3. Finally, a schematic diagram of the degradation sequence of ReB2 at oxygen and moisture ambient environmental conditions is proposed and validated with a thermodynamic analysis."

Article

Degradation Mechanosynthesis Octahedral particles Rhenium diboride INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE MATERIALES TECNOLOGÍA DE MATERIALES

Fabricación y caracterización de películas delgadas orgánicas para su aplicación en dispositivos optoelectrónicos

ARAMIS AZURI SANCHEZ JUAREZ (2013)

The work presented in this thesis, is for technological development work to manufacture

samples based on organic semiconductors; regioregular poly (3-hexylthiophene-2,5-diyl)

[P3HT] and [6,6]-Phenyl-C61-butyric acid methyl ester [PCBM], in order to study the

properties and the influences of environmental factors, storage and temperature

controlled treatment and solvent. All this resulted in the development of manufacturing

programs for functional organic semiconductor films, stable, repeatable and controllable

thickness. The culmination of the work is given by the development of a manufacturing

program for a functional, stable and repeatable organic photovoltaic device. This work

puts INAOE (Mexico) as one of the pioneering research centers for research in organic

semiconductor materials such as the processes developed are applicable to other types of

organic semiconductors other than those used in this thesis.

El trabajo presentado en esta tesis corresponde a un trabajo de desarrollo tecnológico

para la fabricación de muestras a base de semiconductores orgánicos; Regioregular

poly(3-hexylthiophene-2,5-diyl) [P3HT] y [6,6]-Phenyl-C61-butyric acid methyl ester

[PCBM], con la finalidad de estudiar las propiedades y las influencias de factores

ambientales de almacenamiento, así como de tratamientos controlados de temperatura y

solvente. Todo esto dio como resultado el desarrollo de programas de fabricación de

películas de semiconductor orgánico funcionales, estables y repetibles con grosor

controlable. La culminación del trabajo se da con la elaboración de un programa de

fabricación, para un dispositivo fotovoltaico funcional, estable y repetible a base de

semiconductores orgánicos. Este trabajo coloca a INAOE como uno de los centros de

investigación pioneros en México para la investigación de dispositivos de este tipo de

materiales.

Doctoral thesis

Optoelectronic devices Thin films Thin film devices Organic semiconductors CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Vermicompost, bacterias promotoras de crecimiento y hongos endomicorrízicos en chile jalapeño (Capsicum annuum L).

SALVADOR RIOS PEREZ (2015)

Tesis (Maestría en Ciencias, especialista en Edafología).- Colegio de Postgraduados, 2015.

Los fertilizantes químicos presentan baja eficiencia (≤50%) de asimilación por los cultivos. El fertilizante no aprovechado por las plantas puede tener un impacto ambiental adverso, como contaminación de mantos acuíferos, eutrofización, lluvia ácida y calentamiento global. Una alternativa al uso de los fertilizantes químicos son los biofertilizantes y materiales orgánicos como el vermicompost; que pueden sustituir parcial o totalmente la fertilización química. Los abonos orgánicos favorecen la dinámica del suelo desde el punto de vista del desarrollo vegetal; la actividad macro y microbiana reducen los costos del uso de fertilizantes químicos. En este trabajo se evaluó el efecto de cinco dosis de vermicompost 0, 0.5, 1, 2 y 3 t ha-1 aportando (0, 6.85, 13.7, 27.4 y 41.1 kg de N ha-1) en comparación con dos dosis de fertilizantes químicos 30 y 60 kg de N ha-1, en el crecimiento de chile jalapeño. Los resultados indican que la utilización de vermicompost en el cultivo del chile jalapeño (Capsicum annuum L.) tiene efectos positivos en el desarrollo del cultivo con la dosis de 1 t ha-1 en comparación a los tratamientos con fertilización química. En el segundo experimento se observó que cuando las plantas son inoculadas con HMA, RPCV y HMA+RPCV fertilizadas con vermicompost a 1 t ha-1 + urea 240 kg ha-1 se obtienen los mejores resultados en las variables altura de planta con 41.2 cm en comparación al testigo 29,4, para número de hojas el HMA+RPCV fertilizado con urea y vermicompost 78.6 y el testigo 42.6, área foliar el tratamiento HMA+RPCV fertilizado obtuvo 1170.29 en comparación al testigo 355.35 cm2, para el número de frutos el tratamiento con HMA+RPCV fertilizado 16.2 y el testigo 7.6 chiles, peso fresco el tratamiento HMA+RPCV y fertilizado 161.46 en comparación al testigo con 113.42 g. por lo tanto se observó mejores resultados al convinar HMA+RPCV y fertilizado con urea a la dosis de 240 kg ha-1 y vermicompost a la dosis de 1 t ha-1 se obtienen los mejores resultados. _______________ VERMICOMPOST, PLANT GROWTH PROMOTING RHIZOBACTERIAS AND ARBUSCULAR ENDOMYCORRHIZAL FUNGI ON CHILI (Capsicum annuum L.). ABSTRACT: Chemical fertilizers are inefficient (≤50%) of assimilation by crops. The fertilizer not used by plants may have an adverse environmental impact, such as pollution of groundwater, eutrophication, acid rain and global warming. An alternative to using chemical fertilizers are bio-fertilizers and organic materials such as vermicompost; which can partially or completely replace chemical fertilizers., Organic fertilizers promote soil dynamics from the viewpoint of plant growth; the macro and microbial activity reduce the costs of using chemical fertilizers. This research evalued the effect of five doses of vermicompost: 0, 0.5, 1, 2 and 3 t ha-1 providing 0, 6.85, 13.7, 27.4 and 41.1 kg N ha 1 respectively, compared with two doses of chemical fertilizers 30 and 60 kg N ha -1 in chili jalapeño (Capsicum annuum L.) growth. The results indicate that the use of vermicompost in chili jalapeño crops has positive effects on growth crop at a dose of 1 t ha-1 compared to chemical fertilizer treatments. In the second experiment, we observed that when the plants are inoculated with HMA, RPCV and HMA + RPCV fertilized with vermicompost to 1 t ha-1 + urea 240 kg ha-1 the best results in plant height with 41.2 cm, compared with the control 29.4; for number of sheets for the HMA + RPCV fertilized with urea and vermicompost and control 78.6 42.6; leaf area RPCV the HMA + fertilized treatment compared with 1170.29 won control 355.35 cm2, the number of fruits for treatment HMA + RPCV fertilized and control 16.2 7.6 chiles, fresh weight RPCV the HMA + fertilized treatment and 161.46 compared with control 113.42 g. Therefore the best results were observed combining HMA + RPCV and fertilized with urea at a dose of 240 kg ha-1 and vermicompost dose of 1 t ha-1.

Master thesis

Fertilizantes orgánicos Chile jalapeño Hongos micorrízicos Rizobacterias Organic fertilizers Chili jalapeño Mycorrhizal fungi Rhizobacteria Edafología Maestría CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS AGROQUÍMICA UTILIZACIÓN DE ABONOS

Calidad e inocuidad de jitomate (Lycopersicum esculentum L) fresco almacenado a diferentes temperaturas: relación del contenido de azúcares y ácidos orgánicos con la adherencia de Escherichia coli (ECET)

DIEGO IBARRA CANTUN (2012)

Tesis (Maestría en Ciencias, especialista en Estrategias para el Desarrollo Agrícola Regional).- Colegio de Postgraduados, 2012.

La inocuidad es un requisito importante de aceptación en el jitomate (Lycopersicum esculentum L.), para permitirle abrir nuevos mercados. En los que además, el fruto debe cumplir con ciertos estándares de calidad relacionados con sus propiedades físicas y químicas. El presente trabajo tuvo como objetivo determinar las propiedades físicas y químicas del fruto de jitomate almacenado a diferentes temperaturas en presencia de Escherichia coli (ECET). Se utilizaron frutos de jitomate variedad Charleston, cultivados en invernadero de hidroponía en el Municipio de Aquixtla, Puebla. Los frutos se sometieron a dos temperaturas de almacenamiento (7 y 22°C), inoculados con 7 log10UFC/mL de E. coli (ECET). Se evaluaron algunas propiedades físico-químicas como color, firmeza, pH y °Brix. Además se determinó la relación del contenido de azúcares (glucosa, fructosa y sacarosa) y ácidos orgánicos (ácido ascórbico y ácido cítrico) con la sobrevivencia de E. coli (ECET) adherida a los pericarpios de frutos almacenados a 7 y 22°C. Los resultados mostraron la sobrevivencia de E. coli en ambas temperaturas de almacenamiento, siendo la temperatura de 22°C la que propicio significativamente el desarrollo de esta bacteria y por ende su adherencia al pericarpio de los frutos. Las propiedades físico-químicas se afectaron por la colonización de E. coli (ECET), particularmente en la luminosidad y la firmeza, independientemente de la temperatura de almacenamiento. La reducción de la firmeza fue mayor en frutos inoculados y almacenados a 22°C, en comparación con la obtenida en frutos expuestos a 7°C.La cromátida a* presento valores máximos a 22°C, influenciando significativamente los índices a*/b* y (a*/b*)2. La colonización y adherencia de E. coli (ECET) en la superficie del jitomate se favorecio por la cantidad de azúcares solubles totales presentes, siendo más alto el recuento de bacterias a temperatura ambiente (22°C), donde la cantidad de azúcares tambien fue mayor. La colonización y adherencia de ECET en la superficie del jitomate se relacionó con los factores intrínsecos como el contenido de azúcares solubles, y acumulación de ácido ascórbico, y del factor extrínseco: temperatura de almacenamiento, debido a que estos compuestos propician condiciones adecuadas para el desarrollo y adherencia de las bacterias. Se concluye que las condiciones de almacenamiento influyen diferencialmente sobre el crecimiento, adherencia de E. coli (ECET), así como en el color y firmeza de los frutos de jitomate. _______________ SAFETY AND QUALITY OF FRESH TOMATO (Lycopersicum esculentum L.) STORED AT DIFFERENT TEMPERATURES: RELATION OFSUGARS AND ORGANIC ACIDS WITH THE ADHESION OF Escherichia coli (ETEC). ABSTRACT: Safety is an important requirement for acceptance in tomato (Lycopersicum esculentum L.) to enable its trade in new markets. In order to be accepted into the latter, the fruit must meet certain quality standards related to its physical and chemical properties. The main aim of this study was to determine the physical and chemical properties of tomato fruit stored at different temperatures in the presence of Escherichia coli (ETEC). Tomato fruits of Charleston variety were used, grown in greenhouse under hydroponics in the Municipality of Aquixtla, Puebla. The fruits were stored at 7 and 22°C, inoculated with 7 log10CFU/mL E. coli (ETEC). Several physical-chemical properties such as color, strength, pH and °Brix were evaluated. The relation of sugar contents (glucose, fructose and sucrose) and organic acids (ascorbic acid and citric acid) with the survival of E. coli (ETEC) attached to the pericarp of fruits stored at 7 and 22°C was also determined. The results showed the survival of E. coli at both storage temperatures; being the temperature of 22°C the most significantly suitable for the development of this bacteria, and thus its adherence to the pericarp of the fruit. The physical-chemical properties were affected by colonization of E. coli (ETEC), particularly in the luminosity and firmness, regardless of the storage temperature. Firmness reduction was greater in fruits inoculated and stored at 22°C, compared to that obtained in fruits exposed to 7°C. Chromatid a* presented maximum values at 22°C, significantly influencing the a*/b* and (a*/b*)2 indexes. Colonization and adhesion of E. coli (ETEC) in the surface of tomatoes was favored by the amount of total soluble sugars present, the count of bacteria was higher at room temperature (22°C), wherein the amount of sugars was also higher. The colonization and adherence of ETEC on the surface of tomatoes was associated with intrinsic factors such of soluble sugars, and ascorbic acid accumulation and the extrinsic factor of storage temperature, because these compounds enable conditions for the development and adherence of the bacteria. We conclude that storage conditions differentially influence on growth, adherence of E. coli (ETEC) and the color and firmness of tomato fruit.

Master thesis

Azúcares Acidos orgánicos Adherencia Lycopersicum esculentum Adherence Organic acids Sugars Estrategias para el Desarrollo Agrícola Regional EDAR CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA