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Gold recovery from very dilute solutions from a mine in closing process: adsorption-desorption onto carbon materials

ESMERALDA VENCES ALVAREZ ELIAS RAZO FLORES Isabel Lázaro ROBERTO BRIONES GALLARDO GUILLERMO VELASCO MARTINEZ JOSE RENE RANGEL MENDEZ (2017)

"The aurocyanide complex recovery by precipitation with zinc decreases when gold concentration drops to < 20 μg L− 1. Therefore, a technology capable of recovering gold from very diluted solution is necessary. Adsorption and desorption experiments were carried out with real solutions in batch and in continuous processes to determine the gold adsorption capacity and rate onto two activated carbons (AC). The results showed that AC F400 and CSC removed 86 and 81 μg g− 1, respectively, at pH 11 and Ce of 10 μg L− 1 in about 4 h. Whereas desorption test by NaOH and CN− showed a gold recovery of up to 86%. These experiments were correlated to the textural and chemical properties of adsorbents and to the chemical composition of samples from a heap leach process. AC is a highly efficient and selective adsorbent for gold cyanide solutions when gold is present in very low concentration (< 12 μg L− 1)."

Article

Gold cyanide Activate carbons Adsorption Desorption Packed bed column BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA FÍSICA

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

Producción de huevo en cafetales: una opción de diversificación productiva

Manuel Sánchez Sánchez (2015)

Tesis (Maestría en Ciencias, especialista en Innovación Agroalimentaria Sustentable).- Colegio de Postgraduados, 2015.

En México alrededor de tres millones de personas dependen directa o indirectamente del café; cuyo cultivo en los últimos tres años ha sido afectado, en más del 80 %, por la roya del cafeto (Hemileia vastatrix Berkeley & Broome). Por lo anterior, la presente investigación tuvo el objetivo de evaluar la producción de huevo como una opción de diversificación productiva en cafetales. La población inicial del experimento fue de cinco gallos y 44 gallinas, ambos híbridos de las razas Rhode Island – Araucana, de cuatro semanas de edad. Se utilizó un gallinero con cama profunda y fueron pastoreadas por 12 horas en un cafetal de 1352 m2, sembrado a una densidad de 5000 plantas por hectárea con café (Coffea arabica L) de la variedad Oro Azteca. La evaluación a las gallinas se realizó durante un año de postura. Los resultados indican que la actividad es sustentable; con una relación beneficio /costo de 1.35, una producción promedio de 174 huevos por semana. El análisis físico químico de las heces indicaron que las aves aportaron al cafetal N t 4.85 %, P 1.77 %, K 1.41 % entre otros nutrientes, los cuales representan el 55 % de los nutrientes extraídos en una tonelada de café cereza. _______________ EGG PRODUCTION IN COFFEE PLANTATIONS: AN OPTION OF PRODUCTIVE DIVERSIFICATION. ABSTRACT: In Mexico around three million people depend directly or indirectly coffee; whose cultivation in the past three years has been affected by more than 80% for leaf rust (Hemileia vastatrix Berkeley & Broome). Therefore, the present study aimed to evaluate the production of egg as an option for diversification in coffee. The initial population of the experiment was 44 five cocks and hens hybrid races both Rhode Island - Araucana, four weeks old. A chicken with deep litter was used and were grazed for 12 hours in a coffee plantation of 1352 m2, planted at a density of 5000 plants per hectare with coffee of the variety Aztec gold. The evaluation was performed chickens a year in posture. The results indicate that the activity is sustainable; with a benefit / cost ratio of 1.35, an average production of 174 eggs per week. The physical and chemical analysis of feces indicated that birds contributed to cafetal N t 4.85%, 1.77% P, K 1.41% from other nutrients, which represent 55% of the nutrients removed in a ton of coffee cherry.

Master thesis

Agropastoril Cama profunda Gallus domesticus L. Innovación Coffea arabica Deep bed Innovation Innovación Agroalimentaria Sustentable Maestría CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Definition of critical hydrodynamic conditions for sediment motion initiation using optical technique

JUAN ANTONIO GARCIA ARAGON CARLOS DIAZ DELGADO KLEVER IZQUIERDO AYALA HUMBERTO SALINAS TAPIA (2016)

Sediment motion initiation experiments were performed in a glass rectangular channel, with a loose bed in the central part. The main goal is to obtain the critical hydrodynamic characteristics that causes sediment bed motion initiation, for different cohesionless sediment grain sizes. The optical technique of Particle Tracking Velocimetry (PTV) was used in order to determine the critical velocity profiles for sediment initiation of motion. Between the parameters that define this critical velocity profile is the one known as bed rugosity which represents the height of asperities in the bed. For conditions near bed motion initiation experimental velocity profiles were obtained and they allowed us also to define fluctuating velocities u´, v´ and a value of bed rugosity ks related to a representative grain size of the bed. It was shown that obtained critical velocity profiles are in good agreement with other works in the scientific literature provided an appropriate definition of bed rugosity is made.

Universidad Autónoma del Estado de México

Article

non-cohesive sediments motion initiation bed rugosity critical velocity profile PTV INGENIERÍA Y TECNOLOGÍA

Sand waves generation: a numerical investigation of the Infiernillo Channel in the Gulf of California

YOVANI MONTAÑO LEY JOSE NOEL CARBAJAL PEREZ (2016)

"The effect of the coastal geometry on sand bed forms generation has been investigated for a tidal dominated area. Different hypothetical geometries of coastal channels with flat bottoms and unlimited sediment availability were exposed to strong oscillatory tidal currents to simulate the interaction of hydrodynamics and the bedload sediment transport. The hypothetical geometries stand for the idealization of the principal geographic features of the Infiernillo Channel, a coastal area of the Gulf of California where sandbanks and sand waves have been observed. A depth integrated hydrodynamic-numerical model and a parameterized formula to estimate the bedload sediment transport were applied coupled with a sediment conservation equation to determine the sea bottom morphodynamics. Model predictions in the Infiernillo Channel were compared to available satellite imagery. This investigation demonstrates that a vertical integrated numerical model is able to reproduce the development of incipient sand waves that exist in the Infiernillo Channel. Incipient sandbanks and shoals were also simulated. Sand waves with wavelengths of about 200 m were calculated on the same locations where sand waves actually exist. A crucial finding of this research was to show that the geometry of a shallow water basin and the presence of tidal velocity gradients associated with abrupt changes in the coastline alignment were critical in determining the sand-bed pattern generation. We demonstrate that a vertical variation of tidal currents is not necessary to generate sand waves."

Article

Sand waves Tidal hydrodynamics Bed load Sediment transport CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Effect of bed planting and zero tillage on productivity and water use of Irrigated maize - wheat cropping system in Khyber Pakhtunkhwa province of Pakistan

Imtiaz Hussain Muhammad Imtiaz (2018)

Crop establishment methods like broadcasting of wheat and manual planting of maize on flat surface coupled with flood irrigation are used in irrigated maize–wheat system of Khyber Pakhtunkhwa (KP) province that requires skilled labor, intensive tillage and more water for irrigation. In this study, zero tillage and bed planting effect in comparison with farmer practice on maize-wheat system productivity was evaluated at five sites in district of Nowshera, KP province during 2014-2016. Maize grain yield with bed planting and manual planting on flat surface were non-significantly different. Because of weed infestation, there was 30 percent lower maize grain yield with zero till planted maize in comparison with bed planting and farmer practice. Zero till drill planted wheat after maize crop had higher grain yield in comparison with mechanized bed planting and farmer practice of broadcasting in 2014-15 and 2015-16 wheat season. Because of higher maize grain yield, maize–wheat system productivity was significantly higher with bed planting and farmer practice in comparison with Zero tillage. Bed planting of maize had 20 – 30 percent higher water use efficiency (WUE) in comparison with flat planting of farmer practice in both the years. Overall comparison of maize – wheat cropping system showed that there were 16 and 22 percent water saving with bed planting in comparison with other practice in 2014-15 and 2015-16 cropping cycle, respectively. The study showed that farmer practice of manual planting of maize and broadcasting of wheat can be replaced with bed planting of maize and zero till drill planting of wheat, respectively to save water, labor and improve maize-wheat system productivity and water use efficiency.

Article

Maize Wheats Zero tillage Pakistan Bed Planting Maize-Wheat System MAIZE ZERO TILLAGE WHEAT WATER USE EFFICIENCY YIELD AGRICULTURAL SCIENCES AND BIOTECHNOLOGY CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Characterization of a Capsicum chinense seed peptide fraction with broad antibacterial activity

LIGIA GUADALUPE BRITO ARGAEZ FERNANDO FEDER MOGUEL SALAZAR FERNANDO ZAMUDIO ZUÑIGA TOMAS GONZALEZ ESTRADA IGNACIO RODRIGO ISLAS FLORES (2009)

Habanero chili pepper (Capsicum chinense) is widely consumed as a fresh vegetable, although its extremely high capsaicin content has led to other uses (e.g., medicine and self-defense). Recently described antimicrobial peptides from C. annuum were very efficient in inhibiting growth in human and plant pathogenic bacteria and fungi. In order to explore the potential use of Capsicum chinenseseeds as a source of antimicrobial peptides, in the present study a peptide fraction from C. chinense pepper seeds, denominated G10P1, was enriched, partially purified and its antimicrobial activitytested against the plant and human pathogens Xanthomonas campestris, Pseudomonas syringae, Pseudomonas aeruginosa, Erwinia carotovora, Agrobacterium sp., Shigella flexnerii, Escherichia coli, Staphyllococcus aureus and Bacillus subtilis. The minimum inhibitory concentration of the G10P1 peptide fraction against X. campestris was 12.5 μg mL-1. Electrophoresis of the G10P1 in a denaturant 15% polyacrylamide gel showed it to be composed of ~7.57 and ~5.6 kDa polypeptides, both associated with an area of strong antibacterial activity. The sequencing of 18 amino acids from the N-terminal of the ~7.57 peptides and 12 from the ~5.6 kDa peptides showed no clear association with previously described antimicrobial peptides. However, the ~5.6 kDa peptides were related to the NAC and WRKY transcription factors, both involved in direct regulation of the plant defense response against pathogen attack and the ~7.57 kDa peptides had low homology with a 3-oxo-[acyl-carrier-protein] synthase from Capsicum chinense.

Article

ANTIMICROBIAL PEPTIDES CAPSICUM CHINENSE COLUMN CHROMATOGRAPHY HABANERO PEPPER PLANT ANTIMICROBIAL PEPTIDES BIOLOGÍA Y QUÍMICA

Effect of selective anthelmintic treatments on health and production parameters in Pelibuey ewes during lactation

JAVIER ARECE GARCIA YOEL LOPEZ LEYVA ROBERTO GONZALEZ GARDUÑO GLAFIRO TORRES HERNANDEZ ROLANDO ROJO RUBIO CARINE MARIE MAGDELEINE (2015)

A study was conducted from December to April 2013, with the aim of evaluating a system of selective antiparasitic treatments using the FAMACHA© color chart compared with a conventional suppressive deworming system every 30 days in Pelibuey ewes during lactation. For the study, 54 ewes were used. They were randomly divided into two groups: FAMACHA and chemical treatments. The ewes in the first group received selective treatment depending on the ocular mucosa coloration (FAMACHA) and body condition score (BCS), while in the second group (chemical) all the animals remained under routine deworming every 30 days. Fecal nematode egg counts, proportion of third-stage trichostrongylid larvae, body condition, coloration of the ocular mucosa, and packed cell volume in the ewes were determined, while in lambs only body weight (BW) was recorded. No significant differences (p>0.05) were observed in any of the studied variables between groups; however, the use of antiparasitic drugs was reduced during the experimental period in the FAMACHA group and no deaths of lambs or ewes were recorded. The results indicate that during the lactation of ewes, a strategy of selective treatments can be implemented without showing deterioration in major health and productive parameters of these animals.

cuba

Article

haemonchus contortus famacha© . pelibuey nematode control packed cell volume antiparasitic drug CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Removal of indigo carmine by a Ni nanoscale oxides/Schoenoplectus acutus composite in batch and fixed bed column systems

SALVADOR SANCHEZ RODRIGUEZ Jesica Trujillo Reyes Edith Eriela Gutiérrez Segura Marcos José Solache Ríos ARTURO COLIN CRUZ (2015)

Removal behavior of indigo carmine by Schoenoplectus acutus and Ni nanoscale oxides/Schoenoplectus acutus composite was determined. The characterization of both materials was done by TEM, SEM/EDS, DRX, and BET. Experimental data were best fitted to pseudo second order and Langmuir-Freundlich models for kinetics and isotherm, respectively; these results indicate a chemisorption mechanism on heterogeneous materials. Adsorption capacity of Ni nanoscale oxides/Schoenoplectus acutus composite was high in comparison with other adsorbents (760 mg/g). Adsorption of dye is not affected by pH (3 to 9). Metal nanoparticles supported on cheap and eco-friendly adsorbents are an alternative for the removal of dyes from wastewater.

Article

Indigo carmine Ni nanoscale oxides Shoenoplectus acutus Fixed bed columns BIOLOGÍA Y QUÍMICA

Análisis del comportamiento de la Radiación Eritemal UV y su relación con la Columna Total de Ozono reportada por OMI en el Estado de Zacatecas

MARIA DE LOS ANGELES LIZETH SOLIS JIMENEZ (2018)

The atmosphere is essential in the nature of the Earth, it is a layer of gases that, among other things, allows the temperature of the Earth to be hospitable to all living species. The interaction of solar radiation on the surface of the Earth and in the atmosphere has been the sum importance throughout the evolution of the Earth. Solar radiation is the source of energy that induces a diversity of natural phenomena, of enormous proportions, and a large number of these phenomena, is produced by photons of solar radiation of very specific wavelengths, such as photosynthesis and reactions of photodisociation. The photodissociation of Oxygen at high altitudes gives rise to Ozone formation. Ozone, despite being a trace of gas that represents less than 0.00001% in the atmosphere, plays an important and irreplaceable role because it attenuates UV-B and UV-A radiation to relatively harmless levels for living beings.

For this reason, to know the tendencies of the behavior of the erythema UV radiation and its relation with the Total Ozone Column is great importance. This work includes the systematization and analysis of the behavior of the erythematous dose in the State of Zacatecas from the end of 2005 to the beginning of 2006, data provided by NASA. The systematization found is indicative of the erythematous dose levels that may occur in the State throughout the year.

La atmósfera es esencial en la naturaleza de la Tierra, es una capa de gases que, entre otras cosas, permite que la temperatura de la Tierra sea hospitalaria para todas las especies vivientes. La interacción de la radiación solar en la superficie de la Tierra y en la atmósfera ha sido de suma importancia a lo largo de la evolución de la Tierra. La radiación solar es la fuente de energía que induce una diversidad de los fenómenos naturales, de enormes proporciones, y un gran número de estos fenómenos, se produce por fotones de radiación solar de longitudes de onda muy específicos, tales como la fotosíntesis y las reacciones de fotodisociación. La fotodisociación del Oxígeno en grandes altitudes da lugar a la formación del Ozono. El Ozono, a pesar de ser un gas traza que en la atmósfera representa menos del 0.00001%, cumple un importante e insustituible papel pues atenúa la radiación UV-B y UV-A hasta niveles relativamente inofensivos para los seres vivos.

Por este motivo, conocer las tendencias del comportamiento de la radiación eritemal UV y su relación con la Columna Total de Ozono es de suma importancia. Este trabajo comprende la sistematización y análisis del comportamiento de la dosis eritematosa en el Estado de Zacatecas de fines del 2005 a principios del 2006, datos proporcionados por la NASA. La sistematización encontrada es indicativa de los niveles de dosis eritematosa que puede ocurrir en el Estado a lo largo del año.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Master thesis

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Radiación Eritemal UV Columna Total de Ozono OMI Erithemal UV radiation Total Ozone Column