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Efecto de la fertilización con azufre en la cebolla de rama (Allium fístulosum L.), en el municipio de Carmen de Carupa, Cundinamarca.

Cabezas Gutiérrez, Marco; Lora Silva, Rodrigo; Rojas Clavijo, Jeimer Raul; Morales Sandoval, Erwin Ademir (Bogotá : Universidad de Ciencias Aplicadas y Ambientales, 2005, 2005-07)

ln order to evalúate two sources and four doses of sulfur for production and econom ic benefit of Alium fístulosum, an experiment was carried out at the plateau of Carmen de Carupa (Cundinamarca). The fertilizers, ammonium ...
Estudio de barbechos en el páramo la cumbrera y su Relación con la recuperación del suelo.

Limas Cano, Luis Fernando; Estupiñan, Luis Hernando; Zenner De Polania, Ingeborg (Bogotá : Universidad de Ciencias Aplicadas y Ambientales, 2002, 2002-11)

To perceice the dynamism of tallows at different sucessive stages at the paramo La Cumbrera (Oriental hills of Bogotá, Colombia), relationships between changes in time of the physical and Chemical soil characteristics were ...
Evaluación de insecticidas no convencionales para el control de Aphis gossypii Glover (Hemiptera: aphididae) en fríjol

Peña, Manuel J.; Castro, Julio C.; Soto, Alberto (Bogotá : Universidad de Ciencias Aplicadas y Ambientales, 2013, 2013-01)

La concentración letal (CL) es usada para estimar la toxici-dad de pesticidas a artrópodos; sin embargo, la CL es una medida incompleta de los efectos de los productos sobre poblaciones, pues analiza solamente ...
Nature of the Active Sites of Molybdenum-Based Catalysts and Their Interaction with Sulfur- and Nitrogen-Containing Molecules Using the Quantum Theory of Atoms in Molecules and the Molecular Electrostatic Potentia

Aray, Yosslen (2019)

Density-functional theory (DFT), morphologic, and quantum theory of atoms in molecules (QTAIM) studies of bilayer models of nonhydrogenated MoS2, CoMoS, and NiMoS phases have been performed. The QTAIM calculations have ...
Respuesta de la papa criolla (solanum phureja juz et buk) a la aplicación de nitrógeno y azufre en el departamento de Cundinamarca (Colombia)

Lora Silva, Rodrigo; Guerrero Riascos, Ricardo; Sánchez M., Mario Enrique; Fierro E., Boris (Bogotá : Universidad de Ciencias Aplicadas y Ambientales, 2000, 2000-12)

The creole potato (Solanum phureja Juz et Buk) is planted in an important area of Colombia. It is accepted by the people due to its nutritive value and culinary qualities and has a good export potential to Europe, Japan. ...

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Efecto de la fertilización con azufre en la cebolla de rama (Allium fístulosum L.), en el municipio de Carmen de Carupa, Cundinamarca.
...
Cabezas Gutiérrez, Marco | 2005-07

ln order to evalúate two sources and four doses of sulfur for production and econom ic benefit of Alium fístulosum, an experiment was carried out at the plateau of Carmen de Carupa (Cundinamarca). The fertilizers, ammonium sulfate and calcium sulfate were tested, at the rate of 25, 50, 75 and lOOkg/ha of sulfur, using a divided plot design, where the main plot corresponded to the sulfur source and the secondary one to the dosage. In each main plot an absolute check, without sulfur, was employed and at the end the average data were calculated in order to make the respective comparisons. The experimental unit consisted in five rows, of four meters length each, for a total of 56 plants. Yield components, number of bunches per plant, individual bunch weight and fresh plant weight were evaluated. Plant dry matter was also determined and a cost benefit analysis of the fertilizer application was realized. It was demonstrated that under the experimental conditions the use of calcium sulfate proved to be better than ammonium sulfate regarding the total yield, while the treatments with ammonium sulfate contributed to an important increase of the dry matter percentage of the plant. The most favorable cost benefit analysis not necessarily coincided with the mayor gain margin, wherefore it is recommended to use 50 and 75kg of sulfur, in the form of calcium sulfate to obtain an agronomic and economic optimal profit.

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Estudio de barbechos en el páramo la cumbrera y su Relación con la recuperación del suelo.
...
Limas Cano, Luis Fernando | 2002-11

To perceice the dynamism of tallows at different sucessive stages at the paramo La Cumbrera (Oriental hills of Bogotá, Colombia), relationships between changes in time of the physical and Chemical soil characteristics were established. The main purpose was to determine, if the rest periods really correspond to a recuperation, or whether the alterations persist. The relation between the age of the fallow was evaluated, evaluated, taking into account indicators of soil alterations and recuperations. According to the results it was found, the at the paramo La Cumbrera, no realtionship exists among soil texture and fallow age. On the other hand, organic matter contents for large and for short rest periods were always high, neither ¡mportant changes in potassium and magnesium contents were observed. Sulfur, ¡ron copper and boron contents remained, showing an increase through time. It was concluded that even in tallows 50 years oíd, the alterations caused by the agricultura! use of the paramo persist.

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Evaluación de insecticidas no convencionales para el control de Aphis gossypii Glover (Hemiptera: aphididae) en fríjol
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Peña, Manuel J. | 2013-01

La concentración letal (CL) es usada para estimar la toxici-dad de pesticidas a artrópodos; sin embargo, la CL es una medida incompleta de los efectos de los productos sobre poblaciones, pues analiza solamente la mortalidad, como parámetro de toxicidad. Se sabe que individuos que sobrevi-ven a la exposición a pesticidas pueden sufrir efectos suble-tales. En este trabajo fue estudiado en laboratorio los efec-tos letales y subletales del caldo sulfocálcico, Azadirachta indica (Bioneem®) y Allium sativum-Capsicum chinense(Alisin®) en el crecimiento poblacional de A. gossypii y el efecto fitotóxico de estos insecticidas sobre plantas de frí-jol.Los efectos letales fueron estimados a través de test de toxicidad aguda con obtención de curvas dosis-respuesta y sus respectivas concentraciones letales y los efectos subleta-les, a través de la estimativa de la tasa instantánea de creci-miento poblacional (ri). Las concentraciones letales (CL95) y subletales (CL50) del Caldo sulfocálcico fueron 0,64 y 0,25% del producto, respectivamente, para el Bioneem®,de1,22y 0,71% del producto, y para el Alisin®, de 2,18 y 0,94% del producto, lo que indica que se podrían utilizar para el control del fitófago. No se presentaron síntomas graves de fitotoxi-cidad sobre las plantas asperjadas. El manejo de A. gossypii en fríjol es posible de ser realizado con los productos Caldo sulfocálcico, Bioneem® y Alisin®.

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Nature of the Active Sites of Molybdenum-Based Catalysts and Their Interaction with Sulfur- and Nitrogen-Containing Molecules Using the Quantum Theory of Atoms in Molecules and the Molecular Electrostatic Potentia
...
Aray, Yosslen | 2019

Density-functional theory (DFT), morphologic, and quantum theory of atoms in molecules (QTAIM) studies of bilayer models of nonhydrogenated MoS2, CoMoS, and NiMoS phases have been performed. The QTAIM calculations have shown that for inactive catalysts, such as MoS2 and Ni3S2, the basins of the outermost atoms of the particles on the exposed surfaces are almost covered by S atomic basins, giving reduced access to the Ni and Mo atoms. In contrast, for very active catalysts, such as NiMoS and RuS2, there are substantial open zones on the outermost S basin, giving considerable access to the metal atoms. Analysis of the electrostatic potential mapping onto the outermost atoms basins reveals soft Lewis acid zones for Ni3S2 and MoS2 and strong Lewis acid zones for NiMoS and RuS2. QTAIM and electrostatic potential calculations on hydrated MoS2-based monolayers have shown that the adsorption strengths (binding energies) of sulfur (H2S, thiophene, dibenzothiophene) and nitrogen (NH3 and acridine) compounds on the exposed metallic sites are related to the Lewis basic-acid interaction of the minima at the molecule and the maxima at the metallic sites, whereas on the so-called BRIM sites, it is the result of the combination of Lewis and Brønsted acidity. The studied nitrogen and sulfur molecules exhibit just one and two lone pairs on the N and S atoms, respectively. In general, N minima ≫ S minima, showing the origin of the larger adsorption of the organonitrogen molecules, except on those metallic sites where both sulfur lone pairs adsorb at two neighboring metal maxima. The present results corroborate and explain the origin of the reported DFT findings.

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Respuesta de la papa criolla (solanum phureja juz et buk) a la aplicación de nitrógeno y azufre en el departamento de Cundinamarca (Colombia)
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Lora Silva, Rodrigo | 2000-12

The creole potato (Solanum phureja Juz et Buk) is planted in an important area of Colombia. It is accepted by the people due to its nutritive value and culinary qualities and has a good export potential to Europe, Japan. United States and Canada. Nitrogen and Sulphur play an important role in yield and quality. Therefore the present research was developed, having as objectives to determine the effect of nitrogen and sulphur applications on tuber yield, quality and protein content, the establishment of the most adequate N/S relationship in petioles and to perform an economic evaluation of the results. The research was developed on an Hapludand soil at 2850 m.a.s.L, 11°C mean temperature, 85% relative humidity. 13% organic matter content, alofane presence, median to low available sulphur content. loamy sand texture, pH 4.85 and an adecuate Ca:Mg:K relationship. A completely randomized block design in factorial arrangement was utilized. Nitrogen levels employed were 0-40-80-120 Kg N/ha and sulphur levels were 0-20-40-60 Kg S/ha. The sources used were amonion nitrate with 30% nitrogen and calcium sulphate with 16% sulphur. The results showed a significative response in total yield and tuber size. The highest yield, compared with the check (1.8 t/ha) was 24 t/ha. Protein content was found to be related to an adecuate quantity and relationship of nitrogen and sulphur fertilization. With the use of 120 Kg M/ha and 20 Kg S/ha the tuber protein of 6% was obtained, while the check tuber protein reached only 3.5%. The best M/S relationship in the petiole was 16:1. Taking intoaccountthe potato price and the cost of fertilizers each peso ($) inverted in nitrogen and sulphur returned $ 87.

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Browsing by Subject "Azufre"

Efecto de la fertilización con azufre en la cebolla de rama (Allium fístulosum L.), en el municipio de Carmen de Carupa, Cundinamarca. ﻿

Estudio de barbechos en el páramo la cumbrera y su Relación con la recuperación del suelo. ﻿

Evaluación de insecticidas no convencionales para el control de Aphis gossypii Glover (Hemiptera: aphididae) en fríjol ﻿

Nature of the Active Sites of Molybdenum-Based Catalysts and Their Interaction with Sulfur- and Nitrogen-Containing Molecules Using the Quantum Theory of Atoms in Molecules and the Molecular Electrostatic Potentia ﻿

Respuesta de la papa criolla (solanum phureja juz et buk) a la aplicación de nitrógeno y azufre en el departamento de Cundinamarca (Colombia) ﻿

Envíos recientes

Efecto de la fertilización con azufre en la cebolla de rama (Allium fístulosum L.), en el municipio de Carmen de Carupa, Cundinamarca.

Estudio de barbechos en el páramo la cumbrera y su Relación con la recuperación del suelo.

Evaluación de insecticidas no convencionales para el control de Aphis gossypii Glover (Hemiptera: aphididae) en fríjol

Nature of the Active Sites of Molybdenum-Based Catalysts and Their Interaction with Sulfur- and Nitrogen-Containing Molecules Using the Quantum Theory of Atoms in Molecules and the Molecular Electrostatic Potentia

Respuesta de la papa criolla (solanum phureja juz et buk) a la aplicación de nitrógeno y azufre en el departamento de Cundinamarca (Colombia)

Efecto de la fertilización con azufre en la cebolla de rama (Allium fístulosum L.), en el municipio de Carmen de Carupa, Cundinamarca.

Estudio de barbechos en el páramo la cumbrera y su Relación con la recuperación del suelo.

Evaluación de insecticidas no convencionales para el control de Aphis gossypii Glover (Hemiptera: aphididae) en fríjol

Nature of the Active Sites of Molybdenum-Based Catalysts and Their Interaction with Sulfur- and Nitrogen-Containing Molecules Using the Quantum Theory of Atoms in Molecules and the Molecular Electrostatic Potentia

Respuesta de la papa criolla (solanum phureja juz et buk) a la aplicación de nitrógeno y azufre en el departamento de Cundinamarca (Colombia)