Sample records for ESTRUCTURA INTERSTICIAL (pore structure)
from WorldWideScience.org

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1

EFECTO DEL CAMBIO DE USO EN LA ESTABILIDAD DE LA ESTRUCTURA Y LA FUNCIÓN DE LOS POROS DE UN ANDISOL (TYPIC HAPLUDAND) DEL SUR DE CHILE/ Effect of Land Use on Structural Stability and Pore Functions of an Andisol (Typic Hapludand) in Southern Chile

Dörner, José; Dec, Dorota; Peng, Xinhua; Horn, Rainer
2009-01-01

Resumen en español Los suelos volcánicos del sur de Chile constituyen cerca del 60% del suelo arable del país. Estos suelos se encuentran bajo un amplio rango de usos desde sistemas prístinos hasta otros con un uso intensivo. El objetivo de este trabajo fue determinar el efecto del cambio de uso de suelo sobre: i) la estabilidad del suelo frente a presiones externas e internas; ii) la conductividad hidráulica y iii) su resiliencia funcional. Muestras disturbadas y no disturbadas de suel (mas) o fueron recolectadas a 5, 20, 40 cm de profundidad en un suelo Andisol (Typic Hapludand) bajo un renoval de bosque nativo (NF), una pradera de 50 años (P50) y otra de 1 año de uso (Pl). Se determinó la curva de retención de agua, contracción y consolidación, la conductividad hidráulica saturada (Ks), permeabilidad de aire (Ka), contenidos de carbono orgánico (CO), textura y alofán. Se estimó la conductividad hidráulica no saturada (Ku) de acuerdo al modelo propuesto por van Genuchten (1980). Se definieron índices de deformación de suelo como consecuencia de estreses mecánicos (COELm) e hidráulicos (COELh). El suelo estudiado está sujeto a constantes cambios en su estructura como consecuencia de estreses mecánicos e hidráulicos afectando la distribución de los poros y su funcionalidad. La magnitud de estos cambios disminuye con el incremento de la intensidad de uso del suelo. La gran capacidad de contracción del suelo puede traer consecuencias en su comportamiento hidráulico dependiendo de la intensidad del secado a través de la formación de grietas y vías de flujo de preferencial. Finalmente, los poros del suelo son capaces de recuperar su integridad funcional después de una compactación, lo que está estrechamente relacionado con los contenidos de materia orgánica Resumen en inglés Volcanic soils in southern Chile cover approximately 60% of the arable land in the country. These soils are under a wide range of land uses from pristine systems to intensively used ones. The objective of this study was to determine the effect of the land use change on: i) the structural stability after external and internal forces, ii) the hydraulic conductivity and iii) its functional resilience. Disturbed and undisturbed soil samples were collected at 5, 20 and 40 cm d (mas) epths in an Andisol (Typic Hapludand) under native forest (NF), 50 year old pasture (P50) and 1 year old pasture (PI). The water retention, shrinkage and consolidation curves, hydraulic conductivity (Ks), air permeability (Ka), organic carbon content (CO), soil texture and allophane contents were determined. The unsaturated hydraulic conductivity (Ku) was estimated according to van Genuchten (1980). Soil deformation indexes as a consequence of mechanical (COLEm) and hydraulic (COLEh) stresses were calculated. The studied soil is subject to continuous changes in their structure as a consequence of mechanical and hydraulic stresses affecting the pore size distribution and its functionality. The magnitude of these changes decreased with the increasing intensity of the land use. The great shrinkage capacity of the soil may have consequences on its hydraulic behaviour depending on the drying intensity through the formation of cracks and preferential path flows. Finally, the soil pores are able to recover its functional integrity after compaction, which is strongly related to the presence of organic matter contents

Scientific Electronic Library Online (Spanish)

2

Morphology, Histology and Histochemistry of the Venom Apparatus of the Centipede, Scolopendra valida (Chilopoda, Scolopendridae)/ Morfología, Histología e Histoquímica del Aparato Venenoso del Ciempiés, Scolopendra valida (Chilopoda, Scolopendridae)

Jarrar, Bashir M
2010-03-01

Resumen en español Fueron investigadas las características morfológicas, histológicas e histoquímicas del aparato venenoso del ciempiés, S. valida. El aparato venenoso de Scolopendra valida consta de un par de maxilopodos y glándulas de veneno situadas anteriormente en el prosoma, a cada lado del primer segmento del cuerpo. Cada glándula de veneno se continúa en una garra con una cavidad tubular que posee una punta afilada y un poro subterminal situado sobre la curvatura externa. El (mas) epitelio glandular es plegado y se compone de una masa de epitelio secretor, cubierto por una vaina de los músculos estriados. El epitelio secretor consiste en células columnares altas productoras de veneno con gránulos citoplasmáticos de veneno densos. El conducto glandular carece de musculatura y está revestido por capa interna quitinosa y epitelio cuboidal simple. Los resultados histoquímicos indican que las células productoras de veneno de ambas glándulas elaboran glucosaminoglucanos mucosustancias ácidas, ciertos aminoácidos y proteínas, pero carecen de glucógeno. La estructura y las secreciones de las glándulas de veneno del ciempiés son examinadas en el contexto de los presentes resultados Resumen en inglés Morphological, histological and histochemical characterizations of the venom apparatus of the centapede, S. valida have been investigated. The venom apparatus of Scolopendra valida consists of a pair of maxillipedes and venom glands situated anteriorly in the prosoma on either side of the first segment of the body. Each venom gland is continuous with a hollow tubular claw possessing a sharp tip and subterminal pore located on the outer curvature. The glandular epithelium (mas) is folded and consists of a mass of secretory epithelium, covered by a sheath of striated muscles. The secretory epithelium consists of high columnar venom-producing cells having dense cytoplasmic venom granules. The glandular canal lacks musculature and is lined with chitinous internal layer and simple cuboidal epithelium. The histochemical results indicate that the venom-producing cells of both glands elaborate glycosaminoglycan, acid mucosubstances, certain amino acids and proteins, but are devoid of glycogen. The structure and secretions of centipede venom glands are discussed within the context of the present results

Scientific Electronic Library Online (Spanish)

3

LA PERMEABILIDAD DEL AIRE Y CONDUCTIVIDAD HIDRÁULICA SATURADA COMO HERRAMIENTA PARA LA CARACTERIZACIÓN FUNCIONAL DE LOS POROS DEL SUELO/ Air permeability and saturated hydraulic conductivity as a tool for the functional characterization of soil pores

Dorner, José; Dec, Dorota
2007-01-01

Resumen en español Con el objetivo de describir los aspectos funcionales de los poros de suelos labrados, se recolectaron muestras no disturbadas en dos profundidades y orientaciones (vertical y horizontal) en suelos estructurados del Norte de Alemania. Se determinó la curva de retención de agua, la permeabilidad de aire (ka) y la conductividad hidráulica en fase saturada (k f). Se calculó la distribución de poros por tamaño, la porosidad de aire e índices de continuidad de poros. El (mas) manejo agrícola afecta al suelo cuantitativa y cualitativamente. La formación de un pie de arado implica no tan sólo una reducción del volumen de poros sino que también causa una dependencia espacial de las propiedades hidráulicas del suelo a través de la formación de una estructura laminar. Con el objeto de establecer dichos cambios cualitativos, mediciones como ka y k f son una buena herramienta para describir la calidad física del suelo Resumen en inglés In order to describe the pore functions of ploughed soils, undisturbed soil samples were collected at two depths and orientations (vertical and horizontal) in structured soils in the Weichselian moraine region in Northern Germany. The water retention curve, air permeability (ka) and saturated hydraulic conductivity (k f) were measured. The pore-size distribution, air-filled porosities and pore continuity indices were calculated. The tillage affects the soil quantitatively (mas) and qualitatively. The tillage-induced ploughed pan not only implies a reduction of the pore volume but also causes a direction-dependent behaviour of hydraulic properties through the development of a platy structure. In order to assess these qualitative changes, measurements like ka and/or k f are a good tool to describe the physical quality of a soil

Scientific Electronic Library Online (Spanish)

4

Porosidad de los yacimientos naturalmente fracturados: una clasificación fractal/ Porosity in naturally fractured media: A fractal classification

Miranda-Martínez, Ma. Eugenia; Oleschko, Klaudia; Parrot, Jean-Francois; Castrejón-Vacio, Fernando; Taud, Hind; Brambila-Paz, Fernando
2006-01-01

Resumen en español El movimiento y la distribución de fluidos a través de los medios porosos están determinados por su geometría. La naturaleza autosimilar de la estructura de estos medios ha sido el objeto de numerosos estudios que han documentado las relaciones de potencia ('power law') entre las principales medidas de poros y sólidos, y la resolución del método utilizado para su análisis. En la presente investigación se introduce un esquema fractal para clasificar los yacimiento (mas) s naturalmente fracturados (YNF) a partir de imágenes de tomografía computarizada de rayos X. Esta clasificación tiene como propósito extraer y medir algunos rasgos geométricos de los poros tanto a nivel global (firmagrama), como local (líneas de referencia) vía los clasificadores fractales. Los clasificadores fractales, extraídos de las imágenes digitales, fueron útiles para hacer un diagnóstico simple y rápido del tipo de porosidad de un núcleo a partir de su imagen. La dimensión fractal de masa (Dm y ), la dimensión espectral ofractón (),el exponente de Hurst (H) y la lagunaridad (Λ) de los YNF del sureste de México, son estadísticamente diferentes para los tres patrones de porosidad representativos de estos materiales: fracturas, cavidades y porosidad mixta. Para estimar los primeros dos (Dm y ), es necesario presegmentar la imagen en conjuntos de poros y sólidos, creando una imagen binaria, previo a la cuantificación fractal. En los últimos (H y Λ), la extracción de los parámetros se realiza directamente a partir de las imágenes originales evitando el proceso de segmentación, lo que permite proponer a los clasificadores H y Λ como estimadores más confiables de la porosidad de los YNF. Todos los clasificadores fractales, y en especial la dimensión fractal de masa y la lagunaridad de los tres patrones de porosidad arriba especificados, mostraron una correlación estadísticamente significativa con la porosidad (medida con técnicas tradicionales) de las capas geológicas con distinta capacidad productora de hidrocarburos. Este hecho abre un nuevo panorama para la modelación y pronóstico de la geometría de los YNF. Resumen en inglés The flow and distribution of fluids through pores in porous media are governed by their geometry. The self-similar behavior of the structure of these sets has been the subject of numerous studies that have documented the power laws relationship, among the principal measures of pores and solids, and the resolution of the method used for their analysis. A fractal scheme is introduced in order to extract and measure some geometric features of pores, using the mean values of (mas) their fractal classifiers, dividing these in global (ftrmagram) and local (reference line) classifiers. The mass fractal dimension (Dm), the spectral dimension orfracton (), the Hurst exponent (H) and the lacunarity (Λ) of naturally fractured reservoirs (YNF) of southeastern Mexico, have shown to be statistically different for the three most representative porosity sets: fractures, cavities and mixed porosity. The fractal classifiers, extracted from digital images obtained using X-ray computerized tomography, were useful for porosity classification in different patterns, starting from the core images. Dm and must be determined on presegmented images, which distinguish the pore and solid sets, prior to the fractal quantification, while H and Λ can be extracted from the original image, which drastically diminishes the bias in the porosity estimation. All fractal classifiers, including mass dimensions and lacunarity of the porosity patterns specified above for YNF, showed a statistically significant correlation with the porosity of the geological strata as determined by traditional techniques. All our results offer new perspectives for the modeling and forecasting of porosity in the naturally fractured deposits.

Scientific Electronic Library Online (Spanish)

5

Water Storage in the Lichen Family Umbilicariaceae

Valladares, Fernando; Sancho, Leopoldo G.; Ascaso, Carmen
1998-01-01

Digital.CSIC (Spain)

6

Waste-derived activated carbons for removal of ibuprofen from solution: Role of surface chemistry and pore structure

Mestre, Ana S.; Pires, João; Nogueira, José M. F.; Parra Soto, José Bernardo; Carvalho, Ana P.; Ovín Ania, M.ª Concepción

7 pages, 4 figures, 3 tables. -- PMID: 19006666 [PubMed]. -- Available online 8 November 2008. | The removal of a widespread used drug (i.e., ibuprofen) from water was investigated using high valuable carbon adsorbents obtained from chemical and physical activation of a bioresource (cork) and a muni...

DRIVER (Spanish)

7

Waste-derived activated carbons for removal of ibuprofen from solution: Role of surface chemistry and pore structure

Mestre, Ana S.; Pires, João; Nogueira, José M. F.; Parra Soto, José Bernardo; Carvalho, Ana P.; Ovín Ania, M.ª Concepción
2009-03-01

Digital.CSIC (Spain)

8

Using DFT analysis of adsorption data of multiple gases including H2 for the comprehensive characterization of microporous carbons

Jagiello, J.; Ovín Ania, M.ª Concepción; Parra Soto, José Bernardo; Jagiello, L.; Pis Martínez, José Juan
2007-04-01

Digital.CSIC (Spain)

9

Treatment of rising damp and salt decay: the historic masonry buildings of Adelaide, South Australia

López-Arce, Paula; Doehne, Eric; Greenshields, J.; Benavente, David; Young, D.
2008-09-26

Digital.CSIC (Spain)

10

Trapping and adsorption of CO2 in amorphous ice: A FTIR study

Gálvez, Óscar; Maté, Belén; Herrero, Víctor J.; Escribano, Rafael
2008-06-06

Digital.CSIC (Spain)

11

Titanium-Containing Zeolites and Microporous Molecular Sieves as Photovoltaic Solar Cells

Atienzar Corvillo, Pedro; Valencia, Susana; Corma, Avelino; García Gómez, Hermenegildo
2007-04-05

Digital.CSIC (Spain)

12

Thermal analysis of merino wool fibres without internal lipids

Martí Gelabert, Meritxell; Manich, Albert M.; Coderch Negra, M. Luisa; Parra Juez, José Luis
2007-06-25

Digital.CSIC (Spain)

13

The Large Electrochemical Capacitance of Microporous Doped Carbon Obtained by Using a Zeolite Template

Ovín Ania, M.ª Concepción; Khomenko, Volodymyr; Raymundo-Piñero, Encarnación; Parra Soto, José Bernardo; Béguin, François
2007-06-18

Digital.CSIC (Spain)

14

Templated synthesis of nanosized mesoporous carbons

Álvarez García, Sonia; Valdés-Solís Iglesias, Teresa; Fuertes Arias, Antonio Benito
2008-07-01

Digital.CSIC (Spain)

15

Synthesis, Characterization and Catalytic Applications of Organized Mesoporous Aluminas

Márquez-Alvarez, C.; Zilková, N.; Pérez-Pariente, J.; Čejka, J.
2008-04-02

Digital.CSIC (Spain)

16

Synthesis of large pore zeolites and zeotypes

Camblor, Miguel Ángel; Corma Canós, Avelino; Villaescusa, Luis A.; Díaz Cabañas, María José
2000-08-03

Digital.CSIC (Spain)

17

Support for enzymes and proteins comprising an inorganic solid combined material comprising the support.

Corma Canós, Avelino; Fornés, Vicente; Jordá Moret, José Luis; Rey García, Fernando; Fernández Lafuente, Roberto; Guisán Seijas, José Manuel; Mateo, Cesar
2001-08-24

Digital.CSIC (Spain)

18

Study of color and structural changes in silver painted medieval glasses

Pérez-Villar, Sofía; Rubio, Juan; Oteo Mazo, José Luis
2007-01-01

Digital.CSIC (Spain)

19

Structure of the Hsp110:Hsc70 Nucleotide Exchange Machine

Schuermann, Jonathan P.; Jiang, Jianwen; Cuéllar, Jorge; Llorca, Óscar; Wang, Liping; Giménez, Luis E.; Jin, Suping; Taylor, Alexander B.; Demeler, Borries; Morano, Kevin A.; Hart, P. John; Valpuesta, José M.; Lafer, Eileen M.; Sousa, Rui
2008-06-12

Digital.CSIC (Spain)

20

Structural determinants of Kvbeta1.3-induced channel inactivation: a hairpin modulated by PIP2

Decher, Niels; González, Teresa; Streit, Anne Kathrin; Sachse, Frank B.; Renigunta, Vijay; Soom, Malle; Heinemann, Stefan H.; Daut, Jürgen; Sanguinetti, Michael C.
2008-11-06

Digital.CSIC (Spain)

21

Structural Analysis of the Laetiporus sulphureous Hemolytic Pore-forming Lectin in Complex with Sugars

Mancheño, José M.; Hiroaki, Tateno; Goldstein, Irwin J.; Hermoso, Juan A.
2005-04-29

Digital.CSIC (Spain)

22

Protein and water structural changes in fish surimi during gelation as revealed by isotopic H/D exchange and Raman spectroscopy

Sánchez González, Ignacio; Carmona, Pedro; Moreno, Pilar; Borderías, A. Javier; Sánchez Alonso, Isabel; Rodríguez-Casado, Arantxa; Careche, Mercedes
2008-01-01

Digital.CSIC (Spain)

23

Process for preparing multilayers with and ordered mesoporous structure, material obtained in this manner, and use

Míguez García, Hernán Ruy; Soler Illia Galo, Juan de Avila; Fuertes, María Cecilia; López Alcaráz, Javier
2008-03-27

Digital.CSIC (Spain)

25

Preparation of Ni-doped carbon nanospheres with different surface chemistry and controlled pore structure

Zubizarreta, Leire; Arenillas de la Puente, Ana; Pis Martínez, José Juan

8 pages, 9 figures, 2 tables.-- Available online on Dec 27, 2007. | In classic carbon supports is very difficult to control pore size, pore size distribution, and surface chemical properties at the same time. In this work microporous carbons derived from furfuryl alcohol are used as support to prepa...

DRIVER (Spanish)

26

Preparation of Ni-doped carbon nanospheres with different surface chemistry and controlled pore structure

Zubizarreta, Leire; Arenillas de la Puente, Ana; Pis Martínez, José Juan
2008-04-30

Digital.CSIC (Spain)

27

Porous crystal structures obtained from directionally solidified eutectic precursors.

Larrea Arbáizar, Ángel; Orera Clemente, Víctor Manuel
2007-03-15

Digital.CSIC (Spain)

29

Plasma Membrane-porating Domain in Poliovirus 2B Protein. A Short Peptide Mimics Viroporin Activity

Madan, Vanesa; Sánchez-Martínez, Silvia; Vedovato, Natascia; Rispoli, Giorgio; Carrasco, Luis; Nieva, José L.
2007-09-26

Digital.CSIC (Spain)

30

Photonic crystals with anomalous dispersion: Unconventional propagating modes in the photonic band gap

Hermann, D.; Diem, M.; Mingaleev, S.F.; García-Martín, Antonio; Woelfle, P.; Busch, K.
2008-01-11

Digital.CSIC (Spain)

33

On Estimating Concrete Porosity by Ulrasonic Non-Destructive Testing

Vergara, L.; Miralles, R.; Gosálbez, J.; Juanes, F. J.; Gómez-Ullate Alvear, Luis; Anaya Velayos, José Javier; González Hernández, Margarita; García Izquierdo, Miguel Ángel
2001-09-01

Digital.CSIC (Spain)

34

New insights on the use of supercritical carbon dioxide for the accelerated carbonation of cement pastes

García-González, Carlos A.; El Grouh, Nadia; Hidalgo, Ana; Julio Fraile, Julio; López-Periago, Ana M.; Andrade, Carmen; Domingo, Concepción
2008-01-01

Digital.CSIC (Spain)

35

Métodos de END mediante ultrasonidos para caracterizar la durabilidad del mortero

Vergara, L.; Miralles, R.; Gosálbez, J.; Juanes, F. J.; Gómez-Ullate Alvear, Luis; Anaya Velayos, José Javier; González Hernández, Margarita; García Izquierdo, Miguel Ángel
2000-10-01

Digital.CSIC (Spain)

36

Molecular determinants of stereoselective bupivacaine block of hKv1.5 channels

Franqueza, Laura; Longobardo, Mónica; Vicente, Javier; Delpón, Eva; Tamkun, Michael M; Tamargo, Juan; Snyders, Dirk J.; Valenzuela, Carmen
1997-11-01

Digital.CSIC (Spain)

37

Modificaciones inducidas por la adición de puzolanas naturales zeolíticas en las pastas de cemento

Blanco Varela, M.ª Teresa; Martínez-Ramírez, Sagrario; Gener, Marta; Vázquez Moreno, Tomás
2005-12-30

Digital.CSIC (Spain)

38
39

Metakaolin sand–blended-cement pastes: Rheology, hydration process and mechanical properties

Janotka, I.; Puertas, F.; Palacios, M.; Kuliffayová, M.; Varga, C.
2010-05-01

Digital.CSIC (Spain)

40

Mesoporous structures having high catalytic activity in acid catalysis reactions and preparation method thereof

Agúndez Rodríguez, Javier; Díaz Carretero, Isabel; Márquez Álvarez, Carlos; Pérez Pariente, Joaquín; Sastre de Andrés, Enrique
2004-05-13

Digital.CSIC (Spain)

41

Membranas cerámicas. Tipos, métodos de obtención y caracterización

Benito, J. M.; Conesa, A.; Rodríguez Barbero, Miguel Ángel
2004-09-01

Digital.CSIC (Spain)

42

Influence of porosity and fissuring on coking pressure generation

Casal Banciella, M.ª Dolores; Barriocanal Rueda, Carmen; Díez Díaz-Estébanez, M.ª Antonia; Álvarez García, Ramón
2008-04-10

Digital.CSIC (Spain)

43

Importance of the Hydrophobic Character of Activated Carbons on the Removal of Naphthalene from the Aqueous Phase

Ovín Ania, M.ª Concepción; Cabal Álvarez, Belén; Parra Soto, José Bernardo; Pis Martínez, José Juan
2007-04-01

Digital.CSIC (Spain)

44

Highly active structured catalyst made up of mesoporous Co3O4 nanowires supported on a metal wire mesh for the preferential oxidation of CO

Marbán Calzón, Gregorio; López Suárez, Irene; Valdés-Solís Iglesias, Teresa; Fuertes Arias, Antonio Benito
2008-10-11

Digital.CSIC (Spain)

45

Growth of carbon nanofilaments on coal foams

Calvo Díez, Montserrat; Arenillas de la Puente, Ana; García Fernández, Roberto; Rodríguez Moinelo, Sabino J.
2009-01-01

Digital.CSIC (Spain)

48

Evolución microestructural durante la transformación de la estructura pirocloro en perovskita en láminas de (Pb,La)TiO3

Algueró Giménez, Miguel; Calzada Coco, María Lourdes; Pardo Mata, Lorena; Drazic, G.; Kosec, M.
2002-02-01

Digital.CSIC (Spain)

50

Evaluación de la estructura porosa de los materiales MCM-22, MCM-36 e ITQ-2 empleando el test catalitico del n-decano/ Evaluation of the pore structure of MCM-22, MCM-36 and ITQ-2 materials using the n-decane catalytic test

Pergher, Sibele B. C.; Corma, Avelino; Fornés, Vicente
2003-12-01

Resumen en inglés The void structure of zeolites MCM-22, MCM-36 and ITQ-2 were discussed on the bases of catalytic reaction tests. The hydromerization of n-decane on bifunctional Pt/Zeolite Catalysts have been used as model reactions. Beta and ZSM-5 zeolites were used for comparison. It is concluded that all materials show features of 10MR zeolites and have also pores bigger than 12MR in this order MCM-22

Scientific Electronic Library Online (Spanish)

51

Effects of aging and drying conditions on the structural and textural properties of silica gels.

Estella, Juncal; Echeverría, Jesús C.; Laguna, Mariano; Garrido, Julián J.
2007-05-01

Digital.CSIC (Spain)

52

Effects of activated carbon properties on the adsorption of naphthalene from aqueous solutions

Ovín Ania, M.ª Concepción; Cabal Álvarez, Belén; Pévida García, Covadonga; Arenillas de la Puente, Ana; Parra Soto, José Bernardo; Rubiera González, Fernando; Pis Martínez, José Juan
2007-04-30

Digital.CSIC (Spain)

55

Efecto de la adición de lodos de papel activados térmicamente en las propiedades mecánicas y de porosidad de pastas de cemento.

Rodríguez Largo, Olga; Sánchez de Rojas, María Isabel; Frías, M.; García, R.; Vigil, R.
2009-04-17

Digital.CSIC (Spain)

57

Dynamics of soil hydraulic properties during fallow as affected by tillage

Moret Fernández, David; Arrúe Ugarte, José Luis
2007-06-08

Digital.CSIC (Spain)

58

Durability improvement of ancient bricks by cementation of porous media

López-Arce, Paula; Benavente, David; García Guinea, Javier
2005-06-08

Digital.CSIC (Spain)

59

Deterioration of dolostone by magnesium sulphate salt: An example of incompatible building materials at Bonaval Monastery, Spain

López-Arce, Paula; García Guinea, Javier; Benavente, David; Tormo, Laura; Doehne, Eric
2008-05-12

Digital.CSIC (Spain)

61

Correlation between heats of immersion and limiting capacitances in porous carbons

Álvarez Centeno, Teresa; Fernández López, José Antonio; Stoeckli, F.
2008-03-14

Digital.CSIC (Spain)

62

Control of the structural properties of mesoporous polymers synthesized using porous silica materials as templates

Fuertes Arias, Antonio Benito; Sevilla Solís, Marta; Álvarez García, Sonia; Valdés-Solís Iglesias, Teresa
2008-07-01

Digital.CSIC (Spain)

63
65

Comparison by SEM, TEM, and EIS of hydrothermally sealed and cold sealed aluminum anodic oxides

López, V.; Bartolomé, Mª. J.; Escudero, E.; Otero, Eduardo; González, J. A.
2006-01-25

Digital.CSIC (Spain)

66

Coal-Based Carbon Foams. Influence of the Precursor Coal

Calvo Díez, Montserrat; García Fernández, Roberto; Rodríguez Moinelo, Sabino J.

DRIVER (Spanish)

67

Coal-Based Carbon Foams. Influence of the Precursor Coal

Calvo Díez, Montserrat; García Fernández, Roberto; Rodríguez Moinelo, Sabino J.
2007-01-01

Digital.CSIC (Spain)

68

Characteristics of high heating rate biomass chars prepared under N2 and CO2 atmospheres

Gómez Borrego, Ángeles; Garavaglia, L.; Kalkreuth, W. D.
2009-01-31

Digital.CSIC (Spain)

69

Carbon materials for H2 storage

Zubizarreta, Leire; Arenillas de la Puente, Ana; Pis Martínez, José Juan
2008-09-14

Digital.CSIC (Spain)

70

CARBONO ORGÁNICO Y PROPIEDADES DEL SUELO/ Soil organic carbon and soil properties

Martínez H, Eduardo; Fuentes E, Juan Pablo; Acevedo H, Edmundo
2008-01-01

Resumen en español El carbono orgánico del suelo (COS) se relaciona con la sustentabilidad de los sistemas agrícolas afectando las propiedades del suelo relacionadas con el rendimiento sostenido de los cultivos. El COS se vincula con la cantidad y disponibilidad de nutrientes del suelo, al aportar elementos como el N cuyo aporte mineral es normalmente deficitario. Además, al modificar la acidez y la alcalinidad hacia valores cercanos a la neutralidad, el COS aumenta la solubilidad de var (mas) ios nutrientes. El COS asociado a la materia orgánica del suelo proporciona coloides de alta capacidad de intercambio catiónico. Su efecto en las propiedades físicas se manifiesta mediante la modificación de la estructura y la distribución del espacio poroso del suelo. La cantidad de COS no solo depende de las condiciones ambientales locales, sino que es afectada fuertemente por el manejo del suelo. Existen prácticas de manejo que generan un detrimento del COS en el tiempo, a la vez hay prácticas que favorecen su acumulación. En este trabajo se discute la relación entre carbono orgánico, propiedades químicas, físicas, biológicas y el manejo del suelo. Además se plantean metodologías para estudiar los flujos de C0(2) del suelo a la atmósfera Resumen en inglés Soil organic carbon (SOC) is related to the sustainability of the agricultural systems affecting soil properties linked to crop yield. SOC affects the amount and availability of soil nutrients, contributing elements as N, usually deficient. In addition, SOC modify the acidity and the alkalinity towards values near the neutrality, and then it increases the solubility to several nutrients. SOC associated to the soil organic matter provides colloids having high cation exchan (mas) ge capacity. Its effect on the physical properties of the soil is reflected in the soil structure and pore size distribution. SOC concentration depends on the local environmental conditions, but it is also affected strongly by the soil management practices. There are managements that decrease SOC and viceverse other practices that favor the accumulation. The present review deals with the influence of SOC on the chemical, physical, biological properties of the soil and how it is affected by soil management. We also describes methodologies to study C0(2) fluxes from soil to atmosphere

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71

Borderline microporous-ultramicroporous palladium(II) coordination polymer networks. Effect of pore functionalisation on gas adsorption properties

Navarro, Jorge A. R.; Barea, Elisa; Salas, Juan M.; Masciocchi, Norberto; Galli, Simona; Sironi, Angelo; Ovín Ania, M.ª Concepción; Parra Soto, José Bernardo
2007-02-23

Digital.CSIC (Spain)

73

Band formation from coupled quantum dots formed by a nanoporous network on a copper surface

Lobo-Checa, Jorge; Matena, Manfred; Müller, Kathrin; Dil, Jan Hugo; Meier, Fabian; Gade, Lutz H.; Jung, Thomas A.

4 pages, 3 figures.-- Supporting information (Materials and Methods, SOM Text, Suppl. figs. S1-S7, Suppl Refs, 15 pages) available at: http://science-mag.aaas.org/cgi/data/325/5938/300/DC1/1 | The properties of crystalline solids can to a large extent be derived from the scale and dimensionality of ...

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74

Band formation from coupled quantum dots formed by a nanoporous network on a copper surface

Lobo-Checa, Jorge; Matena, Manfred; Müller, Kathrin; Dil, Jan Hugo; Meier, Fabian; Gade, Lutz H.; Jung, Thomas A.; Stöhr, Meike
2009-07-17

Digital.CSIC (Spain)

75

Bacterially-Mediated Authigenesis of clays in Phosphate Stromatolites

Sánchez-Navas, A.; Martín Algarra, A.; Nieto, F.
1998-05-01

Digital.CSIC (Spain)

76

Arena metacaolínica. Material prometedor como adición al cemento Portland

Janotka, I.; Puertas, F.; Palacios, M.; Varga, C.; Krajči, L.
2010-01-01

Digital.CSIC (Spain)

77

Adsorption of naphthalene from aqueous solution on activated carbons obtained from bean pods

Cabal Álvarez, Belén; Budinova, Temenuzhka; Ovín Ania, M.ª Concepción; Tsyntsarski, Boyko; Parra Soto, José Bernardo; Petrova, Bilyana
2009-01-30

Digital.CSIC (Spain)

78

A Zeolite Structure (ITQ-13) with Three Sets of Medium-Pore Crossing Channels Formed by 9- and 10-Rings

Corma, Avelino; Puche, Marta; Rey García, Fernando; Sankar, Gopinathan; Teat, Simon J.

Final full-text version of the paper available at Angewandte Chemie International Edition website: http://dx.doi.org/10.1002/anie.200390304.-- Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2003/z50514_s.pdf or from the author.-- Corrig...

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79

A Zeolite Structure (ITQ-13) with Three Sets of Medium-Pore Crossing Channels Formed by 9- and 10-Rings

Corma, Avelino; Puche, Marta; Rey García, Fernando; Sankar, Gopinathan; Teat, Simon J.
2003-03-10

Digital.CSIC (Spain)

80

Estructuras de deformación (¿sismitas?) en la Formación Río Negro, provincia de Río Negro, Argentina

Schillizzi, Roberto; Luna, Liliana; Falco, Juan Ignacio
2010-07-01

Resumen en español A Las estructuras de deformación (ED) en sedimentos blandos comprenden las alteraciones que se producen casi simultáneamente con la sedimentación. Estos procesos se hallan en relación directa con las características internas de los materiales sedimentarios y de los factores externos que actúan sobre ellos. Sus resultados incluyen deformaciones como inyecciones, fracturas, volcanes y laminaciones convolutas que afectan total o parcialmente la estratificación. Los se (mas) dimentos blandos deformados por sismos se incluyen bajo la denominación general de sismitas (seismites). Como objetivo de esta investigación se plantea reconocer, por primera vez, estructuras de deformación ubicadas en la Formación Río Negro presentes en el sector norte del Golfo San Matías, en inmediaciones del Faro Río Negro. La metodología empleada consistió en el reconocimiento y descripción de las estructuras, para lo cual se extrajeron muestras para determinar granulometría, mineralogía y contenido de materia orgánica. Se fotografiaron los distintos sectores con deformaciones con el fin de establecer modelos comparativos. El sector estudiado, de 4 km de extensión, se ubica entre el faro de Río Negro y el inicio del Banco Verde y morfológicamente corresponde a un frente acantilado con orientación ENE-OSO. En él se determinaron las siguientes ED: a- de carga simple, pseudonódulos contiguos y aislados, y estructuras complejas; b- de escape de fluidos y c- estructuras de deslizamiento basal y por presión dirigida. El origen de las deformaciones se debe a las características de las sedimentitas y a los procesos que las afectan tales como los efectos por carga, escapes de fluidos y las presiones dirigidas. Como origen de estos procesos se señalan: la presión de la columna litológica, las olas de tormentas y los terremotos. Por los rasgos hallados las deformaciones del litoral rionegrino tendrían un origen sísmico, proceso ocurrido en un único evento durante el ciclo Andino cuyos inicios se fijan hace aproximadamente 45 Ma. Por otra parte sus techos y bases no se hallan asociados a otros procesos de deformación y sus espesores no exceden el metro de potencia. Además se hallan acotadas a la zona de transición entre los miembros medio y superior de la Formación Río Negro descansando en algunos casos sobre arcilitas y en otros sobre limolitas, originadas en un paleorelieve de interdunas. Resumen en inglés Soft-sediment deformation structures (SSD) are alterations produced almost simultaneously with sedimentation. They are directly related to internal characteristics of sedimentary materials as well as to external factors acting on them. Results derived from such alterations are evidenced as injections, fractures, volcanoes and convolute laminations, among other forms, affecting stratification either totally or partially. Soft-sediment deformation structures resulting from (mas) seisms are known as seismites. The present study aims at determining for the first time the presence of SSD structures in the Río Negro Formation, located in the northern area of San Matías Gulf, near Río Negro Lighthouse, Argentina (Fig. 1). To this end, structures were firstly identified and further described. Samples were subsequently collected for the determination of grain-size, mineralogy and organic matter content. Photographs of the different sectors evidencing deformations were taken in order to determine further comparative models. Morphology in the study area is associated to cliffs with vertical, fractured fronts and with an average height of 70 m in whose base torn-down blocks are accumulated. The geological structure of the study area is related to the Cuenca del Colorado and the Comarca Nordpatagónica, whose basement is mainly composed of Paleozoic and Mesozoic crystalline rocks. The sedimentary tertiary cover from the Miocene-Pliocene is represented by light-blue sandstones of the Río Negro Formation (Andreis, 1965). This unit was formed in an aeolian environment with intercalations of clay-silt shallow lagoons and a marine episode located in the mid area of the Río Negro Formation. At the top of the Río Negro Formation there are Pleistocene-Holocene sedimentites having a thickness of up to 5 m. Within the local structural framework of our study area there are fractures with a NE-SW and a NW-SE direction, which are related with fractures N55º, N90º and N350º azimuth located in the abrasion platform. According to Dzulinsky and Walton (1965), Lowe (1975), Brencley and Newall (1977), Clauss (1993), van Loon (2002), Owen (2003), Neuwerth et al. (2006), Alfaro et al. (2006), Montenat et al. (2007), among others (Table 1), and, taking into account the geometry of deformations, laboratory reconstructions and field observations from our study area, it can be concluded that the classifications of SSD structures tend to establish morphologic and genetic systematizations. The following characteristics were identified in our study area: limited deformations among stratigraphic horizons; a lateral continuity of SSD structures at considerable distances; and a confinement between non-deformed strata and its lithological association with psamitic-pelitic sediments. The study area, which is 4 km long and is located between Río Negro Lighthouse and the beginning of Banco Verde, is from the morphological point of view, a cliffed front with an ENE-WSW orientation. Different types of SSD structures were identified in this area. For example, from the morphological point of view and according to the loading mechanisms observed, simple-load structures (Fig. 2), attached and detached pseudonodules (Figs. 3, 4 and 5) and complex structures (Fig. 6) were identified. Furthermore, from the genetic point of view and according to the intrusion processes observed in soft sediments, water-scape structures (Fig. 7) and plate- or fountain-like deformations (Fig. 8) were found. From the genetic point of view, and based on the collapse and pressure mechanisms observed, basal slumping (Fig. 9) and directed-pressure structures (Fig. 11) were also found. The above-mentioned SSD structures were analyzed and interpreted following Strachan´s model (2002) (Fig. 10) and Laird´s model (1968) (Fig. 12). The origin of SSD structures depends on the characteristics of sedimentites and on the mechanisms that produce them. In the study area, the materials susceptible to deformation come from an interdune environment that is characterized by granulometric variations derived from the fluctuating and restrictive climatic conditions (Cojan and Thiry, 1992) that typify the Río Negro Formation. Fine-grained materials having low cohesion and poor sorting such as the sediments of deformed strata (Fig. 13) produced SSD structures as a result of high pore pressure and liquefaction effects (Tsuchida and Hayashi, 1971; Obermeier, 1996). Grain packing with a porous value as that allows intercommunication among grains and saturated material, is also crucial to the formation of SSD structures. The mineralogic content of deformed levels is composed of i) quartz, chalcedony, orthose, plagioclase, pyroxenes and biotite, opaques (magnetite and ilmenite, autigenic pyrite) in crystalline aggregates; ii) undetermined Fe oxides; and iii) colorless and light-brown unaltered volcanic glass shards, clays identified as smectite-illite interstratified and scarce kaolinite. Grains are mainly subangular and, to a lesser extent, sub-round and round. The surface of the majority of grains in the study area was found clean and with some marks. The percentage of CaCO3 was found to vary from 0.5 to 3% and that of total organic carbon (TOC) was found to reach 1.5%. Deformations may be produced as a result of load deformation mechanisms, fluid escape, basal slumping or pressure-directed displacements. Due to load deformation mechanisms, structures are linked to gravity-related movements occurring during the initial stages of deposition. For these deformations to occur, grain-size at the overlaying levels should be thicker than at the underlying levels, for example, sandstones rather than silstones or claystones. These deformations are related to water saturation at the deformed level (fluidization-liquefaction). Therefore, deformation mechanisms, which involve both expulsion and rotation of fragments as well as fluid escape, are characterized by the action of lithostatic pressure which produces movement (deformation) and by the action of the underlying sedimentary levels. Deformations may also result from a fluid escape mechanism, i.e., from a mechanism associated to i) the spatial arrangement of grains (packing), ii) their shape, iii) their tendency to inequigranularity, and iv) the communication among macro- and micro- pores as well as the high or low sinuosity connection among themselves (Net and Limarino, 2000). Further requirements for deformations to occur include particular thixotrophic conditions, especially the presence of colloids among grains. The rupture of unions of particles either by hitting or by shearing is, among others, a cause which produces an unbalance between hydrostatic pressure and lithostatic pressure. If the latter is altered, the energetic unbalance makes fine sediments flow among the weakly lithified sandstones whose extrusion will occur via both vertical and horizontal pore ducts (Lopez Gamundi, 1986; Clauss, 1993). Basal slumping produces deformations that are associated not only to soft sediments deposited in natural slopes but also to interbedded sand- and mud-levels. Layers tend to have a prismatic-shaped geometry whose materials are under ductile-to-fragile conditions, in which antique layers support younger ones. Once horizontality is affected, movement, which is marked by a rupture of the original slope, begins. The lower levels are expected to transport the upper ones without affecting the original succession of layers. At the delay of movement derived from the compressive effect of the displacement front, fluids extrude forming cones or cut dikes (Fig. 10). Several deformations of this type initiate movement as result of differences in the hydrostatic gradient (Strachan, 2002). Deformations may be also produced as a result of pressure-directed displacements which are conditioned by the compaction level, thickness and ability of materials to deform. Thus, deformations occur because the original level is saturated in water as a result of the ductile behavior of materials (Bracco et al., 2005). Laird (1968) claims that SSD structures should meet some of the following requirements to be considered of seismic origin: slightly curved strata walls and floors to follow the original stratification and interruption of continuity of the stratum that is marked by a scar in which the sedimentary fillings keep their characteristics both above and below stratification. There could be rotated sediment clasts below the discontinuity as a result of a thrust-induced drag of the upper sedimentary packing. These processes could be, in turn, triggered either by the charge or pressure of the lithologic column, storm waves and seismicity. Storm-wave impact may also produce deformation in soft sediments. Nonetheless, no high energy structures such as cross-beddings or tsunami-type chaotic sedimentation were observed in our study area. Noteworthingly, for stormwave-derived liquefaction to occur, waves should reach magnitudes higher than 6 m (Alfaro et al., 2002), this being a phenomenon that was not recorded in our study area. Taken together, findings from the present study indicate that SSD structures in our study area are seismic alterations that occurred in an event during the Andean cycle whose beginnings are traced approximately 45 My ago. The fact that i) both the roofs and bottoms of these structures are not associated to other processes of deformation, ii) their thickness does not exceed one meter, and iii) they are confined to a transitional area between the middle and top members of the Río Negro Formation, lying in some cases on claystones and in some other cases, on siltstones, originated in an interdune paleorelief, confirms their seismic origin.

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81

Estructura y porosidad de recubrimientos híbridos de SiO2

Durán Carrera, Alicia Amparo; Gallardo Serra, Ivonne Janet; Galliano, P.
2001-01-01

Digital.CSIC (Spain)