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Microchemical identification of macael white marble in some spanish monuments
Bello, M. A.,Martin, L.,Martin, A.
Materiales de Construccion , 1992,
Abstract: The white marble from Macael quarries (Almería, Spain) has been identified in some monuments of the Southern of Spain; the use of other white marble types has also been confirmed. The microchemical identification has been carried out by means a previously described graphical method (Bello and Martín,1991). Fourteen trace elements have been analyzed from both quarry and building material samples by using atomic absorption and flame emission spectrometry in order to apply the enrichment diagrams for trace elements (EDTE) for identification purposes. Ha sido confirmado el empleo del mármol blanco procedente de las canteras de Macael (Almería) en varios monumentos del Sur de Espa a; también se ha constatado el empleo de otros tipos de mármol blanco. La identificación del mármol de Macael mediante técnicas microquícas ha sido realizada mediante un método gráfico propuesto por los autores (1). Han sido analizados catorce elementos traza en las muestras de cantera y de los edificios mediante espectrofotometría de absorción atómica y de emisión de llama, al objeto de construir los diagramas de enriquecimiento de elementos traza (EDTE), con fines de identificación.
Performance of Spanish white Macael marble exposed to narrow- and medium-range temperature cycling
Rodríguez Gordillo, J.,Sáez Pérez, M. P.
Materiales de Construccion , 2010,
Abstract: White marble specimens from Macael in the Spanish province of Almeria were exposed to narrow- (50/20 oC) and medium- (100/-20 oC and 75/-20 oC) range thermal stress cycles. The effects were monitored with ultrasound techniques. Ultrasound velocity declined considerably in samples subjected to 100/-20 oC cycles, more moderately when the range was 75/-20 oC and insignificantly when it was narrowed to 50/-20 oC. All variations were recorded in the first five to seven cycles, with values flattening thereafter. The Schmidt hardness and compression test results concurred with the ultrasound findings. Petrographic and scanning electron microscope (SEM) imaging revealed some very superficial granular decohesion in the specimens subjected to forty 100/-20 oC cycles. The concurrent results from compression testing on the one hand and surface hardness and ultrasound measurements on the other confirmed the validity of the latter two nondestructive techniques (NDT) for determining the effects of thermal stress cycling on stone mechanical strength. Se aplican ciclos de estrés térmico de medio (100/-20 oC y 75/-20 oC) y bajo (50/-20 oC) rango sobre probetas de mármol blanco de Macael (Almería, Espa a), y se evalúa ciclo a ciclo su incidencia mediante ultrasonidos. Los resultados indican un considerable descenso de velocidad de los ultrasonidos en las muestras sometidas a estrés de 100/-20 oC, más moderado en el caso de 75/-20 oC, poco significativo en el caso de 50/-20 oC. Las variaciones de velocidad tienen lugar durante los primeros ciclos (5-7), permaneciendo los valores constantes en ciclos posteriores. Los resultados proporcionados por medidas de dureza de Schmidt, y de rotura por compresión uniaxial son coincidentes con los proporcionados por los ultrasonidos. Las imágenes de microscopía petrográfica y electrónica (SEM) manifiestan una cierta descohesión granular en zonas muy superficiales de las probetas sometidas a 40 ciclos de 100/-20 oC. La coincidencia entre los datos por las técnicas de rotura por compresión, medidas de dureza superficial y ultrasonidos indican la validez de estas dos últimas —técnicas no destructivas, NDT— en el control de la incidencia de ciclos de stress térmico sobre las características mecánicas de materiales pétreos.
The thermophysical properties of serpentinite  [PDF]
Hr?ak, D.,Su?ik, G.,Lazi?, L.
Metalurgija , 2008,
Abstract: In this article serpentinite from Banovina, Croatia, was studied. The antigorite is main mineral constituent of that rock. The dilatation curve shows that the first contraction of sample is coursed by dehydratation of antigorite at nearly 660°C. In spite of this, the second contraction of sample, which begines at nearly 860°C, is incident with olivine phase formation. The morphology of the serpentinite before and after thermal treatment was observed with the optical microscope. Image of serpentinite before thermal treatment is characterized by inclusions of olivine as primary mineral left as residue in process of serpentinization. Image of serpentinite after thermal treatment was changed by water disappear. The first thermal treated and than milled serpentinite has better properties than the first milled and than thermally treated serpentinite.
Flora de los afloramientos de mármoles y serpentinitas de las Sierras de Córdoba (Argentina) Flora of marble and serpentinite outcrops of the Sierras de Córdoba (Argentina)
Juan José Cantero,Jorge A Sfragulla,César Nú?ez,Aldo A Bonalumi
Kurtziana , 2011,
Abstract: Los afloramientos rocosos constituyen hábitats importantes desde el punto de vista de conservación de la biodiversidad. En este trabajo se provee de un catálogo de las especies de plantas vasculares que crecen en los afloramientos cálcicos y dolomíticos (mármoles) y serpentinitas de la Sierra de Córdoba, se describe la variación composicional de su flora y se explora su relación litológico-geoquímica sobre la distribución de los grupos florísticos detectados. Treinta y uno (31) afloramientos fueron relevados en un área que se extendió en unos 280 km de latitud y 120 km de longitud (30° 42&#'; a 33° 5&#'; Lat. Sur y 64° 20&#'; a 65° 20&#'; Long. Oeste) y desde los 500 m.s.m hasta los 2000 m.s.m. El área promedio relevada en cada afloramiento fue de aproximadamente 2725 m2 en donde se realizó el inventario de todas las especies de plantas vasculares presentes, su colección y el muestreo litológico para la evaluación posterior de la geoquímica de las rocas. Se registraron 404 especies distribuidas en 67 familias y 255 géneros. Se mencionan 6 citas nuevas para la provincia. La endemoflora de los 31 afloramientos comprende 88 especies. La riqueza promedio de especies de los afloramientos fue de 68 y la diversidad promedio de H = 4,14. El total de especies medicinales relevadas en los afloramientos fue de 212. Las hemicriptófitas (52%), caméfitas (17 %), fanerófitas (16%) y geófitas (9 %) fueron las formas de vida predominantes. La composición florística a nivel regional, variable a lo largo del gradiente geográfico -y climático-, se sobre impuso a la variación local ambiental (geoquímica, altitud) entre los afloramientos. Se identificó un número mínimo de sitios a conservar que incluyen la máxima biodiversidad a través de los datos disponibles de riqueza, diversidad, número de especies endémicas, y rareza. Rock outcrops are important habitats for biodiversity conservation. This paper provides a catalog of species of vascular plants that grow on limestone (marble) and serpentinites of the Sierra de Córdoba, describing the compositional variation of its flora and exploring the lithological-geochemical control on the distribution of the floristic groups. Thirty-one (31) outcrops were surveyed in an area that extended about 280 km in latitude and 120 km in length (30 ° 42 &#';33 ° 5' Lat. South 64 ° 20 &#';65 ° 20' Long. West) and from 500 m.s.m. to 2000 m.s.m. The average sampling area in each outcrop was approximately 2725 m2 where the inventory of all vascular plant species and the lithological sampling for subsequent evaluation of the rock geochemistry were
Troodos: A Giant Serpentinite Diapir  [PDF]
Roelof Dirk Schuiling
International Journal of Geosciences (IJG) , 2011, DOI: 10.4236/ijg.2011.22010
Abstract: Troodos is a classical ophiolite complex. It is proposed that the serpentinized harzburgites that now form the top of the mountain and represent the originally lowest part of the ophiolite sequence rose as a diapir. This diapiric rise is caused by the pervasive serpentinization of a suboceanic harzburgite, due to rock-sea water interaction. The serpentinization caused a 44% expansion of the rocks. Contrary to salt diapirism, the driving force for this diapiric rise is not so much the difference in density, but the volume increase asscociated with the transformation of harzburgite into serpentinite. The overlying gabbros, sheeted dike complex and pillow lavas were pierced by this serpentinite diapir but barely deformed. Their interaction with sea water was li- mited to some pyroxenes in the gabbros being transformed to amphiboles, and epidotisation of some of the dikes in the sheeted dike complex. The location of steep faults in the Troodos massif is determined by the contrasting expansion behavior of different rock-types on both sides of the fault.
Serpentinite Slurries against Forest Fires  [PDF]
R. D. Schuiling
Open Journal of Forestry (OJF) , 2015, DOI: 10.4236/ojf.2015.53022
Abstract: Forest fires are one of the commonest natural hazards. Forest fires make the largest contribution to CO2 emissions after the burning of fossil fuels. Here a new technology is proposed to extinguish forest fires not with water, but with a slurry of serpentine. Serpentinites are abundantly available in many countries on every continent. If serpentine is calcined, it weathers very fast and captures CO2. Calcination, however, requires a lot of heat, which makes it counterproductive to produce calcined serpentine for CO2 capture. In cases, however, where heat is the problem, like in forest fires, one can extinguish them to greater advantage by using serpentinite slurries instead of plain water. The calcined residue that is left as a thin cake on the burning material prevents oxygen to reach the burning material. It also prevents the escape of inflammable gases, and the calcination itself withdraws large quantities of heat from the fire. After the fire is extinguished, the calcined material in contact with the atmosphere will rapidly weather and capture CO2. This compensates part of the CO2 that is produced by the fire. In tests, where the efficacy of quenching fires with serpentine slurries was compared to the effect of water, it turned out that serpentinite slurries performed far better.
The blue marble
Gregory A Petsko
Genome Biology , 2011, DOI: 10.1186/gb-2011-12-4-112
Abstract: The timing of the picture was auspicious, to say the least. The early 1970s marked the beginning of an era of environmental activism in the US, and the blue marble Earth photo, being the first ever taken of an illuminated face of the entire planet, rapidly became a symbol of the movement. It's easy to see why. Our whole planet suddenly, in this image, seemed tiny, vulnerable, and incredibly lonely against the vast blackness of the cosmos. It also seemed whole in a way that no map could illustrate. Regional conflict and petty differences could be dismissed as trivial compared with environmental dangers that threatened all of humanity, traveling together through the void on this fragile-looking marble.I had occasion to use this picture in a talk I gave recently, and it got me thinking about the power of images.The word 'iconic' is often used for pictures like this one, and it fits. The word means, of course, to be like an icon, which is a symbol that perfectly represents something other than just itself. The blue marble was an iconic image because it perfectly represented the human condition of living on an island in the universe, with all the frailty an island ecosystem is prey to. People are particularly moved by images, in part because we have evolved to have our visual system as our primary sensory input, but also because an image can be retained easily in the mind's eye, and so forms the stuff of memory. The right image, offered at the right time, can have effects far greater than those imagined by the one creating it.Consider another picture that changed the world: the famous photograph of the German dirigible Hindenburg bursting into flames on 6 May 1937, in the skies over the Lakehurst Naval Air Station in New Jersey. It was that photo, more than the scale of the disaster - 36 people were killed, mostly from jumping to escape the fire, but 62 survived by staying on board as the burning blimp floated to the ground - that spelled doom for the graceful zeppelins
Reduction in Harmonics in Marble Industry
PRAKASH SUNDARAM,SHIMI S.L.,DR. S.CHATTERJI
International Journal of Innovative Research in Science, Engineering and Technology , 2013,
Abstract: Lower order harmonic are major problems in industries in India. This will get worse due to the increasing number of lagging power factor induction motors and harmonic generated non linear loads. During survey of Udaipur, Rajasthan (India) investigator found the poor condition of power quality in large number of marble, soft stone and minerals industries and took one marble industry for investigation of the power quality due to harmonic content in power supply. After measurement in Arihant Marble industry, Udaipur, Rajasthan (India), the investigator found that the 5th harmonic content was beyond the IEEE limits. Investigator then design the harmonic filter at Hercules Controls Panel Pvt. Ltd. Udaipur, Rajasthan (India), after installation of harmonic filter at Arihant Marble Industry and measurement were done again and found that 5th harmonic content was below IEEE limits. Investigator also calculate the kVA saving.
Utilización de lodos de corte y pulido del mármol en la recuperación de escombreras de mármol Making use of mud from marble cutting and polishing to recuperate rubble marble
J. A. Sánchez,I. García,F. del Moral,S. de Haro
Revista de Ciências Agrárias , 2010,
Abstract: En la regeneración de las escombreras de las explotaciones de Mármol de Macael (Almería), las elevadas pendientes (> 60%) y el marcado contraste textural entre los fragmentos de estériles (Φ medio ≈ 2 cm) y el suelo aportado en superficie (Φ medio ≈ 30 μm), condiciona que los gruesos poros de los estériles carezcan de capacidad de succión, lo que hace que se comporten como impermeables, y en el suelo adiciona-do se origina un flujo en embudo que, cuan-do aflora en superficie, erosiona y rompe la manta orgánica de protección. Para evitar dicha erosión, los gruesos poros de la escombrera se rellenaron con lodo de corte y pulido del mármol. El nuevo sistema incrementó la succión y el agua retenida por unidad de superficie, y disminuyó el déficit hídrico de la vegetación implantada y el flu-jo en embudo y, por tanto, los procesos de erosión. In the regeneration of the rubble marble quarrying in the region of Macael (Almería), the steep slopes (>60%) and marked textural contrast between the pores of the sterile fragments (average Φ≈ 2 cm) and those of the superficial soil (average Φ ≈ 30 μm), determine that the extremely large pores of the sterile materials lack suc-tion capacity and are therefore impermeable. As a result, in the superficial soil funnel flow occurs, causing erosion when it comes to the surface, and breaking the organic protection. To avoid this phenomenon, the large pores of the slag heap are filled with the sludge arising from marble cutting and polishing. This new system increased suction capacity and water retention by surface unit, and di-minished the hydric deficit of the vegetation and the funnel flow effect, thus reducing the erosion process.
Freezing of a Liquid Marble  [PDF]
Ali Hashmi,Adam Strauss,Jie Xu
Physics , 2012, DOI: 10.1021/la301854f
Abstract: In this study, we present for the first time the observations of a freezing liquid marble. In the experiment, liquid marbles are gently placed on the cold side of a Thermo-Electric Cooler (TEC) and the morphological changes are recorded and characterized thereafter. These liquid marbles are noticed to undergo a shape transition from a spherical to a flying-saucer shaped morphology. The freezing dynamics of liquid marbles is observed to be very different from that of a freezing water droplet on a superhydrophobic surface. For example, the pointy tip appearing on a frozen water drop could not be observed for a frozen liquid marble. In the end, we highlight a possible explanation for the observed morphology.
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