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Literatura académica sobre el tema "Natural limestone"

Autor: Grafiati

Publicado: 1 de junio de 2024

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Artículos de revistas sobre el tema "Natural limestone"

Pivko, Daniel. "Litavský vápenec zo St. Margarethenu a Fertőrákosu a jeho využitie na Slovensku ako dekoračný kameň". Geologické práce Správy 138 (24 de febrero de 2023): 95–118. http://dx.doi.org/10.56623/gps.138.4.

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In Western Slovakia, especially in the Bratislava region and Trnava region, Leitha limestone of the Badenian (Langhian – early Serravalian) age from St. Margarethen in Austria was widely used for architectural articles and sculptures (200 realizations), alternatively a similar limestone from Fertőrákos in Hungary. 380 tombstones were identified only in Bratislava cemeteries. From the second half of the 17th century to the first half of the 20th century, the limestones were one of the most used in Slovakia due to their light dressing and relatively homogeneous appearance. The strongly porous coarse-grained to medium-grained the Leitha limestone has the appearance of sandstone and is composed of a predominance of red algae nodules over foraminifers, sea urchin, moss and shell fragments. The rhodoliths, pectenoids and oysters are scattered in the Leitha limestones up to a few cm size, which distinguish the limestone type from other the Leitha limestones and similar Sarmatian limestones. The limestone is dominated by rhodolithes in the St. Margarethen quarry and by bivalves and macroscopic quartz in Fertőrákos quarry. Porous limestones are exposed to weathering outdoors, leading to mass loss, flaking, sulphate efflorescence, black crusts from microscopic organisms and the colonization by lichens and mosses. The peak of limestone use for public buildings and sculptures was the years 1745 to 1780 (reign of Maria Theresa), and about 1880 to 1915, when there was relative prosperity and machine production began. The tombstones made of the Leitha limestones shifts to a peak between 1905 and 1925. In the 20th century, the Leitha limestones gave way to a competition from Czech decorative stones.

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Hagen, Arnulf P., William D. Lee y Tisha M. Jones. "Asphalt-Aggregate Interactions Characterized by Zeta Potential and Retained Strength Measurements for Natural and Organosilane-Treated Aggregates". Transportation Research Record: Journal of the Transportation Research Board 1535, n.º 1 (enero de 1996): 111–16. http://dx.doi.org/10.1177/0361198196153500114.

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Zeta potentials in water have been measured for a poorly performing, easily stripped hard limestone, a well-performing hard limestone, a sandstone, a rhyolite, soda lime glass beads, and for eight AC-20 asphalt binders. Four of the binders selected to represent a range of zeta potentials were combined with the sandstone, the limestones, and the glass beads according to Oklahoma Department of Transportation mix formulas and tested for retained strength. The good hard limestone was the best overall performer with retained strengths of 96 to 100 percent, the poor hard limestone was acceptable, overall the sandstone was unsatisfactory; and the glass beads did not survive the retained strength preconditioning procedure. The aggregates were then treated with organosilane derivatives to chemically modify their surfaces and to change the aggregate zeta potential. For example, the zeta potential of the poor hard limestone was made to be closer to that of the good hard limestone. The modified aggregates were then used in the same mix and the retained strengths measured. The good hard limestone mix exhibited no change in retained strength; however, the poor hard limestone, the sandstone, and the glass bead mixes gave excellent retained strengths.

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Kramar, Sabina, Nina Žbona, Mojca Bedjanič, Ana Mladenović y Boštjan Rožič. "Drenov Grič black limestone: a heritage stone from Slovenia". Geological Society, London, Special Publications 486, n.º 1 (16 de julio de 2019): 149–62. http://dx.doi.org/10.1144/sp486-2017-188.

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AbstractDrenov Grič black limestone is considered to be one of the most beautiful Slovenian natural stones due to its black colour interwoven with white veins. Over the centuries, it has been extracted from two major quarries located west of Ljubljana. One of these quarries has been declared a valuable natural feature of national importance and is protected as a natural monument. This well-stratified, Triassic (Carnian) micritic limestone occurs in 10–80 cm thick beds with thin marl interlayers. The limestone occasionally contains abundant fossil bivalves, gastropods and ostracods. It is relatively rich in carbonaceous and bituminous organic matter, which is responsible for the black colour of the stone. The stone has been widely used in Slovenian monuments. Many indoor and outdoor architectural elements have been constructed using this limestone, particularly during the Baroque period, which was known for its extensive use of black limestones in other European countries as well. The most significant use of this limestone has been recorded in sculpted portals and altars. Some important buildings, which were decorated utilizing this stone, have been declared cultural monuments of local or national importance. Use of this limestone was also documented in other European countries (Italy, Austria, Serbia) and worldwide (USA). When exposed to climatic influences, chromatic and salt weathering are recognized as the main deterioration phenomena for this limestone when used in monuments.

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Mohammed, Syakirah Afiza, Abdul Ghapar Ahmad, Ragunathan Santiagoo, Vikneswaran Vijean, Wan Amiza Amneera Wan Ahmad, Razi Ahmad y Lim Shi Kai. "Optimum Binder Content of Asphaltic Concrete (ACW14) Mixture Incorporating Limestone". IOP Conference Series: Earth and Environmental Science 1216, n.º 1 (1 de julio de 2023): 012020. http://dx.doi.org/10.1088/1755-1315/1216/1/012020.

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Abstract Due to the high demand for natural aggregates in pavement construction, researchers have been looking for alternative materials to replace natural aggregate. In this research, the optimum binder content of asphalt mixture incorporate limestones was investigated. The optimum binder content of asphalt mixture was tested according to Marshall method. About 20 % of limestone was used as aggregate replacement in asphaltic concrete mixture. To determine the stability, volumetric properties, and bitumen binder content, three percentage of asphalt binder content, namely 4.0%, 5.0% and 6.0% was prepared. From analysis, it indicated that stability and volumetric properties of asphalt mixture incorporate limestone meet the requirement set by JKR. From the result obtained, the optimum binder content of the control sample is 5.0% and optimum binder content of limestone mixture is 5.2%. The slightly different in optimum binder content value indicate that the optimum binder content of limestone mixture was comparable with control mixture.

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Knezevic, Milan y Olivera Kosanin. "Genesis and characteristics of the soil in A-R stage in forest ecosystems of NP 'Tara'". Bulletin of the Faculty of Forestry, n.º 99 (2009): 75–89. http://dx.doi.org/10.2298/gsf0999075k.

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Different types of soil in A-R stage formed on limestone and serpentinite in forest ecosystems in NP 'Tara' were researched. Based on the specific effect of limestone on the soil genesis and evolution, two types of calcareous limestone bedrocks were distinguished: dense limestones, and soft, marly limestones. Three subtypes of black earth were studied on dense limestones. They are: organogenic, organo-mineral and brownised soils. One soil type was researched on soft, marly limestones: rendzina, the leached variety. One soil type was researched on serpentinites, within the A-R stage: humus-siliceous soil (ranker), subtype eutric ranker. This paper also presents the evaluation of ecological and productive characteristics of the study soils. If the soil is observed separately, regardless of the tree species growing on it, the soils in A-R stage in NP 'Tara' cannot be evaluated as highly productive. However, in all plant communities on the soils in A-R stage on limestone, the values of average volume, current volume increment, and basal area were high. The unfavourable physical characteristics of the soil in the area of NP 'Tara' are compensated by the effect of humid climate. On the study eutric humus siliceous soils in the area of NP 'Tara', in the natural and artificially established stands of Scots pine and Austrian pine, the ecological and productive value is conditioned by numerous factors and it is mainly limited by unfavourable physical characteristics. Regardless of the unfavourable ecological and productive characteristics of the soil, the natural and artificially established stands of Scots pine and Austrian pine are in the coeno-ecological optimum.

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Wang, Yige, Tao He, Guocheng Rong, Putao Song, Jingliang Xia y Faguang Leng. "Study on Crack Resistance of C35 Limestone Powder Concrete". Journal of Physics: Conference Series 2468, n.º 1 (1 de abril de 2023): 012025. http://dx.doi.org/10.1088/1742-6596/2468/1/012025.

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Abstract C35 pier concrete was prepared with natural limestone powder and fly ash, and the effect of the proportion of limestone powder and fly ash on hydration heat of composite cementitious material system was studied At the same time, the effects of different proportions of natural limestone powder and fly ash on adiabatic temperature rise, early shrinkage, drying shrinkage and early cracking of concrete were studied. The results show that the hydration heat of composite cementitious material system can be reduced by adding natural limestone powder and fly ash, the early shrinkage and dry shrinkage of concrete can be reduced, and the cracking of concrete can be reduced. On the contrary, when natural limestone powder and fly ash replace cement by 20%, 10% mass ratio, C35 concrete has the best indexes and better crack resistance.

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Lai, LanXin, Toshio Imai, Motohiro Umezu, Mamoru Ishii y Hironao Ogura. "Possibility of Calcium Oxide from Natural Limestone Including Impurities for Chemical Heat Pump". Energies 13, n.º 4 (12 de febrero de 2020): 803. http://dx.doi.org/10.3390/en13040803.

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Improving energy recycle is an important way to save energy resources and preserve the global environment. Chemical heat pump (CHP) is a technology for saving energy, which utilizes chemical reactions to store thermal energy such as waste heat and solar heat, then release it to provide heat for heating/cooling/refrigeration. For a practical CHP, it is necessary to find cheaper and more stable supply materials. In order to evaluate the possibility of calcium oxide from natural Ofunato natural limestone including impurities, we compare Ofunato limestone with Kawara natural limestone and Garou natural limestone from Japan. These calcium oxides worked as a reactant for CaO/H2O/Ca(OH)2 CHP by repeated hydration/dehydration reaction cycle experiments in a thermogravimetric analyzer. As a result, Ofunato CaO exhibits a high hydration reaction rate after decarbonization at 1223 K for 5 h. The reactivity increased by the repeated hydration reaction although the first hydration rate was low. Furthermore, the sintering of impurities in Ofunato limestone occur easier than that in Kawara limestone with lower impurities. The impurities adhered to the surface of the CaO particle to make specific surface area of CaO particle smaller, which could inhibit hydration reaction of CaO particle. Even if Ofunato limestone contains some impurities, it can be utilized as a raw material for chemical heat pumps.

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Hao, Xiu Hong, Ai Qin Zhang y Zhi Guo Liu. "Influence of Fine Aggregate on the Performance of Asphalt Concrete". Advanced Materials Research 598 (noviembre de 2012): 655–58. http://dx.doi.org/10.4028/www.scientific.net/amr.598.655.

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The performance of asphalt concrete mixed with 3 types of fine aggregate respectively (i.e. natural sand, limestone, basalt) are compared. The results of Marshall test and rutting test show that the high temperature performance of asphalt mixture mixed with basalt is the best, that of asphalt mixture mixed with natural sand is the worst, and that of asphalt mixture mixed with limestone is between the above two. The result of immersion Marshall test show that the water stability of asphalt mixture mixed with basalt and that of asphalt mixture mixed with limestone are similar, but better than that of asphalt mixture mixed with natural sand. Therefore, it indicates that the machine-made aggregate (of basalt or limestone) have better pavement performance and environment benefit than the natural sand.

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Kostohryz, K. P., V. A. Zhaivoronok, Yu I. Khvastukhin y S. M. Roman. "PRODUCTION OF LIME WITH HIGH REACTIVITY IN A FLUIDIZED BED APPARATUS OF AN INERT MATERIAL". Energy Technologies & Resource Saving, n.º 1 (20 de diciembre de 2018): 31–37. http://dx.doi.org/10.33070/etars.1.2018.04.

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In dry desulfurization, for example, of gaseous combustion products of thermal power plants and incineration plants, calcium oxide CaO, as a product of firing of natural carbonate rocks, mainly limestones (CaCO3), is widely used. Firing technology, depending on the limestone heat treatment regimes, form a product with certain physicochemical properties: porosity, specific surface, shrinkage value, chemical activity. The influence of heat treatment conditions on the properties of the product obtained is studied. The possibility of fast low temperature heat treatment of finely dispersed limestone in a fluidized bed of an inert material to produce CaO of the required quality is shown. Research facility, technique for carrying out experiments and processing experimental data are described. As a result of the research, the degree of calcination of 80 % of fine limestone in a device with fluidized bed of inert material was achieved and the residence time of the particles in the inert layer was determined. Bibl. 10, Fig. 2, Tab. 1.

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La Verde, Giuseppe, Adelaide Raulo, Vittoria D’Avino, Giovanni Paternoster, Vincenzo Roca, Marco La Commara y Mariagabriella Pugliese. "Pietra Leccese and Other Natural Stones in Puglia Region: A New Category of Building Materials for Radiation Protection?" International Journal of Environmental Research and Public Health 18, n.º 21 (26 de octubre de 2021): 11213. http://dx.doi.org/10.3390/ijerph182111213.

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In this paper, an in-depth and systematic study of the radiological characterization of three types of Puglia region natural limestones (Pietra Leccese, Pietra Mazzara and Carparo) was carried out. The investigation was performed by XRF spectroscopy for a chemical analysis, and gamma spectroscopy of the specific activity concentration of natural radionuclides 226Ra, 232Th, and 40K. Although the limestone does not fall within the category included by Italian Legislative Decree 101/2020, the gamma index was calculated using the results of the gamma spectroscopy measurements. For Pietra Mazzara and Carparo stones, the gamma index was found to be less than the reference value; conversely Pietra Leccese was found to be higher. To obtain a more complete evaluation of the external exposure, radium equivalent activity and external radiation hazard were calculated for all analyzed stones. The results suggest the need to broadly consider the radiological risk for these stones, and for limestone more generally, when used as a building material.

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Más fuentes

Tesis sobre el tema "Natural limestone"

Cuoghi, Giulia. "Theoretical and experimental behavior of prestressed natural stone beams". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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L’obiettivo di molte ricerche attuali riguarda nuove soluzioni costruttive per l'edilizia futura. In particolare, la ricerca si focalizza sullo sviluppo tecnologico di materiali naturali preesistenti con lo scopo di realizzare strutture innovative, sicure ed ecosostenibili. La presente tesi si propone di studiare la possibilità di utilizzare materiali naturali, come la pietra, per la costruzione di strutture portanti. Il calcare Cabouca è stato scelto per la realizzazione di una trave a blocchi, resa resistente e compatta attraverso la tecnica della precompressione. Le prove meccaniche sui campioni di pietra e successivamente, la costruzione e la prova a flessione della trave sono stati effettuati presso il Laboratório de Estruturas Pesadas, Faculdade de Ciências e Tecnologia, presso l'Università di Lisbona. I risultati soddisfacenti hanno evidenziato un sostanzioso incremento della capacità flessionale della trave precompressa rispetto a quella non armata, potendo quindi dimostrare che la precompressione è efficace nella pietra naturale come nel calcestruzzo. Il presente lavoro si propone come un punto di partenza valido per l'evoluzione di strutture portanti in pietra precompressa eleganti, sicure e conformi ai principi del Green building.

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Huck, Scott W. "Controls on Natural Fractures in the Upper Lexington Limestone and Point Pleasant Formation: Central-Ohio". Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1372061876.

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Dias, Luís Carlos Rosmaninho. "STONECOLOR: color of commercial marbles and limestone - causes and changes". Doctoral thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/26969.

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Historically centred in the European and Asiatic countries, the ornamental stone production is currently one of the most important sectors for the Portuguese economy. In fact, Portugal is today one of the leaders in the production of natural stone worldwide, namely in the limestone and marble exploitation. The production increment over the last several years is related with the high quality of the carbonated stones existing in the Portuguese territory together with the Portuguese experience in stone manufacture, acquired since ancient times. In this context, colour is one of the most important visible aspects of natural stone, for the construction/restoration of new buildings and/or for Cultural Heritage preservation. Therefore, colour and discolouration of stone is currently an important research topic for the scientific community, where the association stone-colour-microorganism is still unexploited. This PhD aimed to determine the causes that affect the colour of Portuguese marbles and limestones. Therefore, several lithotypes of natural stone with high relevance for the Portuguese natural stone industry and for Cultural Heritage assets were selected and studied. In order to characterise discolouration phenomena, the processes of natural stones’ weathering were assessed, and the microbiota thriving on the stones was determined. The microorganisms’ contribution for the stone discolouration phenomena was evaluated through the execution of artificial ageing assays, under controlled environment. The results obtained allowed to identify the main chromophore components of the Portuguese carbonated stones studied. It was also finding and determined that the colour change occurred on the blue limestone is achieved through the natural weathering of pyrite, and this mechanism is accelerated when microorganisms are present. Regarding the cultural heritage assets study, it was finding that colour alterations of the stone are caused mainly by chemical and biogenic actions; Resumo: Tradicionalmente centrada nos países Europeus e Asiáticos, a produção de Pedra Ornamental tem-se tornado num dos mais importantes setores da economia Portuguesa. Portugal é hoje, de facto, um dos líderes ao nível mundial na produção de Pedra Natural, nomeadamente de calcários e mármores. O aumento na produção ao longo destes últimos anos está relacionada não só com a elevada qualidade das rochas carbonatadas que aqui se encontram, mas também com a experiência portuguesa no manuseamento da Pedra. A cor, neste contexto, é um dos aspetos visíveis mais importantes na Pedra Natural, tanto na construção/restauro de novos edifícios como na preservação de Património Cultural. Deste modo, a cor e a descoloração da Pedra tem-se tornado num dos importantes tópicos de investigação para a comunidade científica, onde uma das lacunas é a falta de associação pedra-cor-microorganismo. Com este projeto pretendeu-se contribuir para a compreensão das causas de cor em rochas carbonatadas portuguesas, como o calcário e o mármore, onde foram selecionados e estudados diversos litótipos de Pedra Natural com elevada relevância para a indústria da Pedra portuguesa e para o património cultural construído. Para caracterizar fenómenos de descoloração, foram estudados os processos de meteorização de rochas e foi determinado o estado de biocolonisação do material. O contributo dos microorganismos para o fenómeno de descoloração de Pedra foi avaliado através da execução de ensaios de envelhecimento artificial, sob ambiente controlado. Os resultados obtidos permitiram identificar os principais elementos cromóforos das rochas carbonatadas portuguesas estudadas. Foi ainda determinado que a alteração da cor no calcário azul é causada pela pela meteorização natural da pirite, e que este mecanismo é acelerado na presença de agentes microbianos. Relativamente ao estudo dos bens patrimoniais, foi determinado que as alterações cromáticas aqui presentes são sobretudo de origem química e biogénica.

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Bell, James Robert. "Habitat use, community structure and biogeography of spiders (Araneae) in semi-natural and disturbed limestone grassland". Thesis, Manchester Metropolitan University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297980.

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Hornbeck, Joseph R. "A Comparison of the Ichthyofaunal Trophic Ecology at Selected Limestone Artificial Reef Sites and Adjacent Natural Reef Sites". NSUWorks, 2017. http://nsuworks.nova.edu/occ_stuetd/438.

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Artificial reefs may enhance the biological production of reef-associated flora and fauna, but their trophic structure relative to that of natural reefs remains understudied. We assessed trophic dynamics by comparing δ13C and δ15N in 43 fish species from artificial and natural reef tracts of Broward County, Florida. We tested the effect of sampling location (artificial, first, and second reef), general feeding strategy (herbivore, omnivore, planktivore, invertivore, and carnivore), phylogeny, and standard length. For all samples, δ13C and δ15N ranged from -19.5 to -13.1‰ and 6.7 to 13.3‰, respectively. Lower trophic level feeding behavior resulted in more depleted δ13C and δ15N and higher trophic level feeding behavior resulted in more enriched δ13C and δ15N. We detected significant effects of both general feeding strategy and phylogeny. We also detected significant differences in δ13C and δ15N profiles between artificial and natural reefs; however, these differences were not great enough to suggest changes in the feeding strategy or trophic dynamics of individual fish taxa.

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Prestes, Nelson Eduardo. "Calagem, adubação e introdução de espécies em pastagem natural do Planalto Catarinense". Universidade do Estado de Santa Catarina, 2015. http://tede.udesc.br/handle/handle/533.

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The aim of this work was to evalute herbage production of a natural grasslands submitted to limestone and phosphorus levels, applied superficially, without introducing species (Chapter 1) and overseeded with temperate climate species (Chapter 2). The experiment was conducted from January 2010 to December 2013. In Chapter 1 liming was applied in quantities of 0.0; 7.2 and 14.4 t ha-1; and phosphorus as triple superphosfate, at levels of 0; 35; 70 and 140 kg ha-1 P2O5. The experimental design was a randomized block design in a split plot arrangement with 3 repetitions, with limestone levels distributed in the main plots and P in the subplots. There was no significant interaction between the limestone and phosphate treatments in both studies. The elevation of limestone increased forage production only from the 3rd year, a linear response, with maximum value of 1182.3 kg DM ha-1, with 14.4 t ha-1 lime, and quadratic in 4th year, with 2316.1 kg DM ha-1, with 7.2 t ha-1 of lime. There was statistical difference at P applications from the 2nd year, with the greatest production obtained in the 4th year, with 140 kg P2O5 ha-1 producing 2232.8 kg DM ha-1. Limestone promoted changes up to 10cm of soli layer. Of 0-5cm, 14.4 t ha-1, increased pH from 4.77 to 6.45, Al decreased from 2.51 to 0.0 cmolc kg-1 and base saturation (V%) increased from 31.34 to 84.17%. With the P levels changes occured mainly up to 5cm. Chapter 2: limestone in 3.6; 7.2; 11.0 and 14.4 t ha-1; and P in doses of 35; 70; 105 and 140 kg P2O5 ha-1, and overseeded species of cold season the maximum production was of 3932.2 kg DM ha-1 in the 2nd year with a dose of 11 t of limestone. The red clover responded better to this limestone application on levels 7-11 t ha-1. Phosphorus significantly increased herbage production in four years. Forage production reached the ceiling in the 2nd year, 4419.4 kg DM ha-1 with 140 kg P2O5 ha-1. The red clover was established and persisted better than the other species with increasing levels of limestone and limestone and P. The P, mainly concentrated their effects up to 5cm of soil layer. A 14.4 tonnes of applied lime the pH reached 6.04, Al 0.03 kg cmolc V-1 and 74.56% at%. At the same soil layer 140 kg ha-1 P2O5, P increased to 12.08 mg kg-1. Lime application of 25% (7.2 t ha-1) of the recommended dose, associated with phosphorus dose of 50% of the recommendation (70 kg P2O5 ha-1), potentiate the production of forage on native pasture with a predominance of Schizachirium tenerum. The application of 1/8 dose (3.6 t ha-1) of the lime requirement allows the establishment and persistence of legumes introduced in native grass; 1/8 (3.6 t ha-1) of the official recommendation of the dose associated with limestone phosphorus increasing doses increase linearly forage production. This enhancement is due primarily to the effect of P in the production increase of introduced legumes
Avaliou-se a produção de um campo nativo submetido a níveis de calcário e fósforo, aplicados superficialmente, sem a introdução de espécies (Capítulo 1) e com sobressemeadura de espécies de estação fria (Capítulo 2) de janeiro/10 a dezembro/13. No Capítulo 1 a calagem foi de 0,0; 7,2 e 14,4 t ha-1; e aplicação de SFT, nosníveis de 0; 35; 70 e 140 kg de P2O5 ha-1. O delineamento experimental dos ensaios foi de blocos ao acaso com parcelas subdivididas, com 3 repetições, com níveis de calcário distribuídos na parcela principal e as doses de P nas sub-parcelas. Não houve interação significativa entre os tratamentos de calcário e fósforo nos dois estudos. A elevação das doses de calcário aumentou a produção de forragem somente a partir do 3º ano, sendo a resposta linear, com valor máximo de 1.182,3 kg MS ha-1, com 14,4 t de calcário ha-1, e quadráticano 4º ano, com 2.316,1 kg MS ha-1, com 7,2 t de calcário ha-1. Houve diferença estatísticaàs aplicações de P a partir do 2º ano, sendo a maior produção obtida no 4º ano, com 140 kg P2O5 ha-1 produzindo 2.232,8 kg MS ha-1. O calcário promoveu maiores alterações até 10cm. De 0-5cm, 14,4 t ha-1, elevou o pH de 4,77 para 6,45, o Al reduziu de 2,51 para 0,0 cmolc kg-1 e a saturação por bases (V%) aumentou de 31,34 para 84,17%. Com as doses de P,acréscimos importantes limitaram-se principalmente até 5cm. Capítulo 2: com calcário em 3,6; 7,2; 11,0 e 14,4 t ha-1; e P nas doses de 35; 70; 105 e 140 kg de P2O5 ha-1, e com sobressemeadura de espécies de estação fria, o calcário, com 11 t ha-1, teve com produção máxima 3.932,2 kg MS ha-1, no 2º ano. O trevo-vermelho respondeu melhor a este corretivo, nos níveis de 7 a 11 t ha-1. O P foi significativo à produção de forragem nos quatro anos. A forragem atingiu o teto produtivo no 2º ano, 4.419,4 kg MS ha-1 com 140 kg P2O5 ha-1. O trevo-vermelho se estabeleceu e persistiu melhor que as demais espécies com os níveis crescentes de calcário e P. O calcário e P, concentraram seus efeitos principalmente até 5cm. Com 14,4 t de calcário o pH chegou a 6,04, o Al a 0,03 cmolc kg-1 e a V% a 74,56%. Nesta camada, 140 kg P2O5 ha-1, elevou o P para 12,08 mg kg-1. Aplicação de calcário de 25% (7,2 t ha-1) da dose recomendada, associada com dose de fósforo de 50% da recomendação (70 kg P2O5 ha-1), potencializam a produção de forragem em campo natural com predomínio de Schizachirium tenerum.A aplicação de dose de 1/8 (3,6 t ha-1) da recomendação de calcário permite o estabelecimento e a persistência de leguminosas introduzidas em campo nativo; 1/8 (3,6 t ha-1) da dose da recomendação oficial de calcário associada com doses crescentes de fósforo aumentam linearmente a produção de forragem. Essa potencialização se deve, principalmente, ao efeito do P no incremento produtivo das leguminosas introduzidas

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Grill, Nicolette Deannah. "ECONOMIC GEOLOGY OF THE SAN BERNARDINO MOUNTAINS, CALIFORNIA". CSUSB ScholarWorks, 2014. https://scholarworks.lib.csusb.edu/etd/102.

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The San Bernardino Mountains are well known for their rich mining history, especially, gold in the mid-1800s and the current mining of one of the world’s largest deposits of high purity limestone. The purpose of this study was to compile new, current, and historical data of the major economic resources that are present and mining that has gone on in the San Bernardino Mountains. It is estimated that historical mining of the Holcomb Valley recovered $457,660,000 of gold or about 350,000 troy ounces based on samples collected for this study and 2013 gold price. The current major geologic resource is the limestone deposits on the north slope of the San Bernardino Mountains. Presently, there are three operators: Omya, Specialty Minerals, and Mitsubishi Cement. The San Bernardino Mountains are well known for skarn gold deposits. New work indicates that the placer gold from Holcomb Valley is often of very high purity. Placer gold samples were analyzed using the scanning electron microscope and energy dispersive x-ray spectra to determine the purity of the gold. Rim and core analysis of the placer gold was used to determine if the gold was transported from its source and to give an estimate of transportation distance. Results show some of the placer gold of Holcomb Valley has been rounded and flattened by weathering and transportation with increased gold purity in the rims while other gold grains still sustain their octahedral crystalline structure. Rims range in gold purity from 84.26% to 100%, with core gold purity ranging from 79.51% to 99.79%. Gold samples were weighed, photographed, measured, and classified by shape, angularity and texture, to assess the effects of transportation. Gold weights where used to calculate an economic value of gold. Geographic Information System “GIS” was used to visually display geology, historical and current mine locations, locations of samples used in this study, and to help calculate the volume of the Holcomb Valley TsE rock unit, which is where the placer gold is deposited. Sediment sample 15 from TsE had the lowest gold value of .002 ounces per cubic yard. This value is inferred to represent the amount of gold remaining after mining. Based on this assumption and the estimated volume of TsE at 50,027,000 cubic yards, the estimated total weight of gold remaining in the deposit is about 100,000 troy ounces, with a dollar value of about $130,760,000, using gold values for 2013. Sample 17 had the highest gold value, with .014 ounces per cubic yard. This is inferred to represent the concentration of placer gold deposits within parts of Holcomb Valley that have never been mined. This yields a total weight of the deposit of roughly 700,000 troy ounces, with an estimated value of $915,320,000 using gold prices for 2013. The gold values were calculated using November 7, 2013 gold spot price of $1,307.60.

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Akhoondan, Mersedeh. "Corrosion Evaluation and Durability Estimation of Aluminized Steel Drainage Pipes". Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4273.

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Aluminized steel pipes are expected to have a long service life, e.g. 75 years. Spiral ribbed aluminized pipes (SRAP) have been widely specified and used by the Florida Department of Transportation (FDOT) for drainage of runoff water. Confidence in the long term durability of SRAP has been challenged by recent unexpected early corrosion failures in various Florida locations. SRAP premature corrosion incidents have occurred in two modalities. Mode A has taken place in near-neutral soil environments and has often been associated with either gross manufacturing defects (i.e. helical cuts) or corrosion concentration at or near the ribs. Mode B took place in pipes in contact with limestone backfill and corrosion damage was in the form of perforations, not preferentially located at the ribs, and not necessarily associated with other deficiencies. These failures motivated this research. The objectives of this work are to establish to what extent the Mode A corrosion incidents can be ascribed to manufacturing defects, that can be rectified by appropriate quality control, as opposed to an intrinsic vulnerability to corrosion of regularly produced SRAP due to ordinary forming strains and to determine the mechanism responsible for Mode B corrosion including the role that limestone backfill played in that deterioration. To achieve those objectives, laboratory experiments were conducted to replicate the conditions for Mode A and Mode B. Overall, the findings of this and previous work suggest that much of the corrosion damage observed in the Mode A incidents were promoted more by manufacturing deficiencies and less by any possible inherent susceptibility of corrosion at the ribs of SRAP that was produced following appropriate quality control. Experiments to explore the causes of Mode B corrosion showed that high pH values, sufficient to cause dissolution of the passive film on aluminum, can develop under exposure of limestone to flowing natural water. The findings substantiate, for the first time, an important vulnerability of aluminized steel in limestone soils and provide an explanation for the rapid onset deterioration observed at the field under Mode B. The findings also provide strong evidence in support of service guidelines to disallow the use of limestone bedding for aluminized steel pipe, including SRAP.

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Araújo, Bárbara Mafra de. "Influência de calagem e adubação fosfatada no crescimento inicial de Eucalyptus benthamii e Eucalyptus dunnii no Planalto Norte Catarinense". Universidade do Estado de Santa Catarina, 2014. http://tede.udesc.br/handle/handle/1960.

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Made available in DSpace on 2016-12-12T20:12:33Z (GMT). No. of bitstreams: 1 PGEF14MA047.pdf: 93789 bytes, checksum: 5a7cdb0b1f0327506fa6f01fd57c89cb (MD5) Previous issue date: 2014-05-30
Among the economically important species of eucalyptus for southern Brazil, the most suitable are Eucalyptus benthamii and Eucalyptus dunnii, due to its tolerance to low temperatures. However, there is little information about the nutritional requirements and studies showing aspects involving nutrition versus the development of these species. Coupled with the high demand for use of fertilizers and, in order to obtain substantial productivity gains for most of eucalyptus forests located in the South of Brazil soils, it is necessary to determine suitable doses depending of the soil type and the genetic material. This study aimed to evaluate the initial response of Eucalyptus benthamii and Eucalyptus dunnii to different doses of phosphorus fertilization and liming in the study region. There were specific objectives, as: to evaluate the initial growth of the plants of Eucalyptus benthamii and Eucalyptus dunnii, based on the dendrometric variables height and crown diameter; evaluate and interpret the effect of different doses of rock phosphate (RF), mixed mineral fertilizer (MF) and limestone in the initial growth of these species. Thus, it was conducted a field experiment, located in the city of Rio Negrinho - SC, in the period November 2012 to November 2013. The experimental design was a randomized block design with three replications, conducted in three 2 x 4 factorial schemes. Considering the A factor constituted by two species (Eucalyptus benthamii and Eucalyptus dunnii) and the B factor: a) four levels of RF (0, 400, 600 and 800 kg ha-1 in the form of reactive Gafsa RF); b) four doses of MF (0, 150, 200 and 250 kg ha-1 of NPK 6-30-6 formulation); c) four liming levels (0, 3.5, 6 and 10 t ha-1 in the form of dolomitic lime). The plots had 270 m² of area, with 45 plants in each. Total height measures and diameter of the tree canopy to 330 days after planting were performed. The results showed that the phosphate fertilizer (RF and MFM) and liming increased growth in height and crown diameter of Eucalyptus benthamii and Eucalyptus dunnii plants during the first 11 months of grow. The growth response of Eucalyptus benthamii was higher than Eucalyptus dunnii, in all evaluated factorial schemes. The lowest dose of RF was effective for the growth of Eucalyptus benthamii and obtained slightly higher growth for Eucalyptus dunnii when associated with dose of 6 t ha-1 of lime and, mainly, to 10 t ha-1 of lime. The higher dose of MF was effective on the Eucalyptus benthamii growth and slightly higher for Eucalyptus dunnii, but only when combined with a dose of 10 t ha-1 of lime. The lower dose of lime had satisfactory growth for Eucalyptus dunnii, while the higher dose of lime was effective in the growth of Eucalyptus benthamii, when associated with a dose of 400 kg ha-1 RF, a condition that was found slightly higher than results of the studied dendrometric parameters
Entre as espécies de eucalipto economicamente importantes para a Região Sul do Brasil, as mais indicadas são Eucalyptus benthamii e Eucalyptus dunnii, devido às suas tolerâncias às baixas temperaturas. No entanto, são escassas as informações sobre as exigências nutricionais e estudos que apresentem aspectos que envolvam a nutrição versus o desenvolvimento dessas espécies. Aliado a elevada demanda por utilização de fertilizantes e corretivos para que se obtenham ganhos substanciais de produtividade para grande maioria das florestas de eucaliptos situados nos solos do Sul do Brasil, é necessário determinar doses adequadas em função do tipo de solo e do material genético. O trabalho objetivou avaliar a resposta inicial de Eucalyptus benthamii e Eucalyptus dunnii a diferentes doses de adubação fosfatada e calagem na região do Planalto Norte Catarinense. Tendo como objetivos específicos: avaliar o crescimento inicial das plantas de Eucalyptus benthamii e Eucalyptus dunnii, a partir das variáveis dendrométricas altura e diâmetro de copa; avaliar e interpretar o efeito de diferentes doses de fosfato natural (FN), fertilizante mineral misto (FM) e calcário no crescimento inicial dessas espécies. Nesse sentido, foi conduzido experimento a campo, localizado no Município de Rio Negrinho SC, no período de novembro de 2012 a novembro de 2013. O delineamento experimental utilizado foi o de blocos ao acaso com três repetições, conduzido em três esquemas fatoriais 2 x 4. Sendo fator A constituído por duas espécies (Eucalyptus benthamii e Eucalyptus dunnii) e o fator B por: a) quatro doses de FN (0, 400, 600 e 800 kg ha-1 na forma de FN reativo de Gafsa); b) quatro doses de FM (0, 150, 200 e 250 kg ha-1 da formulação 6-30-6 de NPK); e c) quatro doses de calcário (0, 3,5, 6 e 10 t ha-1 na forma de calcário dolomítico). As parcelas possuíam 270 m² de área útil, apresentando 45 plantas em cada. Foram realizadas medidas de altura total e diâmetro de copa das árvores aos 330 dias após plantio. Os resultados mostraram que a adubação fosfatada (FN e FM) e a calagem aumentaram o crescimento em altura e diâmetro de copa das plantas de Eucalyptus benthamii e Eucalyptus dunnii durante os primeiros 11 meses de cultivo. A resposta de crescimento do Eucalyptus benthamii foi superior em relação ao Eucalyptus dunnii, em todos os esquemas fatorais avaliados. A menor dose de FN foi efetiva no crescimento de Eucalyptus benthamii e obteve crescimento ligeiramente superior para Eucalyptus dunnii, quando associada à dose de 6 t ha-1 de calcário e, principalmente, à 10 t ha-1 de calcário. A maior dose de FM foi efetiva no crescimento de Eucalyptus benthamii e ligeiramente superior para Eucalyptus dunnii, porém, somente quando associada à dose de 10 t ha-1 de calcário. A menor dose de calcário obteve crescimento satisfatório para Eucalyptus dunnii, enquanto a maior dose de calcário foi efetiva no crescimento de Eucalyptus benthamii, quando associada à dose de 400 kg ha-1 de FN, condição que foi constatada resultados ligeiramente superiores dos parâmetros dendrométricos estudados

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Soyluoglu, Serdar. "Effects Of Separate And Intergrinding On Some Properties Of Portland Composite Cements". Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611365/index.pdf.

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In the production of cement, to increase the cement/clinker ratio and decrease CO2 emission, the most important alternative is to produce mineral admixture incorporated cements (CEM II-III-IV-V) instead of portland cement (CEM I). These cements are usually produced by intergrinding the portland cement clinker and the mineral admixtures. However, the difference between grindabilities of the different components of such cements may cause significant effects on the particle size distribution and many other properties. For this reason, separate grinding of additives and clinker may be thought as an alternative. In this study, the effects of intergrinding and separate grinding on the particle size distribution and consequently on the strength of portland composite cements which contained natural pozzolan (trass), granulated blast furnace slag (GBFS) and limestone besides portland cement clinker were studied.

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Libros sobre el tema "Natural limestone"

Tabin Limestone Scientific Expedition (2000). Tabin Limestone Scientific Expedition, 2000: [papers]. Kota Kinabalu: Universiti Malaysia Sabah, 2003.

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Windrum, Andrew. Lincolnshire and Rutland Limestone natural area profile. Peterborough: English Nature, 1997.

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Windrum, Andrew. Lincolnshire and Rutland Limestone natural area profile. Peterborough: English Nature, 1997.

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America, Marble Institute of, ed. Natural stone: Marble, onyx, travertine, granite, quarzite, limestone. 6^a ed. Firenze: Studio Marmo, 2005.

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Gillham, Mary E. Limestone downs: Commons, farms and woods. Bridgend: Glamorgan Wildlife Trust, 1991.

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Hnyk, Peter. Skály a lidé. Červený Kostelec: Pavel Mervart, 2019.

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Gallagher, Teresa Clark. The natural history of Pierrepont State Park and Limestone Preserve, Ridgefield, Connecticut. [Ridgefield, Conn: Town of Ridgefield Conservation Commission, 1991.

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Wickstrom, Lawrence H. Stratigraphy, structure, and production history of the Trenton Limestone (Ordovician) and adjacent strata in northwestern Ohio. Columbus: State of Ohio, Dept. of Natural Resources, Division of Geological Survey, 1992.

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Wolfgang, Tegethoff F., Rohleder Johannes y Kroker Evelyn, eds. Calcium carbonate: From the Cretaceous period into the 21st century. Basel: Birkhäuser Verlag, 2001.

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John, Graves. From a limestone ledge: Some essays and other ruminations about country life in Texas. Houston: Gulf Pub. Co., 1991.

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Capítulos de libros sobre el tema "Natural limestone"

Koch, Roman, Lutz Katzschmann, Klaus Poschlod y Friedrich Häfner. "Muschelkalk Limestone". En Natural Stone and World Heritage, 103–10. London: CRC Press, 2021. http://dx.doi.org/10.1201/9780367823061-22.

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Sahu, Kamal Kishor, Amit P. Multaniya y Manish Kumar Sinha. "Hydro-Geospatial Investigation to Propose Water Conservation Sites for Water Management in Limestone Terrain". En Sustainability of Natural Resources, 106–22. Boca Raton: CRC Press, 2024. http://dx.doi.org/10.1201/9781003303237-7.

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Duarte, Isabel, António Pinho, Luís Lopes, Ricardo Sábio y Micael Jorge. "Subsidence Hazard in Limestone Cavities: The Case of “Grutas da Moeda” (Fátima, Central Portugal)". En Advances in Natural Hazards and Hydrological Risks: Meeting the Challenge, 63–67. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-34397-2_13.

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Rathnarajan, Sundar, Umesh Hule, Radhakrishna G. Pillai y Ravindra Gettu. "Long-Term Natural Carbonation in Concretes with Fly Ash and Limestone Calcined Clay Systems". En International RILEM Conference on Synergising Expertise towards Sustainability and Robustness of Cement-based Materials and Concrete Structures, 1133–40. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-33187-9_105.

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Origenes, Marne G., Noba F. Hilvano, Ren Divien R. Obeña, Jonathan O. Hernandez, Diana Shane A. Balindo, Edelyn O. Echapare y Inocencio E. Buot. "Gender Role In The Conservation And Management Of Forests Over Limestone In Samar Island Natural Park, Philippines". En Proceedings of the 2nd International Conference on Multidisciplinary Sciences for Humanity in Society 5.0 Era (ICOMSH 2022), 11–39. Paris: Atlantis Press SARL, 2023. http://dx.doi.org/10.2991/978-2-38476-204-0_3.

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Koch, Roman y Anette Ritter-Höll. "Jurassic limestones". En Natural Stone and World Heritage, 110–19. London: CRC Press, 2021. http://dx.doi.org/10.1201/9780367823061-23.

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Thornton, E. Lexus, Avery Hartley, Daniel Caudill, Martin Gamesu, Julius Schoop y Fazleena Badurdeen. "Evaluating the Sustainability of Paper and Plastic Substitute Material LimeX". En Lecture Notes in Mechanical Engineering, 1082–90. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-28839-5_120.

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AbstractWith the increasing decline in the environment and natural resources it is important to find new ways in which manufacturing can increase the sustainability of the world. This study seeks to compare LimeX, a state-of-the-art paper and plastic alternative primarily made of limestone, with conventional paper and plastic materials. For a better understanding of LimeX as a material, a brief investigation of the mechanical and chemical properties will be performed through experimentation and analysis. In addition, this paper aims to evaluate the sustainability of LimeX through the analysis of metrics relating to the triple bottom line (environmental impacts, economic impacts and societal impacts) to evaluate and compare the sustainability performance of LimeX products with conventional paper and plastic products. The previously developed Product Sustainability Index (ProdSI) will be adapted and used in this study to conduct the sustainability evaluation. Major findings will include results from an experimental analysis of LimeX via SEM and EDS, and LimeX material property measurements via tensile testing and density measurements. In addition, there will also be a comparison of the sustainability performance of conventional paper and LimeX using a simplified ProdSI. The study found that LimeX was marginally more sustainable than paper, but this evaluation could change with information from the development of a life-cycle analysis report on the material.

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Alperson-Afil, Nira y Naama Goren-Inbar. "Scarce but Significant: The Limestone Component of the Acheulean Site of Gesher Benot Ya'aqov, Israel". En The Nature of Culture, 41–56. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-017-7426-0_5.

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Šťastná, Aneta y Richard Přikryl. "Determination of Source Areas of Natural Stones: A Methodology Approach Applied to Impure Crystalline Limestones". En Materials, Technologies and Practice in Historic Heritage Structures, 157–75. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-2684-2_9.

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Bost, M. y J. Guedon Dubied. "Natural and artificial micro-cracking in limestone". En Preservation of Natural Stone and Rock Weathering, 17–23. Taylor & Francis, 2007. http://dx.doi.org/10.1201/noe0415450188.ch3.

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Actas de conferencias sobre el tema "Natural limestone"

Perriguey, Dustin, Abdul-Mehdi S. Ali y Jose Cerrato. "INVESTIGATION OF METAL REMOVAL USING NATURAL LIMESTONE ROCK". En GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-301802.

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Wang, Fei, Te Li, Toshihiro Kuzuya, Jihua Li y Shinji Hirai. "CO2absorption/release properties of natural limestone ore using TiO2as stabilizers". En International conference on Future Energy, Environment and Materials. Southampton, UK: WIT Press, 2014. http://dx.doi.org/10.2495/feem130341.

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Diaconu, Daniela, Kay Birdsell y George Zyvoloski. "Natural and Engineered Barriers in a Romanian Disposal Site for Low and Intermediate Level Waste". En ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4638.

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The operational waste generated by the Cernavoda Nuclear Power Plant will be disposed in a near-surface facility. The low and intermediate level wastes, containing particularly large concentrations of C-14 and H-3, are treated and conditioned in steel drums, which will be placed in the disposal cells and then immobilized in concrete. The Saligny site has been proposed for LIL waste disposal. Geologically, the main components of this site are the quaternary loess, the Precambrian and pre-quaternary clays, and the Eocene and Barremian limestones. Hydrologically, the site can be divided into a vadose zone down to 45–50m and three distinct aquifers, two of them in the limestone beds and the third into the lenses of sand and limestone existing in the pre-quaternary clay layer. Preliminary performance assessments, presented in this paper, indicate that the geologic layers are efficient natural barriers against water flow and radionuclide migration from the vadose zone to the Barremian aquifer. The semi-arid climate and the low precipitation rate prevent contaminant transport from the disposal site to the Eocene aquifer. FEHM simulations of transient groundwater flow showed that seasonal variations influence the moisture content profile in the top of the vadose zone, but the influence over the long term is not significant for contaminant transport. The Danube River level variations control water movement in the Barremian aquifer, especially in the upper part where the limestone is highly fractured and water moves toward the river when its level is low and toward the site when the river level is high. The disposal concept tries to combine the natural and engineered barriers in order to ensure the safety of the environment and population. Therefore, the concrete filling the disposal cells surrounds the waste with a medium that facilitates C-14 retention by precipitation, thus reducing the C-14 releases in the atmosphere and geosphere.

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AKRAM, Laila. "Fire Induced Microstructural Changes in Local Building Materials: Cases of White Marble and Limestone". En Mediterranean Architectural Heritage. Materials Research Forum LLC, 2024. http://dx.doi.org/10.21741/9781644903117-32.

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Abstract. The aim of this work is to evaluate the degradation state of natural stones after their exposure to fire. These building and decorative materials, widely used in the architectural heritage, suffer irreversible damage when exposed to high temperatures. Therefore, knowledge of their residual durability is crucial in order to determine whether the post-fire building structure should be restored, reinforced or demolished. For this purpose, limestones (calcarenites) and white marbles collected from local quarries were subjected to heating-cooling cycles in a muffle furnace at various temperatures up to 1100°C. After each exposure, the selected samples were characterized at room temperature using X-ray diffraction (XRD), micro-Raman and ATR-FTIR infrared techniques. The results obtained showed that the mineralogical nature of both calcareous and marble natural stones is a key factor in their thermal stability when exposed to high temperatures. Above 570°C, natural stones undergo calcite decarbonation at different temperature ranges. Marble, which is mineralogically monophasic, underwent decomposition at 800°C, similar to calcite in its pure state. Calcarenite was decomposed at a much lower temperature of about 700 °C. This study classifies marble as more thermally stable than calcarenite.

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Schmidt, Jon A., Steven W. Ellsworth, R. Allen Brooks, Darren F. Bishop, Mark G. Bisett, Michael C. Aubele y H. Ed Watkins. "Colonization and Habitat Use by Marine Fish and Epifauna of the Gulfstream Pipeline Habitat Replacement Structures". En 2006 International Pipeline Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/ipc2006-10374.

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Gulfstream Natural Gas System, L.L.C. (Gulfstream) constructed a 36-inch-diameter pipeline in 2001 to transport natural gas from plants in Mississippi and Alabama to markets in central and southern Florida. The route of the marine portion of the pipeline originates from the shoreline of Mississippi and Alabama in Mississippi Sound and transverses the Gulf of Mexico, making landfall in Tampa Bay. Activities such as the installation of the pipe on the seafloor, the subsequent lowering of the pipe beneath the seafloor, and the mooring of construction vessels used in these processes were anticipated to disturb the seafloor and associated resources. Compensatory mitigation for project impacts to live hard-bottom was undertaken with the installation of habitat replacement sites consisting of either limestone boulder groupings or pre-fabricated reef modules. As part of the mitigation monitoring plan, Gulfstream has documented the success of the limestone’s placement and stability within the habitat replacement sites, monitored colonization by sessile epifauna, and censused the reef fish populations found utilizing the created habitat. The monitoring protocol includes diver collected still photography and Bohnsack point counts for fish. The created habitat provides a greater amount of habitat relief/complexity than natural hard/live bottom and is thriving in terms of both the recruitment of sessile epifauna and habitat use by a diverse demersal and commercially important fish community. Thus the limestone boulder and reef module areas created as part of the Gulfstream project appear to be a very successful means of habitat mitigation.

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Sharma, Pranjal, Sayantan Ghosh, Nitin Joshi y Dilip Kumar Srivastava. "Natural fracture parameterization and connectivity in Rohtas Limestone, Vindhyan Basin, Central India". En MACHINE LEARNING AND INFORMATION PROCESSING: PROCEEDINGS OF ICMLIP 2023. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0168892.

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Gugule, Sanusi, Deitje Adolfien Katuuk, Feti Fatimah y Chaleb Paul Maanari. "Characterization of Calcined Lobong Limestone". En Unima International Conference on Science and Technology 2022. Switzerland: Trans Tech Publications Ltd, 2023. http://dx.doi.org/10.4028/p-67y2nb.

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This study aims to produce and characterize CaO (calcium oxide) from limestone, a natural product of Lobong Village. Calcination is the thermal decomposition of limestone to remove carbon so that it can produce calcium oxide. One of the functions of CaO is as an eco-friendly catalyst that does not produce toxic or hazardous waste and can be reused. CaO resulting from the calcination process at a temperature of 900°C for 1.5 h was characterized using XRD, SEM, FTIR, and EDS. XRD analysis of calcined limestone produced 2θ (h k l) diffraction peaks, namely 32.228o (1 1 1), 37.389o (2 0 0), 53.864o (2 2 0), 64.169o (3 1 1), and 67.404o (2 2 2) which indicates the dominance of CaO. SEM analysis shows that the morphological structure of Lobong limestone after calcination is more porous than before. Studies by FTIR show that the chemical bonds of carbonate groups in the calcined limestone are decreasing. EDS analysis also shows that the mapping of carbon, which forms carbonates in calcined limestone, is decreasing.

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"Limestone Modified Cement for High-Performance Concretes". En "SP-178: Sixth CANMET/ACI/JCI Conference: FLy Ash, Silica Fume, Slag & Natural Pozzolans in Concrete". American Concrete Institute, 1998. http://dx.doi.org/10.14359/6024.

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North, Vanya y Stephen K. Boss. "THE HUMAN NATURAL RESOURCE ENDOWMENT OF LIMESTONE AND THE LIMITS OF CEMENT PRODUCTION". En GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-369118.

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"Mixture Proportioning for Highly-Flowable Concrete Incorporating Limestone Powder". En "SP-153: Fly Ash, Silica Fume, Slag, and Natural Pozzolans in Concrete Proceedings Fifth International Conference Milwauk". American Concrete Institute, 1995. http://dx.doi.org/10.14359/1073.

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Informes sobre el tema "Natural limestone"

Juday, G. P. Alaska research natural areas: 2. Limestone jags. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 1989. http://dx.doi.org/10.2737/pnw-gtr-237.

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Herring, Theodore, Justin Tweet y Vincent Santucci. Wind Cave National Park: Paleontological resource inventory (public version). National Park Service, junio de 2023. http://dx.doi.org/10.36967/2299620.

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Wind Cave National Park (WICA), the first cave in the world to become a national park, is famous for the park’s namesake feature. Wind Cave, named for the noticeable wind-flow patterns observed as air moves in and out of the natural cave entrance, is currently the third longest cave system in the United States and seventh longest in the world. Wind Cave formed when groundwater dissolved buried layers of the fossiliferous Madison Limestone, which were deposited during the Mississippian subperiod approximately 359 to 347 million years ago. In addition to the Madison Limestone, several other formations are exposed within the park, dating from the early Proterozoic to the Holocene. The presence of fossils within the park has been known since at least the late 19th century when early settlers explored the cave to turn the geologic feature into a tourist attraction. However, most of the geologic work conducted during the park’s history has focused on the exploration and development of the cave itself, rather than its fossils. Paleontology became a bigger focus in the late 20th century when the park partnered with the South Dakota School of Mines and Technology to recover and research fossils found within the cave and on the park’s surface. Other partnerships include those with the Mammoth Site of Hot Springs and Northern Arizona University, through which researchers have studied Quaternary cave deposits found across the park. In ascending order (oldest to youngest), the geologic formations at WICA include undifferentiated lower Proterozoic rocks (Precambrian), Harney Peak Granite (Precambrian), Deadwood Formation (Cambrian–Ordovician), Englewood Limestone (Devonian–Mississippian), Madison Limestone (Mississippian), Minnelusa Formation (Pennsylvanian–Permian), Opeche Shale (Permian), Minnekahta Limestone (Permian), Spearfish Formation (Permian–Triassic), Sundance Formation (Middle–Upper Jurassic), Unkpapa Sandstone (Upper Jurassic), Lakota Formation (Lower Cretaceous), Fall River Formation (Lower Cretaceous), White River Group (Eocene–Oligocene), and Quaternary alluvium, conglomerate, and gravel deposits. The units that are confirmed to be fossiliferous within the park are the Deadwood Formation, Englewood Limestone, Madison Limestone, and Minnelusa Formation, which contain a variety of marine fossils from a shallow sea deposition environment; the Sundance Formation, which has much younger marine fossils; the Lakota Formation, which has yielded petrified wood; and the White River Group and Quaternary deposits, which contain vertebrate and invertebrate fossils deposited in and near freshwater streams, lakes, and ponds. Many of the fossils of WICA are visible from or near public trails and roads, which puts them at risk of poaching or damage, and there is evidence that fossil poaching occurred at several of the Klukas sites soon after they were discovered. Furthermore, there are several fossil sites on the tour routes within Wind Cave, which are of value to interpretation and the park experience. WICA has implemented cyclic fossil surveys in the past to monitor site conditions, and it is recommended that this paleontological resource monitoring be continued in the future.

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