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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Modeling and evaluation of granular limestone dry scrubbing processes

Chattopadhyay, Sandip January 1992 (has links)
No description available.
132

The stratigraphy and areal geology of Flint Ridge

Turkopp, John January 1915 (has links)
No description available.
133

A study of standards for the evaluation of ground limestone on the basis of fineness

Bigger, Theodore Cuyler January 1948 (has links)
Fifty-four samples of calcitic and dolomitic limestone ground by 21 Virginia companies to a fineness whereby not less than 95 percent would pass through a No. 10 sieve were collected and mechanically separated. The cumulative percentage of the material passing sieve Nos. 10, 20, 40, 60, 100, and 140 was recorded to determine if recommendations are justified on the basis of the percentage of ground limestone passing through a single sieve. A recommendation often used by Agronomists is based on all the material passing a No. 10 sieve with none of the finer particles removed. For this recommendation to be reliable, the percentage of material passing No.10 sieve uniformly should also pass the finer sieves uniformly. The analyses of the 54 samples were divided into five grades of fineness by accepting the cumulative percentage passing sieve Nos. 10 and 100 as standards and the grades were compared graphically. A study has been made of the work done by previous investigators in which they established standards for the evaluation of ground limestone on the basis of fineness. Generally, investigators believed that much of the material failing to pass through No. 10 sieve is too coarse to be any value for a number of years after being added to the soil, but the material passing through a No. 100 sieve will exert its maximum effect soon after incorporation with the soil. To crush agricultural limestone much finer than required for all the product to pass a No. 10 sieve is generally considered uneconomical. As a result of this investigation, the following conclusions are presented: Of the 54 samples separated to determine the cumulative percentage passing No. 100 sieve, 2 fell between 0-20 percent, 11 between 20-40 percent, 25 between 40-60 percent, 11 between 60-80 percent, 4 between 80-95 percent, and 1 with 97 percent. Between 95 and 100 percent of each sample passed No. 10 sieve, while the amount that passed No. 100 sieve varied between 16 and 97 percent. Accuracy in evaluating ground limestone on the basis of fineness was increased by knowing the percentage of material that passed No. 100 sieve in addition to the percentage of material that passed No. 10 sieve. / M.S.
134

Micropaleontology and paleogeography of the Upper Mural Limestone of southeastern Arizona and northern Sonora

Rosales Dominguez, Maria del Carmen, 1959- January 1989 (has links)
No description available.
135

Sequence stratigraphy and structure of the tertiary limestones in the Gulf of Papua, Papua New Guinea

Morgan, Glenn Douglas, School of Biological, Earth & Environmental Science, UNSW January 2005 (has links)
A sequence stratigraphic study was conducted on the Mendi and Darai Limestone Megasequences in the foreland area of the Papuan Basin in Papuan New Guinea. It involved the integrated use of seismic, wireline log, well core and cuttings, strontium isotope age and biostratigraphic data. This study enhanced the understanding of the structure, stratigraphy and depositional architecture of the limestones, and the morphology of the basin at the time of deposition. The results of the study were integrated with published geological and tectonic models for the Papuan Basin to develop a consistent and coherent model for the depositional history of the limestones. Eleven third-order sequences were delineated within the Mendi and Darai Limestone Megasequences. Eight depositional facies were interpreted across these sequences, namely deep-shelf, shallow-shelf, backreef, reef, shoal, forereef, basin margin and submarine fan facies. Each facies was differentiated according to seismic character and geometry, well core and cuttings descriptions, and its position in the depositional framework of the sequence. Deposition of the Mendi Limestone Megasequence commenced in the Eocene in response to thermal subsidence and eustatic sea-level rise. Sedimentation comprised open-marine, shallow-water, shelfal carbonates. During the middle of the Oligocene, the carbonate shelf was exposed and eroded in response to the collision of the Australian and Pacific Plates, or a major global eustatic sea-level fall. Sedimentation recommenced in the Late Oligocene, however, in response to renewed extensional faulting and subsidence associated with back-arc extension. This marked the onset of deposition of the Darai Limestone Megasequence in the study area. The KFZ, OFZ and Darai Fault were reactivated during this time, resulting in the oblique opening of the Omati Trough. Sedimentation was initially restricted to the Omati Trough and comprised deep and shallow-marine shelfal carbonates. By the Early Miocene, however, movement on the faults had ceased and an extensive carbonate platform had developed across the Gulf of Papua. Carbonate reef growth commenced along topographic highs associated with the KFZ, and led to the establishment of a rimmed carbonate shelf margin. Shallow to locally deeper-marine, shelfal carbonates were deposited on this shelf, and forereef, submarine fan and basin margin carbonates were deposited basinward of the shelf margin. The Uramu High and parts of the Pasca High became submerged during this time and provided sites for pinnacle reef development. During the middle of the Early Miocene, a major global eustatic sea-level fall or flexure of the Papuan Basin associated with Early Miocene ophiolite obduction subaerially exposed the carbonate shelf. This resulted in submarine erosion of the forereef and basin margin sediments. Towards the end of the Early Miocene, however, sedimentation recommenced. Shallow-marine, undifferentiated wackestones and packstones were deposited on the shelf; forereef, submarine fan and basin margin sediments were deposited basinward of the shelf margin; and reef growth recommenced along the shelf margin and on the Pasca and Uramu Highs. By the end of the Early Miocene, however, the pinnacle reef on the Pasca High had drowned. During the middle of the Middle Miocene, subtle inversion associated with ophiolite obduction subaerially exposed the carbonate shelf, and resulted in submarine erosion of the forereef and basin margin sediments. Sedimentation recommenced towards the end of the Middle Miocene, however, in response to eustatic sea-level rise and flexure of the crust associated with foreland basin development. Shallow marine, undifferentiated wackestones, packstones and grainstones were deposited on the shelf; carbonate shoals were deposited along the shelf margin; and forereef, submarine fan and basin margin carbonates were deposited basinward of the shelf margin. Carbonate production rapidly outpaced accommodation space on the shelf during this time, resulting in highstand shedding and the development of a large prograding submarine fan complex basinward of the shelf margin. By the Late Miocene, carbonate deposition had ceased across the majority of the study area in response to a major global eustatic sea-level fall or inversion associated with terrain accreation events along the northern Papuan margin. Minor carbonate deposition continued on parts of the Uramu High, however, until the middle of the Late Miocene. During the latest Miocene, clastic sediments prograded across the carbonate shelf, infilling parts of the foreland basin. Plio-Pleistocene compression resulted in inversion and erosion of the sedimentary package in the northwestern part of the study area. In the southeastern part of the Papuan Basin, however, clastic sedimentation continued to the present day.
136

Biological growth on the Alamo

Gallagher, Casey Amber 21 November 2013 (has links)
The limestone façade of the Alamo shows several areas of biological growth with black and gray streaks and blotches discoloring the stone. This thesis investigates the identity of the microorganisms on the stone, using two: DNA identification, and lab cultures grown from samples of the biofilm. By using both approaches, a better understanding was gained of the range of organisms present. Through these tests, it was found that the dominant organism on the limestone is cyanobacteria, of the genus Chrooccocus. Lab cultures revealed other organisms, including possibly fungi photobionts and algae. Through analysis and comparison of historic and contemporary photographs, patterns of recolonization are investigated. To further understand the effects of the biocide treatments, cultured samples were treated, and their reactions monitored. To better understand the possible relationship between the Alamo stone and its colonizing organisms, physical properties of the stone were investigated. SEM images, Edax minerology and water absorption were used to characterize the stone. This study is the first of its kind to investigate Native Texas quarried architectural limestone. Although studies have been conducted on historic monuments around the world to identify biological growth, none have focused on Texas limestone. By using both DNA and lab culture identification, this study adds to a wealth of investigations of other conservation professionals, applying it to a subject that has not been studied in this way before. By understanding the colonizing organisms, a sustainable conservation regimen can be determined. / text
137

A lithologic investigation of the Schroyer limestone in Geary, Pottawatomie and Riley Counties, Kansas

Stewart, John W. January 1963 (has links)
Call number: LD2668 .T4 1963 S85 / Master of Science
138

The geology of the building stone of Cedar Park and vicinity

Barrow, Leonidas Theodore 07 November 2012 (has links)
Not available / text
139

Momento de aplicação de calcário e gesso em um latossolo vermelho distrófico, no desenvolvimento inicial do milho /

Manetti, Fábio Augusto, 1977- January 2005 (has links)
Orientador: Dirceu Maximino Fernandes / Banca: Roberto Lyra Villas Bôas / Banca: Carlos Sérgio Tiritan / Resumo: Com a finalidade de avaliar os efeitos do momento da aplicação isolados e conjuntos do calcário e do gesso no crescimento vegetativo de plantas de milho. O experimento foi instalado em casa de vegetação e conduzido na área experimental do Departamento de Recursos Naturais - Ciência do Solo, localizado na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas - FCA da Universidade Estadual Paulista - UNESP, Campus de Botucatu, em um Latossolo Vermelho Distrófico, textura média, Unidade Patrulha. Os tratamentos foram:- T1- sem calcário calcítico e sem gesso (testemunha); T2 - com calcário calcítico e sem gesso; T3 - sem calcário calcítico e com gesso; T4 - calcário calcítico aplicado 30 dias antes da aplicação do gesso; T5 - calcário calcítico aplicado 15 dias antes da aplicação do gesso; T6 - calcário calcítico aplicado junto ao momento de aplicação do gesso (mistura); T7 - calcário calcítico aplicado 15 dias após a aplicação do gesso; T8 - calcário calcítico aplicado 30 dias após a aplicação do gesso; T9 - calcário calcítico e gesso (mistura) aplicado na superfície 30 dias antes da semeadura (das); T1- sem calcário dolomítico e sem gesso (testemunha); T2 - com calcário dolomítico e sem gesso; T3 - sem calcário dolomítico e com gesso; T4 - calcário dolomítico aplicado 30 dias antes da aplicação do gesso; T5 - calcário dolomítico aplicado 15 dias antes da aplicação do gesso; T6 - calcário dolomítico aplicado junto ao momento de aplicação do gesso (mistura); T7 - calcário dolomítico aplicado 15 dias após a aplicação do gesso; T8 - calcário dolomítico aplicado 30 dias após a aplicação do gesso; T9 - calcário dolomítico e gesso (mistura) aplicado na superfície 30 dias antes da semeadura (das). Esses tratamentos foram aplicados nos três primeiros anéis de 7,0 cm cada, totalizando 21 cm, de colunas de PVC de...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With the purpose to appraise the effects of the superposition, isolated and together, of the limestone and the gypsum in the vegetative growth of maize plants, to the forty days after the emergence, as well as in the extraction of the nutrients by the aerial portion of the plants, beyond its effects on the behavior of some chemical features from the superficial layer of the soil, was accomplished this study. The experiment had been settled and guided at the experimental area on Natural Resources Department - Soil Science, located in the Experimental Farm "Lageado", of the "Faculdade de Ciências Agronômicas - FCA - from "Universidade Estadual Paulista - UNESP, Campus of Botucatu, in a dystrophic clayey Rhodic Hapludox, average texture, "Unidade Patrulha".The treatments had been defined by the moments of the applications of the two types of limestones, calcitic and dolimitic, with and without gypsum and agricultural gypsum only. These treatments had been applied in three first rings of 7,0cm each, totalizing 21cm, from PVC columns of 49cm of height and 10cm of diameter. The experimental outlining had been made in blocks, in factorial arrangement of 9x2, with four repetitions.The harvest had been made to the forty days after the emergence, having been the plants cut close to the soil and measured like: heights from the stalk's base to the first sheath and the edge of the biggest leaf; stalk's diameter; numbers of leafs for plants; fresh and dry matter...(Complete abstract click electronic access below) / Mestre
140

Influence of rock salt impurities on limestone aggregate durability

Varner, Jonathan January 1900 (has links)
Master of Science / Department of Civil Engineering / Kyle Riding / Some limestone coarse aggregate in concrete pavement can break down under repeated freeze-thaw cycles. Application of rock salt may increase the severity of exposure conditions because of trace compounds, such as calcium sulfate, in rock salt. Subsequently, limestone aggregate in concrete was subjected to freeze-thaw cycling in two methods: salt-treating the aggregate before batching concrete, and half-immersing concrete specimens in rock salt solution during freeze-thaw cycling. Concrete and saw-cut limestone specimens were also subjected to wet-dry cycles in varying salt solutions to examine the influence of trace compounds in rock salt. Freeze-thaw test results indicate that the test methods used were not severe enough to determine if a limestone aggregate was durable or not. The wet-dry testing was also not severe enough to determine the effects of trace compounds in salt solution.

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