نتایج جستجو برای: limestone mines

تعداد نتایج: 12941  

2004
Claude E. Boyd

Three techniques for treating fish ponds with agricultural limestone were evaluated in ponds with clayey soils in Brazil and in ponds with sandy soils in South Africa. Amounts of agricultural limestone equal to the lime requirement of bottom soils were applied by the following methods to each of three ponds: (1) direct application over the pond surface; (2) spread uniformly over the bottom of t...

2012
P. C. Okonkwo

The kinetics of calcination of a high calcium type of limestone was studied. Ukpilla limestone found in the central region of Nigeria was studied. The limestone composition shows that the limestone has 51.29% calcium oxide and 41.53% loss on ignition and magnesium oxide content of 2.23%. The following parameters were determined; diffusion coefficient of lime layer, and mass transfer coefficient...

2010

The study of faulting and earthquake processes requires direct and near-fi eld observations at the focal depth. Deep mines provide a unique opportunity to make such observations. The linked DAFSAM (Drilling Active Faults Laboratory in South African Mines)-NELSAM (Natural Earthquake Laboratory in South African Mines) projects focus on building an earthquake laboratory in deep gold mines in South...

Journal: :Environmental Health Perspectives 1993
R J Srám L Dobiás P Rössner D Veselá D Veselý R Rakusová V Rericha

Recent data from deep uranium mines in Czechoslovakia indicated that mines are exposed to other mutagenic factors in addition to radon daughter products. Mycotoxins were identified as a possible source of mutagens in these mines. Mycotoxins were examined in 38 samples from mines and in throat swabs taken from 116 miners and 78 controls. The following mycotoxins were identified from mines sample...

Journal: :Journal of occupational and environmental medicine 2016
Marric Buessing Leslie I Boden

OBJECTIVE The aim of this study was to test for differences in injury rates for contractor-operated underground coal mines relative to owner-operated mines in Kentucky, controlling for other covariates. METHODS We used disparities between MSHA contractor data and surface reclamation permit data to identify mines operated by contractors. We then used negative binomial regression to estimate in...

1999
P. W. MORCOMBE R. L. PEET R. H. JACOB

Fifty Merino weaner sheep grazing on a wheat stubble at Wongan Hills were fed ad lib. either oat grain mixed with limestone (2% w/w) or just oat grain during the summer and autumn of 1985. The addition of limestone to the oat supplement increased the growth of the sheep from 39 g/day to 83 g/day (P<O.OOl) during the first 70 days of feeding. A summer thunderstorm resulted in a brief germination...

2006

It has long been known that ventilation is a costeffective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/nonmetal operations in the United St...

2014
Navdeep Kaur Dhami M. Sudhakara Reddy Abhijit Mukherjee

Since ages, architects and artists worldwide have focused on usage of durable stones as marble and limestone for construction of beautiful and magnificent historic monuments as European Cathedrals, Roman, and Greek temples, Taj Mahal etc. But survival of these irreplaceable cultural and historical assets is in question these days due to their degradation and deterioration caused by number of bi...

2017
JOHN R. WHITE

Analyses of samples of the raw materials locally available for use in the Eaton (Hopewell) Furnace indicate that the iron ore and bituminous coal were of good smelting quality while the limestone (flux) was not. The limestone had a much higher then desirable silica content and a low calcium content. The limestone was insufficient to the task of removing impurities introduced through the fuel co...

Journal: :Applied sciences 2021

In this study, we developed a system to collect and analyze log data related truck travel times in underground mines using Bluetooth beacons tablet computers. When signal from installed at major mine is received by truck-mounted computer, the beacon information collected uploaded cloud server. A processing program integrates files into single file, calculating statistical values for each sectio...

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