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Showing 1 to 19 of 19 for “"Fluoride concentration"”.
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Flúor í íslenskum hrossum
Fluoride in the environment distributes to water and vegetation from both natural and industrial sources. Vertebrates exposed to high levels of fluoride, accumulate fluoride in calcified tissues of the body, and are in danger of developing either acute or chronic symptoms of fluoride toxicity. The …
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Fluoride varnish concentration gradient effects measured by quantitative light fluorescence
Two of the three fluoride varnishes sold on the American market today are sold in 10-ml tubes of 5.0-percent NaF varnish (Duraphat and Duraflor). Pilot studies have shown that a separation of contents within these tubes exists. The purpose of the current study was four-fold: 1) to measure the …
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Aluminium smelting cell control and optimisation
… in the long term, for mature cells the aluminium fluoride consumption is fairly accurately reflected by the soda and calcium oxide contents of the primary alumina. Therefore the poor control of aluminium fluoride concentration reflects the poor understanding of the causes of variation in aluminium …
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Conversion kinetics of oxyfluoride-derived YBCO films
… to crystalline YBCO films. In this approach, the concentration of residual fluoride in the partially converted films was examined using fluoride ion selective electrode. Results obtained by this method were compared to results obtained by such methods as X-ray analysis and in-situ resistivity …
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Defluoridation of typical eastern Virginia groundwater
… Agency Maximum Contaminate Level (MCL) for fluoride. This thesis explores the use of alum and alum and lime for the reduction of fluoride to the MCL or lower. In order to reduce an initial fluoride concentration of 2.1 mg/l to 1.8 mg/l 125 mg/l alum was required, for reduction from 5.5 mg/l …
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Treatment of dentine hypersensitivity using desensitising toothpastes
… such as the application ofDuraphat, a high fluoride concentration varnish such a Duraphat; Seal and Protect, a resin based varnish; fluoride trays or solutions in conjunction with iontophoresis; or use oflow-level laser therapy. As desensitising dentifrices are so easy to access, inexpensive …
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Mineral Content of Water From Public Fountains Along the Monon Trail in Central Indiana
… it compares with commonly used bottled water. Fluoride is added to tap water in many communities in the US for the prevention of dental caries (community water fluoridation). However, whether water provided by these fountains meets the recommended fluoride level by the CDC for caries prevention …
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Tooth lesions and fluoride content in teeth, bones and antlers of mule deer (Odocoileus hemionus)
… have been associated with high ingestion of fluorides. The present study compared prevalence and severity of tooth lesions with fluoride content in teeth, bones and antlers of mule deer from USAF A with deer from other two areas in Colorado. Mule deer tissues were collected during 1993-1995 …
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Fabrication of Macadamia Nutshell Powder-AI/Fe Metal Oxide Modified Diatomaceous Earth Composite Beads for Fluoride and Pathogen Removal Groundwater
Contamination of drinking water due to fluoride and pathogens is a severe health hazard problem. Excess of fluoride (>1.5 mg/L) in drinking water leads to dental and skeletal fluorosis whereas the presence of pathogens in water can lead to adverse health effects, including gastrointestinal illness, …
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Molecular Probes for Biologically Important Molecules: A Study of Thiourea, Hydroxyl radical, Peroxynitrite and Hypochlorous acid
… studied using appropriate analytical techniques. Fluoride is an important species in human physiology. It strengthens teeth and gives protection against dental caries. However, elevated concentrations of fluoride in the body can lead to health problems such as dental and skeletal fluorosis. …
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Development of Novel Liquid Chromatography-Electrospray Tandem Mass Spectrometry Approaches for the Structural Characterization of Brevetoxins Including in vitro Metabolites
… experiments, the addition of ammonium fluoride resulted in the formation of the ammonium adduct or protonated brevetoxin with a concomitant decrease of the sodium adduct peak. Product ion spectra of [M + NH4]+ and [M + H]+ were similar and provided useful structural information. The …
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Chromic acid anodized Ti-6Al-4V: its characterization and its single lap bond strength to heat resistant adhesives
… chemically degraded by the unnecessarily high fluoride concentration in the oxide from the higher current density. Lica® 44 titanate primer did not significantly influence bond strength or durability, except when unfilled polyetherimide was the adhesive. Polyphenylquinoxaline bond processing …
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Fabrication of metal-oxide modified porous ceramic granules from aluminosilicate clay soils for defluoridation of groundwater
… for rural communities are reported to have high fluoride concentration, much above the WHO guideline of 1.5 mg/L. This study aimed at activating aluminosilicate clay soil mechanochemically, modifying aluminosilicate clay soil with Al-oxide and fabricating porous ceramic granules using Al-oxide …
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Selective fluoride removal by aluminum precipitation & membrane filtration
Fluoride is an anionic constituent of most natural surface and ground waters. At low concentrations it has the beneficial effect of improving dental health, but at high concentrations it causes skeletal and other problems. The drinking water standard for fluoride is 4.0 mg/L, but even at this level …
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Defluoridation using modified mucilage from indigenous plant material in Vhembe District, Limpopo Province, South Africa
… as another source of water has elevated fluoride levels exceeding the World Health Organisation permissible limit of 1.5 mg/L in some regions around the world. This study aims to apply aluminium (AlDE) and magnesium modified (MgDE) Dicerocaryum eriocarpum (DE) leaves mucilage as …
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Morphological and Mechanical Properties of Dispersion-Cast and Extruded Nafion Membranes Subjected to Thermal and Chemical Treatments
… degradation had a tremendous effect on the fluoride release rate and chemical degradation kinetics. By exchanging the membranes into the Na+ form, thermal degradation was avoided, allowing us to study the role of crystallinity as a function of fluoride release. Ultimately, Nafion® …
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Intra-familial Cariological Studies on a Saudi Population
… the effects of six weeks’ use of a 5,000 ppm fluoride toothpaste on caries-related factors in dental plaque and saliva and 5) consecutively assess the caries risk following six weeks’ use of 5,000 ppm fluoride toothpaste using the “Cariogram”. Materials and methods: A total of 258 individuals …
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Synthesis of Zr4+/Ag+ metal oxides modified zeolite for application in fluoride and pathogens removal from water
… is often contaminated with high levels of fluoride and pathogens, posing a significant health risk. This dissertation aims to synthesize Zr4+/Ag+ metal oxides modified zeolite adsorbent for use in fluoride and pathogens removal from water. The first section of this research aimed at …
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Schutzwirkung eines hochkonzentrierten Fluoridgels gegen erosiven und erosiv-abrasiven Zahnschmelzverlust
Ziel dieser Studie war es, den maximal erreichbaren Schutz des Zahnschmelzes nach Erosion und Erosion in Verbindung mit Abrasion durch hochkonzentriertes Fluoridgel mit zusätzlichem Fluorid aus Zahnpasta zu ermitteln. 36 Rinderzahnschmelzproben wurden täglich sechsmal alle zwei Stunden für 30 s …