scholarly journals Geospatial Variability Analysis of Fluoride Quantification in Underground Aquifers of Central Parts of Haryana State, India

2021 ◽  
Vol 13 (3) ◽  
pp. 951-959
Author(s):  
P. Bhardwaj ◽  
A. Awasthi ◽  
J. Singh
Keyword(s):  
Fluoride Concentration ◽  
Ground Level ◽  
Underground Water ◽  
High Concentration ◽  
Basement Rocks ◽  
Geological Factors ◽  
Below Ground ◽  
Different Depths ◽  
Water Fluoride ◽  
Phosphatic Fertilizers

The elevated levels of fluoride in underground water enhance the prevalence of the fluorosis epidemic in Haryana state. To assess the groundwater geospatial variability of fluoride at different depths in central parts of Haryana, the present study has been explored.  The samples at eight sites were collected in triplicate at 3 depth levels viz. a) < 10 m below ground level (bgl), b) 10-40 m bgl, and c) > 40 m bgl. Fluoride levels have been determined by the SPADANS-zirconyl oxychloride method using UV-VIS spectrophotometer (Systronics-118). The fluoride concentration varies from 0.19 mg/L to 2.87 mg/L. More than 38 percent of samples exceed the standard prescribed limit of 1.0 mg/L fluoride in drinking water. Fluoride contamination increases in post-monsoon samples with maximum concentration at 40 bgl depth. Due to geological factors (fluoride-bearing minerals in basement rocks) and human-induced (brick-kiln industries, phosphatic fertilizers) factors, a high concentration of fluoride in groundwater is observed. Sustainable defluoridation techniques and a good diet (calcium & vitamin c enriched) can control the adverse effects of fluorosis.

scholarly journals Spatial Analysis (Measurements at Heights of 10 m and 20 m above Ground Level) of the Concentrations of Particulate Matter (PM10, PM2.5, and PM1.0) and Gaseous Pollutants (H2S) on the University Campus: A Case Study

Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 62
Author(s):  
Robert Cichowicz ◽  
Maciej Dobrzański
Keyword(s):  
Spatial Distribution ◽  
Hydrogen Sulfide ◽  
Particulate Matter ◽  
Air Quality ◽  
Spatial Analysis ◽  
Ground Level ◽  
Leeward Side ◽  
High Concentration ◽  
Above Ground Level ◽  
High Concentrations

Spatial analysis of the distribution of particulate matter PM10, PM2.5, PM1.0, and hydrogen sulfide (H2S) gas pollution was performed in the area around a university library building. The reasons for the subject matter were reports related to the perceptible odor characteristic of hydrogen sulfide and a general poor assessment of air quality by employees and students. Due to the area of analysis, it was decided to perform measurements at two heights, 10 m and 20 m above ground level, using measuring equipment attached to a DJI Matrice 600 unmanned aerial vehicle (UAV). The aim of the measurements was air quality assessment and investigate the convergence of the theory of air flow around the building with the spatial distribution of air pollutants. Considerable differences of up to 63% were observed in the concentrations of pollutants measured around the building, especially between opposite sides, depending on the direction of the wind. To explain these differences, the theory of aerodynamics was applied to visualize the probable airflow in the direction of the wind. A strong convergence was observed between the aerodynamic model and the spatial distribution of pollutants. This was evidenced by the high concentrations of dust in the areas of strong turbulence at the edges of the building and on the leeward side. The accumulation of pollutants was also clearly noticeable in these locations. A high concentration of H2S was recorded around the library building on the side of the car park. On the other hand, the air turbulence around the building dispersed the gas pollution, causing the concentration of H2S to drop on the leeward side. It was confirmed that in some analyzed areas the permissible concentration of H2S was exceeded.

scholarly journals Urinary fluoride excretion in children exposed to fluoride toothpaste and to different water fluoride levels in a tropical area of Brazil

2008 ◽  
Vol 19 (3) ◽  
pp. 214-218 ◽  
Author(s):  
Franklin Delano Soares Forte ◽  
Suzely Adas Saliba Moimaz ◽  
Fábio Correia Sampaio
Keyword(s):  
Dental Fluorosis ◽  
Fluoride Concentration ◽  
Second Phase ◽  
Appropriate Use ◽  
Fluoride Toothpaste ◽  
Tropical Area ◽  
Significant Difference ◽  
Urinary Fluoride ◽  
The City ◽  
Water Fluoride

The aim of this study was to evaluate the urinary fluoride excretion of 2- to 7-year-old children exposed to different water fluoride concentrations in the city of Catolé do Rocha, PB, Brazil. Forty-two children were allocated to 3 groups according to the concentration of fluoride in the water: G1 (n=10; 0.5-1.0 ppm F), G2 (n=17; 1.1-1.5 ppm F) and G3 (n= 15; >1.51 ppm F). The study was carried out in two 1-week phases with 1-month interval between the moments of data collection: in the first phase, the children used a fluoride toothpaste (FT) (1,510 ppm F) for 1 week, whereas in the second phase a non-fluoride toothpaste (NFT) was used. The urine was collected in a 24-h period in each week-phase according to Marthaler's protocol. The urinary fluoride excretion data expressed as mean (SD) in µg/24 h were: G1-FT= 452.9 (290.2); G1-NFT= 435.1 (187.0); G2-FT= 451.4 (224.0); G2-NFT= 430.3 (352.5); G3-FT=592.3 (390.5); and G3-NFT=623.6 (408.7). There was no statistically significant difference between the water fluoride groups, and regardless of the week phase (ANOVA, p>0.05). The use of fluoride toothpaste (1,510 ppmF) did not promote an increase in urinary fluoride excretion. There was a trend, though not significant, as to the increase of urine fluoride concentration in relation to fluoride concentrations in the water. The excretion values suggest that some children are under risk to develop dental fluorosis and information about the appropriate use of fluoride is necessary in this area.

scholarly journals Feature space of the Atasu type deposits (Сentral Kazakhstan)

2020 ◽  
pp. 5-10
Author(s):  
N. S. Askarova ◽  
A. T. Roman ◽  
V.S. Portnov ◽  
A.N. Kpobayeva
Keyword(s):  
Feature Space ◽  
Ore Deposits ◽  
Mineral Deposits ◽  
Complex Composition ◽  
Lower Carboniferous ◽  
Geological Factors ◽  
Close Time ◽  
Different Depths ◽  
Geological Formations ◽  
Visean Stage

Purpose. Studying geological formations of the Atasu type deposits to identify prospecting criteria. Methodology. Analysis of literature and fund materials, comparative analysis of geological factors characteristic of stratiform ores, stage formation and metamorphism. Findings. The main features characteristic of the deposits of the Atasu type have been formed: their belonging to the lower strata of the Upper Famennian, Upper Devonian to the Visean stage of the Lower Carboniferous; complex composition of ferromanganese and polymetallic ores formed in three hydrothermal stages (sedimentary, metasomatic and vein ones), stratiform, lenticular, localized near volcanic edifices. Originality. The main geological criteria have been established that determine the belonging of the Uspensky ore belt in Central Kazakhstan deposits to the stratiform deposits of the Atasu type formed at different depths in continental rift valleys. The criteria include the age interval of the formation of ore deposits of the stratiform type, hydrothermal staging of mineralization (sedimentary, metamorphic, metamorphic (hydrothermal, dislocation multistage and dynamothermal)); localization of folded and post-folded subvolcanic intrusions near former volcanic edifices. Practical value. The main prospecting geological criteria (features) established for the Atasu type deposits can be used to form a feature space for predicting the areas of mineral deposits localization of the Uspensky ore belt of Central Kazakhstan formed in close time periods, in similar geological-geochemical, thermodynamic and geodynamic conditions.

scholarly journals A Hotspot of Arid Zone Subterranean Biodiversity: The Robe Valley in Western Australia

Diversity ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 482
Author(s):  
Huon L. Clark ◽  
Bruno A. Buzatto ◽  
Stuart A. Halse
Keyword(s):  
Western Australia ◽  
Arid Zone ◽  
Ground Level ◽  
Ore Formation ◽  
Monitoring Wells ◽  
Groundwater Aquifers ◽  
Species Lists ◽  
Below Ground ◽  
Drill Holes ◽  
Mining Exploration

Knowledge of subterranean fauna has mostly been derived from caves and streambeds, which are relatively easily accessed. In contrast, subterranean fauna inhabiting regional groundwater aquifers or the vadose zone (between surface soil layers and the watertable) is difficult to sample. Here we provide species lists for a globally significant subterranean fauna hotspot in the Robe Valley of the Pilbara region, Western Australia. This fauna was collected from up to 50 m below ground level using mining exploration drill holes and monitoring wells. Altogether, 123 subterranean species were collected over a distance of 17 km, comprising 65 troglofauna and 58 stygofauna species. Of these, 61 species were troglobionts and 48 stygobionts. The troglofauna occurs in small voids and fissures in mesas comprised mostly of an iron ore formation, while the stygofauna occurs in the alluvium of a river floodplain. The richness of the Robe Valley is not a localized aberration, but rather reflects the richness of the arid Pilbara region. While legislation in Western Australia has recognized the importance of subterranean fauna, mining is occurring in the Robe Valley hotspot with conditions of environmental approval that are designed to ensure species persistence.

scholarly journals Influence of Fluoride Concentration and pH Value of 35% Hydrogen Peroxide on the Hardness, Roughness and Morphology of Bovine Enamel

2014 ◽  
Vol 15 (4) ◽  
pp. 392-398 ◽  
Author(s):  
Wilcilene Costa Nascimento ◽  
Yasmin do Socorro Batista de Lima Gomes ◽  
Larissa Dias Alexandrino ◽  
Hilton Tulio Costi ◽  
José Otávio Carrera Silva ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Ph Value ◽  
Morphological Changes ◽  
Fluoride Concentration ◽  
Knoop Hardness ◽  
Scanning Electron Micrographs ◽  
High Concentration ◽  
Acidic Group ◽  
Bovine Enamel

ABSTRACT Aim The aim of this in vitro study was to evaluate the effects of different sodium fluoride (NaF) concentrations and pH values on the Knoop hardness (KHN), surface roughness (SR), and morphology of bovine incisors bleached with 35% hydrogen peroxide (HP). Materials and methods Sixty-five bovine incisors were fragmented (5 mm2 × 2 mm) and distributed in 5 groups: Control (unbleached), Low NaF/Acidic (35% HP + 1.3% NaF, pH 5.5), Low NaF/Neutral (35% HP + 1.3% NaF, pH 7.0), High NaF/ Acidic (35% HP + 2% NaF, pH 5.5), and High NaF/Neutral (35% HP + 2% NaF, pH 7.0). KHN analysis was performed with a microhardness tester under a load of 25 gf for 5 seconds. The average SR was obtained with a rugosimeter. KHN and SR were analyzed before and after treatments. For morphological analysis, specimens were dehydrated and gold-sputtered, and scanning electron micrographs were obtained and analyzed by 3 examiners with a double-blinded technique. KHN and SR results were analyzed by one-way ANOVA and Tukey's test (p < 0.05). Results Only the Low NaF/Acidic and Low NaF/Neutral groups showed significant differences between the initial and final KHN values. All bleached groups presented significant differences between the initial and final SR values. Among the bleached groups, the least and most morphological changes were shown by the High NaF/Neutral and the Low NaF/Acidic group, respectively. Conclusion Treatment with 35% HP and 2% NaF at pH 7.0 promoted the least changes in morphology, hardness and roughness among the bleached groups. Clinical significance In-office bleaching with high-concentration HP and 2% NaF at neutral pH promoted the least changes in enamel hardness, SR, and morphology compared to other treatments. How to cite this article Nascimento WC, Gomes YSBL, Alexandrino LD, Costi HT, Silva JOC Jr, Silva CM. Influence of Fluoride Concentration and pH Value of 35% Hydrogen Peroxide on the Hardness, Roughness and Morphology of Bovine Enamel. J Contemp Dent Pract 2014;15(4):392-398.

scholarly journals Service Life Prediction of Shaft Sidewall Exposed to Sulfate Environment

2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Wei He ◽  
Xia Meng ◽  
Ji-hui Zhao
Keyword(s):  
Life Prediction ◽  
Laboratory Tests ◽  
Residual Life ◽  
Underground Water ◽  
Corrosion Mechanism ◽  
Research Subject ◽  
High Concentration ◽  
Degradation Model ◽  
Immersion Corrosion ◽  
Different Parts

Under the influence of underground water with high concentration of sulfate, several vertical shafts in the Huang-Huai region are seriously corroded but have varying degradation degrees in different parts. Taking the auxiliary shaft of Lin-Huan coal mine as the research subject, the mechanism of this phenomenon was studied. Then, wet-dry alternated and immersion corrosion tests were carried out, and it was found that only the dry-wet alternated accelerate test is representative of the corrosion mechanism that cause the corrosion in the shaft. However, it will cost much time and money for the laboratory test to reach the same degradation depth. To solve this problem, combining with field and laboratory tests, a modified theoretical degradation model was developed to evaluate the residual life of the corroded sidewall. The results indicate that the residual life of the shaft sidewall is 25 years, and the damaged parts have no need for an immediate reinforcement.

Impact of Reducing Water Fluoride on Dental Caries and Fluorosis

2020 ◽  
pp. 002203452097877
Author(s):  
P. James ◽  
M. Harding ◽  
T. Beecher ◽  
D. Browne ◽  
M. Cronin ◽  
...  
Keyword(s):  
Primary Teeth ◽  
Fluoride Concentration ◽  
Permanent Teeth ◽  
Caries Experience ◽  
Caries Prevalence ◽  
Fluoride Toothpaste ◽  
Significant Difference ◽  
Policy Measures ◽  
The Difference ◽  
Water Fluoride

Guidance intended to reduce fluoride toothpaste ingestion in early childhood was introduced in Ireland in 2002. In 2007, water fluoride concentration was adjusted from 0.8–1.0 to 0.6–0.8 ppm. The objective of this study was to determine the difference in caries and fluorosis levels following introduction of these 2 policy measures. A before-and-after study compared caries and fluorosis in random samples of 8-y-olds in Dublin ( n = 707) and Cork-Kerry ( n = 1148) in 2017 with 8-y-olds in Dublin ( n = 679) and Cork-Kerry ( n = 565) in 2002. Dentinal caries experience (primary teeth, d3vcmft(cde)) and fluorosis (permanent teeth, Dean’s index of very mild or higher) were clinically measured. Lifetime exposure to community water fluoridation (CWF) was classified as “full CWF”/“no CWF.” Effect of examination year on caries prevalence and severity and fluorosis prevalence was assessed using multivariate regression adjusting for other explanatory variables. There was little change in commencement of fluoride toothpaste use at ≤24 mo following introduction of toothbrushing guidance. Among children with full CWF, there was no statistically significant difference in caries prevalence or severity between 2017 and 2002. In 2017, caries prevalence was 55% in Dublin (full CWF) and 56% in Cork-Kerry (full CWF), and mean d3vcmft(cde) among children with caries was 3.4 and 3.7, respectively. Caries severity was less in 2017 (mean 4.2) than 2002 (mean 4.9) among children with no CWF ( P = 0.039). The difference in caries severity between children with full CWF and no CWF was less in 2017 than in 2002 (interaction P = 0.013), suggesting a reduced benefit for CWF in 2017. In 2017, fluorosis prevalence was 18% in Dublin (full CWF) and 12% in Cork-Kerry (full CWF). Fluorosis was predominantly “very mild” with no statistically significant difference between 2017 and 2002. CWF at 0.6 to 0.8 ppm is an effective caries-preventive measure. Results suggested low uptake of toothbrushing guidance, a reduced caries-preventive effect for CWF in primary teeth, and no reduction in fluorosis following introduction of the policy measures.

scholarly journals Refinement of Alternate Wetting and Drying Irrigation Method for Rice Cultivation

2014 ◽  
Vol 17 (1-2) ◽  
pp. 33-37 ◽  
Author(s):  
Priya Lal Chandra Paul ◽  
MA Rashid ◽  
Mousumi Paul
Keyword(s):  
Grain Yield ◽  
Water Level ◽  
Block Design ◽  
Water Productivity ◽  
Ground Surface ◽  
Soil Surface ◽  
Ground Level ◽  
Wetting And Drying ◽  
Alternate Wetting And Drying ◽  
Below Ground

Experiments were conducted at BRRI farm Gazipur during Boro season 2010-12 to determine maximum depth of water level below ground surface in alternate wetting and drying (AWD) method. The experiment was laid out in a randomized complete block design with four irrigation treatments. The treatments of AWD method were: T1 = continuous standing water, T2 = irrigation when water level reached 15 cm below ground level, T3 = irrigation when water level reached 20 cm below ground level and T4 = irrigation when water level reached 50 cm below ground level. The experiment involved BRRI dhan28 as a test crop. The treatment T2 gave the highest grain yield (5.9 and 6.2 ton/ha) in 2010-11 and 2011-12, respectively. Maximum benefits per hectare were found Tk. 5476 and 4931 for using 807 and 880 mm water during 2010-11 and 2011-12 respectively and thus water productivity was 7.1 kg/ha-mm in T2 for both the seasons. Continuous standing (T1) water (1013 and 1100 mm) gave comparable grain yield 5.7 and 6.0 ton/ha in 2010-11 and 2011-12, respectively. Minimum water productivity was found in treatment T1 (5.6 and 5.4 kg/ha-mm) for both the seasons. Application of irrigation when water was 15 cm below soil surface was found most profitable in AWD system and the grain yield was decreased when water level was below 15 cm depth. Therefore, the recommended AWD technology could increase rice yield and save irrigation water by 25-30 percent.DOI: http://dx.doi.org/10.3329/brj.v17i1-2.20899Bangladesh Rice j. 2013, 17(1&2): 33-37

Dental Fluorosis: Concentration of Fluoride in Drinking Water and Consumption of Bottled Beverages in School Children

2014 ◽  
Vol 38 (4) ◽  
pp. 338-344 ◽  
Author(s):  
N Pérez-Pérez ◽  
N Torres-Mendoza ◽  
A Borges-Yéñez ◽  
ME Irigoyen-Camacho
Keyword(s):  
School Children ◽  
Dental Fluorosis ◽  
Tap Water ◽  
Soft Drink ◽  
Economic Status ◽  
Fluoride Concentration ◽  
Soft Drink Consumption ◽  
Socio Economic Status ◽  
Study Results ◽  
Water Fluoride

Objective: The purpose of the study was to identify dental fluorosis prevalence and to analyze its association with tap water fluoride concentration and beverage consumption in school children from the city of Oaxaca, who were receiving fluoridated salt. Study design: A cross-sectional study was performed on elementary public school children. Dean's Index was applied to assess dental fluorosis. The parents of the children who were studied completed a questionnaire about socio-demographic characteristics and type of beverages consumed by their children. A total of 917 school children participated in this study. Results: Dental fluorosis prevalence was 80.8%. The most frequent fluorosis category was very mild (41.0%), and 16.4% of the children were in the mild category. The mean water fluoride concentration was 0.43 ppm (±0.12). No association was detected between tap water fluoride concentration and fluorosis severity. The multinomial regression model showed an association among the mild fluorosis category and age (OR = 1.25, [95%CI 1.04, 1.50]) and better socio-economic status (OR = 1.78, [95%CI 1.21, 2.60]), controlling for fluoride concentration in water. Moderate and severe fluorosis were associated with soft drink consumption (OR = 2.26, [95%IC 1.01, 5.09]), controlling for age, socio-economic status, and water fluoride concentration. Conclusions: The prevalence of fluorosis was high. Mild fluorosis was associated with higher socio-economic status, while higher fluorosis severity was associated with soft drink consumption.

scholarly journals A MULTI-BASELINE 12 GHz ATMOSPHERIC PHASE INTERFEROMETER WITH ONE MICRON PATH LENGTH SENSITIVITY

2012 ◽  
Vol 01 (01) ◽  
pp. 1250002 ◽  
Author(s):  
ROBERT S. KIMBERK ◽  
TODD R. HUNTER ◽  
PATRICK S. LEIKER ◽  
RAYMOND BLUNDELL ◽  
GEORGE U. NYSTROM ◽  
...  
Keyword(s):  
Path Length ◽  
Statistical Data ◽  
Ground Level ◽  
Low Noise ◽  
System Stability ◽  
Primary Data ◽  
Below Ground ◽  
Satellite Dish ◽  
Analog Correlator ◽  
Target Satellite

We have constructed a five station 12 GHz atmospheric phase interferometer (API) for the Submillimeter Array (SMA) located near the summit of Mauna Kea, Hawaii. Operating at the base of unoccupied SMA antenna pads, each station employs a commercial low noise mixing block coupled to a 0.7 m off-axis satellite dish which receives a broadband, white noise-like signal from a geostationary satellite. The signals are processed by an analog correlator to produce the phase delays between all pairs of stations with projected baselines ranging from 33–261 m. Each baseline's amplitude and phase is measured continuously at a rate of 8 kHz, processed, averaged and output at 10 Hz. Further signal processing and data reduction is accomplished with a Linux computer, including the removal of the diurnal motion of the target satellite. The placement of the stations below ground level with an environmental shield combined with the use of low temperature coefficient, buried fiber optic cables provides excellent system stability. The sensitivity in terms of rms path length is 1.3 microns which corresponds to phase deviations of about 1° of phase at the highest operating frequency of the SMA. The two primary data products are: (1) standard deviations of observed phase over various time scales, and (2) phase structure functions. These real-time statistical data measured by the API in the direction of the satellite provide an estimate of the phase front distortion experienced by the concurrent SMA astronomical observations. The API data also play an important role, along with the local opacity measurements and weather predictions, in helping to plan the scheduling of science observations on the telescope.

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