Top PDF Measurement of radon-222 and radium-226 in well water of Kelantan

Measurement of radon-222 and radium-226 in well water of Kelantan

Measurement of radon-222 and radium-226 in well water of Kelantan

Agensi Perlindungan Persekitaran atau Environmental Protection Agency (EPA) dari Amerika Syarikat menetapkan aras pencemaran maksimum atau Maximum Contamination Level (MCL) untuk 222 Rn di dalam air minuman adalah 11.1000 Bq/l dan untuk 226 Ra adalah 0.1100 Bq/l. Kajian ini dijalankan untuk mengenalpasti aras 222 Rn dan 226 Ra dalam air perigi persendirian di negeri Kelantan. Sebanyak 25 sampel air perigi telah dikumpul dari pelbagai daerah di negeri tersebut. Aras 222 Rn dan 226 Ra terlarut dalam air perigi diukur dengan menggunakan teknik
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Measurement of radon-222 and radium-226 in well water of Kelantan

Measurement of radon-222 and radium-226 in well water of Kelantan

11.1000 Bq/l dan untuk 226Ra adalah 0.1100 Bq/l. Kajian ini dijalankan untuk mengenalpasti aras 222Rn dan 226Ra dalam air perigi persendirian di negeri Kelantan. Sebanyak 25 sampel air perigi telah dikumpul dari pelbagai daerah di negeri tersebut. Aras 222Rn dan 226Ra terlarut dalam air perigi diukur dengan menggunakan teknik pembilang sintilator. Kepekatan aktiviti bagi 222Rn adalah dalam julat 0.0491 sehingga 4.3127 Bq/l untuk sampel tidak dituras dan dituras. Sementara itu, aktiviti bagi 226Ra, kepekatan yang diukur adalah antara 0.0278 sehingga 1.9670 Bq/l untuk kedua-dua sampel yang tidak dituras dan dituras, iaitu melebihi nilai MCL. Dari sampel, boleh anggar dos tahunan yang berkesan untuk pengambilan radionuklid semulajadi dalam air perigi bagi tiga kumpulan umur yang berbeza telah dianggarkan berdasarkan jumlah air yang digunakan. Purata pengambilan dos tahunan berkesan bagi 226Ra yang dikira untuk bayi adalah dalam lingkungan 0.12 sehingga 1.79 ^Sv/y. Bagi kanak-kanak pula, purata dos tahunan berkesan adalah dalam lingkungan 0.11 sehingga 0.34 ^Sv/y. Manakala purata pengambilan dos tahunan berkesan untuk orang dewasa dalam lingkungan 0.11 sehingga 0.33 ^Sv/y. Pengambilan dos tahunan berkesan untuk bayi didapati lebih tinggi daripada kumpulan lain tetapi masih berada dalam had seperti yang disyorkan oleh World Health Organization (WHO). Dos untuk kedua-dua kumpulan yang lain adalah di
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Simple analysis of radioactivity, and assessment of radiological  hazards in different types of household foods

Simple analysis of radioactivity, and assessment of radiological hazards in different types of household foods

From point of view measurements of radon and radium concentrations in foods are main for the health safety. Radium- 226 in the environment is broadly spreading, and usually presented in several concentrations in soils, water, foods, sediments and rocks. However, the chemical manner of radium is as like as calcium, therefore radium absorbed to blood from lungs or GI-tract or follows the manner of calcium and is mainly deposited in bone (Abdalsattar et al., 2015). Radon-222 is a progeny product of radium-226which is called alpha gas emitter. Its half-life of 3.82 days with alpha energy 5.49Mev. Radon progenies are Po-218 and Po-214 emit alphaparticles. These daughters yields are hard and have a trend to relate themselves to aerosols in around air. When human respire or inhale radon and its progenies along with the normal air, most of the radon is exhaled, its progenies become record to the internal walls and membranes of our respiratory system and continue producing steady damage because of theiralpha activity (Shoeib, and Thabayneh., 2014).
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ASSESSMENT OF GROUNDWATER RADON CONCENTRATIONS IN KELANTAN, MALAYSIA

ASSESSMENT OF GROUNDWATER RADON CONCENTRATIONS IN KELANTAN, MALAYSIA

daughter product 222 Rn is emanated and diffused into pore volume between soil and/or rock grains. Radon may remain in the material or find its way and be released to ambient air or migrated into groundwater. Groundwater that is in contact with radium-containing rock and soil will be a receptor of radon emanating from the surroundings. Radon may also be taken up by water as it passes over rocks and through the soil. The amount of radon dissolved in groundwater depends on a few factors such as aquifer characteristics, the water residence time in the aquifer, radium content in rock, etc. In groundwater, radon may be transported over some distances by diffusion and also by the mechanical flow of the water. Due to its relatively low solubility in water, radon is prone to degassing from water in contact with air. But due to its short half-life (3.8 days), much of radon will decay before reaching the water surface.
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Divergent drivers of carbon dioxide and methane dynamics in an agricultural coastal floodplain: post-flood hydrological and biological drivers

Divergent drivers of carbon dioxide and methane dynamics in an agricultural coastal floodplain: post-flood hydrological and biological drivers

following the sediment equilibration technique described in Corbett et al. (1998). Briefly, 1 kg sediment samples were obtained from two soil layers below the surface up to 1 m depth. Samples were only taken from this depth as shallow groundwater is the major interacting groundwater source with the surface water due to the presence of a 10 m thick layer of gel- like marine/estuarine clay that exists >1.5 m from the surface. This deeper sediment has a very low hydraulic conductivity (White et al., 2003), and acts as a confining layer between any deeper groundwater aquifers. Known volumes of radium-free tap water equilibrated with the atmosphere was added to the sediments and incubated for 21 days to allow for radon source ( 226 Ra decay) and sink ( 222 Rn decay) to reach steady state equilibrium. The radon concentration in the water was then measured on a RAD7 using procedures described above. The radon concentrations from each sediment incubation were averaged to provide an integrative groundwater radon endmember. This technique is a widely used approach for estimating the radon endmember in groundwater discharge studies (Burnett et al., 2007; Peterson et al 2008; Schmidt et al., 2010).
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Studies on Uranium And Radon Concentration In Bore Well Water of Kodagu District, India

Studies on Uranium And Radon Concentration In Bore Well Water of Kodagu District, India

Radioactivity is ubiquitous in nature. Natural uranium and its daughter products such as radium and radon are present in natural soil and water at different levels of concentrations [1]. Uranium and radon will contribute a significant component of the radiation exposure to the population. When ground water moves through soil and rocks, radioactive elements get dissolved due to leaching from minerals and transported with the water. Intake of radionuclides above the maximum contaminant level causes health effects and these radionuclides in the environment will contribute radiological risk to the population. Uranium is the heaviest trace element, has widespread occurrence in nature and decays into several short-lived and long-lived radioisotopes including radium and radon. The concentration of uranium generally varies from 0.5 to 5ppm in natural soil and rocks [2]. The average concentration of uranium in the earth crust is 0.0003%. Natural uranium is a mixture of three isotopes 238 U (99.29%), 235 U (0.72%) and 234 U (0.0054%) [2,3]. The study of uranium in ground water is essential for the hydro geochemical prospecting of uranium and for the assessment of health risks to the public due to consumption of water [4]. 222 Rn is a chemically inert, colourless, odourless and radioactive noble gas with a half-life of 3.82 days. It is a daughter product of 226 Ra in uranium decay series. Radon is readily soluble in water and its mole fraction solubility in water is 2.3×10 -4 at 15°C and 0.00125 at 37°C and its solubility decreases with temperature and increases with pressure. Radon gas can dissolve in groundwater and released into the indoor air during household activities as bathing, dish and cloth washing. Exposure to waterborne radon may occur by ingestion and inhalation. When inhaled over prolonged periods it is capable of causing lung cancer [1, 5]. A study on dissolved radionuclides in gives the key aspect for evaluation and control of natural exposure [6,7]. Therefore, radiological monitoring of water quality is an important parameter of environmental studies.
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Properties of Matrix using TiO2photocatalyst for Improving Air Quality

Properties of Matrix using TiO2photocatalyst for Improving Air Quality

As the test method of this study, the compressive strength was tested in accordance with KS L ISO 679, and the size of the matrix was measured to be 40 * 40 * 160 (mm). For the thermal conductivity, the test matrix was made with 50 * 50 * 50 (mm) according to KS L 9016, and the thermal conductivities at 7 and 28 days were measured. The measurement of the concentration of radon and the measurement of the fine dust concentration were carried out using the measurement method of indoor harmful substance concentration at Hanbat National University in Korea. Test is carried out after putting harmful substances, adsorption type matirx, concentration measuring instrument, fan, etc. in a chamber made of SUS material. The test matirx of the radon gas and fine dust concentration test shall be tested in the size of 40 * 160 * 160 (mm). The concentration stabilization period in the chamber is set to about 3 days and measurement is started like [Figure 5]. The measurement period can be classified into short term and long term, and the test factors of the longevity and fine dust concentration are somewhat similar.[9][10]
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Radon exhalation from phosphogypsum stabilized in sulfur polymer cement

Radon exhalation from phosphogypsum stabilized in sulfur polymer cement

Most sedimentary phosphate rock deposits contain ele- vated levels of radionuclides from 238 U in secular equi- librium with its daughters [5]. Chemical processing of the phosphate rock in order to produce phosphoric acid, re- sults in a fractionation into the acids and PG of radio- element contained in phosphate rock [6]. The phospho- gypsum contains specific activities of 226 Ra, the decay chain

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Concentration And Effective Dose Of Radon 222 In The Genow Hot Spring; Bandar Abbas City, Iran

Concentration And Effective Dose Of Radon 222 In The Genow Hot Spring; Bandar Abbas City, Iran

Rn is inserted into the lungs, where it began to decay. With the release of alpha radiation during decay, DNA lung cells are damaged and the cancer cells are finally formed [ 11 ] . The studies have shown that consuming water containing high concentration of P

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Radium/Radon Content and Radon Exhalation Rates from Some Soil Samples by Using SSNTD

Radium/Radon Content and Radon Exhalation Rates from Some Soil Samples by Using SSNTD

mechanisms influencing indoor radon levels in many buildings [2]. It was reported that a world wide average of 60.4% of indoor radon comes from the ground and surrounding soil of buildings [3]. Information on the spatial variability of radon exhalation rate would be useful for identifying areas with a risk of high radon exposure. On the other hand, the well understood chemical behavior (inert gas) of radon 222 Rn and its convenient half life

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Predicting the Occurrence of Radon-222 in North Carolina Groundwater

Predicting the Occurrence of Radon-222 in North Carolina Groundwater

Joint significance test for discharge, specific capacity, casing length, uncased length, controlling for rock type and geologic region. Significance test for rock type, controlling for[r]

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Potential applications of rapid microbiological methods for detection of  antibiotic residues in wastewater, surface and well water

Potential applications of rapid microbiological methods for detection of antibiotic residues in wastewater, surface and well water

The spiked samples were prepared with defined concentrations of an- tibiotics. Standard solutions of antibiotics benzyl penicillin, ampicil- lin, cloxacillin, erythromycin, kanamycin, nalidixic acid and chloram- phenicol, were prepared in concentrations, which are minimal detection limits for used methods for milk. To study the matrix effect, we prepared samples of water and milk with the same concentrations of dissolved antibiotics. Each antibiotic was dissolved in sterile dis- tilled water in different concentrations. For the preparation of milk samples, the antibiotics were first dissolved in distilled water as stock solutions and then in reconstituted skim milk (Skim milk powder, 1.15363, Merck, Germany) as well. The proportion of the added aqueous standard solution in the final milk dilution step was less than 1 %. The selection of concentrations for the determination of the senstivity for each test was based on the detection limits men- tioned by producers, together with at least one concentration step higher and two concentration steps lower [18] (Table 1). The spiked samples were divided into three subsamples and frozen at -20 °C ± 2 °C. The test kits with different batches were used for detecting the antibiotics in each subsample.
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Evaluation of Dug-Well as a Safe Water Alternative Option in Case of Arsenic Contamination in Groundwater

Evaluation of Dug-Well as a Safe Water Alternative Option in Case of Arsenic Contamination in Groundwater

In Simple Bleaching Treatment method, in a small bucket, the desired amount of bleaching powder is mixed well with water to prepare a homogeneous concentrated solution. After filtration the bucket containing the solution is placed into the dug-well water with a rope. The bucket is shaken well so that bleaching powder is mixed with water slowly. After few minutes the remaining solution in the bucket is poured into the water. It was found that if the bleaching powder (e.g., LOBA, India) contained 32% of chlorine, then the amounts of bleaching powder required for 3-6, >6-10 and >10 ft depth of water were 0.10, 0.15 and 0.25 kg respectively. It is to be noted that the dug-well water should not pump out or use before 24 hours of disinfection.
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Increased radon 222 in soil gas because of cumulative seismicity at active faults

Increased radon 222 in soil gas because of cumulative seismicity at active faults

and the ground surface, respectively; p(g) is almost con- stant (=1 atm) despite small fluctuations with weather con- ditions, and p(s) is variable. It is reasonable to consider that the Δσ can enhance p(s). This enhancement induces an in- crease in v and consequently an increase in 222 Rn concen- tration because of the sensitivity of the concentration to v. At active fault areas with many recent earthquakes (e.g., IM, HN, and AR), p(s) is considered to be at a higher level than in inactive seismic areas because of frequent ground motions that enhance strain and stress. Additionally, the motions may have generated preferred pathways in shallow soils for the carrier gas, such as cracks and connections between pores. This pathway generation can also en- hance v and cause a nonequilibrium condition of soil gas. These states essentially enhance 222 Rn concentra- tion without the accumulation of 226 Ra.
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Identifying persistent temperature inversion events in a subalpine basin using radon-222

Identifying persistent temperature inversion events in a subalpine basin using radon-222

Atmospheric radon measurements were made for 1 year (14 December 2016 to 30 November 2017) at the Ljubljana Bežigrad (LjB) automatic weather station in the central part of the city (46 ◦ 07 0 N, 14 ◦ 52 0 E; Fig. 1c), and are ongoing. The measurements were conducted using an AlphaGUARD PQ2000 PRO (Bertin Instruments) ionization chamber oper- ating in diffusion mode with a 1 h integration time. The in- strument was mounted 1.5 m above ground level (m a.g.l.), within a Stevenson Screen instrument shelter. Setup in this way more than 95 % of the observed radon concentrations represent the isotope 222 Rn (Kochowska et al., 2009). Con- sequently, to a good approximation contributions from the isotopes 220 Rn (thoron) and 219 Rn (actinon) can be ignored. The AlphaGUARD has a lower limit of detection (LLD) of around 2 Bq m −3 . Over the year only 1 % of observed radon concentrations were at or below this limit, which justifies the continued use of the AlphaGUARD at this site as a tool for air quality assessment.
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Measurement and Improvement of Service Qualit...

Measurement and Improvement of Service Qualit...

As of late, preparing has progressed toward becoming as an interest in person since it is viewed as the principle pathway to frame sufficient HR in term of value and amount. Subsequently, it goes for giving people data and regulatory, specialized abilities required to complete their work in productivity and adequacy. A short time later, this will decidedly impact association work and its execution. Preparing is one of the key change measures to arrange hotel. Along these lines, it is clear why extensive offer are deducted from spending plan and committed to preparing process in hotels. To get accomplishments in the preparation procedure, the idea of preparing ought to be clear for all joined gatherings (coaches, learners and preparing authorities) because of its solid impact on well-planning and usage of preparing programs and on current systems that satisfy the requirements of staff and improve their insight and abilities also. In addition, receiving the aggregate quality frameworks in preparing specifically will overhaul the level of hotel administrations.
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Radiological assessment of exposure doses and radon exhalation rates of building materials in Saudi Arabia

Radiological assessment of exposure doses and radon exhalation rates of building materials in Saudi Arabia

The external exposure dose to people is due to naturally occurring isotopes, which vary based on the surrounding geological nature and geographical altitude conditions in the region in which people live. Granite is the more favorable natural material that contains uranium. However, it usually is possible to ind bedrocks rich in uranium or different types used in the domestic market as building materials. Building materials are sources of aerosol radioactivity. In addition, external radiation also occurs as a result of the decay series of uranium in buildings. However, radon inlet into houses is a complicated process involving building materials, soil, gas, water, and weather-related parameters, where 226 Ra in construction materials in some cases are the primary
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Measuring radon 222 in soil gas with high spatial and temporal resolution

Measuring radon 222 in soil gas with high spatial and temporal resolution

Radon-222 activity concentrations in field samples of soil gas 60 cm depth measured on seven different days between September and December 2013 using two detection methods: liquid scinti[r]

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Physical Factors Affecting the Interior Radon Concentrations

Physical Factors Affecting the Interior Radon Concentrations

Researchers have realized that radon-contaminated air inside buildings is a principal way of human exposure to certain healthy-risks. A model is developed to estimate radon concentrations which consider various parameters: in indoor air radon (radon-222) concentration, air permeability of ground, air pressure difference between outdoor and indoor at ground level, ventilation of building ground and number of air changes per hour due to ventilation. The radon-222 transport into building might dominated by diffusion, pressure driven flow or/and a mixture of both depending on the actual values of the various parameters. So, in several and regular periods of time: January, April, July and October, radon-222 concentrations have been measured in ten rooms of five elementary schools and in five rooms of one high school at Qena city (Upper Egypt). This has been carried out using alpha scintillation counters. We have noticed that in three rooms the value has exceeded 200 Bq·m −3 at the basement and only one room at the first floor, and all values have changed with respect to time and localization: They have decreased from July to January and from basement to first floor. For example, radon-222 concentrations obtained by exposing track detectors varied in the range from 20 Bq·m −3
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