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MAMON SARKAR, AKASH, JANNATUN NAYEEM, M. MOSTAFIZUR RAHAMAN, and M. SARWAR JAHAN. "DISSOLVING PULP FROM NON-WOOD PLANTS BY PREHYDROLYSISPOTASSIUM HYDROXIDE PROCESS." Cellulose Chemistry and Technology 55, no. 1-2 (2021): 117–24. http://dx.doi.org/10.35812/cellulosechemtechnol.2021.55.12.
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The garment industry is the backbone of Bangladesh’s economy, which imports 30000 metric tons of rayon fiber every year. Bangladesh used to have a rayon plant, but it was shut down a long time ago. At present, the establishment of a new rayon plant in Bangladesh has become an objective. As a forest deficient country, non-wood plants need to be explored for rayon grade dissolving pulp production. Therefore, in this paper, prehydrolysis potassium hydroxide (KOH) pulping process has been investigated for dissolving pulp production from rice and wheat straws, corn stalk, dhaincha and jute stick. The lowest prehydrolysis yield was 70.1% obtained for corn stalks and the highest prehydrolysis yield was 92.1% for wheat straw. The KOH cooking of prehydrolysed rice straw, wheat straw and corn stalks with 14% alkali charge produced pulps with kappa numbers of 5.7, 4.5 and 8.8, respectively, while prehydrolysed dhaincha and jute stick needed 18% alkali charge to get a bleachable pulp. Dhaincha showed the highest pulp yield (37.3%) with the highest α-cellulose content (92.24%) and the lowest residual pentosan content (5.37%). Further purification with cold KOH extraction increased purity by 3% for rice straw pulp and by 1% for dhaincha, wheat straw, corn stalks and jute stick pulp. Thus, the dissolving pulp produced in this study by the prehydrolysis KOH process can meet the criteria for rayon grade pulp.
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Perrier, Antoine. "Les arthroses du premier rayon, prise en charge par orthèse plantaire pré- et postchirurgicale." Revue du Podologue 12, no. 70 (2016): 11–15. http://dx.doi.org/10.1016/j.revpod.2016.06.004.
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Cauchie2, Jean-François, Patrice Corriveau, Bryan Hamel, and Annie Lyonnais. "Un droit criminel en retrait ou en introspection ?" Criminologie 51, no. 2 (2018): 13–38. http://dx.doi.org/10.7202/1054233ar.
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En 1892, date de la création du premier Code criminel canadien, la tentative de suicide est un crime, et ce, jusqu’à sa décriminalisation en 1972. Du droit criminel à la psychiatrie, le déplacement de la réaction sociale à la tentative suicidaire aurait en quelque sorte été « officialisé » par ce retrait de l’article de loi. Nous verrons néanmoins dans le présent article qu’il n’y a pas eu, pour les tentatives de suicide, d’abord prise en charge pénale et seulement ensuite, encadrement médical. En effet, au tournant du 20e siècle, le droit criminel cohabite déjà depuis un moment avec cet autre régime de vérité qu’est la psychiatrie. L’analyse de 163 plaintes pour tentatives de suicide à Montréal entre 1908 et 1919 montre qu’il faut être prudent avant de diagnostiquer qu’un type de régulation prend la place d’un autre. En effet, un verdict d’aliénation mentale ou une prise en charge médicale sans procès d’un individu aux tendances suicidaires ne sortent pas de facto le dossier judiciaire du rayon d’action du droit criminel. Il serait davantage question d’une réorganisation, voire d’un renouvellement partiel de ce type de droit quant aux options qu’il mobilise pour traiter des plaintes relatives aux tentatives de suicide.
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Dasweptia, Dasweptia, Agung Satria Hamdani, and Tommy Kurniawan. "Pengaruh Penempatan Lightning Arrester Sebelum Dan Sesudah Fuse Cut Out Terhadap Tegangan Lebih Pada Transformator Distribusi 20 Kv Di PT. PLN (Persero) Rayon Tanjung Karang." Jurnal Ilmiah Teknik Elektro 4, no. 1 (2022): 18–22. http://dx.doi.org/10.36269/jtr.v4i1.988.
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Lightning strikes on airborne transmission networks such as in distribution lines are injections of electric charge. The injection of the charge will cause a voltage increase in the network, so that more tension will arise in the network. Lightning Arrester (LA) is one of the equipment in the protection system to protect the 20 kV distribution transformer against overvoltage coming from lightning strikes. Under normal circumstances LA acts as an insulator, but when exposed to lightning strikes LA will function as a conductor whose resistance is relatively low, so that it can flow the surge current to the ground. This study aims to see the effect of the placement of lightning arresters before and after fuse cut out on overvoltage in the 20 KV distribution transformer, so that which placement is better is obtained, taking into account factors that affect the level of voltage and overcurrent that occurs in each system such as the location of LA placement, the steepness of incoming waves, the speed of propagation of surja waves, the voltage is large through the protection system, and the Basic Insulation Level (BIL) value of the equipment. So that in the end, the right PLACEMENT of LA was obtained as a 20 kv distribution transformer protection. Based on the results of the study, the voltage that reached the transformer was 67,192 kV, in this condition the transformer was still in a safe state because the voltage hitting the transformer was smaller than the transformer's BIL, which was 67.192kV<125 kV. the installation of the arrester after Fuse Cut Out is better because the voltage hitting the transformer is smaller than the installation of the arrester before Fuse Cut Out with a voltage difference of 69,092 kV - 67,192 kV = 1.9 kV.
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Torrego Serrano, Florencia. "El transporte de mercancías por carretera en España según la III encuesta nacional." Estudios Geográficos 51, no. 198 (1990): 115–37. http://dx.doi.org/10.3989/egeogr.1990.i198.115.
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Utilizando la información que nos proporciona la III encuesta nacional sobre transporte de mercancías por carretera, analizamos algunos aspectos de la misma. Estudiamos, en primer lugar, la distribución de mercancías a nivel interregional, señalando las áreas de abastecimiento más destacadas de cada región, así como el movimiento intra y extrarregional de las mismas. Los vehículos/kilómetro los analizamos según su radio de acción (nacional, comarcal o local), los intervalos de distancia y la capacidad de carga. Destacamos las toneladas de mercancías transportadas que sitúan a la carretera en el primer lugar del total de medios utilizados y, por último, tenemos en cuenta las Tm/Km. según el tipo de mercancías, ya sean éstas alimentos, materias primas, productos energéticos, manufacturados y otros.
 
 [fr] Utilisant l’information que nous procurons la III enquête national sur transport de marchandise dans la route, nous analysons quelques aspestes de la meme. Nous étudions dans premier lieu la distribution de marchandise à l'échelon intèrrégional, signalant les zones de approvisionnent ent plus détachés de chaque région, comme ci le mouvement intra et extrarrégional de les mêmes. Les véhicules/Km. nous les analysons selon son rayon d'action (national, régional, local), les intervalles de distance et la capacité de charge. Nous détachons les tonnes de marchandises transportés, lesquels situent á la route dans le premier lieu du total de moyens utilisés et finalment les Tm/Km. selon le genere de marchandise, nourritures, matières primes, produits énergétiques, manufacturés et autres.
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Zona, Mega Asri. "Pengaruh Kepemimpinan Transformasional Pada Sinisisme terhadap Perubahan Organisasional dengan Keadilan Distributif sebagai Pemoderasi." Managament Insight: Jurnal Ilmiah Manajemen 9, no. 1 (2014): 1–15. http://dx.doi.org/10.33369/insight.9.1.1-15.
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This research used transformational leadership as independent variables which had negative influence on cynicism about organizational change. While distributive justice used as moderated variable that expected to affect the relationship of transformational leadership on cynicism about organizational change. The survey was conducted to 250 employees of PT PLN branch Padang (Rayon Kuranji, Rayon Tabing, Rayon Belanti and Rayon Indarung), PT Telkom area Padang, PT MNC Sky Vision (KPP KPP Padang and Bukittinggi). At least, 202 Questionnaires were collected, but only 187 questionnaires that can be processed.
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Ahmat, Salhadine Yacoub, Kebalo Sosso Piham, Teko Dede Virginie, et al. "Traumatisme Ouvert de la Main par Introduction dans le Moulin (main de moulin) Chez l’Enfant : Aspects Epidémiologiques, Lésionnels, et Thérapeutiques au Service de Chirurgie Pédiatrique du Centre Hospitalier Universitaire Sylvanus Olympio de Lomé (Togo)." European Scientific Journal, ESJ 19, no. 36 (2023): 40. http://dx.doi.org/10.19044/esj.2023.v19n36p40.
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Contexte : la main de moulin se définit comme tout traumatisme de la main causée par une machine servant à moudre des céréales, des légumes ou toute autre denrée alimentaire. Elle est rencontrée dans notre milieu hospitalier motivant notre étude. Objectif : étudier les aspects épidémiologiques, lésionnels et donner un aperçu sur la prise en charge de la main de moulin au service de chirurgie pédiatrique du CHU Sylvanus Olympio de Lomé.
 Méthodes : il s’agissait d’une étude rétro prospective couvrant une période de 5 ans allant du 01 juin 2017 au 31 Mai 2022. Ont été inclus tous les enfants de 0 à 15 ans pris en charge dans le service de chirurgie pédiatrique du CHU SO Lomé pour un traumatisme ouvert de la main causé par un moulin.
 Résultats : nous avons enregistré 30 cas des mains de moulin soit 5,23% de tous les traumatismes ouverts de la main. La prédominance était masculine (18 garçons contre 12 filles). La tranche d’âge la plus touchée était celle de 10 à 15 ans avec un âge moyen de 9,07 +/- 4. La circonstance la plus retouvée était l’accident de travail. La majorité des traumatismes ont eu lieu au moulin public. La face de la main la plus touchée était celle plantaire. Le troisième rayon était le plus touché. Sur la face palmaire, la zone I de Verdan était la plus touchée dans 16 cas ainsi que sur la face dorsale dans 4 cas. Les phalanges étaient les plus touchées. La fracture était la lésion la plus fréquente. Les gestes opératoires etaient multiples du fait de la multiplicité des lésions.
 Conclusion : les mains de moulin chez l’enfant sont caractérisées par des lésions multiples et variées rendant la prise en charge complexe, posant ainsi un problème de santé publique.
 
 Context: mill hand is defined as any trauma to the hand caused by a machine used to grind cereals, vegetables or any other foodstuff. It is encountered in our hospital environment motivating our study.
 Objective : étudier les aspects épidémiologiques, lésionnels et donner un aperçu sur la prise en charge de la main de moulin au service de chirurgie pédiatrique du CHU Sylvanus Olympio de Lomé.
 Methods: this was a retro prospective study covering a 5-year period from June 01, 2017 to May 31, 2022. Were included all children aged 0 to 15 years cared for in the pediatric surgery department of CHU SO Lomé for open hand trauma caused by a mill.
 Results: We recorded 30 cases of mill hands, i.e. 5.23% of all open hand traumas. The predominance was male (18 boys versus 12 girls). The age group most affected was 10 to 15 years, with an average age of 9.07 +/- 4. The most common circumstance was a work accident. The majority of injuries occurred at the public mill. The side of the hand most affected was the plantar side. The third ray was the most affected. On the palmar side, Verdan zone I was most affected in 16 cases, and on the dorsal side in 4 cases. The phalanges were the most affected. Fracture was the most frequent lesion. Multiple surgical procedures were required, due to the multiplicity of lesions.
 Conclusion: Mill hands in children are characterized by multiple and varied lesions, making management complex and posing a public health problem.
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Park, Young-Ho, and Hyock Jun Son. "EBIS charge breeder for a heavy ion accelerator RAON." Vacuum Magazine 5, no. 3 (2018): 21–26. http://dx.doi.org/10.5757/vacmac.5.3.21.
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Gubanski, Adam, Jan Kupracz, Paweł Kostyla, Dominika Kaczorowska, and Jerzy Wrobel. "Application of the Electret in Alpha Radiation Sensor to Measure the Concentration of Radon in Selected Ambient Conditions." Journal of Sensors 2019 (November 11, 2019): 1–9. http://dx.doi.org/10.1155/2019/1705481.
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A novel electret sensor, made from a polytetrafluoroethylene (PTFE) foil, is proposed for monitoring of radon concentration in closed spaces. A triode air system was implemented to form the electret foil. In order to calibrate the electret sensor, the ionization chamber with the electret embedded at its bottom, was placed in an emanation chamber containing radon of known concentration. The change in the effective charge density of the electret resulting from the interaction of the electret sensor with ionizing radiation, make it possible to determine the degree of its response to the radon concentration in the examined environment. The electric charge of the electret sensor was evaluated at the beginning and at the end of the concentration measurement using a field chopper. The measurement of the value of the electric field between the electret and the reference electrode directly corresponds to the effective surface charge density of the electret. The measuring system was calibrated in values of the electret equivalent voltage of Uz. In order to assess the electret properties, both the thermostimulated charge relaxation (TSQ) method and the thermostimulated discharge current (TSDC) method were used to evaluate corresponding parameters. These investigations led to the optimization of the electret formation process for the maximum sensitivity to the effects of alpha particles resulting from radon radioactive decay.
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Yutsis, Vsevolod, Anatolyi Kotsarenko, Vladimir Grimalsky, and Sergey Pulinets. "On the Radon-Related Mechanism of the Seismo- and Volcanogenic Geomagnetic Anomalies: Experiments in Tlamacas Mountain (Volcano Popocatepetl Area) and Electrode Effect Model." Atmosphere 14, no. 4 (2023): 705. http://dx.doi.org/10.3390/atmos14040705.
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The noise-like behavior of the geomagnetic anomalies observed in Tlamacas station (volcano Popocatepetl, Mexico), linked to the ionization produced by intensive radon release, are presented in the experimental part of this study. The magnetic field perturbations produced by charge spreading currents within the fair-weather electric field are considered in the theoretical model based on the electrode. The electric charges are generated by the air ionization due to radon emanation. The simulations demonstrated that the ionization of the air leads to magnetic field perturbations of about 0.001–0.1 nT in the ULF (ultra low frequency) range 10−3–10−1 Hz. Magnetic field perturbations can be higher when the radon emanation occurs in a region with terrain irregularities.
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Röttger, Stefan, Annette Röttger, Claudia Grossi, et al. "Radon metrology for use in climate change observation and radiation protection at the environmental level." Advances in Geosciences 57 (March 10, 2022): 37–47. http://dx.doi.org/10.5194/adgeo-57-37-2022.
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Abstract. Radon (222Rn) gas is the largest source of public exposure to naturally occurring radioactivity and the identification of radon priority areas is required by the Council Directive 2013/59/Euratom. Radon is also used as a tracer to improve atmospheric transport models and to indirectly estimate greenhouse gas (GHG) fluxes using the Radon Tracer Method (RTM). This method is based on the correlation between atmospheric concentrations of radon and GHG, together with information on the radon flux data. For radiological data, all European countries have installed networks of automatic gamma dose rate monitoring stations and report the real-time information gathered to the European Radiological Data Exchange Platform (EURDEP). So far, atmospheric radon activity concentrations and radon fluxes are not yet reported in EURDEP, nor routinely measured within the European radiological networks although these observations could help to avoid false positives results. Due to above applications, there is a need of building a metrological chain to ensure high quality radon activity concentrations and radon flux measurements. Both climate and radiation protection research communities underline the need for improved traceability in low-level atmospheric radon measurements (Khanbabaee et al., 2021). The EMPIR project 19ENV01 traceRadon1 is aimed towards providing the necessary measurement infrastructure and transfer standards to fulfil this need. Results of this project are particularly important for improving independent GHG emission estimates that support national reporting under the Paris Agreement on climate change and for the Council Directive 2013/59/Euratom, thus benefitting two large scientific communities. In this paper, early results, such as new activity standard developments and an overview of commercial and research radon monitors are presented and discussed. These results will feed into the traceRadon project with respect to radionuclide metrology in air and its potential for the improvement of the RTM.
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Andreev, A., E. Atanova, I. Teslenko, and M. Cycareva. "Researches of Radon Field Formation Indoors (through the Example of Far Eastern State Transport University)." Safety in Technosphere 8, no. 1 (2020): 3–10. http://dx.doi.org/10.12737/1998-071x-2019-3-10.
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Full-scale investigations have demonstrated that radon contained in soil air provides dominant influence on the university’s radon field formation. The change of radon volume activity in the university’s civil defense hideout and premises have strongly pronounced seasonal pattern with maximum values of radon concentration in July and August, and minimum values in March, April and November. Radon escaping from the soil surface in the summertime does not affect the radon field change in the university’s premises. The most precise estimation of radon annual average volume activity can be obtained when performing observations during a year. The substitution of this approach by the method of measurements with various duration leads to errors in the estimation of the normative parameter because of difficulties in registration of radon variations in various conditions.
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Chen, B., C. Zhao, D. Fan, and W. Zhuo. "INFLUENCE OF STATIC ELECTRICITY ON RADON MEASUREMENT USING PASSIVE DETECTORS." Radiation Protection Dosimetry 184, no. 3-4 (2019): 444–47. http://dx.doi.org/10.1093/rpd/ncz067.
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Abstract In order to investigate the influence of the static electricity on the measurement using passive radon detector, detectors were charged at the surface of chamber and its CR-39 elements respectively on purpose before the exposure in this study. The results of in-chamber experiments revealed that the static electricity would lead to critical influence on measurement especially when the CR-39 elements were negatively charged. The static charge would remain for several ten hours, which result in more significant influence on the short-term measurement.
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Wang, Hong, Wenhua Wang, Runcheng He, et al. "Experimental Study on Unsteady Radon Exhalation from the Overburden Layer of the Uranium Mill Tailings Pond under Rainfall." Science and Technology of Nuclear Installations 2022 (September 19, 2022): 1–8. http://dx.doi.org/10.1155/2022/9366056.
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In order to find out radon reduction performance of the overburden layer on uranium mill tailings (UMTs) pond beach surface after rainfall, the rainfall simulation experiment of the overburden layer was carried out with the self-developed equipment. Based on the radon migration model of the overburden layer on the UMTs pond beach surface, the change rule of radon exhalation in four types of compactness of the overburden layer within 120 hours after rainfall was studied, and the corresponding moisture content was also analyzed. The results show that the radon concentration in the overburden layer of UMTs increases nonlinearly; the dynamic change in moisture content of the overburden layer on the beach surface leads to the unsteady radon exhalation. The variation of radon exhalation shows three stages: increase, linear decrease, and stability tendency. After rainfall, radon exhalation rate increases due to water vapor and there is free radon seepage in pores. With the decrease of free radon production rate, radon exhalation rate gradually decreases until it reaches stability again. When the thickness of the overburden layer reduces, the porosity decreases with the increase in compactness of the overburden layer. While the decrease in radon reduction is more obvious, the less time it takes for radon exhalation to vary from unstable to stable overburden after rainfall.
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Imaaduddiin, Muhammad Hafiizh, Ismail Saud, and Rahmad Putra Santoso. "Recommendations for planning water infrastructure in the Surabaya City area with the influence of watershed characteristics to realize sustainable settlement drainage that is safe from flooding." IOP Conference Series: Earth and Environmental Science 1095, no. 1 (2022): 012033. http://dx.doi.org/10.1088/1755-1315/1095/1/012033.
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Abstract The development of urban areas often has an impact on changes in the surface run off area of water flow, a consequence that often occurs is flooding due to an increase in the value of run off drainage from housing/industries which burdens the capacity of urban land drainage channels. The analysis carried out is to calculate the value of the travel time (Tc) from the build area compared to the peak time (Tp) in the urban partial drainage flow. The value of time concentration is influenced by the slope of topography and watershed area of each rayon in Surabaya. The calculated Tc and Tp values will be combined to find the linear correlation value of the effect of watershed characteristics on development/change of land area in Surabaya. The results of the linear analysis of the relationship between the area of the build up area and the combined travel time in each rayon are not the same, this is due to the influence of land topographic slopes in each rayon and also the area of the watershed be different. the length of the channel on the drainage of urban area in each rayon have a separate drainage network sub system from one another. This is a consideration that the determination of the formulation of the relationship between the area of the build up area and the time and volume of the reservoir must adjust the characteristics of each rayon.
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Marlow (INVITED), W. H. "Electrical Charge in Radon Daughter Deposition: A Critical Review." Radiation Protection Dosimetry 24, no. 1-4 (1988): 211–15. http://dx.doi.org/10.1093/oxfordjournals.rpd.a080272.
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Abstract The roles that electric charges play in the various deposition processes of radon daughter atoms has been a matter of conjecture for many years. In this review, several possible effects of charge are described. The sources of cluster ions in indoor air and their attachment to aerosol particles are then considered. Since the 'background' aerosol is central to the questions of deposition, its physical behaviour is discussed in the context of charge attachment and other properties. Data from experiments on decay product neutralisation during the first few seconds after birth, room air interactions from several different types of experiments, and deposition following inhalation are then reviewed. The interpretation of these experiments is given and directions for research needed better to identify critical issues are isolated.
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Lomas, P. R., and B. M. R. Green. "Temporal Variations of Radon Levels in Dwellings." Radiation Protection Dosimetry 56, no. 1-4 (1994): 323–25. http://dx.doi.org/10.1093/oxfordjournals.rpd.a082480.
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Abstract Several factors determine the concentration of radon in a dwelling: the uranium content and permeability of the building ground; the construction and integrity of the floor; the habits and preferences of the occupants. Whereas the geological factors are unlikely to alter over time, it is quite possible for structural changes to occur, such as settlement cracking, which increases radon ingress, and for the occupants to change their living habits, such as increasing ventilation, which may reduce radon levels. New occupants may arrive with entirely different lifestyles. Questions arise about the variability of indoor radon levels as time progresses and as occupants change. The database of radon results for UK homes, which extends backwards for about a decade, is examined for repeat measurements, and the data are analysed so as to assess the stability or otherwise of the levels under changing circumstances.
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Neugebauer, Thomas, Hans Hingmann, Jonas Buermeyer, Volker Grimm, and Joachim Breckow. "Radon emission rate and analysis of its influencing parameters." Nukleonika 61, no. 3 (2016): 337–42. http://dx.doi.org/10.1515/nuka-2016-0056.
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Abstract The geological and structural conditions define the radon situation inside a building. While the geological realities can be specified by the content of radium-226 and the ratio of radon-222 emitted from the ground the structural conditions are defined by the tightness of the building envelope. The radon concentration inside has an unsteady character, which is caused by meteorological conditions outside and the air change rate (ACH or ACR), which in turn is influenced by the residents’ behaviour such as venting and heating. For the assessment of the radon exposition, it is necessary to perform measurements for a long time. An approach to reduce this time by eliminating the inhabitants influence on the radon concentration is the radon emission rate, also known as radon entry rate. This variable is based on the measurement of the radon concentration and the parallel determination of the air change rate via a tracer gas method, the result expresses a released activity per time. Due to their noisy character, it is necessary to apply a smoothing algorithm to the input parameters. In addition to mean values, the use of window functions, known from digital signal processing, was analysed. For the verification of the whole calculation procedure, simulations and measurements under defined conditions were used. Furthermore, measurements in an uninhabited house showed proof of the capability of the assessment of the radon potential. First examinations of influencing parameters of the radon emission rate showed a possible dependence on the temperature difference inside and outside the building.
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Othman, Sardar Q., Sarbaz I. Mohammed, and Ali H. Ahmed. "ANTIOXIDANTS, BIOCHEMICAL, AND HEMATOLOGICAL PARAMETERS CHANGE IN WORKERS OCCUPATIONALLY EXPOSED TO RADON INHALATION AT CERTAIN CONSTRUCTION MATERIAL INDUSTRIES IN ERBIL, IRAQ." Science Journal of University of Zakho 12, no. 1 (2024): 57–69. http://dx.doi.org/10.25271/sjuoz.2024.12.1.1221.
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This study examined the effects of radon on the endogenous antioxidants, biochemical, and hematological parameters of workers in Erbil, Iraqi Kurdistan. This was carried out to ascertain how radon affects the health of those who work in certain factories producing building materials. The case study group consisted of 70 workers, who were then divided into seven subgroups (gypsum, cement plant, lightweight block, marble, red brick 1, crushed stone, and concrete block 2), while the control group consisted of 20 healthy volunteers. The total antioxidant capacity (TAC), levels of carcinoembryonic antigen (CEA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX), the complete blood count (CBC), and liver function tests were evaluated. The statistical analysis revealed that the antioxidant activities and CEA levels between the case study group and the control group differed significantly. Also, antioxidant enzyme activities and indoor radon concentration, the annual effective dosage, were found to be highly significantly correlated by Pearson and Spearman analyses in the case study group. Additionally, the results demonstrated a substantial correlation in the data between the levels of CEA biomarkers and radon (r=0.478, p˂0.000). The present results showed that radon concentration increased alanine aminotransferase (ALT) activity in a radon concentration-dependent manner (r=0.263 and p ˂0.05). The aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin activities, on the other hand, were not significantly affected by radon. The most significantly influenced CBC parameter was the low white blood cells (WBC) in the case study group compared to the controls. Low platelet count (PLT) was the second-highest problematic metric. The other CBC values, however, did not significantly differ between the research group and the control group. This study offers a preliminary image of the endogenous antioxidant systems in employees, especially to show a connection between radon and the occurrence of cancer among workers in Iraq Kurdistan Region.
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Diouf, Abdoulaye, Nicolas Barbier, Ali Mahamane, Jean Lejoly, Mahamane Saadou, and Jan Bogaert. "Caractérisation de la structure spatiale des individus ligneux dans une « brousse tachetée » au sud-ouest du Niger." Canadian Journal of Forest Research 40, no. 4 (2010): 827–35. http://dx.doi.org/10.1139/x10-031.
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La structure spatiale des végétations périodiques en zones arides est liée, selon des modèles d’auto-organisation, à des processus locaux (facilitation ou compétition). La présente étude visait à vérifier l’importance de ces processus et le rôle du Combretum micranthum G. Don à travers une description de la distribution spatiale des ligneux d’une brousse tachetée au sud-ouest du Niger à l’aide de la fonction K de Ripley. L’organisation spatiale des ligneux révèle une structure à deux échelles : (i) agrégative (rayon moyen, 9–15 m) et (ii) répulsive (vers 35 m), correspondant au patron périodique d’ensemble. Seul le C. micranthum présente une distribution similaire, suggérant un rôle d’espèce « clé de voûte », déterminant la structure d’ensemble. Une agrégation locale d’espèces secondaires autour du C. micranthum suggère fortement une facilitation de portée (1–3 m) proportionnelle au rayon moyen du houppier des arbustes matures, conformément aux prédictions des modèles et aux études empiriques de la dynamique hydrique du sol. L’absence de relation spatiale entre le C. micranthum et les autres espèces de la famille des Combretaceae formant entre elles des agrégats suggère l’existence d’une structure à trois composantes. Ces éléments permettront d’aiguiller les démarches empiriques et d’améliorer les modèles, lesquels s’avèrent indispensables pour la gestion des végétations sahéliennes face aux contraintes d’aridité et d’exploitation.
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Peng, Xiao Yong, Zhen Hao Liu, Qing Fang Xie, Xin Zhang, Fen Wan, and Shuai Huang. "Numerical Simulation of Atmospheric Diffusion of Radon Emanating From Flat Ground Uranium Tailings Impoundment in Different Heights." Advanced Materials Research 518-523 (May 2012): 1677–81. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.1677.
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The atmospheric diffusion and concentration distribution of radon (emanation rate is 6.06 Bq/m2s ) emanating from the flat ground uranium tailings impoundment at various heights(0m, 10m, 20m, and 30m) are simulated. The numerical results show that the different height of the tailings impoundment will mainly influence the radon concentration that could change in the range of 16~250 Bq/m3 at the downwind region of 0-300m. The radon concentration and annual effective doses for public from radon decrease sharply with the increasing distance away from tailings impoundment, are higher than that of the decommissioned uranium tailings impoundment (its height is 30m, radon emanation rate is 0.74 Bq/m2s ). The annual effective doses for public from radon are highly up to 1.12 mSv/a, and are 0.12 mSv/a greater than the national standard in the range of 800m. Considering the difference of average radon emanation rate and other factors, the protective distance from radon should be adjusted appropriately.
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Agafonova, N. Yu, E. A. Dobrynina, and N. A. Filimonova. "Measurement of radon decays with the LVD-setup for neutrino searching." Seriya 3: Fizika, Astronomiya, no. 1_2023 (June 2, 2023): 2310202–1. http://dx.doi.org/10.55959/msu0579-9392.78.2310202.
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The LVD (Large Volume Detector), located at the Low Background Laboratory, Gran Sasso, Italy, is built to detect neutrinos from stellar core collapses in our Galaxy. The peculiarity of the search for rare events requires close attention to the background of the experiment, such as the natural radioactivity of the rock and detector materials and the interaction of cosmic ray muons underground. The LVD is capable of detecting gamma quanta from the decay of radon daughter nuclei. We convincingly show the connection between the change in the background counting rate from gammas in the detector and the change in the concentration of radon nuclei in the experimental hall. We also point out the existence of another source of radon change, this is seismic activity.
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R. Stanifer, Stacy, and Ellen J. Hahn. "Analysis of Radon Awareness and Disclosure Policy in Kentucky: Applying Kingdon’s Multiple Streams Framework." Policy, Politics, & Nursing Practice 21, no. 3 (2020): 132–39. http://dx.doi.org/10.1177/1527154420923728.
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The purpose of this article is to analyze radon awareness and disclosure policy proposed during the 2018 Kentucky General Assembly using Kingdon’s Multiple Stream Framework. Radon gas is the second leading cause of lung cancer. Exposure to radon occurs largely in the home. The proportion of homeowners who have completed radon testing remains low, and home radon testing is voluntary in most states. The Environmental Law Institute recommends states enact policies to promote radon awareness and testing. The most common radon awareness policy mandates radon disclosure during a real estate transaction. A bill to mandate radon disclosure during a real estate transaction was proposed during the 2018 Kentucky General Assembly but was met with opposition and was not filed. As a policy alternative, an administrative regulation to amend the Form for Seller’s Disclosure of Conditions was proposed to the Kentucky Real Estate Commission. Administrative regulations set forth by government regulatory agencies are equally enforceable and may be a more politically feasible alternative to enacting public policy. Nurses are positioned to promote the health of patients and populations. Nurses advocating for radon control legislation and/or administrative regulations may push radon control policy higher on the governmental decision agenda leading to policy change to decrease the development of lung cancer.
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Komeijani, A., H. Bagheri, and B. Shekarchi. "Surface potential uniformity and sensitivity of large-area PTFE electret discs of different thicknesses produced by a modified corona poling rotating system for dosimetry applications." Journal of Advanced Dielectrics 09, no. 06 (2019): 1950050. http://dx.doi.org/10.1142/s2010135x19500504.
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In this study, large-area (6-cm diameter) Teflon polytetrafluoroethylene (PTFE) discs of different thicknesses (0.2-, 0.5- and 1 -mm) were negatively and positively charged by using the “modified single point-to-plane corona poling rotating system”. The effects of some crucial parameters of the PTFE disc as well as the modified corona poling rotating system on the PTFE surface potential uniformity such as: (a) PTFE disc thickness, (b) PTFE disc polarity and (c) needle-to-PTFE disc distance were successfully reported. Accordingly, closer needle-to-PTFE disc distance, positive charging mode and thinner PTFE disc provided a better PTFE surface potential uniformity. However, the effects of PTFE charge polarity and needle distance on the electrostatic charge potential uniformity were much more remarkable in comparison with the effects of PTFE thickness. Additionally, the surface potential distribution profiles of charged PTFE discs were totally flat and independent of the PTFE thickness at 5- and 13-[Formula: see text]mm needle distances for the negative and positive charging modes, respectively. At the optimized charging conditions, large-area PTFE electret disc (0.5-mm-thick) with positive uniform surface charge potential especially at the edges up to [Formula: see text] 1.8[Formula: see text]kV with stability up to 77 days studied was produced by applying a new multiple heat treatment protocol to the PTFE disc for radon dosimetry. As also observed in this study, the sensitivity of PTFE electret dosimeters to a defined radon gas concentration increases as the PTFE thickness increases. Meanwhile, 0.5-mm-thick PTFE electret disc produced was selected to be used as a high quality electret dosimeter with acceptable and superior parameters for different applications in particular medium-term radiation dosimetry in both low and high dose rate ionizing radiation fields.
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Mrdja, Dusan, Istvan Bikit, Miroslav Veskovic, et al. "A simple model for the assessment of indoor radionuclide Pb-210 surface contamination due to the presence of radon." Nuclear Technology and Radiation Protection 28, no. 1 (2013): 68–72. http://dx.doi.org/10.2298/ntrp1301068m.
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The presented, very simplified model provides a possibility for estimation of surface Pb-210 activity, depending on the changes of Rn-222 concentration during the long-term radon presence inside the closed room. This can be useful for retrospective assessment of the average indoor radon concentration for certain historical period, based on the surface contamination by the radionuclide Pb-210 in a closed or poorly ventilated room over a long period of time. However, the surface Pb-210 contamination depends on the pattern of radon concentration changes, and in this model is supposed that the change of indoor radon concentration, which periodically enters the room, is affected only by the radioactive decay and the inserted amount of radon in each entry. So, each radon entry can be comprehended as a ?net amount? of radon, or excess which remains inside the room due to radon?s periodical in-out flow. It is shown, that under the conditions of the model, the achieved average value of radon concentration of 275 Bq/m3, implies that the saturated surface contamination by the Pb-210 of 160 Bq/m2 after approximately 150 years.
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Μητρόπουλος, Π., K. Notsu, Ν. Δελήμπασης, N. Κακαβάς, and Π. Βουδούρης. "EARTHQUAKE PREDICTION IN THE AREA OF N. EVIA ON THE BASIS OF GROUNDWATER RADON CONCENTRATION CHANGES." Bulletin of the Geological Society of Greece 36, no. 3 (2004): 1356. http://dx.doi.org/10.12681/bgsg.16488.
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Significant changes in the groundwater radon concentration, were observed on the 29/7/2003, at Kammena Vourla. The radon concentration changes can be attributed to the temporary enrichment of the groundwater by radon from the surrounding rocks due to the action of stress release or stress accumulation prior an earthquake. EPPO was immediately informed for the existence of these changes. On the 3/8/2003, a significant number of earthquakes in Northern Evia were recorded in an interval of a few hours. The epicentres of the earthquakes were located in the conceivable line between the epicentre of the strong earthquake of Skyros island (July 2001) and the site of the station of radon measurement at Kammena Vourla, on the extension of the Northern Aegean fault. In the 23/1/2003, in the same station, 3 significant changes of radon concentration were measured EPPO was immediately informed for impending seismic activity in Northern Evia. On the 29th of January three earthquakes were recorded. Their epicentres were located in N. Evia, close to the radon measurement, station. On the 2/2/2003, a new significant radon change occurred at Kammena Vourla followed by an earthquake (7/2/2003). In the 12/2/2003 in a letter that we addressed to the EPPO administration, the beginning of a new radon change was reported which also led to an earthquake with the same epicentre. The changes that are recorded in the system of radon measurement of Kammena Vourla are precursors of earthquakes, related to the extension of the N. Aegean fault towards the Sterea Hellas and have their epicentre in N. Evia. It seems that the method can be an important tool for local, short term earthquake prediction.
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Outkin, V. I., I. A. Kozlova, A. K. Yurkov, P. K. Dutta, O. P. Mishra, and M. K. Naskar. "Radon monitoring as a possible indicator of tectonic events." Earth System Dynamics Discussions 4, no. 1 (2013): 93–107. http://dx.doi.org/10.5194/esdd-4-93-2013.
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Abstract. The proposed work describes research into the behavior of radon (VAR-volume activity of radon) excreted from the array. Radon migration and its selection from the array depends on the porosity, permeability and fractures in the array. A drastic change in the strength of an array and reset the elastic stresses by external forces (earthquake) occurs when certain changes in the structure of the array as the compressive and tensile strength of the array.
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Sinha, S. K., and R. Chattopadhyay. "A STUDY ON SPINNING LIMITS AND YARN PROPERTIES WITH PROGRESSIVE CHANGE IN YARN COUNT IN FRICTION SPINNING." AUTEX Research Journal 7, no. 1 (2007): 1–8. http://dx.doi.org/10.1515/aut-2007-070101.
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Abstract The spinning limit for three different fibres (cotton, viscose rayon and polyester) on a Dref-3 friction spinning machine has been investigated. The change in yarn properties with progressive change in count has also been reported. The count range has been seen to be dependent on fibre type. As one progresses from very coarse to fine counts, the yarn tensile property remain fairly unaltered for cotton, but changes for polyester and viscose yarns.
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Dobrovolný, T., M. Jiránek, and J. Krejsová. "THE INFLUENCE OF PINHOLES IN WATERPROOFING MATERIALS ON THE VALUE OF THE RADON DIFFUSION COEFFICIENT." Radiation Protection Dosimetry 191, no. 2 (2020): 238–43. http://dx.doi.org/10.1093/rpd/ncaa160.
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Abstract This article focuses on an experimental study of the influence of imperfections on the value of the radon diffusion coefficient of various waterproofing materials. Microscopic holes were made by a thin tip or by a microdrill bit to imitate the real damage that can be incurred during construction. To determine the change in the radon diffusion coefficient, each waterproofing material was measured five times. The first measurement was performed on undamaged samples, while the following measurements were performed on samples with one, two, four and eight pinholes. The radon diffusion coefficient was measured under nonstationary conditions, because homemade radon sources with a slow rate of radon emanation were used. The radon diffusion coefficients identified in the study were compared according to the thickness of the material and the number and the size of the pinholes. The exact shape and size of the imperfections were documented by an electron microscope.
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Dai, Xingwang, Yifan Chen, Yan Chen, et al. "Effect of Thickness and Compaction Degree of Overburden Soil on Radon Reduction for Uranium Tailings Reservoir." Science and Technology of Nuclear Installations 2021 (March 20, 2021): 1–8. http://dx.doi.org/10.1155/2021/9984939.
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The thickness and compaction degree of the overburden soil on the beach of the uranium tailings reservoir has an important influence on the radon reduction rate. A theoretical model of radon exhalation is established and an experimental device is designed. The main results are as follows. (1) The radon reduction rate increases with the increase of thickness. When the soil compaction degree is 85.5%, 90.2%, and 94.8%, the radon reduction efficiency increases significantly when the thickness increases from 5 cm to 10 cm, and when the soil thickness is over 10 cm, the increase of radon reduction efficiency tends to be stable. When the compaction degree is 80.9%, the radon reduction rate always increases obviously with the increase of the thickness of the overburden soil, but the increase rate shows a downward trend. (2) The radon reduction rate increases gradually with the increase of compaction degree, and the increasing trend becomes less obvious when the compaction degree is more than 85.5%. Besides, the effect of the change of soil compaction on radon reduction rate decreases with the increase of soil thickness. The calculation formulas about the effect of thickness and compaction degree on radon reduction rate can guide the design and construction of radiation protection of uranium tailings reservoir.
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Hariyanto, Dedi, and Subhan A. "Faktor-Faktor Yang Mempengaruhi Pelanggan Menunggak Rekening Listrik Pada PLN Sub-Rayon Sentebang." JURNAL MANAJEMEN MOTIVASI 11, no. 1 (2016): 585. http://dx.doi.org/10.29406/jmm.v11i1.62.
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This research is using survey. Populations used are all customers of PT. PLN (Persero) Sub Rayon Sentebang ever in arrears to pay the electricity bill, with a sample of 100 people who use techniques Probability Sampling type of stratified sampling proportional sample criteria in this study are customers aged> 20 years, whether married or not married and customer ever dives at least 2 months delinquent. This study using factor analysis. The results showed that the Factors Affecting Customer DelinquentElectricity Account In. PLN (Persero) Sub Rayon Sentebang is the payment process is complicated, quality distribution of electricity that is not good, quality of service disruption poor, low income customers, Deliberate customers delay payments, attitude PLN officers unfavorable, fee late charges are low, the payment system is not good, often delay the payment of electricity bills and lack of good quality KWH meter PLN.
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Xie, Yan Shi, Kai Xuan Tan, Liang Chen, Kai Guang Hu, Zheng Qing Wang, and Xiu Cai Wang. "Fractal Analysis of Spatial Distribution of Radon Exhalation Rates of Uranium Mill Tailings." Advanced Materials Research 524-527 (May 2012): 584–87. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.584.
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A uranium mill tailings, located in Guangdong, was selected for spatial distribution of the radon exhalation rates measured by local static method. The two-dimension surface of radon exhalation rates was established by Surfer using the data of spatial distribution of radon exhalation rates measured at August 14, 2007 to 19 and 21, which was analyzed by fractal method of projective covering. The results show that the two-dimension surface of radon exhalation rates is of fractal structure. The fractal dimension of surface of radon exhalation rates from August 14, 2007 to 19 and 21 are 2.0535, 2.0173, 2.0029, 2.0084, 2.0079, 2.0057 and 2.0034, respectively, which indicates that the complexity of spatial distribution of the radon exhalation rates at 14 and 15 are larger than that of the other days. The phenomenon results from the change of precipitation and temperature, as well as the features of uranium mill tailings, including mineral composition, particle size, radium content, porosity and pore connectivity, etc.
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Deng, Han, Minzhi Long, Gang Tian, et al. "Detection of radon based on the lead-induced conformational change in aptamer T30695." RSC Advances 6, no. 43 (2016): 37254–57. http://dx.doi.org/10.1039/c6ra03481k.
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Fromreide, M., and I. Henne. "Smart control of HVAC based on measurements of indoor radon concentration." TOS Forum 2022, no. 11 (2022): 441. http://dx.doi.org/10.1255/tosf.172.
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Sufficient ventilation is important for creating a healthy indoor environment in both households and larger buildings (schools, offices, shops, warehouses). As the cost of heating and ventilation in large buildings is very large, modern ventilation systems apply smart control for optimizing the energy consumption. The control is typically based on temperature and/or CO2 levels, whereas other pollutants such as particulate microparticles and radon are not accounted for. Exposure to indoor radon is the second most important reason for lung cancer, with more than 200 000 casesestimated worldwide every year. The indoor radon concentration depends on many factors, from local geological conditions and weather, to building materials and natural and mechanical ventilation. Together with the Norwegian company OBEO AS, NORCE has completed a study of the indoor radon concentration at a Norwegian primary school prone to high radon levels. The study includes continuous measurements of radon, CO2 and temperature for multiple rooms for different use as well as data for the ventilation system. The aim for the project was to build knowledge for a larger research project, where the goal is to develop a control algorithm for HVAC systems which also takes radon levels into account. An important challenge is to make accurate sensors for measuring radon continuously at an affordable price for implementation in complex buildings. Generally, sensors that can measure at high frequency with good accuracy is very expensive. Thus, developing algorithms and mathematical models to treat the data from low-cost sensors can be an adequate tool for large systems/buildings. One must also account for the positioning of the sensor. For instance, it is known that the radon concentration is better distributed in a room with mechanical ventilation than in a room without, making the position of the sensor important for better interpretation of measurement data. In the pre-project we have studied how the radon levels show large variations that are related to the ventilation operation and daily/weekly variations. The large variations show the need for a high sampling rate (minutes to hours) to capture the peaks in the concentration. We have also studied the rate of change in radon concentrations over time and have amongst discovered a noticeable delay from the start of ventilation until radon is effectively removed from the air. The rate of change is an important parameter for planning ahead and securing fresh air during the full period of presence whilst optimizing the energy cost.
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Smetanová, Iveta, Karol Holý, Ľubica Luhová, Kristian Csicsay, Dagmar Haviarová, and Lucia Kunáková. "Seasonal variation of radon and CO2 in the Važecká Cave, Slovakia." Nukleonika 65, no. 2 (2020): 153–57. http://dx.doi.org/10.2478/nuka-2020-0025.
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AbstractThe continuous monitoring of 222Rn activity concentration, CO2 concentration, and microclimatologic parameters (internal air temperature and relative humidity) in the Važecká Cave (Northern Slovakia) is being carried out at three monitoring stations, namely, Gallery, Lake Hall, and Entrance Hall. Radon activity concentration and CO2 concentration exhibited a clear annual variation. The daily average of radon concentration ranged 1300–27 700 Bq/m3 at the Lake Hall station and 3600–42 200 Bq/m3 at the Gallery station. Radon reached its maximum in the summer months, from June to September. The annual maximum of CO2 concentration is registered approximately one month later than radon maximum. The annual variation of radon and CO2 is controlled by the seasonal change of ventilation regime associated with the seasonal variation of the difference between the temperature measured inside the cave and the atmospheric temperature.
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Huntington-Moskos, Luz, Mary Kay Rayens, Amanda T. Wiggins, Karen M. Butler, and Ellen J. Hahn. "Use of Theory-Driven Report Back to Promote Lung Cancer Risk Reduction." International Journal of Environmental Research and Public Health 18, no. 20 (2021): 10648. http://dx.doi.org/10.3390/ijerph182010648.
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Report back is active sharing of research findings with participants to prompt behavior change. Research on theory-driven report back for environmental risk reduction is limited. The study aim is to evaluate the impact of a stage-tailored report back process with participants who had high home radon and/or air nicotine levels. An observational one-group pre-post design was used, with data collection at 3, 9, and 15 months post intervention. Participants from the parent study (N = 515) were randomized to the treatment or control group and this sample included all 87 treatment participants who: (1) had elevated radon and/or air nicotine at baseline; and (2) received stage-tailored report back of their values. Short-term test kits measured radon; passive airborne nicotine samplers assessed secondhand smoke (SHS) exposure. Stage of action was categorized as: (1) ‘Unaware’, (2) ‘Unengaged’, (3) ‘Deciding’, (4) ‘Action’, and (5) ‘Maintenance’. Interventions were provided for free, such as in-person radon and SHS test kits and a brief telephonic problem-solving consultation. Stage of action for radon mitigation and smoke-free policy increased from baseline to 3 months and remained stable between 3 and 9 months. Stage of action for radon was higher at 15 months than baseline. Among those with high baseline radon, observed radon decreased by 15 months (p < 0.001). Tailored report back of contaminant values reduced radon exposure and changed the health behavior necessary to remediate radon and SHS exposure.
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Vukotic, Perko, Ranko Zekic, Nevenka Antovic, and Tomislav Andjelic. "Radon concentrations in multi-story buildings in Montenegro." Nuclear Technology and Radiation Protection 34, no. 2 (2019): 165–74. http://dx.doi.org/10.2298/ntrp181108020v.
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Change of radon concentrations in dwellings with floor level was studied in six multi-story buildings, in four towns of Montenegro with different climate conditions. The annual aver- age radon activity concentrations in 35 dwellings are found to be very low, mostly at a level of 20-30 Bqm?3. Absorbed gamma dose rates in these dwellings are in the range of 14-58 nGyh?1. The low radon concentrations are a consequence of a good tightness of the structures in contact with the ground and a small contribution of building materials to radon indoors. A clear general trend of changes in radon concentrations with floor level is not observed. In most of the dwellings on different floors in the multi-story building radon concentration varies very little, mostly within measurement error. A small decrease in radon concentration is noted between the two or three floors closest to the ground, but only in some of the buildings. Therefore, a decrease of indoor radon concentration with floor level cannot be considered as a general characteristic of multi-story buildings. Although the seasonal radon variations have not been in the focus of this study, it was found that the average radon activity concentrations in dwellings of the multi-story buildings are higher in warmer than in cooler half-year period, what is contrary to the general rule for homes in the world and in Montenegro as well.
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Marlow (INVITED), W. H. "Electrical Charge in Radon Daughter Deposition: A Critical Review." Radiation Protection Dosimetry 24, no. 1-4 (1988): 211–15. http://dx.doi.org/10.1093/rpd/24.1-4.211.
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Jeong, Jinhee, and Kyungjoo Cho. "Experimental Study on CO2 and Radon Mitigations in an Apartment Using a Mechanical Ventilation System." Buildings 13, no. 6 (2023): 1439. http://dx.doi.org/10.3390/buildings13061439.
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The public interest in indoor air quality has rapidly increased in Korean society, and ventilation systems can play an essential role in improving indoor air quality. This study aims to estimate the reduction in indoor CO2 and radon, which can be effectively mitigated by air exchange, according to the operation of mechanical ventilation in an apartment with the national standard housing size (85 m2) and shape in Korea. The time required to meet Korea’s mandatory indoor CO2 standard (1000 ppm) was 167, 98, 66, and 51 min under air change rates of 0.5, 1.0, 1.5, and 2.0 ACH (air change per hour), respectively. Regarding indoor radon, the removal rate increased with increased ventilation volume, and the minimum concentration level was low and sustained for a prolonged duration. Nonetheless, an air change rate of 0.5 ACH may not offer sufficient ventilation. Additionally, it is imperative to note that indoor radon concentrations tend to escalate swiftly when a mechanical ventilation system is deactivated. Thus, to enhance indoor air quality, it is necessary to reconsider strategies to augment the air change rate and guarantee uninterrupted ventilation.
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Su, Xiaoyun, Xiaopeng Yang, Ting Song, Wencai Wang, and Lijun Chen. "Radon concentration anomaly characteristics in the North–South seismic belt before strong earthquake." E3S Web of Conferences 261 (2021): 04029. http://dx.doi.org/10.1051/e3sconf/202126104029.
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Seismic underground fluids play an important role in earthquake prediction studies and tracking. Nearly 30 years of radon concentration monitoring data at 42 observation sites in the North–South seismic belt (22°-35° N, 100°-110° E) were collected from the National Earthquake Data Center of China Earthquake Networks Center. The possible precursor anomalies of observed radon concentration in the belt before several strong earthquakes were investigated and their spatial distribution, evolution, and variation characteristics were analyzed. The results showed that radon concentration precursor anomalies before several strong earthquakes were high, and the morphological characteristics are relatively complex. The anomaly mainly shows the turning point or accelerating change of trend background change; longer anomaly durations tend to be concentrated around epicenters. The number of observation points with anomalies was positively correlated with the proximity to the epicenter; the measurement points closest to the epicenter exhibited earlier trend anomalies. The research has important practical significance and scientific value for understanding the relationship between radon concentration anomaly and strong earthquake.
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Deng, Ming Hui, Qing Shuang Zeng, and Lan Ying Zhang. "Robust Image Information Identification Algorithm Based on Time-Frequency Chirplet-Radon Transformation." Applied Mechanics and Materials 239-240 (December 2012): 950–54. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.950.
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In this paper, a robust image watermarking method in two-dimensional space/spatial-frequency distributions domain is proposed which is robust against geometric distortion. This watermarking is detected by a linear frequency change. The one-dimensional chirplet transformation and radon transformation are used to detect the watermark. The chirp signals are used as watermarks and this type of signals is resistant to all stationary filtering methods and exhibits geometrical symmetry. In the two-dimensional Radon-Wigner transformation domain, the chirp signals used as watermarks change only its position in space/spatial-frequency distribution, after applying linear geometrical attack, such as scale rotation and cropping. But the two-dimensional Radon-Wigner transformation needs too much difficult computing. So the image is put into a series of 1D signal by choosing scalable local time windows. The watermarks are embedded in the 1D Chirplet-Radon transformation domains. The watermark thus generated is invisible and performs well in StirMark test. Compared with other watermarking algorithms, this algorithm is more robust, especially against geometric distortion, while having excellent frequency properties.
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Kaddoori, Farah Faris, Basim Khalaf Rejah, and Wijdan Thamer Fzaa. "Measuring the Pollution Level with Uranium and Radon in the Soil of Some Areas Inside Baghdad University Campus-AL-Jadiriyah." NeuroQuantology 19, no. 7 (2021): 72–77. http://dx.doi.org/10.14704/nq.2021.19.7.nq21086.
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In present study, the technique was used, including nuclear track detector type (CR-39), for appreciative concentrations uranium and radon in soil samples from Baghdad University Campus-AL-Jadiriyah utilizing a prolonged -term with a solid-state nuclear path sensor, a technique for charged particles has been developed., the radon concentrations, effective dose rate and uranium concentrations have measured in soil samples. Eight various venues from soil Baghdad University Campus have appointed. The results indicated variant values about uranium and radon concentrations, the average value for radon gas, effective dose rate and uranium concentrations was found to be 281.59 Bq/cm3, 7.09 mSv/y and 0.01 Bq/mm-2 respectively. All results appeared that concentrations for radon and uranium in soil are infra the permitted limit from (ICRP) agency which are 1100 Bq/m3 and 11.7 (mg. Kg- 1) ppm respectively. All results were comparison with the domestic and worldwide results.
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Tan, Bo, Guangyuan Yang, Shuhui Fu, and Cheng Xu. "STUDY ON RADON CONCENTRATION VARIATION DURING SUBWAY CONSTRUCTION." Radiation Protection Dosimetry 191, no. 4 (2020): 409–22. http://dx.doi.org/10.1093/rpd/ncaa168.
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Abstract The high radon concentration in the underground space of the subway station during construction often endangers the health of workers. Subway station project No. 16 in Beijing, while under construction, was selected as the main measuring point, a year’s monitoring data was obtained to analyse the change of radon concentration. It was found that the concentration of radon was basically within the range of 5 ~ 500 Bq/m3 and showing a low level in the morning and a high level at noon, and presents the seasonal rule, compared with other seasons, the summer radiation is stronger. Furthermore, among the different measuring points, the radon concentration of the heading roadway is the highest, and the construction level of the station hall is the lowest. According to the comprehensive analysis, the concentration of radon during the construction of the subway station is mainly affected by the ambient temperature and air mobility.
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Symonds, P., Z. Chalabi, G. Petrou, et al. "Exploring assumptions for air infiltration rate estimates using indoor radon in UK homes." Journal of Physics: Conference Series 2600, no. 10 (2023): 102003. http://dx.doi.org/10.1088/1742-6596/2600/10/102003.
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Abstract Radon, a known carcinogen, is one of the most commonly monitored indoor contaminants. This paper utilises findings from a previous study on indoor radon measurements in United Kingdom (UK) homes to explore the UK Government’s Standard Assessment Procedure (SAP) assumptions for air infiltration rates. These assumptions are important as they are used to assess the energy performance of dwellings and compliance with building regulations. Indoor radon data is aggregated by 16 combinations of home energy efficiency measures (loft and wall insulation, glazing upgrades and draught proofing) and fitted using a simple analytic radon model. We find indoor radon to be inversely proportional to air change rate and proportional to a fit coefficient, k, of 42.2 ± 3.1 (95% Confidence Interval (CI)). We also show that the assumptions within SAP used to estimate home infiltration rates can be modified to include the impact of home energy efficiency which improves the fit (R 2 from 0.38 to 0.51) to the radon data. This work provides evidence to help improve assumptions regarding the effects of home energy efficiency on infiltration rates.
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Kataoka, Takahiro, Hina Shuto, Shota Naoe, et al. "Radon inhalation decreases DNA damage induced by oxidative stress in mouse organs via the activation of antioxidative functions." Journal of Radiation Research 62, no. 5 (2021): 861–67. http://dx.doi.org/10.1093/jrr/rrab069.
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Abstract Radon inhalation decreases the level of lipid peroxide (LPO); this is attributed to the activation of antioxidative functions. This activation contributes to the beneficial effects of radon therapy, but there are no studies on the risks of radon therapy, such as DNA damage. We evaluated the effect of radon inhalation on DNA damage caused by oxidative stress and explored the underlying mechanisms. Mice were exposed to radon inhalation at concentrations of 2 or 20 kBq/m3 (for one, three, or 10 days). The 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels decreased in the brains of mice that inhaled 20 kBq/m3 radon for three days and in the kidneys of mice that inhaled 2 or 20 kBq/m3 radon for one, three or 10 days. The 8-OHdG levels in the small intestine decreased by approximately 20–40% (2 kBq/m3 for three days or 20 kBq/m3 for one, three or 10 days), but there were no significant differences in the 8-OHdG levels between mice that inhaled a sham treatment and those that inhaled radon. There was no significant change in the levels of 8-oxoguanine DNA glycosylase, which plays an important role in DNA repair. However, the level of Mn-superoxide dismutase (SOD) increased by 15–60% and 15–45% in the small intestine and kidney, respectively, following radon inhalation. These results suggest that Mn-SOD probably plays an important role in the inhibition of oxidative DNA damage.
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Grossi, Claudia, Daniel Rabago, Scott Chambers, et al. "Characterizing the automatic radon flux transfer standard system Autoflux: laboratory calibration and field experiments." Atmospheric Measurement Techniques 16, no. 10 (2023): 2655–72. http://dx.doi.org/10.5194/amt-16-2655-2023.
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Abstract. High-quality, long-term measurements of terrestrial trace gas emissions are important for investigations of atmospheric, geophysical and biological processes to help mitigate climate change and protect the environment and the health of citizens. High-frequency terrestrial fluxes of the radioactive noble gas 222Rn, in particular, are useful for validating radon flux maps and used to evaluate the performance of regional atmospheric models, to improve greenhouse gas emission inventories (by the radon tracer method) and to determine radon priority areas for radiation protection goals. A new automatic radon flux system (Autoflux) was developed as a transfer standard (TS) to assist with establishing a traceability chain for field-based radon flux measurements. The operational characteristics and features of the system were optimized based on a literature review of existing flux measurement systems. To characterize and calibrate Autoflux, a bespoke radon exhalation bed (EB) facility was also constructed with the intended purpose of providing a constant radon exhalation under a specific set of controlled laboratory conditions. The calibrated Autoflux was then used to transfer the derived calibration to a second continuous radon flux system under laboratory conditions; both instruments were then tested in the field and compared with modeled fluxes. This paper presents (i) a literature review of state-of-the-art radon flux systems and EB facilities; (ii) the design, characterization and calibration of a reference radon EB facility; (iii) the design, characterization and calibration of the Autoflux system; (iv) the calibration of a second radon flux system (INTE_Flux) using the EB and Autoflux, with a total uncertainty of 9 % (k = 1) for an average radon flux of ∼ 1800 mBq m−2 s−1 under controlled laboratory conditions; and (v) an example application of the calibrated TS and INTE_Flux systems for in situ radon flux measurements, which are then compared with simulated radon fluxes. Calibration of the TS under different environmental conditions and at lower reference fluxes will be the subject of a separate future investigation.
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Шитов, А. В., Д. П. Долгов, and А. А. Барсуков. "ABOUT A POSSIBLE CHANGE IN THE DYNAMICS OF VOLUMETRIC ACTIVITY OF RADON IN CONNECTION WITH THE LARGEST EARTHQUAKES (FOR EXAMPLE, MONITORING STATION VAR GORNO-ALTAYSK." Вестник КРАУНЦ. Физико-математические науки, no. 4 (December 25, 2019): 223–31. http://dx.doi.org/10.26117/2079-6641-2019-29-4-223-231.
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В работе анализируются результаты мониторинга объемной активности радона в 2015 году в связи с крупнейшими землетрясениями. Измерения производились при помощи сейсмической радоновой станции (СРС-05) в г. Горно-Алтайск. В результате изучения 11 крупнейших землетрясений выявлены основные закономерности влияния этих событий на динамику объемной активности радона. The paper analyzes the results of monitoring the volume activity of radon in 2015 in connection with the largest earthquakes. Measurements were made using seismic radon station (SRS-05) in Gorno-Altaysk. As a result of the study of 11 major earthquakes, the main regularities of the influence of these events on the dynamics of the volume activity of radon were revealed.
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Hahn, Ellen J., Luz Huntington-Moskos, Monica Mundy, et al. "A Randomized Trial to Test Personalized Environmental Report Back to Reduce Lung Cancer Risk." Health Education & Behavior 46, no. 1 (2018): 165–75. http://dx.doi.org/10.1177/1090198118788602.
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Background. More radon-related lung cancers occur among those exposed to tobacco smoke. Objectives. To test the effects of a personalized environmental report back intervention on change in stage of action for air nicotine testing and adopting a smoke-free home and radon testing and mitigation from baseline to 3 months postintervention. Methods. The study design used a two-arm parallel groups randomized controlled trial with stratified quota sampling. The treatment group received free air nicotine and radon home test kits and a brief problem-solving phone intervention; the control group received a coupon for free test kits. A sample of 515 homeowners were enrolled; 319 completed the 3-month follow-up. Stage of action to test and remediate the home was measured consistent with the precaution adoption process model. Linear mixed modeling assessed whether the main and interaction effects of treatment and time were associated with the testing and remediation outcomes; multiple covariates were included in the models. Results. The models for the four stages of action outcomes (testing and remediating for radon and secondhand smoke) each had a significant treatment-by-time effect. The general pattern was an increase in stage of action from baseline to 3 months. The degree of change was generally larger among the treatment group participants relative to the controls, indicating that those in the treatment group were more ready to take action. For all the models, participants with higher self-efficacy for radon/air nicotine testing and radon/secondhand smoke remediation were more ready to take action to test and remediate. Synergistic risk perception was associated with stage of action for radon mitigation. Conclusions. Homeowners who were provided free radon and air nicotine test kits, given their results, and engaged in a brief telephonic problem-solving consultation tended to show a greater increase in readiness to take action to test and remediate by 3 months compared with those who received standard public health practice. Both groups showed an increase in stage of action for all four outcomes over time.
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Wiebe, Daniel, Sebastian Lindemann, and Marc Schumann. "A high-sensitivity radon emanation detector system for future low-background experiments." Journal of Instrumentation 19, no. 04 (2024): P04014. http://dx.doi.org/10.1088/1748-0221/19/04/p04014.
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Abstract Radioactive radon atoms originating from the primordial 238U and 232Th decay chains are constantly emanated from the surfaces of most materials. The radon atoms and their radioactive daughter isotopes can significantly contribute to the background of low-background experiments. The 222Rn progeny 214Pb, for example, dominates the background of current liquid xenon-based direct dark matter detectors. We report on a new detector system to quantify the 222Rn surface emanation rate of materials. Using cryogenic physisorption traps, emanated radon atoms are transferred from an independent emanation vessel and concentrated within the dedicated detection vessel. The charged radon daughter isotopes are collected electrostatically on a silicon PIN photodiode to spectrometrically measure the alpha decays of 214Po and 218Po. The overall detection efficiency is ∼ 36 % for both polonium channels. The radon emanation activity of the emanation vessel was measured to be (0.16± 0.03) mBq, resulting in a detection sensitivity of ∼ 0.06 mBq at 90 % C.L.
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Weng, Xu, Weijun Luo, Yanwei Wang, Guangneng Zeng, and Shijie Wang. "Spatiotemporal Variations of Radon Concentration in the Atmosphere of Zhijindong Cave (China)." Atmosphere 12, no. 8 (2021): 967. http://dx.doi.org/10.3390/atmos12080967.
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Ensuring high air quality in the atmosphere of Zhijindong Cave is essential, for it is one of the most scenic in Asia and has received millions of tourists each year. Radon, as the most important radioactive carcinogen, is a priority and has been measured since just after its opening. However, an artificial exit was opened in 2002, and it is still unclear what the influence of that has been on the radon concentration in the cave atmosphere. In this study, we use RAD7 to monitor the spatiotemporal variations of radon concentration in the atmosphere of Zhijindong Cave for a whole year. The results show that radon concentration is generally higher in the hot season and lower in the cold season, and both with a distinct spatial differences. The highest measured radon concentration is 1691 Bq/m3, which is lower compared with the previous study. The reduced radon concentration could be caused by the strengthened cave ventilation due to the artificial exit. The temporal variation of radon concentration is related to the outside temperature change, while the spatial variation is mostly related to the different cave layers. The effective dose is negligible for tourists, but can be as high as 9.7 mSv for tour guides and 22.6 mSv for photographers.