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[en] The detection of radon in a building must allow to determine if all or part of the building presents a yearly average value of the radon voluminal activity is over to one or several values of interest. The measurement of radon voluminal activity in a building is codified by the AFNOR NF M60-771 norm, relative to the methodology enforced to the radon detection in buildings. It applies to any type of buildings whatever be the type of interface, the area and the ventilation mode where the ground is the principal source of radon in inside air. In the particular case of spa facilities, the presence of radon in buildings is in relation with the ground nature but also with the water present in the buildings and close environment. The present document presents the methodology applicable to the radon detection in a spa facility. It is founded on the AFNOR NF M60-771 norm and on the results of studies realised by I.R.S.N. in three French spa facilities. The implementation of this methodology requires knowledge relative to radon and buildings. It is thus the responsibility of relevant agencies. (N.C.)
[en] Variation in earth gas level like radon in soil and groundwater is a proven technique for tracing the changes in stresses due to seismotectonic activities. Radon concentrations were measured and investigated in Jooshan hot spring complex, SE of Iran, near Golbaf-Sirch fault system from December 2011 until March 2012. Afterward, by considering and studying environmental parameters, the relationship between radon anomalous decline and all earthquakes with ratio D/R that introducing by Dobrovolsky et al. was examined. So before earthquakes, the correlation between this ratio and level of variation in radon concentration in magnitude ranging from 2.6 to 5.4 has been studied and the correlation coefficient of 0.74 was obtained. This research shows a good correlation between groundwater radon variations and such earthquake parameters. (author)
[en] Full text of publication follows: Measurement of background radiation is very important from different points of view especially to human health. In some cases exposure rate near hot and mineral springs are higher than those of normal areas. The high background radiation of hot and mineral springs is primarily due to the presence of very high amounts of Ra 226 and its decay products. In this research, environmental gamma radiation of hot and mineral springs in Khorasan, Mazandaran and Sareeyn town in Ardabil province have been measured. Equipment used in this work included: a survey meter (R.D.S. -110), a tripod and an aluminium frame to hold the survey meter horizontally.R.D.S. -110 is a microprocessor controlled detector. This survey meter has been designed for monitoring X and 'rays and' radiation. Measurements were carried out at one meter above water level in the vicinity of hot and mineral springs. Dose rates were recorded for one hour. The average of all recorded dose rates over one hour period was taken as the exposure rate for each station. The results indicate that in Khorasan province the highest and lowest annual absorbed dose rates were equal to 10.80 mSv/y at Shanigarmab and 0.52 mSv/y at Nasradin source respectively. In Mazandaran province maximum and minimum exposure rates equal to 54.4 and 0.53 mSv/y were obtained at the surface of Talleshmahalleh and Ghormerz sources. Exposure rates at the vicinity of Sarein sources were not very different and ranged from 1.39 to 1.59 mSv/y. The results indicate that in Khorasan province Shahingarmab hot spring has the highest annual absorbed dose rate (10.80 mSv/y) and Nasraddin in Sarbisheh has the lowest level of radiation (0.62 mSv/y). In Mazandaran province Taleshmahalleh hot mineral spring has the highest annual absorbed dose rate (54.41 mSv/y) and Ghormerz mineral spring has the lowest radiation level (0.53 mSv/y). Also in Sareeyn (in Ardabil province) Abechashm source has the highest annual absorbed dose rate (1.59 mSv/y) and Jeneral spring the lowest (1.39 mSv/y). (authors)
[en] Radon, a natural radioactive gas, takes an important part in public exposure. Radon is a colorless, odorless and chemically inert gas. It is generated through the disintegration of the 238U series. Its parent nucleus 226Ra is present in soil, waters and rocks. Radon and its radioactive progenies are recognized as the main source of public exposure from the natural radioactivity. In general, the concentration of radon depends on four factors: nature of the source, power of emanation, transport properties of the medium and dispersion properties of the environment. Due to its relatively long half - life (3.82 days), radon can stay relatively long in the atmosphere before it decomposes. Radon and its progenies are very important from radiation protection point of view. In this paper are presented the results of radon activity concentration and estimate of the annual effective dose rate in air of mineral and thermal springs of Bosnia and Herzegovina. Measurements were taken at the following locations: Slatina Spa, Reumal Spa, Mali Guber, Ocna Voda, Voda Ljepotica, Terme, Bazeni Slavinovici, Toplice, Muska Voda, Voda Miladije, Petrak, Princess, Kiseljak Teslic, Kiseljak Kozluk, Kiseljak Husino, Panonika Tuzla, Sarajevski Kiseljak, Kiseljak Dubnica. Radon activity concentration at outdoor species of the surveyed mineral and thermal sources was in the interval of 11-67 Bq/m"3. The annual effective dose for radon outdoors, was in the interval of 0.02-0.35 mSv/y. The measurements where being done by AlphaGUARD radon portable measuring system. (author).
[en] Radioactivity (226Ra, 137Cs, 232Th and 40K) levels in peloids from some Cuban spas (San Diego, Elguea, Santa Lucia and Cajio) have been studied. The radionuclide concentration ranges in peloids on Bq kg-1 dry weight varied as follows: 226Ra = 6-1800, 137Cs = < 1.6-5.0, 232Th = 6-38 and 40K = 47-365, and are in the same order of concentrations reported for therapeutic peloids used worldwide. The estimated annual equivalent dose in 226Ra-enriched peloids, considering the short exposition times associated with the usual therapeutic practices in Cuban spas, is well below accepted equivalent dose values to the skin for members of the public. Therefore, radioactivity levels present in peloids from the studied Cuban spas are not significant and do not represent an impediment for its use with therapeutic purposes. (author)
[en] In the present work have studied two samples with the same pigment, Egyptian Blue, but from different sources. The difference between them is caused by the functionality. In the case of Nefertari's tomb is decorating interior rooms carved into rock in which they would not suffer any damage since it does not accessed to that place anymore. In the case of Balneum's baths is decorating very warm and humid rooms, and should resist deterioration resulting from human activity during the use of these baths. (Author) 38 refs.
[en] The mineral springs of scuol-Tarasp are located in the lower Engadine Valley, Graubuenden, south eastern Switzerland. In the last century, they have been investigated with respect to their basic chemical parameters. These springs yield a highly mineralized carbon dioxide water, with large quantities of free CO2. Some of the springs also contain high amounts of ammonia. In order to better understand the origin of the water of the different springs, 13 were investigated, focusing this study on the ammonia content and the isotopic composition of the ammonia in the waters. It results from the study that 7 of the 13 springs contain ammonia. Based on the isotope and chemical results we suggest an origin of that ammonia by natural processes as water-rock interaction within the sedimentary and mantle rocks along the water flow path resulting in the enrichment of ammonia as seen in the investigated spring waters. (author)
[en] The invention provides a mechanism for applying holddown force at the upstream end of the fuel assembly without changing the loading of the core barrel and without requiring a latching mechanism. In addition, it reduces the effect of length variations on spring designs. According to the present invention, holddown force is applied not to the fuel-assembly structure but to a holddown column that either fits within a center guide-tube or takes the place of the center guide-tube and fits through openings in the spacer grids. The holddown column is made of the same material as the core barrel. As a result, the thermal expansion of the core barrel, which is the source of much of the variation that the springs must accomodate, is approximately matched by the thermal expansion of the holddown column. Also, since the holddown column can be made of stainless steel, rather than the Zircaloy typically used in the fuel-assembly structure, the effect of irradiation growth is mimimized. (auth)
[en] The frequency range over which a mount can isolate a mass from a vibrating base (or vice versa) is often limited by the mount stiffness required to support the weight of the mass. This compromise can be made more favourable by employing non-linear mounts with a softening spring characteristic such that small excursions about the static equilibrium position result in small dynamic spring forces and a correspondingly low natural frequency. This paper concerns the force-displacement characteristic of a so-called quasi-zero-stiffness (QZS) mechanism which is characterised by an appreciable static stiffness but very small (theoretically zero) dynamic stiffness. The mechanism studied comprises a vertical spring acting in parallel with two further springs which, when inclined at an appropriate angle to the vertical, produce a cancelling negative stiffness effect. Analysis of the system shows that a QZS characteristic can be obtained if the systems parameters (angle of inclination and ratio of spring stiffness) are opportunely chosen. By introducing the additional criterion that the displacement of the system be largest without exceeding a desired (low) value of stiffness an optimal set of parameter values is derived. Under sufficiently large displacements the stiffness of the QZS mechanism can eventually exceed that of the simple mass-spring system and criteria for this detrimental scenario to arise are presented