Mehmet N. Kumru

R-mode factor analysis applied to the distribution of elements in soils from the Aydın basin, Turkey

Soil samples collected at approximately 4-km intervals within the Aydin basin, Turkey, were analysed by Energy Dispersive X-ray Fluorescence Spectroscopy, Gamma Spectroscopy and Alfa Spectroscopy for the elements Ba, Ce, Cr, Fe, Mn, Ni, Rb, Sr, Ti, Zn, Zr; K (radioactive potassium), 232Th (equivalent thorium, eTh), 238U (equivalent uranium, eU) and Ra. R-mode factor analysis was used to describe the relationship among 15 remotely sensed and geochemical and industrial variables for the basin. Principal component and varimax factor rotation were applied to the data. Because varimax factor loading values show the best results, these were used in interpreting. Four factors were extracted in topsoil data and account for 78% of the total data variance. These are named as an industrial, a mineral/an agricultural, igneous and radioactive factors.

Determination of radium-226 in environmental samples by the collector chamber method

Abstract Two established methods for measuring Ra-226 have been combined and adapted and applied in the uranium mining industry. The optimum conditions have been established. Accuracy, precision, cost efficiency and relatively short preparation time make this a useful method.

Determination of radioactivity and heavy metals of Bakirçay river in Western Turkey.

In this study, radioactive and heavy metal contaminations in sediments and waters of Bakırçay River in Western Turkey were investigated to determine their pollution potential. The radium concentrations in the water samples were measured using the collector-chamber method. The radioactivities of (40)K, (226)Ra and (232)Th in sediments and soils were found to be 45.30 to 839.19 Bq kg(-1), 35.26 to 160.57 Bq kg(-1) and 1.86 to 131.49 Bq kg(-1), respectively. The activity of (226)Ra in the water samples ranged from 0.09 to 0.36 Bq/L. To determine the radiological hazard of natural radioactivity in the samples, the external terrestrial gamma dose rate in air (n Gyh(-1)), annual effective dose rate (mSv y(-1)), radium equivalent activity (Bq kg(-1)) were calculated and compared with internationally recommended values.

POSSIBLE URANIUM RICH AREAS IN THE AEGEAN REGION OF TURKEY

Abstract The Buyuk Menderes rivers originates near Afyon city and flows through the mountains of Ortadaǧ, Cubuk, Babadaǧ, Cevizli and Besparmak. The river enters into the Aegea Sea near Soke. This 500 km long river passes through a large area in the central Aegean region of Turkey. The geological structure contains mostly metamorphic and volcanic rocks of Paleozoic, Mesozoic and Neogene ages. Water, sediment and soil samples were collected from the river at 1 km intervals and near its tributaries. The investigations extended from the end of the river near the Aegean Sea to its source. Eight anomalous areas rich in uranium were determined along the river. Three of them are neer known uranium deposits, but the others are not.

Factor analysis applied to distribution of elements in western Turkey

This paper examines the results of R-mode factor analysis performed on four radionuclides and two elements data from a geochemical survey from western Turkey. Sediment and soil samples numbering 321 were collected along the Gediz river and analysed for 238eU, 232eTh, 40K, 226Ra, Mg and Pb. Two factors in soil and sediment, which account for 59% and 56% of the total variance, respectively, were extracted and named as geological structure and volcano.

Factor analysis in the geochemical studies along the Gediz river, Turkey

Water samples collected from 321 sampling points at 1 km intervalsat a site located close to the industrial and geological areas in the Gedizriver were analysed for U, Ra, Na, Mg, Mn, K, Ni, Cd, Co, Pb, Al, Fe, Cr,Zn, Cu and Ca. Heavy metal concentrations in the samples were determined byatomic absorption spectroscopy, laser excited fluorescence, and radon collectorchamber. Factor analysis was used to describe the relationship among 16 elements.Four factors were extracted and they account for 67% of the total variancein the data. These factors are named as industry, sea, agriculture and geology.According to this result, not only industrial plants but also geological structureand agricultural activities were seen to contribute in polluting of the riverwater. Beside, these factors have shown that a lot of agricultural activitiesand a sharp increase in the population of the Gediz basin, and industrialdevelopment related to above reasons speed up pollution of water sources andbecome a potential risk on the unpolluted sources.

Investigations of some parameters of the collector chamber method for the determination of radium-226

Abstract The aim of this study is to examine some parameters of the Collector chamber method that was developed as a new method for determining the concentrations of 226 Ra existing in environmental samples. The type and diameter of the collector, the volume of the collector chamber and the voltage employed were chosen as parameters. To obtain the highest yield, the diameter of the collector plate should be 4.5 cm, the collector should be copper and, the volume of the collector chamber should be 2.47 l , and the voltage should be 600 V.

Natural radioactivity levels of geothermal waters and their influence on soil and agricultural activities

All over the world geothermal sources are used for different purposes. The contents of these waters are important to understand positive/negative effects on human life. In this study, natural radioactivity concentrations of geothermal waters were investigated to evaluate the effect on soils and agricultural activities. Geothermal water samples were collected from the Seferihisar Geothermal Region, and the radon and radium concentrations of these waters were analysed using a collector chamber method. Also soil samples, which are irrigated with geothermal waters, were collected from the surroundings of geothermal areas, and natural radioactivity concentrations of collected samples (U, Th and K) were determined using an NaI(Tl) detector system. The activity concentrations of radon and radium were found to be 0.6-6.0 and 0.1-1.0 Bq l(-1), respectively. Generally, the obtained results are not higher compared with the geothermal waters of the world. The activity concentrations in soils were found to be in the range of 3.3-120.3 Bq kg(-1) for (226)Ra (eU), 0.3-108.5 Bq kg(-1) for (232)Th (eTh), 116.0-850.0 Bq kg(-1) for (40)K (% K).

Differential dose contributions on total dose distribution of 125I brachytherapy source

This work provides an improvement of the approach using Monte Carlo simulation for the Amersham Model 6711 (125)I brachytherapy seed source, which is well known by many theoretical and experimental studies. The source which has simple geometry was researched with respect to criteria of AAPM Tg-43 Report. The approach offered by this study involves determination of differential dose contributions that come from virtual partitions of a massive radioactive element of the studied source to a total dose at analytical calculation point. Some brachytherapy seeds contain multi-radioactive elements so the dose at any point is a total of separate doses from each element. It is momentous to know well the angular and radial dose distributions around the source that is located in cancerous tissue for clinical treatments. Interior geometry of a source is effective on dose characteristics of a distribution. Dose information of inner geometrical structure of a brachytherapy source cannot be acquired by experimental methods because of limits of physical material and geometry in the healthy tissue, so Monte Carlo simulation is a required approach of the study. EGSnrc Monte Carlo simulation software was used. In the design of a simulation, the radioactive source was divided into 10 rings, partitioned but not separate from each other. All differential sources were simulated for dose calculation, and the shape of dose distribution was determined comparatively distribution of a single-complete source. In this work anisotropy function was examined also mathematically.

R-mode factor analysis applied to the exploration of radioactivity in the Gediz River

Sediment samples were collected from the river bed at 10 km intervals and have been analysed for eU, eTh, %K,226Ra, Ca, Ti, Mn, Zn, Rb, Sr, Y, Zr, Ba, La and Ce. R-mode factor analysis was used to describe the relationship among 15 remotely sensed and geochemical data sets (variables) for the Gediz River. Four factors were extracted in the sediments and they account for 57.6% of the total variance in the data. These factors are interpreted as granite (felsic), economy, volcano and industry factors, respectively.