Earthquake-related chemical and radioactivity changes of thermal water in Kuzuluk-Adapazan,Turkey

The movements of the North Anatolian Fault Zone (NAFZ) caused two devastating earthquakes within an 87-day interval, epicentered on G?lcük-Izmit (17 August, 1999) and Düzce-Bolu (12 November, 1999). The Kuzuluk geothermal area (KGA) is located in the middle of the epicenters and the distance between the geothermal area and the fault zone is less than 5 km. Hot water samples were collected from two thermal boreholes that supply hot water to the Kuzuluk thermal complex. The water samples taken prior to and after earthquakes were analysed by Neutron Activation and Atomic Absorption Spectroscopy. Particularly, increase in total a and total beta activities, in the content of Pb, Cr, Ni, Cu and decrease in the content of Fe, Zn, Cd, Mn, and Co are significant. The highest values are 75, 35, 12 and 65 ppb for Pb, Cr, Ni and Cu, respectively. The lowest values are 45, 55, 15, 135 and 6 ppb for Fe, Zn, Cd, Mn and Co, respectively.     

Arsenic adsorption from aqueous solutions by activated red mud

Heat treatment and acid treatment methods have been tested on red mud to increase its arsenic adsorption capability. The results indicate that the adsorptive capacity of red mud can be increased by acid treatment. This treatment causes sodalite compounds to leach out. As(III) and As(V) adsorption characteristics of activated red mud have similar tendencies with raw red mud. Batch adsorption studies have shown that activated red mud in dosages ranging from 20 to 100 g l(-1) can be used effectively to remove arsenic from aqueous solutions. The process is pH dependent, the optimum range being 5.8-7.5 for As(III) and 1.8-3.5 for As(V). The maximum removals are 96.52% for As(V) and 87.54% for As(III) for solutions with a final pH of 7.25 and 3.50, respectively, for the initial arsenic concentration of 133.5 micromol l(-1) (10 mg l(-1)), activated red mud dosage of 20 g l(-1), contact time of 60 min and temperature of 25 degrees C. The adsorption data obtained follow a first-order rate expression and fit the Langmuir isotherm well. Isotherms have been used to obtain the thermodynamic parameters. It was found that the adsorption of As(III) was exothermic, whereas As(V) adsorption was endothermic.     

Bioaccumulation of cesium-137 by biota in different aquatic environments

Macroalgae, isopods and fish species were exposed to 137Cs in brackish and sea water conditions for 18 days to determine radionuclide concentration factors. The concentration factors of 137Cs in brown shrimp and polychaete species were also investigated under brackish water conditions. At equilibrium, the concentration factors in macroalgae, isopod, fish, brown shrimp and polychate samples were found to be 2.5, 33, 2, 16 and 11 at 16 degrees C in brackish water conditions, respectively. The accumulation rate in macroalgae species was influenced by temperatures between 6 degrees C and 16 degrees C. The bioaccumulation of 137Cs in isopods at low salinity regime was increased significantly. At the same time, the bioaccumulation rate in macroalgae species also showed slight increase at low salinity. On the other hand, the bioaccumulation rate of 137Cs in the fish species in sea water was higher than in brackish water.     

Experimental studies on the biokinetics of 134Cs and 24Am in mussels (Mytilus galloprovincialis).

The biokinetics of 134Cs and 241Am in mussel species contaminated through water pathway has been studied under laboratory conditions. At equilibrium, the concentration factors for 134Cs and 241Am in small and large mussels were 2.80 and 2.57 and 200 and 150, respectively. The concentration factor of 134Cs in soft parts of the mussels was significantly high than whole body and shell tissue. However, the concentration factors of 241Am in soft parts and shell tissue samples were found to have similar rates. The depuration kinetics of the radionuclides were described by two-component exponential models. The biological half-lives at slow components between small and large mussels did not change significant, and were found to be 46.8-46.5 and 72.2-75.3 days for 134Cs and 241Am. The depuration kinetics of 134Cs and 241Am in soft parts described a single-component exponential model and the biological half-lives were found to be 29.4 and 41.1 days, respectively.     

Environmental analysis of Turkey’s aggregated and sector-level CO2 emissions

Environmental Science and Pollution Research - Turkey’s ecological footprint has recently been increasing, while its biocapacity has been decreasing. Furthermore, the country’s CO2...     

Using of leaching reactant obtained from mill scale in hydrometallurgical copper extraction

Environmental Science and Pollution Research - This study, which covered a set of leaching processes at a few stages, investigated the inclusion of iron found in mill scale, which is a waste of the...     

Evaluation of a fetus at risk for dihydropteridine reductase deficiency by direct mutation analysis using denaturing gradient gel electrophoresis

Dihydropteridine reductase (DHPR) is an enzyme involved in the recycling of tetrahydrobiopterin (BH₄), which is an obligate co-factor of the aromatic amino acid hydroxylases. DHPR deficiency is a rare, autosomal recessive disorder caused by mutations in the QDPR gene. DHPR-deficient patients are diagnosed by a lack of response to a low phenylalanine diet and by severe neurological symptoms. Final diagnosis is made by measurements of neurotransmitters and pterin metabolites in cerebrospinal fluid (CSF) and urine, in addition to DHPR enzyme activity, which can be assessed in whole red blood cells. Treatment of DHPR deficiency can be difficult and the outcome is not always satisfying, even if all treatment strategies are followed. Therefore prenatal diagnosis is of great importance in affected families. Prenatal diagnosis is possible by measuring DHPR activity in different cell types but this is time consuming. More than 25 different mutations have to date been identified in the QDPR gene and direct identification of a mutation in a fetus would be easy and rapid. We have developed a method based on denaturing gradient gel electrophoresis (DGGE) for the analysis of the QDPR gene. The method is useful for rapid and simultaneous scanning of all exons and flanking intronic sequences of the QDPR gene. We describe the first prenatal diagnosis conducted using this method. Copyright © 2001 John Wiley & Sons, Ltd.     

乌梁素海湿地鸟类栖息地生态服务功能评估探讨

本文通过收集近30年鸟类种类及种群数据变化的资料,分析乌梁素海不同鸟类栖息环境的栖息地服务功能,从而评估乌梁素海湿地鸟类栖息地的综合生态服务功能。评估结果表明:乌梁素海湿地鸟类栖息地综合生态服务功能为不好。