一株碱性脱除硫酸盐细菌的筛选及其生长特性研究

生化铁碱溶液催化法气体脱硫方法（简称DDS法）具有良好脱硫效果，但是DDS溶液在脱硫后会导致脱硫能力降低，为了达到使DDS脱硫残液得到再生的目的，从自然环境中筛选能够使DDS脱硫残液得到再生的微生物并对其进行了研究。通过富集培养及纯化，从黑龙江省五大连池火山口附近土样中筛选出一株碱性条件下脱除硫酸盐的菌株WT-1。对该菌株的生长曲线进行了测定，培养4～6 h菌株进入对数期，20 h左右到达稳定期。并研究了温度、pH值和摇床转速对其生长特性和活性的影响，结果表明，该菌株的最适生长条件为：温度35～45℃，pH值8，摇床转速120 r/min。同时，脱硫试验表明WT-1确实具有脱除硫酸盐的能力。     

Atmospheric deposition of polycyclic aromatic hydrocarbons to Izmit Bay, Turkey

Wet deposition and dry deposition samples were collected in an urban/industrialized area of Izmit Bay, North-eastern Marmara Sea, Turkey, from September 2002 to July 2003. The samples were analyzed for sixteen polycyclic aromatic hydrocarbon (PAH) compounds by using HPLC-UV technique. Wet and dry deposition concentrations and fluxes of PAHs were determined. The results showed that PAH concentrations were high because of industrial processes, heavy traffic and residential areas next to the sampling site. Total dry deposition flux of the fifteen 3-6 ring PAHs was 8.30 microg m(-2)day(-1), with a range of 0.034-1.77 microg m(-2)day(-1). The total wet deposition flux of the fifteen 3-6 ring PAHs was 1716 microg m(-2) 11 month(-1), with a range of 10-440 microg m(-2) 11 month(-1). Significant seasonal differences were observed in both types of deposition samples. The winter fluxes of total PAHs were 1.5 and 2.5 times greater than those of the warm period for wet and dry deposition samples, respectively. Factor analysis of dry deposition samples and back trajectory analysis of wet deposition samples were also used to characterize and identify the PAH emission sources in this study.     

The trace metal levels in milk and dairy products consumed in middle Anatolia—Turkey

In this study, aluminium (Al), lead (Pb), cadmium (Cd), selenium (Se) and arsenic (As) contents in milk and different dairy product samples were measured. Pb, Cd, As, Al and Se contents in the milk and different dairy products ranged from 0.054 mg/kg (milk powder)?1.100 mg/kg (Ka?ar cheese), 0.009 mg/kg (whey powder and yogurt)?1.051 mg/kg (Tulum cheese), 0.010 mg/kg (whey powder)?0.146 mg/kg (butter), 2.848 mg/kg (ice cream)?8.778 (drained yogurt) and n.d. (ice cream, milk and whey powder, yogurt, ayran and Lor cheese)?0.434 mg/kg (Tulum cheese), respectively. The 75% of White and Ka?ar cheeses, 50% of Lor and 12.5% of Tulum cheese samples contained higher Pb according to the legal limits established by the Turkish Food Codex and European Communities regulation and 12.5% of Tulum cheese sample contained Cd. It was concluded that Pb contents of milk and dairy products from this region might be highly hazardous to human     

Implementation of Neural Networks for Classification of Moss and Lichen Samples on the Basis of Gamma-Ray Spectrometric Analysis

Mosses and lichens have an important role in biomonitoring. The objective of this study is to develop a neural network model to classify these plants according to geographical origin. A three-layer feed-forward neural network was used. The activities of radionuclides ((226)Ra, (238)U, (235)U, (40)K, (232)Th, (134)Cs, (137)Cs and (7)Be) detected in plant samples by gamma-ray spectrometry were used as inputs for neural network. Five different training algorithms with different number of samples in training sets were tested and compared, in order to find the one with the minimum root mean square error. The best predictive power for the classification of plants from 12 regions was achieved using a network with 5 hidden layer nodes and 3,000 training epochs, using the online back-propagation randomized training algorithm. Implementation of this model to experimental data resulted in satisfactory classification of moss and lichen samples in terms of their geographical origin. The average classification rate obtained in this study was (90.7 +/- 4.8)%.     

溧阳市1985~2011年环境空气质量变化规律的模糊综合评价

选用模糊综合评价法,对溧阳市1985~2011年环境空气质量进行了综合评价,选用SO2、NO2、TSP/PM10作为评价因素,通过计算各评价因素权重分配系数和隶属度,分析了长期空气环境质量变化趋势。结果表明:TSP/PM 10为1985年以来溧阳市首要环境空气质量制约因素,20世纪80年代中期全市空气质量主要隶属于一级标准,20世纪80年代后期主要隶属于二级标准,20世纪90年代初期主要隶属于三级标准,20世纪90年代中后期至今主要隶属于二级标准,近几年受TSP/PM1 0因素影响,在三级标准的隶属度有上升趋势;自20世纪90年代中期始,NO 2超越SO2成为继PM 10之后制约空气质量的第2大因素;经济发展对环境空气质量的规模效应较为显著,技术减排效应逐步显现。     

Determination of arsenic levels in the water resources of Aksaray Province, Turkey

Arsenic levels were determined in 62 stations utilized as drinking and potable water resources by local community for Turkey's Aksaray Province (4589 km(2); 980 m above sea level). The samplings were implemented every two months for 1 year. The arsenic values were found to be ranging between 10 and 50 μg/L in 22 points and were found to be >50 μg/L in 5 stations, according to the mean value of the 6 samples. WHO and the Turkish Standards have permitted an arsenic concentration of 10 μg/L in drinking waters. The multivariate statistical technique, cluster analysis (CA), followed by principal component analysis (PCA) were applied to the data on 17 water quality parameters in 47 stations that are used for drinking and other domestic resources. Two significant sampling locations were detected based on the similarity of their water quality. The chemical correlations were observed in the two sub-sampling locations by Principal Component Analysis.     

Genotoxic effects and molecular docking of 1,4-dioxane: combined protective effects of trans-resveratrol

Environmental Science and Pollution Research - In this study, the protective effects of trans-resveratrol (t-resv) against 1,4-dioxane-induced toxicity in meristematic cells were investigated. For...     

The co-movements between geothermal energy usage and CO2 emissions through high and low frequency cycles

Environmental Science and Pollution Research - Geothermal energy is considered environmentally friendly than fossil fuel sources, and geothermal power plants are expected to have a low carbon...     

DNA damage effect of cyprodinil and thiacloprid in adult zebrafish gills

Cyprodinil and thiacloprid are two of the most commonly used pesticides in Turkey. It is more likely to reach humans or animals due to their widespread use. This study aims to investigate whether there is a DNA damage risk due to cyprodinil and thiacloprid exposure. Zebrafish, which is used as a model organism in health and environmental research, and comet assay were chosen to demonstrate this damage. Ten zebrafish per group were exposed to 2 different concentrations for each pesticides (0.31 and 0.155 mg/L for cyprodinil and 1.64 and 0.82 mg/L for thiacloprid) for 21 days. After, gills were excised and comet assay was performed. Photos of an average of 50 cells per slide were taken and were analyzed with visual evaluation program. DNA damage was found to be increased in the 0.31 mg/L cyprodinil, 0.82 mg/L thiacloprid, and 1.64 mg/L thiacloprid treatment groups when compared to the control group (p < 0.001). Average tail DNA percentage parameter values were 9.45 ± 0.51, 10.30 ± 0.34, 11.17 ± 0.33, and 2.47 ± 0.06 respectively. Cyprodinil and thiacloprid were identified as genotoxic agents that should be investigated further.

     

Monitoring forest structure at landscape level: a case study of Scots pine forest in NE Turkey

This study aims to investigate the change in spatial-temporal configuration of secondary forest succession and generate measurements for monitoring the changes in structural plant diversity in Yaln?zçam Scots pine forest in NE Turkey from 1972 to 2005. The successional stages were mapped using the combination of Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). Forest structure and its relationship with structural plant diversity along with its changes over time were characterized using FRAGSTATS. In terms of spatial configuration of seral stages, the total number of fragments increased from 572 to 735, and mean size of patch (MPS) decreased from 154.97 ha to 120.60 ha over 33 years. The situation resulted in forestation serving appropriate conditions for plant diversity in the area. As an overall change in study area, there was a net increase of 1823.3 ha forest during the period with an average annual forestation rate of 55.25 ha year^?1(0.4% per year). In conclusion, the study revealed that stand type maps of forest management plans in Turkey provide a great chance to monitor the changes in structural plant diversity over time. The study further contributes to the development of a framework for effective integration of biodiversity conservation into Multiple Use Forest Management (MUFM) plans using the successional stages as a critical mechanism.