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31.
The selection of new settlement areas and the construction of safe buildings, as well as rendering built‐up areas safe, are of great importance in mitigating the damage caused by natural disasters. Most cities in Turkey are unprepared for natural hazards. In this paper, Çanakkale, located in a first‐degree seismic zone and sprawled around the Sartçay Delta, is examined in terms of its physical vulnerability to natural hazards. Residential areas are analysed using GIS (geographic information system) and remote‐sensing technologies in relation to selected indicators. Residential areas of the city are divided into zones according to an evaluation of geological characteristics, the built‐up area's features, and urban infrastructure, and four risk zones are determined. The results of the analysis show that the areas of the city suitable for housing are very limited. In addition, the historical centre and the housing areas near Sartçay stream are shown to be most problematic in terms of natural disasters and sustainability.  相似文献   
32.
In this study, we investigated the effects of Matricaria chamomilla L. extract (MCE) on lipid peroxidation, antioxidant enzyme systems, and several liver enzymes in carbon tetrachloride (CCl4)-treated rats. Rats were divided into five groups. The first group (control group) was fed on standard feed. The rats in the other groups (CCl4, MCE50, MCE100, and MCE200) were injected intraperitoneally with 0.8?mL?kg?1 CCl4. Moreover, rats in the MCE50, MCE100, and MCE200 groups were gavaged with 50?mg?kg?1, 100?mg?kg?1, and 200?mg?kg?1 MCE, respectively. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, whole blood malondialdehyde (MDA) and glutathione (GSH) levels, and erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity levels were measured after 14 days of exposure. ALT and AST in the CCl4 group increased significantly in comparison to the control group (p?4, MCE50, MCE100, and MCE200 groups at different significance levels. In conclusion, the findings suggest that, depending on the dose administered, MCE decreases CCl4-induced damage and consequent oxidative stress in rats; it affects the antioxidant system positively.  相似文献   
33.
A potentiometric titration technique has been used to determine the stability constants for the various complexes of Co(II) and Cu(II) with L‐asparagine and from DNA base, e.g. adenine. Stability constants of ternary systems have been evaluated by the method suggested by Irwing‐Rossotti. In addition, the conditional constants were calculated as a function of pH. The maximum values of the conditional formation constants were found to be in accordance with the mixed‐ligand complex formation constants in a determined pH region. Furthermore, the molar fractions of different species from mixed complexes were calculated by means of formation constants. The values of stability constants of mixed‐ligand complexes at 25°C are as follows: log K= 5.25 for Co(II)‐L‐asparagine‐adenine; log K= 9.30 for Cu(II)‐L‐asparagine‐adenine. The ionic strength was kept constant at I = 0.20 with NaClO4.  相似文献   
34.
The paper presents a driver model, which can be used in a computer simulation of a curved ride of a car. The identification of the driver parameters consisted in a comparison of the results of computer calculations obtained for the driver-vehicle-environment model with different driver data sets with test results of the double lane-change manoeuvre (Standard No. ISO/TR 3888:1975, International Organization for Standardization [ISO], 1975) and the wind gust manoeuvre. The optimisation method allows to choose for each real driver a set of driver model parameters for which the differences between test and calculation results are smallest. The presented driver model can be used in investigating the driver-vehicle control system, which allows to adapt the car construction to the psychophysical characteristics of a driver.  相似文献   
35.
区域灾情评价模型   总被引:4,自引:0,他引:4  
自然灾害发生的次数和灾害种类与灾情强度密切相关,因此有必要对灾情强度进行合理的评价。首先用灾次指数Di和灾种指数Di′来量化单灾种的多发性和多灾种的群发性,提出了计算Di和Di′的方法,然后在此基础上建立了量化灾情强度指数Q的模型,该模型适用于单区域和多区域中多种灾害发生的情况。对北京市怀柔、平谷和海淀3个区进行了模型的实例应用,考虑洪灾、冰雹灾和旱灾3种灾害情况,结果表明,怀柔区的灾情强度指数高于平谷和海淀区,3种灾种中冰雹灾的灾情强度指数高达42.76%。  相似文献   
36.
Environment, Development and Sustainability - The depletion of fossil fuels and the fact that fossil fuels pollute the environment accelerated the trend toward environmentally friendly energy...  相似文献   
37.
38.
本文概述国内外污泥用作农肥处置的现状,全面分析了农田施用污泥产生的重金属积累,水处理凝聚剂及有害有机物的影响,过剩氮、磷的二次污染,恶臭及病原菌等问题,并提出相应的防治对策。加强管理,恰当处置,农田施用污泥是实现污泥资源化,解决污泥出路的好办法。  相似文献   
39.
Ozonation of three different synthetic pharmaceutical formulation wastewater containing two human antibiotics and a veterinary antibiotic has been studied to enhance the their biodegradability. The effects of pH and initial chemical oxygen demand (COD) value as well as addition of hydrogen peroxide on ozonation process were investigated. Total organic carbon (TOC), COD, biochemical oxygen demand (BOD), and aromatic content (UV254) were the parameters followed to evaluate the performance of ozonation process. Comparison of the biodegradability of selected wastewaters containing different antibiotics confirmed that the variation of biodegradability was associated with the target compound. While BOD5/COD ratio of veterinary antibiotic formulation wastewater was increased from 0.077 to 0.38 with an applied ozone dosage of 2.96 g/l, this ratio for human antibiotic I and human antibiotic II was increased from 0 to 0.1 and 0.27 respectively. Moreover the results of this investigation showed that the ozonation process is capable of achieving high levels of COD and aromaticity removals at about their natural pH values.  相似文献   
40.
In this study, the interaction between temperature and heavy metal stress was investigated in two wheat varieties (Triticum aestivum L. cv. Gerek-79 and Bolal-2973). Effects of different concentrations of lead and cadmium (0, 50, 100, 250, 500 mg l(-1)) simultaneously applied at various temperatures (8/4, 25/18, 35/26 degrees C day/night) to the seedlings were detected by measuring changes in the plant length, percentage of dry weight, chlorophyll (a, b, a/b), total soluble phenolics, and free proline. At the high cadmium concentrations, significant changes occurred in plant length and in the amounts of dry weight, chlorophyll, total soluble phenolics, and free proline. Significant differences were not observed in the parameters examined for the lead treatments. These data indicated that heavy metal toxicity increases in parallel with temperature. In addition, lead did not have any toxic effects on plants in sand-perlite mixture at 500 mg l(-1), whereas cadmium showed toxic effect even at such low concentrations as 50 mg l(-1).  相似文献   
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