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71.
Istanbul is the largest city in Turkey with an area of around 5750 km2 and population of around 10.58 M (2000). The population is increasing because of mass immigration. Planned and unplanned housing are increasing while green areas are decreasing in area. Rapid, uncontrolled and illegal urbanization accompanied by insufficient infrastructure has caused degradation of forest, water basin and barren lands in the metropolitan area, especially within the past two decades. The study includes taking administrative planning decisions about the development of urban sustainability in the metropolitan area of Istanbul, producing rationalist solutions to the problems in environmental and natural resources, and conservation of small-scale (historical, tourist, residential, industrial, etc.) specific urban areas. By the help of this study, settlement suitability analyses have been achieved according to the natural thresholds of the area. Additionally, some kinds of formations, which may limit the development of the metropolitan area of Istanbul, such as natural structures, natural structure, ecological corridors and natural hazard areas, have been defined and developed model on the ArcGIS 9.1 platform. In the light of the policies of the European Union about sustainable cities, environmental impact assessments and sustainability policies have been determined for both the existing settlements and sustainable development areas.  相似文献   
72.
The continuous electrochemical treatment of industrial textile wastewater in a tubular reactor was investigated. The synthetic wastewater was based on the real process information of pretreatment and dyeing stages of the industrial mercerized and non-mercerized cotton and viscon production. The effects of residence time on chemical oxygen demand (COD), color and turbidity removals and pH change were studied under response surface optimized conditions of 30 °C, 25 g/L electrolyte concentration and 3505 mg/L COD feed concentration with 123.97 mA/cm2 current density. Increasing residence time resulted in steady profiles of COD and color removals with higher treatment performances. The best column performance was realized at 3 h of residence time as 53.5% and 99.3% for COD and color removals, respectively, at the expense of 193.1 kWh/kg COD with a mass transfer coefficient of 9.47 × 10−6 m/s.  相似文献   
73.
In this study, denim fabrics were produced with yarns obtained from cotton fibers (CO), recycled cotton fibers obtained from yarn wastes (r-CO), and fibers produced from recycled PET bottles (r-PET). Enzyme and stone washing processes were applied systematically on these fabrics. Mass per unit area, breaking force, elongation at max force, tear strength, air permeability, and circular bending rigidity of fabrics were measured. The findings showed that r-CO fiber has negative effect on tear and breaking force. Breaking force, elongation at max force, and tear strength values of the fabrics increased depending on the increase in r-PET content. However, fabric handle was negatively affected associated with the r-PET ratio due to the increase in stiffness. Mass per unit area, breaking force, air permeability, and circular bending rigidity values of fabrics decreased after the washing processes. The effect of fibers on enzyme- or stone-washed fabrics showed a change according to finished fabrics. It can be said that fabrics containing r-PET are more resistant than cotton and recycled cotton in various aggressive denim washing methods such as bleaching or different washing process conditions such as rising temperature, and time.  相似文献   
74.
In this study, the chemical and sensory qualities of fishburger produced from tilapia (Oreochromis niloticus) were investigated during frozen storage (–18 °C) over 8 months. The ratios of crude protein, lipid, moisture, crude ash, and polyunsaturated fatty acids in tilapiaburger were found to be 17.82%, 5.29%, 66.68%, 2.56% and 7.95% respectively. At the end of the study, the total volatile basic nitrogen value was found to have fluctuated throughout the storage periods. The highest thiobarbituric acid value was found at the 7th month as 0.142 mg malonaldehyde/kg. The peroxide value was 0.18 meq/kg at the beginning of the storage but increased to 5.03 meq/kg at 6th month of storage and then decreased to 0.82 meq/kg at the 8th month. The level of free fatty acids was 2.73% oleic acid at the beginning but reached 4.14% in the first month of storage and then increased to 5.92% at the end of the storage. pH values ranged between 8.01 and 7.97. At the end of the storage period, sensory quality criteria were scored as quite near those of the fresh samples.  相似文献   
75.
The real structured singular value (RSSV, or real μ) is a useful measure to analyze the robustness of linear systems subject to structured real parametric uncertainty, and surely a valuable design tool for the control systems engineers. We formulate the RSSV problem as a nonlinear programming problem and use a new computation technique, F-modified subgradient (F-MSG) algorithm, for its lower bound computation. The F-MSG algorithm can handle a large class of nonconvex optimization problems and requires no differentiability. The RSSV computation is a well known NP hard problem. There are several approaches that propose lower and upper bounds for the RSSV. However, with the existing approaches, the gap between the lower and upper bounds is large for many problems so that the benefit arising from usage of RSSV is reduced significantly. Although the F-MSG algorithm aims to solve the nonconvex programming problems exactly, its performance depends on the quality of the standard solvers used for solving subproblems arising at each iteration of the algorithm. In the case it does not find the optimal solution of the problem, due to its high performance, it practically produces a very tight lower bound. Considering that the RSSV problem can be discontinuous, it is found to provide a good fit to the problem. We also provide examples for demonstrating the validity of our approach.  相似文献   
76.
The effects of gamma radiation on the fecundity, fertility, longevity, development and level of inherited sterility in the Mediterranean flour moth Ephestia kuehniella were determined. Newly emerged virgin Mediterranean flour moth adults were irradiated with 100, 200, 400 and 600 Gy in a 60Co irradiator with a source strength of ca. 3811 Ci and a dose rate of ca. 1 Gy/min. Laboratory studies revealed that radiation did not effect the longevity of irradiated male and female adults. Inherited deleterious effects of gamma radiation were observed in the F1 and F2 generations. Fecundity and the daily egg laying pattern of irradiated and unirradiated females mated to irradiated males was not significantly different from untreated controls. Adverse effects of gamma radiation were observed in the percentage egg hatch and rate of development. Levels of sterility in the P1, F1 and F2 generations were higher than that of untreated controls. The doses of radiation also had a significant effect on the time from oviposition to larval eclosion or adult emergence. Mortality increased with radiation dose. The incidence of larval and pupal mortality was higher in the F2 than in the F1 generation.  相似文献   
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