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941.
942.
Heeyeun Yoon 《Journal of Environmental Planning and Management》2018,61(7):1113-1136
This study aimed to unpack the dynamic proximity effects of a park on residential values in the urban regeneration context: first by the development phase of the park, and second, by specific characteristics of the residential units. The study site is the Dream Forest in Seoul, South Korea, and the study period is from 2006 to 2015. The two-fold multilevel regression analysis suggests that the Dream Forest began exerting proximity effects from the time of site acquisition by the city, which peaked at a 3.7% price increment per 100-meter distance to the park from a prototypical housing unit, soon after the public announcement of the park procurement plan. During construction, inauguration and stabilization, the effect has remained at around 3.0%. The analysis also suggests that the proximity effect applies unevenly to housing units: apartment type or older housing units are more sensitive to the externality effects than their counterparts – multifamily type or newer housing units. 相似文献
943.
煤层注水抑制瓦斯解吸效应试验研究 总被引:4,自引:0,他引:4
煤层注水宏观上具有疏松煤体、卸压排放瓦斯的效应,这是人们对煤层防突机理的初步认识。为进一步认清煤层防突机理,采用实验室试验和现场测试相结合的方法,在实验室中使干燥煤样在煤样罐中预先吸附瓦斯来模拟原始煤层,然后向试验煤样高压注入水分,注水后再测试瓦斯解吸等温特性曲线、瓦斯解吸速度及残存瓦斯含量。测验结果表明,注水后瓦斯解吸等温特性曲线上移,初始瓦斯解吸速度变小且衰减速度变慢,残存瓦斯含量增加,现场测试钻屑瓦斯解吸指标值降低。通过分析测试结果认为,注水后,水分进入并留存在煤体的微孔隙中,对煤层瓦斯具有抑制解吸效应,而抑制解吸效应可以降低瓦斯初始解吸速度,使瓦斯解吸过程变缓,避免瓦斯突然快速解吸。这是煤层注水防治煤与瓦斯突出的一项重要机理。 相似文献
944.
利用不同尾矿砂取代率的混凝土梁斜截面受剪性能进行试验研究,结果表明:尾矿砂绿色混凝土梁与普通混凝土梁的受力破坏形态相似,在相同荷载下,尾矿砂绿色混凝土梁的箍筋应变大于普通混凝土梁,跨中挠度随着剪跨比的增大而增大;从开裂荷载来看,40%替代率的尾矿砂绿色混凝土梁抗裂性能最好,极限承载能力最高。并根据试验结果建立了较为合理的尾矿砂绿色混凝土梁斜截面受剪承载力计算公式。 相似文献
945.
In this study we present a novel research approach to obtaining behavior-based evidence of regional climate change attitudes, using the 2011 Fukushima nuclear plant incident as a natural experiment. Our approach allows us to produce the first non-survey-based empirical evidence of a trans-Atlantic divide in public opinion on the environment and climate change that investors assign to fossil-based and renewable energy. This value is based on the perceived potential of these fuel types to substitute for nuclear generation in the aftermath of the Fukushima crisis. We carry out an event study to examine differences in abnormal returns of global coal and renewable energy companies on European and American stock exchanges. We find that investors trading on U.S. markets exhibit a significantly more favorable perception of coal stock profitability, while investors trading on European exchanges display a more favorable perception about profitability of renewable energy stocks. 相似文献
946.
The effects of deltamethrin at acute and sublethal concentrations on some hematological and biochemical profiles in the Indian major carp Labeo rohita have been examined. The lethal concentrations (LC50) of deltamethrin for 24 and 96 h were found to be 0.44 and 0.38 mg L?1, respectively. During acute treatment (24 h), hemoglobin (Hb), hematocrit (Hct), red blood cell (RBC), white blood cell (WBC), mean cellular volume (MCV), mean cellular hemoglobin (MCH), and mean cellular hemoglobin concentration (MCHC) values were significantly increased compared to control group. Plasma glucose, protein, cholesterol, albumin, globulin, triglyceride, and glycogen in gill and muscle were significantly decreased. Upon sublethal treatment (0.044 mg L?1, 10th of 24 h LC50), RBC and the biochemical parameters, except glucose and cholesterol, decreased significantly, while MCV, MCH, and MCHC values increased up to the 28th day and then declined. Cholesterol level was significantly increased throughout the study period. A biphasic response in the levels of Hb, Hct, WBC, and glucose were observed during sublethal treatment. 相似文献
947.
The interaction between a cationic dye Methylene Blue (MB) and an anionic surfactant sodium dodecyl sulfate (SDS) with the presence of Cd2+ was investigated spectrophotometrically in a certain concentration range. The spectrophotometric measurements of dye-metal ion-surfactant system were carried out. The results indicated that the SDS concentration had a significant influence on the dye spectrum, while the addition of Cd2+ hardly caused change of the maximum value of absorbance. According to this observation, we concluded that electrostatic and hydrophobic interaction between dye and surfactant occurred up to a certain level, and the homo-ions Cd2+ almost exerted no effect on the dye-surfactant complexation, establishing a theoretical foundation for simultaneous removal of organic dye and heavy metal using foam fractionation. Meanwhile, the effects of their interaction on foam performance were investigated. The results showed that the addition of Cd2+ favored the tendency to ameliorate foam properties just contrary to MB. The feasibility of foam separation for dye and heavy metal removal from simulated wastewater was also confirmed using a continuous foam fractionator. In the simultaneous removal process, with the initial SDS concentration ranging from 0.5 to 5.0 mmol/L, the maximum removal efficiencies of MB and Cd2+ were obtained as 99.69% and 99.61%, respectively. The enrichment ratios were reduced from 24.34 to 7.65 for MB and from 22.01 to 3.35 for Cd2+. 相似文献
948.
PROBLEM: Many motorized countries use fixed penalties to deter the most common traffic violations. Fixed penalties are usually given at the spot by a police officer. If the offender accepts the fixed penalty, no court hearing or trial is held. During the years 1995-2004, the rates for fixed penalties for traffic offences in Norway increased substantially. This paper evaluates the effects on compliance of these increases. METHOD: Regression analysis was performed to determine the effects of increases in fixed penalties. RESULTS: For speeding in general, no effect of increasing fixed penalties can be found. For speeding close to speed camera sites, there is a weak tendency for the violation rate to go down. This tendency is not statistically significant at conventional levels. For seat belt wearing, wearing rates are found to increase as fixed penalties have increased. In recent years, however, enforcement of the seat belt law has stepped up, making it impossible to separate the effect of enforcement from that of fixed penalties. IMPACT ON INDUSTRY: It has been suggested that the police may adapt to stricter penalties by reducing enforcement or by adopting larger tolerance margins for violations. Available evidence does not support this hypothesis. 相似文献
949.
950.