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181.
Qinhua Fang Luoping Zhang Huasheng Hong Liyu Zhang Frances Bristow 《Environment, Development and Sustainability》2008,10(1):41-49
Environmental planning at different levels has been called for by environmental departments in China during last years to
integrate environment consideration to economic development. Based on the accomplished environmental planning practice in
Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps,
at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town
environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function
zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental
management and the decision-making. The experience shows that the ecological function zoning methods should be applied according
to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making
process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders.
Problems to be resolved in the future are also pointed out in the ending part. 相似文献
182.
《Journal of Manufacturing Processes》2014,16(1):86-92
The paper reviews the principles, benefits and limitations of the conventional short circuit transfer mode in GMA welding before describing the development and benefits of the controlled short circuit approach. Various options are described and an attempt is made to categorize the current commercial systems. 相似文献
183.
Susanne P. A. den Boer Jacobus J. Boomsma Boris Baer 《Behavioral ecology and sociobiology》2008,62(12):1843-1849
The seminal fluid that accompanies sperm in ejaculates has been shown or suggested to affect sperm competition and paternity
success of insects by preventing female remating, inducing oviposition, and forming mating plugs. In Atta leafcutter ants, queens have multiple mates but never remate later in life, although they may live and produce fertilized
eggs for several decades. The mating biology and life history of these ants therefore suggests that the major function of
seminal fluid is to maximize sperm viability during copulation, sperm transfer, and initial sperm storage. We tested this
hypothesis by comparing the viability of testis sperm and ejaculated sperm (mixed with seminal fluid) and found a significant
positive effect of seminal fluid on sperm viability. We further quantified this positive effect by adding accessory gland
secretion (a major component of seminal fluid) in a dilution series, to show that minute quantities of accessory gland secretion
achieve significant increases in sperm viability. Sperm stored by queens for 1 year benefited in a similar way from being
exposed to accessory gland compounds after dissection in control saline solution. Our results provide the first empirical
evidence that seminal fluid is important for the production of viable ejaculates and that the accessory glands of Atta males—despite their small size—are functional and produce a very potent secretion. 相似文献
184.
Nazario D. Ramírez‐Beltran Joan Manuel Castro Eric Harmsen Ramón Vásquez 《Journal of the American Water Resources Association》2008,44(4):847-865
Abstract: A practical methodology is proposed to estimate the three‐dimensional variability of soil moisture based on a stochastic transfer function model, which is an approximation of the Richard’s equation. Satellite, radar and in situ observations are the major sources of information to develop a model that represents the dynamic water content in the soil. The soil‐moisture observations were collected from 17 stations located in Puerto Rico (PR), and a sequential quadratic programming algorithm was used to estimate the parameters of the transfer function (TF) at each station. Soil texture information, terrain elevation, vegetation index, surface temperature, and accumulated rainfall for every grid cell were input into a self‐organized artificial neural network to identify similarities on terrain spatial variability and to determine the TF that best resembles the properties of a particular grid point. Soil moisture observed at 20 cm depth, soil texture, and cumulative rainfall were also used to train a feedforward artificial neural network to estimate soil moisture at 5, 10, 50, and 100 cm depth. A validation procedure was implemented to measure the horizontal and vertical estimation accuracy of soil moisture. Validation results from spatial and temporal variation of volumetric water content (vwc) showed that the proposed algorithm estimated soil moisture with a root mean squared error (RMSE) of 2.31% vwc, and the vertical profile shows a RMSE of 2.50% vwc. The algorithm estimates soil moisture in an hourly basis at 1 km spatial resolution, and up to 1 m depth, and was successfully applied under PR climate conditions. 相似文献
185.
Jason L. Huang 《组织行为杂志》2015,36(Z1):S53-S71
Modern work is frequently characterized by jobs where adaptive performance (AP) is crucial for employees to succeed in light of new or altered task demands. This recognition has fueled growing interest in AP as a dimension of workplace performance. To this point, however, research on AP has evolved from disparate perspectives and methods, resulting in fragmentation and a less than coherent knowledge base. This paper presents a comprehensive review of research studies regarding the nomological network of individual AP. In doing so, we synthesize the current knowledge base surrounding correlates of AP, elucidate current ambiguities, and suggest directions for future research efforts. We conclude that although the extant AP literature has amassed a critical body of studies linking various predictors to successful AP outcomes, much remains unknown, most critically regarding the implications of different methods of assessing AP, the effects of different types of changes in the task environment, the process of AP, and the steps organizations can take to foster AP among their employees. We hope that our synthesis and analysis paves the way for efforts to address these important questions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
186.
为了寻找能同时降低卷烟烟气中甲醛、乙醛、巴豆醛和颗粒物有害成分含量的离子交换树脂吸附材料,采用电镜扫描方法观察聚丙烯基阳离子树脂高分子功能材料的表面特征,应用压汞法分析其平均孔径、中值孔径、比孔容和比表面积,并测试了该材料的交换容量,采用环境试验舱检测法对比测试了该材料和活性炭降低卷烟烟气中甲醛、乙醛、巴豆醛和颗粒物有害成分含量的效果.结果表明,聚丙烯基高分子功能材料表面多斑点状突起,凹凸状明显,微孔和缝隙多,平均孔径为0.26 μm,中值孔径为149.3 μm,比孔容为19.23 cm3/g,比表面积为293.42 m2/g,交换容量为5.16 mmol/g,对烟气中甲醛、乙醛、巴豆醛和颗粒物的净化率分别达到79.6%、79.8%、82.8%和64.7%,而活性炭的净化率分别为20.3%、0、6.4%和54.2%.研究表明,该聚丙烯基高分子功能材料具有物理吸附和化学吸附性能,净化卷烟烟气中多种有害成分的效果明显优于活性炭. 相似文献
187.
为弥补现有地下工程围岩稳定性评价方法的不足,建立了改进的物元可拓模型。通过构造一种新的关联函数,解决了因传统的物元可拓模型的关联函数是一个分段函数而存在的不便于计算的缺陷,以及评价指标间的互不相容性问题,拓宽了物元可拓法的应用范围。将改进的物元可拓模型应用于某地下工程围岩的稳定性评价,结果表明,样本1、2、5属于Ⅱ级(较稳定),样本3、4属于Ⅰ级(稳定)。通过将其评价结果与传统可拓法及模糊数学综合评判结果进行比较分析,证明该评价方法的正确性。研究表明,改进的物元可拓模型的评价结果与实际工程地质情况更为吻合,准确度更高,能够反映各因素对围岩稳定性的影响,其合理性和可行性得到了验证。 相似文献
188.
新能源公交车是未来城市公交行业节能及温室气体减排的重点发展方向.新能源公交车在行驶阶段具有良好的节能及温室气体减排效果,而汽车制造、能源生产等相关生命周期阶段的能耗及温室气体排放常被忽视,且目前新能源公交车的乘客运载功能相对较弱,可能对节能及温室气体减排的潜力造成较为显著的影响.因此,本文基于北京市公交车的运营特征,采用生命周期评价(LCA)方法,选择客运周转量作为功能单位,核算了天然气公交车、混合动力公交车和纯电动公交车等新能源公交车相对于柴油公交车的节能及温室气体减排效益.结果表明:发展新能源公交车对促进北京市公交行业及城市节能低碳发展具有积极的作用,但相对于基于运营里程的核算结果,本研究新能源公交车节能及温室气体减排潜力均较低,主要原因是新能源公交车的实际载客量相对较低;混合动力公交车和纯电动公交车在空调开启时的节能潜力与温室气体减排潜力均远低于天然气公交车;通过发展情景分析,建议北京市现阶段应优先发展天然气公交车,适当发展纯电动公交车和混合动力公交车,以减少北京市公交车的总体能耗,同时降低温室气体排放强度. 相似文献
189.
A 1-dodecanethiol-based phase-transfer protocol is developed for the extraction of noble metal ions from aqueous solution to a hydrocarbon phase, which calls for first mixing the aqueous metal ion solution with an ethanolic solution of 1-dodecanethiol, and then extracting the coordination compounds formed between noble metal ions and 1-dodecanethiol into a non-polar organic solvent. A number of characterization techniques, including inductively coupled plasma atomic emission spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis demonstrate that this protocol could be applied to extract a wide variety of noble metal ions from water to dichloromethane with an efficiency of >96%, and has high selectivity for the separation of the noble metal ions from other transition metals. It is therefore an attractive alternative for the extraction of noble metals from water, soil, or waste printed circuit boards. 相似文献
190.