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141.
内容依托教学(CBI)是融语言学习与内容学习为一体的教学方式。在高职商务英语专业采用CBI教学模式,以真实的商务活动为背景,使语言学习和专业技能的培养与商务实践相结合,有助于形成"懂商务、会英语"的复合型应用人才培养模式。但目前CBI的实施还面临着教师素质、教学效果以及评估体系等方面的问题,可通过培养专业师资、制定合理教学进度等方法逐步完善。  相似文献   
142.
Pihlajamäki M  Tynkkynen N 《Ambio》2011,40(2):191-199
This article examines the views of scientists on intricacies of scientific knowledge that affect science–policy interface in the Baltic Sea eutrophication governance in Finland. The analysis demonstrates that these intricacies can be divided into five categories: (1) uncertainty of knowledge concerning ecological processes, (2) heterogeneity of knowledge, (3) societal and political call for (certain) knowledge, (4) contingency of the knowledge that ends up taken as a baseline for decision making and further research, and (5) linkages of knowledge production, processing, and communication to particular characteristics of individual researchers and research societies. By explicating these aspects, this article illustrates the ways in which scientific knowledge concerning eutrophication is human-bound and susceptible to interpretation, thus adding on to the uncertainty of the Baltic Sea environmental governance. The aim is, then, to open up perspectives on how ambiguities related to science–policy interface could be coped with.  相似文献   
143.
Land Degradation on Barren Hills: A Case Study in Northeast Vietnam   总被引:4,自引:0,他引:4  
The term "barren hills" has been a keyword for land degradation in the uplands of Vietnam for over a decade. Nevertheless, the "barren" land is still not adequately ecologically characterized. In this work, we analyze land use-induced changes in vegetation and soil properties along a sequence of barren hills types formed on one physiotope. The study is undertaken in the Bac Kan province, one of the poorest upland regions where livestock plays an important role. A transition from an old-growth laurel forest to a sparse manmade grassland is characterized by a total of 177 species, rapid species turnover, and discrete dominants, and an overwhelming effect of disturbance history on both soil and vegetation patterning. Land degradation is most apparent in land use-induced maintenance of arrested successions, and the regeneration course is shifted towards drier formations. We hypothesize a conceptual model as an aid to understanding the process of early fallow differentiation in response to the patterned, fine-scale disturbances. The larger-scale implications of the observed trends in regeneration potentials deviation, and, in particular, the effect of water buffaloes in halting fallow successions, are discussed.  相似文献   
144.
采用氯化锌活化法制得核桃果皮基活性炭吸附甲基橙和酸性品红,考察了吸附时间,p H,吸附质初始浓度对吸附性能的影响及吸附热力学和动力学性质。结果表明,核桃果皮基活性炭是吸附甲基橙和酸性品红染料的理想材料;延长吸附时间,去除率和吸附量增加,最佳吸附时间为6 h;减小p H值,去除率和吸附量增加。p H为6时,2种染料的去除率达95%以上,吸附效果较好;增大吸附质初始浓度,去除率降低,吸附量增大,当甲基橙初始浓度为180 mg/L时,吸附基本达到饱和;甲基橙的吸附属于单层吸附,酸性品红的吸附属于多层吸附行为。准二级动力学方程均能较好地解释2种染料的吸附动力学行为。  相似文献   
145.
This article focuses on the governing system of the mitigation of eutrophication in the Baltic Sea. Policies and measures of the Baltic Sea coastal countries, the macro--regional (HELCOM) level, and the level of the European Union are described and governance challenges explicated. We found that the main challenges at different governance levels include: differences between coastal countries in terms of environmental conditions including environmental awareness, overlaps of policies between different levels, the lack of adequate spatial and temporal specification of policies, and the lack of policy integration. To help to meet these challenges, we suggest closer involvement of stakeholders and the public, the improvement of the interplay of institutions, and the introduction of a “primus motor” for the governance of the mitigation of eutrophication in the Baltic Sea.  相似文献   
146.
Circulation and Stream Plume Modeling in Conesus Lake   总被引:1,自引:0,他引:1  
A three-dimensional hydrodynamic model that includes the effect of drag from macrophytes was applied to Conesus Lake to study the seasonal circulation and thermal structure during spring and early summer. Local weather conditions and stream flow data were used to drive the model. The drag coefficient for macrophytes was calculated as a function of leaf density. In general, the model results show good agreements with the observations, including vertical temperature profiles measured at two locations and average surface temperature derived from calibrated thermal imagery for large-scale simulations of the entire lake. Additional high-resolution simulations were carried out to understand water circulation and transport of sediment and model-generated tracer during hydrometeorological events at stream mouths for two experimental sites. The model results show that the plume development at stream mouths during storm events in Conesus Lake are site-dependent and may either be current- or wind-driven. The results also show a significant effect from the presence of macrophytes on sediment deposition near stream mouths.  相似文献   
147.
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149.
内容依托教学是内容学习和语言学习为一体的教学方式,此种教学方法在高职商务英语专业教学中的应用效果卓著。通过观察和访谈收集相关数据,采用定性的研究范式,发现在内容依托教学的初步实施阶段还存在学生的认识态度、相关课程的教学内容以及测试和评估等方面的问题。  相似文献   
150.

Background, aim and scope  

Salt efflorescences markedly contribute to the alteration and deterioration of building material, in this case the Villamayor Sandstone of the facades in the Old Town of Salamanca, Spain (United Nations Educational, Scientific and Cultural Organization world cultural heritage site). A better understanding of the mechanisms of salt formation and the involved elements would allow more precise measures in monument conservation. The magnesium which is required for the salt precipitation originates from selective processes of hydrolysis. The source of sulphate, however, is presently not as clear. Identifying the source of the sulphur was the main goal of this research. Isotope ratio measurement of δ34S and δ18O was used to clarify the origins of Mg sulphate salts.  相似文献   
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