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1.
V. I. Roslikova 《Russian Journal of Pacific Geology》2008,2(4):370-376
The typification of ferromanganese nodules (FMN) formed in subaqueous and subaerial settings and in residual materials, as well as FMN localization in various sediments and soils, is discussed. The genetic diversity of morphologically similar FMN and the transformation of FMN-bearing complexes with changes in landscapes have been established. 相似文献
2.
离散裂隙渗流方法与裂隙化渗透介质建模 总被引:4,自引:1,他引:4
流体渗流模拟的连续介质方法通常适用于多孔地质体,并不一定适用于裂隙岩体,由于裂隙分布及其特征与孔隙差异较大。若流体渗流主要受裂隙的控制,对于一定尺寸的裂隙岩体,多孔介质假设则较难刻划裂隙岩体的渗流特征。离散裂隙渗流方法不但可直接用于模拟裂隙岩体非均质性和各向异性等渗流特征,而且可用其确定所研究的裂隙岩体典型单元体及其水力传导(渗透)张量大小。主要讨论了以下问题:(1)饱和裂隙介质中一般的离散流体渗流模拟;(2)裂隙岩体中的REV(典型单元体)及其水力传导(渗透)张量的确定;(3)利用离散裂隙网络流体渗流模型研究裂隙方向几何参数对水力传导系数和REV的影响;(4)在二维和三维离散裂隙流体渗流模型中对区域大裂隙和局部小裂隙的处理方法。调查结果显示离散裂隙流体渗流数学模型可用来评价不同尺度上的裂隙岩体的水力特征,以及裂隙方向对裂隙化岩体的水力特征有着不可忽视的影响。同时,局部小裂隙、区域大裂隙应当区别对待,以便据其所起的作用及水力特征,建立裂隙化岩体相应的流体渗流模型。 相似文献
3.
Liisa Rohweder 《GeoJournal》2004,60(2):175-181
Environmental education in business school context has a significant effect on the way companies view environmental problems.
Business schools train the future decision makers who can, with their own attitudes and practical actions, influence the contribution
of business to the process of ecologically sustainable development. However, several studies show that no systematic thinking
has been undertaken within business education as to what the educational prerequisites of the process of ecologically sustainable
development are. In this article, I will firstly analyze by means of environmental education how business polytechnics in
Finland have taken into consideration ecologically sustainable development. Secondly, I will raise the starting points for
the development of the implementation of environmental education as part of the business schools▪ educational plans. Integrating
environmental education into the vocational courses is identified as being one of the most effective ways of increasing the
effectiveness of environmental education. Thirdly, the emphasis is on identification of barriers of integrating environmental
education into the educational plans of business polytechnics. Theoretically, the article is attached to the objectives and
learning concepts of environmental education and to educational planning theory in general. The empirical data are based on
interviews I conducted 1999–2000 in all Finnish polytechnics offering business education. My article increases theoretical
and practical understanding of how environmental education should be implemented in business education and how the current
situation could be developed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Geography at elementary and middle schools in Louisiana, USA., remains a social studies strand along with civics, economics, and history, with no state-required geography course at any level. But because schools may require more geography than the state standard, this research examines the extent to which K–12 students are exposed to geography in Louisiana, using an electronic survey and an interview with state department of education officials. Results suggest that geography remains underemphasized, but the 2011 implementation of new social studies standards, the Advanced Placement Human Geography course, and other initiatives offer promise for more geographically literate Louisiana citizens. 相似文献
5.
以中小学生自然教育研学旅游作为具体情境,基于539份家长问卷数据阐释研学旅游动机与价值感知之间的关系,并通过成本感知和风险感知探讨其内在机制和边界条件。结果表明,家长感知的研学旅游动机越强烈,越容易感知到研学旅游产品所传递的价值,验证了研学旅游情境下动机对价值感知的积极影响,也形成了对动机与价值之间关系研究的理论补充。并且,这一动机除了直接作用于价值感知外,还会通过成本感知的部分中介作用影响价值感知,揭示了中国家长对于教育价值的重视会削弱其对“利失”的感知。此外,进一步验证了风险感知的积极影响,即家长感知研学旅游的不确定性水平越高,动机对价值感知的积极影响越明显,且会抑制成本感知对价值感知的负向作用,但风险感知水平达到一定高度时,其对成本感知与价值感知间的抑制作用将不显著。因此,面向需求设计打造产品,突出产品价值、加大宣传营销力度、把控活动安全、合理制定价格,获取家长群体的认同接受,将是研学旅游进一步拓展市场的重要考量。 相似文献
6.
Using an exploratory case study approach, this research used semi‐structured interviews to investigate the motivations, expectations and experiences of high school students in New Zealand who travelled to Cambodia on a school supervised field‐trip. Findings suggest students are motivated by altruistic behaviour and the desire for unique experiences. Students had very high expectations, predicting the experience to be either life changing or incredibly important. Post‐trip interviews revealed that the volunteer work undertaken was perceived as positive and that experiences of poverty were challenging and influential. Finally, personal development and an increased sense of social responsibility were identified as important effects of the trip. 相似文献
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10.
C18 O J = 2–1, C17 O J = 2–1 and [C I ] 3 P1 –3 P0 emission from the dense cold cloud B335 has been observed and modelled in order to determine the C/CO ratio. The observed ratio is compared with a prediction by Tarafdar who assumes a mechanism in which the CO dissociation is caused by photons of energy ∼ 13.8 eV. These were postulated by Sciama to result from the decay of dark matter neutrinos. Our value for the C/CO ratio sets an upper limit to the strength of the neutrino decay dissociation process, thus providing a significant datum for interstellar chemistry theory. 相似文献