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World-wide intercomparison runs has made possible the certification of two new Polish geological-environmental reference materials for multi-element trace analysis: Apatite Concentrate (CTA-AC-1) and Fine Fly Ash (CTA-FFA-1). "Recommended values' are established for 25 (CTA-AC-1) and 40 (CTA-FFA-1) elements respectively. In addition, "information values' are assigned for 12 elements in CTA-AC-1 and 10 elements in CTA-FFA-1. Our method of data evaluation has been further improved and a modified version of criteria for assigning recommended and information values is proposed.  相似文献   
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This report is a comment on two papers by Matese and Whitman (1989, 1992). We discuss here the applicability of uniform probability densities for the orbital parameters of the Oort cloud comets.  相似文献   
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Zeolite Na–X (FAU type) was synthesized from F-class fly ash in simple and economical way. Several months of storage of fly ash in NaOH solution, at room temperature, without any prior treatment, results in the production of material with ca. 50% content of Na–X zeolite. The most efficient reaction takes place at (OH) activity of 0.1–0.15 mol (OH)/g of ash and at S/L ratio of 33 to 67 g/dm3. Higher S/L value causes an accelerating dissolution–crystallization equilibrium attainment. Cl ion acts as the inhibitor of this reaction.  相似文献   
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Periglacial slope covers in the southern part of the Cracow Upland, S Poland can be grouped in five genetic categories: slope loess, washed loess, weathered debris, scree deposits, low-density flow deposits, and solifluctites or high-density flow deposits. They differ from each other with respect to their morphological position in relation to the slope, and in lithological characteristics. It was found that successive generations of slope deposits can be distinguished according to their degree of chemical weathering, which can be estimated on the basis of the presence and morphology of limestone clasts, on the content and colour of the colloid clay, and on the Fe2O3 and CaCO3 content of the clay particles.This paper contributes to a discussion on the possibility of palaeoclimate reconstruction based on slope deposits analyses.  相似文献   
5.
This report is a comment on two papers by Matese and Whitman (1989, 1992). We discuss here the applicability of uniform probability densities for the orbital parameters of the Oort cloud comets.  相似文献   
6.
The ongoing devolution of climate policy-making to sub-national levels has prompted growing interest in policy entrepreneurship by individuals who are politically and technically creative and institutionally resourceful. This paper investigates the case of the materials-management programme in the Oregon Department of Environmental Quality which has emerged as a national and international leader by focusing on the role of household consumption in greenhouse gas (GHG) emissions. Two noteworthy innovations involve the development of a consumption-based GHG emissions inventory and introduction of policies aimed at facilitating construction of small homes (so-called Accessory Dwelling Units, ADU). The case traces over several decades the higher order learning processes within the group and their entrepreneurship toward affecting broader changes in emission accounting and climate policies in Oregon. The paper identifies the enabling factors for these innovations, and considers: how to create the conditions for learning, experimentation, and policy entrepreneurship; how to reproduce these conditions in different locales; and how to recognize and foster innovations that arise outside the established mainstream ‘climate community’. It also stresses the benefits of breaking down the barriers between science-based analysis and policy. The two questions frequently raised in the climate policy debate – how to bring researchers and practitioners together to develop efficacious policies; and how to replicate successful programmes and policies across different communities, jurisdictions, and locations – should be re-examined. It may be more appropriate to ask instead: How to create conditions for learning, experimentation, and policy entrepreneurship; and how to reproduce these conditions in different locales.

Key policy insights

  • Using a consumption-based greenhouse gas emission inventory instead of a sector-based inventory radically changes climate policy priorities, shifting the emphasis from technological fixes to curbing household consumption.

  • Policy innovations thrive in teams that combine technical and scientific competencies with: a commitment to addressing societal problems; interest in inquiry, experimentation, and learning; entrepreneurship; and strategic and political savvy.

  • These qualities require breaking down artificial barriers between science and policy.

  • Transformative policy ideas can originate within institutional nodes that operate outside of an established community of expertise and authority; and these should be identified and fostered.

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Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of cropl...  相似文献   
9.
Being able to accurately locate and describe recreational use within marine parks is essential for their sustainable management. Given the difficulty in accessing many marine parks, as well as their large size, the surveys to obtain these much-needed data are often logistically challenging and expensive. Aerial surveys are one potential method for obtaining accurate, timely data and this paper details the design for one such survey conducted in the Ningaloo Marine Park, off the northwestern coast of Australia. Ningaloo has been nominated as a world heritage site and the fringing coral reef that forms the centrepiece of the Marine Park extends for 300 km along the coastline. The survey involved 34 temporally stratified flights conducted over a 12-month period. All vessels and people were geo-referenced and where possible, their activities were recorded, providing data that clearly illustrates dramatic expansions and contractions in recreational use. Not only does the spatial extent of use expand in the peak visitor season (April-October), the density of use correspondingly increases. High densities of recreational activity in the Park’s waters were accompanied by increased numbers of vehicles, camps, boat trailers and boats on the adjacent shoreline. Aerial surveys proved to be an effective method for rapidly obtaining recreational data with high spatial accuracy. Such a method has broad applicability to marine parks as it provides comprehensive data to benchmark existing recreational use, as well as monitor future changes in activity patterns, which are essential for the informed management that must underpin sustainability efforts.  相似文献   
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