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31.
The quantitative analysis of glass, ceramics and related silicate systems by means of energy dispersive X-ray fluorescence spectrometry is considered and problems arising from the selective absorption of X-rays in multi-element specimens are discussed. A computer programme written in FORTRAN and based upon a “semi-fundamental parameters” approach to the correction of matrix effects in glass and chemically similar materials is fully described. Model data are provided to enable the programme to be run and tested. An “empirical coefficients” computer programme for the quantitative analysis of silicate systems is outlined and the limitations of this type of programme are pointed out. The importance of adequate sample preparation prior to X-ray spectrometric analysis is stressed. 相似文献
32.
南唐方镇在许多方面都发生了重要变化,这些变化引发了方镇体制军事特质的丧失,因此南唐方镇的体制实际上已不再是原先的军政体制,而是一种新的民政体制。决定南唐方镇体制崩解的根本因素是安定战略。五代十国时期是一个特别值得重视的在政治体制方面发生变化的关键时期。 相似文献
33.
Marcia Siqueira Rapini Tulio Chiarini Alexandre de Queiroz Stein 《Journal of regional science》2024,64(1):108-135
The purpose of this paper is to spatially and regionally examine academic engagement within Brazil, identifying patterns. Moreover, our investigation can contribute to a better understanding of how knowledge can be turned into a tool to fight regional inequality. We depart from two hypotheses: first, universities situated in peripheral regions interact more with companies from relatively more dynamic regions, and second, in the absence of industrial knowledge demand, universities tend to collaborate more closely with a diverse range of stakeholders in the region. To evaluate these hypotheses and find empirical evidence, we consider 4497 research groups and 4603 nonacademic organizations as “nodes” connected by 8830 collaborations throughout all Brazilian regions. Social network tools are used to illustrate the spatial and regional dimensions of academic engagement more accurately. The results show that academic engagement is not regionally homogeneous, demonstrating essential differences regarding local nonacademic partnerships. Innovation policies, which encourage only university–firm interactions, perpetuate regional inequality. 相似文献
34.
ABSTRACTThis paper takes an interdisciplinary perspective to focus on the role played by the rural-urban dual system in China’s urbanization and migration. We explain its establishment in China in the 1950s and its genealogy in the industrialization strategy adopted in the USSR in the late 1920s and early 1930s. In the reform era, the system has been refashioned to suit a new set of demands of the state industrialization strategy to cater for the global economy. We analyze the mechanisms of the dual system, and how it has helped generate low-cost migrant labor for urban employers and siphon off revenues for urban governments by expropriating rural land. We also argue that there are fundamental differences between the dual system and the common “dualism,” based on the Lewis dual-sector model, as observed in many developing countries. The plight of children of migrants is used to illustrate the main points made in the paper. Our research challenges the prevailing perspectives in Chinese geography and urban studies, many of which are based on market-driven neoclassical economics or global neoliberalism, often ignoring China’s historical and institutional contexts. 相似文献
35.
Simon Dalby 《The Canadian geographer》2019,63(1):100-111
Considering recent formulations of geopolitical culture in combination with concerns that environmental change be included in contemporary geopolitical analysis, this paper examines the implicit geopolitical formulations in recent Canadian federal political discourse both in Stephen Harper's Conservative government and the subsequent Liberal administration. Contrasting earth system science ideas about global transformations with Canadian nationalist rhetoric concerning petroleum production and notions of unlimited resource extraction as parts of national identity sharply highlights the contours of Canadian identity. If sustainability is to be taken seriously, the official nationalist formulation will have to be drastically changed, but as the widespread rejection of the LEAP manifesto suggests, such ideas of a sustainable mode of globalization have yet to substantially influence Canadian political discourse, despite the rhetorical support offered to the Paris Agreement on Climate Change by the Liberal government of Justin Trudeau. 相似文献
36.
Bart Sleutjes Jeroen Ooijevaar Helga A.G. de Valk 《Tijdschrift voor economische en sociale geografie = Journal of economic and social geography = Revue de géographie économique et humaine = Zeitschrift für ?konomische und soziale Geographie = Revista de geografía económica y social》2019,110(3):359-377
This paper studies residential segregation in the Amsterdam Metropolitan Area and makes three contributions to the recent debates on segregation. First, both ethnic and socio‐economic segregation are studied by comparing isolation index scores for both individual indicators and their interactions. Second, neighbourhoods are defined as scalable individualised units, which allows for comparisons across spatial scales. Third, the paper adopts a longitudinal approach by covering three different time points, which enables us to get a grip on segregation trends. The results indicate that there are notable differences in segregation levels and trends between the applied segregation indicators. Ethnic segregation remained largely stable over the 2003–14 period, whereas the indicators of socio‐economic segregation have slightly changed, but all in different directions. Only for tertiary education segregation has increased over the entire period. The Dutch welfare system, the well‐dispersed and socially‐mixed social housing sector and gentrification help to explain these developments. 相似文献
37.
Lulu Zhang Jingjing Zang Yuhong Wang Liguang Sun 《Interdisciplinary science reviews : ISR》2019,44(3-4):387-401
ABSTRACTAlong with its modernization process, China has developed many interests in polar ecology and has connected the significance of the Antarctic and Arctic to its national interests. We present an in-depth analysis and assessment of the state of the art of China’s polar research from following points of view, mechanism of policy making on polar affairs, science diplomacy and polar governance, on-spot research expedition management, allocation of scientific funds, forming polar scientific team, especially on the management system of CHINARE. From an integrated perspective of social and natural sciences, we present a vision for future reform and development of polar affairs of China: to establish a macro and long term policy for the polar regions, to promote and establish a government-led, diversified polar scientific management system, to establish a reasonable and rule based evaluation system, to train, stabilize and expand polar scientific research teams, and to attract and encourage talents for polar science communication. 相似文献
38.
Teemu Makkonen Adi Weidenfeld Allan M. Williams 《Tijdschrift voor economische en sociale geografie = Journal of economic and social geography = Revue de géographie économique et humaine = Zeitschrift für ?konomische und soziale Geographie = Revista de geografía económica y social》2017,108(6):805-820
The importance of inter‐regional co‐operation and innovation are widely accepted in the development rhetoric of the European Union. The highlighted importance of both themes in the context of borderlands has recently led to the coining of a new concept, cross‐border regional innovation system. However, little attention has been given to the empirical analysis of the concept. This paper suggests a framework for empirically validating the concept by examining the levels of integration between cross‐border regions. The outcome is a proposed framework that can be operationalised by measurable indicators of cross‐border co‐operation in a regional innovation system setting. The framework was further tested with illustrative empirical cases that demonstrate its feasibility. 相似文献
39.
The entrepreneurial ecosystem (EE) literature has attracted much attention, especially in policy circles. However, the concept suffers from a number of shortcomings: (1) it lacks a clear analytical framework that makes explicit what is cause and what is effect in an EE; (2) while being a systemic concept, the EE has not yet fully exploited insights from network theory, and it is not always clear in what way the proposed elements are connected in an EE; (3) it remains a challenge what institutions (and at what spatial scale) impact on the structure and performance of EE; (4) studies have often focused on the EE in single regions or clusters, but lack a comparative and multi-scalar perspective and (5) the EE literature tends to provide a static framework taking a snapshot of EE without considering systematically their evolution over time. For each of these shortcomings, we make a number of suggestions to take up in future research on EE. 相似文献
40.
Nigel Walford 《Journal of Geography in Higher Education》2017,41(3):310-326
The arrival of the term Geographical Information System (GIS) in the 1960s soon created a demand for training and education in the use of this specialist hardware and software. Initially the main focus was on training people to use GIS, formal named degree programmes leading to postgraduate and undergraduate qualifications arrived later. This paper explores the changing landscape of U.K. degree level GIS education drawing on contemporary information from Higher Education Institution websites and a case study of the first single honours degree in GIS in Europe. The paper identifies a rise and fall in the number of named undergraduate “GIS” degrees since the late 1980s sandwiched between the continuation and development of postgraduate qualifications. In parallel with this trend the teaching and learning of GIS skills has emerged as a core component of undergraduate degree programmes with “Geography” in their title and in national school and degree level benchmarking statements for the discipline. 相似文献