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991.
在多年自然营力作用下,有些古建筑的砖体正遭受着严重的风化破坏,亟需修复和加固。为此,通过试验,研究烧制温度对红砖物理力学性质的影响,以期为古建筑修复和保护提供理论参考。利用模具手工制作边长为5 cm的立方体黏土砖。利用高温炉分别在700、800、900、1 000和1 100℃的温度下烧制成红砖。然后,测试不同烧制温度下红砖的块体密度、颗粒密度、开孔孔隙率、总孔隙率、常压吸水率、饱和吸水率、毛细吸水系数、纵波波速、孔径分布、单轴抗压强度。结果表明,烧制温度会影响物理力学性质,但物理力学性质并非随着烧制温度的增加而改善。烧制温度为1 100℃时砖的性能最优,烧制温度为800℃和900℃时砖的性能中等,烧制温度为700℃和1 000℃时砖的性能差。本文分析了烧制温度为1 000℃时红砖的物理力学性质差的原因。研究结果可为古建筑修复和保护提供理论参考。 相似文献
992.
Anchi Hoh 《Domes : digest of Middle East studies》2019,28(2):241-276
China's Belt and Road Initiative (BRI) aims at connecting the continents of Asia, Europe, and Africa through a combination of infrastructure projects and soft‐power programs. All of the six land bridges and maritime routes under the BRI extend westward, mostly passing through Central Asia and the Middle East on land or by sea. Cooperation with countries in these regions will, according to China's design, meet its domestic energy needs, and grow the country's economy. China recognizes, however, that in Central Asia and the Middle East, the risks posed by what it calls the “Three Evils” — terrorism, extremism, and separatism can impact the success of the BRI. They can also impact stability in its own adjacent areas, including Xinjiang. Therefore, in concert with the BRI, China is also identifying and deploying bilateral and multilateral diplomatic mechanisms aimed at security coordination with BRI countries in these two volatile regions. This article provides an overview of BRI developments in the two regions and examines some of the diplomatic mechanisms China is using to coordinate security and reduce risks. 相似文献
993.
中国大城市旅游休闲业态的空间格局研究:西安案例 总被引:1,自引:0,他引:1
明确大城市旅游休闲业态的分布规律对于提高大城市旅游休闲要素配置效率及完善城市现代服务业体系具有重要意义。本文以机构兴趣点(POI)数据为基础,利用最邻近距离指数、核密度估计及地理探测器等空间分析方法,以西安市为案例探究中国大城市旅游休闲业态空间格局的规律性。结果表明,西安城市旅游休闲总体业态和细分业态均表现为在城市中心局部多核集聚,且业态密度由城市中心区向边缘区梯度递减的分布结构。而这一规律实则为消费市场、CBD区位、经济水平和路网密度等因素综合作用的结果。文章认为,为提高大城市旅游休闲产业要素配置的均衡性与高效性,城市管理者需兼顾城市中心及外围区域的统筹发展,并应在消费引导、资本投入、功能区建设和基础设施优化方面加大对外围区域的支持力度。 相似文献
994.
Weiying Peng 《International Journal of Cultural Policy》2019,25(7):904-916
ABSTRACTThis paper looks at China’s soft power strategy in relation to the film industry, which since the early 2000s has opened to international co-productions and investment. Despite many coproduction projects being endorsed by government, results have not added significantly to China’s film-making reputation. The paper shows that coproductions have a diplomatic function, which implies a more conventional understanding of soft power. The paper also considers the tension between artistic freedom and censorship that impacts on all coproduction projects in China and which undermines the efficacy of China’s soft power strategy. The paper advances the proposition that coproduction with countries in Eurasia under the cultural template of the Belt and Road Initiative might present new opportunities to blend China’s stories into a narrative of shared prosperity. In doing this, the advance of China’s economic power is supported by cultural policies that evoke a historical past as much as a shared future. 相似文献
995.
John Holmes 《Geographical Research》2019,57(3):312-330
The concept of path dependence is central to the current discourse on evolutionary approaches in regional transformations. Along the subtropical coastlands of eastern Australia, low‐input, low‐income, and labour‐intensive dairy farms were subject to prolonged dysfunction. Their creation and entrenchment serve as a potent case study of path dependence and lock‐in that were driven by mutually reinforcing attributes—behavioural, socio‐economic, cultural, political, and infrastructural. Functional rigidification and incipient dissolution were scrutinised in farm surveys undertaken from 1952 to 1954 in the Moruya and Copmanhurst districts of coastal New South Wales. At both locales, the dairy industry comprised a core of long‐term stable producers located mainly on the more accessible and productive alluvial soils, together with a fluctuating number of marginal producers motivated by a variable mix of personal, locational, and temporal influences. The demise of dairying was prolonged, in part by the industry's exceptional survival capabilities and in part by the lack of any viable alternative farming staple. The belated collapse of dairy farming in the 1960s and 1970s has facilitated the emergence and lock‐in of an alternative multifunctional pathway, driven primarily by consumption with subordinate production and protection values. The two case studies reveal synergies between the closely aligned path dependence and the multifunctional trajectory/transition concepts in yielding insights into the dynamics of rural change and in offering guidelines for further research within evolutionary economic geography. 相似文献
996.
Chronic non‐communicable diseases comprise a major challenge for health in contemporary Australia and across the globe and, while various factors are at play, personal choices in behaviour and lifestyle are significant. The physical make‐up and ongoing management of the places where we live positively and negatively influences these lifestyle choices and subsequent health outcomes. However, responses—in research, policy, built environment design, construction, and management—frequently fail to recognise the intricacies of this people‐place‐behaviour nexus largely because those responses are highly focused and empirical. Rather, the health‐supportive environments needed to address the current chronic disease epidemic also require additional—networked, nuanced, and intuitive—understandings. Responding to that need, the study described in this paper took a comprehensive view of what constitutes a health‐supportive built environment. We detail the composite methods employed—built environment audits, interviews, and focus groups—all of which are available for use by others in similar situations. Then, using two case study examples, we reflect upon how our methodology revealed otherwise hidden aspects of the extent to which the study sites supported or hindered health‐supportive behaviours and responses. These results suggest intervention actions for policy makers and practitioners that will help them respond to the complex needs of communities in creating a health‐supportive environment. 相似文献
997.
Denis Clark 《Nations & Nationalism》2019,25(4):1362-1385
One of the most important questions at the 1919 Paris Peace Conference was what to do about the newly re‐created state of Poland. The Paris peacemakers realised the importance of the settlement, thanks in part to dire warnings about Poland's future, and the leaders spent much time discussing the territorial settlement. Yet discussions of this important question regularly strayed from debates about policy to incorporate understandings of Polish national character. In particular, the leaders of the so‐called Big Three, Britain, France, and the United States, connected expert opinion and the broader political landscape to stereotyped understandings of national character, among other factors. With reference to scholarship on stereotyping, this article analyses how developing attitudes on Polish national character became integrated into the complex settlement of Poland's borders. The peacemakers' decisions, which were a compromise between different points of view, reflected interconnected understandings of the Polish settlement. 相似文献
998.
M. Boi 《Archaeometry》2017,59(2):316-330
This study proposes an alternative interpretation of the pollen grains found on the Christian relic of the Shroud of Turin, the majority of which belong to entomogamous plants. The examination of the images in the literature and the observation of modern pollen under light microscopy and scanning electron microscopy reveal that the most abundant pollen on the relic may be attributed to the genus Helichrysum (Asteraceae family) instead of Gundelia tournefortii. The other most important pollen found belongs to the Cistaceae‐Cistus spp.—the Apiaceae—probably Ferula spp.—and the Anacardianceae—the genus Pistacia. These pollen grains could have come from plants used to obtain expensive and valuable substances that would have been the basis for the oils of Helichrysum, ladanum and galbanum, as well as for mastic and terebinth products; this fact has not been considered by previous authors. Ancient historical records give us references that could link the pollen traces to a mixture of balms and ointments employed for preparing the body for funeral and burial. For this reason, the palynological study reveals coherency with these historical records about the rituals, as reported on by the important scientists Pliny the Elder and Dioscorides, dating back to the first century ad . 相似文献
999.
New Insights into the Provenance of the Obsidian Fragments of the Island of Ustica (Palermo,Sicily)
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F. Foresta Martin A. Di Piazza C. D'Oriano M. L. Carapezza A. Paonita S. G. Rotolo L. Sagnotti 《Archaeometry》2017,59(3):435-454
In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA–ICP–MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri‐Tyrrhenian area during the prehistoric age. 相似文献
1000.
Full‐Vector Archaeomagnetic Dating of a Medieval Limekiln at Pinilla Del Valle Site (Madrid,Spain)
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Á. Carrancho A. Goguitchaichvili J. Morales J. A. Espinosa‐Soto J. J. Villalaín J. L. Arsuaga E. Baquedano A. Pérez‐González 《Archaeometry》2017,59(2):373-394
Archaeomagnetic dating based on the full geomagnetic field vector was carried out on a limekiln excavated at Pinilla del Valle archaeological site (Madrid, Spain). The limekiln tradition in this area is largely documented by historical sources for recent centuries but the date of the studied kiln's last use was unknown. The combination of mean archaeomagnetic directional and absolute archaeointensity results shows that the kiln was last used between ad 1296 and 1413, in good agreement with two independent radiocarbon dates. This study provides the first archaeomagnetic evidence that the local limekiln tradition dates back to at least late medieval times. Furthermore, the inclusion of these data in the Iberian secular variation curve and geomagnetic field models will help to improve the archaeomagnetic dating technique. 相似文献