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71.
72.
Trace element compositions of 25 shards of Chinese Late Ming export blue-and-white porcelain from Zhangzhou and Jingdezhen kilns are analysed by Inductively Coupled Plasma Mass Spectrometry. Principle components analysis and REE distribution curves are used to establish method for provenance unknown Chinese export blue-and-white porcelain which may have originated from Zhangzhou or Jingdezhen kilns. By matching the REE distribution curves of Zhangzhou kiln samples and parent rocks of the possible clay sources used to make Zhangzhou blue-and-white, and comparing it with previous results of geological, geochemical and archaeological researches, the clay used for producing Zhangzhou export blue-and-white has been identified as having been collected from the weathered shells of a nearby potassium feldspar miarolitic granite outcrop. 相似文献
73.
Dendrochronological methods can be applied to the reconstruction of different types of environmental events such as climate changes, fires, glacier movements, floods, earthquakes, volcano activity. In the field of geomorphology dendrochronology is increasingly frequently used for the absolute dating of different types of mass-movements (rock falls, landslides and debris flows, etc.). Trees growing on slopes transformed by mass-movements are tilted and wounded while their stems and root systems are exposed or buried under sediment. These events are recorded in wood anatomy as eccentric growth, reaction wood, scar overgrowth by callous tissue, changes in cell size or adventitious root production. Dating changes in wood anatomy allows to date and precisely reconstruct the spatial and temporal occurrence of mass-movements with at least one year resolution. The paper provides a review of existing dendrochronological tools used in geomorphology and also an example of the application of eccentric tree-growth to reconstruct landsliding. Using tree-ring eccentricity allows to (1) obtain a dynamic depiction of slopes, (2) study landslide activity, not only contemporary, but also in the last tens of hundreds of years (depending on the stand age). 相似文献
74.
Danuta Michalska Anna Pazdur Justyna Czernik Małgorzata Szczepaniak Marta Żurakowska 《Geochronometria》2012,40(1):33-41
Lime mortars may contain carbon from different origins. If the mortars are made of totally burnt lime, radiocarbon dating yields the true age of building construction. The presence of carbonaceous aggregates gives the so-called dead carbon effect, which may generate older ages. Another source of carbon is charcoal present in mortars. An attempt has been made to apply the radiocarbon method to mortars of archaeologically estimated age from the Dead Sea region. Petrographical analyses of these samples show the carbonaceous character of the binder and large amounts of limestone aggregate. Determination of the mineral composition of the mortars and comparison with the geology of the surrounding, allows the provenance of the raw materials to be identified. They probably represent the Cretaceous rocks of the Judea Group. Separate radiocarbon dates were made on bulk mortar samples, binder, charcoal fragments and separated fractions from mortars. In the case of binder-aggregate mixture the reservoir effect correction has been applied. 相似文献
75.
2008年南京报恩寺阿育王塔出土了白木香和乳香两种北宋时期香料。本文梳理了南京报恩寺及阿育王塔的历史,通过文献说明了阿育王塔与宋代长干寺圣感舍利宝塔的关系;整理了我国古代典籍中对白木香和乳香的记载,考证出阿育王塔中的白木香乃沉香中的上品,乳香是印度的上品乳香-滴乳;探究了七宝阿育王塔中装藏白木香和乳香的缘由。最后,综合前人对现代白木香和乳香有效化学成分的分析结果,比较了阿育王塔出土白木香和乳香的有效化学成分。 相似文献
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77.
政治参与是政治学研究的重要命题,也是民主政治建设的重要内容。现阶段,公民政治参与在我国政治发展中居于十分重要的地位。作为我国新社会阶层重要组成部分的民族地区的新社会阶层,他们不仅是民族地区经济社会发展不可缺少的重要社会力量,也是推动民族地区政治发展的重要力量。目前,民族地区新社会阶层的政治参与还没有引起人们的足够重视,他们的政治参与权利还没有充分体现出来,还缺乏健全的法律制度保障。这种状况不仅不利于民族地区新社会阶层的自身发展,而且也不利于民族地区的稳定和健康发展。要重视民族地区新社会阶层合理的政治利益诉求,引导他们有序政治参与,从而把他们的活力和创造力整合、凝聚到社会主义现代化建设事业中来,为地区经济社会又好又快发展,为民族地区社会稳定和民族进步做出积极贡献。 相似文献
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79.
文化是一个民族的精神支柱。坚定不移地发展社会主义先进文化,在弘扬中华优秀传统文化的同时,创造出包括地域文化在内的中华文化新的辉煌,是新时期我国文化建设的重要任务。河湟文化作为青海东部黄河河谷地区和湟水流域具有明显地域特色的地域文化,在青海历史传承和未来发展中非常重要。研究河湟文化资源及其特点,做好河湟文化传承弘扬创新工作,是发展具有青海地域特色的社会主义先进文化的重要内容。 相似文献
80.
中国共产党的诞生,是近现代中国历史发展的必然产物,是中国人民在救亡图存斗争中顽强求索的必然产物。这种必然性,内在地反映了中国共产党的成立这一“开天辟地大事变”与辛亥革命这一“开启了中国前所未有的社会变革”间的关系。辛亥革命为中国共产党的成立准备了条件,即从一定意义上讲,它为中国共产党的成立奠定了阶级基础、思想基础、组织基础与政治基础。 相似文献