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941.
942.
本文报道 NMF-1防霉剂的合成,理化数据,毒性检测,防腐蚀和抗微生物试验以及对纸张、纺织品性能、色彩的测试.该防霉剂有防霉杀虫片、防霉浆糊添加剂、防霉防虫乳剂以及溶刺型防霉防虫液,不仅适用于文物、图书、档案的防霉,而且在其它领域亦能得到广泛的应用. 相似文献
943.
944.
本文主要论述了夏朝至战国时期中国古代城的形成与发展,说明中国古代城的形态规模与分布位置是与自然环境和社会条件密切相关的。城的形态受地理环境影响较明显,城的规模与生产力发展水平及城的行政等级有关,而城的分布位置主要是与国家的统治与稳固、城的经济发展等因素有关。文章最后还论述了遥感技术在探测古代城的形态规模与分布位置方面的应用和方法。 相似文献
945.
Tania Murray Li 《Development and change》1996,27(3):501-527
This article argues that divergent images of community result not from inadequate knowledge or confusion of purpose, but from the location of discourse and action in the context of specific struggles and dilemmas. It supports the view that ‘struggles over resources’ are also ‘struggles over meaning’. It demonstrates the ways in which contests over the distribution of property are articulated in terms of competing representations of community at a range of levels and sites. It suggests that, through the exercise of ‘practical political economy’, particular representations of community can be used strategically to strengthen the property claims of potentially disadvantaged groups. In the policy arena, advocates for ‘community based resource management’ have represented communities as sites of consensus and sustain-ability. Though idealized, such representations have provided a vocabulary with which to defend the rights of communities vis-à-vis states. Poor farmers, development planners, consultants and academics can also use representations of community strategically to achieve positive effects, or at least to mitigate negative ones. Most, but not all, of the illustrations in this article are drawn from Indonesia, with special reference to Central Sulawesi. 相似文献
946.
初版与再版邮票的质子激发X荧光鉴别法 总被引:1,自引:0,他引:1
报道用质子激发X荧光(PIXE)法分析我国初版与再版纪念邮票和特种邮票的实验结果。实验表明,初版和再版邮票所用印刷油墨颜料的化学元素的成分是不同的,因而PIXE方法可以用来实现初版和再版珍贵邮票的无损鉴定。这一方法也可以应用到对某些重要纸质文献或艺术品真伪的鉴定。 相似文献
947.
本文以鸭子口1991年入境车辆与旅客为例,分析了神农架自然保护区入区车辆与旅客组成及季节变化情况,并对游客客源及车源作了初步研究。以期对神农架的自然保护和旅游资源开发提供客观依据。 相似文献
948.
Bo Wu Weijuan Zhao Hong Zhao Xiao Ren Xiaomin Liu Bin Zhang Bo Li Dan Zhao 《Archaeometry》2023,65(2):247-258
The development of Chinese ceramics culminated during the Song dynasty. At this time, exquisite celadon works emerged, such as Ru Guan celadon and Southern Song dynasty official kiln celadon, which exhibited the glory of their era. Since the excavation of Zhanggongxiang kiln celadon in Ruzhou city, Henan province, China, it has been attracting widespread scholarly attention at home and abroad. Most scholars have suggested that Zhanggongxiang is the official kiln of the Northern Song dynasty. In this paper, taking the celadon unearthed from the Zhanggongxiang kiln as a sample, the combination of laser Raman spectrum and thermal expansion methods is used to study the inheritance relationship between Zhanggongxiang celadon and Ru Guan celadon in the firing process. Meanwhile, the rationality of using Raman Ip value to evaluate the firing temperature of ceramics is reviewed. The main conclusions are as follows. First, the firing temperature of Zhanggongxiang celadon with various glaze colours is quite different, whereas the firing temperature of the same glaze colour is similar, thereby inheriting the firing technology of Ru Guan porcelain. Second, the Ip value of glaze cannot evaluate the firing temperature of porcelain with similar firing temperature. The Ip value corresponds to a range, within which it does not fully conform to the rule that the larger the Ip value, the higher the firing temperature. The Ip value is also associated with the formulation in addition to firing temperature. It is applicable to evaluating porcelains with a similar formulation but a large temperature difference. 相似文献
949.
In the present study, we analyzed seven wooden bows and 13 arrows excavated from the cemeteries of Subeixi Culture (13th century BCE–AD second century) in the Turpan Basin, northwest China. A total of six taxa, viz. Morus sp., Salix sp., Picea sp., Lonicera sp., Betula sp., and Tamarix sp. were identified. Some of these taxa have been generally accepted to be suitable for bow-and-arrow production. All these taxa were local in origin but distributed in different ecotonal zones, including oases, saline-alkali lands, and mountain areas. Previous archaeological studies have confirmed that the Subeixi populations lived an agro-pastoral life. By analyzing the possible provenance of these wood samples, it can be hypothesized that these ancient agro-pastoralists moved between the Turpan Basin and the Tianshan Mountains on a seasonal basis. 相似文献
950.
In the last three decades, China has taken actions to tackle its environmental issues while the tension between policymakers at the central level and decentralized implementation of such policies has been a major concern. This study investigates how policy clarity and high powered incentive system jointly affect organizational performance in the context of environmental governance in China. Utilizing city-level data compiled with text data extracted from Report on the Work of the Government from 2004 to 2015 and Difference in Differences (DID) design, we find that the compliance of local officials to protect the environment as well as the actual environmental protection outcome significantly increased. Our study also finds evidence that newly-appointed Party Secretaries at the city level are the main facilitators of enhancing environmental regulation policies. This research proposes a two by two typology based on the principal-agent theory explaining how successful environmental governance within this period in China is realized and offers practical implications for those who seek to enhance the effectiveness of environmental governance. 相似文献