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This paper discusses studies of the development of river conservancy in modern China, and the role of engineers-in-chief in river improvement planning on rivers such as the Hai-ho (Haihe) and the Whangpoo (Huangpu). It discusses the introduction of foreign hydraulic dredging technology and management into two major Chinese ports. It then analyses the process by which two agencies of the Chinese government absorbed and adjusted this technology to suit local circumstances in the treaty ports of Tianjin and Shanghai beginning in the 1890s. Without prior experience in river conservancy, the conservancy boards adopted a range of foreign technologies. This allowed them to develop into major institutions that facilitated increasing trade flows between China and the rest of the world. Of particular significance in this process of technological change was the role of the expatriate engineers-in-chief who were employed as chief executive officers of both agencies. They were responsible for establishing the operations of the agencies, accommodating an increasing range of responsibilities such as financial and human resource management, and training Chinese engineers and managers for senior positions until they were ready to replace the expatriate engineers-in-chief after the 1930s. 相似文献
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采用木材制作的藏展空间,木材释放出的挥发性有机酸,在一定的温湿度条件下,会对文物造成不良的影响,因此需要建立一套对木材挥发性有机酸测定的方法.为此,采用固相微萃取(SPME)样品预处理技术,分离富集木材中的挥发性有机物,结合气相色谱-质谱(GC/MS)联用技术对木材中挥发性有机酸进行半定量分析,研究了9种木材中挥发性有机酸的挥发量和分布规律.结果表明,不同木材有机酸的挥发量差别较大.实验结果可为博物馆在装修和储藏中对材料的筛选提供科学依据. 相似文献
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为改善Oddy测试法实验周期长,依靠目测判断腐蚀程度的状况研究建立了一种薄膜试片测试法,研发薄膜试片、设计成套测试容器与夹具、改变测试条件并结合数码采集腐蚀图像和对腐蚀图像数字化分析等简化藏展材料评估筛选实验操作、缩短测试时间和提高结果分级判别能力.另外,固相微萃取和气质联用仪(SPME-GC/MS)被用于表征藏展材料在挥发和降解过程中所释放的污染物成分,佐证其对银、铜和铅金属文物的潜在危害.新建薄膜试片测试法表明,14d的测试周期不仅大大缩短了测试时间,简化了操作,而且薄膜试片的使用也有利于克服人为分级的主观判断性,为数字化分级打下坚实基础. 相似文献
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无酸纸的发展及其在文物保护中的应用 总被引:1,自引:0,他引:1
无酸纸是很重要的一种馆藏文物保护载体.本文对无酸纸的发展现状及在文物保护中的应用进行了总结.同时指出,根据我国文物保护的需要,研制文物保护专用无酸纸并建立相关的评价标准是无酸纸的发展趋势. 相似文献
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博物馆文物环境因装饰材料所致甲醛污染以及由此产生对文物危害问题已被普遍关注.为了评价净化材料实际使用中对污染物去除净化能力,搭建了静态试验舱,建立了该环境中甲醛的定量分析方法.研究了甲醛溶液法和人造板散发法两种产生甲醛气体的方法,以及吸附材料不同加入方法等对净化材料评价结果的影响,研究试验舱内甲醛浓度随时间的变化规律,建立了净化材料脱附量检测方法,分别测定了活性炭和三种壳聚糖基净化材料的净化效果.结果表明,用人造板散发法产生甲醛气体方法能用于甲醛净化材料的评价,得到净化率指标反映了净化材料在实际文物环境中的应用效果,脱附量指标能直观比对和反映净化材料对污染物的吸附稳定性. 相似文献
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Construction of a quartz OSL standardised growth curve (SGC) for aeolian samples from the Horqin dunefield in northeastern China 总被引:1,自引:0,他引:1
It has been suggested that the standardised growth curve (SGC) method can be used to de-terminate De accurately and reduce the measurement time. However, different opinions regarding the applicability of the SGC method exist.
In this paper, we report the construction of quartz OSL SGC for 35 aeolian samples from different parts of the Horqin dunefield
in northeastern China, and then test their applicability for De determination. Our results suggest that: 1) up to a regeneration dose of 80 Gy, the SGC of the Horqin dunefield can be fitted
using the exponential plus linear equation, with the r2 value of 0.97, and all the regeneration dose points closely stick to the fitting line, implying that all samples share a
very similar dose-response curve; 2) for samples with Des ranging from 1 to 50 Gy, the ratios of SAR De to SGC De fall within the range of 0.9–1.1, and the average ratio of SAR De to SGC De is 1.01±0.01, close to unity. Therefore, the construction of SGC is correct, and the SGC is an effective procedure for accurate
De determination for samples from the study area. 相似文献
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Testing the standardized growth curve (SGC) to OSL dating coastal sediments from the south Bohai Sea, China 总被引:2,自引:0,他引:2
Guang-Quan Chen Liang Yi Xing-Yong Xu Hong-Jun Yu Jian-Rong Cao Qiao Su Lin-Hai Yang Yong-Hang Xu Jun-Yi Ge Zhong-Ping Lai 《Geochronometria》2013,40(2):101-112
It has been suggested that the standardized growth curve (SGC) method can be used to accurately determinate equivalent dose (De) and reduce measurement time. However, different opinions regarding the applicability of the SGC method exist. In this paper, we evaluated quartz OSL SGCs of marine and coastal sediments of different grain sizes and different cores in the south Bohai Sea in China, and tested their applicability to the determination of De values. Our results suggested as follows: (1) The SGC method is applicable to both multiple- and single-aliquot regenerative-dose (MAR and SAR) protocols of OSL dating and efficiently provides reliable estimates of De. (2) Finesand quartz of different palaeodoses showed highly similar dose-response curves and an SGC was developed, but old samples using the SGC method have large uncertainties. (3) For coarse-silt quartz, two different types of dose-response curves were recorded: low-dose (≤60Gy) and high-dose (≥100Gy). The growth curves of low-dose quartz were similar to each other, facilitating the use of SGC in De estimations, but errors tended to be larger than those obtained in the SAR method. For high-dose (100–300Gy) quartz, the SGC was also found to be reliable, but there was large uncertainty in De (>300Gy) estimation. We suggest that SGC could be employed for the dating of marine and coastal sediments dating using either MAR or SAR OSL protocol and either fine-silt, coarse-silt or fine-sand quartz. 相似文献