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951.
为研究判定ATP(adenosine triphosphate,三磷酸腺苷)生物发光法在文物表面霉菌污染检测中应用可行性、科学性及适用性,利用ATP生物发光法对文物表面50种霉菌的生物发光值进行检测;构建了7种常见霉菌及其混合菌的菌落总数值与ATP生物发光值的线性关系函数,并在对应线性关系下分析了预测菌落总数值与实际值的差异;进一步利用ATP生物发光法评价模拟染霉试样在香茅醛熏蒸处理前后的霉菌数量变化。结果显示:50株待测霉菌中90%霉菌均检出了生物发光值(RLU)。在不同培养条件下,青霉、曲霉、木霉、毛壳菌、枝孢菌以及其混合菌的菌落总数对数值(lg^(CFU/mL))与生物发光对数值(lg^(RLU))之间均呈现了良好的线性关系,相关系数R^(2)>0.9817;在相应的线性关系下,预测的菌落总数值与实际平板计数的菌落总数值具有一致性(P<0.05),说明ATP生物发光法可以对文物表面霉菌进行准确相对定量。此外,香茅醛熏蒸处理组和对照组文物表面霉菌的生物发光值和菌落总数呈现了相同的差异变化趋势,说明ATP生物发光法可以直接用于熏蒸剂抑菌效力的评价。因此,ATP生物发光法在文物霉变检测中具有很高的适用性,同时在文物霉变程度分析及霉变文物消杀处理的效果评价等方面具有良好的应用价值,可为文物微生物病害的防控提供有效的技术支持。  相似文献   
952.
世界华商大会自1991年举办至今,已发展成为当今世界的一项知名盛会。本文分析了大会产生的背景,概述了第一届到第八届大会的基本情况,并指出其发展具有四个特点:一是大会经济、政治、文化等方面的综合性;二是大会组织逐渐成熟、举办经验更加丰富;三是大会与中国经济发展壮大具有某种同步性;四是历次大会的主题体现了与时俱进的特点。作者最后认为,应实事求是地评估大会的作用。  相似文献   
953.
Guanzhuang site is located in the west of Guanzhuang Village, Gaocun Township, Xingyang City, Henan Province. From the site, more than 3 000 pottery moulds have been unearthed, with various types, including the moulds for containers, tools, chariots, weapons, money and core, etc. According to the types and decorations of pottery moulds and the characteristics of co - existing pottery, the pottery moulds of Guanzhuang site can be divided into two periods—Phase I dating from the late Western Zhou Dynasty to the early Spring and Autumn Period, and phase TJ considered between the early and middle Spring and Autumn Period. The change of bronze ware styles from the Western Zhou Dynasty to the Spring and Autumn Period was important in the development of ancient Chinese bronze wares. Due to the lack of archaeological data, research on pottery moulds during the two - week period was still insufficient; discussion of the important issue of standardizing the sources of raw materials was also relatively weak. Environmental archaeology has relatively mature methods and practices in depositional dynamics, depositional processes and provenance tracing, which could provide new ideas for further in - depth discussions on this issue. In order to understand the material sources and craftsmanship of pottery moulds unearthed from Guanzhuang site in Xingyang, Henan Province, samples of Guanzhuang pottery moulds and natural sedimentary strata were studied using particle size analysis, XRF and petrographic analysis to give the following results. 1) The raw materials for mould - making were taken from the late Pleistocene Malan loess layer under the cultural layer of the site. The Malan loess underwent simple manual elutriation before being used to make pottery moulds. 2) A small amount of plant ash and calcium nodule powder was added during the production process of pottery moulds as an admixture to increase the high - temperature resistance. 3) The inner side of pottery mould for container was mainly made of Malan loess, while the outer one was made of a mixture of Malan loess and river sand with a blending ratio of about 7:5. Pottery moulds for various ware types had different processing techniques (e.g., moulds for containers were more refined). Besides, compared with early pottery moulds, later ones are relatively rougher, but the difference is not obvious. 4) The petrographic characteristics of double - layer container moulds indicate that there are different production processes for the inner and outer sides of mould. The inner side was made of Malan loess with finer particles—below 100 μm—as the raw material after elutriation, and there were traces of directional trimming. The outer one was made of a mixture of two parts of minerals (coarse and fine), and there was no obvious processing trace. Analysis of sample particle size is a new attempt to discuss the material sources of pottery moulds. The related discussion of mud - clarifying ponds is also helpful to understand the function of such relics and the formation process of accumulation in them. This study has important reference significance for exploring the material and craft characteristics of pottery moulds before and after the early Spring and Autumn Period in the Central Plains. © 2023, Sciences of Conservation and Archaeology. All Rights Reserved.  相似文献   
954.
金沙土遗址表面存在泛盐、粉化、空鼓等盐害。对这些盐害的分布特征与演化过程的研究是科学保护金沙土遗址的第一步,也是进一步探讨盐害致病机理的前提条件。本工作收集整理了2010~2020年金沙土遗址病害调查资料,通过现场调查和图像处理技术对盐害的类型、分布特征与演化过程进行定性和定量分析;采用X射线衍射、离子色谱和扫描电镜等测定了不同高度土样的成分、盐分含量以及微观结构。结果显示金沙土遗址主要的盐害类型为表面泛盐、粉化、空鼓、片状剥蚀和掏蚀;主要分布区域是西北向走廊和古河道附近,机挖坑侧壁最为严重;在探方侧壁上盐害由上到下依次由表面泛盐过渡到单独粉化,再到空鼓和片状剥蚀,最底层为掏蚀。金沙土遗址盐害的发育过程可以概括为四个阶段,每个阶段主要发育的盐害类型不同,依次为表面泛盐、粉化、片状剥蚀和掏蚀。越到后期,各类盐害分布范围越大,发展速度越快,对土遗址破坏性越大。离子浓度沿高度的分布与毛细上升作用有关,也与病害的劣化程度和发育进程有关。硫酸钙类是导致土遗址泛盐、粉化和脱落的主要盐分之一。  相似文献   
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