秦俑博物馆陶器库房空气污染的物理化特征及其对彩绘陶器的影响

2007年冬季在秦始皇兵马俑博物馆陶器库开展了室内大气污染系列采样工作,持续31天,使用Minivol便携式气溶胶采样仪采集了大气颗粒物样品（PM2．5）,利用AreaRAE—IAQ（PGM5220）测定了库内的微气候特征。结果表明,冬季兵马俑陶器库中的PM2．5的平均质量浓度为76．1μg／m3,明显低于室外,PM25中水溶性离子主要由SO4^3-、NO^3-和NH4^＋组成,与室外相同,表明库内污染物主要受室外控制,而且库内颗粒物偏酸性,库内温差较大,由于颗粒物偏酸性可能会对库内的陶器彩绘颜料中的碳酸钙、碳酸钡及硅酸铜钡等成分产生不利影响,颗粒物的悬浮与沉降也可能会对彩绘产生污损,此外库内剧烈的温度变化也可能会对彩绘陶器的保存带来不利影响。     

Development of Damage Patterns and Fragility Curves in Brick-nogging Buildings from the Thabeikkyin Earthquake,Myanmar, 2012

The Thabeikkyin earthquake (moment magnitude scale of 6.8) occurred on November 11, 2012; its epicenter was located 25 km from Thabeikkyin Township, Mandalay Region, Myanmar. Many buildings were damaged severely during the earthquake. In this study, damage patterns of brick-nogging buildings were firstly developed, and damage grades were characterized to allow for easy classification of the damaged buildings. The damaged data of all building types in the surveyed areas were collected by classifying the four damage levels as no damage, slight damage, moderate damage, and heavy damage. To develop the damage patterns of brick-nogging buildings, damage categories were arranged into three damage grades (slight, moderate, and heavy damage). Secondly, a questionnaire survey was conducted to calculate the seismic intensities of the affected areas. Medvedev–Sponheuer–Karnik (MSK) seismic intensities for the surveyed areas were estimated by analyzing the questionnaire survey responses. Finally, fragility curves for brick-nogging buildings were constructed using the estimated seismic intensities from the survey responses combined with the damage levels. These fragility curves may be useful to assess damage to brick-nogging buildings and to predict the number of damaged buildings in future earthquakes.     

Thermoluminescence age of quartz xenocrysts in basaltic lava from Oninomi monogenetic volcano, northern Kyushu, Japan

We determined the eruption age of basaltic rocks by application of thermoluminescence (TL) method, which is often used for TL dating, to quartz. Mafic magma only rarely includes quartz because of their mutual disequilibration. The basaltic lavas reported herein include quartz as xenocrysts, as corroborated by their rounded or anhedral shape. The basaltic lava used for this study is from the Oninomi monogenetic volcano in northern Kyushu, Japan. The volcano eruption was estimated as occurring 7.3–29 ka because the lava exists between two widespread tephras: Aira-Tanzawa ash (26–29 ka) and Kikai-Akahoya ash (7.3 ka). We succeed-ed in collecting ca. 200 mg of quartz by decomposition of 30 kg of the lava samples. TL measurements for the lava indicate the eruption age as 15.8 ± 2.5 ka, which is fairly consistent with the stratigraphical estimation. Although the TL method has played a considerable part in constraining the timescale of Quaternary events, its application has been limited to silicic samples. The present result demonstrates the availability of quartz for dating even of mafic rock.     

西汉张安世墓葬M1墓室内的大气环境调查

了解待发掘封闭墓葬内的大气环境,可为考古发掘和文物保存环境研究提供科学依据。西汉张安世墓园中的M1墓葬是一座未被盗扰的墓室,本研究在墓室开启前,有针对性地监测了墓室内的微气候参数和大气污染物。结果显示,相对于外界大气,密闭的墓室内低温、高湿、缺氧,且酸性气态污染物浓度较低。因此,在考古发掘及后续保存文物时,应针对不同文物材料采取密闭容器、保湿、避光等措施,避免由于环境骤变导致文物的风化损坏。本研究建立的待发掘墓葬大气环境测试体系及基础数据,可为相关考古和文保工作提供有益的借鉴。     

Wood identification of a wooden mask using synchrotron X-ray microtomography

Recently, an old wooden mask was discovered at Yatsushiro city, Kumamoto Prefecture, Japan. This mask has been handed down from the end of the 16th century; a Japanese man of arms brought it from the Korean Peninsula during the war between Japan and Korea. In the Korean Peninsula, Hahoe masks have been stored in the Hahoe village and were designated as national treasures in 1964 and are presently possessed by the National Central Museum. Some concerns existed that this wooden mask could be one of the Hahoe masks. Since the Hahoe masks in Korea have all been made of alders (Alnus spp.), wood identification became a key issue to answer the abovementioned concerns. In fact, a flaked sample fragment was available and it was small and brittle enough to be sectioned without embedding. Furthermore, the sample was compressed in the tangential direction so that the surface was not clear enough to be explored by a scanning electron microscope. In this study therefore, a synchrotron X-ray microtomography at SPring-8 was used for the first time for wood identification. The experimental setup of BL20XU at SPring-8 allowed us to image any wood sample at a special resolution of 0.5 μm, which is enough to explore most anatomical features for wood identification established using optical microscopy. The sample was clearly diffuse-porous hardwood characterized by uniseriate heterogeneous ray and simple perforation. As a result, the mask turned out to be made of Salix sp., and the possibility that it is one of the Hahoe masks was ruled out.