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1.
青海大通县出土汉代玻璃的研究   总被引:1,自引:0,他引:1  
本文共对12件玻璃样品进行化学组成分析.其中,部分样品还进行了密度测定,X 射线衍射分析和显微镜观察.此外,还对一颗黄色玻璃珠的表面层进行 SEM-EDX 分析.结果表明,该玻璃珠表面有金箔涂层.根据分析结果,青海大通县出土玻璃的基础成分可归为三类,即铅钡玻璃(Na_2O-PbO-BaO-SiO_2系统玻璃),钠钙玻璃和钾硅玻璃(K_2O-SiO_2系统)。此外,还对玻璃的来源进行了探讨.  相似文献   
2.
迄今已有2 700多年历史的铜鼓,是南方少数民族地区节日、喜庆、兵事、婚丧、祭祀、礼乐等场合使用的一种重器。为了对锈蚀状况做出科学的现状评估,为器物保护修复技术路线的制定和修复工作的开展提供科学指导,对玉林市博物馆馆藏7件铜鼓综合运用了体视显微镜、金相显微镜、激光显微拉曼光谱仪(RS)和环境扫描电镜及能谱仪(ESEM-EDAX)等仪器进行了金相组织和合金成分分析以及锈蚀产物的分析。分析结果显示:7件器物皆为泥范铸造成型,未见热、冷加工处理现象。7件铜鼓皆为铅锡青铜合金,总体呈低锡高铅的特点。组织形态呈典型α固溶体树枝晶偏析,锡含量处于6.0%~12.2%,分布较为集中,处于中等含量水平(5%≤Sn15%);铅含量处于14.4%~28.2%,铅含量普遍较高且分布较为集中,处于中高铅(10%≤Pb15%)和高铅含量(Pb≥15%)水平,合金中高铅含量配比应为工匠有意合金配比选择;铜鼓的腐蚀类型为α固溶体富铜相优先腐蚀,保存环境主要是富氧、少氯,铜鼓表面锈蚀产物主要为绿色孔雀石和蓝色蓝铜矿以及氧化物,有少量白色白铅矿。在保护修复工作中对于这些无害锈可保留,不予处理,并注重防氧。对于铜鼓表面夹杂泥土,需进行清洗去除。研究结果可为器物保护修复技术路线的制定和修复工作的开展提供科学指导。  相似文献   
3.
The bodies and glazes of 27 early Western Zhou proto‐porcelain samples from Yejiashan cemetery, Hubei Province, were analysed using LA‐ICP–AES, SEM, XRD, a thermal expansion instrument and other analytical methods. The results indicated that the bodies of all samples were characterized by high silicon and low aluminium, and were made with porcelain stone raw materials found in the south of China. The glazes are typical of high‐temperature calcium glazes of the CaO (MgO) – K2O (Na2O) – Al2O3 – SiO2 series, with relatively high Mn and P content, which was probably caused by the addition of plant ashes. The physical properties and phase compositions of Yejiashan proto‐porcelain show that firing processes were still in the early stages of development in ancient China. Multivariate statistical analyses indicated that Yejiashan proto‐porcelain might have come from the Deqing area, in Zhejiang Province. These results provide new archaeological evidence for research on issues related to material flow in the Western Zhou dynasty.  相似文献   
4.
许多出土饱水木质文物因其降解严重、含水率较高,容易在脱水过程中出现不可逆的收缩变形以及开裂现象,从而遭到严重破坏。因此,饱水木质文物脱水方法的研究是文物保护工作中的重要课题。为探究风冷冷冻法对饱水木质文物脱水的效果,以一批无法复原的出土饱水木质文物为研究对象,在对其材种、含水率、基本密度及化学成分进行了测定和分析后,使用一台风冷电冰箱在-18℃条件下对样品进行了风冷干燥脱水处理,记录脱水时间和脱水效果,并分析了该方法的传质传热特点,证明了风冷干燥法用于饱水木质文物的脱水干燥能够取得良好效果,并且具有对文物干预小、适用性广、操作简便、成本低廉等优点,为饱水木质文物的脱水处理提供了一种新的思路。  相似文献   
5.
Since the devolution of welfare policymaking to the states after the passage of the 1996 Personal Responsibility and Work Opportunity Reconciliation Act, there has been contentious debate about drug testing welfare applicants. Beyond elite rhetoric and debate points about the implications of welfare drug testing, extant research remains limited insofar as providing theoretical understanding about what factors influence state proposal of legislation requiring welfare applicants to submit to drug tests. I develop and test expectations that derive from research on welfare attitudes, social construction theory, and policy design—specifically, hypotheses that the proportion of blacks on state temporary assistance for needy families caseloads, as well as state‐aggregate levels of symbolic racism, significantly influence state proposal of drug testing legislation. My multilevel analysis of every state proposal of welfare drug testing legislation from 2008 to 2014 yields strong evidence in support of these hypotheses and paints a more complete picture of the influence of racial attitudes on state welfare policymaking. Specifically, while much research finds evidence of institutional racial biases in the implementation of welfare policy, the evidence presented herein shows that these biases, as well as public biases, influence policymaking at the proposal stage. Implications of these findings are discussed in light of recent significant electoral gains made by Republicans in state legislatures.  相似文献   
6.
The revelatory traditions found in chs. 2,7-12 of the book of Daniel are exceptional in connecting the historical circumstances pertaining to the persecution under Antiochus IV Epiphanes with the eschatological hopes of the Hebrew Bible. We will argue that the nature of this connection is twofold. On the one hand, for the redactor who gave the book of Daniel its canonical form, the distress associated with Antiochus was the distress associated with the last days. On the other hand, for the original composers of the book of Daniel, the distress associated with Antiochus was only a precursor to the distress associated with the last days. Finally, we will apply the insights gained from making this argument to the question of the book of Daniel’s composition.  相似文献   
7.
Traditions and transitions in Korean bronze technology   总被引:1,自引:0,他引:1  
Metallurgical examination of Korean bronze artifacts shows that a technical tradition based on casting and use of leaded high-tin alloys was established in Korea at the early stages of bronze use. After the subsequent discovery of quenching methods that suppress formation of the brittle δ phase, new thermo-mechanical techniques were introduced between the 7th and 10th centuries AD. Lead-free alloys were used, and tin contents near that of the peritectic point in the Cu–Sn phase diagram were chosen. Leaded high tin alloys continued in use, but only in cast objects, and with significant composition variation. The unique conditions during the time of innovation suggest that the transition to new metallurgical techniques was gradually achieved through domestic technical innovation inspired by external influences.  相似文献   
8.
姜萌 《史学月刊》2007,(3):79-85
《陈寅恪的最后二十年》、《顾颉刚和他的弟子们》、《束星北档案》等著作,代表了当前历史传记写作的一种趋势。《陈寅恪的最后二十年》的文本近似历史叙事散文;《顾颉刚和他的弟子们》的文本更接近史学论文;而《束星北档案》则类同电视记录片的文稿。这些著作共有的特点是:在修撰方式上,大量运用了第一手材料;在文本风格上,力求作品深入浅出、雅俗共赏;在写作理念上,坚持真实第一,尊重历史。这一趋势非常值得重视。  相似文献   
9.
采用显微观察、X射线衍射物相分析和X射线荧光光谱成分测试等手段,对湖北省巴东县雷家坪遗址六朝时期墓葬出土的若干精美“珠饰”进行了观察和分析,阐述了它们的特征,确定其材质;并与其他遗址出土不同时期的玻璃制品进行比较,发现其配方和我国西周至汉代玻璃,以及西方传统玻璃差别甚大。结合考古背景资料分析,这批珠饰很有可能是我国古代工匠在原有玻璃技术基础上,借鉴和吸收了外来玻璃的制造技术,在中国境内自行烧制的。  相似文献   
10.
为了研究刚出土的青铜器在新的环境中的发展变化情况,在宝鸡眉县27件国宝级西周窖藏青铜器出土一年半后,对这批器物出土前后的锈蚀类型及特征进行了分析和描述,并对每一器物的锈蚀产物进行了系统检测分析。结果显示,这批青铜器腐蚀类型主要为封闭环境中的大气腐蚀,主要产物为碳酸盐和氧化物。但同时在其中一个器物上发现了氯化物类有害锈成分,分析认为,出土前后环境的变化是有害锈得以产生和发展的根本原因。  相似文献   
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