对激光清除青铜器粉状锈技术的分析和探讨

用激光技术清除青铜器文物的粉状锈开辟了防治“青铜病”的一种新途径.本文阐述了粉状锈生成机理和激光清除粉状锈的基本理论,介绍用激光器处理粉状锈的一些实际情况.对把激光用于清除粉状锈,作者提出了从理论到实际应用中的一些看法,且认为该技术目前仍处于试验阶段。采用何种类型的激光器?如何控制激光参数?还需要做大量的试验和研究.进而指出,用非调 Q 脉冲式钕玻璃激光器进行清除工作,实际上对青铜器会带来严重损伤,对珍贵的青铜器文物不宜采用.     

New tools for rock art modelling: automated sensor integration in Pindal Cave

This paper presents the integration of automated sensors based on a terrestrial laser scanner and an amateur digital camera with the aim of generating a photorealistic three-dimensional (3D) model of the Principal Panel in Pindal Cave (Spain). The approach developed for 3D modelling overcomes many of the problems related to the independent implementation of photogrammetry and laser scanning. Particularly, a sequential and hierarchical approach was developed based on the processing and matching of images from the camera (camera image) and the laser scanner (range image). The results obtained demonstrate that the workflow for this model is automatic, effective, and accurate. The presented approach was found to create hyper-realistic models, even improving upon human visual capabilities.     

江西南昌雷鋽墓出土墨锭的分析研究

为了对江西南昌雷鋽墓出土墨锭的原料进行分析,加深对中国古代制墨工艺的了解,采用扫描电子显微镜,投射电子显微镜以及激光粒度仪对采自雷鋽墓的墨锭进行了研究,并与当代传统工艺生产的松烟、油烟以及工业生产的炭黑进行了比较分析。结果表明,雷鋽墓出土墨锭的烟炱颗粒形态及大小分布的均一性等与松烟非常相似,可以确定该墨锭应为松烟制作而成。     

Groundmass microsampling using laser ablation time-of-flight inductively coupled plasma mass spectrometry (LA–TOF–ICP–MS): potential for rhyolite provenance research

Provenance research using rhyolite formations that cooled too slowly to form obsidian has proven difficult for geochemical researchers to date. Uncertainties about the temperature regimes within the parent magma chamber and subsequently of the eruption process itself yield highly divergent phenocryst compositions and quantities. Variable and uncertain phenocryst composition and content make bulk and surface compositional analysis techniques (e.g., INAA, XRF) ineffectual without efforts to homogenise or render samples into solutions. This is frequently not a viable option for archaeological materials, thus rendering provenance research on rhyolite artifacts impractical using traditional techniques.     

Practical quantitative lithic use-wear analysis using multiple classifiers

Although use-wear analysis of prehistoric stone tools using conventional microscopy has proven useful to archaeologists interested in tool function, critics have questioned the reliability and repeatability of the method. The research presented here shows it is possible to quantitatively discriminate between various contact materials (e.g., wood, antler) using laser scanning confocal microscopy in conjunction with conventional edge damage data. Experiments with replica and prehistoric tools suggest the quantitative method presented here provides valid functional inferences and is flexible enough to accommodate other relevant sources of data on tool function.     

A proof of concept demonstration of the automated laser removal of rock from a fossil using 3D X-ray tomography data

Laser removal of rock from around a fossil using 3D data was demonstrated was the first time. This proof of concept combines the power of two technologies: X-ray micro-computed tomography scanning and programmable scanning laser ablation. This simple demonstration holds promise for the semi-automated and entirely safe laser removal of bulk material from around precious fossils.     

试论数据采集与虚拟修复在大足石刻修复中的应用

文物作为一种不可再生的宝贵资源,其本体上的保护修复工作均需慎之又慎,需遵循国际上规定的“最小干预”及“可逆性”基本原则.为此,虚拟修复成为对文物动手修复时的重要辅助手段.然而,多数文物具有复杂立体结构和色彩,传统的虚拟修复技术难以实现逼真效果.三维激光扫描是近年来飞跃发展的一项高新测绘与信息技术,具有无损、空间精度高、速度快等突出优势,在文物数字留存及相关保护应用中发挥了重要作用.三维激光扫描技术与高清摄影技术相结合,为文物的虚拟修复带来新的契机.本文结合文物虚拟修复基本需求分析,提出了基于三维激光扫描技术的文物虚拟修复关键技术与工作流程,并以国家一号石质文物保护工程——大足石刻宝顶山千手观音造像的保护修复为例,进行了应用实践,综合历史资料和现有数据的分析,实现了三维形态及色彩的虚拟修复.结果表明,基于三维扫描的虚拟修复能够提供更为逼真的三维虚拟修复模型,供修复专家研究参考.     

Mapping prehistoric social fields on the Sepik coast of Papua New Guinea: ceramic compositional analysis using laser ablation-inductively coupled plasma-mass spectrometry

The Sepik coast of northern Papua New Guinea is one of the most linguistically diverse places on earth despite communities there currently being connected into wide-reaching social and economic networks that cross language boundaries. One possible explanation for observed human diversity is that social connections were substantially less intensive prior to colonial pacification. As a proxy for human interaction, we compositionally analyzed 287 ceramic sherds from archaeological contexts using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to determine their place of production. Our results indicate that ceramics produced on Tumleo Island—currently the most important regional ceramic producer—were transported to other places on the Sepik coast after ∼1000 BP, suggesting that linguistic diversity on the coast has been maintained in an interactive environment for at least a millennium.     

Lost writing uncovered by laser two-photon fluorescence provides a terminus post quem for Roman colonization of Hispania Citerior

In this work, two-photon absorption fluorescence is used as a non-destructive method to detect the presence of paint upon an archaeological sample. The objective was to recover writing that, due to the discoloration caused by the passage of the time, was barely readable. The technique has been successfully applied to determine the consular date painted upon the neck of a Dressel 1A amphora found in the Roman village of Iesso (Guissona), in Catalonia. The identification of the consular date provides a terminus post quem for the foundation date for the city as well as a starting date for the Roman colonization of Hispania Citerior.