大理岩石刻文物黑色结壳清洗研究

大理岩是古代石刻和建筑的主要石材之一。随着近现代工业发展,很多大理岩石刻文物表面出现了大量黑色结壳——不仅严重影响了文物外观审美,而且会不断吸附各种污染物,吸收更多的辐射热量,造成文物的进一步劣化,因此亟需清洗。在前期对北京地区石刻文物本体及黑色结壳科技分析的基础上,选用碳酸铵法、乙二胺四乙酸法、物理法进行清洗试验用于对比,并于北京不同区域的6处典型石刻上进行现场试验,根据实际情况做出优化改良。采用便携式X射线荧光光谱仪、分光测色仪、显微镜和离子色谱仪对清洗前后状态及可溶盐含量进行评估,结果表明碳酸铵法对大理岩石刻文物表面黑色结壳具有较好的清洗效果,清洗方案比较高效合理,有助于相关石质文物病害的清洗和保护。     

Determinants of Market Extension in Knowledge-Intensive Business Services: Evidence from a Regional Innovation System

Several studies have emphasized the role of knowledge-intensive business services (KIBS) in fostering innovation in metropolitan areas and regional innovation systems. Such areas are capable of expressing a strong demand for KIBS and consequently stimulate the rise and growth of KIBS. Despite an abundance of literature on KIBS emphasizing the relevance of spatial proximity to customers, many KIBS develop relationships on a broader national or even international scale. No studies have focused explicitly on this apparent discrepancy as yet. The aim of this paper is therefore to fill this theoretical and empirical gap by explaining the firm-level factors relating to the market extension of KIBS within the framework of regional innovation systems. Our analysis is based on a quantitative study on more than 150 KIBS supplying design or communication services located in the Veneto region (north-eastern Italy), an area that can be described as a regional innovation system. Five variables were considered, that is, size, experience, service standardization, investments in network technologies and relational intensity. Our results confirm that three of these variables, but not service standardization and relational intensity, correlate positively with the market extension of KIBS. Policy implications are also discussed.     

基于GIS的家谱资源整合集成研究

我国家谱源远流长、内容丰富、数量巨大,一直是众多领域学者关注的焦点。但是,家谱研究始终处于初级阶段,家谱的价值尚未得到充分利用。其根本原因在于家谱资源分布广泛、共享困难、研究方法和手段单一。各方通力合作,利用高新技术整合现有家谱资源,建立中华家谱总数据库和总平台已迫在眉睫。本文针对家谱典型的时空特性,提出采用GIS技术整合集成海量家谱资源,并进一步探讨了家谱资源整合集成的若干关键问题,设计了家谱资源整合集成的基本原则和平台框架,为家谱研究提供了新的思路、方法和技术。     

Jet-Pacs Project: Dynamic Experimental Tests and Numerical Results Obtained for a Steel Frame Equipped with Hysteretic Damped Chevron Braces

The experimental and numerical results obtained by Research Units of the University of Basilicata and University of Calabria for a steel frame, bare or equipped with metallic yielding hysteretic dampers (HYDs), are compared. The shaking table tests were performed at the Structural Laboratory of the University of Basilicata within a wide research program, named JETPACS (“Joint Experimental Testing on Passive and semiActive Control Systems”), which involved many Research Units working for the Research Line 7 of the ReLUIS (Italian Network of University Laboratories of Earthquake Engineering) 2005–2008 project. The project was entirely founded by the Italian Department of Civil Protection. The test structure is a 1/1.5 scaled two-story, single-bay, three-dimensional steel frame. Four HYDs, two for each story, are inserted at the top of chevron braces installed within the bays of two parallel plane frames along the test direction. The HYDs, constituted of a low-carbon U-shaped steel plate, were designed with the performance objective of limiting the inter-story drifts so that the frame yielding is prevented. Two design solutions are considered, assuming the same stiffness of the chevron braces with HYDs, but different values of both ductility demand and yield strength of the HYDs. Seven recorded accelerograms matching on average the response spectrum of Eurocode 8 for a high-risk seismic region and a medium subsoil class are considered as seismic input. The experimental results are compared with the numerical ones obtained considering an elastic-linear law for the chevron braces (in tension and compression), providing that the buckling be prevented, and the Bouc-Wen model to simulate the response of HYDs.     

Electron paramagnetic resonance of mosaic glasses from the Mediterranean area*

Ancient mosaic glass tesserae sampled from archaeological sites located in the Mediterranean area have been analysed by Inductively Coupled Plasma‐Optical Emission Spectroscopy (ICP‐OES). The aim of the research was to understand the role played by 3d transition metals in the optical properties of such samples. In order to better identify the specific effect of the main chromophorous element, modern samples have been prepared in the laboratory by adding to a colourless base frit controlled concentrations of colouring oxides. Samples with compositional and optical properties similar to the ancient ones have been obtained. For all these modern samples, as well as for all the ancient ones, electron paramagnetic resonance (EPR) measurements have been performed. The features of the EPR spectra could be successfully associated with the presence and abundance of the paramagnetic colouring ions (namely iron, manganese and copper) and to their oxidation states. This could be a basic step towards understanding the provenance and chronological attribution of mosaic glass tesserae.