明代勋卫与散骑舍人的制度特性

明代的勋卫与散骑舍人是宫廷侍卫中的特殊成员。明初,勋卫、散骑舍人均从勋贵、都督、指挥等中高级将领的子弟中选任,并铨注于锦衣卫衙门,职在带刀随从帝王朝会。明中期之后,散骑舍人渐不授,而勋卫演变为勋爵应袭子孙例授之职,与勋爵承袭制度密切相关。至嘉靖、隆庆之际,朝廷尝试扩展部分勋卫的职权,但总体成效不显。勋卫、散骑舍人制度是明代多种国家制度的结合点,体现了明代军政体制中的贵族特征。     

《藏行纪程》所载滇藏交通研究

《藏行纪程》详细记载了康熙末年杜昌丁自云南昆明至西藏洛隆宗的往返行程,是《三省入藏程站记》、《西藏通览》、《西藏新志》、《西藏志》等书滇藏交通部分的直接或间接资料来源,是研究清代滇藏交通的珍贵史料。文章通过对道路沿线地名的考证和梳理后发现该书多处地名顺序有误;该道路只在康熙末年及雍正年间用兵西藏时设过台站,其间屡设屡撤,云南的驿道也未延伸至西藏,称其为滇藏驿道并不恰当;与之相比,《藏纪概》所载滇藏台站更加准确和权威。     

文物的赋存环境及其预防性保护问题

我国是世界上历史最悠久的古国之一,拥有为数众多的具有历史、科学、社会及经济价值的文物。本研究尝试综述了从文物与其赋存环境关系的角度,将文物赋存环境分为全曝露自然环境、半曝露自然环境及人工营造环境,通过分析赋存环境对文物的影响,探讨文物赋存环境的转化过程,提出不同环境条件下文物的预防性保护问题。     

百年来中国对韩国史学史研究的回顾与展望北大核心CSSCI

20世纪初,随着朝鲜汉籍陆续进入中国学术视野,中韩史学比较研究陆续展开,孟森、吴晗等史家作出了重要贡献。从1949年到1992年中韩建交前,中国大陆学界对韩国史学的关注较少,中国台湾出版了一批韩国史学史研究成果,延续和拓展了相关领域。1992年中韩建交对于中国韩国学的发展有至关重要的作用,在韩国史学史、中韩史学交流与比较等领域都有一批学术成果问世。回顾百余年来韩国史学史研究的历程,中国学术界的研究成果呈现如下特点:论文较多,专著较少;专题性、叙述性的评介较多,全面系统的论述较少;对韩国汉文史籍的关注较多,非汉文韩国史籍甚少;自说自话的论著较多,与韩国学术界的对话较少。针对这些问题,还需做更全面的努力,以推动韩国史学史研究。     

土质文物盐害中硫酸钠的研究——从微观到宏观

土遗址和壁画遗址可溶盐主要为NaCl和Na_2SO_4,其中Na_2SO_4是破坏程度最严重的盐。一般认为,硫酸钠只有在温度、湿度变化时才不稳定,才发生得失结晶水引起的晶型及体积变化。为研究土质文物盐害的形成机制及内在原因,调研了全国几处典型土遗址和壁画遗址的盐害状况并取样分析。分析发现:1)土遗址和壁画遗址中硫酸钠的形貌、结构是动态变化的(无论在任何极端干燥环境甚至真空条件下);2)环境因素如温度、相对湿度的变化只是加剧上述变化进程。硫酸钠结晶析出时,其体积膨胀约4倍。这一系列的过程,深刻影响着硫酸钠的相变复杂性和对依存土质文物本体的破坏性。本工作从微观和宏观两个层面探讨了这些发现,并通过不同盐分(不同浓度氯化钠、硫酸钠)侵蚀破坏模拟试验、不同温度条件下模拟试验、不同相对湿度下模拟试验,从宏观层面印证了上述微观机制在土遗址和壁画遗址本体的外在表现。本研究发现土遗址中硫酸钠的形貌、结构是动态变化的,该工作弥补了以往研究和认识上的局限。本研究将对阻止、延缓及预测土质文物盐害的发生、发展提供科学参考。     

A Discussion on the Emergence and Development of Ancient Chinese Artificial Barium Copper Silicate Pigments from Simulation Experiments

The ancient Chinese barium copper silicate minerals mainly comprise Chinese purple (BaCuSi₂O₆) and Chinese blue (BaCuSi₄O₁₀), which were widely used from the late Warring States Period to the late Eastern Han Dynasty. In order to clarify the raw material of the pigment, a series of simulation experiments was conducted to produce Chinese purple pigment under varying mineral conditions. The minerals that we applied in the experiment were quartz as the source of silicon, malachite and copper oxide as the sources of copper, barite and witherite as the sources of barium and lead oxide as the source of lead. Simulation experiments showed that the barium copper silicate minerals and the purple pigment can be produced easily when witherite is used as the barium‐containing raw material. From the perspective of mineral resources, the birth of the ancient Chinese pigment associated with a unique barium mineral resource. The Chinese copper‐based pigments are assumed to have been developed independently and are presumably an outcome of historical developments in glazing techniques.     

Spatial Distribution of City Tweets and Their Densities

Social media outlets such as Twitter constitute valuable data sources for understanding human activities in the virtual world from a geographic perspective. This article examines spatial distribution of tweets and densities within cities. The cities refer to natural cities that are automatically aggregated from a country's small street blocks, so called city blocks. We adopted street blocks (rather than census tracts) as the basic geographic units and topological center (rather than geometric center) to assess how tweets and densities vary from the center to the peripheral border. We found that, within a city from the center to the periphery, the tweets first increase and then decrease, while the densities decrease in general. These increases and decreases fluctuate dramatically, and differ significantly from those if census tracts are used as the basic geographic units. We also found that the decrease of densities from the center to the periphery is less significant, and even disappears, if an arbitrarily defined city border is adopted. These findings prove that natural cities and their topological centers are better than their counterparts (conventionally defined cities and city centers) for geographic research. Based on this study, we believe that tweet densities can be a good surrogate of population densities. If this belief is proved to be true, social media data could help solve the dispute surrounding exponential or power function of urban population density.     

“Our Girls Have Grown Up in the Family”: educating German and Chinese girls in the nineteenth century

In this article, we examine and compare historical changes in girls’ home-based education in nineteenth-century Germany and China. In many ways, girls’ home-based education in these two historical contexts exhibited differences, including the relationship between formal schooling and home education, and the role that new genres played in shifting tradition and structuring girlhood. However, we argue that more commonalities between the German and Chinese cases emerge. By analyzing the relation between talent and virtue, the writing of exemplary lives, and family dynamics, we see that in both cases the home was the critical site for valorizing and reproducing the class-bounded ideology of domesticity and identification for girls as home-based education constituted the means by which knowledge, morality, and practical skills were produced and transmitted from generation to generation.     

Direct inversion of Young's and Poisson impedances for fluid discrimination

Seismic inversion with prestack seismic data such as amplitude variation with offsets (AVO) inversion is an important tool in the estimation of elastic parameters for predicting lithology and discriminating fluid in conventional or unconventional hydrocarbon reservoirs. The product of Young's modulus and density (Young's impedance, YI) and the product of Poisson ratio and density (Poisson ratio impedance, PI) show great potential in lithology prediction and fluid discrimination of unconventional resources such as shale gas or oil. The high quality requirements for prestack data in density inversion render the estimation of YI and PI arduous and inaccurate with a conventional prestack inversion approach. In this study, a direct AVO inversion approach is proposed to estimate YI, PI, and density directly from P‐wave seismic data. The linearized P‐wave reflectivity approximate equation in terms of YI, PI, and density is initially derived. Five models, including four typical AVO classes, are utilized to verify the accuracy of the derived linearized P‐wave reflectivity equation in comparison with the exact P‐wave reflectivity equation and the frequently used linearized reflectivity approximate equation involving P‐ and S‐wave velocities and density. Parameter sensitivity analysis illustrates that YI and PI can reasonably be estimated from P‐wave reflectivity if a decorrelation scheme is utilized in the inversion algorithm. In addition, a pragmatic AVO inversion using a Bayesian scheme is suggested for the direct inversion of YI and PI from prestack seismic data. Synthetic and field data examples demonstrate the feasibility of the proposed inversion approach in the estimation of YI and PI and show the potential of this approach in fluid discrimination.     

定边郝滩东汉壁画墓绿色底层颜料分析研究

本研究以定边郝滩东汉壁画墓中绿色底层为研究对象,采用偏光显微镜(PLM)、带能谱的扫描电子显微镜(SEM/EDS)、X射线衍射仪(XRD)和拉曼光谱(RS)分析了绿色底层的成分与物相,同时和四种已知国外绿土相比较,得出绿色底色为绿土,对其进行深入分析研究以期为考古学和后期文物保护工作提供科学信息。