元朝北疆范围研究

关于元朝的北疆范围，国内最盛行的说法是达到了北纬70多度的北冰洋海岸。此外，国内外还有到达了北纬60度一线、北纬56度一线等多种看法。本文通过历史文献考察，古代舆图与现代地图的勘合分辨，用现代科学解析计算历史上科学观测所得的数据和文献记载的疆域数据，并结合民族、历史、地理、考古、语言等情况及政治学原理，研究出元朝北疆大致到达了北纬60度一线，即今俄罗斯西伯利亚南部，个别地方达到了北纬63度，即今贝加尔湖以北。海南岛南端和贝加尔湖北端刚好在同一条经线上，这是元朝疆域南北跨度最大之处。     

The digital restoration of painted patterns on the No. 2 Qin bronze chariot based on hyperspectral imaging

The No. 2 Qin bronze chariot unearthed from Qinshihuang's Mausoleum is world famous for its huge size and colourful painted patterns. However, since it had been buried for a long time and was affected by its harsh environment, its painted patterns have been severely damaged. The traditional restoration methods, which mainly rely on expert experience, are manual, inefficient and lack scientific support. Moreover, to protect the important cultural relics, any invasive operations, such as sampling analysis, are strictly prohibited. This paper presents a method that combines hyperspectral imaging and computer technology for the digital virtual restoration of the bronze chariot's patterns. It is non-destructive, more efficient and more scientific. The method reproduces the damaged patterns with the following approaches: restoring the missing edges of the patterns; and distinguishing the different pigments. The obtained result implies that the method can digitally reproduce some of the damaged patterns, and that it can be used as a reference for recreating the patterns of the other painted bronze.     

明沈朝焕集的两种刻本

沈朝焕(1558-1616),字伯含,别号太玄,自称黄鹤山农,又称绿笠翁,钱塘(今杭州)人.生于嘉靖三十七年,卒于万历四十四年,万历二十年(1592)中进士,官至福建参政.     

大预应力锚索在将军崖岩画保护中的选择与应用

文章介绍了大预应力锚索在将军崖岩画保护中的选择与应用,强调了科学技术在文物保护中突出作用。     

长江流域史前古城的初步研究

一长江流域现已发现的史前城址（一）长江中游的史前城址长江中游现已发现的史前城址主要有湖南澧县城头山、湖北石首市走马岭、江陵阴湘城、荆门马家垸、天门石家河等。据报道湖南澧县鸡叫城,也是一座史前古城。据悉,长江中游地区现已发现的史前城址还有四、五座［１］...     

The two starting points of World War II: a reexamination from a global perspective

Although the factual chronology of World War II is not in dispute, how to best make sense of these facts and how to objectively evaluate that history have always been limited by political circumstances and personal biases. Viewing WWII seven decades later, we need to move away from Eurocentrism and to stop seeing the war from the prism of a European war or Pacific war. The entire history of WWII, from beginning to end, including its several phases characterized by fermentation, outbreak, climax, and conclusion, is extremely complex. This paper argues that the war has two origins or starting points because it resulted from disparate prewar conditions in Europe and Asia. Viewed from this perspective, the strategic importance of the China Theater in WWII and the enormous sacrifices and contributions the Chinese people made to the victory over Fascism and for world peace ought to be given due credit.     

论周恩来的非洲政策理念

周恩来总理为缔造中非友好关系做出了杰出的贡献,他的非洲理念奠定了中国对非洲外交政策的基础。周恩来作为马克思主义者,很早就树立了中国与非洲是命运共同体的基本认识,为了确定新中国对非洲政策,他又多次亲赴非洲进行实地调查研究。本文通过阐述周恩来非洲政策理念的形成、发展、要点及其典型实践,旨在为今天我们发展中非战略伙伴关系提供些许历史智慧。     

Exploring the potential linkages between oil‐field brine reinjection,crystalline basement permeability,and triggered seismicity for the Dagger Draw Oil field,southeastern New Mexico,USA, using hydrologic modeling

We used hydrologic models to explore the potential linkages between oil‐field brine reinjection and increases in earthquake frequency (up to M_d 3.26) in southeastern New Mexico and to assess different injection management scenarios aimed at reducing the risk of triggered seismicity. Our analysis focuses on saline water reinjection into the basal Ellenburger Group beneath the Dagger Draw Oil field, Permian Basin. Increased seismic frequency (>M_d 2) began in 2001, 5 years after peak injection, at an average depth of 11 km within the basement 15 km to the west of the reinjection wells. We considered several scenarios including assigning an effective or bulk permeability value to the crystalline basement, including a conductive fault zone surrounded by tighter crystalline basement rocks, and allowing permeability to decay with depth. We initially adopted a 7 m (0.07 MPa) head increase as the threshold for triggered seismicity. Only two scenarios produced excess heads of 7m five years after peak injection. In the first, a hydraulic diffusivity of 0.1 m² s^?1 was assigned to the crystalline basement. In the second, a hydraulic diffusivity of 0.3 m² s^?1 was assigned to a conductive fault zone. If we had considered a wider range of threshold excess heads to be between 1 and 60 m, then the range of acceptable hydraulic diffusivities would have increased (between 0.1–0.01 m² s^?1 and 1–0.1 m² s^?1 for the bulk and fault zone scenarios, respectively). A permeability–depth decay model would have also satisfied the 5‐year time lag criterion. We also tested several injection management scenarios including redistributing injection volumes between various wells and lowering the total volume of injected fluids. Scenarios that reduced computed excess heads by over 50% within the crystalline basement resulted from reducing the total volume of reinjected fluids by a factor of 2 or more.