A new antiarch placoderm from the Emsian (Early Devonian) of Wuding,Yunnan, China

Pan, Z., Zhu, M., Zhu, Y. &; Jia, L., August 2017. A new antiarch placoderm from the Emsian (Early Devonian) of Wuding, Yunnan, China. Alcheringa 42, 10–21. ISSN 0311-5518.

Wufengshania magniforaminis, a new genus and species of the Euantiarcha (Placodermi: Antiarcha), is described from the late Emsian (Early Devonian) of Wuding, Yunnan, southwestern China. The referred specimens were three-dimensionally preserved in black shales, allowing a high-resolution computed tomography reconstruction of anatomical details. The new euantiarch is characterized by a large orbital fenestra, an arched exoskeletal band around the orbital fenestra and a developed obtected nuchal area of the skull roof. Maximum parsimony analysis, using a revised data-set of antiarchs with 44 taxa and 66 characters, resolves Wufengshania gen. nov. as a member of the Bothriolepididae, which is characterized by the presence of the infraorbital sensory canal diverging on the lateral plate, and the nuchal plate with orbital facets. New analysis supports a sister group relationship between Dianolepis and the Bothriolepididae. Luquanolepis, a coeval euantiarch from the neighboring site of the new form, is referred to the Asterolepidoidei and represents the basalmost and earliest member of the Asterolepidoidei.

Zhaohui Pan* [panzhaohui@ivpp.ac.cn], Min Zhu* [zhumin@ivpp.ac.cn], You’an Zhu^? [zhuyouan@ivpp.ac.cn] and Liantao Jia [jialiantao@ivpp.ac.cn] Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, PR China. *Also affiliated with University of Chinese Academy of Sciences, Beijing, 100049, PR China. ^?Also affiliated with Uppsala University, PO Box 256, 751 05 Uppsala, Sweden.     

Flexural Behavior of Typical Chinese Traditional Timber Stitching Beams

In Chinese traditional timber buildings, stitching is very common. When the bearing capacity or the rigidity is inadequate, a timber beam is often strengthened with another beam using the stitching method. The timber stitching beams are mainly of two types—the small-top/big-bottom type and the big-top/small-bottom type. To study the bending behavior of these two types of timber stitching beams, including the failure mode, the flexural capacity, the strain distribution at mid-span section, and the maximum deflection, bending tests are carried out on 14 timber stitching beams with Chinese traditional conformation for seven pine beams and seven fir beams. The results show that the failure modes of the small-top/big-bottom type of stitching beams all show brittle fractures at the bottoms of the bottom beams. The failure modes of the big-top/small-bottom type of stitching beams all show brittle fractures at the bottoms of the top beams. The distribution of section strain along the height of each part of the beam basically obeys plane hypothesis. Based on the theoretical and experimental analysis, the calculation formulas of flexural capacity and maximum deflection of these two types of timber stitching beams made of pine and fir are presented.     

Fluid mixing induced by hydrothermal activity in the ordovician carbonates in Tarim Basin,China

Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ¹³C, δ¹⁸O, δ³⁴S, and ⁸⁷Sr/⁸⁶Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), ⁸⁷Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also ⁸⁷Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ¹³C, δ¹⁸O, and ⁸⁷Sr/⁸⁶Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of ¹²C‐rich (δ¹³C as low as ?13.8‰) calcite and ³⁴S‐rich (δ³⁴S values from 21.4‰ to 29.7‰) H₂S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration.     

近代中国的领券制度

银行业的领券制度,是近代中国货币发行史上一项独特的制度。笔者由于工作的关系,曾对领券制度产生的源流做了初步的梳理。然而,现存关于领券制度的资料比较缺乏,在这方面的研究有待深入。本文仅是提供一些基本情况,并谈点自己肤浅的看法。     

论日欧首脑外交

首脑外交是第二次世界大战以来国家间交往的一种频繁使用的外交形式,随着国际格局多极化与世界经济全球化的发展,首脑外交也日益突显出其独特作用,并且为当今大多数国家的政治首脑所接受,冷战约束后,首脑外交更加趋向于公开化,制度化,全球化,在当今国际新秩序的构建过程中,资本主义世界的铁三角同盟（日美欧战略三角）也面临着战略性的结构调整,向着全球性战略伙伴关系发展,日本与欧盟及其成员国的关键日益密切,日欧间首脑的频繁互访无疑发挥了重大的作用。     

山地聚落历史人口的重建:以近三百年云南峨山沿河村为例

重建山地聚落人口变化的时空过程对认识历史时期人口发展有重要意义。本文以西南山地聚落沿河村为例,以田野调查资料为主,辅以历史文献和档案,利用估算户数和户均口数的方法重建了沿河村近三百年的人口变化过程。户数以某一时点占主导的世代可婚男子数作为代用指标进行折算;户均口数使用家庭结构模型,以流域内多个聚落人口的婚姻、生育和死亡数据推算出时段上的平均值,再通过1953年流域人口的年龄构成和多个聚落的户均子女和老人数得到平均值作为经验值,代入1920年之前户均口数的重建中,得到长时序的户均口数。重建结果通过对比检验,表明该方法能较好地重建历史时期山地聚落代际分辨率的人口序列。分析发现,该山地聚落人口变化具有大起大落和阶段性发展的特征,且大落的速度比大起的速度快。     

唐代墓志中新见唐人著述辑考

唐代墓志保存了大量唐人、唐代社会和唐代文化等方面的真实史料,具有极高的文献价值.近年来,随着唐代墓志的大量出土,学术界对唐代墓志的研究广泛展开,唐代墓志在文献辑佚、校勘、考定等方面正发挥着越来越重要的作用.许多学者利用唐代墓志,作了许多积极和卓有成效的研究,取得了许多令人可喜的研究成果,程章灿先生《唐代墓志中所见隋唐经籍辑考》(发表于《文献》1996年第1期)一文就是其中一项颇具价值的研究成果.     

史学研究中利用地方志的几种方法--兼谈方志的资料性与学术性

地方志在史学研究中的价值已为人熟知,本文重点探讨史学研究中利用方志资料的几种不同取向,即作为资料直接引用、作制度分析后引用、透过背后社会权力话语后引用和透过文化规范后引用等4种利用方志的不同方式,并试图发现它与近年来学术思潮和史学研究的转向可能存在的关系,以及我们究竟能在多大程度上利用地方志资料.在此基础上,作者认为方志是一种资料性著述,并且建议第二轮新修方志应加强对首轮修志情况的记述.     

论20世纪20年代苏联的外交政策

我国学界对20世纪20年代苏联对外政策存在不同的评价意见。本文从斯大林、契切林的外交政策理论以及他们对苏联外交政策影响的角度对20年代苏联对外政策进行了探讨。认为斯大林、契切林都继承了列宁晚年的外交思想,斯大林在20年代已经把世界革命的胜利寄希望于未来,提出了“一国社会主义”理论,契切林已把社会主义的未来和东方被压迫民族的解放运动联系在了一起。在对外政策方面,斯大林、契切林都把苏联国家利益放在外交政策考虑的优先地位。在实践上,虽然斯大林有时依然表现出了对世界革命的追求,但契切林以其长期担任苏俄外交人民委员的经历和丰富经验影响了斯大林以及苏联外交政策的制定和实施。从整体上看,苏联20世纪20年代的对外政策尽管存在一些失误,但基本把握住了列宁晚年思想的方向,为苏联国内建设创造了和平有利的外部环境。     

从砍斫器到石斧：再修锐技术的演进

狩猎采集群的重要压力在于石料的采办。当石制品系统中一个部分的变化抬高采办成本并超过可接受限制时,系统中就必然出现其它方面的补偿性变化。在本文中,系统的两个最易变的部分包括：（1）被处理原料的数量;（2）由再修锐技术决定的工具使用寿命。主要由于随时间增加的切割需求,也因为木器、狩猎和筑房技术的进步,再修锐方式从硬锤打击,转向软锤打击、石片再修锐、压制法再修锐,最终转向刃缘磨光。该模式指出,