Eoshumardia (Trilobita,Cambrian), a junior synonym of Koldinioidia

Well-preserved internal and external moulds of a shumardiid species are described from the late Furongian (Late Cambrian) “Fengshan Formation” at Poben, Napo, southwestern Guangxi, which is close to the type locality of Shumardia orientalis, the type species of Eoshumardia. All features observed on the internal moulds indicate that the new material is definitely S. orientalis, whereas the morphology of the external moulds indicates that S. orientalis should be referred to Koldinioidia. The change of generic assignment of the type species means that Eoshumardia is a junior synonym of Koldinioidia.     

Bleached mudstone,iron concretions,and calcite veins: a natural analogue for the effects of reducing CO2‐bearing fluids on migration and mineralization of iron,sealing properties,and composition of mudstone cap rocks

This study investigates the Wangfu Depression of the Songliao Basin, China, as a natural analogue site for Fe migration (bleaching) and mineralization (formation of iron concretions) caused by reducing CO₂‐bearing fluids that leak along fractures after carbon capture, utilization, and storage. We also examined the origin of fracture‐filling calcite veins, the properties of self‐sealing fluids, the influence of fluids on the compositions of mudstone and established a bleaching model for the study area. Our results show that iron concretions are the oxidative products of precursor minerals (pyrite and siderite) during uplift and are linked to H₂S and CO₂ present in early stage fluids. The precipitation of calcite veins is the result of CO₂ degassing and is related to CO₂, CH₄, and minor heavy hydrocarbons in the main bleaching fluids. In our model, fluids preferentially enter high‐permeability fracture systems and result in the bleaching of surrounding rocks and precipitation of calcite veins. The infilling of calcite veins significantly decreases the permeability of fractures and forces the fluids to slowly enter and bleach the mudstone rocks. The Fe²⁺ released during bleaching migrates to elsewhere with the solutions or is reprecipitated in the calcite veins and iron concretions. The formation of calcite veins reduces the fracture space and effectively prevents fluid flow. The fluids have an insignificant effect on minerals within the mudstone. In terms of the chemistry of the mudstone, only the contents of Fe₂O₃, U, and Mo change significantly, with the content of U increasing in the mudstone and the contents of Fe₂O₃ and Mo decreasing during bleaching.     

基于环境犯罪学理论的入室盗窃时空分布研究——以北京市主城区案件的分析为例

以往关于犯罪时空特征的研究较多的侧重于对犯罪时空分布现象的描述分析以及从人文地理视角下的环境影响性分析,但缺少从环境要素与犯罪主体行为之间的相互作用机制下的犯罪时空特征研究。本文通过开展北京市入室盗窃案件的时空热点实证分析,总结和归纳了案件热点环境的时空要素类型,并基于环境犯罪学的基本原理,构建了基于犯罪主体与环境影响要素相互作用的犯罪时空分布机制,其中,环境对犯罪主体的影响主要表现为四类要素,即目标、交通、防范和作案时机。这些研究可以为下一步开展犯罪模拟以及犯罪预防提供借鉴。     

故宫藻井轩辕镜及配件的材料与工艺分析研究

紫禁城多个建筑的盘龙藻井中均悬有轩辕镜,但对轩辕镜的分析研究却很少。本研究采用多种仪器方法,对故宫万春亭藻井轩辕镜和画珐琅葫芦等配件进行了分析。万春亭轩辕镜的分析结果表明,轩辕镜玻璃基体为钾-铅玻璃,镀层采用了锡汞齐技术,生产时间晚于17世纪末;画珐琅葫芦配件的分析结果表明,画珐琅白色底釉组成与"玻璃白"原料相近,不同颜色珐琅釉基体均为钾-铅玻璃,黄色釉中铅锡黄同时发挥着色与乳浊的作用,蓝色釉为砷酸铅乳浊,胭脂红色为金红发色,棕色勾线呈色物质为赤铁矿。画珐琅釉料大部分经过预熔处理,绘制时按照白色底釉、棕色线条、其他色釉的顺序施加,最后烧制而成。     

Child loss and maternal wages in China

Using data from a random sample of the 2005 National Population Survey of China, we investigate the association between child death and maternal hourly wages. Approximately 1.6 per cent of the population has experienced at least one child death. Such bereaved mothers’ hourly wages are 53 per cent lower than those of non-bereaved mothers. We find that child death carries a significant wage penalty. Son death has a larger impact than daughter death and its effect decreases as the number of children in the household increases. Our decomposition results show that number of children, maternal education and regional characteristics are the three most important contributors to the wage gap, yet unexplained differences remain large, especially at the lower end of the wage distribution.     

滇黔桂省际边界区域城镇经济联系的网络结构特征与演化分析

以滇黔桂省际边界区域28个城镇为例,构建城镇中心性评价指标体系,利用改进的熵值法测度各城镇的中心性得分,评价滇黔桂省际边界区域经济空间结构演变,利用修正的引力模型测度了1995年、2004年、2014年3个年份各城镇之间经济联系强度;借助GIS技术手段分析了城镇经济联系强度的空间格局,评价城镇等级体系演化特征;最后利用社会网络分析方法考察了城镇经济空间联系和网络关系的演化规律,得出如下结论：滇黔桂省际边界区域中心城市逐渐形成,经济重心由南向北转移,由右江区单中心逐步发展到兴义市、右江区、文山市三中心,再到兴义市发展成为强中心,平果县与靖西市具备发展为滇黔桂次中心城镇的潜力;城镇间的经济联系总体较弱,区域整体网络密度低,但呈现出不断增强的趋势,低等级城镇对高等级城镇的引力与高等级城镇对低等级城市的引力不同,形成两种不同的城镇网络体系,经济联系紧密地区主要集中在中心城市之间及中心城市与经济强县之间;三角结构的外围经济联系密度明显较低,对于大多数城镇来说,尚不具备经济辐射能力,辐射效应极弱。     

Asynchronous,Iterative, and Parallel Procedures for Solving the Weighted-Region Least Cost Path Problem

A family of local, asynchronous, iterative, and parallel procedures (LAIPPs) are described. These procedures are designed to find least cost paths (LCPs) in bounded regions of the plane that have been partitioned into triangular subregions. The unit cost of traversing a given subregion is uniform within the subregion, but varies between subregions. In the case of one-dimensional chains of triangles, the procedures are guaranteed to converge to a global LCP. Although the procedures are guaranteed to terminate, we have so far been unable to prove, in the general case of a two-dimensional triangulation, that the procedures always terminate in admissible paths. Extensive experimental investigations, however, have revealed convergence to admissible paths in all cases examined. While counterexamples are constructed to prove that the procedures may converge to the local rather than global LCPs, convergence to the global LCP was found to occur in nearly all of our experimental investigations. The computational complexity of the procedures, as measured by the number of iterations required for convergence, was found experimentally to be independent of the size of the domain in which the paths lay, and to be slightly greater than linear in the Euclidian length of the paths. The complexity was also found to depend on the cost structure of the domain. Such LAIPPs appear to be promising procedures for both application and further investigation. In particular, the question of convergence is an interesting problem.     

矿区工业旅游开发研究——以江西德兴铜矿为例

矿区工业旅游在我国还没有得到很好的开发。本文以江西省德兴铜矿为例,探讨了矿区工业旅游开发的条件与旅游产品的特点,并对矿区工业旅游的景观形象设计与空间格局规划进行了讨论。     

The sources and formation processes of brines from the Lunnan Ordovician paleokarst reservoir,Tarim Basin,northwest China

The most important petroleum exploration target in the Tarim Basin, northwest China, is the paleokarst reservoir. To understand the source and evolution of brine in this type of reservoir, a total of 37 formation‐water samples were collected from the Middle‐Lower Ordovician paleokarst reservoir in the Lunnan oilfield. The δD‐δ¹⁸O correlation and Cl/Br ratios reflect the mixture of two fluids: meteoric water and evaporated seawater. The different degree of mixture divided samples into two groups. Group 1 samples, from deep strata (5150–6667 m.b.s.l.) in the east of the field, with elevated δD (?53.5 to ?38.0‰), δ¹⁸O values (0.66–5.99‰), and lower Cl/Br ratios (336–478 for Cl/Br, except LN634‐1 and LN631‐1) were formed by evaporation of seawater plus a small contribution from meteoric water. Group 2 samples, from shallow strata (5038–6067 m.b.s.l.), in the west of the field, have contrasting features (?59.6 to ?48.5‰ for δD, ?0.47 to 2.17‰ for δ¹⁸O, and 501 to 871 for Cl/Br), which reflect a mixture of evaporated seawater with a high proportion of meteoric water. Both of the fluid types exchanged oxygen isotope with minerals. The investigation into cation composition reveals that, before entering into the current reservoir, waters suffered albitization of plagioclase; moreover, meteoric water dissolved evaporites and seawater experienced dolomitization. A mixing trend showed by strontium isotopes (0.709801–0.711628) gave further evidence for the mixture of two fluid types. Based on the correlation of geological history with our data, two infiltration models of meteoric waters can be constructed. According to the chemical and isotopic compositions of the waters, an east fluid regime (Group 1) and a west fluid regime (Group 2) have thus been defined. Better understanding of the subsurface fluid movement patterns may be helpful for the local exploration.     

试述东北地区出土的金代瓷器

东北地区金代墓葬、城址、窖藏出土瓷器的类型主要包括定窑及本地窑场生产的白瓷(土产白瓷)、磁州窑风格的白地黑花瓷器、耀州窑青瓷、景德镇青白瓷器、黑(酱)釉瓷器、钧釉瓷器、翠蓝釉瓷器等。土产白瓷及白地黑花瓷的大量发现表明缸瓦窑、冮官屯窑等东北窑址在金代有新的发展,外来瓷器的大量输入则体现了金代东北与内地间的经济文化交流。