多尺度下中国人口老龄化风险集群的时空格局——Flexible空间扫描计量方法的应用

运用Flexible空间扫描计量方法,对比分析了省、市和县域尺度上的老龄化风险集群的时空格局。发现：老龄化成为全国人口结构转型的主旋律,少子化成为新常态,老龄化区域非均衡加剧,并存多种区域模式;三种尺度识别出的风险集群都集中分布于东南半壁;集群的风险程度与地域范围随时间不断扩大,但集群间的风险差异趋于缩小。总体而言,尺度越小,识别出的集群分布越分散,定位越精确,风险越高,差异越大。针对不同地区的人口-经济发展情况,提出保障生育,发展养老产业,基本公共服务均等化,就地、近城镇化等的老龄化风险应对策略。     

The Accumulation of Silica in Lakes

On the basis of available data on recent and fossil lake sediments with a high content of authigenic silica—diatomite—an attempt is made to identify those factors in the surrounding landscape and in the lake environment that account for the formation of these siliceous sediments. The presence of cause-and-effect relationships and the wide distribution of siliceous lake sediments, both at present and in the geological past, suggest that diatomite lakes can be treated as a distinctive lake type in a lake typology and limnological regionalization previously proposed by the author.     

中国居民消费增长波动多尺度变化及趋势研究

采用经验模态分解(EMD)方法对1953-2009年中国居民消费增长率波动进行分解,得到其IMF分量及趋势分量RES,运用方差贡献率及相关性检验其周期变化,并利用Mann-Kendall非参数统计检验方法对增长趋势进行研究。结果表明:中国居民消费增长波动存在3年、8年和12.4年的准周期,以准8年周期为主,准3年周期次之;56年来居民消费呈波动增长趋势,1978年是其突变点,当年对外开放政策的提出极大促进了居民消费增长,1983年居民消费增长率超过临界直线,此后呈显著上升趋势。经济因素、居民收入水平和消费结构是影响中国居民消费增长波动的主要因素。     

Microstructures of Building Materials from Huaca De La Luna,Peru

ABSTRACT

The microstructures of building materials from the archaeological complex of Huaca de la Luna on the northern coast of Peru is assessed for the first time by a multiscale approach. The multiscale microstructural characterization used laboratory techniques including optical microscopy, scanning electron microscopy, X-ray microtomography, and both gas and powder pycnometry. Optical microscopy revealed the presence of organic matter and shell fragments and X-ray microtomography showed differences in the sizes and connectivity of pores. The BET (N₂ gas adsorption) specific surface areas showed greater presence of clayey matrix in the mortars. No significant differences among mortars and brick fragments mineralogy were detected by X-ray diffraction, so the larger amount of fine binding matrix in the mortars suggests that they were produced blending raw material with different grain sizes. The aim of this study is to provide data that can be used for a better understanding of the Moche culture, its construction techniques, and to support conservation strategies of the archaeological heritage.