含芘氨基酸衍生物对水中Cd2+、Pb2+的高选择性识别研究

本文报道了一种新型含芘氨基酸衍生物-L-[4-（1-芘基）]丁酰基苯丙氨酸（缩写为PLT）,通过对PLT与离子结合前后其二聚体/单体荧光发射峰强度比的检测表明该衍生物对水中的重金属离子Cd^2＋和Pb^2＋表现出了极强的识别性能,而对水中所存在的其它离子则具有完全不同的响应特性.     

Paleo‐fires and Atmospheric Oxygen Levels in the Latest Permian: Evidence from Maceral Compositions of Coals in Eastern Yunnan,Southern China

Inertinite maceral compositions of the Late Permian coals from three sections in the terrestrial and paralic settings of eastern Yunnan are analyzed in order to reveal the paleo-fire events and the atmospheric oxygen levels in the latest Permian. Although the macerals in the studied sections are generally dominated by vitrinite, the inertinite group makes up a considerable proportion. Its content increases upward from the beginning of the Late Permian to the coal seam near the Permian-Triassic boundary. Based on the microscopic features and the prevailing theory that inertinite is largely a by-product of paleo-fires, we suggest that the increasing upward trend of the inertinite abundance in the latest Permian could imply that the Late Permian peatland had suffered from frequent wildfires. Since ignition and burning depend on sufficient oxygen, a model-based calculation suggests that the O2 levels near the Wuchiapingian/Changhsingian boundary and the Permian-Triassic boundary are 27% and 28% respectively. This output adds supports to other discoveries made in the temporal marine and terrestrial sediments, and challenges the theories advocating hypoxia as a mechanism for the Permian-Triassic boundary crisis.     

云南罗平中三叠统关岭组二段碳酸盐岩微相分析

通过详细的野外观察和室内镜下薄片分析,于中三叠统关岭组二段中初步识别出8种微相类型。结合宏观沉积构造及罗平生物群保存特征,认为云南罗平关岭组二段为碳酸盐岩缓坡沉积,可划分出深水盆地、深缓坡、深缓坡远端变陡、浅缓坡和后缓坡5个沉积相。沉积相在垂向上是向上变浅(海退)的沉积序列。罗平生物群的沉积环境为深水、低能、安静的海洋环境,突发的风暴事件导致了生物群大量死亡,并被迅速埋藏。     

Variability of Raindrop Size Distribution during a Regional Freezing Rain Event in the Jianghan Plain of Central China

The characteristics of the raindrop size distribution(DSD) during regional freezing rain(FR) events that occur throughout the phase change(from liquid to solid) are poorly understood due to limited observations. We investigate the evolution of microphysical parameters and the key formation mechanisms of regional FR using the DSDs from five disdrometer sites in January 2018 in the Jianghan Plain(JHP) of Central China. FR is identified via the size and velocity distribution measured from a disdrom...     

裂纹间动态相互作用的实验观测与理论分析──以共线剪切裂纹归并为例

本文以共线剪切裂纹的归并为例,研究裂纹系的动态相互作用．实验结果表明：在张破裂的意义上,小间距共线剪切裂纹的内端部实际上是阻碍结构,通过迂回弯曲的张破裂归并．本文提出一种估计张破裂扩展途径的近似方法,利用张应力破裂判据找出了潜在的破裂扩展途径的第一近似,较好地模拟了共线裂纹的破裂途径,和现有的数值模拟方法比较,可以大大缩短机时,简化计算程序,保证精确度．本研究结出了岩石剪切破裂“隧道效应”（即破裂跳过障碍体,而障碍体本身不破坏）的机理,还给出了脆性介质在摩擦、磨损过程中碎屑产生的机理．     

用天然地震探测青藏高原中部地壳、上地幔结构

从西藏南部的定日、嘎拉至青海铜铁山的天然地震探测剖面,实际路线长约２０００ｋｍ,布设了约１１０台便携地震仪,记录了数百次远震和近震事件,采用多种方法进行了资料处理与解释．依据ＳＫＳ,ＰＫＳ,ｐｓ等横波分裂特征计算的青藏高原中部上地幔的地震各向异性表明：研究区各构造单元内的地震各向异性有明显变化,发现上地幔各向异性快速波的偏振方向与造山带的走向不完全一致．在雅江缝合线、崩错－嘉黎、唐古拉山口、昆仑山口几条断裂带处南、北各向异性出现显著的差异,而金沙江缝合线和班公－怒江缝合线的南、北则没有明显的各向异性变化．由Ｐ波走时残差,利用层析技术反演了４００ｋｍ深度内的速度图像,可以看出近地表１００ｋｍ范围内速度的不均匀变化与地表划分的构造单元很吻合,进一步佐证了青藏高原是由不同时期的微板块拼合而成的认识．在青藏高原中部１５０ｋｍ深度以下发现了多处低速区．在金沙江缝合带下方约２００ｋｍ深度处有一长２５０ｋｍ以上、延伸１５０ｋｍ的低速体,推测可能是一地幔柱．利用ＰＳ转换波划分的界面,显示出青藏高原北部具有低速层和高速层交替出现的地壳结构．     

Effect of the Twin Jetties as A Regulating Structure at the Tao-er Estuary

The phase one project of the twin jetties at the Tao-er Estuary yields no effect on the flow, and there is a large area of deposition. A numerical model is employed to simulate the flow field, and the scouring and silting in the channel be-tween the two jetties are analyzed. The results show that the effective tidal flux between the two jetties is reduced due to the notch located at the heel of the east jetty, and the effect of contraction-flush is not obvious. As for the regulation of this kind of estuary under the tide action, the capability of tidal flux should be fully used.     

茂名大放鸡海域文昌鱼、蛇尾分布及其与底质粒度特征的关系

为给茂名市建设文昌鱼省级自然保护区提供基础资料,根据2003年8月～2004年5月间对茂名大放鸡海域的调查结果,对文昌鱼和蛇尾的分布特性进行了研究.结果表明:文昌鱼和蛇尾均呈集群分布,在空间分布上表现为正相关关系,不存在强烈的竞争关系.文昌鱼主要分布在中值粒径MdΦ为0.4～2.2之间砂质中.在0.5≤MdΦ＜1.5范围内,文昌鱼分布密度相对地高,而在MdΦ＜0.5或MdΦ≥1.5范围内,文昌鱼分布密度相对较低.粒径0.36～0.78 mm组分＜50%时,文昌鱼分布密度≤50 ind/m2;粒径0.36～0.78 mm组分≥50%时,文昌鱼分布密度＞100 ind/m2.蛇尾分布在中值粒径MdΦ为0.2～0.8之间砂质中.粒径 0.36～0.78 mm组分占10%～50%时,蛇尾分布密度较低,而粒径0.36～0.78 mm组分占60%～80%时,蛇尾分布密度较高.     

Spatial-temporal patterns of China’s interprovincial migration, 1985-2010

Migration plays an increasing role in China's economy since mobility rose and economic restructuring has proceeded during the last three decades. Given the background of most studies focusing on migration in a particular period, there is a critical need to analyze the spatial-temporal patterns of migration. Using bicomponent trend mapping technique and interprovincial migration data during the periods 1985-1990, 1990-1995, 1995-2000, 2000-2005, and 2005-2010 we analyze net-, in-, out-migration intensity, and their changes over time in this study. Strong spatial variations in migration intensity were found in China's interprovincial migration, and substantial increase in migration intensity was also detected in eastern China during 1985-2010. Eight key destinations are mostly located within the three rapidly growing economic zones of eastern China (Pearl River Delta, Yangtze River Delta and Beijing-Tianjin-Hebei Metropolitan Region), and they are classified into three types: mature, emerging, and fluctuant origins, while most key origins are relatively undeveloped central and western provinces, which are exactly in accordance with China's economic development patterns. The results of bicomponent trend mapping indicate that, in a sense, the migration in the south was more active than the north over the last three decades. The result shows the new changing features of spatial-temporal patterns of China's interprovincial migration that Fan and Chen did not find out in their research. A series of social-economic changes including rural transformation, balanced regional development, and labor market changes should be paid more attention to explore China's future interprovincial migration.     

中国海相碳酸盐岩层系油气地质特点、战略选区思考及需要解决的主要地质问题

中国海相碳酸盐岩层系油气资源量大,但探明程度低,是油气资源战略接替的重要领域。中国海相碳酸盐岩层系具有形成时代老、改造强烈、沉积中心与生烃中心不吻合、储层具有多样性且非均质性强、多烃源层、多期生烃、多期成藏、多期调整与改造等显著特点,与陆相碎屑岩层系有明显差别,又有别于国外海相碳酸盐岩层系。在对不同地区海相碳酸盐岩层系油气地质条件进行分析解剖的基础上,分别对四川盆地、中下扬子及滇黔桂地区、塔里木盆地、鄂尔多斯盆地、渤海湾盆地和青藏地区的海相碳酸盐岩层系油气勘探战略选区急需解决的地质问题进行了讨论。