The Airshed for Ozone and Fine Particulate Pollution in the Eastern United States

— To examine the spatial scales associated with atmospheric pollutants such as ozone (O₃) and fine particulate matter (PM_2.5), we employ the following five techniques: (1) Analysis of the persistence of high O₃ concentrations aloft; (2) spatial and lag correlations between the short-term components (i.e., weather-induced variations) in the time series of O₃ and PM_2.5 throughout the eastern United States; (3) analysis of mixed-layer forward trajectories compiled at different locations on a climatological basis to identify the potential region covered in 1-day of atmospheric transport; (4) analysis of three-dimensional Lagrangian trajectories of tracer particles for three high-O₃ episode events in the summer of 1995; and (5) analysis of the spatial extent over which emissions have an impact through photochemical model simulations. Regardless of the method chosen, the results demonstrate that pollutants such as O₃ and PM_2.5 have the potential to affect regions having spatial scales of several hundred kilometers. This finding has implications to regulatory policies for addressing the pollution problem, and for optimally designing monitoring networks for such pollutants.     

水平电偶极子在三层媒质中激发的电磁场特征的数值研究

将空气及地面以下两层视为三层有耗散的线性媒质，求出第三层中的水平偶极子激发的电磁场在地表处的积分形式解，进行数值计算，分析其频谱特征。结果表明电磁辐射异常的优势频率为0～2Hz，与实际观测资料相吻合，在超低频或甚低频，有比较明显的电磁场异常。并讨论其对地震电磁辐射监测的指导意义。     

1920年12月16日海原8.5级大地震的伤亡人口再评估

本文重新整理了 192 0年海原 8 5级地震的历史资料 ,归纳出关于该地震死亡人口和直接经济损失有关的 6种重要基础资料 ,并对它们的可靠性和完整性作了分析评估。在此基础上 ,为了做进一步的相互补充和印证 ,对该次大地震重新进行了灾害评估。认为该次大地震共死亡 2 7346 5± 970 0人 ,较为可靠 ;压死牲畜 110 4 0 6 8± 76 0 0 0头 ,可供参考 ;只有 4 1个县提供了倒塌房屋的可靠数字 ,总计为 5 90 6 35间。因此 ,倒塌房屋的实际数可能远大于此数。     

THE EFFECTS OF TURBULENT BURSTING ON THE SEDIMENT MOVEMENT IN SUSPENSION

~~THE EFFECTS OF TURBULENT BURSTING ON THE SEDIMENT MOVEMENT IN SUSPENSION@Ye MAO$Hohai University!Nanjing 210098 China~~     

西北干旱区城市土地利用变化及其区域生态环境效应——以甘肃河西地区为例

基于高分辨率土地利用/土地覆盖数据,本文对1985～2000年期间河西地区城市土地利用变化的区域生态环境效应进行了定量分析,结果表明:1)1985～2000年期间河西地区总体生态环境质量在一定程度上维持着相对稳定,但生态环境质量改善和恶化的两种趋势并存,并在县级行政单元上表现出明显的区域分异特征,城市用地变化对区域生态环境的影响总体而言不显著;2)整个河西地区城市用地增长缓慢,表明其城市化进程缓慢.与城市用地变化有关的土地利用类型也多分布在金昌、嘉峪关、张掖、武威和酒泉5个地级市所在地区,表明这些区域的城市化过程相对活跃;3)城市用地变化对生态环境影响的空间规律表现为:使生态环境原本较差的地区生态环境质量有所增加,而使生态环境质量较好的地区生态环境质量降低;4)城镇用地与工矿用地对区域生态环境的影响表现出与城市用地总体基本一致的规律,但农村居民点则对生态环境正、负两方面影响都较为显著;5)城市用地扩展对区域生态环境的影响也体现出与城市用地总体类似的区域分异特征;而城市用地收缩的影响则与此趋势相反.     

Cenozoic Volcanism in South China Sea and Its Vicinity and South China Sea Spreading

The rock series, rock types and Sr-Nd isotopic dating of the Cenozoic volcanic rocks in the South China Sea are similar to those in its vicinity. On the basis of the spreading age of the South China Sea, the Cenozoic volcanic rocks are divided into three stages: the pre-spreading stage, the spreading stage and the post-spreading stage. The deep process characteristics of the asthenosphere and lithosphere may be inferred from the study on primary basaltic magma. The top layers of the asthenosphere both in the spreading stage and in the pre-spreading stage are closer to the earth surface than that in the post-spreading stage. From the pre-spreading stage to the spreading stage, the top layer of the asthenosphere decreased in depth, while the amount of interstitial partial melts increased. The evolution of the primary basaltic magma shows a progressive evolution sequence of the rifting volcanism and a faster lithospheric spreading velocity. From the spreading stage to the post-spreading stage, the top layer of the asthenosphere gradually increased in depth, but the amount of interstitial partial melts decreased. The evolution of primary basaltic magma shows a retrogressive evolution sequence of the rifting volcanism and a gradual decrease in the lithospheric spreading velocity. The depth recognized by the study on the Cenozoic volcanism demonstrates the deep environment for the formation and evolution of the South China Sea.     

胶东金矿形成期间地幔流体参与成矿过程的碳氧氢同位素证据

胶东地区发育有两种类型的金矿床，以玲珑，焦家，三山岛，乳山为代表的石英脉型-破碎蚀变岩型和以大庄子，蓬家夼为代表的胶莱盆地北缘滑脱破碎带内的角砾岩型金矿，本文选择了两种类型中的玲珑，三山岛和大庄子金矿床进行碳氧氢同位素测定。初步认为两类金矿属于同一成矿系统，它们形成于120Ma左右的华北克拉通岩石圈减薄和软流圈上涌期间，岩浆流体和地幔脱气与胶东世界级金矿的形成密切相关，在石英脉型-破碎蚀变岩型矿石中可见深刻的地幔流体和岩浆流体的“烙印”。形成于滑脱破碎带中的角砾岩金矿流体与中生代大气降水和海相碳酸盐岩发生了强烈的交换作用。     

根据土壤化学特征划分伏牛山亚热带北界

The boundary between subtropical zone and temperate zone is not only important in physical geography, but also attractive in agricultural production. Seven soil profiles studied in this paper are placed along the southern slope of Funiu Mountain at different heights above sea level.Many compositions and properties of these soils have been determined in laboratory. In this paper,the laws of migration and accumulation of soil materials on the southern slope of Funiu Mountain are discussed first, then the division of the boundary between subtropical zone and temperate zone in this area according to soil geochemistry is discussed with qualitative methods and mathematical classification method in which twelve selected indexes such as Km, Saf, Ba, β, Feo/Fet, Mno/Mnt and so on are used. The result indicates that the boundary between subtropical zone and temperate zone on the southern slope of Funiu Mountain is about 950 m above sea level.     

网络RTK基准站间基线单历元模糊度搜索方法

提出一种网络RTK的基准站（一般相距几十公里或上百公里）单历元双差模糊度搜索方法，并详细地给出该方法的数学模型、方法步骤与数据检验结果。该方法的主要思想为：使用双频GPS载波相位数据，不需解算双差观测方程组，直接利用测站坐标已知、模糊度为整数和双频模糊度之间存在线性关系这3个条件，对基准站的双差整周模糊度进行搜索。特点为快速、简单、实用、不受周跳影响，只需1个历元便可确定双差整周模糊度。