PVC-U携砾过滤器滤料厚度与阻砂性的相关关系试验研究

针对第四系覆盖层、粉细砂地层成井中存在的问题,结合携砾过滤器的研制,试验并探讨了滤料层厚度与阻砂性的相关关系,初步得出了不同规格滤料理论最小阻砂厚度值。     

Parameters of Coseismic Reverse‐ and Oblique‐Slip Surface Ruptures of the 2008 Wenchuan Earthquake,Eastern Tibetan Plateau

Abstract: On May 12th, 2008, the Mw7.9 Wenchuan earthquake ruptured the Beichuan, Pengguan and Xiaoyudong faults simultaneously along the middle segment of the Longmenshan thrust belt at the eastern margin of the Tibetan plateau. Field investigations constrain the surface rupture pattern, length and offsets related to the Wenchuan earthquake. The Beichuan fault has a NE-trending right-lateral reverse rupture with a total length of 240 km. Reassessment yields a maximum vertical offset of 6.5±0.5 m and a maximum right-lateral offset of 4.9±0.5 m for its northern segment, which are the largest offsets found; the maximum vertical offset is 6.2±0.5 m for its southern segment. The Pengguan fault has a NE-trending pure reverse rupture about 72 km long with a maximum vertical offset of about 3.5 m. The Xiaoyudong fault has a NW-striking left-lateral reverse rupture about 7 km long between the Beichuan and Pengguan faults, with a maximum vertical offset of 3.4 m and left-lateral offset of 3.5 m. This pattern of multiple co-seismic surface ruptures is among the most complicated of recent great earthquakes and presents a much larger danger than if they ruptured individually. The rupture length is the longest for reverse faulting events ever reported.     

基于多源数据融合方法的中国1 km土地覆盖分类制图

精确的全球及区域土地覆盖数据是陆地表层过程研究的重要基础。在集成研究兴起和多种数据并存的背景下,利用多源信息融合技术进行大尺度土地覆盖制图具有重要的现实意义。证据理论清楚地表达了由于不确定和不完全信息所带来的对命题认识的“无知”,能够确定相应的假设在目前的认知与知识状态下的确定、不确定和“无知”程度,是多源数据决策融合的重要方法。基于证据理论,将2000年中国1∶10万土地利用数据、中国植被图集（1∶100万）的植被型分类、中国1∶10万冰川图、中国1∶[KG-*2]100万沼泽湿地图和MODIS 2001年土地覆盖产品（MOD12Q1）进行了融合,最终基于最大信任度原则进行决策,产生了新的、IGBP分类系统的2000年中国土地覆盖数据。新的土地覆盖数据在保持了中国土地利用数据的总体精度的同时,补充了中国植被图中对植被类型及植被季相的信息,更新了中国湿地图,增加了中国冰川图最新信息,使分类系统更加通用。     

云凝结物平流输送对降水云系发展影响的数值模拟研究

大气动力学中"平流输送"是非常重要的宏观动力学过程,云凝结物的平流输送与降水云系的发展演变密切相关,它把宏观动力过程与各种云凝结物粒子的时空演变联系起来,云凝结物的平流输送可以增加或减少局地大气中云凝结物的含量,改变云凝结物的空间分布状况,影响云凝结物的微观物理过程,进而促进或抑制降水云系的发展演变.本文在数值模拟研究中.通过改变云凝结物平流输送的状况来研究宏观动力过程对云微观物理过程的影响,因而利用ARPS模式开展3个分别排除云凝结物水平平流输送、垂直平流输送和三维平流输送的敏感试验,进行关于云凝结物平流输送对降水云系发展演变影响的敏感性数值模拟研究.结果表明,云凝结物的平流输送对水汽比湿的影响很小.云凝结物的三维平流输送有利于增加降水云系中雪和霰的混合比含量,抑制云水、雨水和云冰混合比含量的增长.云凝结物的水平平流输送可以降低降水云系中云水和雨水的混合比含量,增加云冰和雪的混合比含量;云凝结物垂直平流输送的作用是增加降水云系中雨水、雪和霰的混合比含量,减少云与冰混合比含量.云凝结物三维平流输送效应的分析表明,云凝结物的三维平流输送主要通过调整云凝结物的微物理过程源汇项以及降水粒子(雨水、雪和霰)的下落末速项来改变降水云系中云凝结物的垂直结构;另外,雪的三维平流输送对雪本身的分布也有一定影响.     

Analyses of dry intrusion and instability during heavy rainfall event occurred in Northern China

The 1°×1° National Center for Environmental Prediction/National Center for Atmospheric Research （NCEP/NCAR） data and mesoscale numerical simulation data are analyzed to reveal a mechanism for the formation of heavy rainfall in Northern China; this mechanism is the non-uniformly saturated instability induced by a dry intrusion. The dry intrusion and the accompanying downward transport of air with a high value of potential vorticity （PV） are maintained during the precipitation event. As the dry air intrudes down into the warm and moist sector in the lower troposphere, the cold, dry air and the warm, moist air mix with each other, and, as a result, the atmosphere becomes non-uniformly saturated. On the basis of this non-uniform saturation, a new Brunt-Vaisaila frequency （BVF） formula is derived and applied to the precipitation event. It is shown that, compared to the conditions of either a dry or a saturated atmosphere, the BVF in a non-uniformly saturated, moist atmosphere （BVF） may be more appropriate for depicting the atmospheric instability in rainy regions.     

Linking health and productivity impacts to climate policy costs: a general equilibrium analysis

Much of the debate on global climate change has focused on direct costs of mitigation. Recently this debate has included the issue of ancillary benefits. The present analysis incorporates a linkage between air pollution and ancillary health benefits into a general equilibrium model applied to Sweden. Direct disutility and indirect health effects are modelled using concentration-response and contingent valuation data. Health benefits are compared in three scenarios for attaining the Swedish carbon dioxide target with alternative projected and harmful emission levels. Results show that the costs of climate policy could be overstated when not accounting for ancillary health benefits.     

汶川地震滑坡崩塌的空间分布特征

汶川地震发生在青藏高原东部边界的龙门山断裂带.该区域由一系列叠瓦状冲断带构成,在大地构造上是连接青藏高原与扬子地台的过渡地带.此次地震引发了大规模的滑坡、崩塌、碎屑流等地质灾害,造成严重的人员伤亡和社会经济财产损失.震后的凋查和研究结果表明,在龙门山断裂带的两侧,滑坡崩塌灾害的分布很不均匀.大多数的滑坡崩塌存在于龙门山...     

汶川8.0级地震小鱼洞地表破裂带古地震事件的光释光测年

小鱼洞地震地表破裂带罗元村探槽剖面揭示了汶川8.0级大地震之前的1次同等规模的古地震事件.文中对采自小鱼洞破裂带罗元村古地震探槽的7个冲洪积物样品进行了细颗粒石英简单多片再生法和单测片再生法光释光测年研究.LED08-212样品SAR法预热坪实验表明预热温度坪区间为180～240℃,在此温度下热转移量小于等效剂量的1%...     

氢化物发生——原子荧光光谱法测定温泉水样中的砷、锑

使用AFS - 820双道原子荧光光度计,运用氢化物发生——原子荧光光谱法同时测定了腾冲火山区的大滚锅、叠水河两温泉各水样中的微量元素As、Sb,研究探讨了同时测定两种元素过程中的仪器最佳条件设置.在21天的连续采样检测中,每天绘制标准曲线相关系数RAs≥0.999 6,Rsb≥0.999 5,检测结果为:大滚锅水样A...