Λ型三能级原子与对相干态光场共振作用中的非经典性质

研究了对相干态光场与一个Λ型三能级原子的共振相互作用中的各种非经典性质,例如光场的反群聚效应,Cauchy-Schwart不等式违背,光场的双模压缩性质等,并发现这些非经典性质在对原子态进行测量后将得到增强.     

第三次国土调查城镇村内部细化调查方法研究

基于第三次国土调查城镇村内部细化调查的工作要求和数据基础,梳理了城镇村调查边界划定、城镇村土地利用框架构建、城镇村土地利用图斑转绘、城镇村土地利用类型判定、外业补充调查等城镇村内部细化调查环节;归纳了1:2000基础地理信息数据、不动产登记数据、基础性地理国情监测数据等已有调查成果在各调查环节的数据转换利用方式,为城镇...     

区域数字地震台网实时速报系统研究

根据我国地震监测台网的发展趋势,提出了区域数字地震台网实时速报系统的发展目标,研究了实现这一目标应解决的实时数据流接收、震相自动识别、震相可靠性处理、实时地震定位、震相到时等值线实时绘制、地震震级的实时计算、地震动强度分布图的实时绘制等问题.我们编制了一套实时地震速报软件,实现了上述功能,并用福建数字地震台网记录的地震事件进行软件功能测试.测试结果表明:对于网内地震,软件处理结果基本达到中国地震局地震速报评比满分的要求,速报时间缩短至30～50 s.此外,通过实时仿真技术,系统可给出实际观测到的PGA、PGV、PGD等值线图,可以为应急救灾确定重灾区和有感范围提供帮助.     

中国大陆西部强震前超低频磁场时空变化特征

对2015年至2019年期间中国大陆西部的磁通门磁力仪秒采样观测资料开展了5—100 s频段的地磁垂直强度极化分析,并运用一些数学方法对分析结果进行了处理.结果显示,极化高值在经向和纬向均无明显的形态和幅值变化,且极化高值与地磁外源场扰动无关.在此基础上筛选出18次极化高值异常事件,利用插值方法得到了极化高值异常的空间...     

Asymptotic solutions of differential rotation driven by convection in rapidly rotating fluid spheres with the non-slip boundary condition

A strong Coriolis force in a rapidly rotating planet and star not only enforces two-dimensionality of fluid motion driven by thermal instabilities but also generates strong differential rotation even in the vicinity of the onset of instabilities. We derive an asymptotic solution describing convection-driven differential rotation in rotating, self-gravitating Boussinesq fluid spheres with the no-slip boundary condition, taking into account full spherical curvature and being valid for asymptotically small Ekman numbers. For the purpose of validating the asymptotic solution, the corresponding numerical analysis valid for large or small Ekman numbers is also carried out, showing a satisfactory agreement between the asymptotic and numerical solutions.     

Modeling the effects of riparian planting strategies on stream temperature: Increasing suitable habitat for endangered Formosan Landlocked Salmon in Shei‐Pa National Park,Taiwan

Reducing or stabilizing the stream temperature of ChiChiaWan Creek is a crucial work for Formosan Landlocked Salmon because ChiChiaWan Creek is the only one habitat for this endangered species. Planting trees in the riparian zone would be one of the alternatives. The purpose of this study was to evaluate the effects of several planting strategies on daily maximum stream temperature along the river. The results showed the effective vegetative shading angles should be more than 50° along ChiChiaWan Creek to reduce the direct solar radiation heating effectively. Upstream planting with 70° vegetative shading angle could be the most effective way among all the scenarios. However, this planting strategy could not improve the worst situations in summer because of the large solar elevation angles. The upstream planting in ChiChiaWan Creek was strongly recommended because the canopies could be easier to extend to totally cover the narrow width of river producing the most effective shades. Practicing the upstream planting with 90° vegetative shading angle can increase more than 1 km long suitable habitats for the endangered Salmon in summer. Alternatively, the west‐side planting scenario was the second effective way for temperature reduction. Our result provided a useful suggestion for the authorities in charge of saving the Formosan Landlocked Salmon, particularly under the stress of global warming. Copyright © 2011 John Wiley & Sons, Ltd.     

Mineral Chemistry of Clinopyroxenes in Mantle-Derived Inclusions in Cenozoic Basalts from Eastern China and Their Geological Significance

In this paper, 183 chemical analyses of clinopyroxenes are collected from mantle-derived inclusions inCenozoic basalts of eastern China. Through synthetic studies of the relevant data, their mineral chemistry andgeological significance are discussed. Based on the composition fo clinopyroxenes the authors conclude that theCenozoic upper mantle in eastern China is of the continental, primitive, metasomatic and high-temperaturetypes and is related to rift structural environment and variation in composition of basalts. The geobarometry ofclinopyroxenes indicates that Cenozoic basalts of eastern China are derived from the asthenosphere and thatthe average depth of faults progressively increases from south to north and from east to west.     

EFFECTS OF OROGRAPHY AND HORIZONTAL DIFFUSION ON THE GENERATION OF THE ASYMMETRIC MOTION IN THE BAROTROPIC FILTERED MODEL ATMOSPHERE

By utilizing the barotropic vorticity equation including effects of orography and horizontal diffusion,the linearized equations describing symmetric and antisymmetric motions and their analytic solutions are pre-sented.It can be found from the solutions that no matter what kind of motion may be,each solution consistsof three waves,namely,Rossby wave related to initial values,marching wave propagating at Rossby wavevelocity and stationary wave.The latter two are closely related to orography and horizontal diffusion.However,if the motion is symmetric at the initial instant,then the antisymmetric components of orographyand of horizontal diffusion are likely to lead to the generation of antisymmetric motion.In the steady state,the symmetric flow is connected with symmetric orography and horizontal diffusion and the antisymmetricflow with antisymmetric orography and horizontal diffusion.Further,in order to verify the above analysis,three numerical experiments have been made.The results show that antisymmetric orography can produceantisymmetric motion.Finally,the atmospheric interactions between Northern and Southern Hemispheresare discussed.     

福州地区的Q结构和它的横向不均匀性

本文利用人工爆破地震资料,在频率域中,用波组频谱比方法计算了福州地区的Q结构,结果发现:该区中地壳低速层Q值明显偏低,仅为40——80,且存在横向变化,地壳上部和下部Q均为200左右;福州盆地与永泰——梧桐地段地壳平均Q也明显偏低,且福州盆地中部Q仅120—150,为全区最低值,低Q区与温泉分布和断裂位置有良好的对应关系。     

华北东部地区上地幔运动与盆地形成关系的模拟研究

在综合分析华北东部深部构造、盆地构造及其动力学特征等资料的基础上,运用离心技术讨论了该区盆地形成机制与上地幔运动的关系。这种离心技术采用物质密度差代替温度差是一种新的实验方法。 实验结果表明,上地幔对流、上地幔隆起(或底辟)以及重力均衡作用产生了华北地壳的单向引张力,从而导致箕状盆地的形成。 作者认为,华北东部地区盆地形成和发展的动力源与上地幔的运动和重力作用密切相关