Cyclotron wave instability in the corona and origin of solar radio emission with fine structure

The longitudinal waves (Bernstein modes and plasma waves near the hybrid frequency) in a mixture of equilibrium coronal plasma and a small group of energetic electrons are investigated. The energetic electrons have a nonequilibrium momentum distribution inherent in trapped particles. The frequency dependence of the cyclotron instability increments is studied. Attention is paid to a significant role of the relativistic effects for the cyclotron instability of longitudinal waves. For sufficiently large velocity of nonequilibrium electrons the increments are shown to increase when the hybrid frequency coincides with one of the gyrofrequency harmonics (double plasma resonance). The results obtained are used in Parts II and III to explain tadpoles and zebra-pattern in solar radio bursts.     

近几十年我国极端气温变化特征分区方法探讨

采用聚类统计检验分析和旋转主分量分析相结合确定中心站的方法,利用我国多年极端气温资料,对我国最高和最低气温年际变化型态进行区划。结果表明,这两种方法结合可以互相补充,使分区结果更具客观性。中国极端高温和极端低温年际变化分别可划为12和11个不同类型的区域,分别计算了各区域第一主成分的方差贡献率以及各区域之间的两两相关系数,检验证明分区是合理的。     

Mudstone lithogeochemistry and formation conditions of Vendian deposits in the Shkapovo-Shikhan Basin

Variation of geochemical modules and indices in mudstones from the Upper Vendian Kairovo and Shkapovo groups of the Shkapovo-Shikhan Basin provides the comprehensive information on changes in maturity of the fine aluminosiliciclastic material delivered in the basin, characterizes the redox environment in bottom water, and makes it possible to reconstruct the rock composition in provenance and its evolution through time. The generally moderate maturity of the fine terrigenous clastic material suggests that a nearly semiarid-semihumid climate dominated in paleodrainage area throughout the Late Vendian. It has been established that reducing environment did not exist in bottom water of the central Shkapovo-Shikhan Basin throughout the Late Vendian. Intermediate rocks prevailed in the paleodrainage area. More silicic rocks could occur only in the early Staropetrovo and late Salikhovo times. Data points of mudstones from the Kairovo and Shkapovo Groups plotted on the Cr-Ni, Co-V, Co/Hf-Ce/Cr, La-Th, and La/Sm-Sc/Th diagrams indicate that both Archean and more mature Paleoproterozoic crustal blocks existed in different proportions in the Late Vendian within source areas.     

An iterative method for the construction of equilibrium N-body models for stellar disks

One widely used technique for the construction of equilibrium models of stellar disks is based on the Jeans equations and the moments of velocity distribution functions computed using these equations. Stellar disks constructed using this technique are shown to be “not entirely” in equilibrium. Our attempt to abandon the epicyclic approximation and the approximation of infinite isothermal layers, which are commonly adopted in this technique, failed to improve the situation substantially. We conclude that the main drawback of techniques based on the Jeans equations is that the system of equations employed is not closed and, therefore, requires adopting an essentially ad hoc additional closure condition. A new iterative approach to constructing equilibrium N-body models with a given density distribution is proposed. The main idea behind this approach is that a model is first constructed using some approximation method, and is then allowed to adjust to an equilibrium state with the specified density distribution—if necessary, with the required parameters of the velocity distribution remaining fixed in the process. This iterative approach was used to construct isotropic, spherically symmetric models and models of stellar disks embedded in an external potential. The numerical models constructed prove to be close to equilibrium. It is shown that the commonly adopted assumption that the profile of the radial-velocity dispersion is exponential may be wrong. The technique proposed can be applied to a wide range of problems involving the construction of models of stellar systems with various geometries.     

青藏高原植物形态和解剖适应性研究进展

与低海拔地区相比，青藏高原的太阳辐射、水分条件、氧分压、气温等环境条件都有明显差异，青藏高原的植物在细胞壁厚度、栅栏细胞层数、通气组织大小、异细胞数量和分布、表皮附属物类型等方面与低海拔地区的相比也有较大的不同。综述了在青藏高原特殊的生态条件下，植物在形态和解剖方面的适应性表现，分析了该领域目前的研究特点和存在的一些问题，并在全球环境变化背景下，对其发展前景进行了展望，指出了未来的发展趋势。     

福建平潭虎潮山滑坡成因机理分析与评价

虎潮山滑坡位于平宏公路12k 704~12k 884段北侧山坡体上,是平潭海岛通往陆地的唯一公路通道。论文通过定性的工程地质分析和定量计算评价了虎潮山坡体稳定性的变化趋势,提出改建公路超挖深切坡脚和持续长时间强降雨导致的孔隙水压力作用是边坡发生滑动破坏的主要因素。     

Gzhelian fusulinids first discovered in central Iran

Gzhelian deposits established in Iran for the first time are described. They rest with a considerable hiatus on the Moscovian deposits constituting, along with Asselian strata, an integral carbonate succession of the Zaladu Formation in eastern Iran. The Zaladu Formation is correlative with the Vazhnan Formation of the Abadeh region (central Iran) and the Dorud Formation of the Elburz (Alborz) Mountains. An assemblage of Gzhelian fusulinids from the studied section is well comparable with the assemblage of the Ultradaixina bosbytauensis Zone distinguished in the uppermost Gzhelian of the Darvaz, Fergana, the Southern Urals, Donetsk Basin, and Carnic Alps. Two new species of the genus Schellwienia (Sch. anarakensis and Sch. stocklini) are described. Gzhelian and Asselian fusulinids found in the section are figured in two paleontological plates.