承受周期性内压的Kelvin固体厚壁球壳

将经典弹性力学里有名的Ｌａｍé问题之一,推广到粘弹性介质的情形．取位移为基本未知量,求解了这个粘弹性力学边值问题,获得位移场、应变场和应力场的公式．     

Earthquake swarms and local crustal spreading along major strike-slip faults in California

Earthquake swarms in California are often localized to areas within dextral offsets in the linear trend in active fault strands, suggesting a relation between earthquake swarms and local crustal spreading. Local crustal spereading is required by the geometry of dextral offsets when, as in the San Andreas system, faults have dominantly strike-slip motion with right-lateral displacement. Three clear examples of this relation occur in the Imperial Valley, Coso Hot Springs, and the Danville region, all in California. The first two of these areas are known for their Holocene volcanism and geothermal potential, which is consistent with crustal spreading and magmatic intrusion. The third example, however, shows no evidence for volcanism or geothermal activity at the surface.     

Focal mechanism of earthquakes in the Kamchatka-Commander region and heterogeneities of the active seismic zone

Summary Focal mechanisms of 74 shallow and 16 intermediate earthquakes (1964–1970) in the Kamchatka-Commander region are discussed. Regional stress systems and the nature of faulting are analyzed. Complex stress fields in the Kamchatka-Commander region and variable aftershock processes of strong Kamchatka earthquakes show the existence of heterogeneities of the active seismic zone in the Region.     

Integrative stochastic model standardization with genetic algorithm for rainfall pattern forecasting in tropical and semi-arid environments

ABSTRACT

Climate patterns, including rainfall prediction, is one of the most complex problems for hydrologist. It is inherited by its natural and stochastic phenomena. In this study, a new approach for rainfall time series forecasting is introduced based on the integration of three stochastic modelling methods, including the seasonal differencing, seasonal standardization and spectral analysis, associated with the genetic algorithm (GA). This approach is specially tailored to eradicate the periodic pattern effects notable on the rainfall time series stationarity behaviour. Two different climates are selected to evaluate the proposed methodology, in tropical and semi-arid regions (Malaysia and Iraq). The results show that the predictive model registered an acceptable result for the forecasting of rainfall for both the investigated regions. The attained determination coefficient (R²) for the investigated stations was approx. 0.91, 0.90 and 0.089 for Mosul, Baghdad and Basrah (Iraq), and 0.80, 0.87 and 0.94 for Selangor, Negeri Sembilan and Johor (Malaysia).     

Scaling of thermodynamic mixing properties in garnet solid solutions

 The volumes and enthalpies of mixing, ΔV ^Mix and ΔH ^Mix, of binary solid-solution aluminosilicate garnets have been studied by computer simulation. The use of “average atoms” to simulate solid solution was found to give results that are considerably different from those obtained by calculating and averaging over many configurations of cations at a given composition. Although we expect mineral properties calculated from model calculations to be correct only on a qualitative rather than a quantitative scale, fair agreement with experiment was obtained where carefully tested potential parameters were used. The results show that mixing behaviour in these materials is controlled by local strain and relaxation effects resulting from the atomic size mismatch of the mixing divalent cations. In particular, ΔV ^Mix and ΔH ^Mix are shown to scale quadratically with the volume difference between the end members, and to vary essentially symmetrically with composition, with a moderate dependence on the degree and nature of cation order. We conclude that computer modelling should be useful in providing detailed qualitative information about the mixing properties of solid solutions, which can help to better constrain and interpret experimental results. Received: 8 March 2000 / Accepted: 1 October 2000     

THE NONLINEAR PERIODIC SOLUTION OF INERTIAGRAVITATIONAL WAVE IN STRATIFIED ATMOSPHERE

In the stratified atmosphere in which the moment nondivergent approximation was applied,introducingthe nonlinear term because of the nonhomogcneous spatial distribution of density and assuming the solutionto be of the form of progressive wave,we obtain a two-order nonlinear system.By means of this system,allresults which were derived by Liu et al.(1984)were obtained.Moreover,it can be proved that there existedperiodic solution in the nonlinear systems when there existed periodic solution in the one-order approxima-tion system,and some mathematic problems arising from series expansion were avoided.In this paper,aseries of approximate solutions of nonlinear system is also discussed.     

硼氧酸盐水溶液化学

本文从硼氧酸盐水溶液中硼氧配阴离子的存在形式，盐卤硼氧酸盐化学和现代谱学方法对硼氧酸盐的研究等方面进行了综述。