The lunar Late Heavy Bombardment (LHB) defines a time between ∼3.8 to possibly 4.1 Gy ago when the Nectarian and early-Imbrium basins on the Moon with reasonably well-constrained ages were formed. Some have argued that these basins were produced by a terminal cataclysm that caused a spike in the inner Solar System impactor flux during this interval. Others have suggested the basins were formed ...

شرایط افروزش و اشتعال سوخت‌های گداخت هسته‌ای در حضور ناخالص­‌ها، یکی از موارد مهمی است که طراحی قرص‌های سوخت باید مورد توجه قرار گیرد. این مقاله اثر ناخالصی هسته سنگین طلا بر کلیه فرایندهای احتراق پلاسمای غیرتعادلی دوتریم- تریتیم مدل چهار دمایی آن شکل تابع توزیع انرژی رفتار فوتون‌ها تأثیر می‌گذارد بررسی گرفته است. مطالعه شامل اثرات منفی سوخت، طول زمان تشکیل لکه داغ نتایج محاسبات عددی به­ دست آم...

The proposal that climate change can drive the uplift of mountain summits hinges on the requirement that glacial erosion significantly enhances the relief of a previously fluvially sculpted mountain range. We have tested this hypothesis through a systematic investigation of neighbouring glaciated and nonglaciated drainage basins on the eastern side of the Sierra Nevada, CA. We present a simple,...

The landforms and landscapes discussed in this book developed in a variety of terrains, which together express the diversity of the geological background of the Brazilian territory. Located essentially in the old and relatively stable nucleus of the South American plate (known as the South American platform), Brazil comprises seven major categories of tectonic units, which are as follows: crato...

Early–Middle Pennsylvanian (late Carboniferous) age coalbearing strata in Europe can be found in two general depositional settings (OPLUŠTIL & CLEAL, 2007; CLEAL et al., 2010, 2011). The most extensive deposits were formed in paralic settings, most notably on the Variscan Foreland and associated basins between the British Isles and northern Turkey, in the Donets Basin of eastern Europe, and the...

Hydraulic jump on adverse stilling basin is an unstable phenomenon which causes some complexities in controlling of the   jump. This paper considers the stability of free hydraulic jump on adverse stilling basins from a theoretical point of view. A minimum value of upstream Froude number is needed to produce the free hydraulic jump on adverse stilling basins which was presented by a theoretical...

Pre-sedimentation basins are among the most important elements of the conventional water treatment process. In pre-sedimentation basins, due to different velocity gradients, secondary and rotational flows are formed that will create short paths and increase dead and still flow zones as well as changes in the flow mixing. This will prevent laminar flow conditions for sedimentation and will reduc...

This paper explores the applicability of flood impact databases in the flood risk governance process. This study begins with a twofold analysis of three hydrographical basins: one analysis based on the data of a recently constructed flood-impact database for Portugal and another based on selected socioeconomic and biophysical variables that characterize the basins’ territorial context. From the...

In this paper we show that there is an analytic and computable dynamical system with a hyperbolic sink s such that the basin of attraction of s is not computable. As a consequence, the problem of determining basins of attraction for analytic hyperbolic systems is not, in general, algorithmically solvable. 1 Summary of the paper Dynamical systems are fascinating mathematical objects. They can be...