Microstructure mechanism map of dynamically recrystallized marble     

Stanislav Ulrich  Alan B. Thompson  Karel Schulmann  Martin Casey   《Tectonophysics》2006,412(3-4):173-182

The relative nucleus density (RND) model of dynamically recrystallized grain size [Sakai, T., Jonas, J.J. 1984. Dynamic recrystallization: mechanical and microctructutal consideration. Acta metallurgica, 32, 198–209] was applied to experimentally and to naturally deformed marbles that have undergone dynamic recrystallization. The model shows that a relationship between initial grain size (D₀) and stable dynamically recrystallized grain size (D_S) for a given value of temperature-corrected strain-rate (Z) controls grain size evolution during dynamic recrystallization. New microstructural mechanism maps (MM-maps) for experimentally and naturally deformed marbles (based on previously published data) were defined in log grain size–log Z space and show two distinct regions of grain reduction and grain coarsening. The boundary between these two regions corresponds to an equation relating dynamically recrystallized grain size and temperature corrected strain rate, as proposed in this work. The new MM-map was used to trace semi-quantitatively microstructural and grain size evolution in naturally deformed marbles that underwent dynamic recrystallization at different thermal conditions. The boundary between grain coarsening and grain reduction does not necessarily coincide with the boundary between rotation and migration recrystallization mechanisms. Assessment of available natural data shows that the boundary condition D₀ = 2D_S between grain-coarsening and grain-reduction introduced by Sakai and Jonas [Sakai, T., Jonas, J.J. 1984. Dynamic recrystallization: mechanical and microctructutal consideration. Acta metallurgica, 32, 198–209] is not required for naturally deformed marble.  相似文献   

LUKANGA SWAM: PROBABLY ASTROBLEME     

Stanislav Vrna 《Meteoritics & planetary science》1985,20(1):125-140

This article summarizes information relevant to the interpretation of Lukanga Swamp — a depression some 52 km in diameter in central Zambia — as a considerably eroded astrobleme. The results of reconnaissance geological mapping, an airborne magnetic survey and petrological study of a small set of samples of impact rocks are presented. Circular topographic features coincide with a remarkably subdued magnetic field. A circular set of tangential faults indicates a diameter of the outer rim approximately 110 km. Polymict breccia occur, carrying marble megaclasts (klippes) up to 50 m long. Strongly shocked quartz clasts with several sets of decorated planar features are present as well as devitrified, flow-banded silica glass exhibiting decarbonation textures around marble clasts. Provisional correlation of the brecciation event with the local geological record suggests a Paleozoic age of the astrobleme.  相似文献   

<Superscript>40</Superscript>Ar/<Superscript>39</Superscript>Ar dating of the stage of transform-shear deformation in evolution of the early Caledonides in western Sangilen,southeastern Tuva     

N. V. Barabash  V. G. Vladimirov  A. V. Travin  D. S. Yudin 《Doklady Earth Sciences》2007,414(1):592-598

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Star and polyline glyphs in a grid plot and on a map display: which perform better?     

Tomasz Opach  Stanislav Popelka  Jitka Dolezalova  Jan Ketil Rød 《制图学和地理信息科学》2018,45(5):400-419

Glyphs are small geometric shapes that in geovisualization are often used to represent multidimensional spatial data. The aim of this study is to investigate the effectiveness of their two types – star and polyline glyphs, as they can encode the same message and can provide similar functionality. Thus, if the two glyph types are similar and can be used for the same data, the question arises as to which of them better facilitates various user tasks. To address this question, an empirical study of 26 individual users is conducted to investigate differences in user performance for polyline and star glyphs shown either in a grid plot or on a map display. In this study, a task-based approach with eye-tracking is applied, as well as a subjective questionnaire and a psychological test of cognitive style. The finding is that polyline glyphs better facilitate tasks when datapoint values in glyphs are to be read, whereas star glyphs are better when a visual search among glyphs is to be done. Moreover, the results reveal that the map display works better than the grid plot. If star glyphs are to be used, the key (legend) needs to be better incorporated into a visual interface.  相似文献   

Dr. Oldřich Kostka *1924 †1960     

Stanislav Brandejs 《Studia Geophysica et Geodaetica》1961,5(1):94-94

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“Sigma-1” Measuring Complex for the Investigation of Small-Scale Characteristics of Hydrophysical Fields in the Upper Layer of the Sea     

A. S. Samodurov  V. Z. Dykman  V. A. Barabash  O. I. Efremov  A. G. Zubov  O. I. Pavlenko  A. M. Chukharev 《Physical Oceanography》2005,15(5):311-322

We describe a new measuring complex aimed at the investigation of small-scale processes in the upper active layer of the sea. The necessity of creation of a complex of this sort is justified and a circle of problems that can be solved with the help of this complex is described. The scales of resolution of horizontal and vertical inhomogeneities in measuring in the mode of vertical probing are theoretically estimated. The basic technical characteristics of the complex are presented. We also present the results of laboratory and field tests, which confirm the agreement between the calculated and actual technical possibilities of the complex. The structural features of various versions of the “Sigma-1” measuring complex (the “Sigma-1P” point-to-point-operation version and the “Sigma-1Z” probing version) are described. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 60–71, September–October, 2005.  相似文献   

圣彼得堡土地利用格局现状特征及形成机制   总被引：1，自引：0，他引：1  

李晓玲  修春亮  ШендрикАлександрВладимирович  ЛачининскийСтаниславСергеевич  贺红士 《地理科学》2017,37(9):1382-1391

以圣彼得堡市为例,依据1948、1987和2016年土地利用数据计算居住、工业和商业用地的区位熵值并分析其变化,基于统计小区、圈层式及扇形分布3个视角,运用GIS分析计划与市场经济影响下的城市用地空间分布特征。研究结果表明,居住、工业和商业用地的空间分布规律不同：① 3类用地在城市整体空间分布中均表现出一定的分散特征,其中,居住用地空间分布表现最为分散,工业用地呈现出分区域性布局特征,相比而言商业用地空间聚集程度最高;② 商业用地在核心圈层处于主导地位,工业用地在老城区圈层为主导地位,居住用地在近郊区圈层为主导地位,远郊区圈层仍处于初步发展阶段,城市景观发展尚未成熟;③ 对比圈层式和象限式结构各类用地区位熵值分布结果,提出圣彼得堡市3类用地空间分布扇形结构特征明显,说明沿主要交通线路是现代城市用地空间扩展主要方式,其中工业用地在城市空间分布中占据更为有利的交通区位优势,居住用地次之,商业用地在城市中心区域中分布不足。圣彼得堡城市用地空间分布形成主要机制总结为以下5个方面：前苏联时期城市用地空间结构主要框架的保持;行政区划调整为城市用地结构改善提供了路径;市场经济下住房体制改革推进了城市居住郊区化;土地市场对土地功能置换进程作用较弱;产业转型缓慢导致老城区仍主要为生产中心。  相似文献   

A model of diffusion produced by a cellular surface flow     

Ruzmaikin  Alexander  Molchanov  Stanislav A. 《Solar physics》1997,173(2):223-231

A model of diffusion induced by the joint action of random cells of two different sizes (granulation and supergranulation) is developed. The basic properties of the model are defined by the dimensionless ratio = (the life time)/(characteristic size/velocity) constructed for these two types of cells. An analytical expression for the diffusivity as a function of is derived. It is estimated that for the standard parameters used the contribution of granulation to the joint diffusion is small. A comparison between the model and numerical simulations of the kinematic diffusion of magnetic fields on the solar surface is made.  相似文献   

Assessment of the effects of urban and industrial development on water and sediment quality of the Drenica River in Kosovo     

Fatbardh Gashi  Stanislav Frančišković-Bilinski  Halka Bilinski  Leutrim Kika 《Environmental Earth Sciences》2016,75(9):801

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Contamination assessment of ecotoxic metals in recent sediments from the Ergene River,Turkey     

Sari Erol  Cukrov Neven  Frančišković-Bilinski Stanislav  Kurt Mehmet Ali  Halli Mihri 《Environmental Earth Sciences》2016,75(13):1051

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