Coal Fly Ash Utilization: Low Temperature Sintering of Wall Tiles

We present here a study of the sintering of fly ash and its mixture with low alkali pyrophyllite in the presence of sodium hexa meta phosphate (SHMP), a complex activator of sintering, for the purpose of wall tile manufacturing. The sintering of fly ash with SHMP in the temperature range 925–1050 °C produces tiles with low impact strength; however, the incremental addition of low alkali pyrophyllite improves impact strength. The impact strength of composites with ⩾40% (w/w) pyrophyllite in the fly ash–pyrophyllite mix satisfies the acceptable limit (19.6 J/m) set by the Indian Standards Institute for wall tiles. Increasing the pyrophyllite content results in an increase in the apparent density of tiles, while shrinkage and water absorption decrease. The strength of fly ash tiles is attributed to the formation of a silicophosphate phase; in pyrophyllite rich tiles, it is attributed to the formation of a tridymite-structured T-AlPO4 phase. Scanning electron micrographs show that the reinforcing rod shaped T-AlPO4 crystals become more prominent as the pyrophyllite content increases in the sintered tiles

Cyclones and anticyclones in the black sea-mediterranean region

Настоящая работа посвящена исследованию режима синоптических вихрей и региональных особенностей циклонической активности в Черноморско-Средиземноморском регионе. Для этого использовались ряды характеристик синоптических вихрей (циклонов и антициклонов), полученные по ежедневным данным реанализа NCEP/NCAR о высоте геопотенциала за 1948 – 2006 гг. Для верификации полученных данных привлекались данные спутниковых наблюдений EUMETSAT за период 1996 – 2009 гг. Определение параметров облачности и циклонов на основе информации со спутников Meteosat 2 – Meteosat 8, передаваемой в видимом и инфракрасном диапазонах, выполнялось с помощью специализированного про-граммного обеспечения, созданного в МГИ НАН Украины. В результате информация о циклонической активности в Чер-номорско-Средиземноморском регионе была уточнена спутниковыми данными. С использованием кластерного анализа было выполнено климатическое районирование Средиземноморского региона и выделены шесть характерных зон цикло-генеза, для которых определены типичные параметры облачности и циклонов.This study is dedicated to the analysis of the regime of synoptic vortices and regional features of cyclonic activity in the Black Sea-Mediterranean region. Time series of characteristics of synoptic vortices’ (cyclones’ and anticyclones’) were calculated using daily NCEP/NCAR re-analysis data sets on geopotential height in 1948 – 2006. For the verification of the obtained data satellite information from EUMETSAT in 1996 – 2009 was involved. Assessment of the parameters of cloudiness and cyclones on the basis of Meteosat 2 – Meteosat 8 satellite data sets in visible and IR range was done using the special software package created in the MHI NASU. As a result, cyclonic activity in the Black Sea-Mediterranean region was refined using satellite data. On the basis of cluster analysis, climatic regionalization of the Mediterranean cyclogenesis was done. In the result, six typical zones of cyclo-genesis were identified. Typical values of cyclones’ and cloudiness’ parameters were estimated

Coal fly ash utilization: Low temperature sintering of wall tiles.

We present here a study of the sintering of fly ash and its mixture with low alkali pyrophyllite in the presence of sodium hexa meta phosphate (SHMP), a complex activator of sintering, for the purpose of wall tile manufacturing. The sintering of fly ash with SHMP in the temperature range 925–1050 °C produces tiles with low impact strength; however, the incremental addition of low alkali pyrophyllite improves impact strength. The impact strength of composites with ⩾40% (w/w) pyrophyllite in the fly ash–pyrophyllite mix satisfies the acceptable limit (19.6 J/m) set by the Indian Standards Institute for wall tiles. Increasing the pyrophyllite content results in an increase in the apparent density of tiles, while shrinkage and water absorption decrease. The strength of fly ash tiles is attributed to the formation of a silicophosphate phase; in pyrophyllite rich tiles, it is attributed to the formation of a tridymite-structured T-AlPO4 phase. Scanning electron micrographs show that the reinforcing rod shaped T-AlPO4 crystals become more prominent as the pyrophyllite content increases in the sintered tile