in the present work, high temperature tensile properties of medium density polyethylene (mdpe) and its nanocomposites are investigated. for this purpose mdpe reinforced with different weight percentages of nano-sized calcium (2, 5, 10) are produced by compression moulding method. tensile tests have been carried out at different temperatures, i.e. 30, 60, 90c using thermomechanical analysis (tm...

in this research, the influence of adding micro- and nano- sized calcium carbonate powders to nylon-66 was investigated. mechanical properties of micro and nano- composites, including tensile strength, elongation, and young’s modulus, before and after ageing, were determined and analyzed. for this purpose, micro- and nano-sized caco3 particles were used as fillers to prepare micro-composites (c...

In this research, the influence of adding micro- and nano- sized calcium carbonate powders to nylon-66 was investigated. Mechanical properties of micro and nano- composites, including tensile strength, elongation, and Young’s modulus, before and after ageing, were determined and analyzed. For this purpose, micro- and nano-sized CaCO3 particles were used as fillers to prepare micro-composites (c...

The purpose of this study was to elucidate the characteristics and mechanisms of adsorption and desorption for heavy metals by micro and nano-sized biogenic CaCO3 induced by Bacillus subtilis, and the pH effect on adsorption was investigated. The results showed that the adsorption characteristics of Cd2+ and Pb2+ are well described by the Langmuir adsorption isothermal equation, and the maximum...

The parental material of soils in the Qilian Mountains of northwest China is mainly aeolian loess containing CaCO3 which may remain in soils under the semiarid-arid climate. To disclose the CaCO3 characteristics change with the altitude and the terrain attributes, we surveyed 18 soil profiles in an altitude sequence from 3076 m to 4510 m in the Hulugou Watershed in the Qilian Mountains, measure...

Rising atmospheric carbon dioxide (CO2) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed the saturation state of the oceans with respect to calcium carbonate (CaCO3) particles. Here we estimate the in situ CaCO3 dissolution rates for the global oceans from total alkalinity and chlorofluorocarbon data, and we also dis...

Core-shell structured CaCO3 microspheres (MSs) were prepared by a facile, one-pot method at room temperature. The adsorbent dosage and adsorption time of the obtained CaCO3 MSs were investigated. The results suggest that these CaCO3 MSs can rapidly and efficiently remove 99-100% of anionic dyes within the first 2 min. The obtained CaCO3 MSs have a high Brunauer-Emmett-Teller surface area (211.7...

Negatively Biased Flotation Column (NBFC) is a tool, which developed for the flotation of coarse-sized ores. Unlike conventional column, in this there no froth zone and wash-water usually not used. Therefore, hydrodynamically entrainment fine-sized particles into concentrate possible, may result decrease grade or yield concentrate.
 In study, operating parameters that can affect were inves...

Forty-seven patients with mild hypertension and 48 normotensive patients entered a blinded, parallel study in which they received a placebo, 10 mmol/day calcium carbonate (CaCO3), or 20 mmol/day CaCO3. There were no significant differences in blood pressure changes among the groups. In the hypertensive group and in patients with the highest blood pressure there were individual falls in systolic...