Study on the Formation Mechanism of the Pyrolysis Products of Lignite at Different Temperatures Based on ReaxFF-MD

In this paper, the process of the transformation from kaolin to metakaolin was investigated. The kaolin was calcined at different temperatures and analyzed by Xray diffraction (XRD), Fourier transform infrared spectra (FTIR) and solid state nuclear magnetic resonance (NMR). The formation of metakaolin structure was based on the stacking polyhedrons changes, which originated from dehydroxylation of kaolinite. With increasing temperature, kaolin kept structure of kaolinite unchanged in the course of dehydroxylation and then structure of kaolinite transformed to metakaolin when the dehydroxylation was over. It was demonstrated that the essence of pozzolanic activity of metakaolin. The result revealed that the pozzolanic activity of metakaolin increased with increasing temperature at the range of 600~900 °C.

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Formation Mechanism of Gehlenite-Anorthite Materials Containing ZrO2 from Andalusite, CaCO3 and ZrO2

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.788.120 ◽

2018 ◽

Vol 788 ◽

pp. 120-125

Author(s):

Edyta Śnieżek ◽

Maciej Ludwig ◽

Jacek Szczerba

Keyword(s):

Phase Composition ◽

Chemical Analysis ◽

Formation Mechanism ◽

Weight Ratio ◽

Phase System ◽

Different Temperatures ◽

Calcium Aluminosilicates

This paper reports the results of using natural andalusite (Al2SiO5) in combination with CaCO3 and ZrO2 in order to obtain aluminosilicate product. This work was devoted to the study of the mechanism of new phases creation in the Al2SiO5-CaO-ZrO2 phase system during heating at different temperatures (1000, 1100, 1200, 1300 and 1400°C). Al2SiO5, CaCO3, and ZrO2 were used in a weight ratio of 45:50:5, respectively. According to the phase composition and chemical analysis in microareas, it was found, that andalusite reacted with CaO giving two calcium aluminosilicates: gehlenite and anorthite at 1400°C. ZrO2 was presented as the separated phase at this temperature. Other occurring transition phases were: CaZrO3 at 1000 and 1200°C, Ca2SiO4 at 1000, 1100 and 1200°C, Ca3ZrSi2O9 at 1300°C. The synthesis mostly depended on the diffusion of Ca2+ ions.

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The Effective Thermal Conductivity of Porous Polymethacrylimide Foams

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.609-610.196 ◽

2014 ◽

Vol 609-610 ◽

pp. 196-200 ◽

Cited By ~ 1

Author(s):

Peng Yue ◽

Lin Qiu ◽

Xing Hua Zheng ◽

Da Wei Tang

Keyword(s):

Experimental Data ◽

Thermal Conductivity ◽

Effective Thermal Conductivity ◽

Formation Mechanism ◽

3Ω Method ◽

Temperature Range ◽

Different Temperatures ◽

The Relationship

A freestanding sensor-based 3ω method was employed to measure the effective thermal conductivity of porous polymethacrylimide (PMI) foams with different densities at different temperatures. Experimental data showed that within the measuring temperature range, the effective thermal conductivity increased with temperature. Moreover, the formation mechanism of the relationship between the effective thermal conductivity and temperature was analyzed in this paper.

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TG-FTIR Study on the Heat Treatment of Plasticized Melt-Spun PAN Precursors for Carbon Fiber

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.193-194.444 ◽

2012 ◽

Vol 193-194 ◽

pp. 444-447

Author(s):

Bin Yan ◽

Ke Qing Han ◽

Jing Jie Zhang ◽

Dan Wang ◽

Su Ping Liu ◽

...

Keyword(s):

Heat Treatment ◽

Carbon Fiber ◽

Formation Mechanism ◽

Pyrolysis Products ◽

Ftir Study ◽

Melt Spun ◽

Main Decomposition ◽

Decomposition Stages ◽

Pan Fibers

In this paper, the evolution of the gas evolved during the heat treatment of the plasticized melt-spun PAN fibers was investigated by TG-FTIR. TG, DTG and G-S (Gram-Schmidt) curves showed that there were two main decomposition stages during the heat treatment of melt-spun PAN fibers. And the results indicated that the main pyrolysis products were NH3 (966 cm-1 and 932 cm-1), HCN (713 cm-1), H2O (3650 cm-1), CH4 (1305cm-1), CO (2180 cm-1), CO2 (2360 cm-1 and 667 cm-1). The release of NH3 and HCN started at the same temperature 220 °C, which were the main products during the stabilization step. Besides, the formation mechanism of the pyrolysis products is presented in detail.

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Abuse of Smoking Methamphetamine Mixed with Tobacco: II. The Formation Mechanism of Pyrolysis Products

Journal of Forensic Sciences ◽

10.1520/jfs12864j ◽

1990 ◽

Vol 35 (3) ◽

pp. 12864J ◽

Cited By ~ 14

Author(s):

Hitoshi Sekine ◽

Yuju Nakahara

Keyword(s):

Formation Mechanism ◽

Pyrolysis Products

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The formation mechanism of hollow spherulites and molecular conformation of curcumin and solvate

CrystEngComm ◽

10.1039/d0ce01230k ◽

2020 ◽

Vol 22 (48) ◽

pp. 8405-8411

Author(s):

Xuxing Wan ◽

Songgu Wu ◽

Yan Wang ◽

Junbo Gong

Keyword(s):

Formation Mechanism ◽

Molecular Conformation ◽

Different Temperatures ◽

Molecular Ratios

In this study, curcumin 1,4-dioxane solvates (CUR–DIO) were obtained in two molecular ratios of 1 : 1.5 (CUR–DIO-1.5) and 1 : 1 (CUR–DIO-1) at different temperatures.

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Formation mechanism of micro-flows in aqueous poly(ethylene oxide) droplets on a substrate at different temperatures

Petroleum Science ◽

10.1007/s12182-013-0275-4 ◽

2013 ◽

Vol 10 (2) ◽

pp. 262-268

Author(s):

Yin-Chun Hu ◽

Qiong Zhou ◽

Yu-Feng Wang ◽

Yun-Yang Song ◽

Li-Shan Cui

Keyword(s):

Ethylene Oxide ◽

Formation Mechanism ◽

Micro Flows ◽

Different Temperatures ◽

Poly Ethylene Oxide ◽

Poly Ethylene

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Insights on the Formation Mechanism of Ultra-Low Friction of Phenolic Resin Graphite at High Temperature

Coatings ◽

10.3390/coatings12010006 ◽

2021 ◽

Vol 12 (1) ◽

pp. 6

Author(s):

Fan Zhang ◽

Peng Yin ◽

Qunfeng Zeng ◽

Jianmei Wang

Keyword(s):

High Temperature ◽

Formation Mechanism ◽

Tribological Properties ◽

Phenolic Resin ◽

Ambient Air ◽

Low Friction ◽

Ni Alloy ◽

Different Temperatures ◽

Important Basis ◽

Insight Into

In the present paper, the influences of high temperature on the tribological properties of phenolic resin graphite (PRG) sliding against tungsten carbide-nickel (WC-Ni) alloy in ambient air were investigated systematically. Results demonstrated that the antifriction behaviors of PRG was sensitive to high temperature and PRG exhibits ultra-low coefficient of friction (CoF) of about 0.01–0.015. The low CoF is attributed to the formation of graphite tribofilms, which shows different formation processes on the contact interface at different temperatures (room temperature, 200, 300 and 400 °C). These findings provide insight into the formation mechanism of graphite tribofilms, and provide an important basis for improving the tribological properties of graphite-based friction materials and manufacturing new graphite for seal applications.

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