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

CrystEngComm ◽  
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.

Formation Mechanism and its Pozzolanic Activity of Metakaolin

2014 ◽  
Vol 602-603 ◽  
pp. 620-623 ◽  
Author(s):  
Mei Rong Wang ◽  
Ning Guo ◽  
Pei Gang He ◽  
Jing Bo Yu ◽  
De Chang Jia
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Fourier Transform ◽  
Solid State ◽  
Magnetic Resonance ◽  
Formation Mechanism ◽  
Infrared Spectra ◽  
Fourier Transform Infrared ◽  
Pozzolanic Activity ◽  
Different Temperatures ◽  
Increasing Temperature

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.

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

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.

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

ACS Omega ◽  
2021 ◽  
Author(s):  
Xin He ◽  
Hongqing Zhu ◽  
Yujia Huo ◽  
Wei Wang
Keyword(s):  
Formation Mechanism ◽  
Pyrolysis Products ◽  
Different Temperatures

α,ω-Dihexylsexithiophene Self-Assembled Nanostructures on Mica: Atomic Force Microscopy Study

2012 ◽  
Vol 18 (4) ◽  
pp. 844-851 ◽  
Author(s):  
Li Wang ◽  
Shuhong Ye ◽  
Huizhen Yuan ◽  
Yonghai Song ◽  
Haozhi Zhu ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Formation Mechanism ◽  
Molecular Conformation ◽  
Polar Solvent ◽  
Microscopy Study ◽  
Mica Surface ◽  
Atomic Force Microscopy Study ◽  
Force Microscopy ◽  
Atomic Force ◽  
Self Assembled

AbstractSelf-assembled nanostructures of α,ω-dihexylsexithiophene (DH6T) formed by spreading DH6T solutions onto freshly cleaved mica surface were studied by atomic force microscopy. The effects of solvent and concentration on the nanostructures of DH6T molecules were studied. Flat, well-ordered, and platelet-like domains were observed on mica surfaces after treatment with various polar solvent solutions of DH6T. These domains form a uniform film with height of 2.4 ± 0.2 nm, which is consistent with a 45° tilt in the molecular conformation of DH6T on mica surfaces. The formation mechanism of these multilayers is discussed in detail.

The Effective Thermal Conductivity of Porous Polymethacrylimide Foams

2014 ◽  
Vol 609-610 ◽  
pp. 196-200 ◽  
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.

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

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

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

Coatings ◽  
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.

Study on Phase Stability during Pressure-Less Sintering Process of Slag α-Sialon Powder and Properties of As-Sintered Materials

2013 ◽  
Vol 746 ◽  
pp. 97-100 ◽  
Author(s):  
He Zhang ◽  
Yao Deng ◽  
Ying Zhang ◽  
Jiu Xin Jiang
Keyword(s):  
High Temperature ◽  
Formation Mechanism ◽  
Phase Stability ◽  
Sintering Process ◽  
Temperature Synthesis ◽  
High Temperature Synthesis ◽  
Unit Cells ◽  
Different Temperatures ◽  
Sialon Powder ◽  
Sintered Materials

The pressure-less sintering of slag α-Sialon powder, derived from slag wastes by self-propagating high-temperature synthesis technology, was carried out and the phase assemblages of slag α-Sialon sintered at different temperatures were studied. The results showed that the formation of β-Sialon phase did occur during the pressure-less sintering and was restrained to some extent via mass diffusion of Ca2+/Mg2+ added in embedded powder in samples. α-Sialon phase with two different unit cells was detected in samples sintered at 1700°C and above, and the formation mechanism was also discussed.

Sign in / Sign up

Export Citation Format

Share Document