Chemical changes accompanying oxygenation of coal by air and deoxygenation of oxidized coal by thermal treatment

Fuel ◽  
1989 ◽  
Vol 68 (9) ◽  
pp. 1129-1133 ◽  
Author(s):  
Ashim K. Banerjee ◽  
Debapriya Choudhury ◽  
Samar S. Choudhury
Keyword(s):  
Thermal Treatment ◽  
Chemical Changes ◽  
Oxidized Coal

scholarly journals Physico-Chemical Investigation of Endodontic Sealers Exposed to Simulated Intracanal Heat Application: Hydraulic Calcium Silicate-Based Sealers

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 728
Author(s):  
David Donnermeyer ◽  
Magdalena Ibing ◽  
Sebastian Bürklein ◽  
Iris Weber ◽  
Maximilian P. Reitze ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Thermal Treatment ◽  
Film Thickness ◽  
Physical Properties ◽  
Calcium Silicate ◽  
Setting Time ◽  
Chemical Properties ◽  
Chemical Changes ◽  
Time Flow ◽  
Heat Application

The aim of this study was to gain information about the effect of thermal treatment of calcium silicate-based sealers. BioRoot RCS (BR), Total Fill BC Sealer (TFBC), and Total Fill BC Sealer HiFlow (TFHF) were exposed to thermal treatment at 37 °C, 47 °C, 57 °C, 67 °C, 77 °C, 87 °C and 97 °C for 30 s. Heat treatment at 97 °C was performed for 60 and 180 s to simulate inappropriate application of warm obturation techniques. Thereafter, specimens were cooled to 37 °C and physical properties (setting time/flow/film thickness according to ISO 6876) were evaluated. Chemical properties (Fourier-transform infrared spectroscopy) were assessed after incubation of the specimens in an incubator at 37 °C and 100% humidity for 8 weeks. Statistical analysis of physical properties was performed using the Kruskal-Wallis-Test (P = 0.05). The setting time, flow, and film thickness of TFBC and TFHF were not relevantly influenced by thermal treatment. Setting time of BR decreased slightly when temperature of heat application increased from 37 °C to 77 °C (P < 0.05). Further heat treatment of BR above 77 °C led to an immediate setting. FT-IR spectroscopy did not reveal any chemical changes for either sealers. Thermal treatment did not lead to any substantial chemical changes at all temperature levels, while physical properties of BR were compromised by heating. TFBC and TFHF can be considered suitable for warm obturation techniques.

Chemical changes in extra virgin olive oils from Slovenian Istra after thermal treatment

2008 ◽  
Vol 108 (2) ◽  
pp. 446-454 ◽  
Author(s):  
Erika Bešter ◽  
Bojan Butinar ◽  
Milena Bučar-Miklavčič ◽  
Terezija Golob
Keyword(s):  
Thermal Treatment ◽  
Chemical Changes ◽  
Virgin Olive Oils ◽  
Olive Oils

scholarly journals Chemical Changes in Extra Virgin Argan Oil after Thermal Treatment

2013 ◽  
Vol 8 (1) ◽  
pp. 1934578X1300800
Author(s):  
Saïd Gharby ◽  
Hicham Harhar ◽  
Badr Eddine Kartah ◽  
Dom Guillaume ◽  
Zoubida Charrouf
Keyword(s):  
High Temperature ◽  
Thermal Treatment ◽  
Physicochemical Parameters ◽  
Edible Oils ◽  
Polar Compounds ◽  
Chemical Changes ◽  
Argan Oil

Physicochemical parameters, measured every 6 hours, of extra virgin argan oil heated for 24 h at 180°C were investigated and compared with those of five other edible oils treated in the same thermoxidative condition. Argan oil was found to be particularly stable at high temperature, its level of polar compounds remaining low even after 24 h of heating.

Molecular interaction of fibrinogen with thermally modified titanium dioxide nanoparticles

RSC Advances ◽  
2014 ◽  
Vol 4 (76) ◽  
pp. 40428-40434 ◽  
Author(s):  
A. S. Zhao ◽  
S. Zhou ◽  
Y. Wang ◽  
J. Chen ◽  
C. R. Ye ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Thermal Treatment ◽  
Platelet Activation ◽  
Molecular Interaction ◽  
Titanium Dioxide Nanoparticles ◽  
Surface Chemical ◽  
Chemical Changes

Novelty lies in the attempt to connect protein changes and subsequent platelet activation to surface/chemical changes upon thermal treatment of TiO2NP's.

Chemical changes in polyvinylacetate under radiation-thermal treatment

1967 ◽  
Vol 9 (6) ◽  
pp. 1359-1366
Author(s):  
V.A. Larin ◽  
Z.A. Markova ◽  
V.I. Yakovenko ◽  
N.A. Bakh
Keyword(s):  
Thermal Treatment ◽  
Chemical Changes

Chemical Changes to Woody Polymers Due to High-Temperature Thermal Treatment Assessed with near Infrared Spectroscopy

2016 ◽  
Vol 24 (6) ◽  
pp. 555-562 ◽  
Author(s):  
Jakub Sandak ◽  
Anna Sandak ◽  
Ottaviano Allegretti
Keyword(s):  
Infrared Spectroscopy ◽  
Thermal Treatment ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Treatment Temperature ◽  
Absorption Bands ◽  
Chemical Changes ◽  
Novel Method ◽  
Treatment Procedures ◽  
Original Approach

Near infrared spectroscopy and an original approach for visualisation of spectra are proposed here for characterisation of vacuum thermally modified samples of eight wood species representing softwoods and hardwoods. Significant changes in absorption bands were observed in conjunction with an increase of treatment temperature. A novel method for visualisation of the degradation patterns (xylograms) is capable of highlighting peculiarities in chemical changes to woody polymers due to the thermal treatment. This method also allows observation of kinetics and permits comparison of thermal stability of investigated species. Such knowledge might be helpful for further optimisation of thermal treatment procedures at an industrial scale. Furthermore, xylograms as a simple and illustrative method might be suitable for visualisation of other modification processes of wood as well as of other materials.

Pollutant Identification by Selected Area Electron Diffraction

1974 ◽  
Vol 32 ◽  
pp. 532-533
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson ◽  
C. W. Walker
Keyword(s):  
Thermal Treatment ◽  
Electron Diffraction ◽  
Sample Preparation ◽  
Crystal Structures ◽  
Water Samples ◽  
Environmental Samples ◽  
Short Review ◽  
Selected Area Electron Diffraction ◽  
Multiple Component

Selected area electron diffraction (SAD) has been used successfully to determine crystal structures, identify traces of minerals in rocks, and characterize the phases formed during thermal treatment of micron-sized particles. There is an increased interest in the method because it has the potential capability of identifying micron-sized pollutants in air and water samples. This paper is a short review of the theory behind SAD and a discussion of the sample preparation employed for the analysis of multiple component environmental samples.

Development of Crystallinity in Turbostratic Boron Nitride Derived from Polymeric Precursors

1991 ◽  
Vol 49 ◽  
pp. 954-955
Author(s):  
X. Qiu ◽  
A. K. Datye ◽  
T. T. Borek ◽  
R. T. Paine
Keyword(s):  
Thermal Treatment ◽  
Boron Nitride ◽  
Diffraction Pattern ◽  
Polymeric Precursors ◽  
Polymer Precursors ◽  
Diffuse Ring

Boron nitride derived from polymer precursors is of great interest for applications such as fibers, coatings and novel forms such as aerogels. The BN is prepared by the polymerization of functionalized borazine and thermal treatment in nitrogen at 1200°C. The BN powders obtained by this route are invariably trubostratic wherein the sheets of hexagonal BN are randomly oriented to yield the so-called turbostratic modification. Fib 1a and 1b show images of BN powder with the corresponding diffraction pattern in fig. 1c. The (0002) reflection from BN is seen as a diffuse ring with occational spots that come from crystals of BN such as those shown in fig. 1b. The (0002) lattice fringes of BN seen in these powders are the most characteristic indication of the crystallinity of the BN.

Sign in / Sign up

Export Citation Format

Share Document