Crystallite size and shape in Twaron fibers heat treated at different temperatures using WAXS

Sediments commonly contain organic material which appears as refractory carbonaceous material in metamorphosed sedimentary rocks. Grew and others have shown that relative carbon content, crystallite size, X-ray crystallinity and development of well-ordered graphite crystal structure of the carbonaceous material increases with increasing metamorphic grade. The graphitization process is irreversible and appears to be continous from the amorphous to the completely graphitized stage. The most dramatic chemical and crystallographic changes take place within the chlorite metamorphic zone.The detailed X-ray investigation of crystallite size and crystalline ordering is complex and can best be investigated by other means such as high resolution transmission electron microscopy (HRTEM). The natural graphitization series is similar to that for heat-treated commercial carbon blacks, which have been successfully studied by HRTEM (Ban and others).

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Heat Treatment Influence on the Corrosion Resistance of a Cu-Al-Fe-Mn Bronze

Revista de Chimie ◽

10.37358/rc.18.5.6260 ◽

2018 ◽

Vol 69 (5) ◽

pp. 1055-1059 ◽

Cited By ~ 1

Author(s):

Mariana Ciurdas ◽

Ioana Arina Gherghescu ◽

Sorin Ciuca ◽

Alina Daniela Necsulescu ◽

Cosmin Cotrut ◽

...

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Structural Changes ◽

Heating Temperature ◽

Galvanic Corrosion ◽

Cooling Water ◽

Open Circuit ◽

Water Quenching ◽

Heat Treated ◽

Different Temperatures

Aluminium bronzes are exhibiting good corrosion resistance in saline environments combined with high mechanical properties. Their corrosion resistance is obviously confered by the alloy chemical composition, but it can also be improved by heat treatment structural changes. In the present paper, five Cu-Al-Fe-Mn bronze samples were subjected to annealing heat treatments with furnace cooling, water quenching and water quenching followed by tempering at three different temperatures: 200, 400 and 550�C. The heating temperature on annealing and quenching was 900�C. The structure of the heat treated samples was studied by optical and scanning electron microscopy. Subsequently, the five samples were submitted to corrosion tests. The best resistance to galvanic corrosion was showed by the quenched sample, but it can be said that all samples are characterized by close values of open-circuit potentials and corrosion potentials. Concerning the susceptibility to other types of corrosion (selective leaching, pitting, crevice corrosion), the best corrosion resistant structure consists of a solid solution, g2 and k compounds, corresponding to the quenched and 550�C tempered sample.

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Prediction of Thiol Group Changes in Minced Raw and Cooked Chicken Meat with Plant Extracts—Kinetic and Neural Network Approaches

Animals ◽

10.3390/ani11061647 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1647

Author(s):

Anna Kaczmarek ◽

Małgorzata Muzolf-Panek

Keyword(s):

Plant Extracts ◽

Predictive Models ◽

External Validation ◽

Thiol Group ◽

Chicken Meat ◽

Validation Dataset ◽

Heat Treated ◽

Different Temperatures ◽

Meat Samples ◽

Network Approaches

The aim of the study was to develop predictive models of thiol group (SH) level changes in minced raw and heat-treated chicken meat enriched with selected plant extracts (allspice, basil, bay leaf, black seed, cardamom, caraway, cloves, garlic, nutmeg, onion, oregano, rosemary, and thyme) during storage at different temperatures. Meat samples with extract addition were stored under various temperatures (4, 8, 12, 16, and 20 °C). SH changes were measured spectrophotometrically using Ellman’s reagent. Samples stored at 12 °C were used as the external validation dataset. SH content decreased with storage time and temperature. The dependence of SH changes on temperature was adequately modeled by the Arrhenius equation with average high R2 coefficients for raw meat (R2 = 0.951) and heat-treated meat (R2 = 0.968). Kinetic models and artificial neural networks (ANNs) were used to build the predictive models of thiol group decay during meat storage. The obtained results demonstrate that both kinetic Arrhenius (R2 = 0.853 and 0.872 for raw and cooked meat, respectively) and ANN (R2 = 0.803) models can predict thiol group changes in raw and cooked ground chicken meat during storage.

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Effect of Powder Heat Treatment on Chemical Composition and Thermoelectric Properties of Bismuth Antimony Telluride Alloys Fabricated by Combining Water Atomization and Spark Plasma Sintering

Materials ◽

10.3390/ma14112993 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2993

Author(s):

Dong-won Shin ◽

Peyala Dharmaiah ◽

Jun-Woo Song ◽

Soon-Jik Hong

Keyword(s):

Spark Plasma Sintering ◽

Thermoelectric Properties ◽

Hole Concentration ◽

Bismuth Antimony Telluride ◽

Plasma Sintering ◽

Heat Treated ◽

Water Atomization ◽

Powder Samples ◽

Different Temperatures ◽

Spark Plasma

In this work, Bi0.5Sb1.5Te3 materials were produced by an economically viable and time efficient water atomization process. The powder samples were heat treated at different temperatures (673 K, 723 K, 743 K, 773 K, 803 K, and 823 K) followed by spark plasma sintering (SPS). It was found that the Te evaporated slightly at 723 K and 743 K and became dominated at 773 K, 803 K, and 823 K, which severely influences the thermoelectric properties. The electrical conductivity was significantly improved for over 803 K heat treated samples due to the remarkable improvement in hole concentration. The power factor values for the 803 K and 823 K samples were significantly larger at T > 350 K compared to other samples. Consequently, the peak ZT of 0.92 at 350 K was obtained for the 803 K sample, which could be useful in commercial thermoelectric power generation.

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Elasto-plastic deformation of glass-like carbons heat-treated at different temperatures

Carbon ◽

10.1016/s0008-6223(00)00272-4 ◽

2001 ◽

Vol 39 (10) ◽

pp. 1525-1532 ◽

Cited By ~ 54

Author(s):

Norio Iwashita ◽

Michael V. Swain ◽

John S. Field ◽

Naoto Ohta ◽

Shingo Bitoh

Keyword(s):

Plastic Deformation ◽

Heat Treated ◽

Different Temperatures

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Effect of calcination temperature and calcination time on the kaolinite/tio2 composite for photocatalytic reduction of CO2

GeoScience Engineering ◽

10.2478/v10205-011-0022-2 ◽

2012 ◽

Vol 58 (4) ◽

pp. 10-22 ◽

Cited By ~ 10

Author(s):

Martin Reli ◽

Kamila Kočí ◽

Vlastimil Matějka ◽

Pavel Kovář ◽

Lucie Obalová

Keyword(s):

Crystallite Size ◽

Physical Adsorption ◽

Photocatalytic Reduction ◽

Thermal Hydrolysis ◽

Calcination Time ◽

Different Temperatures ◽

Higher Temperature ◽

Titanyl Sulphate ◽

Reduction Of Co2 ◽

Hydrolysis Of

Abstract The kaolinite/TiO2 composite (60 wt% of TiO2) was prepared by thermal hydrolysis of a raw kaolin suspension in titanyl sulphate and calcined at different temperatures (600, 650 and 700°C) and for different times (1, 2 and 3 h). The obtained samples were characterized by XRPD, N2 physical adsorption and SEM, and tested for photocatalytic reduction of CO2. The different calcination conditions did not influence TiO2 phase composition, only slightly changed the specific surface area, and significantly affected crystallite size of kaolinite/TiO2 composite. A higher temperature and longer duration of calcination lead to higher crystallinity of the powder. The photocatalytic results showed that the crystallite size determined the efficiency of kaolinite/TiO2 photocatalysts.

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Formation of Grain Structures of Thermal Sprayed Nickel Coatings and the Coating Properties

Materials Science Forum ◽

10.4028/www.scientific.net/msf.502.517 ◽

2005 ◽

Vol 502 ◽

pp. 517-0

Author(s):

Kenji Murakami

Keyword(s):

Steel Substrate ◽

Nickel Coatings ◽

Grain Structures ◽

Heat Treated ◽

Columnar Grains ◽

Different Temperatures ◽

Plasma Sprayed ◽

Equiaxed Grains ◽

Sprayed Coatings ◽

Lamellar Interfaces

Pure nickel powder was low pressure plasma sprayed onto a steel substrate held at different temperatures during spraying. The as-sprayed coatings consist of columnar grains whose axes are nearly perpendicular to the lamellae composing the coatings. As the coating temperature becomes higher, the length of the columnar grains increases and is longer than the thickness of the lamellae, indicating the growth of the grains across the lamellar interfaces during spraying. On the other hand, the coatings that were heat treated after spraying consist of coarse equiaxed grains. The coatings that experienced high temperatures during spraying or the heat treated coatings have large porosity and contain large globular pores. The hardness, apparent density and the tensile strength of the coating itself were the highest for the coating prepared at a low temperature and became low on heat treatment. The thermal conductivity in the direction perpendicular to the coating was the largest for the coating that consisted of long columnar grains.

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Preparation and Microwave Permittivity of Nano-Sized Si/C/N Powder

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3571 ◽

2005 ◽

Vol 475-479 ◽

pp. 3571-3574 ◽

Cited By ~ 5

Author(s):

Xiao Kui Liu ◽

Wan Cheng Zhou ◽

Fa Luo ◽

Dong Mei Zhu

Keyword(s):

Nitrogen Content ◽

Vapor Deposition ◽

Chemical Vapor ◽

Dissipation Factor ◽

Nano Powder ◽

Heat Treated ◽

Different Temperatures ◽

Degree Of Crystallization ◽

Microwave Permittivity ◽

N Powder

Nano-sized Si/C/N powders are prepared from hexamethyldisilazane ((CH3)3Si)2NH) by chemical vapor deposition (CVD) at different pyrolysis temperatures from 900°C to 1200°C. The as-formed Si/C/N nano powder is amorphous, and after controlled heat-treatment, SiC crystals formed. The composition of the Si/C/N powders prepared at different conditions is analyzed and the result shows that the nitrogen content of the Si/C/N powder is related to the synthesizing temperature. Si/C/N powders heat-treated at different temperatures are mixed with paraffin wax and the microwave permittivity of the mixture is measured. The result shows that the e¢, e², and the dissipation factor tg d ( e²/ e¢) of the mixture are high at the frequency of 8.2~12.4GHz, and the nitrogen content and the degree of crystallization have influence on the microwave permittivity. We believe that the high value of e¢, e² ,and tg d are due to the dielectric relaxation as the result of nitrogen atoms doped in silicon carbide lattice.

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Influence of different method and different storage life on moisture and senzorial evaluation of durable salamis

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200856040183 ◽

2008 ◽

Vol 56 (4) ◽

pp. 183-196

Author(s):

Hana Šulcerová ◽

Jiří Štencl ◽

A. Šulcová

Keyword(s):

Storage Time ◽

Storage Temperature ◽

Heat Treated ◽

Different Temperatures ◽

The Difference ◽

Total Difference ◽

Cut Surface ◽

Sausage Casing ◽

General Appearance

Heat-treated salamis “Vysočina“ were produced with standard way in a meat factory; their diameter was 55 mm. Samples were stored under laboratory conditions at different temperatures: 5, 10, 15, 20, and 25 °C and sensory analysed every week during one month storage. The dry matter (d.m.) was measured, too. Descriptors of general appearance, sausage casing, texture, cut surface, dry edge, smell, taste, and salty were monitored. Biggest changes were in descriptors general appearance and sausage casing (P < 0.001) and also in dry edge (P < 0.010) during the month period. Germs of moulds were found only at 5 and 10 °C. Rapid increase of d.m. in samples was noticeable in the first week of the storage time. It was 3 % d.m. at 5 °C and 11 % d.m. at 25 °C. Increase of d.m. of salamis continues slowly in the next three weeks period; the total difference was about 10 % d.m. in the temperature range measured. Decrease of d.m. at 5 °C was noticed in the last week of the measurement. The difference was 3.5 % d.m. This change means that the equilibrium moisture content of the samples of salamis has been reached at the temperature 5 °C. The best sensorial quality of salamis “Vysočina” was in the storage temperature ranged from 15 to 20 °C.

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Torrefaction of Almond and Walnut Byproducts

Frontiers in Energy Research ◽

10.3389/fenrg.2021.643306 ◽

2021 ◽

Vol 9 ◽

Author(s):

Zach McCaffrey ◽

Lennard Torres ◽

Bor-Sen Chiou ◽

Saulo Rocha Ferreira ◽

Luiz Eduardo Silva ◽

...

Keyword(s):

Physicochemical Properties ◽

Moisture Absorption ◽

Calorific Value ◽

Dynamic Vapor Sorption ◽

Energy Applications ◽

Thermochemical Process ◽

Heat Treated ◽

The Us ◽

Torrefied Biomass ◽

Different Temperatures

While the US nut industry is growing, markets for nut by-products, particularly nutshells and tree prunings, have not kept pace. Torrefaction is a thermochemical process used to improve physicochemical properties of biomass for energy and other applications. The goal of the paper was to characterize the effects of a range of torrefaction conditions on the properties of nut by-product feedstock. The process consists of thermal treatment of biomass at a temperature between 200 and 300°C in the absence of oxygen, where final material properties of the torrefied biomass depend on the temperature, heating rate, and residence time. In general, torrefied biomass exhibits higher hydrophobicity and calorific value with reduced moisture absorption compared to untreated biomass, making it an ideal fuel source for energy applications compared to raw biomass. In this study, almond shells of soft, semi-soft, and hardshell varieties, as well as walnut shells and almond wood, were torrefied at two different temperatures (230 and 290°C) and three different residence times (20, 40, and 60 min) in order to characterize the physicochemical properties. The thermal behavior of raw and heat-treated biomass was investigated by TGA analysis, elemental analysis, pH, helium pycnometry, FTIR spectroscopy, and dynamic vapor sorption analysis.

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