Effects Of Heat Treatment Methods Research Articles

The Effect of Heat Treatment Methods on the Structural Characteristics of Basalt Glass

The Effect of Heat Treatment Methods on the Structural Characteristics of Basalt Glass

Effects of heat-treatment methods on cytocompatibility and mechanical properties of dental products 3D-printed using photopolymerized resin.

The purpose of this study was to test heat-treatment methods for improving the cytocompatibility of dental 3D printable photopolymer resins. Nextdent C&B resin and a digital light processing 3D printer were used to print all specimens, which were divided into seven groups as follows: 1-month storage at controlled room temperature, 20 to 25 °C (RT), 24-hour storage at RT, 24-hour storage in RT water, 1-min immersion in 80 °C water, 1-min immersion in 100 °C water, 5-min immersion in 100 °C water, and autoclaving. Cell viability tests, cytotoxicity tests, and confocal laser scanning microscopy were performed to analyze the cytocompatibility of the 3D-printed resin. Fourier-transform infrared spectroscopy was performed after heat-treatment to determine the degree of conversion (DC). Immersing printed resin samples in 100 °C water for 1 or 5 min after the curing process was an effective method for increasing cytocompatibility by inducing the preleaching of toxic substances such as unpolymerized monomers, photoinitiators, and additives. Moreover, the DC can be increased by additional polymerization without affecting the mechanical properties of the material. Immersing the printed photosensitive dental resins in 100 °C water for 5 min is a suitable method for increasing cytocompatibility and the DC.

Printing adaptability and vitrification of UV photo-responsive silica nanocomposites

A 3D-printing-compatible approach is reported to construct special-shaped silica glass components. Printable silica-polymer slurries are optimized to obtain the shear-thinning colloidal suspensions with high solid loading and tunable rheological properties. The effects of heat treatment methods and solid loadings on the vitrification of printed parts are explored. To reveal the printing adaptability, the micro kinetic mechanism of free radical photopolymerization is introduced into the thickness-time equation to confirm the printing parameters. Taking into account the requirements of 3D printing for the slurry rheology and the linear shrinkage, a series of customizable silica glasses are constructed based on the parameters predicted by the model. Surprisingly, silica glasses show exceptionally smooth surfaces with a roughness of about 4 nm. The preceding observations confirm the obvious competitiveness of 3D printing relative to traditional glass forming methods, as well as the additional benefits of the freedom to design and produce complex geometries.

Effect of heat treatment on mechanical property of amorphous carbon films by magnetron sputtering

To investigate the effects of heat treatment methods and processes on the mechanical properties of amorphous carbon (a-C) films prepared using magnetron sputtering, the microstructures and mechanical properties of a-C films were characterized using X-ray photoelectron spectroscopy, nanoindentation testing, and ball disk friction testing. Results show that heat treatment helps to improve the mechanical properties of a-C films. The mechanical properties of a-C films are affected not only by the hybrid of SP2 and SP3 in the microstructure but also by their surface morphologies and the form of interface bonding between amorphous carbon films and silicon substrates after heat treatment. The hardness of the a-C films increased by 35.15 % upon treatment at the optimal temperature of 900 °C. The heat treatment also increased the Young's modulus of the films. Moreover, the heat treatment improved the wear resistance of the treated films with an optimal temperature of 1000 °C. The wear area is also reduced by 28 % compared with that before heat treatment. At 1200 °C, the wear resistance of a-C film decreased owing to the reduction in the SP2 carbon hybrid structure, and the wear mechanism of a-C films after heat treatment changed from mixed damage (abrasive and adhesive wears combined) to simple abrasive damage. All these results indicated the proposed magnetron sputtering heat treatment is an effective way to improve mechanical properties of a-C films. At the same time, the heat treatment also improved the interfacial adhesion between the amorphous carbon film and silicon wafer. Moreover, the interfacial adhesion between the amorphous carbon film and silicon wafer reached grade 5 when the heat treatment temperature exceeded 1000 °C.

EFFECT OF HEAT PROCESSING TREATMENTS ON THE CHEMICAL COMPOSITION AND FUNCTIONAL PROPERTIES OF LIMA BEAN (Phaseolus lunatus) FLOUR

Purpose: The effect of heat treatment methods on the nutrient composition and functional properties of lima bean (Phaseolus lunatus) flour were investigated.Methodology: The lima bean seeds were sorted, cleaned and processed into boiled, roasted and autoclaved lima bean flours. The flours obtained were analyzed for proximate composition, mineral content and functional properties using standard methods.Results: The proximate composition of the samples revealed that the flours had a range of moisture, 8.25±0.01 - 10.21±0.06%, crude protein, and 18.24 ±0.02 - 22.72±0.00%, ash, 3.94±0.13 - 4.82±0.02%, fat, 1.47±0.03 - 1.68±0.00%, crude fiber, 3.62±0.00 - 4.27±0.02%, carbohydrate, 57.31±0.13 - 62.89±0.01%, and energy 334.11±0.30 - 339.91±0.18kJ/100g, respectively. The mineral composition showed that the flours contained 176.89±0.002 - 234.72±0.17mg/100g calcium, 2.38±0.03 - 3.24±0.00mg/100g iron, 68.36±0.00 - 73.62±0.26mg/100g sodium, 163.73±0.11 - 195.33±0.01mg/100g magnesium, and 125.86±0.00 - 136.76±0.06mg/100g potassium, and 158.78±0.03 - 184.29±0.01mg/100g phosphorus, respectively. The result of the functional properties of the flours equally revealed that the water absorption, solubility index, foam capacity, oil absorption and swelling capacities and bulk density of the samples were significantly (p<0.05) increased by roasting than the boiling and autoclaving treatments. However, the nutrient composition and the functional properties of the flours observed suggested that the processed flours have the potentials to be used as nutritional supplements and functional ingredients in the preparation of a wide range of food products than the raw sample.

A comparative study of the effect of different cooking methods on the quality and shucking of mussels

Fresh mussels (Mytilus galloprovincialis) were heat-treated for various time intervals, using moist-heat and dry-heat processes such as boiling, steaming, baking, and microwaving. The effect of heat treatment methods on cooking loss and shucking (shell opening) of mussels was investigated. All heat treatment methods succeeded 100% shell opening. Results indicated that cooking loss and shell opening of the heat-treated mussels significantly increased with increasing process time. The cooking loss was for the majority of the heat-treated mussels higher than 20% while greater cooking loss values were recorded for the steam-treated mussels. Microwave heating scored better results in shell opening of the mussels compared to the other methods. Multiple response optimization of process parameters revealed that the microwave treatment was found to be the optimal for improving the quality (cooking loss) and the efficiency of shell opening of mussels. The color of the heat-treated mussel meat was more or less orange. Practical applications Nowadays, the food industry faces the challenge to explore new methodologies in order to improve the quality characteristics of their products and, thereby, gain the consumers acceptability. During mussel heat processing, cooking loss is a very important factor strongly related to the heat treatment methods and affects the quality and yield of the final product. Although heating may lead to significant cooking losses, it is required in order to facilitate the shucking of mussels. To address this matter, in this study, the effect of different heat treatment methods on cooking loss and shell opening of mussels are investigated. The results suggest that the microwave heat treatment method can potentially be implemented in industrial mussel processing, guarantying better quality end products than the other methods do.

Effect of Heat Treatment Methods on the Fatigue Behaviour of Hammermill: A Review

The production of reliable and sustainable hammermill involves heat treatment which is part of overall cost of production. Heat treatment has engrossed a lot of interests since it is one of the main production methods to improve corrosion resistance of coatings, enhancing malleability, hardness and strength to lessen mechanical or chemical damage. Nevertheless, various heat treatment procedures had resulted to hammermill failure as a result of material wear, erosive wear, impact wear, machine clogging and shock loading wear which eventually affects the efficiency of the hammermill. The study thus engrossed on some particular thermal treatment on mild steels and their impacts on hammermill applications. Progressive loss of material (wear) is a common failure that leads to hammermill fatigue due to cyclic stress posed on the hammers based on literature reviews. The mode of quenching and especially the discrepancy in the concentration affects the efficiency of the crushing unit. The fatigue performance of materials is being enhanced due to stress-relief heat treatment which makes it possible to increase the strength and ductility of the samples. However, the utilization of experimental model and simulation approach for stress prediction for the study is further recommended.

Studies on the properties of RO membranes for salt and boron removal: Influence of thermal treatment methods and rinsing treatments

The physicochemical properties and performance of thin film composite (TFC) membranes depend on its synthesis conditions. In this study, TFC membranes were fabricated using interfacial polymerization (IP) method and the effects of heat treatment methods and post-IP rinsing (prior to heat curing step) on the membrane performances were investigated. Keeping the substrate in minimal heat exposure could prevent substrate pore annealing that potentially reduces the membrane water permeability. Evidently, the membranes with only polyamide (PA) layer being heat-treated exhibited >250% enhancement in pure water flux (PWF) compared to the membranes where both PA and substrate layer were heat-treated. Also, the membranes rinsed with pure n-hexane tended to display higher PWF without significantly decreasing solute rejection, possibly due to the reduced membrane cross-linking following the removal of unreacted monomers and excess solvent from the membrane surface. The membrane performance became practically the same after post-IP rinsing, regardless of the solvent used in the IP reaction, suggesting that the disparity in the membrane performance is mainly caused by the difference in solvent evaporation rate during heat treatment. The variations in solvent surface tension and viscosity during the IP reaction meanwhile did not play a key role affecting PA layer chemistry and performance.