Flake Drying Temperature Affects Mat Properties during Pressing

Holzforschung ◽  
2002 ◽  
Vol 56 (5) ◽  
pp. 558-562 ◽  
Author(s):  
C. J. Martino ◽  
S. Shrauti ◽  
S. Banerjee ◽  
L. P. Otwell ◽  
E. W. Price
Keyword(s):  
Contact Angle ◽  
High Temperature ◽  
Surface Hydrophobicity ◽  
Environmental Benefits ◽  
General Shape ◽  
Drying Temperature ◽  
The Core ◽  
Pore Closure ◽  
Lower Temperature ◽  
High Temperature Drying

Summary The contact angle of water on wood rises sharply as the wood approaches dryness. The general shape of the rise can be reproduced through thermodynamic calculations that consider the presence of extractives on the surface. SEM work confirms that extractives move progressively to the surface with increasing drying temperature. Other factors such as pore closure also contribute to surface hydrophobicity. The temperature profile within a stack of flakes during accelerated pressing shows a break at 100°C when flakes dried at high temperature are processed. Moisture is known to be driven from the outer layers of the stack to the core during early pressing. If the flake surface is hydrophobic then this moisture would film on the surface rather than penetrate into the flake. Subsequent evaporation of the moisture would lead to high pressure. Hence, flakes dried at high temperature should be more prone to delamination. High-temperature drying also promotes VOC emissions and there should be operational and environmental benefits to drying at lower temperature.

scholarly journals STUDY ON CONCENTRATIONS OF ACIDS AND ALCOHOLS EMITTED BY PINUS RADIATA DURING HIGH-TEMPERATURE DRYING

Wood Research ◽  
2021 ◽  
Vol 66 (3) ◽  
pp. 427-436
Author(s):  
Jiangyi Chu ◽  
Jinghui Jiang ◽  
Chusheng Qi ◽  
Yongdong Zhou
Keyword(s):  
Acetic Acid ◽  
High Temperature ◽  
Relative Humidity ◽  
Moisture Content ◽  
Formic Acid ◽  
Pinus Radiata ◽  
Wood Moisture ◽  
Drying Temperature ◽  
Kiln Temperature ◽  
High Temperature Drying

The purpose of this paper is to investigate the influence of kiln temperature, relative humidity and wood moisture content on the content of acid and alcohol released in the drying process of high temperature kiln by studying the radiated pine sawn timber of 40mm thickness. The drying temperature was between 101°C and 115°C, the relative humidity in the drying kiln was reduced from 86.1% to 39.6%, the moisture content of the lumber was reduced from 106.16% to 11.98%, and gas extraction was executed nine times with an extraction speed of 1.0 L•min-1 and a sampling time of 30 min. The concentrations of acids and alcohols were analyzed by HPLC. The results showed that the concentrations of formic acid, acetic acid, and methanol emitted in the kiln during drying were 215.6-748.2, 4148.8-16803.2, and 6381.9-15648.9 mg•m-3, respectively, and these concentrations were significantly higher than the relevant standards. The concentrations of the emitted formic acid and acetic acid were proportional to the drying temperature, the concentrations of the emitted formic acid and acetic acid were inversely proportional to the relative humidity in the kiln and the moisture content of the lumber. The concentration of the emitted methanol was independent of the drying temperature, relative humidity in the kiln, and moisture content of the lumber. It is therefore suggested that formic acid, acetic acid, and methanol be separately recovered during the high-temperature drying of Pinus radiata lumber.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Comparative studies of nitrogen plasma and argon plasma treatment on the strength of PBO fibre reinforced high-temperature resistant thermoplastic composite

2021 ◽  
pp. 095400832098729
Author(s):  
K Sudheendra ◽  
Jennifer Vinodhini ◽  
M Govindaraju ◽  
Shantanu Bhowmik
Keyword(s):  
Contact Angle ◽  
High Temperature ◽  
Plasma Treatment ◽  
Sessile Drop ◽  
Dynamic Contact Angle ◽  
Argon Plasma ◽  
Film Surface ◽  
Fibre Surface ◽  
Nitrogen Plasma ◽  
Thermoplastic Composite

The study involves the processing of a novel poly [1, 4-phenylene-cis-benzobisoxazole] (PBO) fibre reinforced high-temperature thermoplastic composite with polyaryletherketone (PAEK) as the matrix. The PBO fibre and the PAEK film surface was modified using the method of argon and nitrogen plasma treatment. The investigation primarily focuses on evaluating the tensile properties of the fabricated laminates and correlating it with the effect of plasma treatment, surface characteristics, and its fracture surface. A 5% decrease in tensile strength was observed post argon plasma treatment while a 27% increase in strength was observed post nitrogen plasma treatment. The morphology of the failure surface was investigated by scanning electron microscopy and an interfacial failure was observed. Furthermore, the effect of plasma on the wettability of PBO fibres and PAEK film surface was confirmed by the Dynamic Contact Angle analysis and sessile drop method respectively. FTIR spectral analysis was done to investigate the effect of plasma treatment on the chemical structure on the surface. The results of the wettability study showed that the argon plasma treatment of the fibre surface increased its hydrophobicity while nitrogen plasma treatment resulted in the reduction of contact angle.

scholarly journals Performance Evaluation of Asphalt Rubber Mixture with Additives

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1200 ◽  
Author(s):  
Cheng ◽  
Liu ◽  
Ren ◽  
Huang
Keyword(s):  
High Temperature ◽  
Fatigue Cracking ◽  
Crumb Rubber ◽  
Good Choice ◽  
Environmental Benefits ◽  
Fatigue Properties ◽  
Control Group ◽  
Rubber Mixture ◽  
Asphalt Rubber ◽  
Temperature Performance

Crumb rubber, as a recycled material used in asphalt mixture, has gained more attention in recent years due to environmental benefits and the advantages of its pavement, such as excellent resistance to cracking, improved durability, less road maintenance, lower road noise, etc. However, the high-temperature performance of mixture with crumb rubber does not perform well. In order to improve the performance, this paper examined the effect of additives on the laboratory performance of asphalt rubber Stone Matrix Asphalt (AR-SMA) with additives. Three groups of AR-SMA: no additives, Styrene–Butadiene–Styrene (SBS) and Granular Polymer Durable additive (GPDa) were included, with no additives as a control group. Each group was investigated at three asphalt rubber content (ARC): 6.4%, 6.9%, 7.4% with regard to high-temperature and fatigue properties. The results show that with increasing ARC, the high-temperature performance of mixture without additive decreases, and the high-temperature performance increases first and then decreases for SBS and GPDa. Moreover, the rutting resistance of AR-SMA with GPDa at 6.9% ARC performs best. Under the condition of mixtures with appropriate ARC, AR-SMA with GPDa has higher fatigue life and sensitivity to fatigue cracking than the control group. Simultaneously, the fatigue performance of AR-SMA with GPDa is not as significant as that without additive with increasing ARC. In a word, GPDa is a good choice to improve the performance of AR-SMA. However, it should be noted that optimal asphalt content of AR-SMA mixtures with GPDa is higher than that of traditional mixtures.

High temperature drying characteristics of crushed rice for animal feed

2014 ◽  
Vol 7 (3) ◽  
pp. 133-138 ◽  
Author(s):  
Fumina Tanaka ◽  
Kotaro Yamashita ◽  
Ai Tanaka ◽  
Fumihiko Tanaka ◽  
Daisuke Hamanaka ◽  
...  
Keyword(s):  
High Temperature ◽  
Animal Feed ◽  
Drying Characteristics ◽  
High Temperature Drying

Comparison of Two Protein Extraction Methods for Tea Residues

2011 ◽  
Vol 138-139 ◽  
pp. 933-936 ◽  
Author(s):  
Xuan Chen ◽  
Hong Yu Luo ◽  
Jun Yu ◽  
Peng Xiang Yue ◽  
Lin Zhou ◽  
...  
Keyword(s):  
High Temperature ◽  
Protein Extraction ◽  
Ethanol Concentration ◽  
Extraction Methods ◽  
Extraction Yield ◽  
Factorial Experiments ◽  
Extraction Technology ◽  
Digestion Method ◽  
Solid Ratio ◽  
Lower Temperature

Alcohol-alkali method and base digestion method were investigated to extract proteins from tea residues, respectively. According to single factorial experiments, results showed that the optimal extraction technology of alcohol-alkali method were pH 12, temperature of 80 °C, ethanol concentration of 60%, liquid-solid ratio of 40, 60 min, and the protein extraction rate reached 15.0%. And the optimal extract conditions of base digestion were pH 12, temperature of 80 °C, liquid-solid ratio of 50, 80 min, which made the protein yield reached 31.5%. Furthermore, alcohol-alkali method was more beneficial to protein extraction from tea residues under lower temperature and weak alkali condition (40-60 °C, pH 8-10). While base digestion had higher extraction yield under high temperature and strong alkali condition (60-80 °C, pH 11-12).

Nano-Goethite (α-FeOOH) Magnetic Structure Investigated Using Ising Core-Shell Model: Preliminary Study

2021 ◽  
Vol 1028 ◽  
pp. 193-198
Author(s):  
Budi Adiperdana ◽  
Nadya Larasati Kartika ◽  
Risdiana
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Shell Model ◽  
Magnetic Structure ◽  
Paramagnetic State ◽  
Core Shell ◽  
The Core ◽  
Preliminary Study

Ising core-shell model was proposed to reconstruct superparamagnetism hysteresis in nano-goethite (α-FeOOH). Core and shell set as antiferromagnetic and paramagnetic state respectively. Core and shell radius varies until the theoretical hysteresis fit with experiment hysteresis. At low temperature, the hysteresis reconstructed nicely with 55% antiferromagnetic core contribution and 45% paramagnetic shell contribution. At high temperature, the core-shell model show unrealistic result compared to the pure paramagnetic state.

Mineral partitioning in milk and milk permeates at high temperature

2011 ◽  
Vol 79 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Divina D Kaombe ◽  
Yanhong Du ◽  
Michael J Lewis
Keyword(s):  
High Temperature ◽  
Calcium Phosphate ◽  
Temperature Dependence ◽  
Casein Micelle ◽  
Soluble Phase ◽  
Ionic Calcium ◽  
Separation Temperature ◽  
Two Temperatures ◽  
Lower Temperature ◽  
Mineral Partitioning

The soluble phase of milk was separated at 20 and 80°C using ultrafiltration. The resulting permeates were then subjected to further ultrafiltration and dialysis at close to these two temperatures. It was found that pH, Ca2+ and soluble Ca decreased as the separation temperature increased both in original UF permeates and in dialysates obtained from these permeates, but P decreased only slightly. The major reason for these changes was due to the precipitation of calcium phosphate/citrate complexes onto the casein micelle with concomitant release of H+. The pH of both permeates and dialysates from milk at 20°C were slightly higher than for milk. When UF permeates collected at 20 and 80°C, were each dialysed at both these temperatures, the dialysate collected at 80°C showed much less temperature dependence for pH and ionic calcium compared with that collected at 20°C. This is in contrast to milk, which shows considerable temperature dependence for pH and ionic calcium. Further experiments revealed that the pH and Ca2+ concentration of permeates showed high temperature dependence above the temperature at which they were separated, but a much lower temperature dependence below that temperature. These findings suggest that dialysis and UF of milk at high temperature provide the best means yet for estimating the pH and ionic calcium of milk at that temperature.

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