Über das rheologische Verhalten von Buchenholz verschiedener Feuchtigkeit bei Druckbeanspruchung längs der Faser / Considerations on the rheological behaviour of red beech wood of different moisture content when loaded by compression parallel to the grain / Au sujet du comportement rheologique du bois de hätre a divers etats d’humidite lors d’effort de compression axiale

1962 ◽  
Vol 4 (9) ◽  
pp. 313-319
Author(s):  
F. Kollmann
Keyword(s):  
Moisture Content ◽  
Beech Wood ◽  
Rheological Behaviour ◽  
Du Bois

The Effects of Amyloglucosidase, Glucose Oxidase and Hemicellulase Utilization on the Rheological Behaviour of Dough and Quality Characteristics of Bread

2017 ◽  
Vol 13 (2) ◽  
Author(s):  
Burak Altınel ◽  
S. Sezgin Ünal
Keyword(s):  
Moisture Content ◽  
Glucose Oxidase ◽  
Wheat Flour ◽  
Specific Volume ◽  
Rheological Behaviour ◽  
Quality Characteristics ◽  
Final Moisture Content ◽  
Whole Wheat ◽  
Flour Blends ◽  
Flour Blend

Abstract Wheat flour, whole wheat flour, 25 and 50 % rye flour substituted wheat flour blends, 15 and 30 % wheat bran substituted wheat flour blends were supplemented with amyloglucosidase (at 0.000875 and 0.001 %), glucose oxidase (at 0.0003 and 0.001 %) and hemicellulase (at 0.001 and 0.005 %). The effects of enzymes on the extensographic properties of dough and quality characteristics of bread (specific volume, baking loss percentage and final moisture content) were studied. The interaction between type of flour/blend, type of enzyme and dosage of enzyme affected resistance to extension, extensibility and ratio of resistance to extensibility of doughs significantly. The interactions between type of flour/blend, type of enzyme and dosage of enzyme affected specific volume, baking loss percentage and final moisture content of breads significantly. The findings in this study indicated that enzymes can exhibit unexpected effects on dough and bread properties depending on type of flour and dosage of enzyme.

Rheological Properties of Chestnuts Processed by Osmotic Dehydration and Convective Drying

2007 ◽  
Vol 13 (5) ◽  
pp. 369-374 ◽  
Author(s):  
F. Chenlo ◽  
R. Moreira ◽  
M.D. Torres
Keyword(s):  
Moisture Content ◽  
Rheological Properties ◽  
Osmotic Dehydration ◽  
Operation Time ◽  
Rheological Behaviour ◽  
Castanea Sativa ◽  
Convective Drying ◽  
Sucrose Content ◽  
Sucrose Solutions ◽  
Drying Rates

The effect of osmotic dehydration using sucrose solutions followed by a convective drying on the rheological properties of chestnuts (Castanea sativa M.) has been studied. Prisms of chestnuts (10 × 10 × 15mm) were immersed into sucrose solutions (60% w/w) at different times (1, 2, 8 and 24 h) at 25°C. The samples were dried with hot air at 65°C and 30 % of relative humidity during different times (0, 0.5, 1.5, 3 and 6 h). Finally, the rheological behaviour of chestnuts at different moisture and sucrose content was determined using a universal machine of mechanical tests. Osmotic dehydration kinetics was evaluated determining sucrose and moisture content. Sugar gain and water loss amounts increased with operation time. Drying kinetics analysis showed higher drying rates during first times. Rheological data (stress, strain and modulus of elasticity) changed strongly with water and sucrose content. At high moisture content samples with more sucrose content showed more ductile properties than no pre-treated osmotically samples and at low moisture content the presence of sugar led to harder samples.

scholarly journals Calibration of Electrical Resistance to Moisture Content for Beech Laminated Veneer Lumber “BauBuche S” and “BauBuche Q”

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 635
Author(s):  
Philippe Grönquist ◽  
Gianna Weibel ◽  
Claude Leyder ◽  
Andrea Frangi
Keyword(s):  
Moisture Content ◽  
Electrical Resistance ◽  
High Performance ◽  
Beech Wood ◽  
Gravimetric Method ◽  
Model Parameters ◽  
Data Set ◽  
Laminated Veneer Lumber ◽  
Calibration Models ◽  
Different Depths

Electrical resistance measurements are often employed for the purpose of nondestructive long-term monitoring of wood moisture content (MC) in timber structures. As a structural material for high-performance load-bearing applications in such structures, beech laminated veneer lumber (LVL) enjoys a growing popularity. However, due to the processing of beech LVL affecting physical properties, calibration curves for bulk beech wood cannot be used. In this study, resistance was measured on 160 beech LVL samples equilibrated in four different relative humidity (RH) climates. The results show a difference not only between the beech LVL products “BauBuche S” and “BauBuche Q”, but also between measurements at two different depths. For each data set, parameters for calibration models using two and using three model parameters were determined by regression analysis to MC determined by the gravimetric method.

scholarly journals Effects of Moisture Content and Grain Direction on the Elastic Properties of Beech Wood Based on Experiment and Finite Element Method

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 610
Author(s):  
Wei-Lian Fu ◽  
Hui-Yuan Guan ◽  
Sawata Kei
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Moisture Content ◽  
Elastic Properties ◽  
Elastic Constants ◽  
Beech Wood ◽  
Wood Products ◽  
Moisture Contents ◽  
Wide Range ◽  
Element Method

Beech wood (Fagus sylvatica L.) is used in a wide range of wood products. However, the influence of the wood’s moisture content on its mechanical functions will affect its structural strength. It would be complicated and time-consuming to experimentally measure wood’s mechanical functions under different moisture contents. Therefore, it is necessary to establish a prediction formula between the moisture content and elastic constants, and then verify whether its mechanical functions within a wide range of moisture content can be studied by using FEM (finite element method). In this study, which was based on experimentation, we studied the influence of a wide range of moisture contents and grain direction on the compressive yield strength, modulus of elasticity and shear modulus of beech wood. The relationship between the moisture content and elastic constants was established; the moisture sensitivities of different elastic parameters were obtained. Ultimately, compression curves under different moisture contents were plotted out, using both FEM and experimentation. According to the results, the interaction of moisture with the grain direction had a significant effect on the elastic constants of wood, with grain direction having a greater effect on the elastic properties than the moisture content. Moreover, the decay function can be used to fit these experimental results well. The elastic constants of beech wood responded differently to the moisture content, depending on whether it was in the longitude or transverse directions. Finally, this study proved the feasibility of using FEM to simulate wood’s compressive performance with a wide range of moisture contents.

scholarly journals Hygroscopicity of Longitudinally Compressed Wood

2017 ◽  
Vol 13 (2) ◽  
pp. 135-144 ◽  
Author(s):  
Mátyás Báder ◽  
Róbert Németh
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Beech Wood ◽  
Research Work ◽  
Modification Method ◽  
Vapour Adsorption ◽  
Long Time ◽  
The Difference ◽  
Compressed Wood ◽  
Control Samples

AbstractKnowledge of hygroscopicity is extremely important both in the use of native wood and modified wood. In this study, the modification method was steaming at 100 °C, then longitudinal compression at a rate of 20%. The moisture content (MC) of treated and untreated green beech wood (Fagus sylvaticaL.) was reduced in a climate chamber with gradual reduction of air humidity at 20 °C. The difference of calculated fibre saturation points between control samples and samples compressed for a long time was 6% (MC%). In the course of desorption, this difference decreased, and finally disappeared at 10% moisture content (40% relative humidity). In the second step of the research work, the speed of vapour adsorption was checked. The absolute dry samples were placed in air with 95% relative humidity. The highest deviation in the moisture content was 1% (MC%) between the control and the compressed samples. The compressed wood dries faster than the control samples under the same conditions. Furthermore, during adsorption, the moisture content of the compressed samples at room conditions is lower.

scholarly journals Influence of Moisture Content on the Strength of Finger Joints Bonded Beech Wood

2021 ◽  
pp. 0270-0274
Author(s):  
Alen Ibrisevic ◽  
Murco Obucina ◽  
Seid Hajdarevic ◽  
Goran Mihulja
Keyword(s):  
Moisture Content ◽  
Beech Wood ◽  
Finger Joints

scholarly journals Effects of water pretreatment on properties of pellets made from beech particles

2021 ◽  
Vol 75 (1) ◽  
pp. 39-51
Author(s):  
Jasmina Popovic ◽  
Mladjan Popovic ◽  
Milanka Djiporovic-Momcilovic ◽  
Ana Prahin ◽  
Vladimir Dodevski ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Moisture Content ◽  
Beech Wood ◽  
Ash Content ◽  
Hot Water ◽  
Specific Density ◽  
Heating Value ◽  
Water Pretreatment ◽  
Pretreatment Effects ◽  
Hot Water Pretreatment

Particles of beech wood were treated with hot water at the temperature of 150 oC, during 60 min, prior to the pelleting process. The applied hot water pretreatment affected the chemical composition and heating value of particles. Two groups of pellets, designated as PT 10 and PT 20, were produced from treated beech particles, with the moisture content of particles being 10.5 and 20.5 %, respectively. Pellets from nontreated beech particles (PNT) served as controls to assess the hot water pretreatment effects on the pellet properties. Both, the applied pretreatment, and the particle moisture content, affected properties of the obtained pellets. The heating value of PT 10 ad PT 20 pellets has increased for ~6 and 1 %, respectively. The mineral (ash) content in treated pellets decreased for about 24 % in comparison to that in PNT pellets. In addition, the bulk (apparent) density of pellets has increased for 21 % (PT 10) and 10 % (PT 20), as a consequence of the hot water pretreatment of particles. The specific density of PT 10 pellets was for 16 % higher, while the equilibrium moisture content (after conditioning at RH 68 % and 20.1?C) was for about 32 % lower in comparison to the respective properties of PNT pellets.

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