Chemical and Mechanical Characterization of Thermally Modified Gmelina arborea Wood

Gmelina arborea (Roxb. ex. Sm.) wood samples were thermally modified at 180 °C, 200 °C and 220 °C for 3 h, by employing a process similar to ThermoWood®. The resulting effects on the basic chemical composition and mechanical properties were determined. The results were analyzed statistically with ANOVA, and Least Square Deviation was used to compare means. Generally, after the thermal modification (TM) process, the cellulose, hemicelluloses and extractives content decreased significantly. By contrast, lignin proportions increased significantly. Untreated wood and samples modified at 180 °C indicated comparable modulus of elasticity (MOE), modulus of rupture (MOR), degree of integrity (I), fine fraction (F) and resistance to impact milling (RIM). Noteworthy reductions however occurred at 200 °C and 220 °C. Significant increases in Brinell hardness (BH) took place at 180 °C, recording a high decrease at 220 °C. Gmelina arborea could be modified suitably at 180 °C for structural and other purposes. To take advantage of other improved properties, modification at 200 °C could be employed for non-structural uses.

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Fire-resistance, physical, and mechanical characterization of binderless rice straw particleboards

BioResources ◽

10.15376/biores.12.4.8539-8549 ◽

2017 ◽

Vol 12 (4) ◽

pp. 8539-8549 ◽

Cited By ~ 2

Author(s):

Cristina C. Ferrandez-Garcia ◽

Teresa Garcia-Ortuño ◽

Maria T. Ferrandez-Garcia ◽

Manuel Ferrandez-Villena ◽

Clara E. Ferrandez-Garcia

Keyword(s):

Thermal Conductivity ◽

Rice Straw ◽

Mechanical Characterization ◽

Physical And Mechanical Properties ◽

Modulus Of Rupture ◽

Particle Sizes ◽

Thickness Swelling ◽

European Standards ◽

Internal Bonding Strength

Binderless rice straw particleboards were successfully manufactured by hot pressing at low temperatures (110 °C) while under pressure (2.6 MPa) using a three-step process. Two particle sizes were used: 0.25 to 1.00 mm and 0.00 to 0.25 mm. Three pressing times (15 min, 30 min, and 60 min) were studied. Eighteen types of boards were made. The physical and mechanical properties were assessed in accordance with the European Standards for wood-based particleboards, namely density, thickness swelling, water absorption, thermal conductivity, modulus of rupture, modulus of elasticity, internal bonding strength, and reaction to fire. Two panels exceeded the requirements for general uses. The panels had a low thermal conductivity (0.076 W/mK to 0.091 W/mK). The panels were classified in the same class as the fire retardants (class Bd0, according to EN ISO 11925-2:2002).

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Mechanical characterization of polyester resin composite with natural fibers

Journal of Scientific and Technical Applications ◽

10.35429/jsta.2021.20.7.17.23 ◽

2021 ◽

pp. 17-23

Author(s):

Carmen SALAZAR-HERNÁNDEZ ◽

Juan Manuel MENDOZA-MIRANDA ◽

Alfredo CORTES-LÓPEZ ◽

Luis Fernando GONZÁLEZ-MÉNDEZ

Keyword(s):

Polyester Resin ◽

Mechanical Characterization ◽

Brinell Hardness ◽

Resin Composite ◽

Natural Fibers ◽

New Materials ◽

Impact Simulation ◽

The Matrix ◽

The Impact

In this paper, composite materials reinforced with natural fibers were studied, such as: Jute (MC-RY) and Manta (MC-RM) as a proposal for new materials for the manufacture of a prototype for automotive defense. The materials were manufactured as laminates and characterized mechanically through stress, bending, impact and Brinell hardness index tests. The results indicated that both reinforcers improved the mechanical strength of the matrix by up to 71%, as well as the impact energy absorption by 14%. The mechanical properties for MC-RY determined in flexure (bending = 56 MPa, Eflection = 4.16 GPa and maximum = 14 mm) were used to perform an impact simulation in two different models created in SolidWork, the results indicated that the MC-RY could be used for the construction of the defense using 3 layers of this material.

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Mechanical characterization of Trebisacce stone: preliminary results

Rendiconti online della Società Geologica Italiana ◽

10.3301/rol.2016.14 ◽

2016 ◽

Vol 38 ◽

pp. 47-50

Author(s):

Giulia Forestieri ◽

Maurizio Ponte

Keyword(s):

Mechanical Characterization ◽

Preliminary Results

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Massively Parallel Mechanical Characterization of Nanowires

10.26226/morressier.5f5f8e69aa777f8ba5bd5f86 ◽

2020 ◽

Author(s):

Rodrigo Bernal

Keyword(s):

Mechanical Characterization ◽

Massively Parallel

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Spectro-mechanical Characterization of Aromaticity and Maturity of Kerogens in Oil Shale at 6 nm Spatial Resolution

10.26434/chemrxiv.7336160 ◽

2018 ◽

Author(s):

Devon Jakob ◽

Le Wang ◽

Haomin Wang ◽

Xiaoji Xu

Keyword(s):

Spatial Resolution ◽

Oil Shale ◽

Infrared Imaging ◽

Mechanical Characterization ◽

Optical Diffraction ◽

Chemical Compositions ◽

Valuable Insight ◽

Eagle Ford Shale

<p>In situ measurements of the chemical compositions and mechanical properties of kerogen help understand the formation, transformation, and utilization of organic matter in the oil shale at the nanoscale. However, the optical diffraction limit prevents attainment of nanoscale resolution using conventional spectroscopy and microscopy. Here, we utilize peak force infrared (PFIR) microscopy for multimodal characterization of kerogen in oil shale. The PFIR provides correlative infrared imaging, mechanical mapping, and broadband infrared spectroscopy capability with 6 nm spatial resolution. We observed nanoscale heterogeneity in the chemical composition, aromaticity, and maturity of the kerogens from oil shales from Eagle Ford shale play in Texas. The kerogen aromaticity positively correlates with the local mechanical moduli of the surrounding inorganic matrix, manifesting the Le Chatelier’s principle. In situ spectro-mechanical characterization of oil shale will yield valuable insight for geochemical and geomechanical modeling on the origin and transformation of kerogen in the oil shale.</p>

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