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Determination Of Form (Shape) Stability Performance On Curved Laminated Wood (Lvl) Elements

The following determines performance stability of curved laminated wood elements made with a vacuum membrane press. For this purpose, 13 layers of 1.5 mm thick beech (Fagus orientalis Lipsky), sessile oak (Quercus petrean Liebl) and pine (Pinus sylvestris) veneer layers were glued with D4 adhesive using a vacuum membrane press and curved laminated wood samples were prepared. Diagonal compression test was applied on the prepared samples. The highest diagonal compression strength difference found between beech laminate and oak laminate was statistically insignificant. Most low strength samples consisted of laminated pine.

Anahtar Kelimeler:

Vacuum Membrane Presses, Laminated Wood

Investigation of Dependence of Electronic Structure, Spectroscopic Features, and Interionic Weak Interactions on Alkyl Chain Length in [CnC1im][NTF2] (n=1,2, .. 8) Ionic Liquids

In this work, electronic structure and some physical and optical properties [CnC1im][NTf2][1-alkyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide] (n = 1, 2, ... 8) were investigated theoretically via density functional theory calculations within the dependency of alkyl chain length. Geometrical structure and frequency calculations along with population analysis were performed at DFT-B3LYP/6- 311G(d,p) level of theory. Inter- and intra-molecular hydrogen bonding and van der Waals interactions were visualized by using reduced density gradient analysis. Geometrical structure and vibrational features were analyzed in detail for the strong interaction regions, and their relation to nano structural organization was explored. Characteristics of interionic interactions were fingerprinted on the basis of Becke surface and Hirshfeld analysis. Electronic transition properties were investigated by time dependent density functional theory. The reason for colored appearance comes with elongation of chain length is explained through absorbance spectra.

Keywords:

Ionic liquid, DFT, TDDFT Weak Interaction analysis, Nano structural organization,

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