scholarly journals Suberin Fatty Acid Hydrolysates from Outer Birch Bark for Hydrophobic Coating on Aspen Wood Surface

2021 ◽  
Author(s):  
Anuj Kumar ◽  
Risto Korpinen ◽  
Veikko Möttönen ◽  
Erkki Verkasalo
Keyword(s):  
Fatty Acid ◽  
Wood Surface ◽  
Birch Bark ◽  
Aspen Wood ◽  
Hydrophobic Coating

Surface properties and structure of aspen wood.

2016 ◽  
Author(s):  
И.В. Коваленко ◽  
М.А. Чубинский ◽  
Д.С. Русаков ◽  
Г.С. Варанкина
Keyword(s):  
Surface Properties ◽  
Wood Surface ◽  
Fractal Theory ◽  
Aspen Wood ◽  
Surface Finishes ◽  
Surface Irregularities ◽  
Corrosion Susceptibility ◽  
Adhesive Molecules ◽  
First Time ◽  
Flow Study

Применение древесины осины в промышленном производстве материалов и изделий ограничено из-за ее низких механических свойств, подверженности поражению коррозионно-деструктивной гнили, отсутствием должного обоснования технологии ее переработки. Невостребованная осина осложняет условия хозяйствования в лесу, ухудшает породный состав древостоев, препятствует восстановлению хвойных пород древесины. Древесина осины хуже смачивается водой по сравнению с другими породами. Изучение ее поверхностных свойств и строения на микроуровне представляет безусловный интерес для изучения взаимодействия древесины с водой, жидкими клеящими и защитно-декоративными веществами. Это сложная многопараметрическая задача, решение которой может явиться новым инструментом для обоснования наукоемких технологических процессов сушки, пропитки, склеивания и облагораживания древесины. Истинная поверхность древесины, образованная в результате обработки резанием (лущением, пилением, фрезерованием) значительно больше ее проекции на плоскости в результате разрезания микроструктурных элементов. Неровности на поверхности искажают результаты измерения поверхностных свойств, определяемых на основе угла смачивания. Учитывая то, что размеры стенок клеток меньше размеров полостей, истинная площадь поверхности древесины, в зависимости от вида разреза, может в десятки раз превышать кажущуюся. Ухудшение способности смачиваться объясняет образование на поверхности капель клея, нанесенного на шпон методом вальцевания. При горячем прессовании фанеры в первый момент времени повышается подвижность молекул клея, снижается упругость древесины, поверхность выравнивается, улучшая условия адгезионного взаимодействия связующего и древесины. Для определения истинных характеристик древесины, обоснования расхода клея, способности древесины поглощать жидкость необходимо знать размеры ее микроструктурных элементов и характер их распределения, объем поверхностных полостей. Эффективный радиус полостей древесины осины может быть описан с использованием теории фракталов. The use of aspen wood in manufacturing of materials and products is limited due to its low mechanical properties, corrosion susceptibility destructive lesion decay, its lack of proper justification processing technology. Unclaimed aspen difficult economic conditions in the forest, degrades the species composition of forest stands and prevents restoration of softwood. Wood aspen worse moistened with water compared to other breeds. The study of its structure and surface properties at the micro level is of great interest to study the interaction of wood with water, liquid adhesives and protective-decorative materials. This is the problem whose solution can be a new tool for the study of science-intensive technological processes of drying, impregnation, gluing and surface finishes. Real wood surface, formed by the machining (peeling, sawing, milling) significantly greater its projection on the plane as a result of cutting the microstructural elements. Surface irregularities distort the results of measurement of surface properties which are determined based on the contact angle. Given that the size of the cell walls is less than the size of the cavities, the true surface area of the veneer, depending on the type of incision, may be ten times the apparent. The deterioration of the ability of wetted explains the formation of droplets on the surface of adhesive deposited on the veneer by rolling. When plywood hot pressing at a first time increases mobility of adhesive molecules, decreases the modulus of elasticity of wood, surface is aligned, improving the conditions of interaction of the glue and the wood. To determine the true characteristics of the wood, glue flow study, the ability of wood to absorb liquid it is necessary to know the size of microstructural elements and their distribution, the amount of surface cavities. The effective radius of aspen wood cavities can be described using fractal theory.

Fast formation of hydrophobic coating on wood surface via an energy-saving dielectric barrier discharges plasma

2018 ◽  
Vol 125 ◽  
pp. 128-136 ◽  
Author(s):  
Weimin Chen ◽  
Xiaoyan Zhou ◽  
Xiaotao Zhang ◽  
Mohammad Feizbakhshan ◽  
Yizhong Cao ◽  
...  
Keyword(s):  
Energy Saving ◽  
Wood Surface ◽  
Dielectric Barrier Discharges ◽  
Dielectric Barrier ◽  
Hydrophobic Coating ◽  
Barrier Discharges

Enzymatic catalysis as a versatile tool for the synthesis of multifunctional, bio-based oligoester resins

2016 ◽  
Vol 18 (7) ◽  
pp. 1923-1929 ◽  
Author(s):  
Stefan Semlitsch ◽  
Susana Torron ◽  
Mats Johansson ◽  
Mats Martinelle
Keyword(s):  
Fatty Acid ◽  
Hydroxy Fatty Acid ◽  
Enzymatic Catalysis ◽  
Candida Antarctica ◽  
Birch Bark ◽  
Lipase B ◽  
Versatile Tool

Candida antarctica lipase B (CalB) was used as a chemoselective catalyst for the synthesis of multifunctional oligoester resins based on an epoxy-functional ω-hydroxy-fatty acid (EFA) extracted from birch bark.

Temperature Dependence of the Critical Electron Dose for Fatty Acid Monolayers

1982 ◽  
Vol 40 ◽  
pp. 78-79
Author(s):  
Kenneth H. Downing ◽  
Robert M. Glaeser
Keyword(s):  
Electron Beam ◽  
Fatty Acid ◽  
Inelastic Scattering ◽  
Temperature Dependence ◽  
Structural Damage ◽  
Direct Result ◽  
Second Step ◽  
Strong Temperature Dependence ◽  
Electron Dose ◽  
Covalent Bonds

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.

Effect of light intensity on the ultrastructure of the filamentous cyanobacterium, Anabaena variabilis

1988 ◽  
Vol 46 ◽  
pp. 300-301
Author(s):  
C. S. Bricker ◽  
S. R. Barnum ◽  
B. Huang ◽  
J. G. Jaworskl
Keyword(s):  
Fatty Acid ◽  
Light Intensity ◽  
Acid Content ◽  
Fatty Acid Content ◽  
Anabaena Variabilis ◽  
Chloroplast Envelope ◽  
Major Constituent ◽  
Filamentous Cyanobacterium ◽  
Photosynthetic Membrane ◽  
Effect Of Light

Cyanobacteria are Gram negative prokaryotes that are capable of oxygenic photosynthesis. Although there are many similarities between eukaryotes and cyanobacteria in electron transfer and phosphorylation during photosynthesis, there are two features of the photosynthetic apparatus in cyanobacteria which distinguishes them from plants. Cyanobacteria contain phycobiliproteins organized in phycobilisomes on the surface of photosynthetic membrane. Another difference is in the organization of the photosynthetic membranes. Instead of stacked thylakolds within a chloroplast envelope membrane, as seen In eukaryotes, IntracytopIasmlc membranes generally are arranged in three to six concentric layers. Environmental factors such as temperature, nutrition and light fluency can significantly affect the physiology and morphology of cells. The effect of light Intensity shifts on the ultrastructure of Internal membrane in Anabaena variabilis grown under controlled environmental conditions was examined. Since a major constituent of cyanobacterial thylakolds are lipids, the fatty acid content also was measured and correlated with uItrastructural changes. The regulation of fatty acid synthesis in cyanobacteria ultimately can be studied if the fatty acid content can be manipulated.

The effects of low-ratio n-6/n-3 PUFA on biomarkers of inflammation: a systematic review and meta-analysis

2021 ◽  
Author(s):  
Yali Wei ◽  
Yan Meng ◽  
Na Li ◽  
Qian Wang ◽  
Liyong Chen
Keyword(s):  
Systematic Review ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acid ◽  
Meta Analysis ◽  
Chain Polyunsaturated Fatty Acid ◽  
Inflammation Markers ◽  
Pufa Supplementation ◽  
Long Chain

The purpose of the systematic review and meta-analysis was to determine if low-ratio n-6/n-3 long-chain polyunsaturated fatty acid (PUFA) supplementation affects serum inflammation markers based on current studies.

Fatty acid ketodienes and fatty acid ketotrienes: Michael addition acceptors that accumulate in wounded and diseased Arabidopsis leaves

2000 ◽  
Vol 24 (4) ◽  
pp. 467-476 ◽  
Author(s):  
Sabine Vollenweider ◽  
Hans Weber ◽  
Stephanie Stolz ◽  
Aurore Chetelat ◽  
Edward E. Farmer
Keyword(s):  
Fatty Acid ◽  
Michael Addition
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