Impregnation of poplar wood (Populus euramericana) with methylolurea and sodium silicate sol and induction of in-situ gel polymerization by heating

Abstract Poplar wood (Populus euramericana cv. “I-214”) has been impregnated by pulse dipping at 0.7–0.8 MPa for 30 min with a mixture of methylolurea and sodium silicate, and the sol modifier has been cured within the wood micropores by in situ gel polymerization by kiln drying, so that a Si-O-Si framework was formed. The treated wood acquired higher mechanical strength and its hygroscopicity was lowered. It was demonstrated by X-ray diffraction that sodium silicate crystallized within the interfibrillar region of the cell wall. Fourier transform infrared spectra showed that reactions occurred between the wood-OH, Si-OH, and N-CH2-OH from methylolurea to form C-O-Si and C-O-C bonds. As visible by scanning electron microscopy (SEM), the Si-O-Si framework was embedded in the pretreated wood. Moreover, SEM-energy-dispersive X-ray spectroscopy analysis revealed that the modifier formed layers from various thicknesses ranging from a thin layer on the cell walls up to big amounts filling the lumen.

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A Superhydrophobic, Antibacterial, and Durable Surface of Poplar Wood

Nanomaterials ◽

10.3390/nano11081885 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1885

Author(s):

Xinyu Wu ◽

Feng Yang ◽

Jian Gan ◽

Zhangqian Kong ◽

Yan Wu

Keyword(s):

Stearic Acid ◽

Antibacterial Properties ◽

Alkali Resistance ◽

Poplar Wood ◽

X Ray Diffraction ◽

X Ray ◽

Different Temperatures ◽

Acid And Alkali Resistance ◽

The Stability

The silver particles were grown in situ on the surface of wood by the silver mirror method and modified with stearic acid to acquire a surface with superhydrophobic and antibacterial properties. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray energy spectroscopy (XPS) were used to analyze the reaction mechanism of the modification process. Scanning electron microscopy (SEM) and contact angle tests were used to characterize the wettability and surface morphology. A coating with a micro rough structure was successfully constructed by the modification of stearic acid, which imparted superhydrophobicity and antibacterial activity to poplar wood. The stability tests were performed to discuss the stability of its hydrophobic performance. The results showed that it has good mechanical properties, acid and alkali resistance, and UV stability. The durability tests demonstrated that the coating has the function of water resistance and fouling resistance and can maintain the stability of its hydrophobic properties under different temperatures of heat treatment.

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Copper precipitation of Cu-monoethanolamine preservative in wood

Holzforschung ◽

10.1515/hf-2012-0014 ◽

2012 ◽

Vol 66 (8) ◽

pp. 1017-1024 ◽

Cited By ~ 2

Author(s):

Myung Jae Lee ◽

Paul Cooper

Keyword(s):

Diffraction Analysis ◽

Treated Wood ◽

X Ray Diffraction ◽

Fixation Rate ◽

X Ray ◽

Copper Precipitation ◽

Effects Of Ph ◽

Ph Decrease

Abstract Copper precipitation is one of the important Cu fixation mechanisms of Cu-amine-treated wood. In the present work, possible pathways of Cu precipitation have been investigated via in vitro and in situ studies focusing on effects of pH and temperature and Cu species formed in Cu-monoethanolamine (Cu-Mea)-treated wood. Higher-concentration Cu-Mea solutions required a lower pH and higher amounts of acid for the precipitation because of the higher amount of free Mea in the preservative-wood system. For this reason, Cu fixation during wet conditioning of wood treated to high Cu retention (2.0% treating solution) resulted in only a slight pH decrease and low Cu fixation. When lower-concentration solutions (0.67% and 0.2%) were applied, the pH decreased enough for Cu precipitation, and the much higher Cu fixation rate was driven by both chemisorption and precipitation. Evaluation of leaching after wet conditioning and drying showed that additional Cu precipitation could occur during drying. Wet conditioning of Cu-Mea-treated wood at 50°C showed outwardly faster and higher Cu fixation, but resulted in higher Cu leaching. According to X-ray diffraction analysis, the in vitro precipitated Cu was a mixture of azurite and malachite, and possibly, Cu2O formed as a result of Cu-Mea decomposition.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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In-situ investigation by X-ray diffraction and wafer curvature of phase formation and stress evolution during metal thin film – silicon reactions

Zeitschrift für Kristallographie Supplements ◽

10.1524/zksu.2007.2007.suppl_26.81 ◽

2007 ◽

Vol 2007 (suppl_26) ◽

pp. 81-89

Author(s):

O. Thomas

Keyword(s):

Thin Film ◽

Phase Formation ◽

Stress Evolution ◽

X Ray Diffraction ◽

X Ray ◽

Wafer Curvature ◽

Thin Film Silicon ◽

Metal Thin Film ◽

In Situ Investigation

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Leaching Studies of Cement-Glass Package Containing Sodium Borate

MRS Proceedings ◽

10.1557/proc-84-393 ◽

1986 ◽

Vol 84 ◽

Cited By ~ 3

Author(s):

Masahiro Okamoto ◽

Koichi Chino ◽

Tsutomu Baba ◽

Tatsuo Izumida ◽

Fumio Kawamura ◽

...

Keyword(s):

Sodium Silicate ◽

Liquid Waste ◽

Sodium Borate ◽

Pressurized Water Reactor ◽

X Ray Diffraction ◽

Adsorption Ability ◽

Pressurized Water ◽

X Ray ◽

Solidification Reaction ◽

Main Components

AbstractA new solidification technique using cement-glass, which is a mixture of sodium silicate, cement, additives, and initiator of the solidification reaction, was developed for sodium borate liquid waste generated from pressurized water reactor (PWR) plants. The cement-glass could solidify eight times as much sodium borate as cement could, because the solidifying reaction of the cement-glass is not hindered by borate ions.The reaction mechanism of sodium silicate and phosphoric silicate (initiator), the main components of cement-glass, was studied through X-ray diffraction and compressive strength measurements. It was found that three- dimensionally bonded silicon dioxide was produced by polymerization of the two silicates. The leaching ratio of cesium from the cement-glass package was one-tenth that of the cement one. This low value was attributed to a high cesium adsorption ability of the cement-glass and it could be theoretically predicted accordingly.

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