• Journal of the Korean Wood Science and Technology
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• v.48 no.3
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• pp.315-325
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• 2020

Boron compound had many advantages as wood preservative, but it was prone to leaching. Improving boron preservation was required to extend the service life of fast growing and low durability red jabon (Antochephalus macrophyllus) hardwood. This study aimed to evaluate the dimensional stability, color change and durability of modified red jabon wood by double impregnation with boron and methyl methacrylate (MMA) and heat treatment. Impregnation I used boric acid or borax, and impregnation II used MMA, while heat treatment used temperatures of 90 ℃ or 180 ℃ for 4 hours. The dimensional stability, leachability, water absorption, color change and decay resistance of modified red jabon wood were tested. The results showed that MMA impregnation increased the dimensional stability of red jabon wood, while the leaching and water absorption in the wood significantly reduced. Heating at 180 ℃ caused less water absorption and higher dimensional stability of the wood than that of heating at 90 ℃. Impregnation with boric acid and MMA followed by heating at 90 ℃ resulted in the highest wood ASE, 89.9%. The color change (∆E^*) of wood increased significantly after MMA impregnation and heating at 180 ℃. Boric acid impregnation caused more resistant wood than borax impregnation against decay fungi and termites. Impregnation with boric acid and MMA followed with heating at 180 ℃ increased significantly the wood resistance against decay fungi and termites.

• Journal of the Korean Ceramic Society
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• v.26 no.6
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• pp.729-736
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• 1989

This study aims to reinforce concrete structure by impregnation of molten sulfur. The improved properties of sulfur impregnated concerete were confirmed by compressive strength test and water proof effect. Following variables were adopted to evaluate impregnation parameters ; 1) the effect of water content in concrete structure (0-8%) 2) impregnation time of molten sulfur(0-22hr) 3) impregnation temprature of molten sulfur(13$0^{\circ}C$, 14$0^{\circ}C$). In partial ponding experiments, the concrete specimen of sulfur impregnated by 2wt% yields 1.5 times higher value of compressive strength than that of control one(non-impregnated concerte). In complete ponding experiments, the mortar specimen of slufur impregnated by 12-14wt% yields 2-3 times higher value of compressive strength than that of control one (non-impregnated mortar). From the examination of X-ray diffractions, $\alpha$-sulfur was found in concrete pores. Homogeneous impregation of molten sulfur into concrete pores was also identified with poresize analysis and micrographs of SEM.

• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.327-333
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• 2015

To measure the dimensional stability of three softwoods by vacuum pressurization of water soluble melamine-formaldehyde (MF) resin impregnation process, properties of resin treated compressed woods (compregs) were measured after impregnating the water soluble MF resin into three coniferous wood species for different impregnation times and resin concentrations. As the resin concentration was higher and impregnation time was longer, coefficients of volumetric shrinkage and anti-volumetric swelling efficiency increased, but coefficients of volumetric swelling, anti-volumetric swelling efficiency and absorption decreased. Also, weight percent gain increased remarkably as the resin concentration was high, but there was no uniform relationship with impregnation time.

• Journal of the Korean Ceramic Society
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• v.37 no.8
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• pp.760-767
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• 2000

Recently, the protection of construction is demanded with environmental pollution. These protect modes are use of concrete admixture, coat of protective polymer and impregnate of surface with chemicals etc. The most widely used impregnation is economical and effective. The define of Impregnation for construction protect is reacted in and consolidated substrate after absorbed. The impregnation agents are Polyesters, Acrylic monomers, Epoxy and Silicone derivatives. Commonly, because the Silane has good water repellency and environmental advantages that it widely used to water proofing agents, dampproofing agents and absorption reducer for concrete of bridges. When application of Silane, it occurs pollution and harmfulness as included organic solvent. The manufactures have tired to emulsification of Silane for the reducing of the defects. The Silane emulsion is vary unstable and does not stored long periods, and it is diminished in good properties with internal reaction. In this study we tried to emulsification of Silane for effectiveness improvement and reduce pollution and hazard and discussed properties variation of emulsion. The Silane emulsions are achieved emulsifying with W/O and O/W type surfactants. It used 0.24% PVA as protective colloid and stable phase is creamy. The creamy Silane emulsion performance as the penetration depth and water absorption rate are above 4 mm and below 0.1. It stable about 6 month at room temperature.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.4 s.107
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• pp.41-48
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• 2004

To make a basepaper for multipurposed seed paper, old news print (ONP) and mixed office waste paper (MOW), modified and unmodified with a commercial cellulase, were investigated. Each handsheet was applied with different chemicals such as insecticides, germicides and herbicides. The interactions behaviors of chemicals used with base papers were evaluated by means of the contents of chemicals impregnation and dissolving behaviors in water and soil. The ONP and MOW treated with the cellulase had higher impregnation and dissolving capacities in both water and soil than untreated ONP and MOW. However, the modified ONP showed lower impregnation and dissolving capacities compared to the modified MOW. The content of impregnation of chemicals would be affected with the degree of microfibrils produced by the modification treatment. Otherwise, dissolving capacities of chemicals depend on the affinity of the residual lignin in the paper.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.6
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• pp.425-435
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• 2020

Numerous chemical modifications on activated carbon such as acidic conditioning, thermal treatment and metal impregnation have been investigated to enhance adsorption capacities of micropollutants in water treatment plants. In this study, chemical modification including acidic, alkaline treatment, and iron-impregnation was evaluated for adsorption of 2,4-dichlorophenol (2,4-DCP). For Fe-impregnation, three concentrations of ferric chloride solutions, i.e., 0.2 M, 0.4 M, and 0.8 M, were used and ion-exchange (MIX) of iron and subsequent thermal treatment (MTH) were also applied. Surface properties of the modified carbons were analyzed by active surface area, pore volume, three-dimensional images, and chemical characteristics. The acidic and alkaline treatment changed the pore structures but yielded little improvement of adsorption capacities. As Fe concentrations were increased during impregnation, the active adsorption areas were decreased and the compositional ratios of Fe were increased. Adsorption capacities of modified ACs were evaluated using Langmuir isotherm. The MIX modification was not efficient to enhance 2,4-DCP adsorption and the MES treatment showed increases in adsorption capacities of 2,4-DCP, compared to the original activated carbon. These results implied a possibility of chemical impregnation modification for improvement of adsorption of 2,4-DCP, if a proper modification procedure is sought.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.462-467
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• 1997

The DIS process(dewatering and impregnation soaking process) are using for dewatering of food materials at room temperature. And the DIS process are resulted in diffusion process as well as dewatering phenomena. During the DIS process, plasmolysis or cytorrhysis was happened by according to solute size. A tissue state of food material was very important variables for movement of water or solute, and running conditions are important for dewatering and impregnation. And models for DIS process were fundamentally given by Fick's law at unsteady state or mass balance. For example, Bicompartmental Model was given for quantification of water loss and solid gain.

• Journal of the Korean Wood Science and Technology
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• v.47 no.2
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• pp.189-199
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• 2019

This study addresses the biorefinery feedstock from Pinus densiflora. This raw material is a major tree species in the Republic of Korea; it is renewable, has cost-effective, and is readily available. In this study, steam explosion of P. densiflora was performed in a reactor at $225^{\circ}C$ and with 1 to 13 min reaction times with or without previous water impregnation. The combined severity factor (Ro), which is an expression relating the reaction temperature and reaction time used in the steam explosion treatment, ranged from 3.68 to 4.79. The influence of both impregnation and steam explosion conditions were investigated by examining color variations, chemical composition, and mass balance on the pretreated solids. The results showed that steam-exploded P. densiflora that was not impregnated with water exhibited significantly darker color (chroma 28.8-41.4) than water-impregnated and steam-exploded P. densiflora (chroma 18.8-37.3). The increased ${\alpha}$-cellulose and lignin contents were detected as the severity factor increased. Furthermore, the ${\alpha}$-cellulose and lignin contents in the non-impregnated/steam-exploded P. densiflora were higher than those in the water-impregnated/steam-exploded P. densiflora. However, the decreased holocellulose content was detected as the severity factor increased. In mass balance, the holocellulose yield from water-impregnated/steam-exploded P. densiflora was higher than that from the non-impregnated P. densiflora.

• Journal of the Korean institute of surface engineering
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• v.53 no.6
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• pp.300-305
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• 2020

Corrosion of reinforcement steel rebar is a serious problem in a wide range of concrete application for buildings and infrastructures. Hydrophobizing surface treatments, such as self-assembled monolayer coating, edible oil-impregnation and silicone oil-impregnation were applied to solidified concrete. The hydrophobizing of concrete significantly reduces an absorption and transportation of water toward a steel rebar in concrete, so that the corrosion resistance of the steel rebar. In particular, the silicone oil-impregnation not only forms the hydrophobic monolayer on the concrete but also fills the inter-connected pores of concrete, thus the corrosion of steel rebar is significantly inhibited compared to the self-assembled monolayer coating and edible oil-impregnation. Therefore, the silicone oil-impregnation can be a promising candidate for preventing corrosion of steel rebar in concrete for durable performance and safety.

• Journal of the Korean institute of surface engineering
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• v.54 no.2
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• pp.90-95
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• 2021

Surface modification technique enabling the control of condensation provides various benefit in various engineering systems, such as heat transfer, desalination, power plants, and so on. In this study, lubricant oil-impregnation into Teflon-coated nanoporous anodic oxide layer of aluminum to enhance a de-wetting and mobility of water droplet on surface. Due to the surface treatment improving water-repellency, the condensation mode is changed to dropwise, thus the frequency of sliding condensed water droplet on surface is increased. For these reasons, the surface of oil-impregnated Teflon-coated nanoporous anodic aluminum oxide shows significantly enhanced condensation heat transfer compared to bare aluminum surface. In addition, the porosity of anodic aluminum oxide affected the mobility of water droplet even with oil-impregnation and Teflon-coating, indicating that the optimization of porous structure of anodic oxide is required for maximizing the condensation heat transfer.