• Journal of the Korea Furniture Society
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• v.19 no.3
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• pp.172-179
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• 2008

The objective of this study was to investigate the influence of the water repellents' treatment on the water absorptivity and the dimensional stability of Korean red pine wood(Pinus densiflora). The alkylketene dimer(AKD), fluororesin emulsion(Wood-seal, WS), and paraffin wax emulsions(PW25, PW40, and PW1200) were used as water repellents. PW40 and WS were proved as excellent water repellents for pine wood, because the samples treated with these agents showed high contact angles and large reduction in water absorptivities. Also, the dimensional stability(antiswelling efficiency) of pine wood was considerably improved by water repellents treatments, such as PW40 and WS at the pressure of 2MPa. The water repellent treated woods with WS, PW40, and PW1200 at the pressure of 2MPa were relatively stable to the wet-dry cyclic leaching test.

• Interdisciplinary Bio Central
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• v.5 no.3
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• pp.6.1-6.7
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• 2013

Many insects such as mosquitoes cause life-threatening diseases such as malaria, yellow fever and West Nile virus. Malaria alone infects 500 million people annually and causes 1-3 million death per year. Volatile insect repellents, which are detected through the sense of smell, have long been used to protect humans against insect pests. Antifeed-ants are non-volatile aversive compounds that are detected through the sense of taste and prevent insects from feeding on plants. The molecular targets and signaling path-ways required for sensing insect repellents and antifeedants are poorly understood. Transient Receptor Potential (TRP) Ca2+-permeable cation channels exist in organisms ranging from C. elegans to D. melanogaster and Homo sapiens. Drosophila has 13 family members, which mainly function in sensory physiology such as vision, thermotaxis and chemotaxis. G protein-coupled receptors (GPCRs) initiate olfactory signaling cascades in mammals and in nematodes C.elegans. However, the mechanisms of G protein signaling cascades in insect chemosensation are controversial. In this review, I will discuss the putative roles of G protein-coupled receptors (GPCRs) and Transient Receptor Potential (TRP) channels as targets for insect repellents.

• Journal of the Korean Applied Science and Technology
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• v.13 no.2
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• pp.47-53
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• 1996

The procedure to prepare an acrylic emulsion water repellents by blending of arcylic copolymer, activated polyethylene, wax, and emulsifiers was published in the previous paper. After the treatment of the prepared water repellents on a cotton fabrics with and without textile finishing resin, washability, contact angle, tearing strength, and crease recovery were tested. As the result, there were remarkable improvements in physical properties. Proper curing temperature of the synthesized water repellents impellents was $150^{\circ}C$ : proper using concentration was 5wt% : sodium acetate was the best catalyst for water repellents among the used, and proper concentration was 1.0wt%.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.19-22
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• 2002

Rotary mountages are the best mountages among all the mountages that are used in sericultural areas. But to use this mountage more space, separate mounting hall & requires more labour to pickup the matured worms. to over come these problems, self mounting method is adopted to save the time Er labour, But the mounting rate is generally less. To accelerate the mounting rate different repellents viz; saw dust, phytoecdysone, 1% cresol with paddy husk, lime, kaolin, gormalin chaff were used in the present study. The results indicated that highest number of larvae climbed the mountage in 1% cresol with paddy husk, followed by phytoecdysone and lime. It is observed that the use of repellents at wandering stage accilerates mounting rate and did not affect the quality of the cocoons and reeling characters.

• Natural Product Sciences
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• v.3 no.1
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• pp.49-54
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• 1997

We studied the attachment-repelling activity of flavonoids, stilbenes, and their glycosides against the blue mussel Mytilus edulis galloprouincialis. Molecular mechanics calculations have shown that the most stable conformations of potent repellents 29 and 32 were the same. On the basis of these results, structure-activity relationships of these compounds are discussed.

• Journal of the Korean Applied Science and Technology
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• v.11 no.2
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• pp.69-74
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• 1994

Durable softening water repellents for nylon fiber were synthesized, using two compounds: quaternized octadecyl methacrylate-2-diethylaminoethyl methacrylate copolymer as a mother resin of water repellent and quaternized fatty carbamide for improving softness and hydrostatic pressure, of which syntheses were studied in the previous papers. They were blended with waxes and emulsifiers in a variety of ratios and synthesized into water repellent PADWC, and it was nylon taffeta treated with and without textile finishing resin. The synthesized water repellents can be used either or without resin. The optimum curing temperature was 150 to 160$^{\circ}C$ and the optimum concentration was 3 to 5wt%. In the independent and conjunct treatment, the water repellency of nylon taffeta samples have no remarkable changes between initial value and that after three times washing, so these prove that the synthesized compounds are durable water repellent. The water repellency of PADWC-3 and -4 were around 90. Also, comparison of crease recovery and tear strength after repelling treatment showed that the synthesized water repellents have a very high softening effect.

• Korean Journal of Veterinary Service
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• v.33 no.2
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• pp.167-171
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• 2010

Majority of asthma and atopic dermatitis are known to be spontaneously sensitive to house dust mite allergen. Control of house dust mite populations has been principally achieved by using chemical insecticides. But the risk to human health would be a potential problem. Moreover, house dust mite remain as allergens even after death. So, It is more effective method keeping the house dust mites away than killing them. The use of plant-derived repellents has been considered as a promising alternative to chemical repellents. Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. It has insect repellent properties and is an active ingredient in some commercial mosquito repellents. These studies were carried out to investigate repellent effects of Eucalyptus oil against house dust mites and compare lemongrass oil. Eucalyptus oil and lemongrass oil were exposed at different doses (0.2, 0.1, 0.05, 0.025, 0.0125, $0.00625{\mu}l/cm^2$) and different times (1, 3, 6 hours) on house dust mites. The most effective dose of Eucalyptus and lemongrass oils against house dust mites was $0.1{\mu}l/cm^2$ and $0.025{\mu}l/cm^2$. Each repellent effect(%) in most effective dose was 90.3% (Eucalyptus) and 80.8% (lemongrass).

• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.41-46
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• 1996

Durable softening water repellents such as PODCWs were prepared by blending cationized compound of poly(octadecyl methacrylate-co-2-diethylaminoethyl methacrylate), of which synthetic methods were reported in the previous paper, activated polythylene, waxes, and emulsifiers. Water repellency of prepared PODCWs was measured by performing water repellent finish to various fabrics, PODCWs showed a good water repellency for P/C blended fabrics and their repelling tendency was in the order of P/C blended fabrics>cotton fabrics>nylon taffeta. The initial water repellencies of PODCW-1 and PODCW-2 were 100 and $100^{-}$ points, respectively, for P/C blended fabrics. And also, PODCW-1 and PODCW-2 were confirmed as durable water repellents with the results of making little difference of water repellency as ${\pm}5$ point after and before washing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.63-64
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• 2023

In order to reduce the high absorption ratio of spent coffee grounds, this study examined the compressive strength and absorption ratio of mortar replacing coated spent coffee grounds according to the type of water repellent. In order to examine this, as the water repellent used, a silane-based water repellent (fluorine-based water repellent) and an acrylic-based water repellent, which are film-type water repellents, and a silane/siloxane-based water repellent, which are penetration-type water repellents, were used. The spent coffee grounds were coated with each of three water repellents, and mortar was prepared by mixing cement and fine aggregate. As a result of the experiment, the compressive strength and absorption ratio of the mortar replaced with coated spent coffee grounds coated with the film-type water repellent were superior to the penetration-type water repellent. Therefore, in order to reduce the high absorption ratio of spent coffee grounds, a suitable water repellent is a film-type water repellent. Among them, it is judged that the acrylic type has excellent water repellency and is suitable.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.102-108
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• 2015

Agricultural cultivation papers treated with water repellent were investigated in order to analyse mechanical properties and durability. The water repellency was optimal when papers are treated with Wb and Sa water repellents. Also, WCPs with 5% water repellent were more effective than those of 3 and 10%. In addition, water repellency of WCPs with Wb and Sa water repellents were kept constant in correlation with aging time. Finally, WCP with Wb water repellent possesses efficiency in terms of mechanical properties and durability.