• Advances in nano research
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• v.15 no.5
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• pp.441-449
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• 2023

Heavy metals, widely present in the environment, have become significant pollutants due to their excessive use in industries and technology. Their non-degradable nature poses a persistent environmental problem, leading to potential acute or chronic poisoning from prolonged exposure. Recent research has focused on separating heavy metals, particularly from industrial and mining sources. Industries such as metal plating, mining operations, tanning, wood and chipboard production, industrial paint and textile manufacturing, as well as oil refining, are major contributors of heavy metals in water sources. Therefore, removing heavy metals from water is crucial, especially for safe water supply in swimming and water sports. Iron oxide nanoparticles have proven to be highly effective adsorbents for water contaminants, and efforts have been made to enhance their efficiency and absorption capabilities through surface modifications. Nanoparticles synthesized using plant extracts can effectively bind with heavy metal ions by modifying the nanoparticle surface with plant components, thereby increasing the efficiency of heavy metal removal. This study focuses on removing lead from industrial wastewater using environmentally friendly, cost-effective iron nanoparticles synthesized with Genovese basil extract. The synthesis of nanoparticles is confirmed through analysis using Transmission Electron Microscope (TEM) and X-ray diffraction, validating their spherical shape and nanometer-scale dimensions. The method used in this study has a low detection limit of 0.031 ppm for measuring lead concentration, making it suitable for ensuring water safety in swimming and water sports.

• Textile Coloration and Finishing
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• v.35 no.3
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• pp.169-178
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• 2023

The extended use of polyester nowadays has increased the amount of waste polyester (PET) released into the environment. Although these materials don't directly harm living things or the ecosystem, their inability to biodegrade remains one of the major global threats, driving up the amount of solid waste made up of PET. Environmental concerns have approved an increasing interest in recycled PET however the production of recycled PET with sufficient mechanical properties is still a challenge. Recycled Polyester (rPET) yarns are inexpensive and have the potential to acquire better mechanical characteristics through physical treatments, particularly by using technically simple method like uniaxial drawing. This study inspected the drawn behavior of virgin PET yarns and rPET yarns under various drawing parameters by first analyzing the initial material characteristics of both yarn. The impact of stretching on mechanical and morphological properties was also investigated. The results showed that virgin PET has better properties than rPET yarn; however, mechanical properties resembling virgin PET are achieved after optimizing the draw ratio.

• Journal of the Korea Fashion and Costume Design Association
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• v.25 no.4
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• pp.13-28
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• 2023

The purpose of this study is to analyze the characteristics of hippie style in emerging brands pursuing the hippie spirit, examine the changes in hippie style, and apply them to the design development process to propose a hippie style design that reflects contemporary characteristics. The research method of this study was used to grasp the characteristics and current status of hippie style based on a literature review and prior research. Through the analysis of Bode and Story mfg, a new brand that reflects the hippie spirit, the design expression methods and characteristics of modern hippie style were derived, and based on the analysis, the design of the 3D CLO virtual outfit was developed. The results of the study are as follows. First, in addition to the use of eco-friendly materials, the digital technology of the CLO 3D program was applied to the design development process, which made it possible to increase sustainability from the production process. Second, by creating a retro design centered on a striped pattern expressing freedom, revolution, and equality, and a handcrafted design based on a tie-dye pattern, the design was able to express the hippie spirit of loving nature, and through this, a new direction of eco-friendly and modern fashion design was presented.

• Tribology and Lubricants
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• v.40 no.3
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• pp.91-96
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• 2024

Recently, extensive studies have been carried out to enhance various performance aspects such as the durability, lifespan, and hardness by combining diverse materials or developing novel materials. The utilization of superhydrophobic surfaces, particularly in the automotive, textile, and medical device industries, has gained momentum to achieve improved performance and efficiency. Superhydrophobicity refers to a surface state where the contact angle when water droplets fall is above 150°, while the contact angle during sliding motion is smaller than 10°. Superhydrophobic surfaces offer the advantage of water droplets not easily sliding off, maintaining a cleaner state as the droplets leave the surface. Surface modification involves two fundamental steps to achieve superhydrophobicity: surface roughness increase and surface energy reduction. However, existing methods, such as time-consuming processes and toxic organic precursors, still face challenges. In this study, we propose a method for superhydrophobic surface modification using lasers, aiming to create roughness in micro/nanostructures, ensuring durability while improving the production time and ease of fabrication. The mechanical durability of superhydrophobic samples treated with lasers is comparatively evaluated against chemical etching samples. The experimental results demonstrate superior mechanical durability through the laser treatment. Therefore, this research provides an effective and practical approach to superhydrophobic surface modification, highlighting the utility of laser treatment.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.93-100
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• 2002

Cocoon production, which is a representative of traditional sericulture shifted into silkworm powder production in the spring of 1995. This, infect, signifies the change from the dress-centered textile business to the bio-industry and the functional resource industry. One of the most outstanding shifting is utilization of silkworm larvae for anti-diabetic agent. In Asian countries including Korea, silkworm powder derived from the domestic silkworm (Bombyx mori L.) has long been favored for anti-diabetic agent, but its efficacy was not tested until last decade by modern scientific methods. In this article, we reviewed the major researches on the silkworm powder as a blood glucose-lowering substance. After the beginning test of the efficacy of silkworm powder by a cooperative research between Department of Sericulture and Entomlogy, NIAST, RDA and Kyung Hee University, substantial data have been accumulated so far, In a serial experiment to select best condition, the fifth instar larvae prepared by freeze dry method turned out to have the best blood glucose-lowering effect. In the pharmacological experiment to understand the mechanism of silkworm powder in small intestine, the silkworm powder turned out to inhibit the activity of ${\alpha}$-glucosidase, by competitively binding to $\alpha$-type disaccharides. The animal experiment showed that the extract of silkworm powder prevents a rapid increase of blood glucose level after meal and prevents hunger and law blood glucose level during empty stomach. In the experiment to isolate the major component of silkworm powder, which exerts blood glucose-lowering effect, 1-deoxynojirimy-cin (DNJ) was eventually mass-purified, and it turned out that DNJ isolated from silkworm powder was excellent in its blood glucose-lowering effect. In the experiment to understand the personal difference of the efficacy of the silkworm powder, clinical candidates were divided on the basis of the criterion of traditional Chinese medicine: Tae-Yang, Tae-Um, So-yang, and So-Um. The result showed that silkworm powder has a tendency to reduce blood glucose level at fasting and at 2 hours after meal, and this trend was somewhat obvious in the Tae-Um body type. In summary, we reviewed scientific papers on the efficacy of silkworm powder and its purified DNJ as a blood glucose-lowering agent. These suggest that silkworm powder truly possesses blood glucose-lowering effect as documented in the traditional Chinese medicine, although further researches will be required to develop them as "medical" resource instead of functional food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1905-1911
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• 2015

Melanin is one of the most important factors affecting skin color. Melanogenesis is the bioprocess of melanin production by melanocytes in the skin and hair follicles and is mediated by several enzymes, such as tyrosinase, tyrosinase related protein (TRP)-1, and TRP-2. Convenient enzymatic transformation of the simple phenol pyrogallol with polyphenol oxidase originating from pear to an oxidative product, purpurogallin, was efficient. The structure of the pyrogallol oxidation product was identified on the basis of spectroscopic methods. The biotransformation product purpurogallin showed significant inhibitory effects against both melanin synthesis and tyrosinase activity in a dose-dependent manner in B16 melanoma cells. In addition, purpurogallin significantly attenuated melanin production by inhibiting TRP-1, and TRP-2 expression through modulation of their corresponding transcription factors, and microphthalamia- associated transcription factor in B16 cells. Consequently, purpurogallin derived from convenient enzymatic transformation of pyrogallol might be a beneficial material for reducing skin hyperpigmentation.

• Clean Technology
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• v.20 no.2
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• pp.103-107
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• 2014

Acrylic acid is a commodity chemical which is applicable for various industries such as polymer and textile industry. Currently, it has been produced by chemical synthesis from petroleum. However, due to the high price of petroleum and global $CO_2$ emission, renewable materials such as sugar are interesting alternative carbon sources for the biological production of acrylic acid. For an economic production of acrylic acid from renewable carbon sources, a cost effective separation process for acrylic acid should be needed. In this study, reactive extraction by TOA (tri-n-octylamine) was used for the recovery of acrylic acid from its aqueous solutions. The effects of polarity of diluents and concentration of TOA on extraction equilibrium were investigated. The extraction efficiency was proportional to concentration of TOA and polarity of diluents and its value was more than 95% in the case of sufficient concentration of TOA. From IR spectroscopy, it was concluded that the ratio of (1,1) acid-amine complex was increased and the ratio of acid dimer was decreased with concentration of TOA. Equilibrium model based on IR spectroscopy was well fitted with experimental data.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.413-419
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• 2019

In the recent, as a world demand of energy resources has been transformed from fossil fuels to hydrogen-based clean energy resources, a huge attention has been attracted to increase the performance and decrease a production cost of core materials in fuel cell technology. The utilization of reinforced composite membranes as electrolytes in the polymer electrolyte membrane fuel cells can reduce the use of high cost perfluorosulfonic acid (PFSA), mitigate the cell impedance, and improve the dimensional stability as well as the interfacial stability, giving rise to achieve both an improved performance and a reduction of production costs of the fuel cell devices. In this study, we investigate the effects of physical characteristics and cell performances according to the various ionomer solvents in the solution based manufacturing process of reinforced composite electrolyte membrane.

• Journal of Fashion Business
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• v.6 no.1
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• pp.137-154
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• 2002

It's not easy to renew old brand of over 50 years history to the tastes of new consumer of our time. Most of national brands that has a history of some 20 years in Korea have strove for continuation and growth of brand to no avails, which can be taken as a good example of current situation. For instance, C company, one of the National brand of US which has a history of 51 years, has made its position secure as a fashion group and based itself on a sound foundation by establishing new marketing strategy and completing successful brand renewal in the process of strategic M&A with Italian company. Those successful marketing strategies are as follows. 1) they regarded both market and consumer oriented marketing activity as company's highest priority strategy and put great emphasis upon concentration on target market and reestablishment of brand image of business casual wear. 2) Setting up and operating planning team composed of merchandizer alone in Milano, they set the direction of plan on the basis of concentrated research on potential item in market according to thorough market research done by buying office in Korea, branch office in Hong Kong and buyer in US prior to blueprint planning for season. 3) Great emphasis was placed on business which focused on intensive presentation of basic key item for apparel career women who are main consumer group in the midium-low prices market in US and on supplementation of size and color. they named this line 'collectibles' and helped their customer develop their own clothes plan without worrying about the change of color and fabric by supporting same fabric and color throughout the year and enabled them to add variation easily by supplementing new trend item. 4) Company set black as a main color that lots of apparel career women find easy to care and to express their own image and presented them with pebble which belongs to navy and beige and added fashion color such as wine and brown etc as season goes by. They constructed basic line in order for their customers to coordinate purchased item with new one or to add them to present collection, and to achieve efficient sale by setting up strategy which allows this cross coordination and changing pattern occasionally. 5) Though basic jacket for 99$, short slim skirt for 49$ are products within midium-low prices range, in the material planning stage aiming at production of item that has both resonable function appealing to consumer and is fashionable, synthetic material had to be used as a main source due to price competitiveness. Despite this situation, considering comfortable sense of fit and refined drape of silhouette that has no sign of cheap material, whole collectible line was divided into two items, which contributed to reduction of cost. In case of material that is composed of triacetate and polyester in 70 to 30 ratio, was used up to 4 million yard, which allowed drastic curtailment of cost accompanied by concentration. In case of 'collectibles' line, using Korean material mainly, C company chose to have their product sewed in Southeast Asian countries where transportation is well developed and both productivity and quality verified by operating global production system which aiming at cutdown of cost through outsourcing production from the country where labor cost is low and getting finished product. Polarization between present consumers telling us that consumers with the mind of middle classes in the past no longer exists between consumers who seek after only fine article of highest quality and wise consumers who are sensible enough to judge bubble on correlation between price and quality. To cope with this change in new consumer mind, apparel makes changing their policy so as to produce item that has reasonable quality and falls within affordable price range anywhere in the world. and they're striving to get out of difficult situation by operating global marketing strategy which stresses separation of planning, production and sale and sensibility of fashion shared worldwide. The marketing strategy of C company can be exemplified as a successful one.

• Composites Research
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• v.36 no.1
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• pp.1-15
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• 2023

Demand for energy consumption reduction is increasing according to the development expectations of future mobility. Lightweight structural materials are known as a method to reduce greenhouse gas emissions and improve energy efficiency. In particular, fiber reinforced polymer composite (FRP) is attracting attention as a material that can replace existing metal alloys due to its excellent mechanical properties and light weight. In this paper, industrial applications and research trends of carbon fiber reinforced composites (CFRP, carbon FRP) and self-reinforced composites (SRC) were reviewed based on the reinforcement, polymer matrix, and manufacturing process. In order to overcome the expensive process cost and long manufacturing time of the epoxy resin-based autoclave method, which is mainly used in the aircraft field, mass production of CFRP-applied electric vehicles has been reported using a high-pressure resin transfer molding process including fast-curing epoxy. In addition, thermoplastic resin-based CFRP and interface enhancement methods to solve the recycling issue of carbon fiber composites were reviewed in terms of materials and processes. To form a perfect matrix-reinforcement interface, which is known as the major factor inducing the excellent mechanical properties of FRP, studies on SRC impregnated with the same matrix in polymer fibers have been reported. The physical and mechanical properties of SRC based on various thermoplastic polymers were reviewed in terms of polymer orientation and composite structure. In addition, a copolymer matrix strategy for extending the processing window of highly drawn polypropylene fiber-based SRC was discussed. The application of CFRP and SRC as lightweight structural materials can provide potential options for improving the energy efficiency of future mobility.