• Membrane and Water Treatment
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• v.13 no.1
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• pp.21-28
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• 2022

The use of plastics in our everyday lives have been drastically increased during the last few decades. However with the usage of commercial plastic products there is a possibility of microplastic consumption, due to the fragmentation of the products. Additionally, the potential for microplastic ingestion may also be increased by using damaged products. Hence, the current study was conducted to understand the potential release of micro/nano plastics and organic matter from damaged teabags. To check the leakage tendency, the amount of damage to the tea bags from 1-10 cm were tested along with temperatures of 25-70℃, and exposure times from 5 min to 1 hr was tested. Release of fibrous micro/nanoplastics, and organic leachate from the damaged teabags were observed to understand the outflow conditions. Results showed that with the increased degree of damage, temperature, and exposure time increased the release of fiberous matter, where the increase of temperature, and exposure time increased organic leachate. Additional analysis confirmed the leachate of nylon polymers into the heated water.

• Korean Journal of Food Science and Technology
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• v.6 no.1
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• pp.42-54
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• 1974

Twenty-six food products which are commonly consumed in Korea were classified according to the method of Oldfield et al., based on the physical and rheological properties, and subjected to the measurement of textural characteristics by the General Foods Texturometer. It was found that the measurement conditions, texturometer curves and parameters differed depending on the food group such as gelatinous, heterogeneous gelatinous, fatty emulsion, cellular textured, fibrous, spongy and porous solid food products. Diverse texturometer curves were obtained from the same kinds of food products, especially among the porous solid food products.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1659-1676
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• 2002

Ruminant animals develop a diverse and sophisticated microbial ecosystem for digesting fibrous feedstuffs. Plant cell walls are complex and their structures are not fully understood, but it is generally believed that the chemical properties of some plant cell wall compounds and the cross-linked three-dimensional matrix of polysaccharides, lignin and phenolic compounds limit digestion of cell wall polysaccharides by ruminal microbes. Three adaptive strategies have been identified in the ruminal ecosystem for degrading plant cell walls: production of the full slate of enzymes required to cleave the numerous bonds within cell walls; attachment and colonization of feed particles; and synergetic interactions among ruminal species. Nonetheless, digestion of fibrous feeds remains incomplete, and numerous research attempts have been made to increase this extent of digestion. Exogenous fibrolytic enzymes (EFE) have been used successfully in monogastric animal production for some time. The possibility of adapting EFE as feed additives for ruminants is under intensive study. To date, animal responses to EFE supplements have varied greatly due to differences in enzyme source, application method, and types of diets and livestock. Currently available information suggests delivery of EFE by applying them to feed offers the best chance to increase ruminal digestion. The general tendency of EFE to increase rate, but not extent, of fibre digestion indicates that the products currently on the market for ruminants may not be introducing novel enzyme activities into the rumen. Recent research suggests that cleavage of esterified linkages (e.g., acetylesterase, ferulic acid esterase) within the plant cell wall matrix may be the key to increasing the extent of cell wall digestion in the rumen. Thus, a crucial ingredient in an effective enzyme additive for ruminants may be an as yet undetermined esterase that may not be included, quantified or listed in the majority of available enzyme preparations. Identifying these pivotal enzyme(s) and using biotechnology to enhance their production is necessary for long term improvements in feed digestion using EFE. Pretreating fibrous feeds with alkali in addition to EFE also shows promise for improving the efficacy of enzyme supplements.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.5 s.108
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• pp.44-52
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• 2004

It is well known that Korean traditional Hanji have lots of predominant physical and optical properties such as high density, high air permeability, long lasting quality and lightness. The paper-making raw materials of traditional Korean Hanji are the bast fibre cooked from the Korean paper mulberry as a fibrous materials and sticky aqueous material from the root of Hibiscus anihot L. as additives for good dispersion of stock. Additionally, the mechanical properties of Hanji varies according to the cooking methods of bast tissues of Korean paper mulberry, the treatment methods of fibrous raw materials such as bleaching and refining, the wet formation types of sheet-making such as 'Oebal-chiji' and 'Ssangbal-choji', and the finishing treatment like stamping. This study was carried out to investigate and evaluate the quality properties of Korean traditional hand-made Hanji, and compared with commercial machine-made paper and modified prepared sheets. The physical quality comparisons of different kinds of Hanji were focused on the methods of hand-sheet making, the types of raw materials, the treatment of stamping, and the properties of ink reception and spreading.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.7
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• pp.562-568
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• 2014

This study aimed to identify changes in the physical properties of artificial mineral-fiber materials used as building insulation that had been installed in the outer walls of buildings for a long time. To achieve this goal, glass fiber and rock wool were collected from outer walls in actual buildings and their acoustic and thermal performances were measured. These were compared with measurements from similar products manufactured recently. The results showed that old, used samples had a lower sound absorption coefficient compared to recently manufactured materials. The old samples also displayed increased compressibility compared to new materials. For example, the compressibility difference for glass wool was 7.32 mm. Old samples had a dynamic stiffness $1.28MN/m^3$ higher than new material samples. The thermal conductivity of both old and new samples increased within creasing temperature. They showed similar results at temperatures between 0 and $20^{\circ}C$.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2A
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• pp.297-304
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• 2008

It is well known that cracks in concrete decrease permeability and durability of concrete because cracks enhance the penetration of water or corrosive chemicals like as chlorides, carbon dioxides, sulfates and some others. But some of cracks in hardened cements may be sealed in case of contacting water. This phenomenon is called "self healing" and it has a close relation to hydration products newly formed on surfaces of cracks. Many studies on self healing in concretes commonly showed that CSH gel has been observed on crack surfaces. And some studies have reported that calcium hydroxides and ettringite were observed as well as CSH gel on crack surfaces. This study was carried out to investigate hydration products formed by self healing process and also examine the influence of waterproof admixture for concretes on self healing of cement. As a result of XRD, DSC, SEM and EDX analysis of crack surfaces, it was found that self healing of cement was related to CSH gel, calcium hydroxides and ettringite. And waterproof admixture increased fibrous (needle-like) hydration products which were in network form. It is estimated that such fibrous products are effective for self healing process of cement system.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.3
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• pp.55-62
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• 2015

Paper mulberry fibers have been used as fibrous raw materials for manufacturing traditional handmade paper, hanji for a long time. Compared to wood pulp fibers, pulp fibers from mulberry bast tissue have some benefits in physical and chemical properties due to their high D.P (degree of polymerization), M.W (molecule weight) and long fiber length. Specially, Korean handmade hanji shows outstanding characteristics in mechanical tensile strength, folding endurance, flexibility and long sustainable conservation properties. Therefore, hanji is widely applied to daily supplies, hygienic goods, medical supplies, clothing industries and so on. Recently, the potential demand of mulberry pulp fibers is more and more increased on the strength of high application fields. This study was focused on the possibility of wastewater recycling in unit operation systems for the development of automated mass production line. The properties and environmental loads of wastewater from debarking, cooking, bleaching and screening process were analyzed by means of COD, conductivity, turbidity and solid materials. The wastewater from debarking and cooking process was comparatively high in pollution load, and would be treated by additional approaches of chemico-physical method.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.94-102
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• 2014

The physical and chemical properties of recycled fibers from mixed waste paper are more and more deteriorated because of unknown history of recycling times. In order to improve the mechanical properties of liner paper, the recycled fibers from wasted cotton clothes were used in papermaking process, and their applicabilities were evaluated in several points of fiber modification. Thus, two kinds of fiberizing methods from waste cotton clothes were considered by using rotary sandpaper and grinder mill. Finally, the rotary sandpaper method was relatively desirable in preserving longer fiber length and fibrillated fiber surface. The recycled cotton fibers by swelling treatment with NaOH and bleaching with reductive chemicals were mixed with OCC fibers, and the handsheets were prepared to basis weight of $80g/m^2$ and evaluated the mechanical properties of paper. The fibrous properties showed outstanding results in freeness and WRV improvements by alkali treatment and high brightness by reductive bleaching treatment. The physical and mechanical properties of sheet by mixing OCC fibers and recycled cotton fibers were also highly improved in tensile, burst strength and specially folding resistance.

• Journal of Fashion Business
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• v.25 no.5
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• pp.99-113
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• 2021

This study aimed to produce sensors for measuring thigh motor skills. A textile stretch sensor was manufactured using a CNT(Carbon Nano Tube) 0.1 wt% water SWCNT(Single-Walled Carbon Nano Tube) solution, and different designs were applied to increase the sensitivity of the sensor, and different GF(Gauge Factor) values were compared using UTM devices. The same design was applied to fabrics and weaves to observe changes in performance according to fibrous tissue, and the suitability of sensors was determined based on tensile strength, elongation, and the elongation recovery rate. Sensitivity was found to vary depending upon the design. Thus the manufactured sensor was attached to a pair of fitness pants as a prototype, divided into lunge position and squat position testing, and the stretch sensor was used to measure thigh movements. It was shown that stretch sensors used to measure thigh motor skills should have light and flexible features and that elongation recovery rates and tensile strength should be considered together. The manufactured stretch sensor may be applicable to various sports fields that use lower limb muscles, wearable healthcare products, and medical products for measuring athletic ability.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.2
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• pp.58-66
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• 2012

Brewers grain is a byproduct of beer brewing and consists primarily of grain husks, pericarp, and fragments of endosperm. Although this material is consumed by animals and used as fertilizer, a large amount of brewers grain is simply discarded. Therefore, new methods for utilizing this fibrous resource should be pursued. In this study, we examined the potential utilization of brewers grain as an additive in the paperboard industry by determining the chemical composition of brewers grain and the physical properties of brewers grain powders after grinding with two types of grinders. We found that brewers grain had a lower holocellulose content and higher lignin content and intermediate ash content when compared to other biomass materials, and did not contain any contaminants that would interfere with the papermaking process. Particles had a higher fiber length, less fiber width, and narrower shape factor distribution when ground by a blender type grinder than by a pin crusher type grinder. The blender type grinder was concluded to make regular brewers grain particles appropriate for papermaking.