• Textile Coloration and Finishing
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• v.22 no.4
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• pp.325-331
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• 2010

The alkaline dissolution behavior of sea-island type ultrafine nylon fiber were dependent on the concentration of NaOH and treatment time, and the most appropriate condition for alkaline dissolution was to treat with 20g/l NaOH for 30 min at $80^{\circ}C$. The dyeing properties of sea-island type ultrafine nylon fiber and regular nylon fiber were examined with 3 different types of acid dyes in this study. The dye uptakes of ultrafine nylon fiber were higher than regular nylon fiber because of large surface area per unit mass, which increased as the dye bath pH decreased. The dyeing rates on ultrafine nylon fiber were faster and dye exhaustions were higher than regular nylon fiber, however color strength and rating of wash fastness were lower. It was also found that levelling type acid dye showed fast dyeing rate on both nylon fibers than metal-complex and milling type acid dyes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.1033-1039
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• 2006

The purpose of this study are to evaluated bond, flexural properties and control of plastic shrinkage cracking of crimped type synthetic fiber with amplitude 6 mm and height 1.8 mm reinforced cement based composites. Bond and flexural test were conducted in accordance with the JCI-SF 8 and JCI SF-4 standard, respectively. The plastic shrinkage cracking test was conducted for evaluating the effect of fiber in reducing shrinkage cracking in cement based composites. Test results indicated that the crimped typel synthetic fibers performed significantly better than the straight type fiber in terms of interface toughness and pullout load and the crimped type synthetic fibers improved the flexural toughness of concrete. Also, the increasing the crimped type synthetic fiber volume fraction from 0.00% to 1.00% improved the plastic shrinkage cracking resistance. Specially, the effect of control of plastic shrinkage cracking is excellent at the more than 0.5% fibre volume fraction.

• Textile Coloration and Finishing
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• v.16 no.4
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• pp.1-9
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• 2004

In recent, development of nano fiber has been one of the most active subjects in the world. Nano fiber is defined as a ultra fine yarn with a diameter unit of $10-100\times10^{-9}meter$, which is possible to be produced by an electro-spinning technology. In this study, physical characteristics and dyeing properties of nylon 66 nano fiber were investigated. Nylon 66 nano fiber was dyed with levelling type acid dyes. X-ray diffraction method and DSC analysis were used for the measurement of the degree of crystallization. Analysis of amino end groups was also performed in order to examine a relationship between number of amino groups and its dyeing property as well as water absorption behavior. The maximum exhaustion % of dyes and dyeing rate under various dyeing conditions, such as dyeing temperature and pH in dye bath, along with build-up properties for 2 acid dyes were evaluated. It was found that the degree of crystallization of nano fiber was smaller than that of regular fiber, and amino end groups of nano fiber were less than regular fiber. Half dyeing time of nano fiber was shorter than regular fiber because of the bigger specific surface area. Effect of pH on exhaustion % was small in case of nano fiber. Exhaustion of nano fiber increased with higher concentration of dye.

• Journal of Chest Surgery
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• v.25 no.5
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• pp.451-457
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• 1992

The hollow fiber oxygenator is the most advanced one for the cardiopulmoanry bypass. They have two different types of the hollow fiber systems according to the way how the blood go through the fibers. One is inside blood flow type and the other outside type. In order to find out which is better to prevent blood cell destruction, we selected 40 valve replacing patients and divided them into 2 groups prospectively. In group I [n=20], inside blood flow type[BCM-7a], CO2 excretion is more effective than group II, that is partly because of the relative large surface area of the BCM-7. In group II [n=20], outside blood flow type [MAXIMAa], they have better quality to preserve platelet count. We also studied about several other items such as SaO2, Hemoglobin and RBC, WBC, fibrinogen, LDH, plasma hemoglobin, haptoglobulin and so on. But we cannot find any differences between two groups with any statistical meanings [p<0.05]. We conclude that both of two oxygenators are excellent in the aspects of gas exchange and blood cell preservation.

• Journal of the Korea Concrete Institute
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• v.19 no.2
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• pp.233-239
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• 2007

The main objective of this study was to evaluate the effect of recycled PET fiber made from waste PET bottle on the control of plastic shrinkage cracking of cement based composites. PET is blown as a plastic material and used in a variety products such as a beverage bottle. However, waste PET bottles are thrown after the usage, raising huge problems in terms of the environment. Thus, the research on the method to recycle the PET bottles indicates important aspects in environment and economy. The method to recycle waste PET bottles as a reinforcing fiber for cement based composites is one of effective methods in terms of the recycle of waste PET bottles. In this research, the effect of recycled PET fiber geometry and length on the control of plastic shrinkage was examined through thin slab tests. A test program was carried out to understand the influence of fiber geometry, length and fiber volume fraction. Three type of recycled PET fibers including straight, twist crimped and embossed type. Three volume fraction and two fiber length were investigated for each of the three fiber geometry. Test results indicated that recycled PET fibers are effective in controlling plastic shrinkage cracking in cement based composites. In respect to effect of length of fiber, longer fiber was observed to have efficient cracking controlling with low volume fraction in same fiber geometry while shorter fiber controled plastic shrinkage cracking efficiently as addition rate increase. Also, embossed type fibers were more effective in controlling plastic shrinkage cracking than other geometry fiber at low volume fraction. But, for high volume fraction, straight type fibers were most effective in plastic shrinkage cracking controlling in cement based composites.

• Composites Research
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• v.29 no.5
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• pp.293-298
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• 2016

In this paper, Glass Fiber Reinforced Thermoplastic (GFRTP) for automotive headlight source module was fabricated by compounding and injection molding using PPS (Poly Phenylene Sulfide) resin with glass fiber which has three cross section (round type, cocoon type, flat type). Tensile, flexural, impact properties were investigated on effect of cross section, glass fiber contents. And it was observed flatness, dimensional stability, fluidity depending on glass fiber cross section. As a result, flat glass fiber reinforced thermoplastic's mechanical properties were most excellent. Also, dimensional stability and flatness showed better results when using flat glass fiber.

• Journal of Technologic Dentistry
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• v.42 no.2
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• pp.91-98
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• 2020

Purpose: This study is to compare the flexural strength and modulus by inserting a mesh and stick type fiberglass reinforcement into resin specimens. Methods: Wax specimens (length 64 mm, width 39 mm, thickness 5 mm) are prepared according to ISO 20795-1:2013. Mesh type and stick type glass fiber reinforcements were prepared. The prepared wax specimens were used plaster and flask for investment. The flask was separated and the wax was removed. The heat curing resin was injected into the flask, and then a mesh type and stick type fiberglass reinforcement were inserted. The prepared resin specimen was cut into three equal parts (length 64 mm, width 10 mm, thickness 3.3 mm). The mesh type glass fiber reinforcement (MT group) and the stick type glass fiber reinforcement (ST group) were classified into two groups. The prepared specimen was measured using a universal testing machine (UTM). The data were analyzed by Mann-Whitney U test, and the significance level was set to 0.05. Results: In the flexural strength, the ST group was higher than the MT group, and there was a significant difference between the two groups (p<0.05). In the flexural modulus, the ST group was higher than the MT group, and there was a significant difference between the two groups (p<0.05). Conclusion: The stick-type glass fiber inreased the flexural strength than the mesh-type glass fiber reinforcement.

• Journal of Animal Science and Technology
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• v.66 no.2
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• pp.251-265
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• 2024

Meat derived from skeletal muscles of animals is a highly nutritious type of food, and different meat types differ in nutritional, sensory, and quality properties. This study was conducted to compare the results of previous studies on the muscle fiber characteristics of major porcine skeletal muscles to the end of providing basic data for understanding differences in physicochemical and nutritional properties between different porcine muscle types (or meat cuts). Specifically, the muscle fiber characteristics between 19 major porcine skeletal muscles were compared. The muscle fibers that constitute porcine skeletal muscle can be classified into several types based on their contractile and metabolic characteristics. In addition, the muscle fiber characteristics, including size, composition, and density, of each muscle type were investigated and a technology based on these muscle fiber characteristics for improving meat quality or preventing quality deterioration was briefly discussed. This comparative review revealed that differences in muscle fiber characteristics are primarily responsible for the differences in quality between pork cuts (muscle types) and also suggested that data on muscle fiber characteristics can be used to develop optimal meat storage and packaging technologies for each meat cut (or muscle type).

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.313-318
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• 2001

Compression molding is widely used process for the industrial forming of fiber reinforced plastic articles. Its applications are of an extreme variety and the products range from large parts, such as used in the automotive industry to much smaller objects. In this paper, distribution of fiber orientation by the image processing method for rib type compression molded products of each fiber content is measured. And the effects of fiber content, product size on the orientation state are discussed.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.327-332
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• 2001

It is generally observed that steel fiber reinforced concrete with traditional straight steel fibers overcomes brittle nature of plain concrete by failure mechanisms by fiber pull-out rather than fiber rupture resulting from fiber yielding or concrete fracture at failured surface. Ring type steel fibers in concrete which is confined in concrete matrix and has better orientation, thus, lead to fiber yielding and concrete fracture as well as increase of flexural behavior of concrete more efficiently, Comparative experimental study is performed in order to measure the relative efficiencies of steel fiber reinforced concrete reinforced with two different fibers. It is found that better toughness is obtained from the ring type steel fiber reinforced concrete than from straight steel fiber reinforced concrete under flexural loading.