• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.4
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• pp.158-163
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• 2014

Mineral fiber, or be called mineral wool when it assembles in large amounts, is a kind of wide applied man-made material with excellent thermal and acoustic insulation properties. In this work, mineral fiber was produced via melt spinning method by using iron blast furnace slag as raw material. Two critical experimental parameters for fabrication were investigated: melt pouring temperature and rotating speed of spinning wheels. The mineral fiber produced under the condition of melt pouring temperature $1500^{\circ}C$ and spinning speed 4000 rpm, showed the smoother surface and most quality, while the others had rough surfaces or with heavy shots. In general, mineral fibers with the size in the range of $12{\sim}49{\mu}m$ in diameter and 8~130 mm in length can be fabricated by this method, and the production rate is more than 34 wt.%, which could be up to 57 wt.% at maximum.

• Journal of Nutrition and Health
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• v.25 no.6
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• pp.429-449
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• 1992

The consumption of foods rich in TDF should not be associated with impaired mineral absorp-tion and long-term mineral status. In surveys of populations consuming high amounts of TDF e.g Third World populations and vegetarinas gross deficiencies in mineral nutrition have not been noted. If mineral status is low among these groups it is most likely caused by the inadequacy or imbalance of the diet and not by the TDF. The key word is interaction which should be inte-rpreted in dietary imbalances that produce nut-rient deficiencies. There are no strong data to support the concept that TDF inhibits mineral absorption through a binding chelation mechanism. Limited data sug-gest that positively charged groups on polymers such as chitosan and cholestyramine will decrease iron absorption in humans and animals. Because TDF does not contain positively charged groups future research should be directed at the possible role of protein consumed along with TDF and the combination of effects on mineral nutrition Phytic acid is acknowledged as a potent chela-tor of zinc. However its association with zinc and its propensity to lower Zn bioavaiability may enhance the absorption of other elements notably copper and iron. The importance of interactions among nutrients including TDF will gain addi-tional attention in the scientific community. Soluble and insoluble dietary fiber function di-fferently in the intestine. Insoluble fibers accele-rate movement through the intestine. Soluble die-tary fibers appear to regulated blood concentra-tions of glucose and cholesterol albeit by some unknown mechanism. In creased viscosity produ-ced by the SDF in the intestine may provide an explanation of how this class of polymers affects plasma glucose cholesterol and other nutrients. Employing a double-perfusion technique in the rat we demonstrated that viscosity produced by SDF will delay transfer of zinc into the circulatory system. This delayed absorption should not be interpreted as decreased utilization. A great deal of additional research is required to prove the importance of luminaly viscosity produced by SDF on slowing nutrient absorption or regulating bllod nutrient homeostasis. Increased intake of TDF in the total human diet appears desirable. A dietary intake of 35g/day should not be considered to have a negative effect on mineral absorption. It is important to educate people that an intake of more than 35g TDF/day may cause an imbalance in the diet that can adve-rsely affect mineral utilization. Acknowledgments. Appreciation is given to Dr. George V. Vahouny(deceased) who was intense a great competitor in and out of science and who gave the author inspiration Portions of this work were supported by the University of Missouri Ag-ricultural Station and by a grant from the Univer-rch Support Grant RR 07053 from the National Institutes of Health. Contribution of the Missouri Agriculatural Experiments Station Journal Series No. 10747.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.894-899
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• 2012

In recent years, recycling process has come to be necessary for separating metals, glass fibers and polymer from WPCBs (waste printed circuit boards) due to an increasing amount of electronic device waste. In this study, dimethylformamide (DMF) and attrition mill reactor were used to separate the component such as metals, glass fiber and epoxy resin from WPCBs. Separation of glass fiber from WPCBs was carried out under stirring rates 300~600 revolution per minute (rpm) for 1~2 h as the various agitator. The recycled glass fibers (RGF) were analyzed by thermogravimetric analyzer (TGA) for degree of separation of epoxy resin in the WPCBs. The degree of separation of epoxy resin of WPCBs increased in attrition mill agitator as a mechanochemical process for recycling WPCBs. The RGF separated in the WPCBs was applied as a reinforcement in the RGF/unsaturated polyester composites to reuse as a reinforcement.

• Journal of the Korean Ceramic Society
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• v.34 no.5
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• pp.491-499
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• 1997

High flexible lightweight composites containing tobermorite as a main mineral is produced using various amorphous silicates, lime, cement and fibers. Here, Mechanical properties of the composites were studied by observing microstructures of hydrates and fibers. Amorphous silicates having better hydraulicity retarded the crystallization of tobermorite due to better formation of C-S-H gel in water bath curing, but, difficult conversion from C-S-H gel to tobermorite in hydrothermal reaction. In the low molar ratio of CaO/SiO2 (0.67), faster crystalization was observed dued to more impurities such as Al2O3 alkali, resulting in improving mechanical properties due to small crystal size and many contact points. It was identified that a lot of calcium silicate hydates formed at surface of pulps increase bonding strength and the crack-resistance of matrix in the composites, but decrease hardness and compressive strength. The choice of amorpous silicates having better hydraulicity, low CaO/SiO2 adding each fibers bellow about 5% in the raw mixs and lower molding pressure should be needed at improve mechanical properties of composites.

• Journal of the Korean Graphic Arts Communication Society
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• v.30 no.3
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• pp.13-21
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• 2012

This study was carried out to evaluate the stability of archival documents produced using papers. The properties of archival documents depend on the type of fillers of papers that are used such as fiber, non cellulose fiber, and mineral. The physio-chemical characteristics of archival documents were analyzed by employing acid hydrolysis against cellulose fiber substances. Fibers of Korean hand-made (Hanji), flex, and cotten papers showed higher pH and the degree of polymerization (DP) than wood fiber and mechanical fiber. Mechanical pulp containing 12.8% of lignin showed the greatest decrease of DP due to acid hydrolysis, and this resulted in increase of degree of aging. The filler found to clay and talc did not contain metal such as $Fe^{+2}$, $Fe^{+3}$, and $Cu^{+2}$. The alkaline metals such as Mg, Ca, and Ti showed greater resistance to acid hydrolysis.

• International Journal of Industrial Entomology and Biomaterials
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• v.43 no.2
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• pp.52-58
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• 2021

The article presents the results of the content of the chemical and biochemical composition of the pupa of the wild silkworm Saturnia pyri belonging to the family Saturniidae, species of Lepidoptera. The nutritional value of silkworm Saturnia pyri pupae was evaluated, which contained 51% dry matter, 52.50% crude protein, 27.89% fat, 10.50% chitin fibers, 2.5% ash and 27 macro- and microelements and 25 mg alpha tocopherols in 100 g oil. The X-ray fluorescence method was used to determine the content of mineral elements in the pupa of the silkworm Saturnia pyri. It was revealed that the pupa of this type of silkworm contains 25 elements, of which the relative amount of K, Mg, Na, Ca, Al is much higher than other elements.

• International Journal of Highway Engineering
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• v.14 no.5
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• pp.21-29
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• 2012

PURPOSES: This study is to investigate the mechanical performance of the fiber reinforced lean concrete with respect to different types of fibers. METHODS: Increased vehicle weight and other causes from the exposed conditions have accelerated the deteriorations of road pavement. A new multi-functional composite pavement system is being developed recently in order to extend service life and upgrade the pavement. A variety of tests were conducted before and after hardening of the concrete. RESULTS: From the test results, it was found that the use of different types of fibers did not affect the compressive strength development. This might be due to the inherent property of the lean concrete. When steel fibers were used relatively greater flexural strength and flexural fracture toughness were developed. Also addition of fly ash by replacing a part of Portland cement the fracture toughness was slightly increased. CONCLUSIONS: It has been known that the addition of fibers and use of mineral admixture can be positively considered in the development of multi-functional composite pavement system as its required mechanical performance is obtained.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.159.2-159.2
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• 2010

Asbestos is the collective name for a group of naturally occurring minerals in their fibrous form and hydrous silicates of magnesium and a mineral fiber that has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Asbestos has been used for a wide range of manufactured goods, because of its fiber strength and heat resistant properties. Nevertheless harmful of asbestos is quite serious. Exposure to airborne friable asbestos may result in a potential health risk because persons breathing the air may breathe in asbestos fibers. Continued exposure can increase the amount of fibers that remain in the lung. Fibers embedded in lung tissue over time may cause serious lung diseases including asbestosis, lung cancer. In this paper, we carried out as fundamental study for dispose of asbestos cement slate safely and perfectly. Melting Temperature of asbestos need to more than $1,520^{\circ}C$ and specially asbestos cement slate need more energy than that of pure asbestos. We need to decrease melting temperature of asbestos cement slate for economical efficiency. To the purpose, glass and bottom ash were chosen as additives for basicity control. we analyzed about properties of asbestos cements slate, melting characteristics on the additives ratio and temperature. We confirmed about harmlessness of melting slag through analysis of scanning electron microscope(SEM) and x-ray diffractometer(XRD).

• Journal of the Korea Institute of Building Construction
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• v.11 no.4
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• pp.379-386
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• 2011

Durability of concrete is an important issue, and one of the most critical aspects affecting durability is chloride diffusivity. Factors such as water.cement ratio, degree of hydration, volume of the aggregates and their particle size distribution have a significant effect on chloride diffusivity in concrete. The use of polypropylene fibers(particularly very fine and well dispersed micro fibers) or mineral additives has been shown to cause a reduction in concrete's permeability. The main objective of this study is to evaluate the manner in which the inclusion of fiber(in terms of volume and size) and blast furnace slag(BFS) (in terms of volume replacement of cement) influence the chloride diffusivity in concrete by applying 3D computer modeling for the composite structure and performing a simulation of the chloride penetration. The modeled parameters, i.e. chloride diffusivity in concrete, are compared to the experimental data obtained in a parallel chloride migration test experiment with the same concrete mixtures. A good agreement of the same order is found between multi.scale microstructure model, and through this chloride diffusivity in concrete was predicted with results similar to those experimentally measured.

• Toxicological Research
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• v.22 no.3
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• pp.237-244
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• 2006

Two kinds of sepiolite, a $500^{\circ}C$ heat-treated sepiolite, and a $700^{\circ}C$ heat-treated sepiolite were analyzed for their physicochemical properties. After these sepiolites were instilled into rat lungs, the effects of the substances on lung pathological changes were evaluated. The lungs instilled with sepiolite increased their weight compared with the unexposed control. The pathological examination further showed increased legions of granuloma with early fibrosis. The heat treated sepiolites, however, did not show any toxicological differences from the untreated sepiolites. Thus chronic experiments are needed to evaluate the durability of mineral fibers, which is an essential experiment for evaluating biopersistence of fibers in lungs.