• Analytical Science and Technology
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• v.12 no.1
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• pp.13-21
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• 1999

Silicate used as laundry detergent builder was good for pH buffering capacity and solubility but calcium-ion binding capacity and surfactant adsorption ability were lower. As $SiO_2/Na_2O$ molar ratio became higher, pH buffering capacity and ion exchange ability were lower and surfactant adsorption ability was little higher. Anionic surfactant LAS (linear alkylbenzene sulphonate), nonionic surfactant LA-9 (lauryl alcohol EO-9) were used to investigate the detergency performance. Zeolite was better than sodium silicate in detergency performance. In case of LAS, detergency performance was good when $SiO_2/Na_2O$ molar ratio was lower. In case of LA-9, detergency performance was similar without discrimination of molar ratio of $SiO_2/Na_2O$.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.4
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• pp.365-373
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• 2007

We optimized the compositions of electrolyte and additives for anode in Ni-MH battery to improve the electrode characteristics at ambient and low temperatures using response surface method(RSM). Among various additives for anode, PTFE exhibited the greatest influence on the discharge capacity of the anode. Through response optimization process, we found the optimum composition of the additives to exhibit the greatest discharge capacity. When the amount of additives was too small, the anode was degraded with time due to the low binding strength among alloy powders and the resultant separation of powders from the current collector. In contrast, the addition of large amount of the additives increased in the resistance of the electrode. In addition, the discharge capacity of the anode at $-18^{\circ}C$ increased with decreasing the concentration of KOH, NaOH and LiOH in design range of electrolyte. The resistance and viscosity of electrolyte appear to affect the discharge capacity of the anode at low temperature.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.4
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• pp.75-82
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• 2015

In this study, experimental research was carried out to evaluate steel reinforced ECC (Engineered Cementitious Composites) column, which exhibits excellent crack control property and highly ductile behavior. Ordinary portland cement and high volume fly ash were used as binding materials in the mixture proportions for the purpose of achieving a high level of multiple cracking property with the tightly controlled crack width. To compare with the cyclic behavior of steel reinforced ECC column specimen, a conventional reinforced concrete column was prepared and tested under reversed cyclic loading condition. Based on the cyclic load test, ECC column exhibited higher cyclic behavior, compared to the conventional RC column, in terms of load carrying capacity and energy dissipation capacity.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.139-142
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• 2018

Silicon (Si) is a promising anode material for next-generation lithium ion batteries (LIBs) because of its high capacity of 4,200 mAh/g ($Li_{4.4}Si$ phase). However, the large volume expansion of Si during lithiation leads to electrical failure of electrode and rapid capacity decrease. Generally, a binder is homogeneously mixed with active materials to maintain electrical contact, so that Si needs a particular binding system due to its large volume expansion. Polyvinyl alcohol (PVA) is known to form a hydrogen bond with partially hydrolyzed silicon oxide layer on Si nanoparticles. However, the decrease of its cohesiveness followed by the repeated volume change of Si still remains unsolved. To overcome this problem, we have introduced the electrospinning method to weave active materials in a stable nanofibrous PVA structure, where stresses from the large volume change of Si can be contained. We have confirmed that the capacity retention of Si-based LIBs using electrospun PVA matrix is higher compared to the conservative method (only dissolving in the slurry); the $25^{th}$ cycle capacity retention ratio based on the $2^{nd}$ cycle was 37% for the electrode with electrospun PVA matrix, compared to 27% and 8% for the electrodes with PVdF and PVA binders.

• Korean Journal of Environmental Agriculture
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• v.24 no.4
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• pp.379-385
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• 2005

This study was conducted to find out a useful bioremediation technology for heavy metal contaminated soil and water. We isolated strain CPB from heavy metal contaminated soil and evaluated the tolerance level and adsorption capacity of strain CPB to heavy metals (Strain is not determined yet). Strain CPB showed variable tolerance limit to different kinds heavy metal or concentrations of heavy metals. The growth of strain CPB was significantly inhibited by mixed heavy metals (Cd+Cu+Pb+Zn) than that of by single heavy metal. Strain CPB showed high binding capacity with Pb (Pb>Cd>Cu>Zn). In general, strain CPB showed high uptake of heavy metals such as Pb, Cd and Cu. It was observed that the capacity of heavy metal uptake from mixture of heavy metals was reduced in comparison with single heavy metal treatment. But total contents of heavy metal bound with cell in mixed heavy metal showed higher than in single heavy metal treatment. Heavy metal adsorption in cells was affected by several external factors, such as temperature and pH etc.. The optimum temperature and pH of the adsorption of heavy metal into cells were ca. $25{\sim}35^{\circ}C$ and pH ca. $5{\sim}7$, respectively. A large number of the electron dense particles were found mainly on the cell wall and cell membrane fractions, which was determined by transmission electron microscope. Energy dispersive X-ray spectroscopy revealed that the electron dense particles were the heavy metal complexes the substances binding with heavy metals.

• Journal of the Korea Concrete Institute
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• v.28 no.2
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• pp.157-165
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• 2016

It is possible to achieve high strength ranging from 40 MPa to 70 MPa in alkali-activated slag concrete (AASC), and AASC is also known to have a finer pore structure due to its high latent hydraulicity and fineness of slag cement, which makes it difficult for chloride ions to penetrate. Electrophoresis is mostly used to calculate the effective diffusion coefficient of chloride ions, and then to evaluate resistance to salt damage. Few studies have been conducted on the fixation capacity of chloride ions in AASC. For this reason, in this study the chloride fixation within the hardened paste was evaluated according to the type and the amount of alkaline activators. As a result, it was revealed that among the test specimens, the chloride fixation was greatest in the paste containing $Na_2SiO_3$. In addition, it was found that as more activator was added, a higher level of chloride fixation was observed. Through this analysis, it can be concluded that the type and the amount of alkaline activators have a high correlation with the amount of C-S-H produced.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.683-689
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• 1994

With a view to utilizing effectively fish skin wastes from marine manufactory, a gelatin solution extracted from yellowfin sole skin was fractionated by precipitation with ethanol, and then the functional and physico-chemical properties for the fractionated gelatin were determined. Ethanol was added up to 50% of ethanol content to a gelatin solution extracted from yellowfin sole skin, then the mixture was left to stand at $0^{\circ}C$ for 12 hours. Finally, the precipitates were dried by hot-air ($40^{\circ}C$). The gel strength and melting point of a 10% gel of gelatin prepared from yellowfin sole skin by precipitation with ethanol has 322.4g and $23.3^{\circ}C$, respectively. The physico-chemical properties of the ethanol treated fish skin gelatin were superior to those of fish skin gelatin prepared without ethanol treatment. Besides, the functional properties of the ethanol treated gelatin were lower in solubility and higher in water holding capacity, oil binding capacity, emulsifying activity, emulsifying stability, foam expansion and foam stability than those of pork skin gelatin sold on market as well as gelatin prepared without ethanol treatment. It may be concluded, from these results, that the fish skin gelatin prepared by precipitation with ethanol can be effectively utilized as a human food by improving the functional properties.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.53-60
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• 1998

This study examines the effect of pH, temperature, metal ion concentration and culture density on metal biosorption by the nuisance cyanobacterium Microcystis aeruginosa. Ni biosorption was higher at pH 9.2 than at neutral and acidic pH. In contrast the biosorption of Cu and Zn was maximum at pH 7.0. However, biosorption of Zn was difficult to measure at pH values 9.2 and 10.5, owing to the formation of insoluble complexes. All the test metals (Cu, Zn, and Ni) showed maximum biosorption rate at low culture densities of 40 mg dry wt $1^{-1}$. The biosorption of Cu, Zn, and Ni was maximum at $40^{\circ}C$. However, no worthwhile difference in Zn and Ni sorption was noticed at 4 and $29^{\circ}C$ as compared to $40^{\circ}C$. Of these three metals used Microcystis showed a greater binding capacity ($K_{f}$ value=0.84, Freundlich adsorbent capacity) and accelerated biosorption rate for Cu under various environmental conditions. Fitness of mathematical models on metal biosorption by Microcystis confirmed that the biological materials behave in the same way as physical materials. These results suggest that before using a biosorbent for metal recovery, the environmental requirements of the biosorbent must be ascertained.

• Food Science of Animal Resources
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• v.32 no.6
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• pp.695-705
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• 2012

Dietary fiber naturally present in various sources of cereals, legumes, fruits and vegetables plays a physiological role in human health, such as lowering cholesterol and blood pressure, improving blood glucose control in diabetes, helping with weight loss and management, and reducing cancer risk. In addition, dietary fibers have has been added as a functional food ingredient to food products to provide water-holding capacity, viscosity, gel-forming ability, and fat-binding capacity to food products. These beneficial characteristics of dietary fiber components can improve the image of meat products to be healthy and functional food products. This article reviews the concept and current definition of dietary fibers in food products along with their health benefits and functional characteristics. Dietary fibers from different sources like cereals, legumes, fruits, and vegetables and soluble dietary fibers have been applied as functional ingredients to various types of meat products, such as beef patties, ground beef and pork, pork and chicken sausages, meatballs, and jerky etc. Based on the application of dietary fibers to different types of meat products, possible future characteristics in selecting appropriate dietary fiber ingredients and their proper incorporation are explored to develop and produce healthy and functional meat products with high dietary fiber contents.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1404-1410
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• 2009

Chestnut flours (CFs) were produced from 3 chestnut samples (Aydin, Kutahya, and Bursa) by 2 different methods (boiled and oven-dried: BOD-CF and freeze-dried: FD-CF). Functional properties and effects of CF addition (10, 20, and 30%) on the qualities of regular and low-fat cookie were investigated. The freeze drying significantly increased water solubility of CFs but decreased their water binding capacity. The emulsion capacity and stability of FD-CFs were higher than those of BOD-CFs. At pH 4, 6, 8, and 10 FD-CFs had better gelation properties. Spread ratio (SR) values of BOD-CF supplemented regular or low-fat cookies decreased with increasing CF levels. Hardness values of CF supplemented regular cookies were generally lower compared to control. SR and hardness values of FD-CF supplemented cookies were higher than those of BOD-CF supplemented ones. Surface colors of the cookies were darker with FD-CF addition as compared to BODCF addition. In low-fat cookies, the sample supplemented with 10% Kutahya FD-CF had the highest taste-flavor value. FDCF supplementation generally resulted in higher appearance and taste-flavor scores than BOD-CF supplementation in cookies.