• International Journal of Concrete Structures and Materials
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• v.9 no.3
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• pp.381-390
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• 2015

Investigating the microstructure of hardened cement mixtures with the aid of advanced technology will help the concrete industry to develop appropriate binders for durable building materials. In this paper, morphological, mineralogical and thermogravimetric analyses of autoclave-cured mixtures incorporating ground dune sand and ground granulated blast furnace slag as partial cementing materials were investigated. The microstructure analyses of hydrated products were conducted using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), differential thermal analysis (DTA), thermo-graphic analysis (TGA) and X-ray diffraction (XRD). The SEM and EDX results demonstrated the formation of thin plate-like calcium silicate hydrate plates and a compacted microstructure. The DTA and TGA analyses revealed that the calcium hydroxide generated from the hydration binder materials was consumed during the secondary pozzolanic reaction. Residual crystalline silica was observed from the XRD analysis of all of the blended mixtures, indicating the presence of excess silica. A good correlation was observed between the compressive strength of the blended mixtures and the CaO/$SiO_2$ ratio of the binder materials.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.244-248
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• 1999

Soondae was prepared with porcine plasma or egg white as a substitute of porcine blood and their nutritional value was evaluated for th purpose of improving the quality of Soondae. The total energy of Soondae was 181.9 kcal/100 g with the composition of 66.14% moisture, 9.25% protein. 10.44% fat, 0.89% ash, 0.54% fiber, and 12.74% carbohydrate. As the percentage of porcine plasma increased, the total energy was decreased. For the minerals, Fe content was the highest in original Soondae (8.5 mg/100 g) and the contents of Fe, Na, K were decreased with the increase of porcine plasma or egg white. The glutamic acid, leucine, lysine, glycine, and alanine were the major portion of the amino acid contents in Soondae. The U/S ratio was increased with the proportion of porcine plasma and egg white. The cholesterol content of original Soondae (66.6 mg/100 g) was decreased by 25.73% in porcine plasma Soondae and by 36.98% in egg white Soondae.

• Membrane and Water Treatment
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• v.11 no.1
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• pp.69-77
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• 2020

Former studies revealed that sepiolite thermally treated at high temperature have high adsorption capacity for phosphate. However, its micron size (75 ㎛) limits its application to water treatment. In this study, we synthesized sepiolite impregnated polysulfone (PSf) beads to separate it easily from an aqueous solution. PSf beads with different sepiolite ratios were synthesized and their efficiencies were compared. The PSf beads with 30% impregnated sepiolite (30SPL-PSf bead) possessed the optimum sepiolite ratio for phosphate removal. Kinetic, equilibrium, and thermodynamic adsorption experiments were performed using the 30SPL-PSf bead. Equilibrium adsorption was achieved in 24 h, and the pseudo-first-order model was suitable for describing the phosphate adsorption at different reaction times. The Langmuir model was appropriate for describing the phosphate adsorption onto the 30SPL-PSf bead, and the maximum adsorption capacity of the 30SPL-PSf bead obtained from the model was 24.48 mg-PO₄/g. Enthalpy and entropy increased during the phosphate adsorption onto the 30SPL-PSf bead, and Gibb's free energy at 35 ℃ was negative. An increase in the solution pH from 3 to 11 induced a decrease in the phosphate adsorption amount from 27.30 mg-PO₄/g to 21.54 mg-PO₄/g. The competitive anion influenced the phosphate adsorption onto the 30SPL-PSf bead was in the order of NO₃^- > SO₄^2- > HCO_3^-. The phosphate breakthrough from the column packed with the 30SPL-PSf bead began after ~2000 min, reaching the influent concentration after ~8000 min. The adsorption amounts per unit mass of 30SPL-PSf and removal efficiency were 0.775 mg-PO₄/g and 61.6%, respectively. This study demonstrates the adequate performance of 30SPL-PSf beads as a filter for phosphate removal from aqueous solutions.

• Journal of Advanced Navigation Technology
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• v.15 no.2
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• pp.298-306
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• 2011

In this paper, the RUNCODE encoder hardware IP was designed and implemented for symbol ID code length encoding, which is one of major modules of JBIG2 encoder for FAX. ImpulseC Codeveloper and Xilinx ISE/EDK program are used for the hardware generation and synthesis of VHDL code. The synthesized hardware was downloaded to Virtex-4 FX60 FPGA on ML410 development board. The synthesized hardware utilizes 13% of total slice of FPGA. Using Active-HDL tool, the hardware was verified showing normal operation. Compared with the software operating using Microblaze cpu on ML410 board, the synthesized hardware was better in operation time. The improvement ratio of operation time between the synthesized hardware and software showed about 40 times faster than software only operation. The synthesized H/W and S/W module cooperated to succeed in compressing the CCITT standard document.

• Journal of the Korean Ceramic Society
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• v.39 no.12
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• pp.1133-1137
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• 2002

The cement for solidification of the toxic waste was fabricated using a mixture of the waste concrete powder and blast furnace slag in the ratio of 1:1 and its hydrate morphology and compressive strength of the sample were evaluated in order to apply to the solidification of the COREX sludge. The X-ray diffraction analysis of the sample which prepared by the addition of 10% Portland cement and hemihydrate showed the presence of $Ca(OH)_2$, ettringite, gel-phase and C-S-H hydrate. Compressive strength of the sample exhibited enough high to use as a solidification cement. The strength of the sample was over 140 kgf/$m^2$ in 7 days in case of solidification of the COREX sludge and the sample possess sufficient morphology for the solidification and stabilization of the waste sludge.

• Macromolecular Research
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• v.12 no.4
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• pp.422-426
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• 2004

Solid polymer electrolytes based on poly(ethylene glycol)-polyurethane (PEG-PU) complexed with LiClO$_4$ salt have been prepared by the solvent casting method. A PEG-PU material (PEG:4,4'-diphenylmethane diisocyanate: l,4-butanediol = 1:2:1) was synthesized through a typical two-step condensation reaction. We investigated the effects of the salt concentration on the ionic conductivity ($\sigma$) and the glass transition temperature (T$_{g}$ ) of the complex electrolytes by using alternating current impedance spectroscopy, differential scanning calorimetry, and dynamic mechanical thermal analysis. The measured values of both $\sigma$ and T$_{g}$ exhibited similar tendencies in that they had maxima within the range studied, probably because of two opposite effects, i.e., the increased number of carrier ions and the decreased chain mobility (or increased T$_{g}$ ) caused by the increase in the salt concentration. The highest conductivity, on the order of 2.43 ${\times}$ 10$^{6}$ S$cm^{-1}$ /, was obtained at an [O]/[Li$^{+}$] ratio of ca. 16 (0.92 ㏖ salt per kg of matrix polymer).

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.723-738
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• 2014

This study examined nutrient intake of long-lived men and women living in Jeollanam-do (Gangjin, Goksung, Gurye, Damyang, Boseong, Suncheon, Jangheung) which is known as representative Korean longevity area. Using the 24 hr recall method, dietary nutrient intake data were collected from 134 subjects (67 for 80~89 years old, 67 for more than 90 years old) in spring and fall 2012. Nutrient for each subject were calculated using CAN-pro. Subjects' daily mean intake levels of macronutrients, vitamins and minerals were higher in fall than in spring. Compared to KDRIs, subjects less than recommend (RNI/AI). East consumed nutrients compared to KDRIs were folate, potassium, calcium, vitamin $B_1$, vitamin $B_2$ and vitamin E. Subjects 232.8~363.1% of recommended intake level for natrium. The nutrient adequacy ratio (NAR) was 0.87 for subjects in their 80s and 0.79 for than 90 years old. The average NAR of all subjects was 0.83. The index of nutritional quality (INQ) exceeded 1 for most nutrients except for Ca (0.87), K (0.77), vitamin $B_1$ (0.84), vitamin $B_2$ (0.70) and folate (0.68). The average INQ was 1.31. This study concluded that even though long-lived men and women living in Jeollanam-do consumed less than RNIs, nutrition consumption quality was relatively fine based on NAR and INQ results.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.5
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• pp.500-511
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• 2017

This study was conducted to investigate the anthropometric data, bone density, serum profiles, nutrient intakes and diet quality of premenopausal and postmenopausal women. For the study, we obtained data for analysis from the combined 2008~2011 Korean National Health and Nutrition Examination Survey (KNHANES). The height and weight were 157.8 cm and 58.7 kg in premenopausal women and 155.5 cm and 58.3 kg in postmenopausal women, respectively. The obesity rate was 27.49% in premenopausal women and 34.98% in postmenopausal women (p<0.001). Total cholesterol, LDL-cholesterol, triglyceride, GOT, GPT and alkaline phosphatase in postmenopausal women were significantly higher than those in premenopausal women (p<0.001). The prevalence of osteoporosis was 0.0~0.89% in premenopausal women and 0.48~13.22% in postmenopausal women (p<0.001). In postmenopausal women, rates of hypertension, stroke, myocardial infarction, depression, and diabetes were significantly higher than those in premenopausal women. Water, fat. ash, sodium, retinol, thiamin, riboflavin and niacin intakes in premenopausal women were significantly higher than those in postmenopausal women. Water, fiber, Ca, and, K intakes were below KDRIs (Dietary Reference Intakes for Koreans) in both groups. The mean adequacy ratio (MAR) of premenopausal women was higher than that of postmenopausal women (p<0.001). The index of nutritional quality (INQ) in premenopausal women was also higher than that of postmenopausal women except iron and vitamin C. Therefore dietary guidelines and an education program should be developed for desirable improvement of health, bone density, nutrient status and dietary quality of postmenopausal women.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2251-2255
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• 2013

Second-order rate constants ($k_{HOO^-}$) for the nucleophilic substitution reactions of Y-substituted-phenyl diphenylphosphinates (4a-4i) with $HOO^-$ in $H_2O$ have been measured spectrophotometrically. The ${\alpha}$-nucleophile $HOO^-$ is 10-70 times more reactive than the reference nucleophile $OH^-$ although the former is ca. $4pK_a$ units less basic than the latter, indicating the ${\alpha}$-effect is operative. The Bronsted-type plot for the reactions of 4a-4i with $HOO^-$ is linear with ${\beta}_{lg}=-0.51$, a typical ${\beta}_{lg}$ value for reactions which were reported to proceed through a concerted mechanism. The Yukawa-Tsuno plot is also linear with ${\rho}=1.40$ and r = 0.47, indicating that a negative charge develops partially on the O atom of the leaving group, which can be delocalized to the substituent Y through resonance interactions. Thus, the reactions have been proposed to proceed through a concerted mechanism. The magnitude of the ${\alpha}$-effect (i.e., the $k_{HOO^-}/k_{HO^-}$ ratio) decreases linearly as the leaving-group basicity increases. It has been concluded that solvation effect is not solely responsible for the ${\alpha}$-effect found in this study but the transition-state stabilization through an intramolecular H-bonding interaction is also responsible for the ${\alpha}$-effect.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.245-251
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• 1988

Thermolysin was immobilized on Dowex MWA-1 with 10% glutaraldehyde and incorpo rated into a fluidized-bed continuous coagulation scheme to make Cheddar type cheese. The activity yield of thermolysin was 25%. The immobillized thermolysin was stable at $60^{\circ}C$ in the presence of 1/200M calcium ions and the half-life value is 16 days at the temperature. Raw milk alkalified to pH 7.0 was passed through a column of thermolysin beads at $55^{\circ}C$, cultivated with Streptococcus cremoris and allowed to coagulate. A typical milk curd was formed to make Cheddar type cheese, avoiding troublesome microbial contamination successfully during continuous hydrolysis process. During ripening of this cheese for 6 months at $10^{\circ}C$, its ripening ratio and taste were similar to those of cheese prepared by the traditional method.