• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.33-34
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• 2003

Lyocell yarns were treated with NaOH, liquid ammonia, high pressure steam and polycarboxylic acids, and dyed with five reactive dyes. The water content of the samples was also measured by the centrifugal and chromatographic techniques. The total pore volume w as substantially increased by NaOH treatment, while decreased by high pressure steaming. The pore size distributions for the dyed samples were affected by the dyes used.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.67-68
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• 2003

Native corn starch and montmorillonite caly nanocomposites were prepared using the glycerol as the plasticizer. These were characterized by mechanical analysis, X-ray diffraction, infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The tensile strength increased with the clay content to a maximum point and then decreased due to gapping between the two phases. Dispersion of the layered silicate within the starch was verified using X-ray diffraction pattern. Examination of these materials by scanning electron showed that intercalates have good wetting to the starch surface.

• Proceedings of the Korean Society of Crop Science Conference
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• 1991.10a
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• pp.24-25
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• 1991

• Economic and Environmental Geology
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• v.22 no.1
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• pp.21-34
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• 1989

Chindong granites are classified into granodiorite, tonalite and quartz-diorite, and Yucheon - Eonyang granites into monzo-granite by the Streckeisen diagram. These granitic rocks of Cretaceous age show trend of calc-alkaline magma, and the magmatic evolution from basic to acidic rocks is consistant with the general crystallization path of the Cretaceous granitic rocks in the Gyeongsang basin. On the basis of petrological and petrochemical data, variation of major elements (K, Na, Ca, Mg) and trace elements (Rb, Sr, Ba) including ore metals (Cu, Pb, Zn) in the Cretaceous granitic rocks were studied in detail in order to investigate geochemical difference of the granitic rocks in relation to mineralization between Cu province and Pb-Zn province in the Gyeongsang basin. There is clear difference in content of the major elements between Chindong granites and Yucheon-Eonyang granites : Chindong granites have low content of K (1.62%) and Na (2.53%), and high content of Ca (3.75%) and Mg (1.42%) whereas Yucheon-Eonyang granites have high content of K (3.56-3.60%), and low content of Ca (0.96-0.26%) and Mg (0.26-0.21%). There is also clear difference in content of trace lithophile elements between Chindong granites and Yucheon-Eonyang, granites : Chindong granites have low content of Rb (86ppm) and Ba (330ppm), and high content of Sr (405ppm) while Yucheon-Eonyang, granites have high content of Rb (144-161ppm) and Ba (983-1030ppm), and low content of Sr (157-136ppm). The lithophile trace elements of Rb and Sr vary with close relationship to major elements of K and Ca, respectively. Therefore, Chindong granites are much easily distinguished from Yucheon-Eonyang granites by using relationship of K with Rb and Ca with Sr : K<3%, Rb<100ppm, Ca<2% and Sr>200ppm for Chindong granites, and K>3%, Rb>100ppm, Ca<2%, and Sr<200ppm for Yucheon-Eonyang granites. There is not clear difference in content of trace ore metals between Chindong granites and Yucheon-Eonyang granites : Chindong granites of the Cu province have low Cu content (15ppm) which is nearly equal to 13-14ppm of Yucheon-Eonyang granites of the Pb-Zn province, and Yucheon-Eonyang granites have Pb content (29-27ppm) which is rather lower than 37ppm of Chindong granites. But Cu is anomalously high in the mineralized part of Chindong granites in Gunbuk-Haman area, and Zn is apparently higher in Yucheon-Eonyang granites (51-37ppm) than in Chindong granites (29ppm). K/Pb ratio is also c1early distinguishable between Chindong granites (<850) and Yucheon-Eonyang granites (>850). Thus, it may be possible to apply geochemical difference of the granites to distinguish whether a Cretaceous granitic body is Cu related rock or Pb-Zn related rock, and whether it belongs to Cu province or Pb-Zn province in the Gyeongsang basin.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.2
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• pp.89-93
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• 2005

To manufacture the low-salt anchovy, Engraulis japonicus, sauces with $14\%$ and $17\%$ NaCl, anchovy sauce with $26\%$ NaCl was diluted with sterilized water and then heated at $60^{\circ}C$ for 10 min, 20 min, 30 min, and 40 min. The chemical and microbial changes of the heat-treated low-salt anchovy sauces stored at $25^{\circ}C$ were analyzed at different storage periods. Lactic acid and total nitrogen contents of $14\%$ and $17\%$ NaCl anchovy sauces decreased slightly during storage, but pH, VBN and amino nitrogen contents were almost constant. The amino nitrogen content of $17\%$ NaCl anchovy sauce was higher than that of $14\%$ NaCl anchovy sauce. Total viable cell and lactic acid bacteria were not detected in the anchovy sauce heated at $60^{\circ}C$ for more than 20 min and only proteolytic bacteria was determined less than 10 CFU/mL. The 17% NaCl anchovy sauce heated at $60^{\circ}C$ for 30 min was relatively good for the taste and odor by sensory evaluation.

• Journal of Nutrition and Health
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• v.29 no.10
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• pp.1096-1104
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• 1996

This study was performed to evaluate the effect of sodium cholride supplementation on bone metabolism in female rats consuming a low calcium diet. Twenty five female rats were divided into three dietary groups (control Na : 0.1038%, 1% Na : 1.036%, 2% Na : 2.072%). All experimental diets contained 0.27% Ca and were fed to rats with deionized water for 7 weeks. Bone mineral density(BMD) and bone mineral content(BMC) of total body, spine and femur were measured using energy x-ray absorptiometry(DEXA) by small animal software. Then Ca efficiency was calculated from BMD and BMC. Serum Ca, P, Na and urine Ca, P, Na were determined. Urinary pyridinoline, serum ALP were measured to monitor bone resorption. Following 7 weeks, sodium cholride supplemented groups had higher urinary Ca excreteion, urinary pyridinoline, crosslinks value and serum ALP. There was no significant difference in case of serum Ca among all groups. Sodium chloride supplemnted groups had lower Ca effciency of total, spine and femur BMD and BMC than that of control group. In conclusion high salt intake not only increases urinary Ca excretion as urinary Na excretion does but also increase bone resorption and decrease Ca efficiency of each bone. It is been suggested that high salt intake may be harmful for bone maintenance. Therfore, the decrease of salt intake to the level of recommendation would be desirable.

• Korean Journal of Crystallography
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• v.12 no.2
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• pp.97-101
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• 2001

Phillipsite-type zeolite powders were synthesized from domestic coal fly ash by hydrothermal reaction with 2.0 M-3.5M NaOH solution at $80^{\circ}C{\sim}120^{\circ}C$ for 24 h. The properties of zeolite were investigated by XRD, SEM and IR spectroscopy. The effects of chemical composition of fly ash, reaction temperature and NaOH concentration on the zeolite synthesis were well appeared on IR spectra. It is found that the $TO_4$(T=Si, Al) tetrahedra have a well ordered structure as the $SiO_2$ content, synthesis temperature and NaOH concentration become high.

• Journal of Electrochemical Science and Technology
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• v.12 no.4
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• pp.398-405
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• 2021

To fabricate a full-scale pilot model of the cost-effective Na-(Ni,Fe)Cl₂ cell, a Na-beta-alumina solid electrolyte (BASE) was developed by applying a one-step synthesis cum sintering process as an alternative to the conventional solid-state reaction process. Also, Fe metal powder, which is cheaper than Ni, was mixed with Ni metal powder, and was used for cathode material to reduce the cost of raw material. As a result, we then developed a prototype Na-(Ni,Fe)Cl₂ cell. Consequently, the Ni content in the Na-(Ni,Fe)Cl₂ cell is decreased to approximately (20 to 50) wt.%. The #1 prototype cell (dimensions: 34 mm × 34 mm × 235 mm) showed a cell capacity of 15.9 Ah, and 160.3 mAh g^-1 (per the Ni-Fe composite), while the #2 prototype cell (dimensions: 50 mm × 50 mm × 335 mm) showed a cell capacity of 49.4 Ah, and 153.2 mAh g^-1 at the 2^nd cycle.

• Current Photovoltaic Research
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• v.2 no.1
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• pp.28-35
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• 2014

High-efficiency in $Cu(In,Ga)Se_2$ (CIGS) solar cells were usually achieved on soda-lime glass substrates due to Na incorporation that reduces deep-level defects. However, this supply of sodium from sodalime glass to CIGS through Mo back electrode could be limited at low deposition temperature. Na content could be more precisely controlled by supplying Na from known amount of an outside source. For the purpose, an $Na_2S$ layer was deposited on Mo electrode prior to CIGS film deposition and supplied to CIGS during CIGS film. With the $Na_2S$ underlayer a more uniform component distribution was possible at $350^{\circ}C$ and efficiency was improved compared to the cell without $Na_2S$ layer. With more precise control of bulk and surface component profile, CIGS film can be deposited at low temperature and could be useful for flexible CIGS solar cells.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.3
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• pp.166-171
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• 2003

This study was conducted to investigate the negative physiological impact of saline to roadside trees and to assess the physio-biochemical tolerant characters of woody plants against salinity. Two-year-old Zelkova serrata seedlings treated with 0, 3, 14, 56, and 112 mM NaCl were measured for root collar diameter and cambial electric resistance (as an indication of vitality) and analyzed for carbohydrate and mineral content in the leaves. Z. serrata was affected by NaCl treatments. The vitality of Z. serrata decreased with an increase in NaCl concentration, and the NaCl treatment resulted in nutrient imbalance shown by changes of ion concentration in the tissues. However, relative growth rate for diameter and carbohydrate metabolism in the leaves were not greatly influenced by NaCl treatment. Short-term treatment or low NaCl concentration may not have an observed impact on growth. Nevertheless, roadside trees exposed to saline during the long term would likely show negative effects for growth performance from altered ion concentrations.