• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.481-486
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• 1995

The salt stress at seedling stage of winter barley was examined in different concentrations of NaCl containing 1/2 Hoagland solution. Fresh weight of seedling at 30 days after seeding was highest at 25mM of NaCl concentration containing 1/2 Hoagland solution but if the NaCl concentration was more than 50mM it began to decrease seriously. Water content in plant was decreased according to increase of NaCl concentration in 1/2 Hoagland solution, so physiological mechanism of NaCl in barley was different from saline plant. Stoma number per cm$^2$ of first leaf was higher than that of control in case of stressed by NaCl but in that case the leaf length was decreased so the number of stoma per first leaf was slightly decreased. Chloroplast shape was not changed by 75mM of high NaCl contained 1/2 Hoagland solution but cell division at root growing point was inhibited by 75mM of NaCl. As the result of salt stress mitochondria was ruined in structure and irregular solid was found to be transfered from the cytoplasm to the cell wall in root growing point.

• Journal of the Korean Ceramic Society
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• v.28 no.8
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• pp.626-634
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• 1991

The specimens for the corrosion test were made by hot-pressing of SiC power with 2 wt% Nl2O3 and 10wt% Al2O3 additions at 200$0^{\circ}C$ and 205$0^{\circ}C$. The specimens were corroded in 37 mole% NaCl and 63 mole% Na2SO4 salt mixture at 100$0^{\circ}C$ up to 60 min. SiO2 layer was formed on SiC and then this oxide layer was dissolved by Na2O ion in the salt mixture. The rate of corrosion of the specimen containing 10 wt% Al2O3 was slower than that of the specimen containing 2 wt% Al2O3. This is due to the presence of continuous grain boundary phase in the specimen containing 10 wt% Al2O3. The oxidation of SiC produced gas bubbles at the SiC-SiO2 interface. The rate of corrosion follows a linear rate law up to 50 min. and then was accelerated. This acceleration is due to the disruption oxide layer by the gas evolution at SiC-SiO2 interface. Pitting corrosion has found at open pores and grain boundaries.

• The International Journal of Costume Culture
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• v.4 no.2
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• pp.86-93
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• 2001

Agricultural drainage salt generated during irrigation of crops in San Joaquin Valley, California exceeds 600,000 tons annually and cumulates in the field in a rapid rate. As a result, the waste is taking out more farmlands for salt storage and disposal, imposing serious concerns to environment and local agricultural industry. in searching for a potential solution to reduce or eliminate the waste, this research explored feasibility of producing a value-added product, sodium sulfate, from the waste and utilizing the product in textile dyeing. The result indicated that sodium sulfate could be produced the salt and could be purified by a recrystalization method in a temperature range within the highest and lowest daily temperatures in summer in the valley. Re recovered sodium sulfate samples, with purifies ranging from 67% to 99.91, were compard with commercially available sodium sulfate in directive dyeing of cotton fabrics. Direct Yellow 27 and direct Blue 1 had similar exhaustions among Na₂So₄Ⅰ, Na₂So₄Ⅱ, Na₂So₄Ⅲ and V which had similar ratios of sodium sulfate and sodium chloride in recovered salts. Na₂So₄Ⅳ had high exhaustion despite low ratios of sodium sulfate and sodium chloride. In direct Red 80, exhaustion depends more on the ratios of sodium sulfate and sodium chloride than sodium chloride. Na₂SO₄Ⅳ and Na₂SO₄V with high ratios of sodium chloride had more exhaustion than Na₂So₄and Na₂So₄Ⅲ with low ratios of sodium chloride. Generally, directive dyeing using recovered salts from farm drainage has similar or more excellent exhaustion than directive dyeing using commercial sodium sulfate.

• Journal of the Korean Ceramic Society
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• v.31 no.9
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• pp.957-968
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• 1994

Manufacturing process of porous glass by the filler method was studied. Commercial soda-lime-silicate glass powder was mixed with inorganic salt as the filler such as KCl, K2SO4, Na2SO4. Sintering shrinkages of mixed powders with the variation of sintering temperature were compared, and the effects of the fillers to shrinkages of mixed powder were increased in the order of Na2SO4${\mu}{\textrm}{m}$ of pore diameter were manufactured when the filler sizes 100~200 ${\mu}{\textrm}{m}$. The open pore volume of porous glass is determined by the quantity of filler and porous glasses having open pore volume between 30 and 70 vol% are available. Available sintering temperature range for preparation of porous glass is from the softening temperature of the glass powder to eutectic melting temperature of DTA curve of mixed powder.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.603-608
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• 2015

Alumina powder have been expanded its application in industry and required to control its morphology such as powder size and aspect ratio of single particle. It can be synthesized by molten - salt method which is possible to obtain various shapes of ceramic particles by controlling the growth direction because each crystal face has different growth rate. In this study, various combinations of salts such as NaCl, $Na_2SO_4$, $Na_3PO_4$ and their mixture were used for control the growth of plate like alumina particle from the initial stage of synthesis because salt having different ionic strength can control the growth direction of ceramic particle under its melting condition around $800{\sim}900^{\circ}C$, and growth behavior of plate-like alumina particle with different reaction conditions such as temperature and concentration on the crystal size and shape was studied.

• Resources Recycling
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• v.30 no.1
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• pp.35-43
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• 2021

In this study, Na2SO4 and KCl reagents were used to synthesize K2SO4 as a basic study for recycling byproducts generated during the manufacture of steel and cement. The mole ratio of Na2SO4 to KCl, the saturation of the solution, and the stirring temperature were controlled to derive the optimal manufacturing conditions. The microstructure and crystallinity of the materials prepared were evaluated using scanning electron microscopy and X-ray diffraction analysis. Pure K2SO4 was obtained when the mole ratio of Na2SO4 to KCl was 1:6-18, the saturation of the solution was less than 160%, and the stirring temperature was 20℃, 50℃. The optimal manufacturing conditions to maximize the crystallinity and yield of K2SO4 while minimizing the energy consumption were 1:6 mole ratio of Na2SO4 to KCl, 140% saturation of the solution, and 20℃ stirring temperature.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.2
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• pp.83-90
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• 2006

The NaCl contents of food waste composts made by various techniques known up to now were under the level of 1% by fresh weight basis. But these techniques has some problem that is environment pollution from treated water and high equipment cost. The application to agricultural land of food waste compost that is not sufficiently removed NaCl was considered to be improper due to salt accumulation in soils and plant growth inhibition by salt stress. The purpose of this study is to decompose NaCl in food waste compost using triple salt and this method is differ from existing chemical method. Also, reaction of NaCl with triple salt produced KCl that is basic material of potassium fertilizer. Moreover Also, there was temperature rise of average $5^{\circ}C$ as result that apply triple salt in food waste 600 ton in food wast composting productive capacity. Obvious odious smell reduction effect appeared pretreatment process and fermentation process with temperature rise and this is because triple salt activation of aerobe and removes odious smell cause material by salt content decrease effectively.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.112-115
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• 2001

Salt accumulation and movement by runoff ware studied in runoff resevior lysimeter constructed in a green house located in the area of Cheongju, Chungbuk province. Average runoff ratio of rainfall within period of this experiment was 58%. The average content of cations lost from field soil by runoff was in the order of $Ca^{2+}(27.12\;mg/L\;)$ > $K^+(9.18\;mg/L)$ > $Mg^{2+}(2.53\;mg/L)$ > $Na^+(1.89\;mg/L)$ and in the care anions $SO_4\;^{2-}(63.38\;mg\;/L)$ > $NO_3\;^-(25.40\;mg/L)$ > $Cl^-(4.19\;mg/L)$ > $PO_4\;^{3-}(3.18\;mg/L)$. Amounts of salt movement by runoff $SO_4\;^{2-}(140.2\;kg/ha)$, $Ca^{2+}(59.9\;kg/ha)$, $NO_3\;^-(56.1\;kg/ha)$, $K^+(20.3\;kg/ha)$, $Cl^-(9.3\;kg/ha)$, $PO_4\;^{3-}(7.0\;kg/ha)$, $Mg^{2+}(5.6\;kg/ha)$ and $Na^+(4.2\;kg/ha)$. The loss amount of $PO_4\;^{3-}$ was the lowest among the anions investigated in this experiment. $P_2O_5$ was accumulated on the soil surface due to strong affinity for the sorption site on the soil particle surface.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1048-1054
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• 2014

The purpose of this study was carried out to investigate the cause of sulfur dioxide occurrence, general element composition, sulfur compounds, heavy metals, macro- & micro-minerals, and oxidation-reduction potential (ORP) following baking time course of RS (RS1, RS2, RS3, and RS4) and mudflat solar salts (MSS). Sulfur dioxide ($SO_2$) and sulfite ($SO{_3}^{2-}$) were not detected in MSS or RS. However, sulfate ($SO{_4}^{2-}$) content significantly decreased in RS (29,878.15~36,097.45 ppm) compared to that in MSS (35,601.65 ppm). ORP was 181.15 mV in MSS, and 58.55 mV in RS1. Moisture content was 9.34% in MSS and 0.00% in RS with increased NaCl (94.77~95.77%). Moisture and NaCl contents showed no significant difference in RS. Insoluble and sandy residues were higher in RS than in MSS, whereas Ca and K showed no significant difference. Mg and Cl contents were higher in RS than in MSS. Br level was higher in MSS (628.1 ppm) than in RS (512.72~586.62 ppm), but there was no significant difference in $NO_3$. Heavy metals (Pb, As, and Hg) were more abundant in RS than in MSS, but levels were still safe. These results suggest that MSS and RS may increase protection against from $SO_2$ and $SO{_3}^{2-}$.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1742-1752
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• 2013

A basal diet (0.8 g/kg dNa) was formulated in which each of the two sources ($NaHCO_3$ and $Na_2SO_4$) were supplemented in such a way to attain four levels (1.7, 2.6, 3.5, and 4.4 g/kg) of total dNa, respectively, under $4{\times}2$ factorial arrangement. Eight dietary treatments were replicated four times, with 40 birds in each replicate (n = 1,280). The diets supplemented with $Na_2SO_4$ to attain higher levels of dNa showed highest BW gain and feed intake (FI) during d 1 to 10 (interaction effects) while 2.6 g/kg dNa exhibited improved BW gain and gain:feed (FG) during d 11 to 20. Linear rise in daily water intake (DWI) was associated with diets containing increasing dNa during d 1 to 42 ($p{\leq}0.036$). During the first 10 d, DWI:FI was found highest in $NaHCO_3$ diets while $Na_2SO_4$ diets showed highest DWI:FI during last 10 d of the experiment ($p{\leq}0.036$). Increasing dNa and changing $Na_2SO_4$ with $NaHCO_3$ salt increased pH and resulted in poor growth performance. Dressing weight ($p{\leq}0.001$) and abdominal fat ($p{\leq}0.001$; quadratic effect) were reduced, whereas breast ($p{\leq}0.001$) and thigh (p<0.001) weights were aggravated with increasing dNa (linear effects). Present findings suggested higher levels of dNa from $Na_2SO_4$ as the supplemental salt in broiler diets would produce better growth performance, especially in first ten days of life, and improve carcass and body organ characteristics.