• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.105-109
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• 1987

The mineral content of Dolowe, which were prepared in the laboratory and marketed Korean products of Dolwoe, Japanese product of Dolwoe and Korean-roasted products of Dolwoe were analysed and compared. Dolwoe-leaf tea had high mineral content of Ca, Mg, Mn and Cu, while Dolwone-stem tea had high mineral content of K, Na and Fe. Especially in the ash of Dolwoe-stem tea showed the highest mineral content of K (33.4%) Dolwoe teas were extracted for 5 minutes as ratio of $1,000m{\ell}$ boiling water to 4g Dolwoe tea (250: 1, v/w). Comparing the ratio of extraction of minerals in Dolwoe tea made by us and marketed Dolwoe products, K was the most abundant element of all extractions with the rate of $83.2%{\sim}96.3%$ followed by Mg with $44.8%{\sim}62.2%$, Ca with $23.1%{\sim}64.4%$ and Na with $6.3%{\sim}55.6%$. On the other hand Mn, Fe and Cu were extracted in extremely small quantities.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.19-22
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• 1988

For decreasing the level of fluoride content in Antarctic krill, the changes of the content in solubel protein from the krill muscle depended on pH, ion species and ionic strength of the extracting solutions were investigated. The content of total fluoride of boiled muscle was higher than that of raw material, and the portions of fluoride with ionic form to the total content were 70% and 49%, respectively. In the effect of pH, fluoride contents of soluble protein from raw and boiled muscle showed the lowest values near 10. The effective ionic strength for decrease of fluoride content was 0.05M as NaCl at pH 11, and the content in the protein from raw material in this conditions was about 8 ppm.

• Journal of Ginseng Research
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• v.23 no.2 s.54
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• pp.61-66
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• 1999

Experiments were carried out to examine the rusty tolerance in 61 inbred lines of ginseng cultivated in field, and chemical components were analyzed to clarify the difference between healthy and rusty ginseng roots. Among them, 10 lines showed rusty tolerance (RT) while 10 lines showed rusty sensitivity (RS). The content of phenolic compound in RT was lower than that in RS in cortex, epidermis and branch & fine roots, but it was not difference between RT and RS in stele. The contents of K, Ca, Na in RT were lower than RS in cortex, and the content of Mg, Fe, Na, Mn, AI, Si in RT were lower than RS in epidermis, and the content of Fe in RT were lower than RS in branch & fine roots, but mineral contents were not difference between RT and RS in stele. The content of phenolic compound in healthy cortex was lower than that in rusty cortex in same 6-year roots, but the mineral contents were not difference between healthy and rusty cortex in same 6-year roots. In root of seedlings, the contents of phenolic compound, K and Na in RT were lower than RS. It was suggested that the contents of phenolic compound, K and Na might be marker to select rusty tolerance ginseng lines.

• Carbon letters
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• v.24
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• pp.62-72
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• 2017

The aim of this work was to evaluate the dielectric properties of impregnated and activated palm kernel shells (PKSs) samples using two activating agents, potassium carbonate ($K_2CO_3$) and sodium hydroxide (NaOH), at three impregnation ratios. The materials were characterized by moisture content, carbon content, ash content, thermal profile and functional groups. The dielectric properties were examined using an open-ended coaxial probe method at various microwave frequencies (1-6 GHz) and temperatures (25, 35, and $45^{\circ}C$). The results show that the dielectric properties varied with frequency, temperature, moisture content, carbon content and mass ratio of the ionic solids. PKSK1.75 (PKS impregnated with $K_2CO_3$ at a mass ratio of 1.75) and PKSN1.5 (PKS impregnated with NaOH at a mass ratio of 1.5) exhibited a high loss tangent ($tan{\delta}$) indicating the effectiveness of these materials to be heated by microwaves. $K_2CO_3$ and NaOH can act as a microwave absorber to enhance the efficiency of microwave heating for low loss PKSs. Materials with a high moisture content exhibit a high loss tangent but low penetration depth. The interplay of multiple operating frequencies is suggested to promote better microwave heating by considering the changes in the materials characteristics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.475-481
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• 2000

The growth of the microalgal Spiulina platensis in a batch photobioreactor had been studied to determine the influence of temperature, light intensity, and culture medium on the growth and c-phycocyanin content of the biomass. The most favorable conditions for high biomass and c-phycocyanin production were as follows: light intensity of 3500 lux, temperature of $35^{\circ}C,\;NaHCO_3\;of\;1.0{\%}$ for pH control, $0.2{\~}0.3{\%}\;Na_2CO_3$ for carbon source, and $0.2{\~}0.3{\%}\;NaCO_3$ for nitrogen source. The c-phycocyanin and chlorophyll content on most favorable condition were about $11{\%},\;1.0{\%}$, respectively.

• Korean Journal of Pharmacognosy
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• v.13 no.3
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• pp.102-105
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• 1982

Nine trace elements in Bear Galls(Fel Ursi) studied in this paper are Na, Mg, K, Ca, Cu, Zn, Fe, Pb and Ge. The contents of Na, Mg, K, Ca, Cu, Zn, Fe, Pb are determined by atomic absorption spectrometry and Ge is determined by graphite atomic absorption spectrometry. In both methods, the sample is digested with nitric-perchloric acid and then ashed. The results of analysis are shown in table and the result obtained from this study are as follows. a. The highest content of trace element of Bear Gall is Na and other elements are getting lower in order of K, Mg, Ca, Ge, Zn, Fe, Cu, and Pb. b. Particularly the content of Ge in Bear Gall was determined.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.91-92
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• 2007

An anomalous positive temperature coefficient of electrical resistivity (PTCR) was investigated in a ferroelectric lead-free perovskite-type compound $(Bi_{0.5}Na_{0.5})TiO_3$ within $BaTiO_3$-based solid solution ceramics. The effect of $Nb_2O_5$ content on the electrical properties and the microstructure of (1 - x) $BaTiO_3-x\;(Bi_{0.5}Na_{0.5})TiO_3$ (BNT) ceramics made using a conventional mixed oxide process also has been studied. The Curie temperature was obviously increased with the increasing of $(Bi_{0.5}Na_{0.5})TIO_3$ content. The Nb - doped BNT ceramics (x=0.01) display low resistivity values of $10^{1{\circ}}C-10^{2{\circ}}C$ ohm.cm at room temperature and the Curie Temperature of $T_c=160^{\circ}C$.

• Journal of the Korean Society of Food Culture
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• v.8 no.1
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• pp.73-77
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• 1993

We obtained the following results from determination of the sodium and potassium content contained in Denjang made in Korea and Japan. The mean sodium content of commercial denjang and home made denjang made in Korea and those of Japan are 4181.3 mg/100g, 6015.6 mg/100g and 5082.5 mg/100g, 5890.6 mg/100g, respectively. The mean potassium content of commercial denjang and home made denjang made in Korea and those of Japan are 595.8 mg/100g, 331.3 mg/100g and 365.4 mg/100g, 381.3 mg/100g, respectively. The mean NaCl concentration of commercial denjang and home made denjang made in Korea and those of Japan are 10.62%, 15.28% and 12.91%, 14.96% respectively. The mean Na/K ratios of commercial denjang and home made denjang made in Korea and those of Japan are 7.25, 21.54 and 14.42, 16.14 respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.413-418
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• 1998

There are several types of salts that classifed into raw salts(Chunil salt, Saeng salt), purified salts (NaCl reagent grade, Hanju salt) and processed salts(Gueun salt, Saeng kum, Bamboo salt) in Korea. Their major element is NaCl but raw salt from sea water contains other minerals such as K, Mg and S. Mineral contents of the various kinds of salt analyzed with ICP-AES and AAS were different, especially on the contents of K, Mg and Ca. Chunil salt was abundant in Ca(1,037ppm), K(3,707ppm), Mg(10,266ppm) and S(7,459ppm), and salt water from the Chunil salt contained small amounts of Pb, Al, Cr and Hg. Processed salts contained high levels of Ca, K, Mg and Fe. Especially, high levels of K, P, Fe and Ge were detected in bamboo salt. Purified salts showed regular crystal form and raw salts exhibited irregular crystal form under the SEM. The processed salts were not crystal form, but fused and irregular round form.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.193-199
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• 2017

In this study, changes of soil properties including soil texture, specific surface area, organic matter content, pH, cation exchange capacity and exchangeable cations content were investigated in response to strong acid or base accident. The properties changed significantly when the soil reacted with 10 M HCl or 1 M NaOH (i.e., when one gram of soil received 50 and 5 mmol of HCl or NaOH), respectively. When the soil reacted with 10 M HCl or 1 M NaOH solution, soil texture changed from sandy loam to loamy sand and specific surface areas decreased from $5.84m^2/g$ to 4.85 and $1.92m^2/g$, respectively. The soil organic matter content was reduced from 3.23% to 0.96 and 0.44%, and the soil pH changed from 5.05 to 2.35 and 10.65, respectively. The cation exchange capacity decreased from 10.27 cmol/kg to 4.52 and 5.60 cmol/kg, respectively. Especially, high concentrations of $Al^{3+}$ or $Na^+$ were observed in acidic or basic spills, respectively, which is likely to cause toxicity to terrestrial organisms. The results suggest that restoration of soil properties, as well as soil remediation, needs to be carried out to maintain the soil function in chemical spill sites.