• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.215-219
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• 1998

This experiment was conducted to investigate effects of NaCl concentration on photosynthetic rate, free proline content and ion content in tobacco. As NaCl concentration was increased growth was retarded. The decrease growth characteristics(shoot/root ratio was 2.0) at 90mM NaCl indicated that this concentration could be a limiting level. As NaCl concentration was increased photosynthetic rate, transpiration rate, and water use efficiency were decreased. Photosynthetic rate was highly decreased at 60mM NaCl. There was no significant difference between transpiration rate and water use efficiency. Leaf water potential was decreased as NaCl concentration was increased, in that twice lower at 30mM than that of control and drop largely at 120mM NaCl. Free proline content was increased as NaCl increased until 120mM NaCl and drop at 150mM NaCl. The $Ca^{2+}$, $Mg^{2+}$, and $K^+$ contents were increased until NaCl concentration was 120mM. The $Na^{2+}$ content was slowly increased as NaCl concentration increased until 120mM NaCl, and largely increased at 150mM NaCl. There was no significant difference between $Cl^-$ and NaCl treatments except 30 mM NaCl in which $Cl^-$ content was higher than that of control. As NaCl concentration was increased $K^+/Na^+$ ratio was decreased. The negative correlation between $K^+$ and $Na^+$, and positive correlation between $K^+/Na^+$ and protein content were found.

• Korean Journal of Materials Research
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• v.28 no.1
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• pp.50-61
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• 2018

Various carbon aerogels (CAs) were prepared from polymerization of resorcinol and formaldehyde and applied as the electrode materials of an electric double layer capacitor (EDLC) with the aim of controlling the textural and electrochemical properties of CAs by the type of base catalyst and the ratio of resorcinol to catalyst (R/C). The CAs from $NaHCO_3$ and $KHCO_3$ with $H^+$ ions had higher specific surface areas but exhibited lower electrochemical properties than those from $K_2CO_3$ and $Na_2CO_3$, which had more uniform pore size distributions. The electrochemical properties of $Na_2CO_3$ were superior to those of $K_2CO_3$ probably because the polarizing power of $Na^+$ ions was higher than $K^+$ ions. With an increasing R/C ratio, the pore sizes of CA showed a tendency to increase but the uniformity of the pore size distribution got worse. For the four base catalysts, the highest electrochemical property was obtained at the R/C ratio of 500.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.135-139
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• 2016

We developed a liquid-liquid extraction method using an inorganic salt to dramatically improve the recovery efficiency of the anticancer agent paclitaxel from plant cell cultures. As a result of liquid-liquid extraction using a diverse types of inorganic salt (NaCl, KCl, $K_2HPO_4$, $NaH_2PO_4$, $NaH_2PO_4{\cdot}2H_2O$), NaCl gave the highest yield (~96%) and lowest partition coefficient (0.053) of paclitaxel. The optimal NaCl/solvent ratio, methylene chloride/MeOH ratio, and pure paclitaxel content for liquid-liquid extraction using NaCl were 1% (w/v), 26% (v/v), and 0.066% (w/v), respectively. Under the optimal conditions developed in the present method, most of the paclitaxel (~96%) was recovered from biomass by a single extraction step. In addition, this method facilitated 3-fold higher recovery efficiency of paclitaxel in a shorter extraction number than the conventional liquid-liquid extraction method.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.331-338
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• 2014

In this research, split-type complex yarn of 20:80, 40:60, 50:50 nylon6/polyester composition ratio was used in order to impose unique sense on split-type complex woven. After treating both split-type complex yarn of each ratio and its produced woven in alkali solution, we got the following results by checking physical properties based on alkali proportion and treatment time. Under the condition of NaOH 20% in this experiment, it took approximately double time 20% loss of weight. The loss of weight became high when polyester proportion of N/P(nylon6/polyester) composition ratio was low, in the same fineness yarn. Even though polyester proportion was low, the loss of weight was low when the fineness was high. N/P division was well processed at about 25% loss of weight under the condition of NaOH 20%, treatment temperature $50^{\circ}C$, and treatment time 60 minutes. The research provides that the loss of weight should be processed around treatment time 24 hours in the case of NaOH concentration 15%, and treatment time 15 hours in the case of NaOH concentration 18%, respectively, in order to achieve N/P woven division ratio of about 70%-80% in industrial fields.

• Current Photovoltaic Research
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• v.7 no.4
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• pp.103-110
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• 2019

Cu(In,Ga)₃Se₅ (β-CIGS) has a band gap of 1.35 eV, which is an optimum value for high solar-energy conversion efficiency. The effects of Cu and Ga content on the cell performance were investigated previously. However, the effect of Se content on the cell performance is not well understood yet. In this work, β-CIGS films were fabricated by three-stage co-evaporation of elemental sources with various Se fluxes at the third stage instead of at all stages. The average composition of five samples was Cu_1.05(In_0.59,Ga_0.41)3Se_y, where the stoichiometric y value is 5.03 and the stoichiometric Se/metal (Se/M) ratio is 1.24. We varied the Se/metal ratio in a range from 1.18 to 1.28. We found that the best efficiency was achieved when the Se/M ratio was 1.24, which is exactly the stoichiometric value where the CIGS grains on the CIGS surface were tightly connected and faceted. With the optimum Se/M ratio, we were able to enhance the cell efficiency of a β-CIGS solar cell from 9.6% to 12.0% by employing a Na₂S post deposition treatment. Our results indicate that Na₂S post deposition treatment is very effective to enhance the cell efficiency to a level on par with that in α-CIGS cell.

• The Korean Journal of Physiology
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• v.11 no.1
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• pp.11-20
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• 1977

The action of pilocarpine on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action of pilocarpine on the ATPase activity. The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by pilocarpine, and the concentration of pilocarpine for maximal activity is about 3 mM. The pH optimum for the pilocarpine sensitive component is 8.0. 2. The activating effect of pilocarpine on the ATPase, with a given concentration of sodium .in the medium, is increased by raising the potassium concentration but activity ratio is decreased 3. The activating effect of pilocarpine on the ATPase, with a given concentration of Potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased 4. The NaK ATPase activity is increased by small amounts of calcium but decreased by 'larger amounts. The activity ratio of the enzyme by pilocarpine is decreased by small amounts .of calcium but decreased by larger amounts. 5. The activating effect of pilocarpine on the ATPase was not related to the sulfhydryl group of cysteine, the hydroxyl group of threonine or the imidazole group of histidine. 6. The activating effect of pilocarpine on the ATPase is due to amino group and carboxyl group of the enzyme of NaK ATPase

• Journal of the East Asian Society of Dietary Life
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• v.26 no.4
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• pp.297-307
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• 2016

This study was performed to investigate the nutritional status associated with hypertension. The subjects were composed of 52 middle aged men divided into normotensive and hypertensive groups according to the Joint National Committee(JNC)-7 criteria. The mean blood pressures of the normotensive and hypertensive groups were $109.8{\pm}1.8$ / $68.9{\pm}1.7mmHg$, and $146.8{\pm}4.6$ / $90.5{\pm}2.9mmHg$, respectively. The percent body fat (PBF), waist to hip ratio (WHR), and serum levels of total cholesterol, LDL-cholesterol, Na, Cl, alanine transferase (ALT), and atherogenic index (AI) were significantly higher in the hypertensive group than normotensive group. The intakes of energy, protein, lipid, vitamin B1, niacin, and intake ratio of Na/K were significantly higher in the hypertensive group than normotensive group. Our findings suggest that decreasing PBF, WHR, serum levels of total cholesterol, LDL-cholesterol and NaCl may play an important role in the prevention of hypertension. It also suggests that decreasing intakes of energy, protein, lipid, vitamin B1, niacin, and Na/K ratio are crucial in order to prevent hypertension.

• Mass Spectrometry Letters
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• v.8 no.1
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• pp.14-17
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• 2017

The effect of cationization agent concentration on glycan detection via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was investigated using $Na^+$ ions in the form of NaCl as the cationization agent. NaCl solution concentrations ranging from 1 mM to 1 M were investigated. Glycans from ovalbumin were mixed with the cationization agent solution and the 2,5-dihydroxybenzoic acid (2,5-DHB) matrix solution in a volume ratio of 1:1:1. The resulting mixture was loaded onto the MALDI plate. Two MALDI-TOF MS instruments (Voyager DE-STR MALDI-TOF MS and Tinkerbell RT MALDI-TOF MS) were used for detection of glycans. The best detection, in terms of the number of identified glycans, the peak intensity, and the signal-to-noise (S/N) ratio, was obtained with NaCl concentrations of 0.01-0.1 M for both MALDI-TOF MS instruments.

• The Korean Journal of Physiology
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• v.20 no.2
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• pp.184-191
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• 1986

Membrane potential of cells in the isolated rabbit coronary sinus was measured by conventional glass microelectrode and investigated the effect of $[K^+]_0$ variation in control, 20 mM and Ach-containing Tyrode solution. The results obtained were as follows: 1) The resting membrane potential exposed to normal Tyrode solution containing 3 mM $K^+\;was\;about\;-60{\sim}\;-65mV$. At extracellular $K^+$ concentrations from 1 to 30 mM the resting Potential was reasonably well described by Goldman -Hodgkin -Katz equation on the assumption that $[K^+]_1$ was 150 mM and that the ratio of membrane permeability coefficient for $Na^+\;and\;K^+,\;P_{Na}/P_K\;({\alpha})$ was 0.07. 2) In 20 mM Na-Tyrode solution (replacing by equimolar Tris) the resting membrane potential was hyperpolarized by 15 to 20 mV and showed slightly deviated to depolarized direction compared to the predicted value by Goldman-Hodgkin -Katz equation. 3) In the presence of $10^{-6}M$ Ach, the resting potentials at $[K^+]_0$ levels from 1 to 30 mM were well fitted with the predicted value on the assumption that $P_{Na}/P_K$ was 0.0144. It could be concluded that the low resting membrane potential of coronary sinus cells reflects a relatively high ratio $P_{Na}/P_K$ of about 0.07.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.3
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• pp.137-141
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• 2006

The systolic and diastolic pressures in anesthetized Sprague-Dawley male rats were greatly decreased after single-dose of Cd treatment without significant changes in heart rate. There was a fluid-shift into the third space and/or -loss through the kidney, since plasma $Na^+$ concentration and hematocrit ratio were significantly increased by acute Cd exposure. The present study showed that the sustained hypotensive effect of single-dose Cd on the cardiovascular system might have resulted from the systemic hypovolemia. Furthermore, renal excretion of electrolytes, including $Na^+$ and $K^+$, and urine flow rate were increased by Cd intoxication. Interestingly, the ratio of $Na^+/K^+$ excretion was increased and reached the maximum level 3 hours after Cd injection and returned to the normal level after 7 hours. Nevertheless, there was no difference in the regression analysis of $Na^+$ excretion and urine flow rate in both groups. Therefore, the increase in the urine volume seemed to enhance the excretion of $Na^+$. This study strongly suggest that the hypotensive effect of Cd is mediated by systemic $Na^+$ loss through the kidney and/or hypovolemia via fluid-shift.