• Journal of Yeungnam Medical Science
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• v.3 no.1
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• pp.229-235
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• 1986

Lithium salts are being used increasingly to treat patient with affective disorders, especially acute mania, or bipolar manic-depressive illness. For therapeutic effect the lithium content must be maintained at or above a particular level. Lithium poisoning due to overdosage may be seen occasionally, and its course is determined primarily by the rate of renal lithium elimination. A search is therefore indicated for procedures that could raise the lithium clearance. In a number of reports renal lithium excretion has been studied in relation to the excretion of water, sodium, potassium and hydrogen, but effects of sodium or water on the lithium excretion has not yet been clarified. Hence the present study was undertaken to investigate the effects of corticosteroid on the excretion of lithium ion. The female rat(Sprague-Dowley), weighing from 200 to 300g, was injected with 50mg/kg of lithium chloride intraperitoneally, and then injected with graded dosage of fludrocortisone and dexamethasone in each group. During the injected rats were incubated in metabolic cage, 24 hour urine of rats were collected. At 24 hours after injection, the rats were sacrificed with guillotin, the blood were collected. And then the concentratios of $Na^+$, $K^+$, $Li^+$ of collected urine and serum were checked by Flame photometer. The results are summarized as follows; 1. Fludrocortisone decreased the serum concentration of lithium and increased the urinary excretion of lithium. 2. In the group treated with low dose of dexamethasone(0.1mg/kg), the serum concentration of lithium was decreased and high dose of dexamethasone (1mg/kg) increased the urinary excretion of lithium. 3. Fludrocortisone increased the urinary $[Na^+]/[K^+]$ in serum and decreased $[Na^+]/[K^+]$ in urine, but opposite effects were occurred in dexamethasone. By above results, it may be concluded that corticosteroid increased the urinary excretion of lithium and decreased the serum concentration of lithium, but it seems to be there is no relationship between these effects of corticosteroid and of the renal $Na^+$ or $K^+$ transport.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.3
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• pp.173-183
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• 2000

This study measured the zeta potential of both latex colloidal particles with carboxylate surface groups and glass beads (collectors) with silanol surface group employing various solution with different chemical characteristics. The results have been compared with the surface chemistry theory. The zeta potential of the particle and collector increased with increasing pH up to 5.0 regardless of the solution chemistry. For a monovalent electrolyte solution(sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (calcium chloride solution). In other words, the more the pH decreases, the larger the effect of neutral salts, such as NaCl and CaCl$_2$, have on the ζ-potential values. In this study, the PZPC(point of zero proton condition) of the particle and collector occurred below a pH of 3.1, H(sup)+ and OH(sup)- acted as a PDI (potential determining ion), and Na(sup)+ acted as an IDI(indifferent ion). The magnitude of the negative ζ-potential values of the particle and collector monotonically increased as the concentrations of Na(sup)+ or Ca(sup)2+([Na(sup)+] or [Ca(sup)2+]) decreased (the values of pNa or pCa increased). In the case of latex particles, the ζ-potential should aproach zero (isoelectric point; IEP) asymptotically as the pNa approaches zero, while in the case of calcium chloride electrolyte, ζ-potential reversal may be expected to occur around 3.16$\times$10(sup)-2MCaCl$_2$(pCa=1.5). pH, valance and ionic strength can be used in various ways to improve the water treatment efficiency by modifying the charge characteristics of the particle and collector. Predictive capability is far less certain when EDL(electrical double layer) repulsive forces exist between the particle and collector.

• YAKHAK HOEJI
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• v.56 no.3
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• pp.164-172
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• 2012

This study was aimed to increase the solubility, dissolution and permeation rates of atorvastatin calcium (ATC) using bile salt and/or 2-hydroxypropyl-${\beta}$-cyclodextrin ($HP{\beta}CD$). From solubility studies, sodium deoxycholate (SDC) among bile salts studied was found to have the highest solubilizing effect on ATC ($4.4{\pm}0.4$ mg/ml), and the order of increasing solubility was SDC>sod. cholate>sod. glycocholate>sod. taurodeoxycholate>sod. taurocholate>conjugated bile acid. ATC solid dispersions were prepared at various ratios of drug to SDC and/or $HP{\beta}CD$, and evaluated by differential scanning calorimetry (DSC), dissolution studies and dissolution-permeation studies. DSC curves showed amorphous state of ATC in the physical mixture and solid dispersion. Dissolution rates of ATC-SDC solid dispersions and physical mixture were markedly increased at pH 6.8, but decreased at pH 1.2 with greater proportions of SDC due to the precipitation of SDC, compared with that of drug alone. On the other hand, dissolution rates of ATC-$HP{\beta}CD$ solid dispersion and physical mixture at pH 1.2 were varied with the ratio of drug to carriers. From duodenal permeation studies, it was found that fluxes of ATC (donor dose: 0.5 mg/3.5 ml) in the presence of 25 mM sodium glycocholate, SDC, sod. cholate and sod. taurocholate $(5.7{\pm}0.9$, $5.6{\pm}0.9$, $4.8{\pm}0.7$ and $4.6{\pm}0.9\;{\mu}g/cm^2/hr$, respectively) were enhanced, compared with drug alone ($3.4{\pm}0.9\;{\mu}g/cm^2/hr$). In the dissolution-permeation studies, 1 : 9 : 10 (w/w) ATC-SDC-$HP{\beta}CD$ solid dispersion increased the flux 2.2 times, compared with 1 : 5 : 4 (w/w) ATC-lactose-corn starch mixture as control. In conclusion, solid dispersions with bile salt and $HP{\beta}CD$ were found to be an effective means for increasing the dissolution and permeation rates of ATC.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.326-328
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• 2004

Domestic pear has been reported that it contained a pretense, which used for tenderizer of meat, however no researches for optimum level of the enzyme with maximum tenderness effect have been studied. Thus, this study was peformed to determine the optimum level of a protease for meat tenderness. Moisture contents (％) of domestic pears was determined. A pretense was homogenized in a mixer and centrifuged at 10,000 G for 1hr. After taken the supernatant, dialysis was conducted to remove salts and sugars, and freeze-dried. Then, various level (0.05, 0.1 and 0.2％) of the purified pretense were added to pork loins (3cm thickness). Then, pork samples were boiled at 80 for 12 min in a water bath to reach the interval temperature of 71 and chilled in an ice. Moisture contents (％) of domestic pears ranged from 87.2 and 87.8％. No differences in cooking loss of pork meats were observed (p>0.05) among various levels of a pretense. After centrifugation, the protein concentrations of a protease showed from 5.96 $\mu\textrm{g}$/fmL to 7.25 $\mu\textrm{g}$/mL. Increased level of a pretense up to 0.1％ reduced (p<0.05) the shear value (kg/g), however no further reduction of shear value was observed at the level of higher than 0.1％ of the purified pretense. The approximate molecular weight of the pretense analysed by sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was 30 kDa. These results suggest that the optimum level of a pretense for the maximum effect of meat tenderness is above 0.1％. Further research will be peformed to determine the effect of various domestic pears and ingredients, such as salt and phosphate, on meat tenderness.

• Journal of Pharmaceutical Investigation
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• v.26 no.1
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• pp.1-11
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• 1996

Biphenyldimethyldicarboxylate (PMC), which has been used to treat hepatitis, is insoluble in water, therefore it has low bioavailability after oral administration. For the purpose of increasing the dissolution rate of PMC, the physical mixtures and inclusion complexes of PMC and $dimethyl-{\beta}-cyclodextrin\;(DM\;{\beta}CD)\;or\;hydroxypropyl-{\beta}-cyclodextrin\;(HP{\beta}CD)$ in molar ratio of 1 : 1 and 1 : 2 were prepared by solvent evaporation method. Mixed micelles of PMC were prepared by reacting PMC with bile salts [sodium cholate(NaC), sodium glycocholate (NaGC)] and oleic acid (OA) or palmitoylcarnitine chloride(PCC). Chloroform/water partition coefficient (PC) of PMC was 36.14 in artificial gastric juice (AGJ) and 33.47 in artificial intestinal juice (AIJ), respectively, on the other hand octanol/water PC was 63.36. PMC formulation was prepared by reacting PMC with PEG400-glycerin system(95 : 5, 90 : 10, respectively) and PEG400-PEG4000-glycerin system (70 : 25 : 5, 65 : 25 : 10, respectively). Dissolution test was performed in AGJ and AIJ by paddle method at $37{\pm}0.5^{\circ}C$. The dissolution rates of PMC tablets on the market were 5.74% and 8.26% at AGJ and AIJ, respectively and marketed PMC capsules were 22.14% and 28.64% at AGJ and AIJ, respectively. The dissolution rates of inclusion complexes of PMC with $DM{\beta}CD$ and $HP{\beta}CD$ in a molar ratio of 1 : 1 were more fast than those of corresponding physical mixtures. The decreasing order of dissolution rates was as follows; PMC-PEG400-PEG4000-glycerin formulation > PMC-PEG400-glycerin formulation > mixed micelles > CD inclusion complexes. The dissolution rates of PMC-PEG400-glycerin and PMC-PEG400-PEG4000-glycerin formulation were most fast and the percentage of dissolution was almost 100% within 20 minutes. And their dissolution rates after 120 minutes were markedly increased as compared with capsules on the market (4.0-fold and 3.2-fold in PMC-PEG400-glycerin formulation at AGJ and AIJ, respectively, and 4.8-fold and 3.7-fold in PMC-PEG400-PEG4000-glycerin formulation at AGJ and AIJ, respectively).

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.297-302
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• 1988

The protoplasts of Saccharomyces cerevisiae D-71, a thermophilic strain and Zygosaccharomyces rouxii SR-S, an osmotolerant strain were fused, and a fusant (FS-RN 1) was selected, then was characterized for its genetic stability, DNA content, cell capacity, growth rate, tolerance to salts and chemicals, $\beta$-fructofuranosidase level and ethanol fermenting activity. After 6 months of preservation, 5.8% of the fusant clones were segregated to parental types. The DNA content and cell capacity of the fusant were greater than those of the parental strains. Lag period of growth for the fusant was longer than those for the parents. The fusant colonies showed pink-color reaction to triphenyltetrazolium chloride(TTC) test. The fusant appeared to have resistances to NaCl at moderate levels between both parental strains, and resistances to KCI, sodium propionate and cycloheximide similar to either one of the parents. $\beta$-Fructofuranosidase activity of the fusant was 24.2$\times$10$^{-3}$/IU/g(dry wt) for 3 days culture. Ethanol yields ofter 4 days of fermentation by the fusant at 3$0^{\circ}C$ were : 6.0%(v/v) from 40% of glucose and 8.8%(v/v) from 20% of sucrose.

• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.384-388
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• 2019

In winter season, the snow and ice accretion on the bottom of the high speed railway rolling stock and boogie part has fallen at a high speed from the ballast section (gravel section for the transmission of the rolling stock load received by sleepers and fixing sleepers), causing the gravel to be scattered, thereby damaging the railway rolling stock structures and facilities. In order to solve these problems, the gravel scattering prevention net, manual de-icing, and movable hot air machine were used, but their efficiency was low. For the more efficient de-icing than ever before, an optimum material for de-icing fluid for high speed railway rolling stock was developed by evaluating the ice melting capacity, kinematic viscosity, evaporation of the material used as a chemical de-icing fluid. Four kinds of organic acid salts (sodium formate, sodium acetate, potassium formate and potassium acetate) and two different alcohols (propylene glycol, glycerol) were used as evaluation materials. Potassium formate, potassium acetate, and propylene glycol had similar ice melting capacities in the indoor test, but the propylene glycol showed the best ice melting capacity in spraying the system simulation test. This is because the kinematic viscosity of propylene glycol was 2.989029 St, which is higher than those of other materials therefore, it could stay longer on the ice and de-icing. In addition, potassium formate and potassium acetate were difficult to be used since the crystals precipitated and adversely affected the appearance of the rolling stock. The propylene glycol is the most optimum as an de-icing fluid for the high speed railway rolling stock.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.4
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• pp.227-238
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• 2013

The purpose of this study is to develop a process technology to produce high hardness drinking water which meet drinking water standard, remaining useful minerals like magnesium and calcium in the seawater desalination process while removing the sulfate ions and chloride ions. Seawater have been separated the concentrated seawater and desalted seawater by passing on Reverse Osmosis membrane (RO). Using Nano-filtration membrane (NF), We were prepared primary mineral concentrated water that sodium chloride were not removed. By the operation of electro-dialysis (ED) having ion exchange membrane, we were prepared concentrated mineral water (Mineral enriched desalted water) which the sodium chloride is removed. We have produced the high hardness water to meet the drinking water quality standards by diluting the mineral enriched desalted water with deionized water by RO. Reverse osmosis membranes (RO) can separate dissolved material and freshwater from seawater (deep seawater). The desalination water throughout the second reverse osmosis membrane was completely removed dissolved substances, which dissolved components was removed more than 99.9%, its the hardness concentration was 1 mg/L or less and its chloride concentration was 2.3 mg/L. Since the nano-filtration membrane pore size is $10^{-9}$ m, 50% of magnesium ions and calcium ions can not pass through the nano-filtration membrane, while more than 95% of sodium ions and chloride ions can pass through NF membrane. Nano-filtration membrane could be separated salt components like sodium ion and chloride ions and hardness ingredients like magnesium ions and calcium ions, but their separation was not perfect. Electric dialysis membrane system can be separated single charged ions (like sodium and chloride ions) and double charged ions (like magnesium and calcium ions) depending on its electrical conductivity. Above electrical conductivity 20mS/cm, hardness components (like magnesium and calcium ions) did not removed, on the other hand salt ingredients like sodium and chloride ions was removed continuously. Thus, we were able to concentrate hardness components (like magnesium and calcium ions) using nano-filtration membrane, also could be separated salts ingredients from the hardness concentration water using electrical dialysis membrane system. Finally, we were able to produce a highly concentrated mineral water removed chloride ions, which hardness concentration was 12,600 mg/L and chloride concentration was 2,446 mg/L. By diluting 10 times these high mineral water with secondary RO (Reverse Osmosis) desalination water, we could produce high mineral water suitable for drinking water standards, which chloride concentration was 244 mg/L at the same time hardness concentration 1,260 mg/L. Using the linked process with reverse osmosis (RO)/nano filteration (NF)/electric dialysis (ED), it could be concentrated hardness components like magnesium ions and calcium ions while at the same time removing salt ingredients like chloride ions and sodium ion without heating seawater. Thus, using only membrane as RO, NF and ED without heating seawater, it was possible to produce drinking water containing high hardness suitable for drinking water standard while reducing the energy required to evaporation.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.169-173
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• 2010

Many salts have the ability to attract and remove water vapor from the surrounding environment. The ability of each salt to remove water vapor is based on the flow rate and temperature of air in surrounding. The objective of this study was toinvestigate the humid control characteristics in air-water system by using a desiccants. The aim is to asses the influence of three parameters on the humid control process which are air volume rate, air temperature and desiccant amount. Humidity control materials which consist of K (potassium) or Na (sodium) have been synthesized by the aqueous process. The humidity control properties of materials have been also investigated. Experiment results are as following. Thermal characteristics of desiccants showed similar properties regardless of processing condition. The experiments were examined by using artificial air-water system (humidity : 70~93%, air volume rate : $0.22{\sim}0.69m^3/s$). The results showed that the Na-type desiccant was an effective material. It was found that dew point increased with air volume rate, and the humidity change in humid control process was depended on desiccants amount.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.5
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• pp.638-648
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• 2004

In many drinking water treatment plants, chlorination process is one of the main techniques used for the disinfection of water. This disinfecting treatment leads to the formation of haloacetic acid (HAAs). In this study, headspace solid-phase microextraction (HS-SPME) was studied as a possible alternative to liquid-liquid extraction for the analysis of HAAs in drinking water. The method involves direct derivatization of the acids to their methyl esters without methyl tert-butyl ether (MTBE) extraction, followed by HS-SPME with a $2cm-50/30{\mu}m$ divinylbenzene/carboxen/polydimethylsiloxane fiber. The effects of experimental parameters such as selection of SPME fiber, the volume of sulphuric acid and methanol, derivatization temperature and time, the addition of salts, extraction temperature and time, and desorption time on the analysis were investigated. Analytical parameters such as linearity, repeatability and limit of detection were also evaluated. The $2cm-50/30{\mu}m$-divinylbenzene/carboxen/polydimethylsiloxane fiber, sulphuric acid of 1ml, methanol of 3ml, derivatization temperature of $50^{\circ}C$ derivatization time of 2hrs, sodium chloride salt of 10g, extraction time of 30 minutes, extraction temperature of $20^{\circ}C$ and desorption time of 1 minute at $260^{\circ}C$ were selected as the optimal experimental conditions for the analysis of HAAs. The linearities ($r^2$), relative standard deviations (%RSD) and limits of detection (LOD) for HAAs were 0.9978~0.9991, 1.1~9.8% and $0.05{\sim}0.2{\mu}g/l$, respectively.