• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.189-197
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• 1994

Analytic methods for Cr(VI) level in industrial hygienic field were suggested by the National Institute for Occupational Safety and Health(NIOSH method 7600, 7604). There were growing needs for measurement of Cr(III) and Cr(VI) levels simultaneously. Two analytical methods were suggested to determine Cr(III) and Cr(VI) levels simultaneously. The one is method by using reversed phase high peformance liquid chromatography(HPLC) and the other is by using ion exchange HPLC. The purpose of this work was to evaluate the usefulness of these two analytic methods. For the difference of ionic charges of Cr(III)-ethylendiamine tetraacetic acid(EDTA) chelate and $CrO_4{^-2}$, we could detect them simultaneously by ion exchange HPLC. Also, we attempted to determine the levels of Cr(III) and Cr(VI) chelated with sodium diethyldithiocarbamate(NaDDTC) by using reversed phase HPLC. The confirmation of Cr(III) and Cr(VI) were checked by fraction collector and nameless atomic absorption spectrometer. The optimal conditions for the formation of Cr(III)-EDTA chelate were two hours incubation period with pH 5. Cr(III)-EDTA and Cr(VI) in EDTA solution were successfully separated by anion exchange column using $Na_2CO_3/NaOH$ mixture as mobile phase. Peaks of Cr(III)-EDTA and Cr(VI) in EDTA were identified at 5 minutes and 7 minutes of retention time respectively by the ion exchange HPLC. The formation of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were twelve hours incubation period. Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were separated by reversed phase column using methanol and water mixture as mobile phase. Peaks of Cr(VI)NaDDTC and Cr(III)-NaDDTC chelates were identified at 13 minutes and 26 minutes of retention time respectively by the reversed phase HPLC. Due to reduction of Cr(VI) to Cr(III), it seems to be not suitable for simultaneous determination of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates by reversed phase HPLS. Simultaneos determination of Cr(III) and Cr(VI) by ion exchange HPLC was more accurate and simple method.

• Analytical Science and Technology
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• v.8 no.4
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• pp.419-425
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• 1995

A method has been investigated for the determination of selenium and tellurium in Ginseng, Ganoderma and Garlic using hydride generation atomic absorption spectrometry(HG-AAS). The concentration effects of hydrochloric acid and sodium tetrahydroborate on the hydride generation for the determination of selenium and tellurium were investigated. The method of sample decomposition was also investigated using various mineral acids, such as nitric, perchloric and sulfuric acid in the closed system, and foreign ion effects containing in the samples were studied. The calibration curves of selenium and tellurium were obtained in the range of 0~40 ppb. The detection limits(S/N=2) of selenium and tellurium are 0.1 and 0.2 ppb. Analytical data of selenium and tellurium in Garlic, Ganoderma and Ginseng are 289, 296 and 198 ng/g for selenium and 146, 127 and 110 ng/g for tellurium, respectively.

• Childhood Kidney Diseases
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• v.20 no.1
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• pp.11-17
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• 2016

Appropriate control of diet and water intake is important for maintaining normal blood pressure, fluid and electrolyte homeostasis in the body. It is relatively understood that the amount of sodium and potassium intake directly affects blood pressure and regulates ion transporters; Na and K channel functions in the kidney. However, little is known about whether diet and water intake regulates Aquaporin (AQP) function. AQPs, a family of aquaporin proteins with different types being expressed in different tissues, are important for water absorption by the cell. Water reabsorption is a passive process driven by osmotic gradient and water permeability is critical for this process. In most of the nephron, however, water reabsorption is unregulated and coupled to solute reabsorption, such as AQP1 mediated water absorption in the proximal tubule. AQP2 is the only water channel founded so far that can be regulated by hormones in the kidney. AQP2 expressed in the apical membrane of the principal cells in the collecting tubule can be regulated by vasopressin (antidiuretic hormone) controlling the final volume of urine excretion. When vasopressin binds to its receptor on the collecting duct cells, it stimulates the translocation of AQP2 to the membrane, leading to increased water absorption via this AQP2 water channel. However, some studies also indicated that the AQP2 is also been regulated by vasopressin independent mechanism. This review is focused on the regulation of AQP2 by diet and the amount of water intake on salt and water homeostasis.

• Journal of the Korean Chemical Society
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• v.25 no.3
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• pp.160-165
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• 1981

Radical copolymerization of the complexed 2-vinylpyridine with vinyl acetate and divinylbenzene initiated by azobisisobutyronitrile was carried out in N, N-dimethylformamide in presence of barium chloride at $98{\circ}C$. In the preparation of 2-vinylpyridine-vinylacetate-divinylbenzene terpolymer, the optimum reaction conditions were studied by means of various temperatures and times. 2-vinylpyridine-vinylalcohol-divinybenzene resin was prepared by transesterificating 2-vinylpyridine-vinylacetate-divinylbenzene terpolymer with a 1% methanolic sodium hydroxide solution. 2-Vinylpyridine-vinylphosphate-divinyldenzene was prepared by phosphorylating 2-vinylpyridine-vinylalcohol-divinylbenzene resin with phosphoric acid and urea. The compositions of each synthetic resin were identified by means of infrared absorption spectroscopy. The ion exchange capacities of each 2-vinylpyridine-vinylalcohol-divinylbenzene and 2-vinylpyridine-vinylphosphate-divinylbenzene terpolymer was 3.69 meq/g and 5.38 meq/g.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.39-45
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• 2017

In this study, permeable repair materials mainly composed of silicate - based inorganic materials(SIM), which are easily available domestically, were prepared as a basic study for the development of permeable repair materials using SIM. SIM were compared and examined for their performance as repair materials by selecting a product group which has many cases of use in foreign countries. The SIM used were mainly composed of sodium, potassium and lithium silicate. Performance evaluation of SIM was performed by absorption and penetration, compression and adhesion, rapid chloride ion penetration, rapid freezing and thawing, and chemical resistance test. According to the test results, SIM showed effective performance in all areas, mainly because SIM permeates into the interior of the capillary and has a dense internal microstructure. Therefore, it can be used variously to improve the durability of concrete based on the results of this experiment.

• The Korean Journal of Physiology
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• v.7 no.2
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• pp.39-47
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• 1973

The influences of the acute hemorrhage on the intestinal functions were studied in the rabbits subjected to acute bleeding, amounting 1.5-2% of the body weight. The motility and the absorptive capacity of the ileum were compared before and after the bleeding. Transfusion of shed blood was also performed in order to see whether the deteriorations were reversible or not. The tension developed in the direction of the longitudinal axis of the ileum was recorded through an appropriate transducer, and the frequency of the rhythmic contraction was counted throughout the procedure. Test solution, 10ml in amount, was placed in the loop of the ileum, and the samples were drawn at zero time and at 20 minutes. Triplicated procedures were repeated on the same loop;namely, before and after bleeding and after transfusion. The test solution was composed of 200 mg% urea, 218 mEq/l of NaCl and 150 mg% of polyethylene glycol (PEG) No. 4,000 in distilled water. The latter substance was used as a marker substance for the volume change of the loop. The results obtained were as follows; 1. The motility of the ileum suffered little effects by acute hemorrhage. However, minor fluctuations were seen in the frequency of the rhythm, showing a slight tendency of decreasing rhythmicity, and it was reversed by transfusion. 2. Diminution of absorptive capacity of urea was noticed in acute hemorrhage and it was interpreted as the consequence of the secondary effect of the retardation of the active transport mechanism governing the sodium transport 3. Absorption rate of the sodium ion was dropped in the hemorrhage, suggesting the indispensable need of the blood supply. 4. Osmolarity of the luminal fluid remained higher in the case of acute hemorrhage. 5. There was a tendency of retaining more fluid in the intestinal lumen in acute hemorrhage, comparing with that observed prior to the bleeding. 6. The deteriorations in the absorptive capacity were restored by transfusion of shed blood.

• Journal of the Korean Chemical Society
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• v.38 no.12
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• pp.891-897
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• 1994

A method has been investigated for the determination of Selenium in Ginseng radix, Ganoderma Lucidum and Garlic using hydride generation atomic absorption spectrometry (HG-AAS). The effects of several acids and sodium tetrahydroborate concentration and their flow rate on the determination of Selenium for the hydride generation were investigated. The method of sample decomposition was also investigated using various mineral acids, such as nitric, perchloric and sulfuric acid in the closed system and foreign ion effects were studied. In the optimum conditions, we obtained calibration curve in the range 0-40 ppb. The analytical data of Garlic, Ganoderma Lucidum and Ginseng radix are 289, 296, 198 ppb, respectively.

• Clinical and Experimental Pediatrics
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• v.46 no.3
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• pp.308-311
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• 2003

Congenital chloride diarrhea is a serious autosomal recessive disease, and defect of intestinal electrolyte absorption that involves, specifically, $Cl^-/{HCO_3}^-$ exchange in the distal part of the ileum and colon. The clinical feature is dominated by profuse, watery diarrhea containing high concentrations of chloride(>90 mmol/L) and sodium. The chloride loss results in severe dehydration with a hypochloremic alkalosis. The molecular pathology involves an epithelial $Cl^-/{HCO_3}^-$ exchanger protein. Mucosal ion transport is affected to differing degrees and the severity of the disease may thus vary. Recently, a gene defect on chromosome 7 has been identified. However, there was a deficit in replacement of fluid and electrolyte, abdominal distension remained and the character of stools was watery. We report a case of congenital chloride diarrhea in a premature female who presented with watery diarrhea containing high concentrations of chloride and abdominal distension.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.3
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• pp.231-241
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• 2001

The mammalian cortical collecting duct (CCD) plays a major role in regulating renal NaCl reabsorption, which is important in $Na^+$ and $Cl^-$ homeostasis. The M-1 cell line, derived from the mouse cortical collecting duct, has been used as a mammalian model of the study on the electrolytes transport in CCD. M-1 cells were grown on collagen-coated permeable support and short circuit current $(I_{sc})$ was measured. M-1 cells developed amiloride-sensitive current $5{\sim}7$ days after seeding. Apical and basolateral addition of ATP induced increase in $I_{sc}$ in M-1 cells, which was partly retained in $Na^+-free$ or $Cl^--free$ solution, indicating that ATP increased $Na^+$ absorption and $Cl^-$ secretion in M-1 cells. $Cl^-$ secretion was mediated by the activation of apical cystic fibrosis transmembrane regulator (CFTR) chloride channels and $Ca^{2+}-activated$ chloride channels, but $Na^+$ absorption was not mediated by activation of epithelal sodium channel (ENaC). ATP increased cAMP content in M-1 cells. The RT-PCR analysis demonstrated that M-1 cells express $P2Y_2,\;P2X_3\;and\;P2Y_4$ receptors. These results showed that ATP regulates $Na^+$ and $Cl^-$ transports via multiple P2 purinoceptors on the apical and basolateral membranes in M-1 cells.

• Journal of the Korean Chemical Society
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• v.51 no.2
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• pp.141-146
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• 2007

The present paper describes a procedure for separation, preconcentration and determination of trace amount of copper in natural water samples by using 2-mercaptobenzimidazol as the complexing agent. The proposed method is based on the surfactant aggregation formed on γ-alumina by mixing sodium dodecyl sulfate and γ-alumina in water; 2-mercaptobenzimidazol was incorporated into inner hydrophobic part of produced ad-micelles in acidic media to produce an assemble suitable for preconcentration and determination of copper ion. Optimum experimental conditions for adsorption of μg/ml levels of copper ions from aqueous solution by the adsorbent have been reported. The copper ions were quantitively adsorbed by the sorbent over the pH range of 7.1-8.0 and were quantitatively desorbed afterward by using sulfosalycilic acid as the eluent. The determination of copper was not interfered in the presence of common metal ions. The procedure was applied for analysis of river water sample. Relative standard deviation was found to be 4.91%.