• Proceedings of the Plant Resources Society of Korea Conference
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• 2012.05a
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• pp.18-18
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• 2012

Antioxidant is an important role to protect the human body against damage by reactive oxygen species. However, the excessive intake of such antioxidant is known to cause a serious poisonous influence on one's liver, lungs and circulating system. Therefore, it is necessary to develop a safe natural antioxidant. For the purpose of developing natural antioxidant and antibacterial, the antioxidant activity and antibacterial effects of various extract solvents from Artichoke (Cynara Scolymus L.) leaf were determined. In this study, the extracts of Artichoke leaf dried from solvent extraction were examined by means of DPPH free radical scavenging activity and ABTS free radical scavenging activity. The effect of free radical scavenging compared with $\alpha$-tocopherol and L-ascorbic acid. In Artichoke leaf extract, evaluated by using DPPH and ABTS showed that the highest antioxidant activities were found to be in methanol extracts from DPPH radical ($IC_{50}$: $20.06{\mu}g\;mL^{-1}$), ABTS radical ($IC_{50}$: $16.01{\mu}g\;mL^{-1}$) and followed by ethanol > methyl chloride > ethyl acetate > n-Hexane. By using disc diffusion method, the antibacterial activity showed that the Artichoke leaf extract was found to be most effective against all of the tested organisms and the methyl chloride extract showed the most significant antibacterial effect against all of tests among 5 solvents extract, followed by ethyl acetate > n-Hexane > ethanol > methanol. As a result, optimal in antioxidant activity for Artichoke (Cynara Scolymus L.) leaf is methanol extract and for antibacterial effect is Methyl Chloride extract.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.6
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• pp.607-615
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• 2009

Analysis of chloride penetration into concrete is performed considering the repeated wetting and drying conditions of tidal zone, by means of the developed finite element program which enables the diffusion-convection analysis to be conducted. Heat conduction and moisture diffusion are also included in the finite element analysis program in order that their effects to chloride penetration may be considered. For the efficiency of calculation, the analyses of temperature, relative humidity and free chloride concentration are conducted successively in that order, by treating the convection of chloride due to moisture diffusion as an source or sink term. By comparing the analysis result from finite element analysis, where main variable is a wetting and drying period, with the chloride profiles from ACI Life-365 method, it is shown that the Life-365 method gives an accurate result for the submerged zone but does not consider the differences of wetting and drying period. To obtain an accurate chloride profile in the tidal zone, it is confirmed that the diffusion-convection finite element analysis should be applied.

• Journal of Acupuncture Research
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• v.15 no.2
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• pp.255-277
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• 1998

The aim of this experiment was to investigate the effects of Aqua-Acupuncture of Yukmijiwangtang(六味地黃湯) and Palmijihwang-tang(八味地黃湯) water extracts applied at the meridian points BL 23(賢兪) and GV 4(命門) to test the renal function in normal rats. The results obtained were as follows; 1. Among the effects of Aqua-Acupuncture of Yukmijihwangtang water extract at the merdian point BL 23 group, there were significant changes in water balance and urine volume over a 1 week period; Both decreasing and decreasing trends were exihibited. Urinary excretion of sodium and free water clearance changed significantly over a 2 week period; Both decreasing and increasing trends were exihibited, Urinary excretion of potassium, chloride and creatinine, plasma renin activity, plasma levels of aldosterone and atrial natriuretic peptide showed no significant differences compared to the contral group. 2. Among the effects of Aqua-Acupuncture of Palmljihwangtang water extract at the merdian point BL 23 group, there were significant changes in water balance and free water clearance over a 2 week period; a decreasing trend. Urinary excretion of creatinine changed significantly over a 2 week period; an increasing trend. Urinary excretion of chloride changed significantly over 1 week period; an increasing trend. The plasma levels of atrial natriuretic peptide changed significantly over 1 and 2 week period; an increasing trend. Urine volume, urinary excretion of sodium and pottasium, plasma renin activity and plasma level of aldosterone showed no significant differences compared to the control group. 3. Among the effects of Aqua-Acupuncture of Yukmijihwangtang water extract at the meridian point GV 4 group, there was significant decrease in water balance over a 2 week period; there was significant decrease in urine volwne and urinary excretion of sodium and creatinine over a 1 week period, followed by an increasing trend after 2 weeks. Urinary excretion of free water clearance demonstrated significant changes over both 1 and 2 week period; both increasing and decreasing trends were exihibited. Urinary excretion of chloride and plasma levels of aldosterone increased significantly over 1 and 2 week period. Plasma levels of atrial natriuretic peptide also decreased significantly. Plasma renin activity showed no significant differences compared to the control group. 4. Among the effects of Aqua-Acupuncture of Palmijihwangtang water extract at the meridian point GV 4 group, water balance and urinary excretion of chloride, plasma levels of aldosterone decreased significantly over both 1 and 2 week period. Urine volume and urinary excretion of pottasium decreased significantly. Urinary excretion of creatinine and urinary excretion of sodium changed significantly over both 1 and 2 week period. Urinary excretion of free water clearance, plasma renin activity and plasma level of atrial natriuretic peptide showed no significant differences compared to the control group. Seeing these results, I come to know that the effects Aqua-Acupuncture of Yukmijihwangtang and Palmijihwangtang water extracts at the meridian point BL 23 and GV 4 have affected the renal function differently. Seeing the results that BL 23 is a meridian point for Aqua-Acupuncture directly related to the kidney, I think, we can use Aqua-Acupuncture of Yuk-mijihwangtang and Palmijihwangtang water extracts to prevent and to treat the diseases related to kidney.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.236-245
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• 2021

It is very important for structure designer to understand the service life variation since a wide range of service life is evaluated with changing exposure conditions and design parameters. Recently, for zero-carbon, waste plastic has been used for fuel for clinker production and this yields increase in chloride content in cement. This study is for evaluation of changing service life in the concrete with increasing initial chloride content due to usage of plastic-SRF(Solid Refuse Fuel) considering various exposure conditions and design parameters. For this, 4 levels of initial chloride content were assumed, and the service life was assessed using LIFE 365 program considering various environmental conditions including 3 levels of surface chloride content. As for analysis parameters, critical/initial chloride content, blast furnace slag powder replacement ratio, W/B(Water to Binder) ratio, cover depth, and unit mass for binder are adopted. Service life decreases with increasing initial chloride content and a significant reduction of service life is not evaluated permitting up to 1,000ppm of initial chloride content. With increasing slag replacement ratio, a longer service life can be secured since blast furnace slag powder has the effect of reducing the diffusion of external chloride ions and fixing the free chloride. It is thought that increasing initial chloride content up to European standard is helpful for enhancing sustainability and reducing carbon emission. Though the reduction in service life due to an increase in the initial chloride content is not significant in slag-concrete with low surface chloride content, careful consideration for mixing design should be paid for the exposure environment with high surface chloride content.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.499-504
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• 2012

The specific rates of sovolysis of 4-methylthiophene-2-carbonyl chloride (1) have been determined in 26 pure and binary solvents at $25.0^{\circ}C$. Product selectivities are reported for solvolyses of 1 in aqueous ethanol and methanol binary mixtures. Comparison of the specific rates of solvolyses of 1 with those for p-methoxybenzoyl chloride (2) in terms of linear free energy relationships (LFER) are helpful in mechanistic considerations, as is also treatment in terms of the extended Grunwald-Winstein equation. It is proposed that the solvolyses of 1 in binary aqueous solvent mixtures proceed through an SN1 and/or ionization (I) pathway rather than through an associative $S_N2$ and/or addition-elimination (A-E) pathway.

• Korean Journal of Microbiology
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• v.26 no.2
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• pp.93-100
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• 1988

In order to understand the regulation of glutamate dehydrogenase(GDH) synthesis in Brevibacterium flavum, we have isolated a mutant lacking NADP-linked GDH activity by ethlmethane sulfonate treatment. The $gdh^-$ mutant was grown on the minimal plate with 1mM ammonium chloride and not that with 300mM ammonium chloride. The cell-free extracts from $gdh^-$ mutant and prototroph were also examined with glutamine synthetase(GS) and glutamate synthase (GOGAT) production by niteogen sources. The growth of $gdh^-$ mutant in presence of 20mM ammonium chloride means that GOGAT synthesis is sufficient to allow growth in this condition. GS production of $gdh^-$ mutant as well as parental strain was induced by 1mM urea and ammonium tartrate, but it was repressed by higher concentration of ammonia, and also induced by 20mM to 50mM glutamate as a substrate. It was special attention that GOGAT synthesis from $gdh^-$ strain was more repressed by higher concentration of ammonia than prototroph as described in E. coli system.

• Biomedical Science Letters
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• v.12 no.4
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• pp.451-455
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• 2006

It is demonstrated that inorganic mercury has cytotoxic effect on glial cells. Recently, oxygen radicals is involved in methylmercuric chloride (MMC)-induced cytotoxicity. But, the toxic mechanism of MMC is left unknown. The purpose of this study was to examine the cytotoxicity of MMC on $C_6$ glioma cells. The cytotoxicy was measured by cell viability using XTT assay in $C_6$ glioma cells. Colorimetric assay is regarded as a very sensitive screening method for the determination of the cell viability on various agents. In this study, MMC decreased cell viability according to the dose- and time dependent manners after $C_6$ glioma cells were grown with various concentrations of MMC for 48 hours. In the protective effect of allopurinol on MMC-induced cytotoxicity, allopurinol was effective in the prevention of MMC-induced cytotoxicity in these cultures. These results suggest that MMC has highly cytotoxic effect on $C_6$ glioma cells by the decrease of cell viavility, and free radical scavenger such as allopurinol was effective on organic mercury-induced cytotoxicity in these cultures.

• Biomolecules & Therapeutics
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• v.7 no.2
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• pp.164-169
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• 1999

The synthesis and antimicrobial activity of N-substituted glycol derivatives of Norfloxacin were described. Norfloxacin was treated with chloroacetyl chloride to yield chloroacetyl norfloxacin (1). This compounds was reacted with alkyldiamines to afford bivalent ligand quinolone carboxylic acids (2-6), which was added to pivaloyloxymethyl chloride to give bivalent ligand pivaloyloxymethyl quinolone carboxylates (7-11). Chloroacetyl norfloxacin (1) treated with alkylamines to obtain monovalent ligand quinolone carboxylic acids (12-15), which was reacted with pivaloyloxymethyl chloride to get monovalent ligand pivaloyloxymethyl quinolone carboxylates (16-19). Free carboxylic quinolones (2-6, 12-15) showed little stronger activities to their pivaloyloxymethyl esters (7-11, 16-19). In monovalent ligand quinolone analogues, longer a1kyl chain com-pounds showed stronger activities than shorter one.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3218-3222
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• 2013

The aminolyses, anilinolysis and pyridinolysis, of bis(2-oxo-3-oxazolidinyl) phosphinic chloride (1) have been kinetically investigated in acetonitrile at 55.0 and $35.0^{\circ}C$, respectively. For the reactions of 1 with substituted anilines and deuterated anilines, a concerted SN2 mechanism is proposed based on the selectivity parameters and activation parameters. The deuterium kinetic isotope effects ($k_H/k_D$) invariably increase from secondary inverse to primary normal as the aniline becomes more basic, rationalized by the transition state variation from a backside to a frontside attack. For the pyridinolysis of 1, the authors propose a stepwise mechanism with a rate-limiting step change from bond breaking for more basic pyridines to bond formation for less basic pyridines based on the selectivity parameters and activation parameters. Biphasic concave upward free energy relationship with X is ascribed to a change in the attacking direction of the nucleophile from a frontside attack with more basic pyridines to a backside attack with less basic pyridines.

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.261-268
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• 2004

Corrosion of reinforcement is the main cause of damage and early failure of reinforced concrete structures. The corrosion is mainly progressed by the chloride ingress. In this paper, an experimental study is executed to investigate the effect of concrete properties and testing methods on the coefficients of chloride diffusion. Also, it is surveyed the relationship between total chloride and free chloride in concrete. According to this experiment results, W/C ratio and testing method affect chloride diffusion coefficient of concrete. As W/C ratio is increased, diffusion coefficient in concrete is also increased. Diffusion coefficient obtained by each testing method show the different values, respectively. The model equation of diffusion coefficient with W/C ratio is proposed.