• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.193-203
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• 1999

The corrosion of steel reinforcements in concrete is of great concern in recent years. This study is focused on the corrosion behavior of steel bars induced by internal chlorides in concrete at early ages. The main objective of this study is to determine the chloride thresholds causing depassivation and active corrosion of steel reinforcement in concrete. To examine the threshold concentration of chloride ion, the half-cell potential, chemical composition of expressed pore solutions of concrete and the rate of corosion area of the specimens were measured. Major variables include the added amount of chlorides in concrete, types of binders, and water-to-binder ration. From the present comprehensive experimental results, the factors influencing chloride-induced corrosion are investigated, and the chloride thresholds causing active corrosion of steel bars are proposed. The present study will enable to specify the realistic chloride limit in concrete which can be used in the future technical specification.

• The Journal of Internal Korean Medicine
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• v.28 no.2
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• pp.217-229
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• 2007

Objectives : The aim of this experimental study was to investigate the effects of Bojangjisa-tang on anticatharsis by using mice and Guinea pigs. Methods : We observed the actions on gastrointestinal smooth muscles, on the transportability of small and large intestines and on diarrhea induced by castor oil, philocarpine, and barium chloride. Results : Bojangjisa-tang showed alleviation of the contraction of gastrointestinal smooth muscles induced by acetylcholine chloride and barium chloride. The transportability of the large intestine was constrained by Bojangjisa-tang, which also showed substantial anti-cathartic effects on diarrhea induced by castor oil, philocarpine and barium chloride. Conclusion : These results demostrate that Bojangjisa-tang has advantageous effects on drug-induced diarrhea and will contribute to the development of diarrhea treatment through further related studies.

• The Journal of Korean Medicine
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• v.18 no.2
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• pp.82-96
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• 1997

In order to investigate the effect of Daewhajungeum on the isolated organs, gastrointestinal tract and C.N.S., some kinds of experiments using mice and rats were done. The results were as follows; 1. Daewhajungeum showed the inhibitory effect on the smooth muscle contraction of the isolated ileum and colon induced by acethylchorine chloride and barium chloride in mice. 2. Daewhajungeum showed inhibitory effect on the contraction of the fundus-strip induced by acethylchorine chloride and barium chloride in rats. 3. The preventive effect on pyloric ulcer, indomethacin induced ulcer and ethanol-HCl induced ulcer of mice was recognized. 4. The effect on the acidity of gastric juice was suppressed, but the effect on the pepsin output was not recognized. 5. The transport ability of small and large intestine was significantly decressed. 6. The analgesic effect and the sedative effect were recognized so that the effect of the C.N.S was suggested.

• The Journal of Internal Korean Medicine
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• v.18 no.1
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• pp.242-254
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• 1997

An experimental studies were done to investigate the spontaneous movements to the isolated ileum with the liquid extracts of Wahngkigunchunghapleechungtang. Then the effects of isolated ileum, pylorus-ligated and indomethacin-induced ulcer, gastric juice secretion, and transport abilities of the small and large intestine were studied. The following results have been obtained; 1. Wahngkigunchunghapleechungtang showed to have an inhibitory effects on the smooth muscle contraction of the isolated ileum by acetylcholine chloride and barium chloride. 2. Wahngkigunchunghapleechungtang showed to have an inhibitory effect on the contraction of the gastric fundus-strip by acetylcholine chloride and barium chloride. 3. The preventive effects were not recognized on the pylorus-ligated ulcer, by administration of Wahngkigunchunghapleechungtang. 4. The preventive effects were recognized on the indomethacin-induced ulcer by administration of Wahngkigunchunghapleechungtang. 5. The Inhibitory effects on the secretion gastric juice, free & total acidity, and pepsin output were recognized by administration of Wahngkigunchunghapleechungtang. 6. The transport abilities in the small intestine were not recognized by administration of Wahngkigunchunghapleechungtang. 7. The transport abilities in the large intestine were increased by administration of Wahngkigunchunghapleechungtang. According to the above results, it is considered that the experimental effects of Wahngkigunchunghapleechungtang has correspond to the oriental medical literatures.

• The Journal of Internal Korean Medicine
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• v.27 no.2
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• pp.459-470
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• 2006

Objectives: The aim of this experimental study is to investigate the effects of MYRISTICAE SEMEN, GRANATI PERICARPIUM and ALPINIAE KATSUMADAI SEMEN on the anticatharsis by using mice and Guinea pigs. Methods : We evaluated the effect of herbs on the extracted organs contraction, the barium sulfate transport, and the anticathartic action induced by acetylcholine chloride, barium chloride, histamine chloride, neostigmine, castor oil, pilocarpine in the ileums, large intestines, small intestines of animals. Results : In the extracted organs, all herbs showed concentration-dependent inhibitory effect on the constriction of extracted ileum. The transport of barium sulfate in the large and small intestine was increased in comparing with the control group. And every three herbs showed the anticathartic action. Conclusions : These results demonstrate that MYRISTICAE SEMEN, GRANATI PERICARPIUM and ALPINIAE KATSUMADAI SEMEN extracts have an advantageous effects on diarrhea induced by drugs and will contribute to the development of diarrhea treatment through further related studies.

• Journal of the Korean Magnetic Resonance Society
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• v.11 no.2
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• pp.115-121
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• 2007

A new quantitative analysis of chloride by the HERETIC NMR method which does not need internal or external references was described. The results showed that the use of HERETIC peak corresponding $500\;{\mu}g/mL$ of chloride calibration showed less than 4 % standard deviations from 50 to $5000\;{\mu}g/mL$ range of chloride concentrations.

• Journal of the Korean Society of Safety
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• v.31 no.4
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• pp.75-81
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• 2016

This study presents the effect of urea and sulfur admixture on compressive strength, chloride diffusion coefficient, and internal void distribution of concrete. Compressive strength of concretes with urea admixture by 5% increased by 5% relative to Control. However, that of concretes with urea admixture over 10% decreased. Chloride diffusion coefficient of concrete with urea and sulfur admixture decreased by 40% relative to Control. Additionally, the volume of internal void of concrete with urea and sulfur admixture decreased by 20% relative to Control. Therefore, it can be mentioned from test results that the use of adequate urea and sulfur admixture improves the mechanical properties and durability of concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.150-151
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• 2013

Recently, the internal space organization of the building changes to the frame construction and flat slab construction in the wall type structure. And the use of light weight panel changing the internal joint use easily is increased. Therefore, in this research, the length change characteristic that the magnesium chloride addition rate reaches to the magnesium curing body tries to be studied. It could confirm according to the length change specific result that the magnesium chloride amount of addition reaches to the magnesium oxide curing body to expand. And the thing described below was the large-scale expansion the magnesium oxide addition rate 60%. And it showed up as 50, 40, 30, 20, and order of 10s (%). It could look at to form the hydrate of the SEM picture result needle-shaped of the Hardened.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.50-59
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• 2020

Superabsorbent Polymer (SAP) expands inside concrete by absorbing water and contracts as it discharges water. Through this process, concrete can achieve the internal curing effect, but the space occupied by the expanded SAP remains as a void. In this study, the effects of SAP internal curing and voids were evaluated by evaluating the fundamental properties and chloride penetration resistance of SAP mixed concrete. Also, to evaluate the internal curing effect by SAP, the tests were carried out under water and sealed curing conditions, respectively. From the result, the compressive strength of water curing did not differ significantly according to the mixing ratio of SAP. In the case of sealed curing, however, the compressive strength tended to increase as the mixing ratio of SAP increased. The internal curing effect of sealed curing was considered to have influenced the increase in compressive strength. In the case of the chloride diffusion coefficient, the diffusion coefficient tended to decrease as the mixing ratio of SAP increased. In particular, as the sealed curing is applied, the chloride penetration resistance is further improved due to internal curing effect. If the curing conditions are different, it is considered inappropriate to estimate the chloride penetration resistance by the surface electrical resistivity.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.4 no.1
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• pp.1-16
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• 1998

In order to investigate the effect of Bujaleejungtang, by means of oral medication to rats and mice, to isolated intestine and stomach, and the effect to pyloric ulcer, indomethacin-induced ulcer, secretion of gastric juice, and to transport ability of intestine content were studied as the action to G-I tract. The effect to normal rats and resperpine-treated rats were studied as the action to thermo-regulation. The results were as follows: 1. Bujaleejungtang showed the inhibitory effect on the smooth muscle contraction induced by acethylcholine chloride and barium chloride in the isolated mice ileum. 2. Bujaleejungtang showed inhibitory effect on the contraction induced by acetylcholine chloride and barium chloride in the rat fundus-strip. 3. Inhibitory effect of Bujaleejungtang on pyloric ulcer, indomethacin-induced gastric ulcer in rats was statistical recognized(p<0.05). 4. No inhibitory effect of Bujaleejungtang on gastric juice secretion in Shay rats was recognized. 5. Inhibitory effect of Bujaleejungtang on gastric free acidity and total acidity in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg) (p<0.001). 6. Inhibitory effect of Bujaleejungtang on pepsin output in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.001). 7. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the small intestine of mice was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05). 8. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the large intestine of mice was recognized(p<0.05). 9. Inhibitory effect of Bujaleejungtang on rectal temperature in normal rats was recognized. 10. Inhibitory effect of Bujaleejungtang on rectal temperature in reserpine-treated rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05).