• Advances in concrete construction
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• v.12 no.5
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• pp.429-437
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• 2021

In the era of building engineering the intensification of Self Compacting Concrete (SCC) is world-shattering magnetism. It has lot of rewards over ordinary concrete i.e., enrichment in production, cutback in manpower, brilliant retort to load and vibration along with improved durability. In the present study, the mechanical strength of CM-2 (SCC containing 10% of rice husk ash (RHA) as cement replacement and 600 grams of glass fibers per cubic meter) was investigated at various dosages of cement replacement by fly ash (FA) and GGBS. A total of 17 SCC mixtures including two control SCC mixtures (CM-1 and CM-2) were developed for investigating fresh and hardened properties in which, ten ternary cementitious blends of SCC by blending OPC+RHA+FA, OPC+RHA+GGBS and five quaternary cementitious blends (OPC+RHA+FA+GGBS) at different replacement dosages of FA and GGBS were developed with reference to CM-2. For constant water-cement ratio (0.42) and dosage of SP (2.5%), the addition of glass fibers (600 grams/m³) in CM-1 i.e., CM-2 shows lower workability but higher mechanical strength. While fly ash based ternary blends (OPC+RHA+FA) show better workability but lower mechanical strength as FA content increases in comparison to GGBS based ternary blends (OPC+RHA+GGBS) on increasing GGBS content. The pattern for mixtures appeared to exhibit higher workablity as that of the concentration of FA+GGBS rises in quaternary blends (OPC+RHA+FA+GGBS). A decrease in compressive strength at 7-days was noticed with an increase in the percentage of FA and GGBS as cement replacement in ternary and quaternary blended mixtures with respect to CM-2. The highest 28-days compressive strength (41.92 MPa) was observed for mix QM-3 and the lowest (33.18 MPa) for mix QM-5.

• Advances in Traditional Medicine
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• v.5 no.4
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• pp.331-335
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• 2005

The methanolic extract of Hibiscus vitifolius flowers (HVE), was evaluated for neurophamacological activities by carrying out rota rod, locomotor activity and traction performance in mice and swim endurance activity in rats in different dosages (10, 30 and 100mg/kg body weight). HVE showed a significant effect on central nervous system by increasing the time taken for rota rod, traction performance and locomotor activity while swimming time was found to be decreased when compared to normal control animals. These results suggest that HVE possess significant anxiolytic and anti depressant activity which may be attributed to the presence of flavonoid in HVE.

• Toxicological Research
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• v.13 no.1_2
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• pp.127-130
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• 1997

Acute toxicity of EPO(Erythropoietin) was investigated using rats and beagle dogs according to Established Regulation of Korean National Institute of Safety Research (1994. 4. 14). Rats and beagle dogs were injected intravenously with dosages of 20000 IU/kg, 2000 IU/kg, 200 IU/kg, 20 IU/kg and 2 IU/kg. In animals injected with EPO, there were neither dead animals nor significant changes of body weights. In addition, no differences were found between control and treated groups in clinical signs and autopsy findings. Therefore $LD_50$ of EPO was considered to be higher than 20000 IU/ kg B. W. in rats and beagle dogs.

• The Journal of the Korean dental association
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• v.51 no.3
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• pp.148-155
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• 2013

Antibiotic is one of the mainly prescribed drugs in dental office. The substantial part of all antibiotics used in dental office is given to patients without signs or symptoms of infection to prevent infections, and antibiotics became the most widely abused prescribed drugs on the basis of inappropriate indications, dosages and durations. Considering that antibiotics are one of the drugs that affect not only a single patient but also entire populations of individuals through their collective effects on microbial ecology, the importance of proper use of antimicrobial therapy can hardly be overemphasized. Therefore, the main considerations for antibiotic therapy in denial office were summarized here.

• KSBB Journal
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• v.13 no.3
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• pp.272-278
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• 1998

Cell recovery from high cell density broths of Alcaligenes eutrophus by pretreatment with aluminum-based coagulants such as aluminum sulfate, polyaluminum hydrooxide chloride silicate (PACS), and polyaluminum hydrooxide chloride (Hi-PAX) was carried out. Cells coagulated with coagulants could be successfully recovered above 95-99% by centrifugation or filtration. The optimum initial pH of fermentation broths for cell recovery was in the range of 10 to 12. Optimum coagulants dosage for cell recovery increased with increasing of cell concentrations (21-160 g/L). The optimum coagulant dosages to recover cells with more than 95% cell recovery by centrifugation for the cell concentrations ranged 21-160 g/L were as follows: aluminum sulfate, 416-1708 mg Al/L; PACS, 211-826 mg Al/L; Hi-PAX, 320-960 mg Al/L. At optimum conditions for the coagulation of cells, centrifugal forces for 95% of cell recovery were dependent on the cell concentration. The centrifugal forces at 82 g/L and 160 g/L of cell concentration were only 45${\times}$g and 1600${\times}$g, respectively.

• Biomolecules & Therapeutics
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• v.9 no.1
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• pp.46-50
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• 2001

The current study was performed to determine the acute oral toxicity of a crude extract of sanghwang mushroom (Phellinus linteus), in SD rats. 5 rats of each sex were orally treated with a single dose of extract of sanghwang mushroom at doses of 0, 500, 1,000, 2,000 mg/kg, respectively. After the treatment, clinical signs and body weight change, the food and water consumption were observed for 14 days. All animals survived during the study and did not show any clinical signs. Body weight gain showed no significant difference between the control and treated rats. However, body weight gain delayed in high dose group (2,000 mg/kg) on day 1~3 after administration. Another 5 rats of each sex were orally treated with a single dose of extract of sanghwang mushroom at dosages 4,000, 5,000 mg/kg respectively, but all animals survived during the study and did not show any clinical signs. It is suggested that LD$_{50}$ of extract of sanghwang mushroom by oral administration was estimated to be over 5,000 mg/kg in both sexes of rats.s.

• Biomolecules & Therapeutics
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• v.13 no.2
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• pp.123-126
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• 2005

The single dose toxicity of 3-methoxy-6-allylthiopyridazine (K-6) was studied with Sprague-Dawley rats. K-6 was administered orally with dosages of 4.0, 3.0, 1.5, 1.0, 0.5, 0.25 and 0.1 g/kg to the rats. We observed daily the number of death, clinical signs, body weights and gross findings. All rats (6) were dead within a day after administration when doses of 4.0and 3.0 g/kg were administered. When dose of 2.0 g/kg was administered, 2 rats among 3 rats were dead. Any significant toxicity below 1.5g/kg of K6 was not observed when the different doses of 1.5, 1.0, 0.5, 0.25 and 0.1 g/kg were administered to 6 rats respectively.

• Ocean Science Journal
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• v.41 no.4
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• pp.221-226
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• 2006

More attention has been paid to the research on decolorization of dyeing wastewater nowadays. In this study, an investigation into the decolorization of dyeing wastewater was conducted using a combination of coagulant, carboxymethyl chitosan (NOCC) and coagulant aid, polyscrylamide (PAM). The factors influencing the decolorization efficiency, such as pH value, coagulant and the dosages of coagulant, were discussed. The results showed that using PAM as coagulant aid could reach a high decolorization efficiency compared with using NOCC alone. The optimal conditions were pH 2.3, 480 mg/L for NOCC, and 4-8 mg/L for PAM. Under the optimum conditions, the rate of decolorization could achieve 99%, and the removal of chemical oxygen demand (COD) could achieve 90%. In addition, the membrane processes with chitosan/rare-earth-metals could enhance the decolorization rate of Direct Black FF to 94.7%, and Indanthren Red F3B to 98.2%, respectively.

• Biomolecules & Therapeutics
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• v.11 no.2
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• pp.109-111
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• 2003

The single oral toxicity of Jeju citrus rind pectin (Jeju pectin) was studied in Spraque-Dawley rats of both sexes. In this study, rats were administrated orally with dosages of 100, 250 and 500 mg/kg of Jeju pectin. We daily examined number of deaths, clinical signs, body weights and gross findings for 14 days after Jeju pectin administration. When we administered different doses of 100, 250 and 500 mg/kg. We found no rats died in both sex after administration. Some clinical signs (decrease locomotor activity, salivation, soft stool, prone position, lacrimation, crouching position, convulsion, ataxic gait, incontinence of mine) were also observed during the experimental period.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.3
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• pp.260-270
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• 2000

The objective of this study is to evaluate the effect of filter aids in the dual-media rapid filtration. Paper-filter tests were conducted to determine the proper dosages of coagulant and filter aid, and pilot plant tests using two dual-media filter columns were performed for a variety of filtration rates. Using a filter aid (non-ionic polymer), the maximum feasible filtration rate is 480m/day, while turbidity is less than 0.3 NTU and filter run-time is about 70 hours. It is possible to increase the filtration rate up to 360 m/day for keeping the turbidity less than 0.1 NTU. Turbidity increases for the filtration rate greater than 360m/day. In general, the quality of filtered water with a filter aid is stable, while the filter maintains a sufficient filter run-time for a maximum allowable head loss. Particularly, the initial breakthrough can be effectively controlled. The use of a filter aid may be one of the methods applicable if the turbidity of filtered water is required to be improved or if the filter breakthrough limits filter run-time.