• The Journal of Engineering Geology
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• v.31 no.1
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• pp.67-81
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• 2021

Grouting is used for reinforcement and waterproofing of soft ground to increase its bearing capacity, reduce the impacts of rising or lowering groundwater levels, and reduce subsidence due to vibration and general causes. This study investigated the enhancement of grout strength and hardening time by the addition of reinforcing fibers, and the development of non-cement grouting materials from blast furnace slag. An experiment was performed to measure the increase in grout strength resulting from the addition of 0.5% increments of aramid and carbon reinforcing fibers. The results show that the uniaxial compressive strength of grout increases with increasing content of reinforcing fiber. Comparison of three admixtures of finely powdered blast furnace slag and 10%, 20%, and 30% calcium hydroxide stimulating agent showed that the uniaxial compressive strength of the mixture increases with increasing content of alkaline stimulant; however, the strength was lower than for 100% pure cement. The reaction of calcium hydroxide with blast furnace slag powder, which increases the strength of the grout, is more effective if injected as a solution rather than a powder.

• KSBB Journal
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• v.18 no.1
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• pp.55-61
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• 2003

To isolate and purify the antimicrobial and antitumor agents in Xanthium strumarium L. hydrothermal extract. The crude extract was extracted in ether or ethylacetate under neutral, acidic, and alkali conditions. The antimicrobial activity of each extract was tested against 16 strains of bacteria, 2 strains of yeast, and 2 strains of fungus. The ether neutral extract (XE-N) exhibited the strongest growth inhibition upon the 8 strains of gram-positive bacteria, 6 strains of gram-negative bacteria and Cryptococcus neoformans. Fluorescein diacetate (FDA) testing of XE-N and XEA-N showed growth inhibition of the 3 strains of E. coli, S. aureus and C. albicans even at 30 ng/mL, with the exception of p. aeruginosa. XE-N-S1 and XE-N-S3 from neutral ether extract (XE-N), XE-N-S3 from the acidic ether extract (XE-A), and XEA-N-S1 from ethylacetate (XEA-N) were purified as antimicrobial and antitumor agents. However all purified compounds decomposed with the exception of XE-N-S1. The results upon the antitumor activities of the crude extract and of its purified compounds, showed that XE-N-S1 had the best antitumor activity against HeLa cells. In terms of antitumor activity against HepG2 cells, XE-N-S1 and XE-N-S3 were superior, and against HT29 cells XE-N and XE-N-Sl were good, against Saos2, NCI H522, NCI H1703, Clone M3 cells XE-N-51 was very good, and against LN CAP cells XE-N-S3 was the best. Comparing of cellular toxicities various extracts and purified compounds with the existing antitumor agents, XE-A, XEA-A and XEA-B had the lowest toxicity, and XE-B had a lower toxicity than etoposide. XE-N-S1 and XE-N-S3 showed higher toxicities than etoposide, and the toxicity of XE-A-S3 was higher than that of etoposide, and lower than that of csplatin.

• Applied Biological Chemistry
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• v.9
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• pp.71-81
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• 1968

Defatted rice bran is mixed with diluted acid solution, the mixture is agitated some hrs. at constant temparature. After the mixture is filtered, thus filtrate is obtained. This filtrate is phytin extract solution. (Test-1) The alkali is added to this filtrate and filtered out, then the precipitation of phytin is obtained. (Test-2) At the test-1, the effect of kind of acid, conc. of acid, amount of extract sol'n., time of extraction, temp. of extraction, to the extract amount of phytin is tested. Consequently, the following facts are known. 1. Amount of phytin extract is greater HCI extraction than $H_{2}SO_4$ extraction. 2. At 0.3% HCI, the amount of phytin extract is greatest of all HCl extraction. 3. The sufficient amount of acid solution is 8-10 times of amount of defatted rice bran. 4. The time of extraction at room temperature is sufficient 8-12 hrs. 5. When extract temperature is $20-30^{\circ}C$, the amount of phytin extraction is greater of all temp. 6, When defatted rice bran 20 g is shanken with 160 ml of 0.3% HCl for 10 hr. at room temp., in this case the amount of phytin extract is 11.34% of defatted rice bran, it is 93% of theoretical yield. At the test-2 the effect of kind of precipitation agent, degree of nutralization to the amount of phytin prcipitation is tested. 1. Degree of nut. is best at pH 6.8-7.0. 2. When use of $Ca(OH)_2$ the amount of phytin precipitation is more than use of KOH, NaOH, or $NH_{4}OH$. 3. At pH 6.0-7.2, the solubility of phytin is followed. K-phytate > $NH_{4}-phytate$ > Na-phytate > Ca-phytate 4. When phytin extract solution is nutralized with $Ca(OH)_2$ to pH 7.0, the amount of phytin precipitation is 94.78% of theoretical yield.

• Clean Technology
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• v.19 no.3
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• pp.264-271
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• 2013

In this study, we optimized the removal condition of contaminants attached on the scrap surface to recycle the scrap generated from the Zr alloy tube manufacturing process back to the nuclear grade. The main contaminant is remnant of watersoluble cooling lubricant that is used in the pilgering manufacture during the tube production, and it is assumed to be compressed and carbonized on the surface of tube. Zirlo alloy tube of ${\phi}9.50mm$, which has high occurrence frequency of scrap, was selected as the object to be cleaned, and cleaning abilities of reagents were evaluated by measuring the characteristics of contaminants remained and by analyzing the surface of the tube after cleaning process. For evaluation of each cleaning agent, we selected two types of sodium hydroxide series and three types of potassium hydroxide series. Furthermore, to confirm dependence on tempe-rature and ultrasonic intensities, cleaning at the room temperature, $40^{\circ}C$, and $60^{\circ}C$ was conducted, and results showed that higher the cleaning temperature and higher the ultrasonic intensity, better the cleaning effect. As a result of the bare-eye inspection, while the use of sodium hydroxide provided satisfactory condition on the tube surface, the use of potassium hydroxide series provided satisfactory condition on the tube surface only when the ultrasonic intensity was over 120 W. In the cleaning effect analysis using the gravimetric method, cleaning efficiency of sodium hydroxide series was as high as 97.6% ($60^{\circ}C$, 120 W), but since the tube surface condition was poor after the use of potassium hydroxide, the gravimetric method was not appropriate. In the analytical result of surface contaminants on the tube surface, C, O, Ca, and Zr were detected, and mainly C and O dominated the proportion of contaminants. It was also found that the degree of cleaning on the tube affected the componential ratio of C and O; if the degree of cleaning is high, or if cleaning is well-conducted, the proportion of C is decreased, and the proportion of O is increased. Based on these results, optimal cleaning for application in the industry can be expected by categorizing cleaning process into three steps of Alkali cleaning, Rinsing, and Drying and by adjusting cleaning parameters in each step.

• Journal of Preventive Medicine and Public Health
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• v.29 no.1 s.52
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• pp.1-14
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• 1996

To evaluate the health risk of the workplace environment of a general hospital toward the hospital workers, a questionnaire survey on the perception of risk at the workplace environment and environmental measurements at 27 locations with 240 workers in the hospital were made from October 25th, 1993 to October 30th, 1994. The results were as follows ; 1. By the environmental measurements, 86 workers(36%) were found to be exposed to poor or harmful degree of general illumination, 193 workers(80%) were exposed to poor or harmful local illumination, 34 workers(14%) were exposed to poor or harmful degree of thermal condition and 180 workers(75%) were exposed to poor or harmful noise level, but nobody was exposed to poor or harmful dust and toluene concentration. Also nobody was exposed to poor or harmful level of radiation or anticancer/antibiotic agents. 2. The subjective perceptions on the environmental conditions felt by the workers were different from the objective findings by the environmental measurements. The workers underscored the poor illumination state and overscored the dust concentrations. Also workers oversensitized about the thermal condition, the noise level, the radiation level, the toluene concentration and anticancer/antibiotic agents 3. The sources of noise were the dialogue(179 workers) and the office instruments(131 workers). The sources of dust came from the clothes(108 workers) and the building materials(79 workers). 4. The questionnaire survey showed that the 28 workers were exposed to poor or harmful level of the antibiotics, 10 workers to alkali or acid and 6 workers to drug dust in the pharmacy but the above findings could not be proved by the environmental measurements.