• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.5 no.1
• /
• pp.104-118
• /
• 1995

This study was performed to evaluate factors affecting desorption of organic solvents collected on charcoal tube and to find out the optimum condition. Desorption efficiency for polar analytes was improved when several polar desorption solvents such as methanol, dimethylformamide(DMF), 2-(2-butoxyethoxy)ethanol were added to carbon disulfide($CS_2$). The best improvement was achieved when 10% dimethylformamide(DMF) in $CS_2$ was used as desorption solvent. During storage of polar analytes, recovery was greatly reduced. Especially, the recovery of cyclohexanone was decreased to 18.1 % after a month storage at $34^{\circ}C$. After two weeks storage, recovery of polar analytes was sharply decreased. Water adsorbed on charcoal interfered the recovery of polar analytes but didn't interfere that one of nonpolar solvent, toluene. When 10% DMF in $CS_2$ was used as desorption solvent, the effect of water on recovery was decreased, comparing with Desorption efficiency increased when analyte loading increased, and usage of 10% DMF in $CS_2$ decreased the loading effect. Increasing volume of desorption solvent was not effective to improve desorption efficiency of analytes when 10% DMF was used. Continuous shaking and sonication is not helpful to increase the desorption efficiency of analytes except cyclohexanone using 10% DMF. When silica gel used as adsorbent, methanol was better desorbent than dimethylsulfoxide. Analytes adsorbed on silica gel showed high recovery in low concentration and less affected by humidity. On the basis of this study, the following conclusions have been drawn. To improve the recovery of polar organic materials in air samples, it is necessary to analyze samples as soon as possible after they were collected. Otherwise, samples must be stored at low temperature. Using two components of desorption solvents, such as 10% DMF in $CS_2$, the effects of loading and humidity decreased for polar analytes such as methyl ethyl ketone and methyl isobutyl ketone. When work place has high humidity with low concentration of polar organic solvents, silica gel can be used as adsorbent, because it produces quantitative recovery for polar analytes at this condition. But it should be noted that high humidity makes breakthrough easy in silica gel samples.

• Korean Journal of Clinical Laboratory Science
• /
• v.51 no.2
• /
• pp.177-184
• /
• 2019

Mycobacteria grow slowly. Therefore, a solid medium should be used for eight weeks and a liquid medium for six weeks. The purpose of this study was to find the growth factors that can grow Mycobacterium rapidly and to help develop a solid medium for rapid identification. Three types of Mycobacterium growth factors were evaluated with 10 Mycobacteria by adding activated charcoal, defibrinated sheep blood, and L-ascorbic acid to $Difco^{TM}$ Mycobacteria 7H11 agar (Becton, Dickinson and Company, Sparks, MD, USA). The time to detection and the distinguishability of a colony were compared with that of the current method. In the rapidly growing Mycobacterium, the difference in detection time between the new media and conventional media confirmed that the new media was faster. M. kansasii and M. intracelluare grew faster in 7H11 C than in 7H11 medium. MTB grew faster than the other media in 7H11 C. This study confirmed that the two growth factors affect fast-growing Mycobacteria and slow-growing Mycobacteria. 7H11 C showed better distinguishability than the conventional media in all 10 Mycobacterium due to the color contrast. In particular, when the MTB was grown, the size of the colonies was larger than with other media, so visualization was easy.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.34 no.1
• /
• pp.67-76
• /
• 2024

Objectives: Direct reading instruments (DRIs) are widely used by industrial hygienists and other experts for preliminary survey and identifying source locations in many industrial fields. Photoionization detectors (PIDs), which are a form of hand-held portable DRIs, have been used for a variety of airborne vaporized chemicals, especially evaporated hydrocarbon solvents. The benefits of PIDs are high sensitivity between each chemical, competitive price, and portability. With the goal of increasing the accuracy of logged PID concentrations, previous studies have performed tests for the assessment of single chemical compounds, not mixtures. The purpose of this preliminary study was to measure mixtures with a PID and charcoal tube at the same time and compare the accuracy between them. Methods: A chamber test was implemented with different mixtures of hydrocarbon chemicals (acetone, isopropyl alcohol, toluene, m-xylene) and levels in the range of 14 to 864 ppm. Three PIDs and charcoal tubes were connected to the chamber and measured the chemical mixtures simultaneously. A comparison of accuracy and the PID group of concentrations with manufacture correction factor (M_CF) and field correction factor (F_CF) applied was performed. Results: The accuracy of the PID concentrations data-logged from the PID did not meet the accuracy criteria except for the mixture level B and C logged from PID No. 2, which was 18% of all tests for meeting accuracy criteria. The mean and standard deviation (SD) of concentration (ppm) of the charcoal tube followed by each mixtures' level were 10.37±0.26, 155.33±5.28, 300.80±11.65, and 774.93±22.65, respectively. When applying F_CF into the PID concentrations, the accuracy increased by nearly 82%. However, in the case of M_CF, none met the accuracy criterion. Between the PID there were differences of logged concentrations. Conclusions: In this preliminary study, the concentration of a logged PID with F_CF applied was a better way to increase accuracy compared to applying M_CF. We suggest that additional research is necessary to consider environmental factors such as temperature and humidity.

• Herbal Formula Science
• /
• v.32 no.3
• /
• pp.297-310
• /
• 2024

Objective : This study was conducted to investigate the anti-inflammatory and laxative effects of Polycan in TNF-α-treated HT-29 intestinal epithelial cells and loperamide-induced constipation in vivo models, respectively. Methods : To evaluate the anti-inflammatory effects of Polycan, HT-29 cells were treated with TNF-α in the presence or absence of Polycan. IL-8 production was measured by enzyme-linked immunosorbent assay (ELISA). MAPK phosphorylation, nuclear translocation of NF-κB, and phosphorylation of IκB were assessed by Western blot analysis. To investigate the laxative effects of Polycan, 6-week-old SD rats (8 female rats per group) were orally administered Polycan or Chicory Fiber as a positive control for 4 weeks, and constipation was induced with loperamide treatment for 10 days before sacrifice. One day before sacrifice, a charcoal meal was administered to evaluate intestinal transit times. The periodically collected feces were used to assess the number of fecal pellets and fecal water content. Results : Polycan inhibited TNF-α-induced IL-8 expression in dose-dependent manner. Furthermore, Polycan suppressed TNF-α-induced phosphorylation of MAPKs (ERK1/2, p38 and JNK), degradation of Iκ-Bα and nuclear translocation of NF-κB. In an in vivo constipation model, the number of fecal pellets per food intake was significantly increased in rats administered with Polycan, both 1 day and 7 days after loperamide treatment. The water content of fecal pellets was restored in the Polycan groups starting 7 days after loperamide treatment. In addition, Polycan intake significantly enhanced the gastrointestinal transit ratio of a charcoal meal but reduced the number of intestinal fecal pellets. Conclusions : These results suggest that Polycan suppressed TNF-α-induced inflammation by blocking both the MAPK and NF-κB pathways in HT-29 cells. Additionally, in a loperamide-induced constipation model, Polycan showed clear laxative effects by increasing the number of fecal pellets, fecal water content, and intestinal transit ratio of a charcoal meal.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 1999.10a
• /
• pp.397-398
• /
• 1999

활성탄은 1,000m$^2$/g 이상의 큰 표면적을 가지며, 이것을 활용하여 공업적인 용도로 예부터 탈취제와 같은 흡착제로서 이용되고 있다. 최근에는 생활 수준의 향상으로 인해 악취에 대해 민감해져서 악취 제거제로서 활성탄의 사용량은 갈수록 늘어나고 있는 추세이다. 특히 우리나라의 경우 공업단지 주변에서의 악취에 대한 민원이 급증함으로써 여러 악취발생업체에서 악취 제거장치로서 활성탄을 이용하는 곳이 많아지고 있다.(중략)

• Nuclear Engineering and Technology
• /
• v.51 no.2
• /
• pp.641-645
• /
• 2019

Experimental equipment for studying the sorption properties of iodine sorbents using radioactive methyliodide has been developed. The sorption capacity index ${\alpha}$ is proposed as a criterion parameter for assessing the quality of impregnated activated charcoals. It was found that this parameter does not depend on the dynamic conditions during the sorbent test. It was shown that values of the sorption capacity index allow to recommend iodine sorbents for industrial gas cleaning processes.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.39 no.2 s.120
• /
• pp.68-77
• /
• 2007

It is necessary to recognize philosophical and scientific depth, contained in traditional culture in a correct fashion, in order to succeed and develop our excellent traditional culture. Some studies on storage, circulation, and package design of traditional food will multiple the added value of traditional culture. So this research was carried out for making packing cases of kinds of Korean dried confectionery using Hanji by traditional manufacturing method, Hanji textile, charcoal Hanji and jade Hanji, and for developing environmental-friendly Korean dried confectionery package as more luxurious packaging papers by putting an exterior design on the surface. The results measured physical properties, air permeability and anti-mold activity of Hanji, and designing Korean dried confectionery are as follows. The physical properties and air permeability used to manufacture Korean dried confectionery package, turned out to be no affection to the food packaging Hanji. In order to avoid the monotonousness of Korean dried confectionery package, it was designed with Hanji textile together with elegant traditional pattern. It is estimated to increase the value of Korean dried food and to make the anti-mold activity of Hanji added charcoal and jade effective. In conclusion, by developing individual properties of traditional food and proper packaging paper as well as packaging design according to circulating situation, it is considered that the taste and the fancy can be maximized. After all, by applying excellent traits contained in our race's culture, it is possible to develop the package cases into competitive ones. And it would be able to increase utilization of Hanji. Namely, production of high quality traditional food package with Hanji is expected for new valuable industry of Hanji.

• Resources Recycling
• /
• v.17 no.6
• /
• pp.68-78
• /
• 2008

Using a Pinus koraiensis and Pinus rigida which are normally being discarded in South Korea, optimal conditions of producing activated carbons have been studied to recycle as a higher value-added product. This study consists of two processes, the production process of charcoals from waste timbers by low temperature pyrolysis and the production process of activated carbons from the charcoals by chemical activation reaction. This paper deals with the production process of activated carbons from the charcoals by chemical activation reaction. As an alkali has been generally used as an activating agent, KOH and NaOH which react well with a carbon were used in this study. As a result of the experiments, it is confirmed that activated carbons made with KOH treatment had superior values in physicochemical properties to NaOH, showing that there was no remain of KOH at the surface of the charcoals while there was $3{\sim}4%$ of NaOH remaining after the experiments. Thus, it is concluded that KOH reacted more actively with a charcoal than NaOH. Moreover, it was also found that values in physicochemical properties when using a Pinus koraiensis are superior to the ones when using a Pinus rigida. The optimal mixing ratio of an activating agent to a charcoal was 400 wt.%. To improve the physicochemical properties, activated carbons were washed out by distilled water after neutralization with SM hydrochloric acid solution. When activated carbons were produced from a Pinus koraiensis in this optimal conditions, value of BET surface area was found to be approx. $2400\;m^2/g$.

• Journal of Soil and Groundwater Environment
• /
• v.12 no.4
• /
• pp.86-93
• /
• 2007

In recent tests using tracer have been frequently conducted by fluorescent tracers. In this study, granular activated charcoal (GAC) as a detector for the fluorescent tracers (rhodamine WT and uranine) was investigated through laboratory and field tests. In the laboratory tests, tracer concentrations of rhodamine WT and uranine determined by the GAC were slightly different from those of standard solutions but they were excellent in linearity. Results show that GAC is excellent as tracer detector when concentration of the fluorescent tracers is greater than 10 & micro; g/L whileas no obvious differences in mixed solutions of the two tracers due to interferences. Compared to conventional methods of water sampling, field results shows a high potential of GAC as a tracer in the field. Our results also show that wet analysis is better for the lower concentrations of tracers whileas dry analysis is good for high concentrations of tracers. This study demonstrates that fluorescent tracer detection using the GAC is very useful and economical for a hydraulic connection between target areas and very longer period of the tracer test.

• Horticultural Science & Technology
• /
• v.16 no.3
• /
• pp.347-349
• /
• 1998

Slow sand filtration was modified and applied for the determination of eliminating efficacy of various fungi and for recommending an easy approach to growers. After 1,500 liter filtration, Fusarium oxysporum was eliminated by several substrates such as activated charcoal (92.5% elimination), silica (90.8%), vermiculite (90.5%), sand (82.3%), perlite (50.4%), and hydroball (21.2%). Silica was able to eliminate several fungi by maximal ratio, which was corresponded to Fusarium oxysporum 120 cfu/mL. Collectotrichum lagenarium 98 cfu/mL. Phytophthora capsici 82 cfu/mL, Botrytis cinerea 62 cfu/mL, Pythium spp. 42 cfu/mL, and Sclerotinia ssp. 52 cfu/mL. In this case, the change of EC was minor and pH was maintained to about 7. In deep flow culture of 'Ddooksum Cheokchookmyeon' lettuce and 'Seokwang' tomato, silica-, activated charcoal-, and vermiculite-based filtration system successfully eliminated Fusarium oxysporum and Phytophthora capsici from the nutrient solution. As a result, these plants were not diseased by ten weeks after inoculation. With this system, growers can easily control the root-zone fungi in the recirculating hydroponic system.