• Journal of the Korean Ceramic Society
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• v.36 no.1
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• pp.89-96
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• 1999

Manufacturing conditions of the porous alumina mold were established to overcome various limits of the gypsum mold. For the preparations of the porous alumina mold, an activated charcoal was added to the Al2O3 with the wt% variation and then mixed. The binary slurry was study dispersed based on the examination of the ESA and rheological behaviro. The cylinder type alumina mold was cast in the gyspum mold and characterized by the shrinkage rate at the variable sintering temperature and the resistance against wear. It was proper to make a sintering of the Al2O3 by the surface diffusion which was non-shrinkage sintering mechansim, and intergranular neck growed stronger while sintering was being made. We studied a sintering by three categories; 1) thermodynamic method below 1,000$^{\circ}C$, 2) kinetic method above 1,000$^{\circ}C$ and 3) combined method. In the results of the respective works, combined method was superiro to the others. The prepared Al2O3 mold had relatively high strength, low drying rate, the resistance against the acid or base and good casting behavior.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.5
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• pp.107-113
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• 2000

The purpose of this study is to investigate the effects of soil amendments for reducing soil compaction at heavy traffic area in golf course. Major results of this research are summarized at follows: 1. In the Lab. experiment, the porosity was improved significantly when the materials, such as peatmoss, charcoal, and tire chip mixtures were used respectively. Especially mixture of sand and 20% peatmoss showed higher effectiveness (10%) in porosity, comparing with ordinary sand. This soil mixture(sand 80%+peatmoss 20%) was observed the best in water retention, soil hardness and hydrauric conductivity. 2. In the greenhouse experiment, traffic pressure was given 7 times a day on several combination of mixture treatments to see the top dry weight. The soil mixture of 20% peatmoss showed the highest in the top dry weight. When the more traffic pressure(15 time/day) were given on the different treatment, the top dry weight was significantly reduced. However, the mixture of 20% peatmoss also had the least influence on this type of heavy traffic. 3. In the field experiment, the soil amendments were treated in traffic area f golf course, and observed at 30days, 60days, 90days, 120days after treatment. Visual turf quality(color), root length and soil compaction were compared to those of control. As a result, overall treatments with soil amendments were effective, which showed better turf quality and less soil compaction. 4. In the field test, physical characters of soil (such as soil hardness and hydrauric conductivity) in sand+tire chip+peatmoss(60:20:20, %, v/v) treatment was significantly improved. Also in the slow increasing of traffic, the soil compaction was the most effective in reducing soil hardness.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.500-509
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• 2009

Passive samplers have been used for many years for the sampling of organic vapors in work environment atmospheres. Currently, all passive samplers used in domestic occupational monitoring are foreign products. This study was performed to evaluate variable parameters for the development of passive organic samplers, which include the geometry of the device and diffusive length for the sampler design. Four prototype diffusive lengths; A-1(4.5 mm), A-2(7.0 mm), A-3(9.5 mm), A-4(12.0 mm) were tested for adsorption performances to a chemical mixture (benzene, toluene, trichloroethylene, and n-hexane) according to the US-OSHA's evaluation protocol. A dynamic vapor exposure chamber developed and verified by related research was used for this study. The results of study are as follows. The results in terms of sampling rate and recommended sampling time test indicate that the most suitable model was A-3 (9.5 mm diffusive lengths on both sides) for passive sampler design in time weighted average (TWA) assessment. Sampling rates of this A-3 model were 45.8, 41.5, 41.4, and 40.3 ml/min for benzene, toluene, trichloroethylene, and n-hexane, respectively. The A-3 models were tested on reverse diffusion and conditions of low humidity air (35% RH) and low concentrations (0.2 times of TLV). These conditions had no affect on the diffusion capacity of samplers. In conclusion, the most suitable design parameters of passive sampler are: 1) Geometry and structure - 25 mm diameter and 490 $mm^2$ cross sectional area of diffusion face with cylindrical form of two-sided opposite diffusion direction; 2) Diffusive length - 9.5 mm in both faces; 3) Amount of adsorbent - 300 mg of coconut shell charcoal; 4) Wind screen - using nylon net filters (11 ${\mu}m$ pore size).

• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.340-345
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• 2016

The kiwi fruit (Actinidia deliciosa cv. 'Hayward') should be ripened at any step during postharvest handling before consumer consumption. This is essential for freshly harvested kiwi fruit. But, this requires correct temperatures and ethylene concentrations. More testing of a newly developed ethylene generator using charcoal for commercial purposes is needed. This study was conducted to investigate the optimum storage temperatures and the effect of ethylene on the postharvest quality of kiwi fruit. Three different ethylene concentrations of 10, 50, and $100{\mu}L{\cdot}L^{-1}$ were used on fresh kiwi fruit stored at different temperatures of 10, 15, and $20^{\circ}C$. The quality changes of the fruits were assessed by sensory evaluation and by measuring firmness, soluble solids content, titratable acidity, and ethylene production. Higher storage temperatures and ethylene concentrations softened the kiwi fruit quickly and led to the rapid loss of acidity while soluble solid contents of fruit increased to a significant extent during the same storage period. Similarly, the firmness of ethylene-treated fruits stored at 20 and $15^{\circ}C$ dramatically decreased in the experiment while treated fruits stored at $10^{\circ}C$ decreased only slightly. Quality characteristics of kiwi fruits stored at 15 and $20^{\circ}C$ were better than those of fruits at $10^{\circ}C$. With regards to the effect of temperature, fruits stored at lower temperatures took a longer time to ripen and retained their quality longer. The newly developed ethylene generator maintained the ethylene concentration in the 5 kg box at $40-400{\mu}L{\cdot}L^{-1}$. The ethylene generator could also be used to soften persimmons.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.137-141
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• 1984

Crude sap, which was extracted from six Amaranthaceae plants, inhibited local lesion formation on Nicotiana glutinosa by tobacco mosaic virus(TMV) infection. Especially the remark. able inhibitory effect to TMV infection was shown on leaves of N. glutinosa precoated with the sap from Amaranthus mangostanus. The inhibitory activity of the sap from A. mangostanus was stable to storage in vitro for I day and to dilution 1/4 of the sap with distilled water. However, its activity was lost when the sap was heated at $70^{\circ}C\;to\;100^{\circ}C$ for 10 minutes. When the leaves of N. glutinosa precoated with the sap were sprayed with water, the inhibitory effect to TMV infection was maintained for 2 days. The A. mangostanus sap readjusted pH 3, pH 5, or pH 9 with 1 N HCl or 1 N NaOH did not decline the inhibitory action but the sap absorbed with $5\%\;to\;15\%$ charcoal completely lost their action. The protein components purified from A. mangostanus sap revealed three major bands by $5\%\;to\;15\%$ polyacrylamide gel electrophoresis and the top component of which showed the inhibitory action to TMV infection.

• Clinical and Experimental Reproductive Medicine
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• v.13 no.2
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• pp.187-193
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• 1986

The purpose of this study was to establish optimal conditions for progesterone receptor assay using rat uterus, therby applying this system to understand action mechanism of progesterone in female reproductive organ and to evaluate physiological and pathological conditions in female reproduction. The results obtained were as follows 1. $^3H-R5020$ seemed to be more stable than 3H-progesterone as a ligand. 2. Optimal incubation time for ligand and receptor binding was 4-5 hrs at $4^{\circ}C$. 3. For the separation of bond and free ligand, optimal charcoal incubation time was 20 mins. 4. 2-3 mg cytosolic protein/ml was optimal for the binding of ligand. 5. Endogenous progesterone did not influence binding of ligand and receptor unless endogenous progesterone levels were extremely high as in case of pregnancy. 6. Dissociation rate for progesterone receptor was 1.22 nM. 7. $^3H-R5020$ did not bind to corticoid binding globulin (CBG), suggesting that addition of cortisol is saturate CBG was, not necessary as far as $^3H-R5020$ was used as a radioligand. It is, therefore, considered that this assay system established with these conditions might be used for the research as well as clinical routine purposes.

• Journal of Acupuncture Research
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• v.25 no.4
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• pp.59-69
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• 2008

Objectives : The purpose of this study was to observe the effects of acupuncture and electro-acupuncture(EA) at $LI_{11}$ on intestinal motility in rats. Methods : We made over-activated and suppressed state of intestinal motility with carbachol and loperamide in rat and carried out acupuncture with needle retained(NR), low frequency(2 Hz) EA and high frequency(100Hz) EA at $LI_{11}$ before or after the administration of carbachol or loperamide. The charcoal travel rate was measured to evaluate the intestinal motility. Results : 1. NR, 2Hz EA and 100Hz EA at $LI_{11}$ showed no significant influences on intestinal motility of rat in normal state. 2. All of the pre-treatment and post-treatment of NR, 2Hz EA and 100Hz EA at $LI_{11}$ showed no significant effects than control group on intestinal motility of rat which was over-activated with carbachol. 3. The pre-treatment of 2Hz EA and 100Hz EA at $LI_{11}$ on intestinal motility of rat which was suppressed with loperamide showed no significant influences but in the L-$LI_{11}$-EA(L) and L-$LI_{11}$-EA(H) groups, intestinal motility was significantly increased than L-control group. Conclusions : These results suggest that acupuncture and EA on $LI_{11}$ have preventive effect and therapeutic effect on suppressed intestinal motility, and EA is more effective than NR.

• Journal of Acupuncture Research
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• v.25 no.4
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• pp.11-29
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• 2008

Objectives : The purpose of this study was to observe the effects of acupuncture and electro-acupuncture at $LI_4$ on intestinal motility in rat. Methods : We made over-activated state of intestinal motility with carbachol and suppressed state of intestinal motility with loperamide in rat and carried out needle retention acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture at $LI_4$ or sham point in rat devided into pre-treatment group and post-treatment group. and we resulted as follow for measuring charcoal travel rate to observe intestinal motility. Results : 1. Any of needle retention acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture at $LI_4$ have no significant influences on intestinal motility of rat in normal state. 2. All of the pre-treatment and post-treatment of needle retention acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture didn't significantly decrease intestinal motility in rat which over-activated with carbachol. 3. Pre-treatment of needle retention acupuncture and high frequency electro-acupuncture significantly increased intestinal motility in rat which suppressed with loperamide. 4. Post-treatment of needle retention acupuncture, low frequency electro-acupuncture and high frequency electro-acupuncture significantly increased intestinal motility in rat which suppressed with loperamide. Conclusions : These results suggest that acupuncture on $LI_4$ have preventive effect and therapeutic effect on suppressed intestinal motility, and especially high frequency electro-acupuncture is more effective.

• Journal of The Korean Society of Clinical Toxicology
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• v.7 no.1
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• pp.19-22
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• 2009

Although Nerium indicum poisoning is a globally rare occurrence, Nerium oleander poisoning is known to occur frequently in the Mediterranean regions. To our knowledge, this is the first reported case of accidental Nerium indicum poisoning in Korea. Its poisoning symptoms and signs are similar to that of digitalis poisoning, because of the presence of cardiac glycosides in Nerium indicum. A 16-year-old boy was admitted to the emergency department four hours prior to the accidental ingestion of Nerium indicum petals. The patient complained of nausea, vomiting, and dizziness. His initial vital signs were stable; laboratory blood test results were within normal levels, except for the blood digoxin level (1.5 ng/dL). An electrocardiogram (ECG) analysis showed normal sinus rhythm, progressive PR prolongation and second-degree Morbiz type I AV block. Conservative treatments including activated charcoal administration were conducted, because toxic symptoms and signs were not severe. The patient was admitted to the intensive care unit for close observation. His ECG was converted to normal rhythm after 1 day and the toxic symptoms and signs were completely resolved after 4 days.

• Journal of Fashion Business
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• v.11 no.3
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• pp.79-86
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• 2007

The purpose of this study is to understand the dyeing properties and color analysis of fabrics knitted with ramie, cotton, wool and acrylic by using scoria and to analyze whether the knitted fabrics can be used for industrialization by measuring color fastness after and before sliver-nano process. The following is the conclusions. Firstly, when ramie fabric regarding cotton, wool and acrylic was dyed at the temperature of $50^{\circ}C$ for fifteen minutes by using 10, 25, 50, 100g/ $\ell$ of scoria, dyeing absorption gradually increased up to 50g/ $\ell$, and over the point of 50g/ $\ell$ it showed slow increase. Secondly, regarding saturation, among ramie fabric, wool, cotton and acrylic, wool appears as the lowest brightness. Therefore, it can be dyed with bright color and the highest value. In terms of the value of chromaticity, wool also emerges as the lowest brightness. On the contrary, acrylic showed the lightest red as it had the value of the smallest b. Cotton takes the lightest yellow as the b value of the cotton showed the smallest. Thus, scoria dyestuff is a material that showed strong red and yellow on knitted fabric mixed with wool that is the biggest a. b value. Thirdly, in terms of dyeing fastness, sunlight fastness did not show noticeable differences before and after silver-nano processes, but in terms of washing and friction fastness, the material processed by silver-nano indicated that all knitted fabrics are over 4-5 point. which means silver-nano process can be effective for the industrial applications. As mentioned above, as a result of dyeing knitted fabrics with scoria, this study found a possibility of dyeing in the fabric materials, and if there is deeper dyeing experiments, fastness experiments and speculations, it might be possible to be a big issue just like loess and charcoal.