• Biomedical Science Letters
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• v.8 no.2
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• pp.101-106
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• 2002

The purpose of this study was to test the capacity of automatic tablet crusher. The Automatic tablet crusher not only saved crushing time, but also removed floating fine powders that was occurred during crushing and caused allergy. The characteristics of powder produced by this crusher were as follows: First, to meet the condition as powder after pulverizing 5∼10 g tablet it took 6 to 12 seconds crushing time. But six seconds would do to get powder f3r oral administration. Second, when the quantity of medicine was measured by HPLC, powder from automatic crusher showed higher than that from pestle. HPLC chromatogram indicated that there was no change of medicine in the process of pulverization.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.8
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• pp.76-85
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• 2003

In this paper, a technical method for removing the solder from PCBs has been proposed to simplify the pulverizing process and to get higher quality of materials for recycling of the electronic parts in the Printed Circuit Boards (PCBs). There are several techniques to remove the solder from PCB, such as physical and chemical method, vibration, suction and blowing and so on. Among them, the suction technique turned out the best method by investigation. In the suction method, there are three variables for removing the solder. They are a temperature of the thermal wire, a velocity of moving PCB and a gap between PCB and thermal wire. To find the optimal variables for the system, an experiment has been conducted by a trial and error method. The optimal variables were found $220^{\circ}C$ of temperature, 11.58mm/s of velocity, 10mm of gap (A gap between suction hole and bottom of PCBs is 5mm). The result of the experiment shows that 50% of the solder were removed.

• Journal of Ginseng Research
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• v.33 no.4
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• pp.305-310
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• 2009

Phenanthrene, one of the polycyclic aromatic hydrocarbons, has been known to be toxic to the environment. In this investigation, the protective effect of red ginseng on phenanthrene-induced oxidative DNA damage was evaluated using Comet assay in A549 cells. Red ginseng's cytoprotective effect on phenanthrene-induced hemolysis was also investigated. This study's findings show that oxidative DNA damage and hemolysis were significantly prevented by red ginseng treatment. Notably, it was found that pulverizing red ginseng into ultra-fine particles even enhanced its protective effects against DNA damage and hemolysis. The results suggest that particle size reduction seems to effectively enhance red ginseng's pharmacological efficacies.

• Journal of the Korea Institute of Building Construction
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• v.6 no.4 s.22
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• pp.93-98
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• 2006

Admixture materials are used in mixing concrete or mortar to improve quality and performance of the concrete. This study examines the potential use of talc as a substitute for cement, the benefits of recycling waste resources for economical efficiency and quality improvement of concrete. The test was carried out by replacing the plain mix with fine grains of talc at the rate of 10%, 20%, and 30%. Talc was divided into three groups depending on the degree of pulverizing. For wet concrete, porosity, slump, bleeding per unit, and setting time by penetration resistance were measured; similarly, for dry concrete, strength and watertight Property were tested. Test results showed that the amount of bleeding and setting time could be shortened, but the strength and watertight proofing severely deteriorated. However, at the replacement rate of 10%, talc showed equal performance with the plain at all degrees of pulverization, which suggests its potential use as admixture material.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.109-110
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• 2021

An attempt has been made on a constructive approach to evaluate the performance of snail shell ash (SSA) for its corrosion performance under marine environments. Corrosion performance of steel rebar in chloride contaminated SSA with (0% to 50%) replacement levels of cement extract medium was examined through electrochemical and weight loss techniques. Initially, snail shell powder (SSP) is made by pulverizing and subsequently SSA is by thermal decomposition methods. A critical level of 20 % SSA improved both corrosion resistance properties of cement extracts. SSA is a suitable replacement material for natural limestone in cement productions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.353-358
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• 2012

This study was carried out to evaluate antioxidant and anticancer activity of crudes extracts from colored corn (Zea mays. L.) among particle size with different pulverizing methods (pin mill and ultra fine pulverizer). In cytotoxicity test using extracts from the flours grounded by pin mill and ultra fine pulverizer respectively, it showed that A-549 was the highest anticancer activity among in vitro using 4 cancer cell line types (Hep-G2, A-549, HCT-116 and MCF-7). Assessing the antioxidant activities of crude extracted from different pulverizing methods was measured by trolox equivalent antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP). Higher scanvening activity against free radical was observed in the crude extracted from small particle size flours of colored corn than in those of the big particle size.

• Journal of Life Science
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• v.9 no.2
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• pp.194-200
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• 1999

Grinding aid is a necessary unit operation when the raw materials are handled in solid form, and the purpose is to improve the bioavailability by reducing the particle size. For the particle design of pefloxacin, the dry planetary ball-mill was used. With the drying process, 330 g of zirconia ball with its size of 2 mm in diameter and 10 g of pefloxacin were transferred to the pot and mixed well. The mixture was ground at 112 rpm (60 Hz) for 15, 30, and 60 min, respectively. The most satisfactory grinding products were generated at 15 min of grinding time for their particle size. The volume mean diameter $\X_50$ of the grinding products was 2.97 $\mu$m. X-ray diffraction (XRD), differential scanning calorimeter (DSC), and infrared spectroscopy (IR) patterns were relatively unchanged before pulverizing pefloxacin and in the progress of grinding. Thus, these results suggest that this pulverizing method can be used for grinding products without evident effect on stability of the drug pefloxacin. Dissolution test was carried out to set up the optimal detective condition against residual antibacteria of fish by HPLC. The grinding pefloxacin for 15 min is most effective in dissolution test.

• Magazine of the Korea Concrete Institute
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• v.6 no.5
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• pp.131-139
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• 1994

The min aim of thls study was to evaluate the effect of particle slze of the fly ash as a cement additive. Experimental work was carried out with three different sizes of fly ash. 18.58, 8.95 and 4.02{$mu}m$ in average radius. Namely, the effect of particle size variation of fly ash on the physical properties of cement paste was investigated. The jluidity was decreased with increasing the addition of fly ash to cement paste regardless of the particle size variation. The decrement of the fluidity of the pulverized fly ash was higher than that of the spherical fly ash. On the other hand, the pozzolan reactivity increased with lowering particle size. In the case of specimens with 5% up to 10% addition of fly ash having a particle size of 4.02{$mu}m$. the compressive strength was increased as compared with the plain specimens before curing for 28 days and showed higher value above 800kg /$cm^2$ when cured for 60 days.This increased compressive strength was ascribed to both the closer packlng of fine particles and the pozzolan reactivity of fly ash. These results were comfirmed by measuring both the porosity of the specimens and Ca(OH ), contents remained in specimens. This work showed that could be effectively ut~lized as a blending material without any de crease in the strength of early hydration stage if we can control the particle size of fly ashes by sizing or pulverizing.

• Journal of Ginseng Research
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• v.26 no.2
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• pp.79-84
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• 2002

In this study, cell cracker method as a non-collision method was evaluated for the possibility in manufacturing red ginseng powder. In color value of red ginseng powder, the L values indicating brightness were 68.18 for hammer mill (group A) and 72.08 for cell cracker (group B). The a values (redness) and b values (yellowness) were 4.21 26.56 for group A and 5.73, 28.36 for group B, respectively. As an extraction time increased, the absorbances at 420 nm of water extract of both groups were increased. In the loose bulk density, tapped bulk density and volume reduction radio indication the of powder in group A were less than those in group B. In both groups, the angles of side of red ginseng powder were shown less value than the angles of side of the powder. These two angles in group A were lets than those in group B. In sensory evaluation, the touchness between both groups was, not observed significant difference. In the contrary, the color and flavor, main factors affecting the overall quality of red ginseng powder product of group B were shown superior to those of group A. The overall preference of group B was shown higher than that of group A.

• Resources Recycling
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• v.30 no.4
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• pp.35-45
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• 2021

The humidity-control function and manufacturing characteristics of wood-wool boards using waste-paper-mulberry fiber were analyzed in this study. For the manufacture of wood-wool boards, the pulverizing times of waste-paper-mulberry fibers were controlled at 30, 60, 120, and 180 s, and the mixing amounts were controlled by adding 0%, 3%, 6%, and 9%, respectively, as compared to cement. Analysis of the moisture adsorption and desorption characteristics of the wood-wool boards controlled for pulverizing time revealed that the wood-wool board with 60 s of pulverized fiber exhibited the best adsorption and desorption performances. It was estimated that the adsorption and desorption performances of the material itself were adequate even when the boards were mixed because of minimal damage to the fiber. In addition, an analysis of the absorption and desorption characteristics of the fiber-mixture-controlled wood-wool boards showed that the 6%-mixed wood-wool board had the best absorption and desorption performances of 291.00 g/m² and 108.75 g/m², respectively.