• Journal of the Mineralogical Society of Korea
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• v.27 no.3
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• pp.115-124
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• 2014

In order to leach Au and Ag from gold-silver bearing sulfide concentrate, the sulfide concentrate was ground in a ball mill for a dry pre-treatment and a wet pre-treatment process. Mineralogical studies and thiourea leaching experiments were carried out with the pre-treated sulfide concentrate. The results of the pre-treatment with the concentrate samples showed the mean particle size and iso-electrical potential was smaller in the dry pre-treatment sample than in the concentrate sample, and the contents was lower in the wet pre-treatment sample than in the dry pre-treatment sample. In XRD analysis, amorphous properties were only shown in the wet pretreatment sample. The results of the concentrate sample leaching experiments showed that the best Au, Ag leaching parameters were when the addition of thiourea was at a 1.0 g concentration, ferric sulfate was 1.0 M, sulfuric acid was 2.0 M and the leaching temperature was at $60^{\circ}C$. The Au, Ag leaching rate was always much greater and faster with the wet pre-treatment samples than with the dry pre-treatment samples. Accordingly, it is expected that more Au, Ag can be leached in an eco-friendly methodology using wet pre-treatment. The pre-treatment could be improved with an optimized grinding additive reagent and through researching grinding time in future non-cyanide processes.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.133-137
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• 2011

In this study, illite was size-reduced using a wet-ball-milling treatment to improve its dispersion. Changes in illite particle size, size distribution, and dispersion characteristics after varying the treatment period were investigated. And the dispersion and dispersion stability of illite solution after 2 h wet ball milling treatment with different pH conditions were also evaluated. The illite particle size significantly decreased as the treatment time increased and the size reduction effect of wet ball milling deteriorated above 2 h treatment time. In addition, illite particle size was more evenly distributed as the treatment time increased. X-ray diffraction (XRD) analysis showed that no crystal structural changes of illite were induced, but the characteristic peak of illite the weaker due to the size reduction and exfoliation, as the treatment time increased. Zeta potential analysis showed that the illite dispersion improved, as the treatment time increased. The illite wet-ball-mill treated at pH 2 had the lowest dispersion stability. Illite dispersion and dispersion stability increased as pH increased, due to the increase in surface ionization. Hence, the results showed that as the treatment time increased, the illite particle size decreased, and dispersion and dispersion stability improved due to the increase in surface energy and repulsion force between particles.

• Journal of Korean Society on Water Environment
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• v.29 no.4
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• pp.568-573
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• 2013

In this study, we conducted whole effluent toxicity (WET) proficiency testing based on the results which $EC_{50}$ value of 3 types (A, B, C) unknown samples calculated from 32 water quality measurement agencies in Korea. WET proficiency testing was expected to their improve of analysis skill and ensure reliability of analysis results. Ultimately, it is intended to promote the reliable enforcement of WET. WET proficiency testing was evaluated using the z-score, robust z-score and the results showed that 30 participating agencies were "compliance". In addition, $EC_{50}$ values of "unknown sample A" were the normal distribution. Therefore, "unknown sample A" was considered as the most suitable standard toxicity substance.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.3
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• pp.33-40
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• 2005

In this study, a nano-colloidal silica sol was applied to control the anti-slip property by spraying on kraft paper. Two kinds of nano-colloidal silica sol which have cationic and anionic charge were applied in kraft paper, and the friction and physical strength properties of kraft paper were investigated. The application of colloidal silica sol on wet web in wet-end process by spraying method was tried to improve the friction property and to avoid the general problems of machine contaminations caused by the scattering of sprayed silica particles in dryer part. The physical properties of sheet were also improved by the application of wet web spraying method, and the optimum conditions of wet web spraying operation were closely related with the conditions of pH and electrical charge of wet web and silica sol.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.4
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• pp.21-32
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• 2018

Objectives This study was designed to investigate the effects of wet cupping on Wisu (BL12) in non-acute low back pain patients. Methods We recruited 30 participants for this study. Fifteen patients were randomly assigned to the Wisu (BL21) treatment group (WT group) and 15 were assigned to the non-acupoint treatment group (NT group). Both groups were treated with the pricking-cupping bloodletting method three times. Values at baseline and follow-up were analyzed by Wilcoxon signed rank test and the differences between the two groups were determined by Wilcoxon rank sum test. p-values less than 0.05 were considered significant. The primary outcome was the visual analogue scale (VAS), and secondary outcomes were the Oswestry disability index (ODI), Rolland-Morris disability questionnaire (RMDQ), Euroqol-5 dimension questionnaire (EQ-5D) and finger-to-ground distance (FTGD). These outcomes were measured on the day of first treatment before the procedure and on follow-up 7 days after the last treatment. Results Significant changes were identified in the VAS for pain and ODI in each group after wet cupping treatment on Wisu (p<0.05). However, no significant changes were found between groups. Meanwhile, RMDQ and EQ-5D were significantly decreased only in the NT group (p<0.05) without any differences between groups. FTGD was decreased in both groups, but not significantly. Conclusions Wet cupping with both Wisu treatment and non-acupoint had significant effects on non-acute low back pain, although there were no differences between the two groups. A large-scale study is needed to identify the effect of wet cupping on Wisu.

• The Journal of Korean Medicine
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• v.22 no.3
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• pp.119-128
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• 2001

Objectives: Daechu (Dazhui: GV 14 (Governor Vessel))-point is located between the spinous process of the 7th cervical vertebra and that of the 1st thoracic vertebra. GV 14 has been used to treat high fever, neck pain, common cold, headache and so on. Fever may badly affect the improvement of stroke patients, so we investigated whether wet-cupping at GV 14 had effects on fever. Methods: In this study, 100 stroke patients were studied from Nov. 1999 to Oct. 2000. They were divided into the Sample group (n=49) and Control group (n=5l). The Sample group (n=49) was divided into Sample-Severe (n=2l), Sample-Mild (n=12), and Sample-Normal groups (n=16) and the Control group (n=5l) was divided into Control-Severe (n=8) and Control-Mild (n=43). We checked body temperature 6 times (just before treatment, after 30 ruin., 60, 90, 120 (2 hrs.), and 240 ruin. (4 hrs.)) in the Sample group and 3 times (just before treatment, after 120 min. (2 hrs.), and 240 ruin. (4 hrs.)) in the Control group. Results: In comparison with fever between before treatment and after 2 and 4 hours in each group, fever in the Sample subgroups decreased significantly in all cases, fever in the Control subgroups didn't decrease significantly in most cases except fever after 4 hours in the Control-Mild group. In comparison with fever differences between the Sample and Control group, fever of the Sample group more significantly decreased than that of the Control group in all comparisons. In comparison with fever among sample subgroups, fever of the Sample-Severe group decreased more than that of the Sample-Mild group but it was not significant. Conclusions: This study suggested that wet-cupping at GV 14 has significant effects on fever in stroke patients. We hope that this treatment will be used more widely as an emergent treatment.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.3 s.31
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• pp.242-251
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• 1989

The purpose of this study was to investigate the changes in easy-care and strength properties of the wet fixation processed viscose rayon fabrics. Rayon fabrics were treated with mixed resins of melamine formaldehyde (MF) and DMDHEU by one bath and two bath wet fixation processes. The MF/DMDHEU mixed resin concentrations were 50/100, 50/150, 100/100, 100/150 and 150/100(g/1). Magnasium chloride was used as a catalyst. Treated fabrics were evaluated by nitrogen content, DP rating, wrinkle recovery angle, breaking strength, tearing strength and abrasion resistance. The properties were compared to the fabrics treated by conventional Pad-Dry-Cure (PDC) method. Wet fixation processed fabrics showed DP ratings of higher than 3 and higher than 275 degrees of wrinkle recovery angles in all the mixed resin concentrations. Wet fixation processed fabrics showed increase in breaking strength and tearing strength but decrease in abrasion resistance. However, the decrease in abrasion resistance was much less than the conventional PDC treated fabrics. The one bath wet fixation processed fabrics showed better physical properties than the two bath processed fabrics in general. The optimum treatment condition was the mixed resin concentration of MF/DMDHEU, 100/100 g/l in one bath wet fixation process.

• Journal of Powder Materials
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• v.17 no.2
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• pp.113-122
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• 2010

Two kinds of oxide-dispersion-strengthened (ODS) 316L stainless steel were manufactured using a wet mixing process(wet) and a mechanical alloying method (MA). An MA 316L ODS was prepared by a mixing of metal powder and a mechanical alloying process. A wet 316L ODS was manufactured by a wet mixing with 316L stainless steel powder. A solution of yttrium nitrate was dried after being in the wet 316L ODS alloy. The results showed that carbon and oxygen were effectively reduced during the degassing process before the hydroisostatic process (HIP) in both alloys. It appeared that the effect of HIP treatment on increase in impact energy was pronounced in the MA 316L ODS alloy. The MA 316L ODS alloy showed a higher yield strength and a smaller elongation, when compared to the wet 316L ODS alloy. This seemed to be attributed to the enhancement of bonding between oxide and matrix particles from HIP and to the presence of a finer oxide of about 20 nm from the MA process in the MA 316L ODS alloy.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.70-76
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• 2017

Objectives: This on-site study was performed to evaluate the reduction efficiency of an air cleaner on particulate matters and biological agents in a swine facility. Materials and Methods: Particulate matter was measured using a real-time monitoring recorder and biological agents were sampled with a one-stage impactor and then analyzed based on the microbial culture method. An experimental process for the reduction effect on airborne pollutants through air cleaner operation consisted of three conditions: no treatment, wet scrapper by water spray and wet scrapper by disinfectant spray. Results: Geometric mean levels of particulate matter(TSP, $PM_{10}$, $PM_{2.5}$ and $PM_1$) were presented at $1,608{\mu}g/m^3$, $1,373.8{\mu}g/m^3$, $401.8{\mu}g/m^3$ and $144.5{\mu}g/m^3$ for no treatment; $1,503{\mu}g/m^3$, $1,017{\mu}g/m^3$, $159.4{\mu}g/m^3$ and $69.8{\mu}g/m^3$ for wet scrapper by water spray; and $1,222.17{\mu}g/m^3$, $477.17{\mu}g/m^3$, $33.2{\mu}g/m^3$ and $11.1{\mu}g/m^3$ for wet scrapper by disinfectant spray, respectively. In the case of biological agents, the geometric averaged concentrations of total airborne bacteria and fungi were as follows: $45,371cfu/m^3$ and $13,474cfu/m^3$ for no treatment, $43,286cfu/m^3$ and $8,610cfu/m^3$ for wet scrapper by water spray, and $2,440cfu/m^3$ and 1,867 cfu/ for wet scrapper by disinfectant spray, respectively. Regardless of particulate matter and biological agent, the highest concentrations were found for no treatment, while the lowest concentrations were found with wet scrapper by disinfectant spray. Conclusions: Based on the results obtained from this on-site evaluation, there was a significant reduction effect on particulate matter and biological agents through the application of an air cleaner in this study.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.2
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• pp.97-103
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• 2003