• The KSFM Journal of Fluid Machinery
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• v.19 no.3
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• pp.10-13
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• 2016

The wet-air oxidation in gravity pressure reactor is effective for organic waste treatment with energy saving under high pressure and high temperature. But its oxidation control is difficulty because its multi-phase flow characteristics is very complicated. The flow characteristics of an oxidizer feed section in the gravity pressure reactor were investigated using numerical method which are verified by comparison with experimental results. In this study, the results showed that the flow rate of oxidizer have an effect on the generation of bubble around feed section.

• Journal of the Korean Ceramic Society
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• v.30 no.3
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• pp.215-221
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• 1993

The Hydroxyapatite powders were prepared by Wet-direct and Hydrothermal synthesis using Ca(NO3)2.4H2O and (NH4)2.HPO4.Stoichiometric and good cristalline HAp powders were obtained 9$0^{\circ}C$ by wet-direct process. The aspect ratio of HAp powders prepared by hydrothermal synthesis was increased with increasing synthetic temperature. The HAp particles obtained at 20$0^{\circ}C$ for 10hr were needle shaped ultra fine crystals, about 100nm in size. Small amount of TCP was obtained above 80$0^{\circ}C$ after heat-treatment of hydrothermally synthesized HAp but good crystalline HAp phase was maintained up to 120$0^{\circ}C$ as the primary phase.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.12
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• pp.1106-1110
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• 2005

We fabricated (110) silicon hard master by using anisotropic wet etching for embossing. The etching chemical for the silicon wafer was a TMAH $25\%$ solution. The anisotropic wet etching produces a smooth sidewall surface and the surface roughness of the fabricated master is about 3 nm. After spin coating an organic-inorganic sol-gel hybrid material on a silicon substrate, we employed hot embossing technique operated at a low pressure and temperature to form patterns on the silicon substrate by using the fabricated master. We successfully fabricated the multi-mode planar optical waveguides showing low propagation loss of 0.4 dB/cm. The surface roughness of embossed patterns was uniform for more than 10 times of the embossing processes with a single hydrophobic surface treatment of the silicon hard master.

• The Journal of Pediatrics of Korean Medicine
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• v.24 no.1
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• pp.46-56
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• 2010

Objectives The purpose of this study is to report a Atopic dematitis patient treated by Horminis Placenta external wet therapy. Methods The patient was treated by acupuncture, herb medicine, especially Horminis Placenta external therapy. Kunz type, SCORAD index and Vas scale were used to measure the progression. Results and Conclusions We had evaluated the score during admission. SCORAD index include the extent, the intensity, pruritus, sleeping loss had increased from 52.88 score to 21.26 score. And the symptoms had improved with treatment.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.80-84
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• 2014

The process of petroleum involves in a large amount of oily wastewater that contains high levels of chemical oxygen demand (COD) and toxic compounds. So they must be treated before their discharge into the receptor medium. In this paper, wet peroxide oxidation (WPO) was adopted to treat the oily wastewater. Central composite design, an experimental design for response surface methodology (RSM), was used to create a set of 31 experimental runs needed for optimizing of the operating conditions. Quadratic regression models with estimated coefficients were developed to describe the COD removals. The experimental results show that WPO could effectively reduce COD by 96.8% at the optimum conditions of temperature $290^{\circ}C$, $H_2O_2$ excess (HE) 0.8, the initial concentration of oily wastewater 3855 mg/L and reaction time 9 min. RSM could be effectively adopted to optimize the operating multifactors in complex WPO process.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2001.11a
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• pp.183-199
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• 2001

Alternative way of shaping fibers suitable for papermaking was introduced. Impact refining, which was done simply by hitting wet fibers with a metal weight vertically, was intended to keep the fibers from shortening and to cause mostly internal fibrillation. Virgin chemical pulp, its recycled one and OCC were used in the experiment. It was noticed from the experiment that impact refining on virgin chemical pulp kept the fiber length and Increased bonding properties greatly, However, in the recycled fibers from the chemical pulp, fiber length and bonding properties were decreased. In OCC, which seems to contain fractions of semi-chemical pulp and mechanical pulp (GP), and which is recycled pulp from corrugated boxes, fiber length and bonding properties were decreased disastrously. We believe recycled cellulosic fibers (recycled chemical pulp and OCC in this case), which went through hornification, were less resistant to the mechanical impact than virgin chemical pulp. For virgin chemical pulp, impact refining allowed no significant fiber length shortening, high WRV, and high mechanical strength.

• Journal of the Korean Ceramic Society
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• v.33 no.12
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• pp.1394-1402
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• 1996

The Silica gel with the density of 0.2g/cm3 and porosity of 90% was synthesized. The silica wet gel was dried and heat-treated under the ambient pressure after modification of the wet gel surface by TMCS. Specific surface area total pore volume and mean pore radius of dried gel were all increased with increasing heat treatment temperature and confirmed about 1400m2/g, 4.5cc/g and 8 nm respectively after heat treatment above 25$0^{\circ}C$. But the pore size distribution of dried gel was in the range of 1-100nm and was almost indepen-dent of temperature. As the result of external shape pore characteristics and microstructure of gel using SEM similar properties were observed between the silica gel synthesized in this study and the silica aerogel through the super critical drying.

• Textile Coloration and Finishing
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• v.11 no.3
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• pp.23-31
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• 1999

In order to investigate the detergency of the mixture of compact detergent and bleaching agent to fabric stained with a coffee and a red wine, respectively, and a japanese wet stained fabrics, to evaluation of detergency was studied under various washing conditions. In order to study the effect of alkaline agent addition on the detergency, the soda ash was added in the compact detergent system. The results are as follows : In a low temperature washing condition, the alkalinity of washing liquor effected more the removal of the composite stained fabrics than that of oilic stained fabrics. For the colored stained fabric such as red wine stained sample, the influence of the repeated washing treatment on the detergency was not significant factor. On the other hand, the influence of the repeated washing treatment for the coffee stained and japanese wet stained fabric on the detergency was gradually increased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.225-229
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• 1999

Unstable seedling stand establishment of wet direct seeding culture of rice is one of the major elements preventing the extension of its culture area. In order to develop methods of seedling stand improvement in direct seeded rice on flooded surfaces, three field experiments were conducted on silty loam soil using a cultivar 'Donjinbyeo' for three years, mainly focusing on water management after seeding and seed soaking with plant growth regulators (PGRs). Under the condition of shallow flooding after seeding, seedling stand rate increased and floating seedling rate decreased in both early and normal season seeding compared to deep flooding. With earlier draining time after seeding, there was a tendency towards preferential growth of the seminal root, increase of seedling stand and decrease of the floating seedling rate. Therefore the highest seedling numbers per unit area and the lowest floating seedling numbers were found upon drainage at 1 day after seeding (DAS), while a contrary tendency was shown upon conventional drainage at 7 DAS. Seed soaking with PGRs such as Metalaxyl or mixing of Metalaxyl with gibberellic acid (GA$_3$) significantly increased the seedling stand. In addition the effects of PGR treatment on seedling stand and the early growth of plants were greater under flooded conditions than under drained conditions after seeding, although draining of water after seeding improved the seedling establishment rate more when compared with the PGR treatment. These results suggest that draining management after seeding or maintaining of shallow flooding for a week is the most effective method to improve the seedling stand rate in wet direct seeding.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.09a
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• pp.22-22
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• 2019

Green stem disorder (GSD) of soybean (Glycine max (L.) Merr.) is characterized by delayed senescence of stems with normal pod ripening and seed maturation (Hobbs, 2006). GSD complicates harvesting of soybeans by significantly increasing the difficulty in cutting the affected plants. There is also the potential for moisture in the stems to be scattered on the seed, reducing the grade and storability of the seed. Not only the cause of GSD is yet unknown, but also GSD cannot be evaluated until maturity, therefore the method to evaluate GSD in early growth stage with high sensitivity is necessary. In previous studies, it has been reported that vegetative storage protein (VSP) accumulates and the syndrome of GSD appears in soybean after depod treatment (Fischer, 1999). Soybean VSP is a storage protein which is abundant in young sink leaves and degraded during seed fill (Wittenbach, 1982). Hence, we have established a system to quantify VSP of high sensitivity by using standard protein made by genetically transformed E. coli and specific antibody against VSP, and studied the relationship between VSP and GSD, by depod experiment and drought/excess wet experiments. The result of depod experiment with the cultivar 'Yukihomare' was the same with the previous studies, VSP accumulated much more than control and the syndrome of GSD appeared in soybean in depod treatment. Drought and excess wet had different impact on GSD. Excess wet caused GSD of the cultivar 'Tachinagaha (GSD susceptible)', while drought caused a little syndrome of GSD in the cultivar 'Touhoku 129 (GSD resistant)'. The accumulation of VSP differed between the two cultivars over time. In conclusion, the accumulation of VSP came along with the emergence of GSD. Different cultivars showed different response to drought and excess wet. In the future, it is expected that the dynamics of VSP will be elucidated in detail, leading to the development of early diagnosis technology for green stem disorder and the elucidation of mechanism of soybean GSD.