• 한국초지조사료학회지
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• 제2권2호
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• pp.16-20
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• 1981

To cultivate Dystaenia takesimana as a fodder crop, Its problems and solutions are summarized follows : 1. There are a wax layer and wings on the out side of seed coat of D. takesimana seeds, which seems to inhibit imbibition and cause delayed germination. 2. The root and shoot growth of D. takesimana are very poor in the early stage and weed control is quite troublesome. 3 The growth of D. takesimana is very poor the soil of low fertility and much depressed in summer. 4 . The percent germination could be increased by removing wings, soaking, high temperature treatment or by chemical scarification. 5. Compost is most effective for the growth of D. takesimana and lime dressing is desired in the soil of low pH. 6 . The seedling growth could be improved selecting and breeding the strains with better germination and root growth, at the germination and growth characteristics of D. takesimana are variable.

• Transactions on Electrical and Electronic Materials
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• 제5권4호
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• pp.153-157
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• 2004

ITO thin films were deposited on PET and soda-lime glass substrates by a dc reactive magnetron sputtering of In-Sn alloy metal target without substrate heater and post-deposition thermal treatment. The dependency of rf-bias voltage and substrate power during deposition processing was investigated to control the electrical and optical properties of ITO films. The range of rf bias voltage is from 0 to -80 V and the substrate power is applied from 10 to 50 W. The minimum resistivity of ITO film is 5.4${\times}$10$^{-4}$ $\Omega$cm at 50 W power and rf-bias voltage of -20 V. The best transmittance of ITO films at 550 nm wavelength is 91 % in the substrate power of 30 W and rf-bias voltage of -80 V.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.64-67
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• 2000

It is usual that the medical examination of human body need special knowledpe and equipments. Thus we have to spend Lime and energy on going to special place such as hospital where doctors and equipments are. Which often cause missing a good chance af medical treatment as well as giving us inconvenience. However many simple and convenient equipments were developed for checking our health conditions recently. O-ring test is accepted a3 one of useful methods to examine our heallb conditions. Also the test is recognized as a uscful means to judge, withoul any special equipment and medical knowledge, if some medical substances or foods are beneficial or harmful to our health. However, the judgement may be mcorrect because it depend on doctor's subjective point of view.In this study, we developed an automatic O-ring t a r mach~ne which enable us to check our health conditions objectively and quantitatively. The validity of the idea to develope the machine was proved by experiments.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.73-77
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• 2003

Red mud is a waste material formed during the production of alumina when the bauxite ore is subjected to caustic leaching. It is a brick-red colored highly alkaline (pH 10-12) sludge containing mostly oxides of iron, aluminum, titanium, and silica. Red mud, due to its high aluminum, iron, and calcium contents, has been suggested as a cheap adsorbent for removal of toxic metals (e.g., As, Cr, Pb, Cd) as well as for water or wastewater treatment. The basic advantage of red mud is its versatility in application. This study was conducted to evaluate the effect of red mud on stabilization and fixation of heavy metals (such as Pb, Cu, C $r^{6+}$, Cd, Zn) contained in the Al-coating sludge and soil. The results showed that the concentration of heavy metals leached from the treated sludge and soil was low, meeting the regulatory permit level.

• 한국환경과학회지
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• 제7권5호
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• pp.693-696
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• 1998

We tried to develope a desulfurization sorbent using eggshell for recycling, practicability, and economic development. The calcination character of the eggshell was examined by thermal gravimetric analysis and qualitative-quantitative character by X-ray diffractometer(XRD) and scanning electron microscope(SEM). The calcination was occurred easily in the case of eggshell and its form was changed from calcite($CaCO_3$) to lime(CaO). The grain and pore sizes of the calcined sample after base-treatment were larger and more crystallic. The adsorption ability of the eggshell was two- to six-times in the calcination temperature more than in the grain size. Therefore, the eggshell was thought to be usable as the desulfurization sorbent.

• 한국환경과학회지
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• 제25권1호
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• pp.23-29
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• 2016

This study has conducted greenhouse gas emission reduction test as using Oyster-shells originated PCC paper filler compare to non-Oyster shells used PCC. This examination was estimated and calculated in accordance with both IPCC (Intergovernmental Panel on Climate Change) and World Business Council for Sustainable Development (WBSCD). The greenhouse gas emission reduction estimation result indicates that, when oyster shells are recycled and used as paper filler, it reduces $27.97tCO_2\;per\;100\;ton$ of oyster shells. It is greenhouse gas emission $44.27tCO_2$ from PCC production changed to carbon emission reduction when replaced with oyster shell. LNG greenhouse gas emission $16.3tCO_2$ in relation to the pre-treatment with oyster shell per 100 ton is also reflected. As a result, it is assumed that roughly $0.2797tCO_2/oyster\;shell{\cdot}ton$.

• 한국세라믹학회지
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• 제25권6호
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• pp.665-670
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• 1988

The behavior of mechanical properties of ion exchanged glasses was investigated in this study. The used glasses were soda-lime-silica glasses that were produced by float process. The maximum values of the bending strength and the curvature depth are 45Kg/$\textrm{mm}^2$ and 8.6mm respectively treated at 45$0^{\circ}C$ for 6h, which are 4.4 times and 3.3 times higher than parent glass. In the case, the thermalshock resistance ΔT is 335$^{\circ}C$ that is 205$^{\circ}C$ higher than parent glass, which is the maximum values in this study. The maximum values of the surface microhardness is 490Kg/$\textrm{mm}^2$ in case of 43$0^{\circ}C$ for 4h. It is also found out that annealing points are increased linearly with increasing the amount of K+ ion exchange independent of treatment temperature. Furthermore, the present work shows that the ion exchange strengthened glasses are more effective than the physical tempering glasses ; the bending strength and the curvature depth are 1.8 times and twice higher respectively.

• 한국환경보건학회지
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• 제33권1호
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• pp.43-48
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• 2007

This study investigated the effects of pH, alkalinity, and chlorine ion which are important water quality impact factors to the corrosion in the simulated distribution system where the copper pipe is affixed. The result shows that pitting index was increased as the alkalinity and chloride ion increase in the distilled water, but there was no relation to pH. Actually the uniform corrosion rate was decreased as the pH increase with the laboratory tap water. In conclusion, it is necessary to control the pH which stands above minimum 7.5 to prevent pitting corrosion in the copper pipe. Consequently, comprehensive research about the effect of lime soda($Ca(OH)_2$) which was used as a coagulation additive in the water treatment plant to pipe corrosion must be accomplished additionally.

• 한국세라믹학회지
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• 제33권7호
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• pp.735-742
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• 1996

Antimony-doped Tin oxide (ATO) thin films were deposited on soda-lime glass substrates by DC magnetron sputtering technique. Effects of DC power film thickness and post heat-treatment on electrical conductivity of ATO film were investigated. Other properties of ATO film such as optical anti-chemical and wear properties were also reported in this work. The obtained ATO films showed electrical resistivities ranging from 5$\times$10-3 $\Omega$cm to 3$\times$10-3 $\Omega$cm with the average optical transparency above 80% in visible wavelength range and excel-lent anti-chemical properties where the electrical resistivity was not changed even after soaking the films in 1M HCl or 1M NaOH solution for 10 days. These properties were found to be related to the crystallinity of ATO film and the films having higher crystallinity showed better properties.

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1366-1370
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• 2001

Thin films of the SiO2-TiO2-PDMS composite material have been prepared by the sol-gel dip coating method. Acid catalyzed solutions of tetraethoxy silane (TEOS) and polydimethyl siloxane (PDMS) mixed with titanium isopropoxide Ti(OiPr) were used as precursors. The optical and structural properties of the organically modified 70SiO2-30TiO2 composite films have been investigated with Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible Spectroscopy (UV-Vis), Differential Thermal Analysis (DTA) and prism coupling technique. The films coated on the soda-lime-silicate glass exhibit 450-750 nm thickness, 1.56-1.68 refractive index and 88-94% transmittance depending on the experimental parameters such as amount of PDMS, thermal treatment and heating rate. The optical loss of prepared composite film was measured to be about 0.34 dB/cm.