• 한국응용과학기술학회지
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• 제30권4호
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• pp.770-778
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• 2013

In this study, a liquid carbonation method was applied for producing precipitate calcium carbonate by liquid-liquid reaction. We recycled the recycling water of ready-mixed concrete, one of construction waste for use source of carbonate ion. A supernatant separated from the recycling water of ready-mixed concrete, as a result of ICP analysis of a cation, $Ca^{2+}$ was contained up to 1100 ppm. We used MEA as a $CO_2$ absorbent for the liquid carbonation. A precipitate $CaCO_3$ was produced at more than MEA 20 wt%. The precipitate $CaCO_3$ as a final product was separated and dried. The result of XRD was confirmed the generation of $CaCO_3$ to calcite structure.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1253-1256
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• 2007

A display device combining plasma display panel (PDP) and field emission display (FED) is proposed to achieve high luminous efficiency. The device can avoid the main energy loss channels of both PDP (ion loss) and FED (low CL efficiency). $2{\sim}6$”-diagonal test panels with carbon nano-tube (CNT) electron emitter and Xenon ambient gas showed the luminous efficiency of 4.14lm/W and brightness of $263cd/m^2$ at 35V (1kHz, 1% duty), indicating that it is a good candidate for the low voltage driven, highly efficient next generation display.

• Journal of Microbiology
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• 제35권2호
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• pp.134-140
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• 1997

Botrytis cinerea T91-1 has been shown to produce at least four different polygalacturonases into a liquid medium containing citrus pectin, a carbon sousrce. One of the enzymes, which had an apparent molecular weight of 66 kDa estimated by denatured polyacrylamide gel electrophoresis, was purified to electrophoretic homogeneity by a series of procedures including a cetone precipitation, ion exchange, heparin affinity, and reverse phase column chromatographies. The molecular weight of native enzyme was determined to be 64 kDa by gel permeation chromatography indicating the enzyme to be a single polypeptide chain. By viscometric analysis, the enzyme was revealed as exo-polygalacturonase. The enzyme activity was inhibited by divalent cations such as $Ca^{2+}$, $Mg^{2+}$, and Cu$^{2+}$. Km and Vmax for polygalacturonic acid hydrolysis were 0.33 mg/ml and 28.6 nM/min, respectively. The optimum temperature for enzymatic activity was 5$0^{\circ}C$. And the enzyme showed optimal pH values between 4.0 and 5.0. The enzyme was stable upto 12 hours in the range of pH 3 to 8 and at temperature below 3$0^{\circ}C$.

• 미생물학회지
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• 제15권3호
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• pp.123-130
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• 1977

In previous paper, it was reported that antibiotic substance such as tetracycline and streptomycin were produced by S'. albus subsp. and S'. globosus. And increase of mycelial growth of two strains, antibiotic production, and changes of pH range are extended to approximately 110-130 hrs in fermenting medium, there-after they decreased with culture period exception of pH range. Two Streptomyces spp. required commonly 4-5% starch as carbon sources and 1.5-2.0% soybean meal as nitrogen sources. However, 0.005-0.01M potassium phosphate dibasic, calcium carbonate (6mg/ml in S.albus subsp. and 2mg/ml in S. globosus), 0.01-0.03M, magnesium sulgate and 0.01M ferric chloride showed as optimal concentration for the growth of 2 strains. Mineral compoments such as zinc, manganese, cobalt, sodium and copper at the level of 10/sup -4/ -10/sup -6/M were observed. Especially, zinc ion showed toxicity to the growth of 2 strains at 0.005M. In relation with pH, there is a little difference in mycelial growth with cultural initial pH.

• 한국세라믹학회지
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• 제31권2호
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• pp.206-212
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• 1994

Effects of the film deposition process parameters on the properties such as deposition rate, etch rate, refractive index, stress and step coverage of plasma enhanced chemical vapor deposited (PECVD) tetraethylorthosilicate glass (TEOS) SiO2 film were investigated and analysed using SEM, FTIR and SIMS techniques. Increasing TEOS flow or decreasing O2 flow increased the deposition rate and the compressive stress of the oxide film but produced a less denser film. The deposition rate decreased owing to the decrease in the sticking coefficient of the TEOS and the O2 molecules onto the substrate Si with increasing the substrate temperature. Increasing the substrate temperature produced a denser film with a lower etch rate and the higher refractive index by lowering SiOH and moisture contents. Increasing the rf power increases the ion bombardment energy. This increase in energy, in turn, increases the deposition rate and tends to make the film denser. No appreciable changes were found in the deposition rate but the refractive index and the stress of the film decreased with increasing the deposition pressure. The carbon content in the plasma TEOS CVD oxide film prepared under our standard deposition conditions were very low according to the SIMS analysis results.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.417-420
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• 2002

A strong fibrin-specific fibrinolytic enzyme was produced from Bacillus subtilis KH-4 isolated from Deonjang, a Korean fermented soybean paste similar to Japanese miso. The addition of glucose as a carbon source resulted in the highest levels of caseinolytic and fibrinolytic activities. Likewise, the addition of yeast extract as the nitrogen source resulted in the highest caseinolytic and fibrinolytic activities (3473.2 unit and 47.4 munit, respectively), It was observed that out of all metal ion sources only calcium (chloride) enhanced caseinolytic and fibrinolytic activities, with increases of 4949.3 unit and 58.2 unit/mg, respectively. The optimal temperature for the production of the enzyme was found to be 4$0^{\circ}C$ in the optimal medium (glucose 20 g, yeast extract 5 g, CaCl$_2$l g, and NaCl 2 g). The maximum fibrinolytic activity was observed at the late stationary phase. B. subtilis KH-4 produced a fibrinolytic enzyme at 4$0^{\circ}C$, after 30 h growth, which increased up to 54 h and then remained constant. These results suggest that Deonjang has potential as a source of physiologically active anti-thromotic enzymes.

• 전기학회논문지
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• 제65권4호
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• pp.617-621
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• 2016

In addition to the energy storage facilities based on high power technologies, Electric double layer capacitors(EDLC) are today's candidate for power quality stabilization. However, its low energy density is often inhibiting factor for application of electric power industry. Hybrid supercapacitor is an promising energy storage device that positioned between conventional EDLC and Li-ion battery. This paper describes the preparation and characteristics of a hybrid supercapacitor and module for power quality stabilization. A cylindrical 3200F hybrid supercapacitor ($60{\times}74.5mm$) was assembled by using the $Li_4Ti_5O_{12}$ electrode as an anode and activated carbon as a cathode. It shows 2.5 times higher energy density than conventional EDLC with the same volume. In order to determine the characteristics of the hybrid supercapacitor Module for uninterruptible power supply (UPS), hybrid supercapacitor cells were connected in series with active balancing circuit. At even the high current density of 14A(10C), Module prepared by 18 cells showed the capacitance of 170F at 30~50V, suggesting the applicability for UPS.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.438-444
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• 2003

A new method to measure residual stress in micron and nano scale films is described. In the theory it is based on Linear Elastic Fracture Mechanics. And in the techniques it depends on the combined capability of the focused ion beam (FIB) imaging system and of high-resolution digital image correlation (DIC) software. The method can be used for any film material (whether amorphous or crystalline) without thinning the substrate. In the method, a region of the film surface is highlighted and scanning electron images of that region taken before and after a long slot, depth a, is introduced using the FIB. The DIC software evaluates the displacement of the surface normal to the slot due to the stress relaxation by using features on the film surface. To minimize the influence of signal noise and rigid body movement, not a few, but all of the measure displacements are used for determining the real residual stress. The accuracy of the method has been assessed by performing measurements on a nano film of diamond like carbon (DLC) on glass substrate and on micro film of aluminum oxide thermally grown on Fecrally substrate. It is shown that the new method determines the residual stress ${\sigma}_R=-1.73$ GPa for DLC and ${\sigma}_R=-5.45$ GPa for the aluminum oxide, which agree quite well with ones measured independently.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.199-201
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• 2002

Cancer therapy using high-energy $^{12}$ C ions is successfully under way at HIMAC, Japan. An alternative beam to $^{12}$ C is $^{11}$ C ions. The merit of $^{11}$ C over $^{12}$ C is its capability for monitoring spatial distribution of the irradiated $^{11}$ C by observing the $\beta$$^{+}$ decay with a good position resolution. One of the several problems to be solved before its use for therapy is the amount of nuclear interaction that deteriorates the dose concentration owing to the Bragg curve. Utilizing the dedicated secondary beam course for R&D studies at HIMAC, we measured the total energy loss of $^{11}$ C ions in a scintillator block that simulates the soft tissue in human bodies. In addition to the total absorption $^{11}$ C peak, non-negligible bump-shaped contribution is observed in the energy spectrum. The origin of the bump contribution can be nuclear interaction of the incident $^{11}$ C ions with hydrogen and carbon atoms. Further studies to reduce the ambiguity in dose distribution are mentioned.

• 공업화학
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• 제24권4호
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• pp.337-343
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• 2013

멤브레인 반응기는 멤브레인과 반응기를 결합하여 반응과 분리의 단위공정을 하나로 결합함으로써 전체공정을 단순화하고 반응효율을 높이고자 하는 혁신 기술로써, 멤브레인을 이용한 생성물의 선택적 제거를 통해 열역학적 평형을 뛰어넘는 전환율, 부반응물 생성 억제에 의한 반응 효율 및 선택성을 향상시킬 수 있다. 특히 이온전도성 세라믹을 이용한 멤브레인 반응기는 연료전지의 개발, 고순도 산소/수소의 분리/정제, 이산화탄소의 전환 및 다양한 화학제품제조에 까지 응용될 수 있기 때문에 시장의 확대와 더불어 크게 발전할 수 있을 것으로 기대된다. 본 총설에서는 수소이온 전도성 세라믹 멤브레인 반응기에 대한 연구동향과 다양한 응용분야 및 향후 전망 등에 고찰해 보고자 한다.