• Proceedings of the Korean Radioactive Waste Society Conference
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• 2016.05a
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• pp.61-62
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• 2016

우라늄전착물의 염 증류공정은 pyroprocess의 bottle neck에 해당되며, 회분식으로 조업된다. 본 발명에서는 증류탑 전단계에 고액분리실을 설치하고, 증류탑 후단에 냉각실을 설치하여, 전착물 도가니가 고액분리조- 증류조- 냉각조를 순차적으로 통과하여 조업시간을 크게 단축할 수 있도록 하였다. 또 도가니가 고온에서 이동할 수 있도록 중간에 고온 밸브를 설치하여 도가니가 다음 단계로 이동하면 새로운 전착물 도가니가 도입되어 연속적으로 조업이 가능하여 처리 용량이 향상되도록 하였다. 이에 따라 단위 시간당 처리용량을 현저히 높일 수 있다.

• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.299-308
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• 2016

This paper presents an investigation of the mechanical and microstructural properties on hardened samples that were synthesized using blended binder(fly ash(FA) and blast furnace slag cement(BFSC)), alkali activator and sea water or distilled water. Binders were prepared by mixing the FA and BFSC in different blend weight ratios of 6:4, 7:3 and 8:2. Sodium hydroxide and sodium silicate were used 5 wt% of binder, respectively, as an alkaline activator. The compressive strength and absorption were measured at the age of 3, 7 and 28 days, and the XRD, TGA and MIP tests were performed at the age of 28 days. An increase in the content of BFSC leads to an increase in the quantities of ettringite and C-S-H formed, regardless of the type of mixing water. And it also shows higher strength due to the reduction of pores larger than ~50 nm. All hardened samples in this study have common hydration products of C-S-H, $Ca(OH)_2$ and calcite. Hydrocalumite of all reaction products formed was only present in hardened sample mixed with sea water. For each FA/BFSC mixing ratio, the compressive strength of hardened sample mixed with sea water was similar to that mixed with distilled water. It is proposed that the slight increase of strength of samples mixed with sea water is mainly due to the presence of hydrocalumite phase containing chlorine ion, contributing to the change of total porosity and pore size distribution in samples.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.295-299
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• 2002

The esterification of alcohols with acetic acid, lactic acid and citric acid was carried out in batch during the second distillation. Effect of various parameters, e.g. pH of reactant base spirit, temperature of distillation, time of distillation were studied. The parameter of distillation temperature was modified by atmospheric distillation and pressure distillation. The pressure(1.9 atm.) distillation was used in order to react and distill at high temperature. Compared with the base spirit concentration, ethyl acetate, ethyl lactate and iso-amyl acetate in esterification distillate increased by 2,890%, 6,410% and 52%, respectively. Major factors of the esterification with organic acids in distilled spirit making were molecular weight of the organic acid and pH of reactant base spirit.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2619-2621
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• 2004

감마선 또는 x-선 등 방사선을 이용한 구조물 진단은 산업전반에 걸쳐 널리 이용되고 있다. 기존의 x-선이나 Ir-192의 감마선 등을 이용한 비파괴검사는 용접부의 확인이나 구조물의 내부 결점 확인과 같이 국부적인 진단에는 유용하나 석유화학산업에서 반응물의 분리 또는 정제 등에 많이 사용되고 있는 증류탑의 내부진단 실험에는 적합하지 않다. 증류탑은 목적에 따라 직경이 $3{\sim}10m$, 높이 $10{\sim}100m$에 달하는 대형 장치로서 내부의 이상현상에 대한 정확한 진단은 공정 전체의 가동효율 최적화에 결정적인 영향을 끼친다. 밀봉 감마선원으로부터 방출된 방사선의 투과율 변화를 증류탑의 반대편에 설치한 방사선 검출기로 측정하여 수직밀도분포(vertical density profile)를 구하여 증류탑의 내부현상에 대한 정확한 정보를 얻을 수 있는데 이러한 작업을 자동으로 수행할 수 있도록 한 것이 자동 증류탑 검사장치이다. 증류탑 진단장치는 크게 방사선 계측 및 데이터 전송회로, 방사선원부와 방사선검출부의 구동장치 및 구동회로, 데이터 수집 및 제어장치 둥으로 구성되어 있으며, 증류탑 검사를 자동화하여 진단결과의 신뢰도와 재현성을 향상시켰다. 본 논문은 방사선원과 방사선 검출장치의 위치를 자동으로 제어하면서 방사선 계측결과를 전송시키는 장치의 개발에 관한 내용으로서 개발된 장치의 소개와 산업현장 적용의 예를 소개함으로써 기존의 비파괴검사기술로는 진단할 수 없는 대형 증류탑의 진단에 효과적인 방사선 응용 계측장치임을 보이고자 한다.

• Korean Chemical Engineering Research
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• v.45 no.1
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• pp.39-45
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• 2007

This paper proposed a shortcut method for the structure design of dividing wall column based on the Fen-ske-Underwood equation by applying it on three conventional simple column configuration. It is shown that the proposed shortcut method can design the column structure including the feed tray, dividing wall section, and side-stream tray in a simple and efficient way in the initial design stage. Simulation study using HYSYS to compare the energy saving performance between the conventional sequential two column system and the dividing wall column designed by the proposed method shows that the proposed dividing wall column system saves from 16% to 65% more over the condepends on the composition of intermediate component while the optimal energy consumption pattern to internal flow distribution on the dividing wall section is characterized by the ESI factor of the feed mixture.

• Analytical Science and Technology
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• v.13 no.6
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• pp.712-721
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• 2000

$LiF-BeF_2-ZrF_4$(63-30-7 mol%) molten salt was dissolved up to 0.02g in 1ml of distilled water at room temperature. $ZrO_2$ oxide made from $ZrF_4$ through pyrohydrolysis was recovered by leaching in distilled water with $LiF-BeF_2-ZrF_4$molten salt including it at room temperature. The crystalline sharpness of recovered $ZrO_2$ oxide was not damaged.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.39-46
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• 2005

Though a fully thermally coupled distillation column-an energy efficient distillation system-consumes less energy, it is not widely implemented in practice due to its operational difficulty. A 3-column distillation system having improved operability is proposed here, and its energy saving performance and application related issues are investigated from the implementation result to a practical hexane process. When an energy integration is employed, the proposed system requires 18% less energy than a conventional 2-column system, which is found from the HYSYS simulation. Though more control loops than the 2-column system are required, the proposed system has better controllability of product compositions and the pressure control of the system is easier.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.1
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• pp.16-21
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• 2013

Nanofluids are suspensions of metallic or nonmetallic nano powders in base liquid and can be employed to increase heat transfer rate in various applications. In this research the heat transfer characteristics has been experimented by alumina(50 nm)/water nano-fluids. Experimental results showed that the increasing the concentration of alumina nanofluids local and average heat transfer coefficient increased. The local heat transfer coefficient of 6 Wt% nanofluid was increased 37~46% than water at X/D=50~120. The average heat transfer coefficient of 6 Wt% nanofluid was rapidly increased than water at Reynolds number 1100~1300.

• Journal of Life Science
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• v.20 no.7
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• pp.999-1004
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• 2010

Investigations were carried out on a $\beta$-glucosidase produced by Aspergillus niger under solid-state fermentation conditions as a model of enzyme recovery from fermented wheat bran. The leaching efficiency of distilled water to recover the enzyme from the fermented bran was higher than acetate buffer, citrate buffer, citrate-phosphate buffer and 5% methanol; thus, the conditions were further optimized with distilled water as the extracting agent. After fermented bran was washed three times with distilled water for 1.5 hr each under shaking conditions at 1:5 solid to solvent ratio, a maximum recovery of 0.025 U/g of wheat bran was obtained.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.1094-1103
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• 2017

The purpose of this study was to measure the bioactivity and antioxidant activity of seed from Gardenia jasminoides Ellis fructus (GJE). We determined tannin content ($1.517{\pm}0.003mg\;CE/g$, mg of catechin equivalents). The extraction yields of the GJE seed solvent were distilled water (DW) 36.61%, 70% methanol 30.10% and ethyl acetate (EA) 20.40%. The antioxidant activities of the extracts were significantly increased (0.2, 0.4, 0.6 mg/mL). Flavonoid contents (mg QE/g, mg of quercetin equivalents) were observed in the order of 70% methanol (0.799), DW (0.565) and EA (0.117). Antioxidant activities (DPPH, OH, ferrous ion-chelating capacity) were similar to the flavonoid content of each solvent. But ABTS scavenging activity and SOD like ability of DW extract were higher than 70% methanol extract. Comparing the yield and the antioxidant activity of each solvent of GJE seed, it seems to be preferable to use DW and 70% methanol solvent for extraction. As a result of this experiment, it has high antioxidant activity and physiological activity, which is expected to be highly valuable as a functional food and a natural antioxidant.