• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.516-519
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• 2000

초임계 이산화탄소에 의한 동결 건조된 췌장내의 지질 추출 속도는 추출도, 추출압력, 초임계 이산화탄소의 유량, 원료의 입자크기에 의존하였고, 추출평형은 충진된 원료의 양에 대한 초임 계 이산화탄소의 유량에 비례하여 추출시간의 조절이 가능하였다. 초임계 처리된 원료와 수입 판크레아틴의 효소 역가 측정결과 수입원료에 비해 약 1.8배 이상의 높은 역가를 보였으며, 추출된 콜레스테롤 함량을 분석한 결과 용매추출을 한 경우는 약 2.1mg/g, 초임계 처리하였을 때에는 약 $2.2{\sim}3.1mg/g$정도 함유되어 있었다.

• Environmental Engineering Research
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• 제17권3호
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• pp.145-150
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• 2012

Pb-contaminated soil at a clay shooting range was analyzed by the sequential extraction method to identify metal binding properties in terms of detrital and non-detrital forms of the soil. Most of the metals in the soils existed as non-detrital forms, exchangeable and carbonate-bound forms, which could be easily released from the soil by a washing method. Therefore, the characteristics of Pb desorption for remediation of the Pb-contaminated soil were evaluated using hydrochloric acid (HCl) by a washing method. Batch experiments were performed to identify the factors influencing extraction efficiency. The effects of the solid to liquid (S/L) ratio (1:2, 1:3, and 1:4), soil particle size, and extraction time on the removal capacity of Pb by HCl were evaluated. Soil samples were collected from two different areas: a slope area (SA) and a land area (LA) at the field. As results, the optimal conditions at 2.8 to 0.075 mm of particle size were 1:3 of the S/L ratio and 10 min of extraction time for SA, and 1:4 of the S/L ratio and 5 min of extraction time for LA. The characteristics of Pb desorption were adequately described by two-reaction kinetic models.

• 한국물환경학회지
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• 제25권5호
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• pp.750-757
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• 2009

The ammonium ion exchange characteristics of natural zeolite were investigated to remove ${NH_4}^+-N$. The effect of water temperature, particle size and competitive cation on the exchange capacity was examined. Ammonium ion exchange capacity tended to decrease when the temperature increased from $25^{\circ}C$ to $40^{\circ}C$. Exchange capacity was increased according to the particle size of natural zeolite comes to be small. Batch isotherm experiments were conducted for measuring ammonium ion exchange capacity. The ion exchange capacity was well described either by the Langmuir isotherm model or by the Freundlich isotherm model. The ammonium ion exchange capacity ($q_m$) of zeolite carrier can be calculated $11.744mg-{NH_4}^+/g$-carrier. The ion exchange capacity of manufactured zeolite carrier was showed a similar tendency as ion exchange capacity of powder-sized natural zeolite. Therefore, zeolite carrier can be used for increasing of nitrogen removal efficiency in the wastewater treatment plants.

• 한국식품영양학회지
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• 제11권6호
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• pp.595-599
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• 1998

A batch experiment was conducted to evaluate the removal capacity of welsh onion(Allium fistulosum L.), shallot (Allium ascalonicum L.), garlic (Allium sativum L.) roots as an adsorbent for Ni and Pb in aqueous solution. One gram of the dried Allium root powder was reacted in 100ml of solution containing 10mg of each heavy metal and effects of metal concentration, pH, temperature, and size of adsorbent on the removal efficiency were evaluated. The results were as follows ; The amount of adsorption of heavy metal ions were higher with the smaller particles size of adsorbent. Garlic root was high adsorption capacity of Pb, especially. The higher concentration of heavy metal solution was, the more amount of adsorption of heavy metals was. The adsorption ratio was differed from a kind of heavy metal. As the temperature increased, the amount of adsorption of Ni and Pb by shallot and welsh onion were decreased. The amount of adsorption of Ni was high under alkali conditions but the amount of adsorption of Pb was high under neutral and acidity condition.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.302-305
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• 2002

Scoria is a bomb-sized, generally vesicular pyroclast that is red or black in color and light in weight. In this study, scoria from Cheju was examined for the use as a sorbent. It is composed of plagioclase, olivine, hornblende, pyroxene, and glass, with an average composition of 49.84% SiO$_2$, 14.07% A1$_2$O$_3$, End 9.14% Fe$_2$O$_3$. Studies on kinetic isotherm sorption of Zn(II) onto scoria under various parameters such as initial zinc concentration, particle size, and adsorbent/adsorbate ratio were carried out using an agitated batch. The results suggest that the smaller scoria size and the larger adsorbent/adsorbate ratio produce the higher degree of Zn(II) removal. More effective removal also appears at lower initial Zn concentration. The sorption behavior of Zn(II) onto scoria seems to be mainly controlled by cation exchange. Studies on equilibrium isotherm sorption of other heavy metals (Pb, Cu, Cd) onto scoria were also conducted and compared with those onto powdered activated carbon (PAC) and non-organic matter scoria (NOS), The results suggest that the Cheju scoria has the slightly higher sorption capability than PAC and NOS, and the order of the effective sorption onto scoria and PAC is Pb > Cu > Zn > Cd. The monometal sorption onto scoria is more stronger than the competitive sorption.

• 한국환경과학회지
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• 제21권5호
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• pp.623-631
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• 2012

The adsorption behavior of Eosin Y on activated carbon (AC) in batch system was investigated. The adsorption isotherm could be well fitted by the Langmuir adsorption equation. The kinetics of adsorption followed the pseudo-second-order model. The temperature variation was used to evaluate the values of free energy (${\Delta}G^{\circ}$), enthalpy (${\Delta}H^{\circ}$) and entropy (${\Delta}S^{\circ}$). The positive value of enthalpy change ${\Delta}H^{\circ}$ for the process confirms the endothermic nature of the process and more favourable at higher temperature, the positive entropy of adsorption ${\Delta}S^{\circ}$ reflects the affinity of the AC material toward Eosin Y and the negative free energy values ${\Delta}G^{\circ}$ indicate that the adsorption process is spontaneous. With the increase of the amount of AC, removal efficiency of Eosin Y was increased, but adsorption capacity was decreased. And adsorption capacity was increased with the decrease of particle size. With the increase of the amount of AC, removal efficiency of Eosin Y was increased, but adsorption capacity was decreased. And adsorption capacity was increased with the decrease of particle size.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.646-650
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• 1994

Aspergillus terreus NRRL 1960 was immobilized on various alginate gel beads, Celites, and polyurethane foam cubes, and the comparisons were made for the production of itaconic acid according to the types and sizes of each carrier. The levels of itaconic acid produced from Ca- alginate and Sr-alginate were similar, and the addition of bentonite to Ca- and Sr-alginate resulted in an increase of itaconic acid. The addition of 1.67% bentonite and 0.33% starch to Sr-alginate (SABS bead) produced higher level of itaconic acid (11.59 g/1) than other gel beads. A decrease in the size of Celite increased the itaconic acid production, and the smallest size of Celites, R- 634, produced 6.37 g/l of itaconic acid. Among various types of polyurethane foam cubes, HR 08 (2X2X2 cm) produced about 19 g/l of itaconic acid, which was more efficient than other carriers. In a repeated batch culture using immobilized cells on polyurethane foam cubes (HR 08, 2X2X2 cm), the stability of itaconic acid production was maintained up to 4 batches. Also, the possibility of itaconic acid production by continuous culture was shown in a packed-bed reactor.

• Toxicological Research
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• 제8권2호
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• pp.285-302
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• 1992

Human and rat hepatocytes were isolated by nonperfusion method and cultured for longer than 5 days. Human liver biopsy sample and rat liver were used as hepatocyte source. Several physical and chemical factors which were influencing on hepatocyte isolation procedure were examined and a batch isolation procedure was established for small size sample of rat liver. Isolated hepatocytes showed normal morphlologica characteristics in microscopy and electron microscopical examinations and a morphologica response to phalloidin. Isolated cells were cultured as a monolayer and proven to have intact morphological characteristics for longer than 15 days. Because human liver sample is harder and tighter compared with rat liver, a standard procedure for rat hepatocytes was slightly modified to reduce mechanical damage. Similarly with rat hepatocytes, isolated human hepatocytes showed a normal morphological characteristics and could be cultured for longer than 15days. Human and rat hepatocytes were examined on their functional integrities including cytochrome-P450 related enzyme activity and it's inducibility, hormonal inducibility of AIB uptake and TAT activity, albumin synthesis, DNA synthesis, cellular protein maintenance. In all parameters used in the present study, human and rat hepatocytes showed normal functional characteristics.

• 한국식생활문화학회지
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• 제15권3호
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• pp.155-162
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• 2000

The purpose of this study was to analyse serving size, plate waste, and sensory evaluation on menu of university foodservice. This study was conducted in three restaurant of one university for 14 days, 1995. The serving size of food was measured by weighing machine. The plate waste of food was calculated by the aggregative selective plate waste measurement technique. Questionnaires of sensory evaluation were developed and hand-delivered at three restaurants. Rating criteria of sensory evaluation were appearance, taste, temperature, color, flavor, texture and overall quality. The plate waste of side dish were 35.5%, 42.5%, and 39.2% in A, B, and C restaurants. The plate waste of kimchi were 46.8%, 36.3%, and 55.9% in A, B, and C restaurants. So, university foodservice manager should concern quality of side dish and kimchi. The score of fried food in sensory evaluation was low. So, batch cooking was needed. The score of rice in sensory evaluation of C restaurants was very low. Therefore, steam ice cooker in C restaurants should be changed by gas automatic rice cooker.

• 한국세라믹학회지
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• 제26권4호
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• pp.575-582
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• 1989

The effects of raw material feeding procedures and gelation temperatures on zeolite synthesis are investigated. Thus, the synthesis of zeolite 4A from sodium aluminate and sodium silicate solutions is chosen as a model reaction, for which equi-molar hydrogelation is performed with variation of feeding procedures and gelation temperatures. The formation of crystal nuclei, often being referred to as precursors, is induced under different conditions, the variation being examined by means of viscosity and water contents. The final products of zeolite 4A are evaluated by XRD, SEM morphology, particle size analysis and cation exchange capacity. Evidence shows that the viscosity of the initial products and their water contents are markedly influenced by the feeding methods of the reactant materials and by the gelation temperature. Further, it is found that the gelation at an elevated temperatures near 7$0^{\circ}C$ can be made possible through modification of mixing procedures. This provides convenient means of controlling the particle size of the final products. In this regard, a continuous flow-type mixing technique is proposed, which is demonstrated to be superior to the conventional batch-type mixings. The significance of this finding may lie in savings of equipment as well as energy costs, especialy on a large scale commercialization of zeolite production.