• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.115-122
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• 2010

In this study, the removal of Cs and Tc from a simulated fission products (FP) solution which were co-dissolved with U during the oxidative-dissolution of spent fuel in a mixed carbonate solution of $(Na_2CO_3-NaHCO_3)-H_2O_2$ was investigated by using a selective precipitation method. As Cs and Tc might cause an unstable behavior due to the high decay heat emission of Cs as well as the fast migration of Tc when disposed of underground, it is one of the important issues to removal them in views of the increase of disposal safety. The precipitation of Cs and Re (as a surrogate for Tc) was examined by introducing sodium tetraphenylborate (NaTPB) and tetraphenylphosponium chloride (TPPCl), respectively. Precipitation of Cs by NaTPB and that of Re by TPPCl were completed within 5 minutes. Their precipitation rates were not influenced so much by the temperature and stirring speed even if they were increased by up to $50^{\circ}C$ and 1,000 rpm. However, the pH of the solution was found to have a great influence on the precipitation with NaTPB and TPPCl. Since Mo tends to co-precipitate with Re at a lower pH, especially, it was effective that a selective precipitation of Re by TPPCl was carried out at pH of above 9 without co-precipitation of Mo and Re. Over 99% of Cs was precipitated when the ratio of [NaTPB]/[Cs]>1 and more than 99% of Re, likewise, was precipitated when the ratio of [TPPCl]/[Re]>1.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.02a
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• pp.245-256
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• 2004

The extraction of three kinds of amido podands, N,N,N'N'-tetrabutyl-3-oxa-pentanedi- amide (TBDGA), N,N,N'N'-tetra-isobutyl-3-oxa-pentanediamide(TiBDGA) and N,N,N'N'-tetra- butyl-3,6-dioxa-oct-anediam- ide(TBDOODA) on U(VI),Pu(IV), Am(III), Eu(III) and other metal ions is studied in nitric acid solutions. 40%octanol-kerosene is chosen as diluents to eliminate third phase and emulsion. TBDGA and TiBDGA show extraction selectivity to An(III) and Ln(III) much higher than to U(VI) and Pu(IV). Fe, Ru and Mo is poorly extracted by the three kinds of amid podands in 2~3mol/L $HNO_3$ solutions. Aiming to eliminate interface crude when using simulated HLLW solution in the system of 0.2mol/L TBDGA/Octanol＋kerosene, acetohydroxyamic acid was adapted. Distribution ratio of zirconium was decreased when adding acetohydroxyamic acid in aqueous solution, and interface crude disappeared as mixing extractant with HLLW. The counter-current extraction test is carried out in a set of miniature mixer-settler, with 0.2mol/L TBDGA/ 40% octanol-kerosene as extractant to separate U(VI), Pu(IV), Am(III) and Eu(III) from simulated high level liquid waste(HLLW) solution. In battery A, lanthanides and actinides are coextracted into organic phase with the recovery of 99.98% for U(Ⅵ), >99.99% for Pu(IV), and >99.99% for Am(III) and Eu(III) respectively. In battery R1, 99.99% U, 86.2% Pu and a part of Am or Eu are stripped into aqueous phase by 0.2mol/L acetohydroxyamic acid (AHA) in 0.01mol/L $HNO_3$ solution. In battery $R_2$, Am, Eu and remained Pu are completely back-extracted by 0.2mol/L AHA. This separation process contains no salt reagent, and it is not necessary to dilute HLLW feed.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.239-245
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• 1998

The feasibility of enzymatic hydrolysis of cellulosic materials is dependent on the cost of cellulase, which is strongly influenced by the selection of proper carbon source in the cellulase production medium. When solka floc was used as a carbon source for the production of cellulase by Trichoderma reesei Rut C-30, a maximum of 53.2 U/ml of CMCase activity (4.8 U/ml of FPase activity) was obtained with a concentration of 1 % of solka floc. The cellulase activity decreased to 50% in the presence of 0.5% of glucose in the medium. The production of cellulase was considerably enhanced when solka floc and wheat bran were used together as a carbon source. A medium which contained 1 % of solka floc and 3 % of wheat bran yielded highest cellulase activity: CMCase activity of 76 U/ml and FPase activity of 12.5 U/ml.

• Korean Security Journal
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• no.38
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• pp.33-56
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• 2014

This study is aim to make use of prevention of air terrorism and strengthen of air security in Korea. To achieve it. searching main feature in U.S aviation profiling. Aviation profiling in U.S used to Secure Flight, Screening Passengers by Observation Technique, Registered Travel Program. Through U.S Aviation Profiling, Prevention of air terrorism in Korea are as in the following. First, Through U.S Aviation Profiling, Information of terrorism constructed in advance and unification of constructed information. Second, Identifiying that institution exclusively for prevention of air terrorism. Third, Identifiying that human rights and privacy invasion to a minimun plan anout U.S aviation profiling. Finally, Identifiying that the spread of research development for prevention of air terrorism and strengthen of air security in Korea.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.114-116
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• 2008

Head-space method를 이용하여 살충제에 대한 VOCs의 배출특성을 평가한 결과 모든 제품에서 다양한 VOCs가 검출되었으며, 제품에 따라 다소 차이는 있지만 대부분의 생활용품에서 유해한 오염물질이 검출되었다. 국내 제조회사나, 동일제품의 종류, 제품의 형태에 따라 VOCs의 종류가 유사한 것도 있지만, 대부분 배출특성의 차이가 있을 수 있다고 사료되어진다.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.575-580
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• 1998

Cellulase production by batch culture using the Trichoderma reesei Rut C30 strain with various concentrations of Solka Floc with 1 % wheat bran was studied in a 2.5 I fermenter. The cellulase activity increased with Solka Floc concentration up to 5%. When 5% Solka Floc and 1% wheat bran were contained in the medium, carboxymethyl cellulose (CMC) and filter paper (FP) activities were 232.4 U/$m\ell$ and 21.25 U/$m\ell$, respectively. The productivity was 143.6 FPU $1^{-l}h^{-1}$ and the yield was 425 FPU/g. The colonial morphology of T. reesei Rut C30 grown on Avicel agar plates and the changes in mycelial morphology of T. reesei Rut C30 with culture time are also presented.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.11a
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• pp.311-312
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• 2009

가압 경수로에서 53,000 MWd/tU으로 연소된 사용후 핵연료의 PCI 영역에 대해 방사선 차폐형 성분 분석기기( Shielded EPMA)를 사용하여 반경방향에 대한 성분분포를 분석하였다. PCI 영역에서 산화층의 두께는 13um 이었으며, 핵분열생성물의 침투 두께는 시료에서 약 10 um 이내로 나타났다. 이 두께에 침투된 핵종의 총 농도는 1~2 wt%로 관찰되었다. 주요핵종은 Cs 0.5~0.7 wt%, Mo 0.2~0.3 wt%, Pd, Ru, Nd, Ce등이 0.1~0.2 wt% 로 관찰되었다.

• Bulletin of the Korean Mathematical Society
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• v.43 no.3
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• pp.531-541
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• 2006

[ $C\u{a}dariu$ ] and Radu applied the fixed point method to the investigation of Cauchy and Jensen functional equations. In this paper, we adopt the idea of $C\u{a}dariu$ and Radu to prove the Hyers-Ulam-Rassias stability of the quadratic functional equation for a large class of functions from a vector space into a complete ${\gamma}-normed$ space.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.504-507
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• 2000

Enzymatic hydrolysis of cellulose was studied with emphasis on the effect of cellulase loading and pulp sludge concentration on glucose yield. Enzyme loading appeared to have a significant effect on glucose yield. Chemical pretreatment had no effect on enzymatic hydrolysis of pulp sludge. High glucose yield was obtained from enzymatic hydrolysis, especially at sludge concentrations lower than twenty percent. The optimum concentrations of crude cellulase and ${\beta}-glucosidase$ were 5 U/mL and 8 U/mL, respectively, considering the amount of enzymes used and glucose produced.

• Journal of Periodontal and Implant Science
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• v.24 no.3
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• pp.607-617
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• 1994

To determine the effect of tenascin on forming periodontal pocket and pseudopocket, the ginival tissues were surgically obtained from the patients with adult periodontitis(10) and non-inflammatory phenytoin-associated gingival hyperplasia(5). The excised tissue specimens were fixed in neutral formalin for $6{\sim}24$ hours, embedded with paraffin, sectioned at 4-6m in thickness, mounted on glass slides coated with 3-aminopropyltriethoxysilane(Sigma Chemical Co., St. Louis, MO, U.SA.) and immunohistochemically processed by Avidin-Biotin peroxidase complex method for the localization of tenascin, using monoclonal mouse anti-human tenascin antiboday(Chemicon-International Inc., Temecula, CA, U.S.A., 1: 5,000) as the primary antibody. Regardless of periodontal pocket and pseudopocket, tenascin was localized along the connective tissue subjacent to basement membrane of gingival epithelium, and strong positive reactivity was obviously noted in the papillary projections of gingival connective tissue. The results suggest that tenascin may affect the development of papillary projections and the proliferation of epithelial cells.