• Journal of Korean Society on Water Environment
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• v.28 no.5
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• pp.723-728
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• 2012

In this study, zeolites were synthesized by a fusion and a hydrothermal methods using a coal fly ash and a waste catalyst. The recovery performance of metal ions on the structure property of synthetic zeolites was evaluated as comparing the adsorption kinetics (Lagergen 2nd order model) and isotherm (Langmuir model) of $Co^{2+},\;Ni^{2+}$, and $Cu^{2+}$ ions. The synthetic zeolites (Z-C1 and Z-W5) were similarly assigned to XRD peaks in a reagent grade Na-A zeolite (Z-WK : $Na_{12}Al_{12}Si_{12}O_{48}\;27.4H_2O$). Adsorption rates of Z-W5 and Z-C1 were in the order of $Cu^{2+}\;>\;Co^{2+}\;>\;Ni^{2+}\;and\;Ni^{2+}\;>\;Cu^{2+}\;>\;Co^{2+}$, respectively. They had influenced upon structure properties of zeolite. Selectivities of metal ions and maximum equilibrium adsorption capacities, $q_{max}$, in Z-C1 and Z-W5 were in the order of $Ni^{2+}$ (127.9 mg/g) > $Cu^{2+}$ (94.7 mg/g) > $Co^{2+}$ (82.6 mg/g) and $Cu^{2+}$ (141.3 mg/g) > $Co^{2+}$ (122.2 mg/g) > $Ni^{2+}$ (87.6 mg/g), respectively. The results show that the synthetic zeolites, Z-C1 and Z-W5, are able to recover metal ions selectively in wastewater.

• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.459-465
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• 1997

The present study was undertaken to determine the effect of NT time on the rate of fusion a and suhseguent development In vitro and determine the optimal strength and duration of DC pulse for electrofusion of IVF donor embryo nuclei and IVM recipient oocytes. The recipient oocytes were enucleated 25 ~ 2Sh after IVM and further cultured for 18 ~ 20h prior to fusion for oocyte aging. IVF embryos as donor nuclei were C co cultured with BOEC for 16- to 32-cell stage development. The transfer time of donor bIas tomeres was 1~3h post-enucleation in early NT group and 1 ~ 18h post-enucleation in late NT group, respectively and fusion was performed 43~4Sh post-IVM. The fusion rate did not differ between the early NT and late NT group, but the rate of cleavage and 8- to 16-cell stage embryos in the late NT group was more higher than that in the early NT group. The fusion, cleavage and M+B development was high from O.7SkV /cm DC than from 1.0kV /cm DC voltage, resulting in 17.6% M+B from 0.75kV /cm DC voltage. No difference in fusion rate was among pulse durations, but 50 and 70 usec pulse duration showed slight high cleavage and M + B d development. The results indicate that the best NT time of IVF donor blastomeres into the enucleated oocytes was 42~44 post-IVM and the most suitable condition for electrofusion was a single 0.7SkV /cm DC voltage for SO~70$\mu$sec.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.1
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• pp.26-33
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• 2012

Phosphoric acid-doped poly (2,5-benzimidazole) (DABPBI) was prepared by condensation polymerization of 3,4-diaminobenzoic acid for high temperature proton electrolyte membrane fuel cells. The membranes were casted directly using a hot-press unit and characterized by fourier transform infrared spectroscopy, thermogravimetric analysis, conductivity measurement, scanning electron microscopy and tensile test. The proton conductivities of DABPBI are observed to be 0.062 and 0.018 $S{\cdot}cm^{-1}$ under 30 and 1% relative humidity, respectively at a temperature of $120^{\circ}C$ which is appreciably higher than that of Nafion 115 under similar conditions. The DABPBI membrane has demonstrated excellent thermo- mechanical properties and proton conductivity suggesting its suitability as a high temperature membrane.

• Journal of Embryo Transfer
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• v.15 no.3
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• pp.247-253
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• 2000

This study was undertaken to optimize enucleation and reconstitution methods for the production of cloned mice by somatic cell nuclear transfer Outbred ICR mouse oocytes at the metapahse- II stage were retrieved from female mice superovulated by PMSG and hCG. In Experiment 1, oocytes were enucleated in medium supplemented with cytochalasin B (CCB) of 3 levels (0, 7.5 or 15 $\mu\textrm{g}$/mL), and higher rate of encleation was obtained at 7.5 and 15 $\mu\textrm{g}$/mL than at $\mu\textrm{g}$/mL. In Experiment 2, oocytes enucleated in 7.5 $\mu\textrm{g}$/mL CCB-containing medium were reconstituted with different types of somatic cell by following methods; 1) cumulus cells by direct cell injection, 2) cumulus cells by electric fusion (1.25 kV/cm, 2 pulses for each 70 $mutextrm{s}$) or 3) STO cells by the electrofusion. Electrofusion of STO cells with enucleated oocytes yielded the greatest (P<0.05) rate of reconstitution without lysis (76%) than any other combinations. Although significant decrease in the rate of somatic cell introduction was found, the electrofusion of cumulus cells yielded better rate of reconstitution than direct injection (0 vs. 18%). In Experiment 3, the duration of electric stimulation for the fusion was changed to either 50 $mutextrm{s}$ or 90 $mutextrm{s}$, but no significant improvement of reconstitution efficacy was obtained. In conclusion, this study showed that ICR mouse oocytes could be used for the production of reconstituted oocytes and a fusion method of 1.25 KV/cm with 2 pulses using 570 cell was the optimal.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.10 no.1
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• pp.82-89
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• 2014

In this study, the metallurgical analysis and mechanical property measurement have been performed to investigate the effect of long-term thermal aging on the microstructural evolution in the fusion boundary region between weld metal and low alloy steel in dissimilar metal welds. A representative dissimilar weld mock-up made of Alloy 690-Alloy 152-A533 Gr. B was fabricated and aged at $450^{\circ}C$ for 2,750 hours. The microstructural characterization was conducted mainly near in a weld root region by using optical microscopy, scanning electron microscopy, transmission electron microscopy. And the mechanical properties were measured with Vickers microhardness test and nanoindentation method. A steep gradient was shown in the chemical composition profile across the interface between A533 Gr. B and Alloy 152. Type-II boundaries were found in weld side of DMW and the hardness was the highest at the narrow zone between Type-II boundary and fusion boundary.

• Journal of Korean Neurosurgical Society
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• v.44 no.4
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• pp.217-221
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• 2008

Objective : Although anterior cervical discectomy and fusion (ACDF) is the standard treatment for degenerative cervical disc disease, concerns regarding adjacent level degeneration and loss of motion have suggested that arthroplasty may be a better alternative. We have compared clinical and radiological results in patients with cervical disc herniations treated with arthroplasty and ACDF. Methods : We evaluated 53 patients treated for cervical disc herniations with radiculopathy, 21 of whom underwent arthroplasty and 32 of whom underwent ACDF. Clinical results included the Visual Analogue Scale (VAS) score for upper extremity radiculopathy, neck disability index (NDI), duration of hospital stay and convalescence time. All patients were assessed radiologically by measuring cervical lordosis, segmental lordosis and segmental range-of-movement (ROM) of operated and adjacent disc levels. Results : Mean hospital stay (5.62 vs. 6.26 days, p<0.05) and interval between surgery and return to work (1.10 vs 2.92 weeks, p<0.05) were significantly shorter in the arthroplasty than in the fusion group. Mean NDI and extremity VAS score improved after 12 months in both groups. Although it was not significant, segmental ROM of adjacent levels was higher in the fusion group than in the arthroplasty group. And, segmental motion of operated levels in arthroplasty group maintained more than preoperative value at last follow up. Conclusion : Although clinical results were similar in the two groups, postoperative recovery was significantly shorter in the arthroplasty group. Although it was not significant, ROM of adjacent segments was less in the arthroplasty group. Motion of operated levels in arthroplasty group was preserved at last follow up.

• Biomedical Science Letters
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• v.2 no.1
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• pp.21-30
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• 1996

MAP kinases are a family of serine/threonine specific protein kinases becoming activated in response to different proliferative stimuli by phosphorylation at both threonine and tyrosine residue. Present study shows that MAP kinase was purified from P388 murine leukema cells by SP sephadex C-50, phenyl superose and Mono Q column chromatography and identified with anti-ERKl antibody by western blotting. Immnublotting analysis to the crude extract of P388 cell lysate shows 44 kD and other minor bands but partial purified fraction eluted from phenyl supherose column have 44kD and 66 kD isoform. Subcloned GST-fusion protein from N-terminal of $p56^{kk}$ was tested as a substrate for MAP kinase phosphorylation. It was showed that the wild type and mutant forms(S42A) were fully phosporylated by purified MAP kinase fraction as com-pare with the other mutant form(S59A). This finding suggest that those GST-fusion proteins may be used as substrate for the in vitro test of MAP kinase.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.251-252
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• 2012

ITER(국제핵융합실험로) 제어시스템은 중앙제어와 Plant System으로 구성되며 CODAC, Central Interlock, Central Safety System으로 구분된다. 초전도자석에 전류를 공급하는 AC/DC 컨버터 시스템은 2상한, 4상한 구조의 전원 장치, 초기 플라즈마 발생에 필요한 Switching Network Unit, 코일에 저장된 에너지의 급속 방전을 위한 Fast Discharge Unit 및 무효 전력 보상장치로 구성된다. 4상한 전원장치는 1, 2, 4, 6대의 전원 장치가 직렬 접속되어 무효전력 발생이 최소로 하도록 제어된다. 대용량의 무효전력이 급격히 변화는 환경에서 계통 전압을 유지하기위해 무효전력보상장치는 각 전원 장치가 예측한 무효전력 값을 이용하여 제어한다. 본 논문은 ITER 전원 장치를 운전하기 위한 제어시스템의 개요와 예비설계 결과이다.

• Journal of Soil and Groundwater Environment
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• v.15 no.6
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• pp.72-80
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• 2010

Possibility of the usage of sludge generated in coal mine drainage treatments as a briquette additive was investigated by the combination of industrial, elemental, and combustion experiments. A series of briquettes having 2% and 6% of sludge were used for the experiments. Compared to the control sample, our results show that all experimental values for the briquettes are very similar. In particular, it is worthy to note that there is no obvious difference in calorific values for the briquettes containing 2% or 6% of sludge. The calorific values are 4,250~4,360 kcal/kg, 4,240~4,250 kcal/kg, 4,180~4,210 kcal/kg, and 4,270~4,360 kcal/kg for the control sample, briquette containing 6% of Hambaek sludge, briquette containing 6% of Hamtae sludge, and briquette containing 2% of Hambaek sludge, respectively. Results of ash fusion temperature show that the temperature is greater than $1,550^{\circ}C$ for the control sample. However, the temperature for the briquettes with 6% of Hambaek sludge and 2% of Hambaek or Hamtae sludge is $1,510^{\circ}C$. For a briquette containing 6% of Hamtae sludge, the temperature of ash fusion is $1,530^{\circ}C$. After combustion, environmental impacts of the briquettes with sludge were tested. Little environmental influence was observed for the combusted briquettes with sludge.

• The Korean Journal of Mycology
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• v.15 no.2
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• pp.80-86
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• 1987

The author isolated high cellulolytic fungi from natural sources and determined optimal condition of protoplast formation and fusion as fundamental step for improvement of the isolated it's cellulolytic ability. Three different cellulolytic fungi, such as Aspergillus sp., Penicillium sp. and Trichoderma sp., were isolated from soil. Their cellulolytic activities were compared with that of Aspergillus niger which was useful industrially and had cellulase activity. It was Aspergillus sp. that showed the highest activity of all these four fungi. And then it was followed by Penicillium sp., Trichoderma sp., and Aspergillus niger in order. An auxotrophic mutant of Aspergillus sp. was obtained by UV mutagenesis method. Having try to produce protoplast from mycelia, the author found that ${\beta}-glucuronidase$, at pH 6.0, was effective cell-wall lytic enzyme. And the optimal concentration of this enzyme was 5,000 unit/ml. Regeneration rates of wild type, met. auxotroph and arg. auxotroph, in presence of osmotic stabilizer, were 7. 0%, 7. 5% and 5.2%, respectively. PEG with M.W. 6,000 was effective stimulator for protoplast fusion in the concentration of 30% (W IV). In such a condition, we obtained 1.2% cell fusion rate.