• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.6
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• pp.328-334
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• 2000

A lithium ion secondary battery using carbon as a negative electrode has been developed. Further improvements to increase the cell capacity are expected by modifying the structure of the carbonaceous material. There are hopes for the development of large capacity lithium ion secondary batteries with long cycle, high energy density, high power density, and high energy efficiency. In the present paper, needle cokes from petroleum were examined as an anode of lithium ion secondary battery. Petroleum cokes, MCL(Molten Caustic Leaching) treated in Korea Institute Energy Research, were carbonized at various temperatures of 0, 500, 700, $19700^{\circ}C$ at heating rate of $2^{\circ}C$/min for lh. The electrolyte was used lM liPF6 EC/DEC (1:1). The voltage range of charge & discharge was 0.0V(0.05V) ~ 2.0V. The treated petroleum coke at $700^{\circ}C$ had an initial capacity over 560mAh.g which beyond the theoretical maximum capacity, 372mAh/g for LiC6. This phenomena suggests that carbon materials with disordered structure had higher cell capacity than that the graphitic carbon materials.

• Plant Resources
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• v.3 no.3
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• pp.163-172
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• 2000

We compared microstructural features of the ordered cell and disordered leaves in Citrus junos Sieb. by electron microscopy. In the cell of the ordered leaves, many chloroplasts and large vacuoles were particularly observed. Also a lot of vessel, companion cell and big nucleus were presented in vascular bundle regions. The mitochondria and the other organelles were interspersed among the chloroplasts in a thin, peripheral layer of cytoplasm. The chloroplast possessed typical grana and intergranal lamellae, numerous starch grains and a few small osmophilic globules. Besides, microbodies were closely associated with the mitochondria and the chloroplast. The process of the formation of the secondary cell wall from primary cell wall was observed the vessel elements, the tonoplast wall and the secondary cell wall. It was observed that the oil sac with the unique perfume distributed the adjacent cell wall. In the cell of disordered leaves, the all of the organelles were thrust toward the cell wall due to the fusion of vacuoles in the cells. It was observed that a lot of the very small particles spreaded in the cytoplasm. The loss of unique perfume of the leaves was resulted in the destruction of the oil sac. Also, there was not observed grana, lamellae, starch and osmophillic globules in the chloroplast. The small distributed organelles was not observed but the elongation of the cell wall was proceed no longer. Therefore, the plasma membrane diverged from the cell wall. All of organelles in the cell had poor function and deformation. A massive vacuole was fulfilled in single cell and the vacuole contains a lot of large and small particles. The organelles were presented on the side of the cell wall according to the enlargement of vacuole and they were observed to be breakdown.

• Biotechnology and Bioprocess Engineering:BBE
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• v.4 no.1
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• pp.12-16
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• 1999

Xenorhabdus nematophilus sp., an insect-pathogenic bacterium, was newly isolated from Korean entomopathogenic nematode of Steinernema carpocapsae, which can be used as a useful bioinsecticide. Primary and secondary form variants of Xenorhabdus nematophilus were observed when cultured in vitro. Primary form variants adsorbed bromothymol blue, while secondary form did not. However, many other characters of two variants were very similar. The variants were all rod-shaped and cell size was highly variable ranging from 0.5 by 2.0 ${\mu}$m to 1.0 by 5.0 ${\mu}$m. Both produced highly toxic substances and killed the insect larva within 20∼38 hr, indicating that insect pathogenicity of Xenorhabdus is not directly associated with its phase variation. In addition, cell-free culture supernatant of Xenorhabdus was sufficient to kill the insect larva by injecting it ito insect hemolymph; however, cell-harboring culture broth was more effective for killing the insect. The use of Xenorhabdus nematophilus may provide a potential alternative to Bacillus thuringiensis (Bt) toxins.

• Journal of Mechanical Science and Technology
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• v.15 no.8
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• pp.1188-1195
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• 2001

A numerical analysis has been carried out to investigate the influences of thermosolutal convection on the heat and mass transfer and solute segregation in crystals grown by the vertical Bridgman technique. The governing equations are solved by a finite-volume method using the power law scheme and the SIMPLE algorithm in which body-fitted coordinate system has been used. A primary convective cell driven by thermal gradients forms in the bulk of the domain, while a secondary convective cell driven by solutal gradients forms near interface. As the solutal Rayleigh number increases, secondary cell becomes to be stronger and has a great influence on the radial concentration along the interface.

• Current Photovoltaic Research
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• v.4 no.4
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• pp.155-158
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• 2016

Long-term stability of dye-sensitized solar cell (DSSC) module is critical for the commercialization. We investigated the effect of sealing technology on the long-term stability of the $10cm{\times}11cm$ sized DSSC modules. We applied the concept of secondary sealing to the module and then performed several stability tests such as humidity cycle, 1 sun light soaking and outdoor stability tests. The enhanced stability was confirmed for the DSSC module employing optimized sealing materials and architectures.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.27-33
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• 2011

HCPV(High Concentrated PV) systems have well known for CPV market all over the world. Low concentration type silicon based modules have been introduced in the market. But low cost of standard flat silicon modules made them useless nowadays. High cost of compound semiconductor solar cell reduced cost effective cpv module production than that of recently silicon solar cell. In order to overcome increasing cost of CPV module, we study middle concentration type fresnel lens simulation using concentrated type silicon based solar cell. Linear type fresnel lens made production of CPV module without secondary optics such as light pipe or light tunnel. This type of fresnel lens design makes more cost effective solution for cpv niche market.

• Journal of Medicine and Life Science
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• v.17 no.3
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• pp.103-106
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• 2020

Bone marrow failure, such as aplastic or myelophthisic anemia, can occur due to an underlying lymphoid malignancy and cause life-threatening events. A 58-year-old man diagnosed with angioimmunoblastic T-cell lymphoma had recently visited the emergency department because of an altered level of consciousness caused by acute severe anemia. The laboratory findings were strongly suggestive of bone marrow failure syndrome. Bone marrow examination was immediately performed and, subsequently, dexamethasone was initiated to control the underlying lymphoma. Intravenous immunoglobulin was also administered in combination due to combined immune hemolytic anemia and thrombocytopenia. Bone marrow examination revealed a packed marrow with marked fibrosis and lymphoma involvement. A diagnosis of secondary myelofibrosis related to the underlying lymphoma was made, and sequential combination chemotherapy was introduced despite the presence of severe anemia and thrombocytopenia. After combination chemotherapy, his hematologic profile and underlying lymphoma improved. Better understanding of various hematologic manifestations and knowledge of the rare condition of lymphoma are essential for appropriate diagnostic approaches and treatment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1B
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• pp.35-45
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• 2009

In this study, a laboratory experiment has been performed on a S-curved channel with two curved sections. In the experiments, effects of 3-D velocity structures on mixing characteristics of tracer material were investigated. As a result, it was clearly noticed that the primary flow travels taking the shortest course of the meandering channel and has a very ununiform distribution at the bends. The secondary cell which was developing at the first bend disappears at the crossover, and then, at the next bend, secondary cell is re-developing in the opposite direction. The experimental results show that mixing of tracer is significantly affected by the combined action of ununiform primary flow and secondary cell. The ununiform primary flow separates the tracer cloud in the longitudinal direction, and the secondary cell further separates the retarding tracer cloud mainly in the transverse direction. As a result, these complex flow structures cause separation and spreading of tracer cloud both in the longitudinal and in the transverse directions. The measured dimensionless transverse dispersion coefficients calculated using 2-D routing procedure ranges 0.012-0.875, and is generally proportional to width to depth ratio (W/h). The predicted values calculated by the theoretical equation overestimate slightly the measured transverse dispersion coefficients.

• Journal of Plant Biotechnology
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• v.5 no.3
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• pp.181-185
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• 2003

Callus and suspension cultures derived from leaf explants of Plumbago rosea were established on Murashige and Skoog's medium containing 1 mg/L IAA, 0.5 mg/L NAA and 0.3 mg/L BAP. Callus cultures were tested for their growth and accumulation of plumbagin, a naphthoquinone and was identified by $^1H$ NMR and electron ionization mass spectroscopy. While auxins (not 2,4-D) influenced growth and plumbagin accumulation, cytokinins did not influence them much. Increasing concentrations of IAA in presence of NAA and BAP increased plumbagin in suspensions only up to 1 mg/L. Growth of callus was optimum (8.3 g DCW/I) at a hormonal combination of 1.5 mg/L IAA, 0.5 mg/L NAA and 0.3 mg/L BAP, but high plumbagin accumulation (4.9 mg/g DCW) was recorded at 1.0 mg/L IAA plus 0.3 mg/L BAP. Since instability in growth and secondary metabolite accumulation was noticed, several cell lines/clumps of callus were screened for plumbagin accumulation by visual and analytical methods. Biomass and accumulation of plumbagin showed a negative correlation in several cell lines. But one cell line showed stability both in terms of biomass and plumbagin accumulation over a period of 6 months.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.61-67
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• 1983

Two cases of primary malignant lymphoma of the brain and six cases of secondary CNS lymphoma seen at Yonsei cancer center, radiotherapy department for recent 4 years are presented. Primary lymphomas revealed single tumor mass on corpus callosum area and secondary lymphoma were intracranial (3 cases) or leptomeningeal type (3 cases). Histology of primary lymphoma were reticulum cell sarcoma and secondary lymphomas were either diffuse histiocytic or diffuse poorly differentiated lymphocytic lymphoma. All patients showed good response to radiation. Two patients with primary CNS lymphoma and two of six secondary CNS lymphoma are alive after radiotherapy (34, 31, 26, 12 months). But the prognosis of secondary CNS lymphoma is grave, because of progressive systemic disease. Incidence, risk factors, diagnosis and therapeutic management of CNS involvement are also discussed.