• Microbiology and Biotechnology Letters
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• v.25 no.4
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• pp.346-353
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• 1997

During the screening of cellulase producing microorganisms, a fungal strain C-4 was selected from etiolated leaves. Based on taxonomic studies, the fungus could be classified as a strain of Trichoderma sp. When the strain C-4 was cultured in Mandels' media at 28$circ$C for 6 days, the enzyme activities detected in broth were as follows: 8.2 U/ml (28.1 U/mg) of CMCase activity, 0.75 U/ml (2.58 U/mg) of Avicelase activity, 1.67 U/ ml (5.68 U/mg) of $eta$-glucosidase activity. The optimum pH for enzyme induction was 6.2. The crude enzyme retained 100% of its original CMCase activity at 50$circ$C for 1 hr (pH 5.0), and at 4$circ$C for 24 hrs (pH 5.0). There was no effect on the CMCase activity in the presence of 1 mM of CsCl, LiCl, MgCl$_{2}$, and FeCl$_{2}$, respectively. When the crude enzyme was treated with trypsin and chymotrypsin (2% W/w) for 10 minutes, the remaining CMCase activity was 70%, but there was no further loss of activity for 60 minutes treatment at 30$circ$C. The crude enzyme showed the synergism with rumen fluid for the hydrolysis of Avicel and CMC by 118% and 130%, respectively.

• The Journal of Korean Society for Radiation Therapy
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• v.28 no.1
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• pp.57-64
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• 2016

Purpose : To evaluate the results of absorbed and effective doses using CBCT and 4D-CBCT settings for lung cancer. Materials and Methods : This experimental study. Measurements were performed using a Anderson rando phantom with OSLD(optically stimulated luminescent dosimeters). It was performed computed tomography(Lightspeed GE, USA) in order to express the major organs of the human body. Measurements were obtained a mean value is repeated three times each. Evaluations of effective dose and absorbed dose were performed the CL-IX-Thorax mode and Truebeam-Thorax mode CBCT. Additionally, compared Truebeam-Thorax mode CBCT with Truebeam-Thorax mode 4D-CBCT(Four-dimensional Cone Beam Computed Tomography) Results : Average absorbed dose in the CBCT of CL-IX was measured in lung 2.505cGy, heart 2.595cGy, liver 2.145cGy, stomach 1.934cGy, skin 2.233cGy, in case of Truebeam, It was measured lung 1.725cGy, heart 2.034cGy, liver 1.616cGy, stomach 1.470cGy, skin 1.445cGy. In case of 4D-CBCT, It was measured lung 3.849cGy, heart 4.578cGy, liver 3.497cGy, stomach 3.179cGy, skin 3.319cGy Average effective dose, considered tissue weighting and radiation weighting, in the CBCT of CL-IX was measured lung 2.164mSv, heart 2.241mSVv, liver 0.136mSv, stomach 1.668mSv, skin 0.009mSv, in case of Turebeam, it was measured lung 1.725mSv, heart 1.757mSv, liver 0.102mSv, stomach 1.270mSv, skin 0.005mSv, In case of 4D-CBCT, It was measured lung 3.326mSv, heart 3.952mSv, liver 0.223mSv, stomach 2.747mSv, skin 0.013mSv Conclusion : As a result, absorbed dose and effective Dose in the CL-IX than Truebeam was higher about 1.3 times and in the 4D-CBCT Truebeam than CBCT of Truebeam was higher about 2.2times However, a large movement of the patient and respiratory gated radiotherapy may be more accurate treatment in 4D-CBCT. Therefore, it will be appropriate to selectively used.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.844-852
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• 1997

In the polymerization of ethylene to produce crystalline polyethylene wax using the homogeneous titanium-based catalyst, the effects of various parameters such as catalyst, temperature, pressure, comonomer and time on the performance of catalyst and the properties of polyethylene wax were investigated. The properties of polyethylene wax obtained were characterized in terms of molecular weight, molecular weight distribution, crystallinity, density and morphology. Among the polymerization features with a series of mixed cocatalyst systems of $(C_2H_5)_3Al$, $(i-C_4H_9)_3Al$, $(C_2H_5)_2AlCl$ and $(C_2H_5)_3Al_2Cl_3$, it turned out that the combination of $(C_2H_5)_3Al$ and $(C_2H_5)_3Al_2Cl_3$ was more effective than any other combination. It was noted that the activity of catalyst and the properties of polyethylene wax were affected by the polymerization parameters, i.e. time, temperature and hydrogen partial pressure. The various kinds of crystalline polyethylene wax could be obtained by careful control of these parameters. Also we could obtain low density polyethylene wax which has density down to 0.91 g/cc by use of 1-butene as a comonomer.

• Journal of the Korean Ceramic Society
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• v.23 no.1
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• pp.27-32
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• 1986

This study is aimed at synthsizing high dielectric material (Ba, Sr)$TiO_3$ through direct wet process. Pure and ultra fine particle of (Ba, Sr)$TiO_3$ Powder was synthesized from $BaCl_2$ $SrCl_2$ and TiCl4 aqeous solution at KOH Solution in the $N_2$ gas atmosphere. $BaCl_2$ $SrCl_2$ and TiCl4 were Mixed with the mole ratio of 1:9, 3:7:10, 5:5:10, 7:3:10, 9:1:10 and sythesized at 4$0^{\circ}C$~9$0^{\circ}C$ for 10min~15hrs. The particle size particle shape crystallinity and synthesis condition of (Ba, Sr)$TiO_3$ powder with the variation of temperature and reaction time in the aqueous solution studied by the exprimental instruments of DTA. TGA, X-ray diffratometer SEM.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.255-258
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• 2002

In this study, $CeO_2$thin films were etched with an addition of $Cl_2$gas to $Ar/CF_4$gas mixing in an inductively coupled plasma(ICP) etcher. The surface reactions of the etched $_CeO2$thin films were investigated by X-ray photoelectron spectroscopy(XPS). It was analyzed that Ce peaks were mainly observed in Ce-O bonds formed $CeO_2$or $CeO_3$compounds. Cl peaks were detected by the peaks of Cl $2p_{3/2}$ and Cl $2p_{1/2}$. Almost all of Cl atoms were combined with Ce atoms like $CeCl_{x}$ compounds.

• Journal of the Korean Chemical Society
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• v.54 no.3
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• pp.269-274
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• 2010

The solubility and the physicochemical property (refractive index) in the NaCl-$CaCl_2$-$H_2O$ and KCl-$CaCl_2$-$H_2O$ systems were determined at $50^{\circ}C$ and the phase diagrams and the diagrams of physicochemical property vs composition were plotted. One invariant point, two univariant curves, and two crystallization zones, corresponding to sodium Chloride (or potassium chloride), dihydrate ($CaCl_2{\cdot}2H_2O$) showed up in the phase diagrams of the ternary systems. The mixing parameters ${\theta}_{M,Ca}$ and ${\Psi}_{M,Ca,Cl}$ (M = Na or K) and equilibrium constant $K_{sp}$ were evaluated in NaCl-$CaCl_2-H_2O$ and KCl-$CaCl_2-H_2O$ systems by least-squares optimization procedure, in which the single-salt Pitzer parameters of NaCl, KCl and $CaCl_2$ ${\beta}^{(0)}$, ${\beta}^{(1)}$, ${\beta}^{(2)}$ and $C^{\Phi}$ were directly calculated from the literature. The results obtained were in good agreement with the experimental data.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.141-147
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• 2015

Four halophilic bacteria were isolated from a salt water tank of more than 25% above salinity used for production of salt. HJS1 and HJS6 strains were identified as having ${\beta}$-glucosidase producing capabilities at high salinity. ${\beta}$-Glucosidase produced from these bacterial strains showed the best activity at 56-79 U/ml in NaCl (0-5%), showing the highest ${\beta}$-glucosidase activity at NaCl 3%. A salt tolerant ${\beta}$-glucosidase can maintain at least 75% activity of the enzyme in 0-20% NaCl concentration. The 16S rRNA gene sequences of strains HJS1 and HJS6 shows 99.8% similarity with Roseivivax roseus $BH87090^T$. Those sequences were registered as AB971835 and AB971836 in the NCBI GenBank. DNA-DNA hybridization test revealed that both strains showed 90.1 to 90.3% hybridization values with R. roseus $BH87090^T$, which was the closest phylogenetic neighbor. Major Cellular fatty acids of strains HJS1 and HJS6 were $C_{16:0}$, $C_{18:1}$ ${\omega}7c$, $C_{19:0}$ cyclo ${\omega}8c$ and 11-methyl $C_{18:1}$ and the major quinone was Q-10. Their fatty acid composition and quinone were very similar to Roseivivax roseus $BH87090^T$. Meanwhile, Roseivivax roseus $BH87090^T$ did not produce any ${\beta}$-glucosidase. Based on the molecular and chemotaxonomic properties, strains HJS1 and HJS6 were identified as members of Roseivivax roseus.

• Food Science and Preservation
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• v.5 no.1
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• pp.23-28
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• 1998

The objective of this study was to investigate the methods of quality maintenance using modified atmosphere packaging with various quality preservatives at ambient and low temperatures. Ethylene(<1.0ppm) accumulated during modified atmosphere storage of Chinese cabbage using polyethylene film(60$\mu\textrm{m}$) caused quality deterioration such as yellowing and abscission. The addition of potassium permanganate reduced ethylene level and thus extended storage life of l00% at 20$^{\circ}C$ and 140% at 0$^{\circ}C$. To establish the storage conditions of minimally processed sit and vegetables, the experiment was conducted with various quality preservatives and packaging materials. Ceramic film(Zeolite 7%, 60$\mu\textrm{m}$) showed increasing storage life of 50%, reducing total microbial counts of 50% and keeping high appearance quality of minimally processed pears stored at 20$^{\circ}C$ and 0$^{\circ}C$. Minimally processed Chinese cabbage treated with l% CaCl2 at 20$^{\circ}C$, and 1% CaCl2 and 1% NaCl at 0$^{\circ}C$ has a longer storage life of 90% with good maketable quality. Treatment of 1% NaCl for cut Asian penis appeared increased storage life of 100%, decreased cut surface browning and the best overall acceptability by a sensory panel.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.691-696
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• 2000

Syzygites megalocarpus occurred on the fruit bodies of Tricholoma matsutake, Leccinum rugosiceps, Pulveroboletus ravenelii, Russula emetica, and Amanita pseudoporphyria in the field. We could select Malt Extract Agar, Mueller Hinton Medium and Potato Dextrose Agar as optimal media among eight media. Syzygites megalocarpus showed an optimal temperature around $23^{\circ}C$ with optimal pH 6.0. Growth of S. megalocarpus on PDA was inhibited by 36.5% at 5% NaCl compared with without NaCl and did not grow at more than 8% NaCl in 2 days after inoculation. However, it grew 1.1 cm in 10% NaCl in 5 days after inoculation. Growth of Tricholoma matsutake on PDA was inhibited by increasing contration of NaCl and did not nearly grow at 2.5% NaCl in 60 days after inoculation. Because S. megalocarpus grew at high concentration of NaCl, we concluded that NaCl should not use for controlling S. megalocarpus on the fruit body of T. matsutake.

• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.96-101
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• 1989

The infrared multiphoton decomposition of trichloroethylene-H(TCE-H) and trichloroehtylene-D(TCE-D) was studied by using the high power $CO_2$ laser. The pressure dependence of TCE-H decomposition showed that the HCl elimination channel to form ClC ≡ CCl was the major step at high pressures, while the HC ≡ CCl formation step became important at low pressures. $Cl_2C$ = CHCl ${\rightarrow}$ (high pressure) ClC ${\equiv}$ CCl + HCl ${\rightarrow}$ (low pressure) HC ${\equiv}$ CCl + 2Cl${\cdot}$($Cl_2$) The IRMPD of TCE-H and TCE-D mixtures with 10P(20) laser line showed that optimum conditions of large isotope selectivity were the low system pressures and high laser powers. The experimentally observed dependence of the branching ratios on the pressure and laser fluence, and the isotope selectivity coefficients were quantitatively explained by using the modified energy grained master equations (EGME) model.