• Bulletin of the Korean Chemical Society
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• v.20 no.6
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• pp.701-704
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• 1999

Metallophthalocyanines [PcM, Pc: phthalocyanine, M: Fe 2+ , Co 2+ ] were reacted with α-isocyanonaphthalene( α-in) and α-isocyanoanthracene (α-ia) to form monomeric complexes. The synthesis and coordination behaviour of the isocyanides as a ligand (L) are discussed. All the products were characterized by spectroscopic methods and instrumental analysis. The electrical conductivities of these complexes, which were not treated with dopant, were attributed to the metal-ligand electron delocalization in the PcML2 complexes. The complexes have an enlarged macrocycle where the π-electron back donating ability of PcM is stronger than the σ-electron coordinating ability of the isonitrile ligands. Their electrical conductivities were measured as σRT = 2.1×10 -9 ~3×10 -10 S/cm. Also thermal stability was investigated in this study.

• Korean Journal of Microbiology
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• v.45 no.3
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• pp.268-274
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• 2009

A photosynthetic cyanobacterium Arthrospira platensis, well known for health food supplement, was studied as a target species for atmospheric $CO_2$ removal as well as biomass production. Although the biomass of A. platensis was massively produced in many countries, the recovery cost of its biomass is still high. The purpose of this study was to develop the A. platensis mutant strains which have enhanced growth rate and floatation activity to reduce the recovery cost. A. platensis KCTC AG20590 was treated with 0.24% ethyl methanesulfonate (EMS) for 20 min at room temperature. The mutant strain A. platensis M20CJK3 was finally selected by its morphological and physiological features. The morphology of the mutant A. platensis M20CJK3 was changed from loose-coiled form to tight-coiled form showing short pitch. The growth and $CO_2$ uptake rate of A. platensis M20CJK3 were improved about 15% and 17% compared with A. platensis KCTC AG20590, respectively. The floatation activity of A. platensis M20CJK3 was enhanced in 2-fold compared with that of A. platensis KCTC AG20590. Soluble proteins extracted from two strains were analyzed by two dimensional electrophoresis (2-DE) and MALDI-TOF MS/MS. Among 15 protein spots induced in 2-DE analysis, two spots were the proteins related to photosynthesis and electron transfer system of the other cyanobacteria. As a consequence, it seems that the tight-coiled mutant A. platensis M20CJK3 has an advantage of high growth rate and floatation activity which are beneficial for the mass cultivation and recovery.

• Analytical Science and Technology
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• v.6 no.3
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• pp.313-318
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• 1993

The rose petal tissue biosensor has been constructed by immobilizing New carina rose tissue. Optimum conditions for the determination of urea were investigated using this sensor. Selectivity and life time of this sensor were also obtained. As a result, the biosensor showed the optimum response characteristics in 0.20M phosphate buffer solution at pH 8.0, $37^{\circ}C$ and 50mg of tissue amounts. This sensor was linear from $9.0{\times}10^{-5}$ to $4.0{\times}10^{-3}M$ urea with a slope of 42mV/decade. The limit of detection and response time are $7.0{\times}10^{-5}M$ and 17~19 min.

• Analytical Science and Technology
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• v.15 no.3
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• pp.214-220
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• 2002

The interfacial accumulation of the chromium-cupferron complex and the catalytic wave of its redox process is characterized by cyclic voltammetry. One cathodic peak is observed in the forward scan at -1.45 V. Scanning in the reverse direction produces a inverted peak at -1.39 V, which is indicative of a catalytic process. The optimal conditions of inverted peak were found to be 1 mM borate buffer solution(pH 9.48) containing $1{\times}10^{-4}M$ cupferron, holding potential of -1.8 V and scan rate of 20 mV/s. Using main peak, a preconcentration time of 1 min results in a detection limit of $3.2{\times}10^{-10}M$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.17 no.2
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• pp.53-58
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• 1981

Optical properties of sea water were studied in the northwestern water of Jeju Island, based on seven oceanographic stations in July, 1980. Submarine daylight intensity was measured at intervals of 5m depth in the upper 70m layer by using the underwater irradiameter(Kahlsico #268 WA360). The mean absorption coefficients of the sea water were appeared as 0.106(0.084-0.152), 0.135(0.106-0.184), 0.089(0.069-0.130) for clear, red, green, and blue color respectively. The transparency ranged from 11 to 19 meters(mean 16.1m). The mean water color in this area was 4.3(3-5) in Forel scales. The relation between absorption coefficient(k) and transparency(D) was k=1.66/D, k=2.12/D, k=1.38/D, and k=1.51/D for clear, red green, and blue color respectively. The rates of light penetration for clear, red, green, and blue color in four different depths were computed with reference to the surface light intensity respectively. The mean rates of light penetration in proportion to depths were as follows; clear : 56.57%(5m), 20.54%(15m), 4.60%(30m), 0.68%(50m). red : 50.14%(5m), 2.37%(30m), 0.23%(50m). green : 62.29%(5m), 26.43%(15m), 7.74%(30m), 1.56%(50m). blue : 59.29%(5m), 23.43%(15m), 6.10%(30m), 1.08%(50m).

• Korean Journal of Veterinary Service
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• v.17 no.3
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• pp.255-263
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• 1994

To elucidate the action of the adrenergic nerve on the isolated uterine smooth muscle of the pig, effects of electrical transmural nerve stimulation and norepinephrine were investigated on the pretreatment of phentolamine ； non-selective ${\alpha}$-adrenoceptor blocker, propranolol ; ${\beta}$-adrenoceptor blocker and the yohimbine；${\alpha}_2$-selective adrenoceptor blocker from physiograph. 1. The relaxation response induced by norepinephrine was the concentration of $10^{-6}$ M at first and maximum response was concentration of $10^{-4}$M. 2. The relaxation response induced by norepinephrine was not effected by the pretreatment with non-selective $\alpha$-adrenoceptor blocker, phentolanune ($10^{-6}$ M) but was completely blocked by the pretreatment with ${\beta}$-adrenoceptor blocker, propranolol($10^{-6}$ M). 3. The contractile response induced by electrical transmural nerve stimulation(20V, 10Hz, 0.5msec, 20sec ) was inhibited by the pretreatment with non-selective ${\alpha}$-adrenoceptor blocker, phentolamine($10^{-6}$ M) but was not inhibited and rather increased by the pretreatment ${\beta}$-adrenoceptor blocker, propranolol($10^{-6}$ M), and was not approximately effected by the pretreatment with ${\alpha}_2$-adrenoceptor blocker, yohimbine($10^{-6}$ M). These finding suggest that it was excitatory action by ${\alpha}_1$-adrenergic nerve and inhibitory action by ${\alpha}_2$-adrenergic, ${\beta}$-adrenergic nerve on uterine smooth muscle of the pig.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.154-160
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• 2000

Protease production and its characteristics were investigated with Bacillus subtilis PCA20-3 which was isolated from Korean traditional meju. The optimum culture conditions of Bacillus subtilis PCA20-3 for the production of the protease were as follow: 0.2% soytone, 2% starch, 0.1% $(NH_4)_2SO_4,\;0.2%\;CaCl_2,\;0.01%\;yeast\;extract,\;0.1%\; K_2HPO_4,\;0.1%\;KH_2PO_4,\;pH\;7.0,\;30^{\circ}C$ and 20 hrs. The optimum pH and temperature for enzyme activity of protease producing Bacillus subtilis PCA20-3 were pH 8.0-10.0 and $55^{\circ}C$, respectively. The enzyme was relatively stable at pH $6.0{\sim}11.0$ and at temperature below $50^{\circ}C$. The activity of the enzyme was inhibited by $Fe^(2＋)\;and\;Cu^(2＋)$. 2 mM phenymethanesulfonyl fluoride inhibited 89.2% of enzyme activity. This indicates that the enzyme is serine protease. The $K_m$ value was $5\;{\times}\;10^{-4}\;M,\;V_{max}\;value\;was\;100\;{\mu}g/min$. This enzyme hydrolyzed casein more rapidly than bovine serum albumin.

• Journal of Aquaculture
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• v.15 no.1
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• pp.1-6
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• 2002

Hydrological factors prevailing in the Namdae stream were as follows : temperature = -0.2~$26.8^{\circ}C$, salinity = 0.50~3.21$\textperthousand$, DO = 5.21~8.13 ppm, $PO_{4}-P$ = ND~1.37 ppm, $NO_{2-}$ = 0.10~0.81 ppm, COD = 1.53~2.82 ppm, $H_2 S$ = ND~0.0012 ppm and IL = 0.85~1.36 %. Sediment was typical, gravelly sand or sand with very good sorting value ranging from 0.53 to 1.77$\varphi$. Population density of the clam C. japonica ranged from 2 to 464/$m^2$. The clams were divided into four size classes, based on shell length of small (0~10 mm), medium (10~20 mm), large (20~30 mm) and largest (>30 mm), and were encountered at the frequency of 3.2, 50.4, 43.3 and 3.1 %, respectively.

• The korean journal of orthodontics
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• v.24 no.1 s.44
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• pp.17-35
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• 1994

Vanadium is an essential trace element but has not been identified with a specific biogical role. To study the direct effects of vanadium on osteoblast, we incubated murin osteoblast-like (MC3T3-El) cells with various corcentration of vanadium oxide & sodium orthovanadate. This study was designed to investigate the effect of vanadium on DNA synthesis, alkaline phosphatase (ALP) activity, cAMP formation responsive to parathormone(PTH) and type I $\alpha$ 2 collagen ribonucleic acid (mRNA) level in murin osteoblast-like (MC3T3-El) cells. The cells were cultured in $\alpha-minimal$ essential medium$(\alpha-MEM)$ supplemented with $10\%$ fetal bovine serum (FBS) and then changed to $0.1\%$ FBS with various concenoation of vanadium oxide & sodium orthovanadate. Quiescent cultured MC3T3-El cells incubated for 24 hours with 2,5,10,15,20 ${\mu}M$ vanadium oxide incorporated $[^3H]Thymidine;$ every concentration showed increases in $[^3H]Thymidine$ incorporations dose dependant manner, the greatest response occurred at $20{\mu}M$. Quiescent cultured MC3T3-E1 cells incubated for 3days with 2,5,10,15,20 ${\mu}M$ vanadium oxide, for 2days with sodium orthovanadate and alkaline phosphatase was assayed with disodium phenyl phosphate as substrate. Vanadium oxide increased the alkaline phosphatase content in MC3T3-El cells at $2{\mu}M\;&\;6{\mu}M$ ; the greatest response occurred at $2{\mu}M$. But decreased at other content sodium orthovanadate increased alkaline phosphatase content in MC3T3-El cells at all concenoation ; the greatest response occurred at $4{\mu}M$. Quiescent cultured MC3T3-El cells incubated for 3days with $5,10{\mu}M$ vanadium oxide , with $5,8{\mu}M$ sodium orthovanadate and cAMP formation was measured by Radioimmunoassay(RIA). Vanadium oxide & sodium orthovanadate showed the tendency of inhibitory effects on cAMP responsiveness to PTH in MC3T3-El cells. Quiescent cultured MC3T3-El cells incubated for 24hours with $10,20{\mu}M$ vanadium oxide, with $5,10{\mu}M$ sodium orthovanadate and Type I $\alpha$ 2 collagen ribonucleic acid (mRNA) expression was studied by Nothern blot analysis. Northern blot analysis of vanadium oxide treated cells showed decreasing effects 0& sodium orthovanadate revealed increasing effects in type I $\alpha$ 2 collagen ribonucleic acid (mRNA) level.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.378-383
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• 1989

For selection of mutants two rice varieties, Sangpungbyeo and Seomjinbyeo, were irradiated with 20 kR and 25 kR of gamma rays. One panicle per each plant was harvested in Ml, and single needling per hill was planted for M2 and M3 generations. Mutations for short culm, earliness and the major traits were examined. 1. The mutation rates were varied with the rice varieties and the doses of radiation, higher in Sangpungbyeo and 25kR than in Seomjinbyeo and 20 kR, respectively. 2. The rates in Sangpungbyeo with the 20 kR and 25 kR were 1.10％ and 1.47％. respectively and those of Seomjinbyeo were 0.51％ and 1.25％, respectively. 3. The culm lengths of short-culm mutants derived from Sangpungbyeo and Seomjinbyeo were reduced about 10％ compared to their mother varieties, especially it was possible to select the dwarf mutants reducing 57％ and 40％ of culm length in Sangpungbyeo and Seomjinbyeo, respectively with the dose of 25 kR irradiation. 4. The range of heading date of the mutant ion in the M3 generation was comparatively wide. Many earliness mutants shortened about 7 days were selected as compared with their mother varieties, some mutants of the irradiated group had early matured by 20 days and 30 days, respectively in both Seomjinbyeo and Sangpungbyeo.