• Title/Summary/Keyword: 불완전합성

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FABRICATIO0N OF NASICON ELECTROLYTES

  • Choi, Soon-Don;Park, Jung-Woo
    • Journal of Sensor Science and Technology
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    • v.4 no.1
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    • pp.35-42
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    • 1995
  • Conventional ball-milling technique was used to synthesize NASICON powders. The NASICON powders were made from three kinds of component powders : coarse($ZrO_{2}$, $Na_{3}PO_{4}$, $SiO_{2}$), fine ($ZrO_{2}$, $Na_{3}PO_{4}$, $SiO_{2}$) and fine ($ZrSiO_{4}$, $Na_{3}PO_{4}$) powders. The fine component powders were easily reacted to form the desired product at $1100^{\circ}C$ or higher, whereas incomplete reaction due to the coarse component powders occurred even at $1170^{\circ}C$. The finer the grain size of the starting powders was, the higher the bulk density of NASICON electrolyte after sintering was observed. Almost single phase NASICON electrolytes with more than 95% of the theoretical density, $3.27g/cm^{3}$, could be fabricated by sintering for $40{\sim}60$ hours at temperatures between 1150 and $1170^{\circ}C$.

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Multi Characters Detection Using Color Segmentation and LoG operator characteristics in Natural Scene (자연영상에서 컬러분할과 LoG연산특성을 이용한 다중 문자 검출에 관한 연구)

  • Shin, Seong;Baek, Young-Hyun;Moon, Sung-Ryong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.18 no.2
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    • pp.216-222
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    • 2008
  • This paper proposed the multi characters detection algorithm using Color segmentation and the closing curve feature of LoG Operator in order to complement the demerit of the existing research which is weak in complexity of background, variety of light and disordered line and similarity of left and background color, etc. The proposed multi characters detection algorithm divided into three parts : The feature detection, characters format and characters detection Parts in order to be possible to apply to image of various feature. After preprocess that the new multi characters detection algorithm that proposed in this paper used wavelet, morphology, hough transform which is the synthesis logical model in order to raise detection rate by acquiring the non-perfection characters as well as the perfection characters with processing OR operation after processing each color area by AND operation sequentially. And the proposal algorithm is simulated with natural images which include natural character area regardless of size, resolution and slant and so on of image. And the proposal algorithm in this paper is confirmed to an excellent detection rate by compared with the conventional detection algorithm in same image.

Biochemical Studies on the Major hemolymph Proteins (MHPs) of the Silkworm, Bombyx mori (누에 체액주단백질에 관한 생화학적 연구)

  • 성수일
    • Journal of Sericultural and Entomological Science
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    • v.28 no.1
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    • pp.30-36
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    • 1986
  • Polyacrylamide gel electrophoresis and autoradiography were applied to investigate the developmental profiles of the major hemplymph proteins (MHPs) and their biosynthesis. In addition, some biochemical methods were also used to isolate and purify the MHPs. The obtained results are summarized as follows. 1. MHP-a began to appear from the 2nd day of the fourth-instar larva while MHP-b and -c were detected first on the 1st day of the fifth-instar larva. All these proteins, however, showed a drastic increase in concentration at the 2nd day of the fifth-instar larva. 2. MHP-b and -c were synthesized in fat body on early day of the fifth-instar larva, but the possibility of MHP-a synthesis in fat body was excluded. 3. MHP-b was isolated and purified by heat-treatment (6$0^{\circ}C$), gel filtration on Sephadex G-100 and column chromatography on DEAE-cellulose and CM-cellulose. Purified MHP-b showed a single band on polyacrylamide gel- and SDS-polyacrylamide gel electrophoresis.

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REM Sleep and Memory (렘 수면과 기억)

  • Yang, Chang-Kook
    • Sleep Medicine and Psychophysiology
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    • v.3 no.1
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    • pp.15-24
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    • 1996
  • After rapid eye movement(REM) sleep was idenified in 1953, a lively interest developed concerning a possible role of this kind of sleep in memory processes. The author reviewed studies relating REM to memory/learning. Many studies in animals and humans gave substantial evidence for relating REM sleep to memory function. The evidence supporting the position taken in this paper comes from experiments showing that : (1) learning session is followed by the significant augmentation of REM sleep : (2) REM sleep deprivation, prior to learning or immediately thereafter, impairs the formation of a permanent memory/learning : (3) there is a vulnerable period of time(eg, REM sleep "window") following succussful learning, during which REM sleep deprivation results in memory impairment : (4) theta rhythm which develops during REM sleep induces long-term potentiation in hippocampus : (5) there are some evidences providing the relationship of neurotransmitter systems to the maintenance of REM sleep and memory storage processes.

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Improvement of Structure and Electrochemical Properties of LiNi0.5Mn1.5O4 for High Voltage Class Cathode Material by Cr Substitution (Cr 치환을 이용한 고전압용 양극 활물질 LiNi0.5Mn1.5O4의 구조와 전기화학적 성능의 개선)

  • Eom, Won-Sob;Kim, Yool-Koo;Cho, Won-Il;Jang, Ho
    • Journal of the Korean Electrochemical Society
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    • v.8 no.2
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    • pp.82-87
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    • 2005
  • The cathode material, $LiNi_{0.5}Mn_{1.5}O_4$, for high voltage applications of Li-ion batteries exhibits impurity phases due to oxygen deficiency during the high temperature heat treatment. The impurity phase reduces the electrochemical properties of the electrode since the deficiency spinel structure disturbs the lithium ion intercalation and deintercalation. In this study, Cr-substituted $LiNi_{0.5-x}Mn_{1.5}Cr_xO_4(0{\leq}x{\leq}0.05)$ powders are synthesized by a sol-gel method in order to reduce the amount of the impurity phases in the $LiNi_{0.5-x}Mn_{1.5}Cr_xO_4$. Thermal analysis of the cathode material shows that the $LiNi_{0.5}Mn_{1.5}O_4$ without Cr substitution looses $2\%$ of its weight due to oxygen deficiency but the amount of weight loss is diminished when Cr is substituted. XRD analysis also supports the reduction of the impurity phases in the cathode after chromium substitution, suggesting that the improvement of the electrochemical properties such as the capacity retention and electrochemical stability are attributed to the low content of impurity phases in the Cr-substituted $LiNi_{0.5-x}Mn_{1.5}Cr_xO_4.$

Characterization and Culture Optimization of an Glucosidase Inhibitor-producing Bacteria, Gluconobactor oxydans CK-2165 (α-Glucosidase 저해제 생산 균주, Gluconobacter oxydans CK-2165의 특성 및 배양 최적화)

  • Kim, Byoung-Kook;Suh, Min-Jung;Park, Ji-Su;Park, Jang-Woo;Suh, Jung-Woo;Kim, Jin-Yong;Lee, Sun-Young;Choi, Jongkeun;Suh, Joo-Won;Lee, In-Ae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.11
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    • pp.5179-5186
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    • 2012
  • Miglitol, a well-known therapeutic intervention agents for diabetes, exhibits competitive inhibitory activity against ${\alpha}$-glucosidase and it is usually produced through three sequential steps including chemical and bioconversion processes. Gluconobactor oxydans (G. oxydans) belonging to acetic acid bacteria biologically, converts 1-deoxy-1-(2-hydroxyethylamino)-D-glucitol (P1) into a key intermidiate, 6-(2-hydroxyetyl) amino-6-deoxy-${\alpha}$-L-sorbofuranose (P2) by incomplete oxidation. In this study, we identified and optimized fermentation conditions of CK-2165, that was selected in soil samples by comparing the bioconversion yield. CK-2165 strain was found to be closely related to G. oxydans based on the result of phylogenetic analysis using 16S rDNA sequence. Utilization of API 20 kits revealed that this strain could use glucose, mannose, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin and arabinose as carbon sources. The culture conditions were optimized for industrial production and several important factors affecting bioconversion rate were also tested using mycelial cake. Cell harvested at the late-stationary phase showed the highest bioconversion yield and $MgSO_4$ was critically required for the catalytic activity.

Studies on the Bulk Pasteurization System for Composting and Spawn Running of the Cultivated Mushroom, Agaricus bisporus (Lange) Sing (양송이 합성배지(合成培地) 제조(製造) 및 균배양(菌培養)을 위한 Bulk Pasteurization System에 관한 연구(硏究))

  • Shin, Gwan Chull
    • Korean Journal of Agricultural Science
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    • v.9 no.1
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    • pp.269-274
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    • 1982
  • These studies were conducted to evaluate the bulk pasteurization system in comparison with the conventional mushroom growing technique of and to establish the phase II fermentation method for the system. The results obtained were as follows. 1. From the mushroom compost peak-heated in the bulk pasteurization system higher mushroom yield was obtained than that of the conventional method. 2. The compost fermented in the bulk pasteurization system showed poor mycelial growth and low crop. It was caused by the imperfect blower and its operation, not by ununiform moisture content of the compost and ununiform filling. 3. A bulk pasteurization system which modified the mushroom house was not proper for the fermentation of the mushroom compost and the sporophore yields were lower than the standard pasteurization system. 4. In the bulk pasteurization system, peak-heating time, phase II period and quality of the compost were influenced by the air temperature but its effects were not more significant than those of the conventional method. 5. During phase II in the bulk pasteurization system moisture content of the compost at filling did not affect the fermentation of the compost.

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Synthesis and Defect-Structure Analysis of $ThO_2-Tm_2O_3$ Solid Solutions ($ThO_2-Tm_2O_3$ 고용체의 합성 및 결함구조해석)

  • Don Kim;Chang Kwon Kang;Keu Hong Kim;Jae Shi Choi
    • Journal of the Korean Chemical Society
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    • v.31 no.6
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    • pp.491-497
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    • 1987
  • $ThO_2-Tm_2O_3$ (TDT) solid solutions containing 1,3,5,8,10, and 15 mol% $Tm_2O_3$ were synthesized from spectroscopically pure $ThO_2$ and $Tm_2O_3$ polycrystalline powders. The TDT solid solutions were indentified to the fluorite structure by the X-ray powder technique. The values of the lattice parameter were decreased with increasing amount of $Tm_2O_3$ incorporated. But, there was no linearity for the samples containing 8, 10, and 15 mol% $Tm_2O_3$. It was concluded that these samples became incomplete solid solutions. From the intensity analyses of X-ray diffraction patterns, the residual factor was found below 0.13 even for the 15 mol% TDT system. lt was confirmed from the DTA and TGA analyses that any phase transitions did not occur under the experimental condition executed. Comparing the pycnometric density with the lattice parameter obtained from XRD, it was suggested that the predominant defect model be an oxygen vacancy.

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A Study on the Analysis of Polycyclic Aromatic Hydrocarbons in Air (대기중 다환 방향족 탄화수소류의 분석에 관한 연구)

  • Pyo, Hee-Soo;Hong, Jee-Eon;Lee, Kang-Jin;Park, Song-Ja;Lee, Won
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.453-465
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    • 2000
  • Polycyclic aromatic hydrocarbons (PAHs) were produced by thermoreaction (incompletely combustion) of organic compounds such as fuel, gasoline, diesel etc, and were known the strong carcinogenic compounds. In our country, a study for health risk assessment of PAHs in air were needed according to rapidly increasing of motor vehicle and progressing to industrial country. In this study, concentrations of PAHs in 263 air samples of fourteen sites-Seoul, Pusan, etc-according to four times sampling for one year are measured by GC/MSD for basic research for health risk assessment. As the result, 14 PAHs are detected in all samples and annual average concentration of total PAHs was $28.72ng/m^3$ and highest average concentration of total PARs was $47.76ng/m^3$ in winter season. The concentrations of total PAHs are proportioned to amount of extracted organic material (EOM). The average concentration of total PAHs in EOM was 0.28%.

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Molecular Cloning and Analysis of the Genes in the Vicinity of Streptomyces griseus Trypsin (SGT) Gene from Streptomyces griseus ATCC10137 (Streptomyces griseus ATCC10137에서 Trypsin 유전자 sprT의 주변 유전자군 분석)

  • Chi Won-Jae;Kim Mi-Soon;Kim Jong-Hee;Kang Dae-Kyung;Hong Soon-Kwang
    • Korean Journal of Microbiology
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    • v.41 no.4
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    • pp.255-261
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    • 2005
  • A 6.7kb DNA fragment containing the sprT gene encoding Streptomyces griseus trypsin (SGT) was cloned from Streptomyces griseus ATCC 10137, and the complete nucleotide sequence was determined. Nucleotide sequence and deduced amino acid or the EcoRI-HindIII fragment revealed the presence or the six complete ORFs containing the sprT gene and one incomplete ORF, which were named ORF1, SGT, ORF2, ORF3, ORF4, ORF5, and ORF6, respectively. ORF1 has homology with the oxidoreductases from several organisms. ORF2 and ORF3 show similarity with unknown proteins and transcription regulator that belongs to the ArsR family, respectively. ORF4 and ORF5 show homology with the peptidoglycan bound protein with LPXTG motif from Listeria monocytogenes and the membrane protein with transmembrane helix from several organisms, respectively. The last ORF, ORF6, shows homology with the lipoprotein from Streptomyces avermitilis.