• The Korean Journal of Physiology and Pharmacology
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• 제2권6호
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• pp.725-732
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• 1998

In order to elucidate the molecular mechanism of the intracellular $Ca^{2+}$ overload frequently reported from diabetic heart, diabetic rats were induced by the administration of streptozotocin, the membrane vesicles of junctional SR (heavy SR, HSR) were isolated from the ventricular myocytes, and SR $Ca^{2+}$ uptake and SR $Ca^{2+}$ release were measured. The activity of SR $Ca^{2+}-ATPase$ was $562{\pm}14$ nmol/min/mg protein in control heart. The activity was decreased to $413{\pm}30$ nmol/min/mg protein in diabetic heart and it was partially recovered to $485{\pm}18$ nmol/min/mg protein in insulin-treated diabetic heart. A similar pattern was observed in SR $^{45}Ca^{2+}$ uptakes; the specific uptake was the highest in control heart and it was the lowest in diabetic heart. In SR $^{45}Ca^{2+}$ release experiment, the highest release, 45% of SR $^{45}Ca^{2+}$, was observed in control heart. The release of diabetic heart was 20% and it was 30% in insulin-treated diabetic heart. Our results showed that the activities of both SR $Ca^{2+}-ATPase$ and SR $Ca^{2+}$ release channel were decreased in diabetic heart. In order to evaluate how these two factors contribute to SR $Ca^{2+}$ storage, the activity of SR $Ca^{2+}-ATPase$ was measured in the uncoupled leaky vesicles. The uncoupling effect which is able to increase the activity of SR $Ca^{2+}-ATPase$ was observed in control heart; however, no significant increments of SR $Ca^{2+}-ATPase$ activities were measured in both diabetic and insulin-treated diabetic rats. These results represent that the $Ca^{2+}$ storage in SR is significantly depressed and, therefore, $Ca^{2+}-sequestering$ activity of SR may be also depressed in diabetic heart.

• 한국재료학회지
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• 제21권6호
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• pp.352-356
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• 2011

[ $Zn_{2(1-x)}Mn_xSiO_4$ ]$0.07{\leq}x{\leq}0.15$) green phosphor was prepared by solid state reaction. The first heating was at $900^{\circ}C-1250^{\circ}C$ in air for 3 hours and the second heating was at $900^{\circ}C$ in $N_2/H_2$(95%/5%) for 2 hours. The size effect of $SiO_2$ in forming $Zn_2SiO_4$ was investigated. The temperature for obtaining single phase $Zn_2SiO_4$ was lowered from $1100^{\circ}C$ to $1000^{\circ}C$ by decreasing the $SiO_2$ particle size from micro size to submicro size. The effect of the activators for the Photoluminescence (PL) intensity of $Zn_2SiO_4:Mn^{2+}$ was also investigated. The PL intensity properties of the phosphors were investigated under vacuum ultraviolet excitation (147 nm). The emission spectrum peak was between 520 nm and 530 nm, which was involved in green emission area. $MnCl_2{\cdot}4H_2O$, the activator source, was more effective in providing high emission intensity than $MnCO_3$. The optimum conditions for the best optical properties of $Zn_2SiO_4:Mn^{2+}$ were at x = 0.11 and $1100^{\circ}C$. In these conditions, the phosphor particle shape was well dispersed spherical and its size was 200 nm.

• Bulletin of the Korean Chemical Society
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• 제6권6호
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• pp.358-361
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• 1985

Thianthrene cation radical perchlorate (1) reacted with azo-bis-2-phenoxy-2-propane (6) to give thianthrene (2), cisthianthrene-5,10-dioxide, 5-(p-hydroxyphenyl) thianthrenium perchlorate (10), acetone, phenol, and 5-(2-propenyl) thianthrenium perchlorate (11) when the mole trtio of 1 to 6 was 1:1. Among the products, 11 was a new compound. However, when the corresponding mole ratio was 5:1, 11 was not formed. Similar result was obtained for azo-bis-2-(p-nitrophenoxy)-2-propane.

• 한방안이비인후피부과학회지
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• 제21권3호
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• pp.69-81
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• 2008

Objective : The purpose of this study was find out the anti-allergic effects of SESHINGO on the allergic rhinitis. Methods : Cell viability was evaluated by the MTT assay. Cells were treated with the indicated concentration of SSG. $TNF-\alpha$ concentration was measured from cell supernatants using ELISA method. IL-4 concentration was measured from cell supernatants using ELISA method.$IFN-\gamma$ concentration was measured from cell supernatants using ELISA method. Total RNA was isolated, $TNF-\alpha$ and IL-4 mRNA expression was detected by RT-PCR analysis Total RNA was isolated, COX-1, COX-2 mRNA was analyzed by RT-PCR analysis. Results : 1. $\beta$-hexosaminidase release in RBL-2H3 cells were decresed by SESHINGO attentively. 2. Secreting ration of $TNF-\alpha$was restrained in RBL-2H3 cells by SESHINGO attentively. 3. Secreting ration of IL-4 was restrained in RBL-2H3 cells by SESHINGO attentively 4. Revelation of $TNF-\alpha$ mRNA was decresed in RBL-2H3 cells as concetration. 5. Revelation of.IL-4 mRNA was decresed in RBL-2H3 cells as concetration. 6. Revelation of COX-2 mRNA was decresed in RBL-2H3 cells. Conclusion : According to above results, to evaluate the effect of SSG on the anti-allergic effects.

• 한국응용곤충학회지
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• 제33권2호
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• pp.60-65
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• 1994

침엽수 계통의 많은 수종은 가해하는 솔잎벌(Nesodiprion japonicus{{{{( { M}_{ ARLATT}) }}}}) 생태중 생활사에 관하여 조사한 것을 요약하면 다음과 같다. 성충은 1년 2회 발생하였으며, 암컷과 수컷이 같은 색 (검정)이고, 암컷의 몸체는 수컷보다 굵고 크며 촉각은 빗살모양으로 수컷이 암컷보다 크다. 성충의 수명은 3~4일, 우화율은 92% 성비는 6(female): 4(male)로 나타났다. 성충은 침엽의 조직내에 1입씩 산란하며 산란된 배 입은 각색으로 변한다. 란 기간은 $14.3\pm$1.2일이었으며, 란의모양은 짧은 바나나형이고 등황색을 띠며 크기는 $2.4\pm$0.2mm 이다. 유충기간은 $30.3\pm$2.1일이고, 크기는 $20.1\pm$2.2mm이다. 두정에는 흑빈이 있고 몸체는 광택이 있는 녹생으로서 전후야란은 황색을 띠고 있다. 노숙유충이 되면 녹색이 연녹색으로 변하고 두정의 흑반도 없어진 후 1회 발생 때의 유충은 솔잎의 기부에 , 2회 대의 유충은 지피물 사이에 고치를 짓고 융화한다. 전용기는 $14.3\pm$2.0일이였고, 크기느 $10.1\pm$0.2mm이다. 용기간은 $12.2\pm$1.3일이었으며, 크기는 $10.1\pm$0.2mm이다.

• 동아시아식생활학회지
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• 제11권4호
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• pp.305-314
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• 2001

The study was conducted to investigate the effect of added green tea and black tea powder on the quality of bread during storage. Tea bread was prepared with 0.1% and 2% concentration of green tea (GT) and black tea(BT) powder. The crude fat contents of GT 2% group and BT 2% group were significantly higher than those of control group. GT l% group and BT l% group. The loaf weight of the control group was the lowest and its loaf volume was the highest. Especially, GT 2% group had the lowest loaf volume. The internal lightness value of control group was the highest. the redness value of BT 2% group and the yellowness value of GT 2% group were the highest. GT 2% group was significantly higher in hardness and gumminess and BT l% group was higher in cohesiveness and springiness. After 5 day storage, the retrogradation of GT 2% group was the highest and that of BT 2% group was the lowest among groups. After 5 day storage. pH. titratable acidity and total colony count of GT 2% group was the lowest and those of control group was the highest. The sensory score of control, GT l% and GT 2% group were evaluated higher than others. The shelf-life of tea breads were prolonged to 1~3 days by adding green tea powder and black tea powder as compared with the control group. but It must be considered the way to increase the quality of bread in loaf volume and retrogradation.

• 한국수소및신에너지학회논문집
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• 제24권2호
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• pp.99-106
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• 2013

The variations of performance and metabolites at an early stage were investigated for the successful start-up technology in continuous fermentative hydrogen production. Unsuccessful start-up was observed when the operation mode was changed from batch to continuous mode after the yield was reached to 0.5 mol $H_2$/mol $hexose_{added}$ by batch mode. $H_2$ production continued till 12 hours accompanied by butyrate production, but did not last with propionate production increase. It was suspected that the failure was due to the regrowth of propionic acid bacteria during batch mode which were inhibited by heat-shock but not completely killed. Thus, successful start-up was tried by early switchover from batch to continuous operation; continuous operation was started after the $H_2$ yield was reached to 0.2 mol $H_2$/mol $hexose_{added}$ by batch mode. Although $H_2$ production rate decreased at an early stage, stable $H_2$ yield of 0.8 mol $H_2$/mol $hexose_{added}$ was achieved after 10 days by lowering down propionate production. And it was also concluded that the reason for $H_2$ production decrease at an early stage was due to alcohol production by self detoxification mechanism against VFAs accumulation.

• 대한화학회지
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• 제20권6호
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• pp.525-532
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• 1976

CO2/KOH catalysis에 의해 2-pyrrolidone과 ${\varepsilon}$-caprolactam의 음이온 중합을 시도하였으며 이 polymer의 물리적 성질을 조사하였다. 2-Pyrrolidone 중합의 경우는, KOH의 농도가 8mole%이상이고 $CO_2/KOH$ mole ratio가 0.45일 때 percent conversion이 가장 높았으며 $50^{\circ}C$가 최적의 온도임을 알았다. ${\varepsilon}$-Carprolactam의 중합에 있어서는 80 ∼ $90^{\circ}C$에서 percent conversion이 낮았고, 150 ∼ $180^{\circ}C$의 온도에서는$ CO_2/KOH$ mole ratio에 크게 관계없이 높은 percent conversion을 얻을 수 있었다. 이들 polymer의 고유점도는 대략 2.0 ∼ 5.0dl/g의 높은 값이었다.

• 한국자동차공학회논문집
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• 제15권3호
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• pp.166-173
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• 2007

A numerical study was conducted to have the effect of $CO_2$ addition to fuel on the chemical reaction mechanism with the change of the initial concentration of $CO_2$ and the axial velocity gradient. From this study, it was found that there were two serious effects of $CO_2$ addition on a non-premixed flame ; a diluent effect by the reactive species reduction and chemical effect of the breakdown of $CO_2$ by the third-body collision and thermal dissociation. Especially, the chemical effect was serious at the lower velocity gradient of the axial flow. It was certain that the mole fraction profile of $CO_2$ was deflected and CO was increased with the initial concentration of $CO_2$. It was also ascertained that the breakdown of $CO_2$ would cause the increasing of CO mole fraction at the reaction region. It was also found that the addition of $CO_2$ did not alter the basic skeleton of $H_2-O_2$ reaction mechanism, but contributed to the formation and destruction of hydrocarbon products such as HCO. The conversion of CO was also suppressed and $CO_2$ played a role of a dilution in the reaction zone at the higher axial velocity gradient.

• 한국세라믹학회지
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• 제32권3호
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• pp.385-393
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• 1995

Akali-resistant porous glass was prepared by phase separation in Na2O-B2O3-SiO2 system containing ZrO2 and MgO. ZrO2 was added for alkali-resistance and MgO for anti-cracking during leaching. Optimal content of ZrO2 for alkali-resistance was 7wt% and devitrification by heat treatment resulted from further addition. Pore size and pore volume were decreased and specific surface area was increased with ZrO2 addition due to depression in phase separation. Addition of 3mol% MgO to mother glass containing 7wt% ZrO2 was effective for anti-crack during leaching. In this case, with phase separation at 55$0^{\circ}C$ and 5$25^{\circ}C$ for 20 hrs. crack-free porous glasses could be prepared. The relation between pore size r and heat treatment time t at 55$0^{\circ}C$ was D=25.58＋18.16t. According to measurement of gas permeability, the mechanism of gas permeation was Knudsen flow. N2 and He permeability of porous glass which was prepared by heat treatment at 55$0^{\circ}C$ for 20 hrs. were 0.843$\times$10-7mol/$m^2$.s.Pa and 2.161$\times$10-7mol/$m^2$.s.Pa respectively.