Corrosion Behavior of Hastelloy C-276 for Carbon-anode-based Oxide Reduction Applications

Jeon, Min Ku,Kim, Sung-Wook,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of Hastelloy C-276 was investigated to identify its applicability for carbon-anode-based oxide reduction (OR), in which Cl₂ and O₂ are simultaneously evolved at the anode. Under a 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar flow, the corrosion rate was less than 1 g·m^-2·h^-1 up to 500℃, whereas the rate increased exponentially from 500 to 700℃. The effects of the Cl₂-O₂ composition on the corrosion rate at flow rates of 30 mL·min^-1 Cl₂, 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂, and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ with a constant 170 mL·min^-1 Ar flow rate at 600℃ was analyzed. Based on the data from an 8 h reaction, the fastest corrosion rate was observed for the 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ case, followed by 30 mL·min^-1 Cl₂ and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂. The effects of the chlorine flow rate on the corrosion rate were negligible within the 5-30 mL·min^-1 range. A surface morphology analysis revealed the formation of vertical scratches in specimens that reacted under the Cl₂-O₂ mixed gas condition.

Corrosion Behavior of Inconel X-750 for Carbon Anode Oxide Reduction Application

Jeon, Min Ku,Kim, Sung-Wook,Lee, Sang-Kwon,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of the Inconel X-750 alloy was investigated for its potential application under a Cl₂-O₂ mixed gas flow in an Ar atmosphere. The corrosion rate was found to be negligible at temperatures up to 400℃ under a flow rate of 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar, whereas an exponential increase was observed in the corrosion rate at temperatures greater than 500℃. The suppression of the corrosion reaction due to the presence of O₂ was verified experimentally at flow rates of 30 mL·min^-1 Cl₂ (4.96 g·m^-2·h^-1), 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ (2.02 g·m^-2 ·h^-1), and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ (1.34 g·m^-2·h^-1) under a constant Ar flow rate of 170 mL·min^-1 at 600℃ for 8 h. The surface morphology analysis results revealed that porous surfaces with tunnel-type holes were produced under the Cl₂-O₂ mixed-gas condition. Furthermore, the effects of the Cl₂ flow rate on the corrosion rate were investigated, indicating that its impact was negligible within the range of 5-30 mL·min^-1 Cl₂ at 600℃.

동맥혈 채혈후 시간 경과 및 온도 변화가 가스분압 및 PH 에 미치는 영향에 관한 연구

김동수,이승환,김건식,강화자,신광일,여민구 대한마취과학회 1989 Korean Journal of Anesthesiology Vol.22 No.6

Blood gas samples are highly susceptible to preanalytic error due to improper methods of obtaining or handling the sample prior to delivery to the laboratory. The errors in the measurement of blood gas analysis are currently derived from the exposure of sample to atmosphere, effects of anticoagulant itself, temperature difference between the measuring electrode and drawn blood and the delay in running the sample. To study the effects of the delay in measuring the sample and the temperature difference between the measuring electrode and drawn blood on values of blood gases and pH, we analyzed the arterial sampling from the 24 patients who were taking elective surgery or on his/her recovery period with indwelling arterial catheter. The plastic sampling syringes were kept at 4。C (refrigerator) or 22。-24。C (room temperature) and analyzed at regular intervals (1, 10, 30, 60,120 min) for 120 minutes. The following results were obtained: 1) When the arterial blood drawn from the anesthetized patients were stored 4。C, partial pressure of oxygen (PaO₂) decreased significantly after 20 min, whereas those stored at room temperature decreased significantly after 10 min. 2) When the arterial blood drawn from the recovery patients were stored at 4。C, PaO₂ did not decrease significantly through the experimental period of 120 min. Although those stored at room temperature did not decrease significantly through the period of 120 min. 3) Partial pressure of carbon dioxide in the arterial blood (PaCO₂,) drawn from the anesthetized patients increased significantly by 120 min. at 4。C, whereas those at room temperature increased significantly after 20 min. 4) PaCO₂, of the recovery patients increased signigicantly by 120 min. at 4。C, whereas those at room temperature increased significantly after 30 min. 5) pH of the arterial blood drawn from either anesthetized or recovery patients decreased significantly by 120 min. at 4。C, whereas those at room temperature decreased significantly after 60 min. 6) No significant changes al oxygen saturation (SaO₂) and content (CaO₂) were noted in either anesthetized or recovery. patients in accordance with time elapsed at 4。C or room temperature. In summary, as the changes of PO₂ in particular higher than physiologic PO₂ and PCO₂ in the arterial blood stored at room temperature are significant in accordance with the delay in measuring, it would be advisable to analyze the sample in a short period of time or to store it in a cool place when the measuring will be delayed.

Effect of Jaeumkanghwatang (JEKHT), a Polyherbal Formula on the Pharmacokinetics Profiles of Tamoxifen in Male SD Rats (1)

Min A Kwak,Soo Jin Park,Sung Hwan Park,Young Joon Lee,Sae Kwang Ku 대한한의학회 2016 대한한의학회지 Vol.37 No.2

Effect of Jaeumkanghwatang (JEKHT), a Polyherbal Formula on the Pharmacokinetics Profiles of Tamoxifen in Male SD Rats (1) - Single Oral Combination Treatment of Tamoxifen 50 mg/kg with JEKHT 100 mg/kg within 5 min -

Kwak, Min A,Park, Soo Jin,Park, Sung Hwan,Lee, Young Joon,Ku, Sae Kwang The Society of Korean Medicine 2016 대한한의학회지 Vol.37 No.2

Objectives: The objective of this study was to elucidate the effect of Jaeumkanghwatang (JEKHT) on the plasma concentration and pharmacokinetics of tamoxifen in combination therapy as a process of the comprehensive and integrative medicine against breast cancer. Methods: After 50 mg/kg of tamoxifen treatment, JEKHT 100 mg/kg was orally administered within 5 min. The plasma were collected at 30 min before administration, 30min, 1, 2, 3, 4, 6, 8 and 24 hrs after end of JEKHT treatment, and plasma concentrations of tamoxifen were analyzed using LC-MS/MS methods. PK parameters of tamoxifen ($T_{max}$, $C_{max}$, AUC, $t_{1/2}$ and $MRT_{inf}$) were analysis as compared with tamoxifen single administered rats. Results: JEKHT did not influenced on the plasma concentrations and pharmacokinetics of tamoxifen after single oral co-administration, within 5min except for some negligible effects on plasma concentration. The $T_{max}$, $C_{max}$, AUC, $t_{1/2}$ and $MRT_{inf}$ of tamoxifen in co-administered rats were quite similar to those of tamoxifen single treated rats. Conclusions: Based on the results of the present study, JEKHT did not influenced on the oral bioavailability of tamoxifen, when they were single co-administered within 5min. However, more detail pharmacokinetic studies should be tested to conclude the possibilities that can be used as comprehensive and integrative therapy with JEKHT and tamoxifen for breast cancers, when they were co-administered, like the effects on the pretreatment of JEKHT and after repeat co-administrations.

자바리, Epinephelus bruneus의 난 발생과 부화에 미치는 수온의 영향

양문호,최영웅,정민민,구학동,오봉세,문태석,이창훈,김경민,한석중,Yang, Moon-Ho,Choi, Young-Ung,Jung, Min-Min,Ku, Hag-Dong,Oh, Bong-Sae,Moon, Tae-Seok,Lee, Chang-Hoon,Kim, Kyong-Min,Han, Seock-Jung 한국발생생물학회 2007 발생과 생식 Vol.11 No.2

This study examined temperature effect in egg development and hatching of longtooth grouper, Epinephelus bruneus. Fertilized embryos was not growth after morula stage at $15^{\circ}C$, at 18, 21, 24 and $27^{\circ}C$, the required time from fertilized embryos to hatching were 70 h. 30 min., 44 h. 10 min., 29 h. 10 min. and 24 h. 30 min., respectively. The hatching rates at $24^{\circ}C$ were higher than the other conditions and the hatching was not occurred at $15^{\circ}C$. These results suggest that the water temperature range of egg development and hatching was $18{\sim}27^{\circ}C$. 이 연구는 실내 사육수조에서 자연산란 후 수정된 난을 대상으로 수온에 따른 난 발생속도와 부화율을 조사하였다. 부화에 이르기까지 각 수온조건에서 소요된 시간은 $15^{\circ}C$에서 상실기 이후 발생이 진행되지 않았고, 18, 21, 24, $27^{\circ}C$에서 각각 70시간 30분, 44시간 10분, 29시간 10분 그리고 24시간 30분이 소요되었다. 부화율은 $15^{\circ}C$에서 0%였고, 18, 21, 24 그리고 $27^{\circ}C$에서 각각 $8.3{\pm}1.2%$, $18.0{\pm}6.2%$, $24.0{\pm}4.0%$ 그리고 $17.0{\pm}7.2%$로 뚜렷한 차이 없이 $24^{\circ}C$에서 다소 높았고 21와 $27^{\circ}C$에서 비슷한 경향이었으며 $18^{\circ}C$에서 가장 낮게 나타났다. 이러한 결과에서 자바리의 난발생 수온범위는 $18{\sim}27^{\circ}C$로 제안된다.

Preliminary Study on Chlorination Reaction of Lithium Carbonate for Carbon-Anode-Based Oxide Reduction Applications

Jeon, Min Ku,Kim, Sung-Wook,Choi, Eun-Young Korean Radioactive Waste Society 2021 방사성폐기물학회지 Vol.19 No.2

The reaction between Li₂CO₃ and Cl₂ was investigated to verify its occurrence during a carbon-anode-based oxide reduction (OR) process. The reaction temperature was identified as a key factor that determines the reaction rate and maximum conversion ratio. It was found that the reaction should be conducted at or above 500℃ to convert more than 90% of the Li₂CO₃ to LiCl. Experiments conducted at various total flow rate (Q) / initial sample weight (W_i) ratios revealed that the reaction rate was controlled by the Cl₂ mass transfer under the experimental conditions adopted in this work. A linear increase in the progress of reaction with an increase in Cl₂ partial pressure (pCl₂) was observed in the pCl₂ region of 2.03-10.1 kPa for a constant Q of 100 mL·min^-1 and W_i of 1.00 g. The results of this study indicate that the reaction between Li₂CO₃ and Cl₂ is fast at 650℃ and the reaction is feasible during the OR process.

Production of Iron-Binding Peptides from Colostral Whey by Enzymatic Hydrolysis

Kim, Sang-Bum,Ku, Min-Jung,Cho, Won-Mo,Ki, Kwang-Seok,Kim, Hyeon-Shup,Nam, Myoung-Soo Korean Society for Food Science of Animal Resource 2010 한국축산식품학회지 Vol.30 No.6

Colostral whey prepared from colostrum (pooled from first six post-partum milkings) was heated for 10 min at $100^{\circ}C$ Heated colostral whey was incubated with 1% enzymes (protein equivalent basis) for 15, 30, 60, 90, and 120 min at $50^{\circ}C$. Papain, pepsin, trypsin, and alcalase produced different degrees of hydrolysis (DH), 10.66%, 12.42%, 10.83%, and 25.31%, respectively, at an incubation time of 120 min. The SDS-PAGE reveals that significant amounts of bovine serum albumin (BSA), ${\beta}$-lactoglobulin (${\beta}$-LG), and ${\alpha}$-lactalbumin (${\alpha}$-LA) survived papain digestion. In contrast, pepsin completely removed BSA but not ${\beta}$-LG present in heated colostral whey. Alcalase completely eliminated BSA, ${\beta}$-LG, and ${\alpha}$-LA. This differential hydrolysis was confirmed by reversed-phase HPLC analysis. Using ion-exchange chromatography, fraction-1 (F-1) was obtained from alcalase hydrolysate at a NaCl gradient concentration of 0.25 M. Reversed-phase HPLC chromatograms of alcalase F-1 showed numerous small peaks, which probably indicate that a variety of new peptides were produced. Iron content of alcalase F-1 was 28.94 ppm, which was the highest among all enzyme fractions, whereas iron content of colostral whey was 36.56 ppm. Main amino acids contained in alcalase F-1 were Thr (15.45%), Glu (14.12%), and Ser (10.39%). Therefore, alcalase can be used to generate good iron-binding peptides in heated colostral whey, and the resulting iron-binding peptides could be suitable as a value-added food ingredient for food supplements.

Effect of Jaeumkanghwatang (JEKHT), a Polyherbal Formula on the Pharmacokinetics Profiles of Tamoxifen in Male SD Rats (2) - Oral Combination Treatment of Tamoxifen 50 mg/kg with JEKHT 100 mg/kg on JEKHT 6-day Repeated Pretreated Rats with 8-day Repeated

Park, Soo Jin,Kwak, Min A,Park, Sung Hwan,Lee, Young Joon,Ku, Sae Kwang Society of Preventive Korean Medicine 2016 대한예방한의학회지 Vol.20 No.2

Objectives : The effects of Jaeumkanghwatang (JEKHT) co-administration on the pharmacokinetics of tamoxifen were observed after oral combination treatment of tamoxifen 50 mg/kg with JEKHT 100 mg/kg on JEKHT 6-day repeated oral pretreated rats with 8-day repeated co-administration to confirm the effects of JEKHT co-administration on the pharmacokinetics of tamoxifen. Methods : Six days after pretreatment of JEKHT 100 mg/kg, tamoxifen 50 mg/kg was co-administered with JEKHT 100 mg/kg, once a day for 8 days within 5 min. The blood were collected at 30 min before administration, 30 min, 1, 2, 3, 4, 6, 8 and 24 hrs after end of first and last 8th tamoxifen treatment, and plasma concentrations of tamoxifen were analyzed using LC-MS/MS methods. PK parameters of tamoxifen ($T_{max}$, $C_{max}$, AUC, $t_{1/2}$ and $MRT_{inf}$) were analysis as compared with tamoxifen single administered. Results : Six-day repeated oral pretreatment of JEKHT and 8-day repeated oral co-administration of tamoxifen within 5 min did not influenced on the plasma concentrations and pharmacokinetic parameters of tamoxifen, oral bioavailability, as compared with tamoxifen single treated rats, except for some negligible effects. Conclusions : It is concluded that JEKHT did not influenced on the plasma concentrations and pharmacokinetic parameters, the oral bioavailability of tamoxifen. Therefore, it is considered that co-administration of JEKHT and tamoxifen will be provide an effective novel treatment regimen on the comprehensive and integrative medicine for breast cancer patients, if they showed favorable synergic effects on the pharmacodynamics or reduce the tamoxifen treatment related toxicity and side effects in future studies.

Energy storage capabilities of nitrogen-enriched pyropolymer nanoparticles fabricated through rapid pyrolysis

Yun, Young Soo,Kim, Yu Hyun,Song, Min Yeong,Kim, Na Rae,Ku, Kyojin,An, Ji Su,Kang, Kisuk,Choi, Hyoung Jin,Jin, Hyoung-Joon Elsevier 2016 Journal of Power Sources Vol.331 No.-

<P><B>Abstract</B></P> <P>Nanostructured pyropolymers contain significant amounts of redox-active heteroatoms, have high specific surface areas, and a defective carbon microstructure, indicating good potential for pseudocapacitive charge storage. In this study, nitrogen-enriched pyropolymer nanoparticles (N-PNs-50) are fabricated from polyaniline nanotubes through rapid pyrolysis at 50 °C min<SUP>−1</SUP>. N-PNs-50 exhibit a nitrogen content of 9.8 wt%, a high specific surface area of 875.8 m<SUP>2</SUP> g<SUP>−1</SUP>, and an amorphous carbon structure with an I<SUB> <I>D</I> </SUB>/I<SUB> <I>G</I> </SUB> intensity ratio of 0.95. These unique characteristics lead to good electrochemical performances, in which reversible capacities of 660 and 255 mAh g<SUP>−1</SUP> are achieved for Li-ion and Na-ion storage, respectively, with favorable voltage characteristics (<1.5 V for Li-ions and <1.2 V for Na-ions). This study provides a more feasible production method for nitrogen-doped pyropolymers and their practicable electrochemical performances for use as an anode in energy storage devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanostructured pyropolymers (N-PNs-50) were fabricated by rapid pyrolysis. </LI> <LI> N-PNs-50 exhibited a nitrogen content of 9.8 wt% and amorphous carbon structure. </LI> <LI> N-PNs-50 exhibited a high specific surface area of 875.8 m<SUP>2</SUP> g<SUP>−1</SUP>. </LI> <LI> 660 and 255 mAh g<SUP>−1</SUP> were achieved for Li-ion and Na-ion storage, respectively. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Nitrogen-enriched pyropolymer nanoparticles (N-PNs-50) were fabricated from polyaniline nanotubes through rapid pyrolysis at 50 °C min<SUP>−1</SUP>, showing superior electrochemical performances.</P> <P>[DISPLAY OMISSION]</P>