Microfluidic generation of Prussian blue-laden magnetic micro-adsorbents for cesium removal

Kang, Sung-Min,Rethinasabapathy, Muruganantham,Hwang, Seung Kuy,Lee, Go-Woon,Jang, Sung-Chan,Kwak, Cheol Hwan,Choe, Sang-Rak,Huh, Yun Suk Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.341 No.-

<P><B>Abstract</B></P> <P>Here, we designed and synthesized a recoverable multifunctional adsorbent using a microfluidic reaction system and evaluated the removal performance of the smart adsorbent toward radioactive cesium as a model sample. Prussian blue-laden magnetic micro-adsorbents (PB-MNPs-MAs) with uniform morphology and monodispersity were generated via two-step sequential procedures using a glass capillary microfluidic system, followed by chemical co-precipitation with a high production rate. The cesium removal efficacy of the PB-MNPs-MAs was analyzed based on Langmuir and Freundlich isotherms by controlling adsorption parameters such as adsorbent size, initial cesium concentration, and contact time. The adsorption isotherm of the PB-MNPs-MAs was better fitted to the Langmuir model with a maximum cesium adsorption capacity of 58.73 mg g<SUP>−1</SUP>, which was 40% higher than that of macro-adsorbents in a dynamic magnetic field. This result can be attributed to their large specific area, which increased the kinetic rate of cesium adsorption and achieved saturation within 20 min. Additionally, the PB-MNPs-MAs were recovered from wastewater within 5 s under a static magnetic field, indicating their great potential for magnetic actuation. We believe that our PB-MNPs-MAs can encapsulate nano-functional adsorbents and prevent actuation, making them promising for environmental remediation and especially for removal of radionuclides.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PB-MNPs-MAs were generated in microfluidic device using chemical co-precipitation. </LI> <LI> The prepared PB-MNPs-MAs are monodispersed with uniform morphology. </LI> <LI> PB-MNPs-MAs exhibited high Cs adsorption capacity (58.73 mg g<SUP>−1</SUP>). </LI> <LI> 100% recovery of PB-MNPs-MAs is possible under static magnetic field after Cs adsorption. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Antibacterial Effect and Deodorization Effect of Extracts from Different Parts of Zingiber officinale

Young Suk Lee,Young Ju Kang,Min Jeong Ryu 한국피부과학연구원 2020 아시안뷰티화장품학술지 Vol.18 No.4

목적: 생강 부위별 추출물의 피부 상재균에 대한 항균효과 및 암모니아에 대하 소취능을 평가하여 항균소재 및 기능성 향장품 소재 로서의 가능성을 예측하고자 한다. 방법: 피부 상재균에 대한 항균효과는 paper disc 방법으로 측정하였다. 소취효과 측정은 암모 니아 가스 제거 실험을 하였다. 결과: 생강 부위별(잎, 줄기, 뿌리) 추출물 항균효과 측정 결과 S. aureus에 대한 항균효과는 5 mg/ mL 농도에서 각각 3 mm, 3 mm, 2 mm의 clear zone이 확인되었다. S. epidermidis에 대한 항균효과는 각각 8 mm, 5 mm, 4 mm 의 clear zone이 확인되었다. 여드름의 원인균인 P. acnes에서는 각각 4 mm, 3 mm, 1 mm의 clear zone이 확인되었다. P. ovale에 서는 각각 6 mm, 5 mm, 4 mm의 clear zone이 확인되었다. M. furfur에서는 각각 4 mm, 3 mm, 2 mm의 clear zone이 확인되었다. C. albicans에서는 각각 4 mm, 3 mm, 2 mm의 clear zone이 확인되었다. 마지막으로 T. mentagrophytes에 대한 항균효과를 측정 한 결과 5 mg/mL 농도에서 생강 잎 추출물은 6 mm, 줄기 추출물은 4 mm, 뿌리 추출물은 3 mm의 clear zone이 확인되었다. 암모 니아에 대한 소취효과를 측정한 결과 120 min에는 생강 잎 추출물은 98%, 줄기 추출물은 95%, 뿌리 추출물은 91%의 소취효과가 확인되었다. 결론: 생강 부위별 추출물 중 잎 추출물이 7종의 피부상재균에 대한 항균효과도 가장 우수하였으며, 소취효과도 생강 잎 추출물이 가장 높은 효과가 확인되어 항균소재 및 기능성 향장품 소재로서의 가능성을 확인하였다. Purpose: Using extracts from different parts of Zingiber officinale , we aimed to evaluate its antibacterial effect on skin flora and its deodorization effect on ammonia to determine its potential as an antimicrobial ingredient and functional herbal cosmetic ingredient. Methods: The antibacterial effect on skin flora was examined using the paper disc method and the deodorization effect on ammonia was examined by the gas detection method. Results: After evaluating the antibacterial effects of extracts from different parts (leaves, stems, and roots) of Zingiber officinale , antibacterial activity was observed against Staphylococcus aureus (S. aureus ) at a concentration of 5 mg/mL. The leaf, stem, and root extracts had 3 mm, 3 mm, and 2mm clear zones, respectively. For the antibacterial effect against Staphylococcus epidermidis (S. epidermidis ), there were 8 mm, 5 mm, and 4mm clear zones for the leaf, stem, and root extracts, respectively. For Propionibacterium acnes (P. acnes ), a bacterium that causes acne, there were 4 mm, 3 mm, and 1mm clear zones for the leaf, stem, and root extracts, respectively. The results for Pityrosporum ovale (P. ovale ) showed 6 mm, 5 mm, and 4 mm clear zones for the leaf, stem, and root extracts, respectively. For Malassezia furfur (M. furfu ), there were 4 mm, 3 mm, and 2 mm clear zones for the leaf, stem, and root extract, respectively. For Candida albicans (C. albicans ), there were 4 mm, 3 mm, and 2mm clear zones for the leaf, stem, and root extracts, respectively. Finally, after evaluating the antibacterial effect against Trichophyton mentagrophytes (T. mentagrophytes ) at a concentration of 5 mg/mL, we found 6 mm, 4 mm, and 3 mm clear zones for the leaf, stem, and root extracts, respectively. After evaluating the deodorization effects of Zingiber officinale extracts on ammonia, at 120 min, the deodorization effect was 98%, 95%, and 91% for the leaf, stem, and root extracts, respectively. Conclusion: Among the three extracts of Zingiber officinale , the leaf extract had the highest antibacterial effect against the seven types of skin flora as well as the highest deodorization effect, thus confirming its potential as an antibacterial ingredient and functional herbal cosmetic ingredient.

종이접기에 의한 정다각형의 작도

강신민,김석룡 慶尙大學校 1990 論文集 Vol.29 No.1

In classical constuctions the exercise uses a straight edge and a pair of compasses. As in Paper-foldings are not used them, it is impossible to describe a circle or other curves. However, we can receive easily several important geometic processes, to divide straight lines and angles into two or more equal parts to draw perpendiculars and parallels to straight lines. In this paper, I'll make again how to make regular polygons(regular 3-gon, 4-gon, 5-gon, 6-gon, 8-gon, 10-gon, 12-gon) while are confined in some degree by Paper-foldings and make regular 8-gon, 12-gon among them with other method. Finally, I will put the point in making a regular 9-gon which is impossible with a straight edge and a pair of compasses by using any angle into three sections in Paper-foldings and I will explain the course that Paper-foldings maks any angle into three sections which is impossible with only a straight edge and a pair of compasses possible.

우울증 환자에 대한 Amineptine Hydrochloride의 임상 효과

강민희,신석철,왕성근,신윤오 최신의학사 1990 最新醫學 Vol.33 No.7

강소성 가공한 Al에서 Sc과 Zr의 석출 거동

민복기,김형욱,강석봉 대한금속재료학회 2003 대한금속·재료학회지 Vol.41 No.11

The elements of Sc and Zr were added to pure Al for improving thermal stability and refining grain size. Sc was presented on boundaries and Zr dominantly on matrix in as cast state. After homogenization treatment, Sc was dissolved mostly but Zr retained in matrix; though the two elements were presented on the same location in Al-Sc-Zr alloy. Semi-coherent Al₃Sc in Sc added alloy was precipitated during severe plastic deformation, and shown (001)_(matrix)//(001)_(Al₃Sc) orientation relationship with matrix. Al₃Zr in as cast Zr added alloy was shown the orientation relationship (011)_(matrix)//(100)_(Al₃Zr), and partially retained and dissolved with increasing deformation. In the Al-Sc-Zr alloy, retained Al₃Zr had the role of nucleation site for Al-Sc precipitates so that Al₃Zr mainly coexist with Al-Sc precipitates.

Culex pipiens pallens의 난황단백질 합성에 관한 연구

강석희,박영민,조정래,문정희 성균관대학교 기초과학연구소 1987 論文集 Vol.38 No.2

Anautogenous한 모기인 한국산 집모기 Culex pipiens pallens의 난황단백질 합성에 대한 hormone 들의 효과를 조사하였다. 피를 먹지않는 c. pipines 암모기의 head extract를 decapitation한 Aedes atropalpus에게 주사하였을 때 난성숙이 재유발되었으며, 난성숙의 재유발 정도는 우화 후 주사시기가 지연될수록 증가하여 우화 후 24시간에 주사하였을 때 최고에 도달하였다. 피먹은 C. pipiens를 흡혈 즉시 decapitation 또는 abdominal ligation하여도 난성숙이 저지되지 않았다. 이러한 결과는 C. pipiens의 brain hormone은 헙혈 즉시 방축되기 시작하여 난성숙의 시작을 자극하는 것으로 여겨진다. 피를 먹지않은 C. pipiens 암모기에게 β-ecdysone을 주사하거나 또는 head extract 주사 후 JHI을 처리하였을 때 fat body가 합성하는 vitellogenin의 양이 증가하였다. The effect of brain hormone, Juvenile hormone and β-ecdysone on the synthesis of vitellogenin in the anautogenous mosquito, Culex pipiens pallens, has been examined. Head extract from non-blood fed C. pipiens females, when injected into the decapitated Aedes atropalpus females, stimulated egg maturation. The ovarian development in C. pipiens was not completely blocked by decapitation or abdominal ligation performed immediately following a blood feeding. These results suggested that the release of brain hormone in this mosquito may be triggered by a feeding activity. Injection of β-ecdysone or head extract followed by topical application of JH into non-blood fed C. pipiens females stimulated vitellogenin synthesis. These results supported the previous work in Aedes aegypti that brain hormone, JH and ecdysone, in that sequence, are required for the egg maturation.

인공 생명 기법을 이용한 로봇 군 지능 구현

민석기,강훈 중앙대학교 생산공학연구소 1998 생산공학연구소 논문집 Vol.7 No.1

본 논문의 목적은, 인공 생명의 원리에 따라 간단한 지역적 규칙으로부터 복잡한 전역적 지능을 형성하는 복수의 자율 이동 로봇의 창발적 행동을 유도하도록 하는 데 있다. 여기서, 강화 신호를 가진 신경 회로망의 학습 구조를 제안하여 이동 로봇이 집단을 이루어 이동할 때 주변의 정보를 센서로 인지하여 움직이는 방향과 속력이 결정되도록 하였다. 시뮬레이션 결과로써, 동적 환경에서 장애물 및 개체간의 충돌을 방지할 뿐 만 아니라 이동 로봇들이 여러 가지 형태를 유지하며 이동하도록 하는 신경 회로망의 최적 하중값을 실시간으로 구하였다. The objective of this paper is, based upon the principles of artificial life, to induce emergent behaviors of multiple autonomous mobile robots which form from simple local rules to complex global intelligence. Here, we propose an architecture of neural network learning with reinforcement signals which perceives the neighborhood information and decides the direction and the velocity of movement as mobile robots navigates in a group. As results of the simulations, the optimum weights are obtained in real time, which not only prevent from the collisions between agents and obstacles in the dynamic environment, but also have the mobile robots move and keep in various patterns.

Aedes 모기의 단백질 분해효소 활성에 미치는 Brain Factor의 영향

강석희,김민선,문정희 성균관대학교 기초과학연구소 1987 論文集 Vol.38 No.2

본 연구에서는 Aedes aegypti(L.)와 Aedes atropalpus 모기의 난성숙과 중장내 단백질 분해효소 활성에 대한 Brain factor의 영향을 조사하였다. A. aegypti 암모기를 흡혈후 즉시 Decapitation 수술했을 때, midgut trypsin activity는 정상모기의 30%이하 수준으로 절감되었다. 피먹은 암모기를 decapitation 한후 Head extract를 주사하여주면, 난자성숙이 56∼100%의 모기에서 회복되었으며, 중장내 trypsin activity도 60%까지 회복되었다. A. atropalpus 암모기를 성체우화후 즉시 decapitation 하고, 그후 시간에 따라 A. aegypti 혹은 A. atropalpus로부터 추출한 Head extract를 주사한 결과 21시간 내지 24시간에 주사하였을 때 난성숙 및 midgut trypsin activity가 가장 크게 회복되었다. 이러한 결과는 난성숙과정에 있어서 midgut trypsin의 합성 혹은 활성이 Brain factor에 의해 지배, 조절됨을 암시해 준다. Effect of brain factor(s) on the midgut trypsin like enzyme activity in the mosquitoes, Aedes aegypti and Aedes atropalpus, has been examined. In both species of mosquitoes, decapitation, or ligation, between thorax and abdomen, within one hour after a blood feeding in Aedes aegypti, or after adult eclosion in Aedes atropalpus, inhibited the midgut trypsin activity by 70%. The enzyme activity level was not affected by decapitation or ligation when the surgeries were delayed more than 15 hours. Injection of head extracts into decapitated female mosquitoes simulated the midgut trypsin activity by more than 60%. The level of midgut proteolytic activity stimulated by the injection of head extracts gradually increased with the time of injection after the decapitation, showing the maximum response when injected at 24 hours post eclosion. The result seemed to suggest that brain factor may directly stimulate the midgut proteolytic enzyme synthesis.

Tegretol-CR의 抗 躁症 효과에 관한 임상적 연구

강민희,왕성근,신석철 최신의학사 1993 最新醫學 Vol.36 No.7

Al₃Sc 나노 석출물이 ARB 가공한 Al-0.2 wt% Sc 합금의 고경각립계 형성에 미치는 영향

민복기,김형욱,강석봉 대한금속재료학회 2004 대한금속·재료학회지 Vol.42 No.12

The cold rolled Al-0.2 wt% Sc alloy sheets were pre- heat treated: (1) as solution treated at 630℃ for 1 hour and (2) as artificial aged at 300℃ for 5 hours, and the following accumulative roll bonding was conducted up to the 8 cycles at ambient temperature. The interconnecting boundary spacing of the aged alloys was narrow and maintained constantly at each ARB cycle. While, the spacing of solution treated alloy was relatively broad and decreased rapidly with increasing ARB cycles. The fraction of high angle boundaries in both alloys increased gradually with increasing equivalent strain, however the age-ARB alloys showed relatively higher fraction of HAGBs than the solution treat-ARB alloys at the same strain levels. And the former shows faster development of lamellar structure than the later. These variations are attributed to the fact that the nano-scale, semi-coherent A13Sc hinders the migration of dislocation. However, those precipitates cannot apply pinning effect sufficiently during static recrystallization above 350℃ because the driving pressure for recrystallization overcomes the Zener pinning pressure. (Received September 30, 2004)