http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Preliminary Validation of Robotic Control of Magnetic Particles for Targeted Hyperthermia
Haye Min Ko,Sung Hoon Kim 한국자기학회 2018 Journal of Magnetics Vol.23 No.1
In this paper, we present a new method for targeted hyperthermia using an electromagnetic navigation system. Typically, Fe₃O₄ magnetic nanoparticles (MNPs) are utilized by injection methods. However, the study demonstrated that the proposed method provides active locomotion for targeting a destination within a three-axis Helmholtz coil, and generates heat through a high-frequency heating coil. To realize these two functions, the entire system combined the electromagnetic navigation system and a high-frequency heating system. The Fe₃O₄ MNPs were prepared via chemical synthesis. Using vibrating sample magnetometer (VSM) and X-ray diffraction (XRD), we observed the magnetic properties and structure of the crystals. Through various experimental tests, we investigated the controllability, mobility, and steering ability of the MNPs. In particular, we confirmed the heating characteristics of the fabricated MNPs according to the changes in the magnetic field strength at 205 kHz. On average, the particle cluster generated a temperature of 73.12 °C at 58 kA/m.
Ko, Haye Min,Choi, Hyunbong,Paek, Sanghyun,Kim, Kyungjun,Song, Kihyung,Lee, Jae Kwan,Ko, Jaejung Royal Society of Chemistry 2011 Journal of materials chemistry Vol.21 No.20
<P>The synthesis and characterization of new push-pull chromophores, bisDMFA-diTh-CA, bisDMFA-diTh-MMN, and bisDMFA-diTh-MIMN from 5′-(4-(bis(9,9-dimethyl-9<I>H</I>-fluoren-2-yl)aniline (bisDMFA) electron donating, dithiophene bridging, and various electron withdrawing moieties, cyanoacrylic acid (CA), methylene malononitrile (MMN), and methylene indenylidene malononitrile (MIMN), were demonstrated for efficient solution processed BHJ solar cells. The photophysical properties, the hole mobilities from the space charge limitation of current (SCLC) <I>J</I>-<I>V</I> characteristics, and surface morphologies of these materials/PCBM bulk-heterojunction films were also investigated. The best power conversion efficiency of 3.66% (±0.12) with <I>J</I><SUB>sc</SUB> = 11.82 mA/cm<SUP>2</SUP>, <I>FF</I> = 0.35, and <I>V</I><SUB>oc</SUB> = 0.90 V was observed in the BHJ film fabricated with the bisDMFA-diTh-MMN/C<SUB>71</SUB>-PCBM composite with 3% 1-chloronaphthalene (CN), which is an efficiency ∼82% and ∼49% higher than before and after post-annealing without treatment of CN, respectively.</P> <P>Graphic Abstract</P><P>New push-pull chromophores, bisDMFA-diTh-CA, bisDMFA-diTh-MMN, bisDMFA-diTh-MIMN were synthesized and a power conversion efficiency of 3.66% was observed in the BHJ film fabricated using 3% 1-chloronaphthalene. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1jm10667h'> </P>
Three-Component Reactions of Arynes, Amines, and Nucleophiles via a One-Pot Process
Min, Gyoungwook,Seo, Jeongseob,Ko, Haye Min American Chemical Society 2018 Journal of organic chemistry Vol.83 No.15
<P>An unprecedented three-component reaction of arynes, tertiary amines, and nucleophiles has been demonstrated through ammonium salt intermediates. This protocol allows access to tertiary aniline derivatives containing the piperazine motif in good-to-excellent yields. Expansively, this reaction can produce biologically important 2-(4-phenylpiperazin-1-yl)ethyl-containing molecules using arynes, 1,4-diazabicyclo(2.2.2)octane (DABCO), and nucleophiles via a one-pot process.</P> [FIG OMISSION]</BR>
Seo, Jeong Hoon,Ko, Haye Min Elsevier 2018 Tetrahedron letters: the international organ for t Vol.59 No.7
<P><B>Abstract</B></P> <P>An unexpected reaction between benzynes and isocyanates to generate aromatic amines has been developed under transition-metal-free conditions. The <I>in situ</I> prepared anions formed through cleavage of the NC bond in isocyanates, reacted with aryne precursors to afford various aniline derivatives in moderate to excellent yield and tolerated various substituents on the <I>o</I>-silyl aryl triflate and the isocyanate.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Transition-metal-free and ligand-free reaction. </LI> <LI> Facile approach to construct carbon-nitrogen bond utilizing aryne precursors and isocyanates. </LI> <LI> Unexpected cleavage of NC bond in isocyanates to afford anions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
카테콜-키토산 하이드로겔의 대용량 합성과 자가 치유 특성 분석
최회영 ( Choi Hoe Young ),고혜민 ( Ko Haye Min ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.2
Chemical crosslinking is the most widely used method for hydrogel preparations. We prepared a hydrogel using chitosan catechol/polyvinyl alcohol and sodium tetraborate decahydrate (Na<sub>2</sub>B<sub>4</sub>O<sub>7</sub>·10H<sub>2</sub>O). The formation of hydrogels often presents inconsistent results and issues according to the reaction scale. Therefore, we measured and analyzed the self-healing property and viscoelasticity of hydrogels attributed to scale-up synthesis using a rheometer.
혼합슬래그 잔골재 혼입율에 따른 생체모방 폴리머 혼입 모르타르의 유동성 및 공학적특성
배성호 ( Bae Sung-ho ),박사민 ( Park Sa-min ),김대성 ( Kim Dae-sung ),이재인 ( Lee Jae-in ),고혜민 ( Ko Haye-min ),최세진 ( Choi Se-jin ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.1
In this study, as part of a study to solve the problem of aggregate supply and demand, blast furnace slag fine aggregate and ferronickel slag fine aggregate were used as substitutes for natural fine aggregate, and a bioinspired polymer, a catechol-functionalized chitosan, was used instead of the mixing water.
키토산-카테콜 하이드로겔의 카테콜 함유량에 따른 유변학적 특성 분석
방은지 ( Bang Eun Ji ),고혜민 ( Ko Haye Min ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.2
In this study, two types of chitosan-catechol polymers (a-CP and b-CP) were synthesized and mixed with polyvinyl alcohol (PVA) and sodium tetraborate decahydrate (Na<sub>2</sub>B4O<sub>7</sub>·10H<sub>2</sub>O) to form hydrogels. The characteristics of these polymers were tuned by varying the pH during their syntheses, and their structures were characterized using nuclear magnetic resonance spectroscopy and ultraviolet-visible spectroscopy. Rheological and self-healing properties of hydrogels were evaluated. As a result, the viscoelastic modulus was improved due to the increased functional group content, and the self-healing property was excellent regardless of the functional group content.
생체모방 폴리머의 구조 분석 및 폴리머 혼입율에 따른 시멘트 모르타르의 특성 변화
방은지 ( Bang Eun Ji ),최세진 ( Choi Se-jin ),고혜민 ( Ko Haye-min ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.1
In this study, catechol-functionalized chitosan (Cat-Chit), a well-known bioinspired polymer that imitates the basic structures and functions of living organisms and biological materials in nature, was synthesized and combined with cement mortar in various proportions. The compressive strength, tensile strength, drying shrinkage, accelerated carbonation depth, and chloride-ion penetrability of these mixes were then evaluated. In the ultravioletvisible spectra, a maximum absorption peak appeared at 280 nm, corresponding to catechol conjugation. The sample containing 7.5% Cat-Chit polymer in water (CPW) exhibited the highest compressive strength, and its 28-day compressive strength was ~20.2% higher than that of a control sample with no added polymer. The tensile strength of the samples containing 5% or more CPW was ~2.311.5% higher than that of the control sample. Additionally, all the Cat-Chit polymer mixtures exhibited lower carbonation depths than compared to the control sample. The total charge passing through the samples decreased as the amount of CPW increased. Thus, incorporating this polymer effectively improved the mechanical properties, carbonation resistance, and chloride-ion penetration resistance of cement mortar.
카테콜 작용기를 함유한 키토산 고분자 혼입율에 따른 시멘트 모르타르의 특성 변화
최회영 ( Hoe Young Choi ),최세진 ( Se-jin Choi ),고혜민 ( Haye Min Ko ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.1
We synthesized catechol-conjugated chitosan (CCC) to study its usefulness as a construction material additive in cement mortar. The degree of catechol conju- gation (DOC<sub>cat</sub>) of the synthesized CCC was determined to be approximately 14% by UV-vis and <sup>1</sup>H NMR spectroscopy. Furthermore, the hydroxyl and amine groups in CCC could play a crucial role in hydrogen bonding, metal coordination, and cross-linking processes via interaction with adducts from cement mortar. In this study, we observed an improvement in the compressive strength and absorption rate, suggesting that CCC is a promising candidate for high-performance cement mortar.
Synthesis of catechol‐conjugated chitosan and its application as an additive for cement mortar
Choi Hoe Young,Bae Sung‐Ho,Choi Se‐Jin,Ko Haye Min 대한화학회 2022 Bulletin of the Korean Chemical Society Vol.43 No.1
We synthesized catechol-conjugated chitosan (CCC) to study its usefulness as a construction material additive in cement mortar. The degree of catechol conjugation (DOCcat) of the synthesized CCC was determined to be approximately 14% by UV–vis and 1H NMR spectroscopy. Furthermore, the hydroxyl and amine groups in CCC could play a crucial role in hydrogen bonding, metal coordination, and cross-linking processes via interaction with adducts from cement mortar. In this study, we observed an improvement in the compressive strength and absorption rate, suggesting that CCC is a promising candidate for high-performance cement mortar.