Tailoring of nanoporous TiO₂ spheres with 100–200 nm sizes for efficient dye-sensitized solar cells

Yu, Sora,You, Ji Su,Yang, In Seok,Kang, Paul,Rawal, Sher Bahadur,Sung, Sang Do,Lee, Wan In Elsevier 2016 Journal of Power Sources Vol.325 No.-

<P><B>Abstract</B></P> <P>Highly porous and monodispersed TiO<SUB>2</SUB> spheres (SPs) with diameters in the range of 100–200 nm, notably smaller than the conventional SPs reported thus far, were selectively controlled, and found to be an outstanding building block for the mesoporous TiO<SUB>2</SUB> layer in dye-sensitized solar cells (DSCs). The prepared TiO<SUB>2</SUB> films employing these SPs are highly transparent, and the fabricated DSCs exhibit significantly enhanced photovoltaic performances. Particularly, the 100 nm-sized TiO<SUB>2</SUB> SP (SP100) provides a photovoltaic conversion efficiency (PCE) of 10.66% with a <I>J</I> <SUB> <I>SC</I> </SUB> of 17.98 mA/cm<SUP>2</SUP>, <I>V</I> <SUB> <I>OC</I> </SUB> of 808 mV, and <I>FF</I> of 0.734, which is higher than the PCE of DSCs with the typical 20 nm-sized TiO<SUB>2</SUB> nanoparticle (NP20) or conventional 250 nm-sized SP (SP250). Transient photoelectron spectroscopic analyses revealed that both the electron diffusion coefficient and electron lifetime of the TiO<SUB>2</SUB> layer increase as the size of the SPs decreases. The tiny TiO<SUB>2</SUB> SPs prepared in this work offer distinct advantages in electron transport as well as dye-soaking and electrolyte diffusion.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanoporous TiO<SUB>2</SUB> spheres (SPs) with sizes of 100–200 nm are selectively synthesized. </LI> <LI> Prepared SPs are an excellent building block for the mesoporous TiO<SUB>2</SUB> layer of DSCs. </LI> <LI> DSC employing 100 nm-sized TiO<SUB>2</SUB> SP (SP100) demonstrates PCE of 10.66%. </LI> <LI> SP100 shows advantages in electron transport, dye-soaking and electrolyte diffusion. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

High substrate specificity of 3,6-anhydro-<small>L</small>-galactose dehydrogenase indicates its essentiality in the agar catabolism of a marine bacterium

Yu, Sora,Choi, In-Geol,Yun, Eun Ju,Kim, Kyoung Heon Elsevier 2018 Process biochemistry Vol.64 No.-

<P><B>Abstract</B></P> <P>3,6-Anhydro-<SMALL>L</SMALL>-galactose (AHG) is a rare sugar found in red macroalgae. The key metabolic steps in AHG catabolism involve its oxidation into 3,6-anhydrogalactonate (AHGA), followed by cycloisomerization of AHGA into 2-keto-3-deoxy-galactonate. These steps were recently discovered in a marine bacterium <I>Vibrio</I> sp. strain EJY3. In this study, we characterized NAD(P)<SUP>+</SUP>-dependent AHG dehydrogenase (AHGD) involved in the first step of AHG catabolism. AHGD displayed high substrate specificity for AHG, but showed no catalytic activity toward other aldehyde sugars, including D-form of AHG, glucose, and galactose. This high substrate specificity of AHGD may be associated with the unique chemical structure of its substrate AHG. Unlike other common aldehyde sugars, AHG mainly exists in its hydrated form under aqueous conditions. Growth of EJY3 in presence of AHG, agar, and <I>Gelidium amansii</I> but glucose, as the sole carbon source resulted in a significant increase in the AHGD activity of cell-free EJY3 lysates. Amino acid sequence analysis revealed that AHGD is highly homologous to other aldehyde dehydrogenases from agar-degrading bacteria, suggestive of its key role in agar-related metabolism in marine bacteria utilizing red macroalgae. Therefore, AHGD may serve as an important enzyme involved in the bioconversion of red macroalgal biomass to value-added chemicals.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The oxidative activity of AHGD for AHG was confirmed by LC/MS. </LI> <LI> AHGD displayed high substrate specificity toward AHG. </LI> <LI> <I>Vibrio</I> sp. EJY3 under AHG or AHG-containing polymers showed high AHGD activity. </LI> <LI> AHGD is highly homologous to aldehyde dehydrogenases from agar-degrading bacteria. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Biosynthesis of (S)-3-Hydroxybutyrate by Engineered Saccharomyces cerevisiae

Sora YU,Eun Ju YUN,Kyoung Heon KIM 한국생물공학회 2015 한국생물공학회 학술대회 Vol.2015 No.10

만 5세 이야기 나누기 활동에서 나타난 유아교사의 교수화법에 대한 사례연구 : 질문 및 피드백을 중심으로

유소라(Yu, Sora),김민진(Kim, Min-jin) 학습자중심교과교육학회 2020 학습자중심교과교육연구 Vol.20 No.15

본 연구는 만 5세 이야기 나누기 활동에서 나타나는 유아교사의 교수화법을 사례연구방법으로 살펴봄으로써 유아교사의 질문과 피드백이 어떠한 맥락에서 발생되는지 알아보고자 하였다. 유치원 만 5세 한 학급의 담임교사 1명과 24명의 유아들이 참여하였으며, 30회의 이야기 나누기 활동 참여관찰과 2회의 담임교사 면담을 통해 자료를 수집하였다. 연구결과, 주제 관련 질문하기, 주제 관련 개념 설명하기, 다른 유아에게 다시 질문하기, 유아의 응답을 그대로 반복하기, 유아의 응답에 대해 긍정 반응하기, 유아의 응답에 대해 부정 반응하기, 활동에 대한 유아의 느낌과 생각 질문하기로 범주화하였다. 이러한 유아교사의 질문과 피드백은 발생 맥락에 따라 유아의 사고를 지원하거나, 제한함을 살펴볼 수 있었다. 본 연구결과는 각 수업 상황에 적절한 교수화법에 대한 교사교육 지원이 필요함을 시사한다. The aim of this study was to investigate in what context questions and feedback by early childhood teachers occur by adopting a case study method in examining the instructional communication of an early childhood teacher in story sharing activities with 5-year-old children. One homeroom teacher and 24 children from a 5-year-old kindergarten class participated in this study. Data were collected by conducting participatory observation of the story sharing activities and an interview with the teacher. As a result of analyzing the collected data, the teacher’s instructional communication was categorized into asking subject-related questions, explaining subject-related concepts, asking another child again, repeating a child s response verbatim, responding positively to a child s response, responding negatively to a child’s response, and asking questions about a child’s feelings and thoughts about the activity. It was found that these questions and feedback by the early childhood teacher support or limit children’s thinking depending on the context in which they occurred. The findings of this study suggest that it is necessary to support teacher training for instructional communication appropriate to each class situation.

보육교사론 수업에서 나타난 예비보육교사의 보육교사에 대한 인식

유소라(Yu, Sora),박성빈(Park, Sung-bin) 학습자중심교과교육학회 2022 학습자중심교과교육연구 Vol.22 No.9

목적 본 연구에서는 보육교사론 수업에서 나타난 예비보육교사의 보육교사에 대한 인식을 살펴봄으로써 전문성을 갖춘 보육교사가 되도록 지원하는데 기초자료를 마련하고자 하였다. 방법 본 연구의 목적을 위해 15주차 간의 보육교사론 수업에서 학생들이 작성한 저널을 수집하여 예비보육교사의 보육교사에 대한 인식을 범주화하고 해당 사례를 선정하였으며, 연구자의 판단중지와 동료검증을 통해 자료분석의 신뢰도와 타당도를 높이고자 하였다. 결과 본 연구에서 보육교사론을 수강한 예비보육교사들은 보육교사에 대해 개인적⋅사회적 인식의 개선이 필요한 보육교사, 사명감을 가져야 하는 보육교사, 전문성을 갖추어야 하는 보육교사, 부모를 지원하는 보육교사로 인식하는 것으로 나타났다. 결론 본 연구의 결과를 바탕으로 보육교사 양성과정에서 예비보육교사들이 보육교사에 대해 올바른 인식을 형성하고, 전문성 신장을 위한 동기부여가 되도록 적절한 교육이 지원되기를 바란다. Objectives The aim of this study was to provide basic data for supporting childcare teachers with professionalism by examining pre-service childcare teachers’ perceptions of childcare teacher shown in childcare teacher theory classes. Methods To this end, journals written by students in a 15-week childcare teacher theory class were collected. Based on the contents of the journals, pre-service childcare teachers’ perceptions of childcare teacher were categorized, and related cases were selected. Results As a result, this study found that pre-service childcare teachers who took the childcare teacher theory class perceive childcare teachers as those who are in need of improving personal and social awareness, those who must have a sense of duty, those who must have professionalism, and those who support parents. Conclusions Based on the results of this study, it is hoped that appropriate education is applied to childcare teacher training programs so that pre-service childcare teachers form proper perception of childcare teacher and are motivated to develop professionalism.

Neural Induction of Human Mesenchymal Stem Cell Spheroid Using Graphene Oxide and Magnetic Nanoparticles

Sora PARK,Jung In PARK,Yeongju YUN,Jung Won LEE,Yu Na SHIN,Sol A KIM,Sun Min KIM,Tai Hyun PARK 한국생물공학회 2018 한국생물공학회 학술대회 Vol.2018 No.10

Designing a User Interface for Generative Design in Augmented Reality: A Step Towards More Visualization and Feed-Forwarding

Sora Kang,Kaiwen Yu,Xinyi Zhou,Joonhwan Lee 한국HCI학회 2024 한국HCI학회 학술대회 Vol.2024 No.1

Generative design, an AI-assisted technology for optimizing design through algorithmic processes, is propelling advancements across numerous fields. As the use of immersive environments such as Augmented Reality (AR) continues to rise, integrating generative design into such platforms presents a potent opportunity for innovation. However, a vital challenge that impedes this integration is the current absence of an efficient and userfriendly interface for designers to operate within these environments effectively. To bridge this gap, we introduce a novel UI system for generative design software in AR, which automates the process of generating the potential design constraints based on the users inputs. This system allows users to construct a virtual environment, edit objects and constraints, and export the final data in CSV format. The interface enhances the users design experience by enabling more intuitive interactions and providing immediate visual feedback. Deriving from participatory design principles, this research proposes a significant leap forward in the realms of generative design and immersive environments.

RUSLE 공식을 이용한 경사지 농경지의 토양유실 분석

김소래 ( Sorae Kim ),장민원 ( Min-won Jang ),유찬 ( Chan Yu ),최규환 ( Gyu-hwan Choi ),정환봉 ( Hwan-bong Jeong ),장은정 ( Eun-jeong Jang ),이상환 ( Sang-whan Lee ),지원현 ( Won-hyun Ji ) 한국농공학회 2017 한국농공학회 학술대회초록집 Vol.2017 No.-

급경사지 농경지에선 작토층의 토양과 유기물, 영양분 등의 유실이 쉬워 작물 생산성이 저하되고 가뭄 취약성이 높아지는 문제가 발생한다. 강우나 바람 등의 기상작용에 의한 침식발생은 일반적으로 논에 비해 밭에서 현저히 높다. 특히 고랭지 밭은 경사도 및 해발이 높은 곳에 위치하기 때문에 적은 강우에도 토사유출이 심하고 수직경운, 잦은 객토와 연작 등에 따라 토양유실이 많다. 토양유실의 발생은 오염토양복원 현장에서는 더욱 큰 문제를 야기할 수밖에 없다. 현재 광해로 인한 오염 농경지에서 주로 적용되고 있는 복원공법은 크게 오염토양에 대한 환토 혹은 복토공법이다. 특히 복토법은 복원공법에서 차지하는 비중이 큰 데 복토층 토양유실은 하부 오염토층의 지표노출과 오염성분의 누출 위험이 있다. 본 연구는 토양개량복원사업이 진행되고 있는 동아광산지구의 급경사지 농경지를 대상으로 범용토양유실예측공식(RUSLE)을 이용하여 복토사업 전후의 필지별 토양유실평가 및 토양침식위험을 비교·분석하였다. 그 결과 대상지역 전체에 걸친 평균 토양유실량은 사업전 약 127.85 ton/ha/yr, 사업후 약 310.57 ton/ha/yr로 약 2.4배 증가하였고, 토지이용별 평균 토양유실량은(사업전, 사업후) 논(0.13 ton/ha/yr, 0.31 ton/ha/yr), 밭(154.78 ton/ha/yr, 310.57 ton/ha/yr)로 복토사업 후 많은 양의 토양유실이 발생하며, 특히 대부분의 유실이 밭에서 발생하는 것으로 나타났다. 농업과학기술원의 토양침식위험기준에 따라 토양유실등급을 분류한 결과 매우심함(50 ton/ha/yr 이상) 등급으로 분류된 면적이 사업전 17.27 ha, 사업후 24.25 ha로 각각 전체면적의 54.74%, 76.86%의 매우 심각한 수준으로 복토사업 전후 모두 많은 양의 토양유실이 발생하는 것으로 나타났다.

도로 네트워크에서 연속적인 질의 처리를 지원하는 사용자 위치 정보 보호 기법

나소라(Sora Na),유혜겸(Hye-Kyoum Yu),장재우(Jae-Woo Chang) 한국정보과학회 2010 한국정보과학회 학술발표논문집 Vol.37 No.1A

Acupuncture Alleviates Levodopa-Induced Dyskinesia via Melanin-Concentrating Hormone in Pitx3-Deficient aphakia and 6-Hydroxydopamine-Lesioned Mice

Kim, Yu-Kang,Lee, Ah-Reum,Park, Hanseul,Yoo, Junsang,Ahn, Sora,Jeon, Song-Hee,Kim, Jongpil,Park, Hi-Joon Springer-Verlag 2019 Molecular neurobiology Vol.56 No.4