-
- Investigation on the influence of oxygen vacancy location on charge carrier losses in reduced TiO2 nanoparticle
- Theoretically investigated the influence of oxygen vacancy location on the charge carrier losses in reduced titanium dioxide nanoparticles using quantum calculations. Chemistry Prof. LEE, JINYONG Researcher NAM, YEONSIK A joint research team led by Prof. Jin Yong LEE (Dept. of Chemistry) and Prof. Oleg PREZHDO (Univ. of Southern California in USA) theoretically investigated the influence of oxygen vacancy location on the charge carrier losses in reduced titanium dioxide nanoparticles using quantum calculations. This research was published in the Journal of the Physical Chemistry Letters (IF: 8.709, JCR top 6.76 %) as of 8th May, with the title "Strong Influence of Oxygen Vacancy Location on Charge Carrier Losses in Reduced TiO2 Nanoparticles". Titanium dioxide is definitely the most popular resource for the photocatalytic materials on the fields of academia as well as industry. Currently, the photocatalytic activity of TiO2 is limited by the low absorption efficiency of visible light. Oxygen vacancy defect is artificially introduced or natively exist resulting in the enhancement of the visible light absorption. However, the recent studies reported the contradictory experimental results for photocatalytic activity due to the subsequent change of the electron-hole recombination rate by the oxygen vacancy defect. Still, there are many arguments on the influence of oxygen defect for charge carrier recombination and it has not reached any consensus yet. Prof. LEE’s team theoretically investigated the influence of oxygen vacancy location on the electron-hole recombination rate of reduced titanium dioxide nanoparticle based on quantum calculations for the first time. This work will be very useful to help researchers understand the photocatalytic activities of various experiments handling titanium dioxide nanoparticles. Prof. LEE said, "Our theoretical prediction properly explains the contradictory experimental results for photocatalytic activity of reduced titanium dioxide nanoparticles and our results provide guidelines for rational design of nanoscale metal oxides for solar energy harvesting and utilization." This research was supported by the POSCO Science Fellowship of POSCO TJ Park Foundation, National Research Foundation of Korea (NRF), Korea Institute of Science and Technology Information (KISTI) supercomputing center.
-
- 작성일 2019-07-01
- 조회수 2390
-
- AORC Korea-China-US Joint Conference
- SKKU Applied Algebra and Optimization Research Center (hereafter AORC) hosted a joint conference with IRCTMT (China)and IDEaS (US) at Jeju National University from May 23rd to 27th. The topic was “matrix theory and applications: combinatorics, optimization, data analysis”. This conference was in result of the MoU that was established between three institutions. It was first held at Shanghai University last year and this year’s conference is hosted by AORC at Jeju National University. Matrix theory is widely used in the fields of mathematics, natural sciences, engineering, social sciences and data analysis. Scholars from different disciplines were invited and the total number of participants was 121. 6 keynote speeches, 34 lectures and 40 these were presented in the conference. Website: https://shb.skku.edu/aorc/icmta2019/ICMTA2019.jsp
-
- 작성일 2019-06-13
- 조회수 2253
-
- The research article of the Dept. of Biological Science research team has been published
- The research article of the Dept. of Biological Science research team led by Prof. Lee Jae-seong (Department of Biological Science, College of Science, Sungkyunkwan University) has been published in ScienceDirect. The title of this article is 「Effects of ocean acidification on life parameters and antioxidant system in the marine copepod Tigriopus japonicus」 and corresponding authors are Chang-Bum Jeong, Jae-Seong Lee (Department of Biological Science, College of Science, Sungkyunkwan University). You can read the original of the whole article on the ScienceDirect homepage (https://www.sciencedirect.com/science/article/pii/S0166445X19302139). Title : Effects of ocean acidification on life parameters and antioxidant system in the marine copepod Tigriopus japonicus Abstract : Ocean acidification (OA) is caused by alteration of global ocean carbon chemistry due to the increased pCO2 in the atmosphere and caused deleterious impacts on the marine ecosystem. Although various detrimental effects of OA were reported in marine organisms, the potential impact of OA on aquatic invertebrates still remains largely unknown. Here, we examined changes in life parameters and antioxidant system in response to low pH (7.5 and 7) in the marine copepod Tigriopus japonicus. Exposures to lower pHs (pH 7.5 and 7.0) of copepods resulted in lengthening of the developmental time with decreased fecundity and body length. Also, they showed increased reactive oxygen species contents with enhanced glutathione S-transferase and glutathione reductase activities but decreased glutathione peroxidase and superoxide dismutase activities in pH-dependent manner, indicating that OA exposure caused disturbance of the redox system in T. japonicus. Among several oxidative stress-related genes, GSTs2b was significantly up-regulated in response to OA. These findings will be helpful for a better understanding on the potential impact of OA on life parameters and antioxidant system in the marine copepod T. japonicus. Keywords : Low pH seawater; oxidative stress; antioxidant response; marine invertebrate.
-
- 작성일 2019-06-10
- 조회수 2355
-
- Basic Science Institute was selected as the self-operating and focused research institutes
- Basic Science Institute at SKKU was selected as the self-operating and focused research institutes. The education authorities will carry out a project to increase utilization of science and engineering research equipment, which had been scattered throughout each research lab. The Ministry of Education, the National Research Foundation of Korea and the Korea Basic Science Institute announced the results of their selection of 'Project to Strengthen the Research Capabilities of Basic Science' and 'Project to Support University-focused Research Institute' on 30 May. A project to strengthen research capabilities of basic science is to collect research equipment that is not utilized in each field into 'core research support centers' designated for being managed by dedicated personnel. Last year, it operated at three universities on a trial basis and expanded to 20 core research support centers this year. The selected universities will receive 300 million won to 600 million won annually, including costs for operating facilities and equipment for three to six years, as well as labor costs for dedicated personnel (technicians). Also, the Ministry of Education has newly designated 22 university affiliated research institutes as 'University Focused Research Institute' that serve as hubs for academic research in science and engineering. Based on the universityies' mid- and long-term plans to nurture the research institutes and the possibility of developing them into regional hubs, they will carry out research projects with govermental fund between 700 million won and 1.1 billion won annually for six to nine years. This year, the government selected the Seoul National University Institute of Basic Science, Sungkyunkwan University's Institute of Basic Science, Natural Science Institute of KAIST and Jeju National University's Institute of Basic Science as "self-operating and focused research institutes." These research institutes will receive funding for their projects through 'block funding' method where heads of their organizations have autonomy to execute their budgets. This is a translation of the article by Lee Jin-han, MBN. (the original article in Korean: https://www.mk.co.kr/news/society/view/2019/05/362316/)
-
- 작성일 2019-06-03
- 조회수 2041
-
- Analysis for Causes of Fine dust Formation and Development of Technology for Reduction
- Research Areas : Physical Chemistry Researcher : Prof. Kim Young-dok Particulate Matter (PM; fine dust) has recently emerged as a social problem, and discussions on how to solve it are actively taking place in various sectors of society. In order to reduce PM, the government must first scientifically identify how PM is formed, and make efforts to remove the substance responsible for PM based on such scientific verification. Since PM is formed by chemical reactions, efforts are needed to understand the formation of PM from a chemist's point of view and come up with solutions, but unfortunately, chemists' interest in the formation of PM is still not high. Professor Kim Young-dok (Dept. of Chemistry) recently analyzed materials related to the composition and structure of PM in depth which were reported through the media, while examining the process of forming PM in consideration of the contents of the literature published in the field of atmospheric environment and chemistry. And the results were contributed to the Hankyoreh, Financial News, and Engineering Journal in the form of easy-to-understand writings for the general public who did not major in chemistry. With the recent policy of reducing nitrogen oxides emerging as a countermeasure to PM, he explains that it is difficult to reduce PM by simply reducing nitrogen oxides, and that efforts to reduce compounds such as volatile organic compounds and ammonia should be made simultaneously. In addition, Prof. Kim is developing eco-friendly materials that reduce volatile organic compounds, nitrogen oxides, etc., by applying visible light-sensitive photocatalysts developed by his lab to sidewalk blocks, and transfers and commercializes this technology. Prof. Kim also has developed a material that absorbs acetaldehyde, a volatile organic compound, and breaks it down into LED lighting. If the material is installed by the width of the school playground (5000m2), 50g of acetaldehyde can be decomposed per hour. These materials were mass-produced and applied to the technology for manufacturing sidewalk blocks to develop eco-friendly sidewalk blocks. While the existing photocatalysts used in sidewalk blocks only respond to ultraviolet light, his photocatalysts can remove air pollutants not only during daytime but also under lightings at night because of their charateristic responding to visible light. Related articles (Koreans) : 1) http://www.hani.co.kr/arti/opinion/because/890416.html 2) http://www.fnnews.com/news/201904141733309890 3) http://www.engjournal.co.kr/news/articleView.html?idxno=234 4) http://www.lak.co.kr/news/boardview.php?id=6561 5) http://www.fnnews.com/news/201903271730414463 6) https://www.mk.co.kr/news/business/view/2019/03/194293/ 7) http://www.hankookilbo.com/News/Read/201905021677015389 8) http://www.lak.co.kr/news/boardview.php?id=6561
-
- 작성일 2019-05-20
- 조회수 2235
-
- Development of Catalytic Asymmetric Synthetic Method of Cyclobutanones
- Research Areas : Organic Chemistry Researcher : Prof. Ryu Do-hyun, Reasearcher Shim Su-Yong A research team led by Prof. Ryu Do-hyun(Dept. of Chemistry) has developed Lewis acid catalyzed asymmetric synthetic method of cyclobutanones. Chiral four-membered carbocyclic compounds are key structures of bioactive natural products. Therefore, they have attracted a lot of attention in the academic and industrial world. Although four-membered carbocyclic ketone compounds can be obtained from cyclopropane compounds through ring-opening reactions, there has been no example of asymmetric synthesis of cyclobutanones from cyclopropyl aldehydes through rearrangement reactions. The research team developed asymmetric synthetic method of cyclobutanones with chiral Lewis acid catalyst through tandem cyclopropanation/semipinacol rearrangement reaction to give good yields and high enantioselectivities. The newly developed methodology exhibits excellent atom economy because it utilizes simple starting materials and only produces nitrogen gas (N2) as a by-product. Prof. Ryu said, “the synthesis of chiral cyclobutanone compounds through rearrangement of cyclopropyl aldehydes has been an unresolved challenge for the last 50 years. This work is highly valuable because this is the first research result with a catalyst and provides experimental results to elucidate the reaction mechanism.” Cyclobutanones are highly useful compounds because they can be utilized in ring expansion or ring opening reactions due to their innate ring strain. In this regard, this synthetic method is expected to be valuable synthetic tool for further organic synthesis. This research was published in the ‘Journal of the American Chemical Society (JACS; IF : 14.357)’ as of August 8th, 2018, with the title of “Asymmetric Synthesis of Cyclobutanone via Lewis Acid Catalyzed Tandem Cyclopropanation/Semipinacol Rearrangement”. This work was selected as the cover page in recognition of its importance.
-
- 작성일 2019-05-09
- 조회수 2278
-
- SKKU ranked among Top 10 in “THE Asia University Rankings 2019”
- On May 1st, the Times Higher Education announced the “THE Asia University Rankings 2019”. 417 universities from 27 countries were evaluated in this ranking. The first place went to Tsinghua University, second place to National University of Singapore, and the third place went to Hong Kong University of Science and Technology. SKKU received 67.7 points and recorded 10th place in the ranking. SKKU rose 3 places in comparison to last year (2018: 13th place). SKKU has received 60.4 in educational conditions, 64.2 in research performance, 74.8 in thesis citation, 96.9 in research & business profit, 48.8 in internationalization. SKKU earned at least 3 more points for each criteria in comparison to last year. SKKU has set the course of development by making “Student Success” as a new keyword. As part of this, it opened the first Student Success Center in Korea last March. Original Article (Korean): https://www.mk.co.kr/news/society/view/2019/05/282545/
-
- 작성일 2019-05-03
- 조회수 2275
-
- Dedication Ceremony of “Sohyang” Kim Hangja & “Songchun” Ryu Dukhee Lecture room
-
On April 5th, President Dukhee RYU (Kyungdong Pharmaceutical Company) and his family visited SKKU to join the dedication and donation ceremony at the 6th floor of the 600th Anniversary Building. SKKU has dedicated the lecture room in the 6th floor of the 600th Anniversary Building after the pen name of President RYU and his wife. On this day President Ryu also donated 500 mil Won for the school. With this donation, the total amount of donation made by the president accumulated to 10.2 bn Won. Many important figures of SKKU joined the ceremony to express respect and gratitude to President Dukhee RYU. During the ceremony President RYU said, “I was able to make donations thanks to the support of my family. I am very touched and thankful toward the school for giving me this opportunity to payback to my wife who has been a strong supporter. I will continue to support the school in memory of my wife.” Profile of President RYU Dukhee “Songchun” ○ Academics -1956 entered SKKU Dept. of Chemistry (graduated in 61’) -2001 SKKU Honorary Doctorate in Business Administration ○ Career -1960 President of SKKU Student Committee -1960 Representative of SKKU 4.19 Movement Student Task Force -1976~ President of Kyungdong Pharmaceutical Company -1996 Chairman of Catholic Lay Apostolate Council of Korea -2006~2008 The 30th President of SKKU Alumni Association -2010~2016 The 32nd, 33rd, 34th President of SKKU Alumni Association -2010 The 8th Chairman of Korea Pharmaceutical and Bio-Pharma Manufacturers Association ○ Awards -2003 Gold Tower, Order of Industrial Service Merit -2009 “Proud Sungkyun-in” Award -2013 $10 Million Export Award -2014 $20 Million Export Award President RYU Dukhee is an ideal entrepreneur who pioneered through a new area and showed an example of realizing corporate social responsibility. -
- 작성일 2019-04-18
- 조회수 2234
-
- Did Life Begin Within A Water Cage?
- Prof. Choong Eui Song (Department of Chemistry) and his students have recently published a significant article, titled “Hydrophobic chirality amplification in confined water cages” in the world-renowned international journal, Nature Communications. In this study, they provided a plausible scenario for the chiral amplification process, which might help unlock secrets of homochirality on our planet. Homochirality is a fundamental component of molecular recognition in biological systems. Enantiomers (optical isomers) are chiral molecules that are mirror images of one another. They are also non-superimposable to one another. For all intents and purposes, pairs of enantiomers have the same Gibbs free energy. Thus, both enantiomers of a compound will form in equal amounts (a racemic mixture) when we synthesize them in the laboratory under non-chiral environment. However, all living forms on Earth consist of single enantiomer of molecules like D-sugars and L-amino acids, which are basic components for DNA, RNA and proteins (i.e., homochiral). Although homochirality in life forms is found in all living things from wild grasses to human beings, its origin still remains as an unsolved mystery. Most theories for biological homochirality require a chiral amplification mechanism that acts to enhance a small initial asymmetry. Prof. Song’s research team discovered that water can act as a chirality amplifier and thus the enantioselectivity of an asymmetric catalytic reaction can be greatly amplified in the aqueous microdroplets. Flow and batch reactors were evaluated to confirm this general water-induced hydrophobic effects on enantioselectivity. They presumed that this water-enabled chirality amplification stems from the hydrophobic hydration effect, which enforces proximity of the hydrophobic catalyst and substrates in confined water cages and consequently leads to a more compact transition state. Prof. Song says, “This remarkable observation could provide some inspiration for developing new strategies to enhance the enantioselectivity of some catalytic reactions and thus has the potential to open a new chapter in the field of asymmetric catalysis. In addition, considering that the aqueous environment of early Earth resembled aerosol droplets (mist, clouds, and spray, etc.) at the surface of oceans, our results would also offer one of the reasonable scenarios for the chirality amplification process which led to the present homochirality life on our planet. Furthermore, it is likely that the limited diffusion of enantio-enriched products in such droplets might provide a chance to participate in a self-replicating, evolvable system in the prebiotic era.” *Article title: Hydrophobic chirality amplification in confined water cages” Nature Communications, 10, 851 (2019) (DOI: 10.1038/s41467-019-08792-z). Figure 1. Photos of asymmetric catalytic reaction under on-water conditions. a. before reaction; b. during reaction; c. after reaction. Figure 2. Flow microchip reactor Figure 3. (a) Flow microreactor system (b) Plug volume can be controlled by varying the relative flow rates of the two phases (c) Effect of biphasic microfluidic conditions
-
- 작성일 2019-04-08
- 조회수 2254
-
- Prof. Youngdok KIM’s research team develops a fine-dust purifying photocatalytic concrete
- Nature & Environment Inc.’s Research Institute has announced on March 27th that Prof. Youngdok KIM’s research team has successfully developed an “atmosphere purifying concrete block”. Nature & Environment Inc. is currently promoting the installation of concrete blocks with local governments. Prof. KIM’s team developed a way to dissolve the volatile organic compound acetaldehyde into visible light LED. When the new material is installed at a school field track (5000㎡), it dissolves about 50g of acetaldehyde per hour. Volatile organic compound is a carcinogen and is known to be one of sources of fine dust. Original Article (Korean): http://www.fnnews.com/news/201903271730414463
-
- 작성일 2019-04-03
- 조회수 2374