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Scientist of October, Professor Haeshin Lee
(Professor Haeshin Lee from the Department of Chemistry)
Professor Haeshin Lee from the Department of Chemistry received the ‘Science and Technology Award of October’ from the Ministry of Science and ICT and the National Research Foundation of Korea for his contribution to developing an antibleeding injection needle. This novel outcome will fundamentally prevent the problem of secondary infections of AIDS, Ebola and Hepatitis viruses transmitting from patients to medical teams.
This needle’s surface is coated with hemostatic materials. Its concept is simple and the key to this technology is to make materials that are firmly coated on the needle so that they can endure frictional force when being injected into skin and blood vessels. Moreover, the materials should be adhesive to skin and the interior of blood vessels, but harmless to humans.
Professor Lee found a solution from natural polymer ingredients. Catecholamine can be found in mussels. Professor Lee conjugated catechol groups on the chitosan backbone. He applied this mussel-inspired adhesive polymer Chitosan-catechol, which immediately forms an adhesive layer with blood, as a bioadhesion for the antibleeding injection needle.
Professor Lee said, “Chitosan-catechol, which copies the adhesive mechanism of mussels, shows high solubility in physiological saline as well as great mucoadhesion. Hence, it is perfectly suitable for coating the injection needle. Combining it with proteins allows for efficient drug delivery to the heart, which is a challenging injection location, so it will be also useful for treating incurable heart disease.”
2018.10.05 View 10247 -
President Shin Presents Opportunities & Challenges of the 4IR at the Summer Davos Forum
(President Shin makes a keynote speech at the 2018 Summer Davos Forum in China on Sept.20.)
KAIST co-hosted the Asia Session with the World Economic Forum during the 2018 Summer Davos Forum in Tianjin, China from September 18 through 20. The session highlighted regional collaboration in Asia to promote inclusive growth in the Fourth Industrial Revolution.
KAIST is working closely with the WEF to take the lead in the Fourth Industrial Revolution. Last July, KAIST established the Fourth Industrial Revolution Information Center (FIRIC) at the KAIST Institute and signed an MOU with the Center for the Fourth Industrial Revolution (C4IR) at the WEF in October. The session is a follow-up event KAIST and the C4IR agreed to last year during the Roundtable Session held in Seoul.
Many experts in new emerging industries as well as many project directors, including Director Murat Sonmez of the C4IR, attended the session KAIST hosted. Director Chizuru Suga at the C4IR in Japan, Director Danil Kerimi in China, and Director Shailesh Sharda in India also attended the session and discussed ways to expand collaboration and networks among the countries.
In his keynote speech at the session on September 20, President Sung-Chul Shin presented how the Korean government is trying to drive the economy by strategically investing in focused industries in the new global industrial environment. President Shin introduced the government’s strategic roadmap to build the competitiveness of emerging technologies such as AI, blockchain, and precision medicine.
He also stressed that the three components of innovation, collaboration, and speed should be prioritized in all sectors for the successful realization of the Fourth Industrial Revolution. For instance, innovation in education, research, and technology commercialization, expansive domestic and international collaboration beyond the private and public sectors, speedy deregulation, and efficient governance will all be critical.
He also said that KAIST will launch new pilot collaboration projects along with the WEF soon. “We paved the way for leading the network with major countries including Japan and India for advancing the Fourth Industrial Revolution through this session,” President Shin said.
2018.09.21 View 8279 -
Distinguished Professor Sang Yup Lee Announced as the Eni Award Recipient
(Distinguished Professor Sang Yup Lee)
Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering will be awarded the 2018 Eni Advanced Environmental Solutions Prize in recognition of his innovations in the fields of energy and environment. The award ceremony will take place at the Quirinal Palace, the official residence of Italian President Sergio Mattarella, who will also be attending on October 22.
Eni, an Italian multinational energy corporation established the Eni Award in 2008 to promote technological and research innovation of efficient and sustainable energy resources. The Advanced Environmental Solutions Prize is one of the three categories of the Eni Award. The other two categories are Energy Transition and Energy Frontiers. The Award for Advanced Environmental Solutions recognizes a researcher or group of scientists that has achieved internationally significant R&D results in the field of environmental protection and recovery. The Eni Award is referred to as the Nobel Award in the fields of energy and environment.
Professor Lee, a pioneering leader in systems metabolic engineering was honored with the award for his developing engineered bacteria to produce chemical products, fuels, and non-food biomass materials sustainably and with a low environmental impact. He has leveraged the technology to develop microbial bioprocesses for the sustainable and environmentally friendly production of chemicals, fuels, and materials from non-food renewable biomass.
The award committee said that they considered the following elements in assessing Professor Lee’s achievement: the scientific relevance and the research innovation level; the impact on the energy system in terms of sustainability as well as fairer and broader access to energy; and the adequacy between technological and economic aspects.
Professor Lee, who already won two other distinguished prizes such as the George Washington Carver Award and the PV Danckwerts Memorial Lecture Award this year, said, “I am so glad that the international academic community as well as global industry leaders came to recognize our work that our students and research team has made for decades.”
Dr. Lee’s lab has been producing a lot of chemicals in environmentally friendly ways. Among them, many were biologically produced for the first time and some of these processes have been already commercialized. “We will continue to strive for research outcomes with two objectives: First, to develop bio-based processes suitable for sustainable chemical industry. The other is to contribute to the human healthcare system through development of platform technologies integrating medicine and nutrition,” he added.
2018.09.12 View 7706 -
Center for Industrial Future Strategy Takes Off at KAIST
(Professor Wonjoon Kim from the School of Business and Technology Management)
Professors from KAIST and major international universities launched a mega-scale research center focusing on the Fourth Industrial Revolution, named the Center for Industrial Future Strategy (CIFS).
This center is funded by the National Research Foundation Korea and will receive 2.25 billion KRW over four years.
Directed by Professor Wonjoon Kim from the School of Business and Technology Management, the center is comprised of ten top-tier researchers and four research associates, including Professor Hawoon Jeong (KAIST), Professor Scott Stern (MIT), Professor Aaron Chatterji (Duke University), Dr. Yong Suk Lee (Stanford University) and Professor Hyejin Youn (Northwestern University).
The center will conduct research on technical, social, and economic changes derived by a new paradigm of technological innovation.
Moreover, they will study policies and strategies in relation to innovation in the corporate and government sectors to achieve economic growth in a sustainable manner. The center will also propose policies and strategies in a variety of economic and industrial settings to establish a sustainable and global innovation ecosystem.
To carry out these studies successfully, CIFS will further expand the AIEA-NBER Conference with the Asia Innovation and Entrepreneurship Association (AIEA) and the National Bureau of Economic Research (NBER) in which numerous Nobel Laureates in Economics are affiliated. They will also comprise thematic research teams with co-founding universities to build stronger cooperation with one another.
Besides the academic cooperation, the center will also build partnerships with international organizations, including the Asian Development Bank and the Inter-American Development Bank to carry out their missions at multilateral levels.
Their research topics include changes to value chains in a new paradigm of technological innovation, labor market changes in the Fourth Industrial Revolution, sharing economies and social interests, big data, artificial intelligence & privacy policy, and innovation & ethical and institutional countermeasures to AI technology.
Professor Kim said, “The new paradigm of technological innovation is evolving social, economic, and industrial structures, such as R&D, industry, technology, labor, finance, and institutions. The Center will contribute to proposing policies and strategies so that Korea, as well as the international community, can take appropriate measures to these big changes.”
2018.09.11 View 10574 -
NEREC Summer Program Keeps Fellows Thinking, Engaged in Nuclear Nonproliferation
Nuclear technology is more than just technology. It is the fruit of the most advanced science and technology. It also requires high standards of policymaking and global cooperation for benefiting the technology.
As part of the fifth annual Nuclear Nonproliferation Education and Research Center (NEREC) Summer Fellows Program at KAIST, 24 students from 15 countries participated in six-week intensive education and training program. NEREC is the only university-based center dedicated to nuclear nonproliferation education and research established in 2014.
The program, which provides multidisciplinary lectures and seminars on nuclear technology and policy as well as international relations, was designed to nurture global nuclear technology experts well equipped in three areas: in-depth knowledge of technology, applicability gained from sound policy building, and negotiating for international cooperation. It now has grown into the most popular summer program at KAIST.
During the program from July 6 to August 18, participants were able to engage in enriching and stimulating learning experiences in tandem with policies and technology for the utilization and provision of peaceful and safe nuclear technology.
Participating fellows also had to conduct a group research project on a given topic. This year, they explored nuclear nonproliferation issues in relation to nuclear exports and brainstormed some recommendations for current policy. They presented their outcomes at the 2018 NEREC Conference on Nuclear Nonproliferation. After intensive lecture sessions and group research work, the fellows went off to key policy think-tanks, nuclear research institutes, and research power facilities in Korea, Japan, and China.
“NEREC emphasizes nuclear nonproliferation issues related to civilian nuclear power and the associated nuclear fuel cycle development from the point of technology users. I am very glad that the number of participants are increasing year by year,” said the Director of NEREC Man-Sung Yim, a professor in the Department of Nuclear and Quantum Engineering.
Participants’ majors vary from nuclear engineering to international relations to economics. The fellows divided into two groups of graduate and undergraduate courses. They expressed their deep satisfactory in the multidisciplinary lectures by scholars from KAIST, Seoul National University, and Korea National Defense University.
Many participants reported that they learned a lot, not only about policy and international relations but on the research they are conducting and what the key issues will be in dealing for producing meaningful research work.
Moad Aldbissi from the KTH Royal Institute of Technology is one of the students who shared the same view. He said, “Coming from a technical background in nuclear engineering, I managed to learn a lot about nuclear policy and international relations. The importance of integrating the technical and political fields became even clearer.”
Most students concurred that they recognized how important it was to make international collaboration in this powerful field for each country through this program.
“As an engineering student, I just approached this program like an empty glass in policy areas. While working with colleagues during the program, I came to understand how important it is to make cooperation in these fields for the better result of national development and international relations,” said Thanataon Pornphatdetaudom from the Tokyo Institute of Technology.
To Director Yim, this program is becoming well positioned to educate nuclear policy experts in a number of countries of strategic importance. He believes the continuous supply of these experts will contribute to promoting global nuclear nonproliferation and the peaceful use of nuclear energy while the use of nuclear technology continues.
2018.09.04 View 10729 -
Improved Efficiency of CQD Solar Cells Using an Organic Thin Film
(from left: Professor Jung-Yong Lee and Dr. Se-Woong Baek)
Recently, the power conversion efficiency (PCE) of colloidal quantum dot (CQD)-based solar cells has been enhanced, paving the way for their commercialization in various fields; nevertheless, they are still a long way from being commercialized due to their efficiency not matching their stability. In this research, a KAIST team achieved highly stable and efficient CQD-based solar cells by using an amorphous organic layer to block oxygen and water permeation.
CQD-based solar cells are light-weight, flexible, and they boost light harvesting by absorbing near-infrared lights. Especially, they draw special attention for their optical properties controlled efficiently by changing the quantum dot sizes. However, they are still incompatible with existing solar cells in terms of efficiency, stability, and cost. Therefore, there is great demand for a novel technology that can simultaneously improve both PCE and stability while using an inexpensive electrode material.
Responding to this demand, Professor Jung-Yong Lee from the Graduate School of Energy, Environment, Water and Sustainability and his team introduced a technology to improve the efficiency and stability of CQD-based solar cells.
The team found that an amorphous organic thin film has a strong resistance to oxygen and water. Using these properties, they employed this doped organic layer as a top-hole selective layer (HSL) for the PbS CQD solar cells, and confirmed that the hydro/oxo-phobic properties of the layer efficiently protected the PbS layer. According to the molecular dynamics simulations, the layer significantly postponed the oxygen and water permeation into the PbS layer. Moreover, the efficient injection of the holes in the layer reduced interfacial resistance and improved performance.
With this technology, the team finally developed CQD-based solar cells with excellent stability. The PCE of their device stood at 11.7% and maintained over 90% of its initial performance when stored for one year under ambient conditions.
Professor Lee said, “This technology can be also applied to QD LEDs and Perovskite devices. I hope this technology can hasten the commercialization of CQD-based solar cells.”
This research, led by Dr. Se-Woong Baek and a Ph.D. student, Sang-Hoon Lee, was published in Energy & Environmental Science on May 10.
Figure 1. The schematic of the equilibrated structure of the amorphous organic film
Figure 2. Schematic illustration of CQD-based solar cells and graphs showing their performance
2018.08.27 View 8182 -
'K-FLEX' Makes a Splash as a Flexible Endoscopic Surgical Robot
( Robot arms perform an incision during an ex-vivo test on a porcine gallbladder.)
K-FLEX, a flexible endoscopic surgical robot developed by the KAIST Future Medical Robotics Research Center, opens a new chapter for minimally invasive robot-assisted surgery with its precision control of 3.7 mm diameter robotic arms. The two arms, placing at the end of flexible endoscopes, highlight impeccable precision control and robust mini-joint design technologies. While cruising through the complicated inner body pliably, it carries out procedures on the spot with its robotic arms.
The research team under Professor Dong-Soo Kwon recently tested the device in-vivo, conducting a complicated endoscopic procedure dissecting a porcine gallbladder in collaboration with Professor Dae-Kyung Son of the National Cancer Center. The arms successfully manipulated the tissue safely.
During the test, K-FLEX, inserted through an incision in the navel, snaked through the narrow passages of the complicated inner organs. When reaching the desired spot, one of the robot arms pushed aside and held up the nearby tissue to secure proper vision and space for the procedure. Meanwhile, a cautery needle mounted at the tip of the other hand removed the lesion tissue on the gallbladder. The tiny camera installed at the front of the robot arms relayed the internal conditions. The full procedure was able to be monitored from the master console.
The two arms are placed onto 4.2 mm internal channels of an endoscope which is 17 mm in diameter. The arms can be deployable forward and backward and are extendable up to 7 cm for performing procedures.
K-FLEX is made of domestically produced components, except for the endoscopic module. It will expand new medical robotics research while offering novel therapeutic capabilities for endoscopes.
Flexible endoscopes are very promising for surgical applications because they can treat areas thought to be difficult to reach, such as the posterior side of an organ. Current rigid-type laparoscopic tools could not reach a lesion if it occurs in such serpentine and complicated areas. However, this flexible endoscopic surgery robot will bypass obstacles to reach the troubled area.
The ability to seamlessly integrate effective actuation into millimeter-scale deployable mechanisms fits well with minimally invasive surgical procedures. This flexible endoscopic surgery robot, only half the size of current laparoscopic surgical robots, is deployable into natural orifices such as the mouth, anus, and vagina without requiring external incisions. Laparoscopic devices and robots require at least three to four external incisions to insert the devices; however, the applicability of internal incisions reduces the possibility of complications arousing from excessive bleeding and bacterial infections.
Despite these advantages, it has remained challenging to manipulate the robotic arms of flexible endoscopes with integrated grabbing force, flexibility, and multiple degrees of freedom for clinical environments.
The team focused on smaller but smarter devices. Dr. Min-Ho Hwang, a principal researcher of K-FLEX, said that developing tiny robots that are able to generate the necessary forces without compromising safety was the challenge. They created a robust but smaller-joint technology that can exert a relatively greater force even into millimeter scale.
Professor Kwon said, “K-FLEX is the first flexible endoscopic surgery robot in Korea. We already confirmed the clinical adaptation through ex vivo tests and will see complete commercialization in two to three years.” The team believes K-FLEX will be very effective for surgery on incipient cancer cells in the stomach, colon, and thyroid.
Professor Kwon and his eight researchers recently established a tech start-up called EasyEndo Surgical Inc. with these core technologies. In June, K-FLEX won the ‘Best Application Award’ and the ‘Overall Winner’ at the Surgical Robot Challenge 2018 held at Imperial College London. The Korea Research Foundation funded the research on K-FLEX.
(The team conducts a procedure using K-FLEX, flexible endoscopic surgical robot.)
2018.08.17 View 8806 -
Participation in the 2018 Bio-Digital City Workshop in Paris
(A student make a presentatiion during the Bio-Digital City Workshop in Paris last month.)
KAIST students explored ideas for developing future cities during the 2018 Bio-Digital City Workshop held in Paris last month.
This international workshop hosted by Cité des Sciences et de l'Industrie was held under the theme “Biomimicry, Digital City and Big Data.” During the workshop from July 10 to July 20, students teamed up with French counterparts to develop innovative urban design ideas. Cité des Sciences et de l'Industrie is the largest science museum in Europe and is operated by Universcience, a specialized institute of science and technology in France.
Professor Seongju Chang from the Department of Civil and Environmental Engineering and Professor Jihyun Lee of the Graduate School of Culture Technology Students led the students group.
Participants presented their ideas and findings on new urban solutions that combine biomimetic systems and digital technology. Each student group analyzed a special natural ecosystem such as sand dunes, jellyfish communities, or mangrove forests and conducted research to extract algorithms for constructing sustainable urban building complexes based on the results. The extracted algorithm was used to conceive a sustainable building complex forming a part of the urban environment by applying it to the actual Parisian city segment given as the virtual site for the workshop.
Students from diverse background in both countries participated in this convergence workshop. KAIST students included Ph.D. candidate Hyung Min Cho, undergraduates Min-Woo Jeong, Seung-Hwan Cha, and Sang-Jun Park from the Department of Civil and Environmental Engineering, undergraduate Kyeong-Keun Seo from the Department of Materials Science and Engineering, JiWhan Jeong (Master’s course) from the Department of Industrial and Systems Engineering, Ph.D. candidate Bo-Yoon Zang from the Graduate School of Culture Technology. They teamed up with French students from diverse backgrounds, including Design/Science, Visual Design, Geography, Computer Science and Humanities and Social Science.
This workshop will serve as another opportunity to expand academic and human exchange efforts in the domain of smart and sustainable cities with Europe in the future as the first international cooperation activity of KAIST and the Paris La Villette Science Museum.
Professor Seong-Ju Chang who led the research group said, "We will continue to establish a cooperative relationship between KAIST and the European scientific community. This workshop is a good opportunity to demonstrate the competence of KAIST students and their scientific and technological excellence on the international stage.”
2018.08.01 View 10922 -
Visualizing Chemical Reaction on Bimetal Surfaces
Catalysts are the result of many chemists searching to unravel the beauty of molecules and the mystery of chemical reactions. Professor Jeong Young Park from the Department of Chemistry, whose research focuses on catalytic chemical reactions, is no exception. His research team recently made breakthroughs in addressing long-standing questions for understanding reaction mechanisms on bimetal catalysts.
During the studies reported in Science Advances, following a publication in Nature Communications this month, Professor Park’s research team identified that the formation of metal–oxide interfaces is the key factor responsible for the synergistic catalytic effect in bimetal catalysts. The team confirmed this fundamental reaction mechanism through in situ imaging of reaction conditions. This is the first visualization of bimetal surfaces under reaction conditions, signifying the role of metal–oxide interfaces in heterogeneous catalysis.
Bimetallic materials have outstanding catalytic performance, which opens a new pathway for controlling electronic structures and binding energy in catalysts. Despite considerable research on various catalytic reaction efficiencies, there are yet unanswered questions on the underlying principles behind the improved performance. Even more, it was very hard to figure out what led to the efficiency because the structure, chemical composition, and oxidation state of bimetallic materials change according to reaction conditions.
Recently, some research groups suggested that oxide–metal interfacial sites formed by the surface segregation of bimetallic nanoparticles might be responsible for the increased catalytic performance. However, they failed to present any definitive evidence illustrating the physical nature or the fundamental role of the oxide–metal interfaces leading to the improved performance.
To specifically address this challenge, the research team carried out in situ observations of structural modulation on platinum–nickel bimetal catalysts under carbon monoxide oxidation conditions with ambient pressure scanning tunneling microscopy and ambient pressure X-ray photoelectron spectroscopy.
The team observed that platinum–nickel bimetal catalysts exhibited a variety of different structures depending on the gas conditions. Under ultrahigh vacuum conditions, the surface exhibited a platinum skin layer on the platinum–nickel alloyed surface, selective nickel segregation followed by the formation of nickel oxide clusters using oxygen gas, and finally the coexistence of nickel oxide clusters on the platinum skin during carbon monoxide oxidation. The research team found that the formation of interfacial platinum–nickel oxide nanostructures is responsible for a highly efficient step in the carbon monoxide oxidation reaction.
These findings illustrate that the enhancement of the catalytic activity on the bimetallic catalyst surface originates from the thermodynamically efficient reaction pathways at the metal–metal oxide interface, which demonstrates a straightforward process for the strong metal–support interaction effect. The formation of these interfacial metal–metal oxide nanostructures increases catalytic activity while providing a thermodynamically efficient reaction pathway by lowering the heat of the reactions on the surface. [J. Kim et al. Adsorbate-driven reactive interfacial Pt-NiO1-x nanostructure formation on the Pt3Ni(111) alloy surface, Science Advances (DOI: 10.1126/sciadv.aat3151 ]
Professor Park said that one way to monitor catalysts is to detect hot electrons associated with energy dissipation and conversion processes during surface reactions. His team led the real-time detection of hot electrons generated on bimetallic PtCo nanoparticles during exothermic hydrogen oxidation. The team successfully clarified the origin of the synergistic catalytic activity of PtCo nanoparticles with corresponding chemicurrent values.
By estimating the chemicurrent yield, the research team conclude that the catalytic properties of the bimetallic nanoparticles are strongly governed by the oxide–metal interface, which facilitates hot electron transfer. [H. Lee et al. Boosting hot electron flux and catalytic activity at metal–oxide interfaces of PtCo bimetallic nanoparticles, Nature Comm, 9, 2235 (2018)].
Professor Park explained, “We feel that the precise measurement of hot electrons on catalysts gives insight into the mechanism for heterogeneous catalysis, which can help with the smart design of highly reactive materials. The control of catalytic activity via electronic engineering of catalysts is a promising prospect that may open the door to the new field of combining catalysis with electronics, called “catalytronics.” He added that the study also establishes a strategy for improving catalytic activity for catalytic reactions in industrial chemical reactors.
Professors Park and Yousung Jung from the Department of Chemical and Biomolecular Engineering and the Graduate School of EEWS conducted this research in collaboration with Professor Bongjin Mun from the Department of Physics at GIST.
Figure 1. Evolution of surface structures of PtNi bimetal surfaces under various ambient conditions.
Figure 2. Formation of Pt-CoO interface leads to the catalytic enhancement of PtCo bimetal catalysts.
2018.07.25 View 9975 -
Distinguished Professor Lee Receives 2018 George Washington Carver Award
(Distinguished Professor Lee)
Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering will become the 11th recipient of the George Washington Carver Award. The award ceremony will be held during the 2018 Biotechnology Innovation Organization (BIO) World Congress on Industrial Biotechnology from July 16 through 19 at the Pennsylvania Convention Center in Philadelphia.
The annual Carver award recognizes an individual who has made a significant contribution to building the bio-based economy by applying industrial biotechnology to create environmentally sustainable products. It serves as a lasting memorial to the original vision of George Washington Carver who, over a century ago, pioneered bio-based products, materials, and energy derived from renewable agricultural feedstock. Previous recipients include the founder and CEO of POET Jeff Broin, the CEO of DuPont Ellen Kullman, and Professor Gregory Stephanopoulos at MIT.
Professor Lee is a pioneering scholar of systems metabolic engineering, leveraging technology to develop microbial bioprocesses for the sustainable and environment-friendly production of chemicals, fuels, and materials from non-food renewable biomass. He also serves as the dean of the multi-and interdisciplinary research center hub, KAIST Institute.Through his work, Professor Lee has garnered countless achievements, including being one of only 13 people in the world elected as a foreign member of both the National Academy of Sciences USA and the National Academy of Engineering USA.
He has actively promoted the importance of industrial biotechnology through engagement with the public, policymakers, and decision makers around the world. He currently serves as the co-chairman of the Global Future Council on Biotechnology for the World Economic Forum and served as the Chairman of the Emerging Technologies Council and Biotechnology Council for the World Economic Forum.
Upon the award announcement, Dr. Brent Erickson, executive vice president of BIO’s Industrial & Environmental Section lauded Professor Lee’s achievement, saying “Dr. Lee has advanced the bio-based economy by developing innovative products and processes that are sustainable and environmentally friendly. In doing so, he has become a leader in advocating on the importance of industrial biotechnology. His contributions to the advancement of the industry are a continuation of the legacy left behind by George Washington Carver.”
Professor Lee thanked his research team who has worked together for the past few decades, adding, “Industrial biotechnology is becoming increasingly important to help achieve the UN’s Sustainable Development Goals. We should continue to work together to advance the field and establish a solid foundation for the sustainable future.”
The George Washington Carver Award is sponsored by the Iowa Biotechnology Association. Joe Hrdlicka, executive director of the Iowa Biotechnology Association, said, “Dr. Sang Yup Lee’s significant contributions to the advancement of industrial biotechnology make him the perfect recipient for the George Washington Carver Award. Having published more than 575 peer-reviewed papers, contributed to 82 books, and holding 636 patents, the culmination of Dr. Lee’s work has led to the establishment of sustainable systems for bio-based production of chemicals, fuels, and materials, thus reducing environmental impact and improving quality of life for all.”
2018.07.12 View 11754 -
Photonic Capsules for Injectable Laser Resonators
A KAIST research group presented photonic capsules for injectable laser resonators using microfluidic technology. The capsule’s diameter is comparable to a human hair and stable in gas and liquid media, so it is injectable into any target volume.
The research group headed by Professor Shin-Hyun Kim in the Department of Chemical and Biomolecular Engineering applied an interesting optical property from nature. Professor Kim, who has dived deep into photonic materials research inspired from nature such as the Morpho butterfly, used a trait of beetles this time.
Chrysina gloriosa, commonly known as the glorious beetle, shows a green color similar to leaves when illuminated by left-handed, circularly-polarized light while showing no color with right-handed, circularly-polarized light. This unique optical feature helps the beetles communicate with each other and protects them from predators.
The principle behind this interesting optical property of the beetles relies on helical nanostructures with left-handedness that are present on the shell of the beetles. The helical structures reflect a circularly-polarized light with the same handedness of the helix at the wavelength selected by the helical pitch through optical interference.
Such helical nanostructures can be artificially created using liquid crystals (LCs). LCs with a helical arrangement are referred to as cholesteric LCs (CLCs). The CLCs exhibit the polarization-dependent reflection of light in the same manner as the beetles and have been used for various photonic applications.
In particular, CLCs have been cast to a film format that serves as mirrorless laser resonators, unlike conventional lasing systems. However, the film-type CLCs are large in size and show unidirectional emission, which restricts the use of CLC resonators in microenvironments.
To overcome these limitations, Professor Kim’s group has encapsulated the CLCs with dual shells using microfluidic technology. The inner shell is a water layer that promotes the alignment of LC molecules and the outer shell is an elastic polymer layer that secures capsule stability and enables reversible mechanical deformation. The spherical symmetry of the capsules enables omnidirectional laser emissions. Moreover, laser intensity and lasing direction can be further controlled by deforming the capsules, while its wavelength remains tunable. This new type of CLC laser resonator is promising for laser treatments in various biomedical applications.
Professor Kim said, “The helical nanostructure used in the laser resonator resembles that of the shell of chrysina gloriosa. Humans learn from nature and engineer materials to create something unprecedented.”
This research was led by graduate student Sang Seok Lee and an article entitled “Wavelength-tunable and shape-reconfigurable photonic capsule resonators containing cholesteric liquid crystals” was published online on June 22, in Science Advances.
Figure 1. Chrysina gloriosa illuminated by left-handed (left panel) and right-handed (right panel) circularly-polarized lights.
(Image source: https://doi.org/10.1016/j.cub.2010.05.036 , permitted for reuse in news media)
Figure 2. Composition (left panel) and optical microscopy image (right panel) of the capsule-type laser resonator
2018.07.05 View 9427 -
ICT Volunteer Corps Off to Africa
A volunteer corps made up of students will take part in ICT education services in Ethiopia, Tanzania, and Uganda. KAIST students have been volunteering with the ICT education program in Africa since 2015.
The volunteer corps will be made up of 51 students from 13 teams and will be conducting services for a month through the end of July at Addis Ababa Institute of Technology (AAiT) in Ethiopia, Nelson Mandela African Institute of Science and Technology (NM-AIST) and Star High School in Tanzania, and IT Education Center in Uganda.
In Tanzania, KAIST students teamed up with NM-AIST students to carry out appropriate technology programs applied with Arduino kits. They plan to use scientific and engineering approaches to address local residents’ living challenges such as developing agricultural water suppliers using sensors measuring water in the soil and oxygen suppliers in the reservoir.
Meanwhile, in Ethiopia and Uganda, student volunteers will be involved in various ICT educational programs for local students. The volunteering corps will also introduce cultural programs including K-Pop dancing for young students there. They will also engage in sports and art classes for students at orphanages in the region.
President Sung-Chul Shin encouraged volunteers at the kick-off ceremony saying, “KAIST students should keep always humility, warmth, and tolerance in mind. I believe our students will exert leadership out there along with knowledge as well as wisdom.”
2018.07.02 View 6923