Total 16Articles
News list
Content Forum List
2017-04 03 Important News

[Academics][Researcher of the Month] Detecting Ultra-Sensitive Benzene

Professor Kim Hyoun-woo of the Division of Materials Science and Engineering is April’s Researcher of the Month, for his active role in exploring the field of materials science and engineering. In his paper “Ultra-sensitive benzene detection by a novel approach: Core-shell nanowires combined with the Pd-functionalization”, Kim explains how the detection of benzene gas has become much more efficient than ever. The palladium being extra sensitive to benzene gas has been the key to the detection technique which has drawn attention in this field. Kim has discovered the link between palladium and benzene gas. The Pd-functionalized SnO2-ZnO C-S NW is the substance developed by Kim in order to detect benzene, a toxic gas. Since nano-sized palladium particles are added on a cell with SnO2 and ZnO covered on top, the sensor produces a spillover effect, distributing the benzene gas particles along the conduction band. The effectiveness of Kim's model is proven through the gas response. (Photo courtesy of Kim) This is important since benzene gas can be found in everyday life. It is inside cigarette smoke, smog, exhaust fumes and may be found in new houses, creating sick house syndrome. Through Kim’s finding, this benzene gas, which could be lethal to human lives, can be spotted in a much more sensitive manner. Since the sensors and cells created in a smaller size would lead to higher sensitivity, the particles have been selected in nano-sizes. The only problem that could arise with this sensor is that it depends heavily upon the selectivity of which gas it wants to detect. The compatibility between different particles could create great results as Kim has found out in the case of palladium and benzene, while in other cases, disastrous results may be spawned. Kim explains how his model works. Kim wishes to develop better usage of sensors than those that are being distributed in every day life as of now. “I want to find the best usage of a new sensing principle totally different from the current ones,” said Kim. Kim Seung-jun nzdave94@hanyang.ac.kr Photos by Choi Min-ju

2017-02 28 Important News

[Academics][Researcher of the Month] Blue Ocean of Materials Science

Conspicuous or not, our surroundings play a crucial role in navigating our health, holding accountability for small and big degenerations for mankind’s physical wellbeing. Among all, two indispensable elements in our life, air and water, have slow and accumulative effect on the health of the population. Professor Kim Ki-hyun (Department of Civil and Environmental Engineering), whose studies focus on environmental pollution, delineated the means of applying advanced materials in his review paper “Carbon nanotubes: a novel material for multifaceted applications in human healthcare.” Carbon nanotubes in biotechnology As modern material technology has been advancing considerably, its application seems ever-expanding in diverse fields, with nanomaterials as the convenient and indispensable companion. Based on a research paper conducted by other scholars, Kim wrote another, centralizing on the uses of carbon nanotubes (CNT), an emerging nanomaterial that is seeing the light in the biomedical and environmental fields. Its application is versatile: drug delivery, sensing, water purification, composite materials, and bone scaffolds. More specifically, CNTs could be used to alleviate myocardial infarction by enlarging clogged blood vessels, expediting drug delivery, and organizing bone structures in needed parts. Kim outlines his review paper on the application of carbon nanotubes in the biomedical field. Despite all the medical benefits, advanced materials including CNT also have the potential to bring adverse effects. As alien substances could disturb immune or antibody responses, the body functions to react against them. Especially, in case of new materials, unprecedented resistance could occur, and thus their potential impacts must be taken into consideration through attentive examination for possible toxicity. Nonetheless, as long as the criteria are met, CNT and other materials could spark revolutionary breakthroughs that would change the future of mankind. “I think that endless developments are yet to come in the field of materials science to help other research fields like environment and human health flourish. Better materials in terms of cost efficiency and functional effectiveness would be improved while there is yet no limits to such developments. Materials science and nanomaterials would not only be fruitful in biomedical fields but also environmentally,” commented Kim. His interest in new materials are extended toward environmental progress, starting with the sensing of pollutants and purifying polluted medium. The blue ocean Materials science could often be referred to as the 'blue ocean' since there are more to be discovered than what has been excavated so far. On top of this, collaboration with environmental issues is not conventional. Kim is involved in research for integrated environmental monitoring technology, digitizing and managing air, water, and soil pollution. He is looking forward to fuse newly unveiled materials in his research, hoping to bring a constructive result to lay a bridge between materials science and environmental engineering. To set an example, metal-organic frameworks (MOFs) could be used to mitigate environment pollution: volatile organic compounds (VOC) in the air spawns odor while propagating carcinogens if transferred into the human body through the respiratory system. As the material for sensing or removing such hazardous pollutants, MOFs are regarded as one of the highly promising solutions. What is to be underscored here is the infinite possibility of combination of the materials, which are not only capable of being used alone but also of being employed in cooperation with other materials. Kim's research will continue to be centered around mitigating environmental pollution with newly excavated materials. Jeon Chae-yun chaeyun111@hanyang.ac.kr Photos by Choi Min-ju

2017-02 06

[Academics][Researcher of the Month] Al-FCG Ready for Action

Professor Sun Yang-guk of the Department of Energy Engineering is February’s Researcher of the Month for his active role in exploring the field of energy engineering. In his paper, “Compositionally Graded Cathode Material with Long-Term Cycling Stability for Electric Vehicles Application”, Sun explains how adding aluminum into the cathode makes batteries last longer and become more stable compared to other rates of composition. The Al-FCG61 that Sun has developed has shown a high rate of energy efficiency even at 100% depth of discharge (DOD), which draws attention in the field. Sun explains his research with assisted diagrams. As the supply and demand of the electric vehicle is on the rise, most of the batteries in the market last from 150km to 400km, meaning that once the battery is fully charged, the car would move between the distance within. What accounts for the difference is the capacity as to how much cathode can hold up. In order for cars to go beyond 300km at least, the capacity of the cathode would have to be over 200A/h. The only problem to this is that it gets difficult to make it stable and it could blow up. There are various prototypes ranging from generation 1 to generation 4 and the study carried out in Sun's paper is on generation 3. Gradients of different components from inner to outer parts of nickel particle. (Photo courtesy of Sun) Capacity retention, which is the lifespan of a battery, would rise with 61% of nickel with FCG full concentration gradient, which is what Sun has developed in order to create a more stable and long-lasting battery that would hold a larger capacity. Within the mold, Sun has created a two-way particle that contains a high percentage of nickel inside with lower percentage of nickel on the outside. This concentration gradient is created due to the fact that nickel has its advantage of being able to increase the capacity of the battery while it makes the battery more unstable with exothermic reaction. Along with the nickel, Sun has increased the percentage of the manganese inside the particle since it has the advantage of making the cathode more stable. Depth of discharge (DOD) is the rate at which battery is either charged 60% or 100%, and this is tested before electric vehicles are sold for inspection. The average usage of an electric vehicle is at around 2,500 cycles for 10 years, and the Al-FCG has proven to be more energy efficient even at 100%. Most of the batteries do not last long at DOD100 due to the expansion of volume inside the battery. This means that the battery would lose its efficiency as time goes. Al-FCG has shown its Coulombic efficiency rate of 84.5% even at DOD100, while batteries currently in the market show an average of 50% at 2000 cycles. This new battery devised by Sun is not only more energy efficient, but more cost efficient as well. Sun wishes to make more efficient batteries. Sun is continuously researching to keep the DOD level at 100% even after 2000 cycles. With his findings, the electric vehicle industry would definitely benefit hugely in terms of cost and energy efficiency. With different materials, Sun wishes to develop other types of batteries that would bring more comfort to society. Kim Seung-jun nzdave94@hanyang.ac.kr Photos by Kim Youn-soo

2017-01 02 Important News

[Academics][Researcher of the Month] Scientific Integration Approach to Programmable Nuclease (1)

When a baby is identified to have been born with a rare, incurable disease, it would bring about concerns and sorrow to the newborn and the parents. However, with the prospective research on CRISPR Cas-9 system, or a programmable nuclease, a host of diseases will prevented without further ado. Professor Bae Sang-su of the Department of Chemistry explains the mechanism of the CRISPR Cas-9 system through his research “Structural roles of guide RNAs in the nuclease activity of Cas-9 endonuclease”. Also, he reveals the course of his life towards scientific integration that shapes the bright future of scientific studies. Structural properties and significance of CRISPR Cas-9 The significance of this research paper is that it explains the structural mechanisms of the CRISPR Cas-9 system and how it can modify or edit DNAs in cells. CRISPR-Cas 9 stands for Clustered Regularly Interspaced Short Palindromic Repeats, which relies on a protein named Cas-9. As it is called by the name of 'molecule scissors', it introduces the new spectrum of genome editing technology. Even though there already have been two programmable nuclease systems which are the Zinc Finger Nuclease and the TALENs(Transcriptor Activator Like Effector Nuclease System). The former is the first generation of the genome editing system that is compiled of one zinc finger and three to four nucleases. The title originated from the chemical component zinc, because this DNA contained certain amount of zinc. Then the second generation of genome editing system developed, which was called the TALENs that contained the base named xanthomonas originating from vegetable pathogens. “These two generations were startling contributions to scientific development, but with the advent of the third generation of genome editing, the CRISPR Cas-9 system, the scientific world could not contain its surprise,” said Bae. The CRISPR Cas-9 system was simpler in application to various circumstances and in the modification of DNAs. The significance of the CRISPR Cas-9 system is that it can enhance the welfare of human life in various aspects. “This technology is currently being applied to plants and animals, and also is in process of availing itself to humans by amending laws. Application of the system to humans will take 10 years at the most, since the research is developing at a fast pace,” explained Bae. An example of genome-modified plant through the CRISPR Cas-9 system that Bae provided was a modified mushroom in the United States. Discoloration of mushrooms by time lapse was prevented due to the CRISPR Cas-9 system, and the mushroom could maintain its original color for a long time. Bae explained that “not only does the CRISPR Cas-9 system treat incurable diseases of humans, but it can also modify DNAs in plants and animals to increase marketability.” Bae is explaining the significance of the CRISPR Cas-9 system. However, the genome editing system has been controversial in the scientific academia due to its resemblance to genetically modified organisms, also called GMO. According to Bae, there is a blunt difference between the two because GMO requires DNAs extracted from other organisms to modify the sample, while the CRISPR Cas-9 system modifies DNAs in the sample itself. “Even though some experts call the CRISPR Cas-9 system a part of GMO, the American Food and Drug Administration has acknowledged the genome editing program as a discrete system,” said Bae. Another controversy that the CRISPR Cas-9 system is incurring is the occurrence risk of a tailored baby. Even though there is a low possibility in creation of so called 'monsters', the prospect of the system is inexhaustible that the scientific academia can’t forecast the future application of the CRISPR Cas-9 system. “The application of the system should be discreetly considered and contemplated, in order to prevent any accounts of abuse incurred by a little crack of regulations,” said Bae. Scientific integration approach and its synergy effects One of the reasons why Bae could successfully reveal the mechanism of this newly found technology was due to his academic background. Bae got his bachelor’s, master’s, and doctoral degrees in physics, while pursuing chemical studies in his post-doctoral program. Once he became a professor in the chemistry department, he encountered the Method of the Year- 2013 published by Nature Method, which was introducing the new technology, the CRISPR Cas-9 system. As Bae was carried away by the astonishment, he got involved in the genome engineering research in earnest. “Although there could be some drawbacks for me to research biological technology because I majored in physics and chemistry, I thought that I can sublimate these flaws into advantages through scientific integration,” said Bae. Because he majored in physics, he could access the research in a physician’s perspective of ‘how and why’, instead of a biologist’s perspective of ‘so.’ According to Bae, he demonstrated his full potential and capabilities in this research as both physician and chemist, because he could inquire the structural mechanisms of the system and create programs using various physical means like razors. In his teenage years, Bae was interested in studying science since he was a student of natural sciences and engineering. Moment by moment, Bae immersed himself in scientific research, and in his graduate school years, he spent great energy and time researching for scientific development. Due to his diverse academic background, Bae could successfully pursue his amalgamative research in different scientific fields. Now, another approach to scientific integration is in progress, as the CRISPR Cas-9 system is being applied to different fields. “As a scientist researching the CRISPR Cas-9 system, I have to cooperate with experts from profoundly dissimilar fields. Lack of knowledge between each others’ academic branches and hardship in communication may bring about discord. Thus, efforts to understand and study each others’ academic knowledge through cooperation is the key to successful results,” said Bae. A scientific integration approach has been the key to successful research on the CRISPR Cas-9 system. Bae's ultimate goal is to apply this original research of CRISPR Cas-9 system to different fields through joint research. To the question of how he will encourage and foster junior scholars at Hanyang University, he answered with ‘confidence.’ “I have studied and researched at various universities with different experts, and I have realized that students of Hanyang University are equally capable to these scientists. With confidence and courage to carry on their majors with tenacity, students of Hanyang University can demonstrate their capabilities to the fullest,” said Bae. Kim Ju-hyun kimster9421@hanyang.ac.kr Photos by Kim Youn-soo

2016-11 01 Important News

[Academics][Researcher of the Month] Professor Paik Un-gyu

Professor Paik Un-gyu of the Department of Energy Engineering is November's Researcher of the Month for his active role in exploring the field of energy engineering. Recently, he has led a research team in developing significant improvement of sodium-ion batteries (SIBs), explained in the paper, 'SB@C coaxial nanotubes as a superior long-life and high-rate anode for sodium ion batters'. This specific study focuses on ways to increase the efficiency of the sodium-ion battery, which can possibly replace the popular lithium-ion batteries. Paik spoke about his study as well as his experience as a professor. (Photo courtesy of Paik) “There are other excellent professors who deserve this honor for than me. Yet, I am still very thankful for it,” said Paik. “The research was about sodium-ion batteries, which is rarely known to the public. The main objective was to reduce problems and improve effectiveness of sodium-ion batteries to replace lithium-ion batteries in the future.” Currently, lithium-ion batteries are commonly used in various electronic devices including smartphones. However, the main problem of lithium-ion batteries is the cost of lithium itself. There are certain limits for the Korean government to secure enough lithium mines from overseas. Therefore, a more parallel, affordable solution is to replace lithium with sodium in making ion batteries. Similar to lithium-ion batteries, sodium-ion batteries have issues of rapid operating-capacity fading due to large volume expansion during sodiation. Sodiation is the process of using sodium for a battery. Smartphone batteries bubbling up like a balloon is an example of volume expansion in lithium-ion batteries. “To reduce volume expansion, we tuned the morphology and structure at the nanoscale using carbonaceous materials as the buffer layer,” explained Paik. “Hence, a carbon-coating with a thermal reduction strategy was developed to create a unique tube-like structure, known as Sb@C coaxial nanotubes.” In other words, the hollow space within the specially-created tube can make space available for the accommodation of volume expansion. Another way to increase sodium-ion batteries' efficiency is to improve the charge and discharge system. The charging speed of a battery depends on electron conduction; how fast electrons move within its electric field. Carbon-coated nanotube, a conduction material, allows the conduction of electrons to quicken and enables diffusion to take place, making both sides of the tubes accessible for the charging system. Therefore, by reducing the risk of volume expansion and enhancing the charge system, sodium-ion batteries can be applicable in replacing lithium-ion batteries. The nanotube enhances the quality of sodium-ion batteries. (Photo courtesy of RSC Publisher) Other than this specific study, Paik has contributed immensely in researching applicable, practical studies of nanoparticles and nanodevices used in semiconductors. Most of his studies focus on what can be done to improve technology by working with industries in various sectors. “I personally believe that the reason why I am a researcher is to find practical ways to help the society. The fundamental studies are also important, but I tend to use the basic principles to apply them to real and effective technology,” said Paik. His passion for energy engineering has led him to become one of the professors to have published the most research papers at Hanyang University. Like his accomplishment in energy engineering research, Paik emphasized the need for passion for students who strive for success. “Today, we are facing a more skill-intensified society where work requires advanced expertise in an area. As learners, students must have passion for studying,” said Paik. “Even though the society is rapidly changing at each moment, if students take consistent steps through learning, it can be a strong benefit for them once they have amassed required knowledge.” As a professor, Paik has guided many students in taking the same steps that he himself has gone through for the past 24 years of learning and researching. “In science, understanding the boundaries of each important experiment is necessary, which must be overcome to produce an outcome. Likewise, I hope my role as a professor can assist students to overcome those limitations.” As a professor, Paik guides students to strive for success. (Photo courtesy of Paik) Park Min-young minyoungpark118@gmail.com

2016-10 03

[Academics]How Students Engage in Class

Professor Jang Hyung-shim of the Department of Education recently published a paper titled “Why students become more engaged or more disengaged during the semester: A self-determination theory dual process model.” She was consequently nominated as Researcher of the Month at HYU. Professor Jang's achievement lies in understanding the motivational processes of student learning and how it is affected by social contexts. More specifically, the research focuses on the relationship between instructors’ motivation styles and students’ functioning abilities in the classroom. Jang, an experienced expert in the specific field of study, spoke about the cause-and-effect relationship between the two subjects. Instructors, specifically school teachers, play a crucial role in student behavior and participation in academics. There is a common understanding, based on past studies, that if the instructor is more authoritative, teaching based on strict rules and procedures, student involvement in class decreases. In contrast, if the instructor provides more autonomous support in education, then students tend to be more engaged in class. The autonomous teaching method emphasizes freedom in a classroom, allowing creativity and critical thinking to flourish. Thus, in this specific study, Jang proposed a new perspective, a dual process model, in the existing self-determination theory. Guiding Jang’s research as a theoretical base, self-determination theory explains how students learning through self-motivated or autonomous learning increases their engagement in class. “The special finding in this research is in the dual process model. We have found out that for an individual student and an instructor, there are two ways in which they are affected by each other,” explained Jang. “For example, students’ engagement in learning can be explained by their experience of week-to-week gains in their need satisfaction guided by the instructor.” In short, the need satisfaction concerning a single student is achieved through autonomous support of instructors. Need frustration or disengagement, on the other hand, is the result of an authoritative instructor. Thus, the dual process within an individual student is shown, totally influenced by social context, which is the relationship with the instructor. Jang is an expert in education who has published numerous papers on improving the education system. Moreover, the findings confirm the existence of reciprocal causality in the classroom. “The reciprocal relation between authoritative teaching and student disengagement is quite strong, as controlling teachers lead to disengaged students and disengaged students lead to controlling teachers,” said Jang. “The reciprocal relation between autonomy-supportive teaching and student engagement is there, but is less strong.” This interesting relationship between students and teachers demonstrates the intertwined roles that influence each other either positively or negatively. “The research was completed using a three-wave longitudinal research with 366 high school students in Seoul participating. A questionnaire was given to each them three times at different points throughout the semester,” said Jang. The questions included a statement of consent, measures to assess the need satisfaction and need frustration, as well as autonomy support and teacher control. After the second stage of data analysis, the results showed the current finding based on the information collected. Jang believes that the results of this study has a lot to offer to both the students and teachers. “The teachers must improve styles of motivation based on two distinct skills. One of them is to have more supportive autonomy and the other is to be less controlling. Also, students must realize that classroom disengagement affects teachers’ motivating style toward them, and this is a rather strong effect,” said Jang. “So if your teacher is oppressive toward you, one reason may be because you are manifesting strong disengagement.” Thanks to the effort of researchers like Jang, necessary improvements continue to proceed in the Korean education system. In that sense, Hanyang University also stands as a leading global institution that is open to change and reform. This study will guide the Korean educational system towards a new transformation. Park Min-young manutdmin@hanyang.ac.kr Photos by Choi Min-ju