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Chemistry

Research

Towards future science and technology

Materials are often made up of molecules of sizes less than 1 nanometer (10-9 m). Molecular materials involve so-called nano-scaled substances consisting of several atoms. They also involve relatively large biological components, such as DNA and proteins. The research focus in chemistry is, therefore, on nano-scaled worlds including biological systems, together with the earth and the entire universe. Quantum mechanics, as it appeared in the 20th century, clarified that nano-scaled materials are controlled by scientific rules that are somewhat different from those we recognize in our everyday experiences. On the other hand, since the familiar double-stranded helix structure of DNA was first proposed by Watson and Crick in 1953, great advances have been made in the fields of bioscience. By the end of the 20th century, the human genome was almost completely sequenced. Recently, various biological phenomena have been interpreted in terms of molecular biology. The great advances in various analytical techniques have enabled the direct observation of nano-scaled worlds. These techniques are unveiling various molecular level events, together with the functionality of each molecule. Due to the rapid growth and advances in synthetic chemistry, a large variety of molecules that have various functionalities have now been developed. The structures of proteins that take advantage of biological reactions have been continuously resolved. As the mechanisms of the actions become clearer, rational design and syntheses of new drugs become feasible. As a result, various diseases are being overcome; therefore, there are increasing hopes that some incurable diseases might be defeated in the near future. Sanitation conditions have been greatly improved, enabling a higher standard of life for humans. Such a situation would never have been possible without the great advances in chemistry.

It is, however, difficult for chemists to have a perfect understanding of the molecules that can possess a wide range of properties and functionalities. For instance, due to the lack of basic knowledge in molecular sciences, it is still difficult for chemists to comprehend how a particular molecule recognizes another molecule, or how physical properties are altered when a molecule forms an association complex in solution. Furthermore, syntheses in chemistry have not overcome all problems; for instance, synthetic yields remain low in many cases. If we turn our attention to the issue of energy, the conversion efficiency of energy by artificial systems is only one tenth of that of solar energy converted by green plants. On the other hand, the emission of undesirable pollutants and the waste products produced by the chemical industry are major problems; both due to a lack of knowledge of the chemical properties of many substances, and to the use of inappropriate or imperfect synthetic methods. Such phenomena have recently come to threaten the limited resources and the natural environments found on Earth. The Earth is not only for our generation's enjoyment, but must also be passed over to future generations. Chemists need to find effective ways to save natural resources and to resolve problems arising from the chemical industry.

To preserve the rich environments on Earth, it is important to gain a better understanding of the chemical properties of substances and to utilize their functionalities. In this context, it is important to have a deeper knowledge about atoms, molecules, and the assemblies of molecules, and also to better understand the detailed mechanisms of how molecules and assemblies are yielded from their starting materials. It is also necessary to arrive at methods of achieving high safety standards and high convergence yields in syntheses, for it also establishes the basis of the continuation of civilization. To satisfy such social demands, research projects in our department aim at gaining deeper insights into the chemical properties of atoms, molecules, and assemblies, and at exploring new paths in chemistry leading to actual applications.

Unstable chemicals, reactive species, and properties of molecular recognition of chemicals have been investigated from both theoretical and experimental perspectives. The aim is to gain mechanistic insights into the chemical and physical properties of materials, to reduce the causes of environmental pollution, and to store knowledge for the fabrication of new drugs. In the field of coordination chemistry, the detailed properties of solutions have been investigated, and new compounds have been synthesized to develop new electronic systems, as well as new functional electronic materials. Moreover, efforts have also been made to develop solar energy conversion systems that generate molecular hydrogen from water under illumination from sunlight. Some of our colleagues have also been successful, presenting internationally outstanding research results. These have involved the introduction of innovative synthetic methods comparable to those in biological systems, the development of photofunctional materials, and so on. Unique attempts have also been made to clarify the circulation of materials on Earth from a viewpoint of geochemistry. Above all, our department is striving to contribute to the continuation of civilization through scientific research.

Education

Our Philosophy of Education

The world is made of matter. Chemistry is the science of matter based on theories and experiments for molecule and molecular assemblies. These theories and experiments give us new knowledge of molecular structures, transformation of materials, molecular recognition, and function of individual molecules and their assembly. Thus, chemistry helps to reveal the true make-up of matter, and allows us an improved understanding of the world. The essence of our mission is the quest for truth, and the conveyance of this philosophy to our students. The science and technologies of matter based on the molecular level is becoming ever more important. Developing leading scientists and engineers who have this philosophy, alongside the professional ethics and motivation to help shape human society in this century, is the aim of our education.

Undergraduate School

The department consists of 18 research groups and offers more than 30 elective lecture courses that cover a wide range of chemistry including inorganic, physical, organic, analytical, quantum, radio, and biological chemistry. Basic experimental exercises for inorganic, analytical, organic, biological, structural, and physical chemistry are targeted to second and third year students. These laboratory courses are obligatory. All fourth year students belong to one of the research groups, and they learn practical techniques relating to their own research subject and are required to pass an oral examination on the results of their research work. Members of the Institute for Materials Chemistry and Engineering contribute to the instruction. Most students go on to graduate schools to receive higher levels of education.

Graduate School

The department presently has 46 faculty members, all of whom participate in the graduate educational program and direct active research programs. Faculty members hail from widely different backgrounds, helping to contribute towards the enrichment of student life within the department.

The department's program of teaching and research area spans the breadth of chemistry. General areas covered include inorganic chemistry, analytical chemistry, organic chemistry, biochemistry, physical chemistry and physical chemistry for condensed matter. Specialized areas such as coordination chemistry, geochemistry, organometallic chemistry, quantum chemistry, biophysical chemistry, surface chemistry and chemical physics are also covered.

Some of the department's research activities are conducted in association with various interdisciplinary laboratories, such as the Institute for Materials Chemistry and Engineering. These interdepartmental research projects provide stimulating interaction among the research programs of several departments of Kyushu University and give students the opportunity to become familiar with research work in disciplines other than chemistry.

This spectrum of research activity, combined with a variety of challenging graduate subjects and an extensive seminar program, provides our graduate students with the solid foundation needed for a meaningful professional career and a lifetime of independent learning. It is this combination which makes the graduate in chemistry capable of adapting both to the changing demands of his or her profession and to future career opportunities.

Research Groups

Coordination Chemistry
  • Ken Sakai, Professor
  • Kosei Yamauchi, Assistant Professor
  • Hironobu Ozawa, Assistant Professor
Our group focuses on the realization of artificial photosynthetic molecular systems driving splitting of water (H2O) into H2 and O2 with use of solar energy (2H2O + 4 → 2H2 + O2). With this aim, we have performed the design and synthesis of new molecular catalysts based on metal complexes that can promote both water reduction and water oxidation processes in high turnover frequencies with lower applied overpotentials. In order to realize the hydrogen society, development of such fast catalysts that can function with low overpotentials is crucial in minimizing the input energy to drive the overall water splitting processes. This approach is directed to expand the wavelength range used for solar water splitting to a wider range that extends to a lower energy region of solar spectrum. Thus, our group targets development of new molecular catalysts that drive both water oxidation and reduction with a lower applied overpotentials. For their wide spread practical use in the future, catalyst development using cheap abundant non-precious metals, such as Fe, Cu, Ni, Co, etc., is also targeted in these studies. Improvement in the photoinduced electron transfer processes that generate reducing and oxidizing equivalents from solar light absorption is also targeted.
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Physical Coordination Chemistry
  • Masaaki Ohba, Professor
  • Tomomi Koshiyama, Assistant Professor
In the field of molecular materials, one of the important targets is the development of multi-functional material combining different properties and functions in a synergic way. Our group focuses on “coordination polymers” and “liposome” as a meso-scale platform for interlocking various functions and properties. The coordination polymers can provide functional space that consists of flexible, highly ordered and designable frameworks based on coordination bonds. The frameworks can be incorporated magnetic, electrical, optical and other properties, and also can adsorb molecules in the void of structure. The liposome, a spherical vesicle composed of a phospholipid bilayer, provides hierarchical composite with selectively incorporating different functional molecules into the hydrophilic inner water phase, hydrophobic lipid bilayer, and inner and outer surfaces. We are exploring advanced functions using such spaces with synergically linking plural different properties of components.
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Bioanalytical Chemistry
  • Nobuaki Matsumori, Professor
  • Masanao Kinoshita, Assistant Professor
We are studying biomembranes including membrane proteins using various analytical methods. The purposes of our study are to gain deeper understandings of biological membranes themselves, as well as to elucidate the molecular mode of actions of membrane-associated drugs and the pathogenic mechanism of membrane-related diseases such as Alzheimer disease.
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Spectrochemistry
  • Ken Onda, Professor
Our research interests are in the area of ultrafast spectroscopy of chemical reactions. Chemical reactions are the phenomena that materials are changed into other materials and their processes occur in the temporal range from femtosecond (10−15 sec.) to millisecond (10−3 sec.). Using ultrashort pulse lasers, we develop various types of time-resolved spectroscopy systems and investigate various functional materials, such as artificial photosynthesis and organic electronic devices, in-situ and in realtime.
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Analytical Chemistry
  • Kô Takehara, Associate Professor
The keyword of our group is to understand quantitatively the interaction between small molecules and biological systems. The current effort is focused on the physicochemical analysis of the interaction between bioactive small molecules, such as general anesthetics (GAs), and cell membrane components. For this purpose, the bioluminescence by bacterial luciferase (BL) was controlled by electrochemical method and applied it to analyze the inhibition mechanism of GAs to protein function; The binding properties of hydrophobic molecules to proteins were analyzed using spectrophotometric methods; The surface-modified electrodes were developed using self-assemble technique for the analysis of signal transfer mechanism in cell membrane.
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Inorganic Reaction Chemistry
  • Satoshi Utsunomiya, Associate Professor
The aim of my research is to understand the fundamental processes involving nanoparticles in various environmental problems that currently occur on the Earth surface. Specifically, I am interested in the property and behavior of natural and engineered nanoparticles in the ambient environments, their interaction with biological material such as microbes and human respiratory system, and geochemical and biochemical behaviors of toxic elements including radionuclides. Research topics frequently expand to nuclear waste management and atmospheric pollution.
Visit our web site, http://www.scc.kyushu-u.ac.jp/ircl/, for further information!
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Physical Chemistry of Interfaces
  • Makoto Aratono, Professor
  • Hiroki Matsubara, Associate Professor
The adsorbed film of surfactant has three distinct physical phases so called gaseous (G), expanded (L) and condensed (S) phases which is respectively corresponding to two-dimensional gas, liquid and solid states. When surfactant adsorbed films undergo two-dimensional phase transitions, which is normally driven by temperature, pressure, and concentration variations, the coexistence of surface phase domains can be observed. Our laboratory has studied the adsorption of surfactant at the air-water and oil-water interfaces more than 40 years and now we can set the physical state of interfaces as desired. One of the interesting findings of recent studies is the surface phase transition driven stability switching of foam and emulsion. The project on the relation between surface composition and foam film stability in binary surfactant systems is also in progress.
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Physical Chemistry of Soft Matters
  • Masahiko Annaka, Professor
  • Shintaro Yashima, Assistant Professor
We study the physical chemistry of soft condensed matter, which are easily deformable by external stresses, electric or magnetic fields, or even by thermal fluctuations. These materials typically possess structures which are much larger than atomic or molecular scales; the structure and dynamics at mesoscopic scales determine the physical properties of these materials. The goal of our research is to probe and understand this relationship. We study both synthetic and biological materials; our interests extend from fundamental physics to technological applications, from basic materials questions to specific biological problems.
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Quantum Chemistry
  • Akira TerasakiI, Professor
  • Kensuke HaradaII, Lecturer
  • Masashi ArakawaI, Assistant Professor
  1. Atomic and molecular clusters offer a unique opportunity to elucidate how physical and chemical properties of a matter emerge as atoms and molecules associate together one by one. We are interested, for example, in how ferromagnetism emerges for iron, cobalt, and nickel among 3d transition metals, whereas other elements do not exhibit it. For another example, silver nanoparticles are known to show strong photoabsorption, so-called surface-plasmon resonance, which is technologically important in coupling light with materials. However, one does not know how this picture works for small particles less than 1 nm in diameter. Furthermore, clusters provide a model of catalysts to gain molecular-level insights into mechanism of chemical reactions. We tackle these problems in materials science with single-atom precision toward advanced nano-science and technology.
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  2. Our group studies molecular structure and dynamics of transient molecules and molecular complexes with millimeter wave spectroscopy. We have developed a sensitive detection technique with multi-reflection optical path in millimeter wave region. We are observing rotational transitions as well as proton tunneling transitions of transient molecules and internal rotation transitions of molecular complexes in the millimeter wave region. Molecular structures as well as fine and hyperfine structures of radical species and intermolecular potential functions of molecular complexes have been determined by observed spectra. Recent research topics are as follows.
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Structural Chemistry
  • Kazuhiko Ohashi, Associate Professor
Molecular clusters and cluster ions are useful model systems for investigating intermolecular interactions at the microscopic level. Our group has been studying structures and dynamics of┬ámolecular clusters and cluster ions through spectroscopic experiments and theoretical calculations. Currently, we focus on the interaction between metal ions and solvent molecules. Our research subjects include (1) coordination and solvation structures of transition metal ions, (2) cooperation and competition between metal ion–solvent and solvent–solvent interactions, (3) comparison of coordination numbers between ions in the gas phase and in bulk solutions, (4) temperature effects on prevalent structures of solvated metal ions, (5) interaction of metal ions with biologically relevant molecules, and so forth.
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Molecular and Cellular Biochemistry
  • Osamu Kuge, Professor
  • Tadashi Ogishima, Associate Professor
  • Motohiro Tani, Associate Professor
  • Non Miyata, Assistant Professor
  • Xiaohui Liu, Assistant Professor
Our group conducts basic research examining the molecular and cell biology of lipids related to the problems of membrane and organelle biogenesis and intra- and inter-cellular signalings in eukaryotic cells. Other areas of investigation include physiological roles of local steroid hormones synthesized in the pancreas. We are currently working on (1) the mechanisms of interorganelle and intramitochondria transport of phospholipids, (2) the biological roles of complex sphingolipids, and (3) effects of nonsystemic or local steroids on the survival of ER-stressed pancreatic cells.
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Bioorganic Chemistry
  • Tohru Oishi, Professor
  • Kohei Torikai, Associate Professor
  • Makoto Ebine, Associate Professor
Interesting organic compounds called as natural products isolated from animals, plants, and microorganisms elicit potent biological activities by acting against cell membranes and certain proteins, and utilized as antibiotics and anticancer drugs. Our group studies about structure determination and total synthesis of bioactive natural products, elucidation of their target proteins and mode of action, and chemical biology based on design and synthesis of bioactive molecules.
Keywords: Natural Products, Biosynthesis, Structure Determination, Organic Synthesis, Total Synthesis, Chemical Biology
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Constructive Organic Chemistry
  • Yoshio Ito, Associate Professor
Physical organic chemistry of photochromism and synthetic organic chemistry are the main research fields in this laboratory.
Photochromism is the reversible process of absorption in some chemical substances. We are studying crystalline photochromism of N-salicylideneaniline derivatives. Recently, we developed organic solid solution method to observe other photochromic behaviors.
Asymmetric catalysis is useful for preparation of enantiomerically pure compounds where the stereochemistry plays an important role in the biological activities. Recently we have been focusing on development of environmentally benign organocatalysts.
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Structure-Function Biochemistry
  • Ayami Matsushima, Associate Professor
We have a strong interest in the molecular mechanisms of ligand-receptor interaction. There are many kinds of receptors on cell membranes, in the cytoplasm, in nuclei, etc. When a ligand binds to its specific receptor, it induces a conformational change in the receptor's structure and the signal is then transmitted. Our main research targets are nuclear receptors which precisely regulate gene transcription. We focus on all nuclear receptors to elucidate their activation mechanisms comprehensively. Binding affinity is analyzed in vitro by radioligand binding assays, and transcription activity is measured by reporter gene assays using cultured cells. The other targets are pain-modulating receptors, which are G-protein couple receptors (GPCRs).
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Theoretical Chemistry
  • Haruyuki Nakano, Professor
  • Norio Yoshida, Associate Professor
  • Yoshihiro Watanabe, Assistant Professor
Researches of our group is devoted to the theoretical chemistry based on the first principles of quantum and statistical mechanics. Our main research objective is to develop theoretical methods for electronic structures, properties, and chemical reactions of molecules, clusters, and molecular assemblies. Our focus is especially on the electron correlation theory for molecular systems, molecular theory of solvation, and relativistic molecular orbital theory. We develop mathematical methods, algorithms, and computer software, and approach various interesting chemical phenomena such as solvatochromism, co-solvent effects, and pKa of drug molecules.
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Catalysis Organic Chemistry
  • Makoto Tokunaga, Professor
  • Haruno Murayama, Associate Professor
  • Eiji Yamamoto, Assistant Professor
Our group studies both on homogeneous and heterogeneous catalysis. Particularly, as homogeneous catalysts, we have applied chiral quaternary ammonium salts for asymmetric ester hydrolysis for the first time. On the other hand, supported noble metal nanoparticles are investigated for heterogeneous catalysis. We are developing a novel preparation method of supported Au nanoparticles, reactions for bulk chemical transformation and fine chemical syntheses. In addition, adsorptive desulfurization from beverages and fuels have been investigated.
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Molecular Catalysis Chemistry
  • Ryoichi KuwanoI, Professor
  • Masahiko SuenagaII, Lecturer
  • Yusuke MakidaI, Assistant Professor
  1. We are developing novel and/or stereoselective organic reactions by using transition-metal complexes as catalysts. The new molecular transformations may lead to the discovery and creation of new materials and medicines, which may contribute the innovative progress of technology. We have realized on 1) the highly enantioselective hydrogenation of various heterocyclic and carbocyclic arenes, 2) the palladium-catalyzed substitution of benzylic carboxylates and carbonates with various nucleophiles, 3) the palladium catalyzed [4 + 2] cycloadditions of o-(silylmethyl)benzyl carbonates, 4) the rhodium-catalyzed reactions of alkenyl acetates, and 5) the nickel- or palladium-catalyzed oxidative β-aminations of ketones and related compounds. Furthermore, we are studying on the reaction mechanism of the above catalytic reactions.
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  2. My first research interest is a development of GUI (Graphic User Interface) for molecular modeling and computational chemistry software (such as TINKER, MSMS, Firefly, Gamess, MOPAC and Gaussian). Since 2004, I have developed GUI software, Facio, and opened it to the public as freeware, with a hope that it will be helpful to study and research on theoretical chemistry. In addition to the educational purpose, this software is indispensable to FMO (Fragment Molecular Orbital) study, since it is the only GUI for FMO-specific input and output.
    My second research interest is to re-examine fundamental concepts in organic chemistry, such as steric hindrance, using NBO (Natural Bond Orbital). While MO (Molecular Orbital) views various molecular properties as a whole, NBO can view them as interaction between localized donor orbital and acceptor orbital providing a different viewpoint to organic chemistry.
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Chemical Physics and Biophysics
  • Ryo Akiyama, Associate Professor
Various chemical and biological phenomena, such as molecular motor, proteins' association, and electron transfer reaction, are studied on the basis of physics in our group. We are interested in medium effects, such as solvent effects. Those effects have been recognized to be minor. However, media often change the fates of solutes drastically. Actually, proteins work only under certain thermodynamic condition, and stabilities of colloidal dispersion systems are regulated by the system temperature, the salt concentration, and so on. And, those phenomena relate to the biological functions. We are basically interested in those phenomena. Our main tools are thermodynamics, statistical mechanics and numerical calculation by using computers, such as molecular simulations.
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Nanomaterials and Interfaces
  • Kaoru Tamada, Professor
  • Koichi Okamoto, Associate Professor
  • Sou Ryuzaki, Assistant Professor
Our group studies about the interfacial phenomena between metals, metal oxides, semiconductors and soft materials in nanoscale. Our research target is not only to investigate new physicochemical phenomena on cutting edge of interdisciplinary field of science, but also to develop the new concept for future green and bio-technologies. Our topics include (1) Collective plasmon excitation on 2D crystalline sheets composed of Au and Ag nanoparticles, (2) High sensitive biosensor and high resolution bioimaging by use of localized surface plasmons, (3) Surface plasmon enhanced optoelectric devices such as light-emitting diodes (LEDs) and photovoltaic cells.
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Photofunctional Materials Chemistry
  • Osamu Sato, Professor
  • Shinji Kanegawa, Assistant Professor
  • Soonchul Kang, Assistant Professor
The development of functional molecular compounds for use in molecular electronic devices is an important challenge in the field of materials science. Our group aims to synthesize switchable materials with superior physical properties by controlling electron transfer, spin configuration, orbital movement, proton transfer, and molecular orientation in molecular crystals. In particular, we are currently focusing on the development of magnetic, conducting, ferroelectric, and mechanical materials whose properties can be controlled by external stimuli such as light and temperature. These switchable compounds can be used in future applications such as memory devices and optical switches.
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Structural Organic Chemistry
  • Fumito Tani, Associate Professor
  • Kenta Goto, Assistant Professor
  1. Synthesis and function of supramolecular structures based on organic p-electron compounds.
  2. Photoinduced electron transfer and high charge mobility in porphyrin-fullerene supramolecules.
  3. Synthesis and photoelectronic properties of novel polycyclic p-electron compounds.
  4. Photomechanical effect and photochemical reaction of aromatic diimides.
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Soft Interfacial Chemistry
  • Takanori Takiue, Professor
  • Yosuke Imai, Assistant Professor
The soft interface such as gas/liquid and liquid/liquid interfaces is regarded as a fundamental structure of soft matters including emulsion, vesicle, biological membrane, and thus the study on the structure and property of soft interface is crucial to understand sophisticated structure-function relation of soft matter. Our group investigates the adsorbed films (Gibbs films) of various surface active substances at soft interfaces by means of macroscopic and microscopic techniques; interfacial tensiometry, synchrotron X-ray reflection (XR), total reflection XAFS, and Brewster angle microscopy (BAM). Our goal is to elucidate the principles of “raft” formation in biological membrane from the viewpoint of “line tension”, which is an excess energy generated at the domain boundary in heterogeneous structure at the interface. Our recent activities are as follows.
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Biomolecular Chemistry
  • Takeru Nose, Professor
  • Keitaro Suyama, Assistant Professor
  • † Faculty of Arts and Science
Our laboratory mainly studies three subjects that are focus areas in peptide and protein chemistry research. These are as follows: (1) structure-function relationship of elastin-derived peptides; (2) determination and discovery of receptor-binding molecules, in particular, risk assessment of endocrine disruptors using a combination of computational and biochemical techniques; and (3) rational molecular design of enzyme inhibitors.
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Synthetic Organic Chemistry
  • Tatsuya Uchida†‡, Associate Professor
  • † Faculty of Arts and Science
  • ‡ International Institution for Carbon-Neutral Energy Research
Organic synthetic reactions are quite important and fundamental technologies for the supplying various materials. However, most of organic transformations are consumed a lot of materials and energies with co-producing undesired waste materials. Development of highly selective, atom-economic and environment-friend new methodologies have been strongly required.
For the purpose of these viewpoints, we have intrigued to oxidative catalytic functionalization using high atom-economic oxidant, and achieved that highly enantioselective water-mediated epoxidation using air as an oxidant, and asymmetric nitrene transfer reaction using azide compound as a nitrene source.
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Nanofunctional Chemistry
  • Miho Yamauchi, Professor
  • Masaaki Sadakiyo, Assistant Professor
  • ‡ International Institution for Carbon-Neutral Energy Research
We synthesize nanometer-seized materials to exhibit high functionalities in catalysis, ion conduction, gas storage and magnetics for the realization of sustainable society. Electric structures, compositions and morphologies of the materials composed of alloys and oxides nanoparticles are controlled to achieve highly efficient energy and material conversions. Composite materials of porous coordination polymers demonstrate novel catalytic and ion conduction abilities through cooperative interactions among ligands and metal species. Prepared nanomaterials are applied as a device for electric power charge/discharge, catalytic materials transformation, hydrogen storage and permanent magnetism. Our final goal is elucidation of guiding principles to realize functionalities of materials and demonstration of higher functionalities based on our own principles.
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Environmental Radiochemistry
  • Shinji Sugihara§, Associate Professor
  • § Central Institute of Radioisotope Science and Safety Management
Our group studies on environmental behavior of radionuclides in relation to chemistry and development of analytical procedure for radionuclides in the environment.
Resent Research Topics:
  1. Environmental behavior studies of the radioactive isotope of hydrogen: “Tritium”
  2. Environmental behavior studies of the radioactivity released into the environment due to the Fukushima Nuclear Power Plant accident.
  3. U-series dating of speleothems in limestone caves.
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