Article
Chemistry, Multidisciplinary
Rebecca L. Spicer, Helen M. O'Connor, Yael Ben-Tal, Hang Zhou, Patrick J. Boaler, Fraser C. Milne, Euan K. Brechin, Guy. C. Lloyd-Jones, Paul J. Lusby
Summary: Coordination cage catalysis is a strategy that utilizes a cage as an exogenous catalyst, rather than relying on the endogenous binding of substrates. The cage alters the properties of a cofactor guest, which then transfers reactivity to the bulk-phase to catalyze reactions.
Review
Chemistry, Multidisciplinary
Matthias Schmalzbauer, Michela Marcon, Burkhard Koenig
Summary: Utilizing photoexcited anionic species in organic synthesis has great potential to open up novel and unique pathways in organic chemistry, leading to more sustainable and atom-economic chemical processes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Supriya Halder, Sourav Mandal, Ayanangshu Biswas, Debashis Adhikari
Summary: Naphthalene monoimide (NMI) molecules have been discovered to be powerful reductants that can trigger strong C-Cl bond cleavage reactions. Under photochemical conditions, these molecules exhibit high efficiency in dehydrogenation reactions. Upon photoexcitation, NMI can be easily reduced by (KOBu)-Bu-t, leading to efficient dehydrogenation processes.
Article
Chemistry, Physical
Lan Nguyen Tran, Eric Neuscamman
Summary: This study uses the recently developed W & UGamma;-CASSCF method to investigate the ligand-to-metal charge-transfer states of ferrioxalate photolysis. The results are consistent with recent experiments and clarify some features that are not observable in experiments. The photolysis of ferrioxalate involves the cleavage of one Fe-O bond first, followed by the C-C bond and the other Fe-O bond.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Micheal M. Alowakennu, Atanu Ghosh, James K. Mccusker
Summary: This study provides direct evidence of the highly oxidizing nature of the lowest-energy ligand-field excited state of a first-row d(6)-low-spin Co(III) photosensitizer. The redox potential associated with the excited state was determined through quenching studies and time-resolved absorption spectroscopy. The results indicate that this class of chromophores has stronger excited-state properties compared to commonly used transition metal-based photoredox agents, making them suitable for activating oxidatively resistant organic substrates in photoredox catalysis.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Shaohua Zhang, Yishan Zhang, Yu Chen, Dong Yang, Shihao Li, Yizhou Wu, Yiying Sun, Yuqing Cheng, Jiafu Shi, Zhongyi Jiang
Summary: The metal hydride-embedded titania coating plays a crucial role in protecting enzymes and facilitating electron transfer, leading to a significantly higher methanol production rate compared to systems without the coating. This coordinated photo-enzymatic system demonstrates potential for efficient solar chemical conversion.
Article
Chemistry, Organic
Xing-Zhuo Shao, Guo-Yong Xu, Weigang Fan, Sheng Zhang, Man-Bo Li
Summary: A photochemical strategy using amines as reducing agents was developed for the mild and selective reduction of nitroarenes, forming isoxazolidine derivatives with high efficiency. This work provides an efficient way for the construction of isoxazolidine derivatives and opens up new opportunities for the application of photoactivation of nitroarenes and amines.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Nathalie Body, Robin Bevernaegie, Corentin Lefebvre, Ivan Jabin, Sophie Hermans, Olivier Riant, Ludovic Troian-Gautier
Summary: This study presents a novel approach for the immobilization of homoleptic and heteroleptic copper(I) complexes on silica nanoparticles, which are used as catalysts in visible-light mediated photoredox reactions. The photophysical properties of the immobilized photosensitizers are largely preserved, and efficient excited-state quenching occurs with aryl diazonium derivatives. The alpha-arylation reaction using the immobilized homoleptic complex shows moderate but similar yields compared to the homogeneous conditions. Importantly, the silica-supported photocatalysts can be recycled with moderate loss in photoactivity over multiple experiments.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Environmental Sciences
Xi Li, Xiao Zhang, Shiwen Wang, Peng Yu, Yanhua Xu, Yongjun Sun
Summary: By synthesizing an Fe/SCN catalyst, electron-hole recombination can be suppressed and electron transfer can be enhanced, achieving efficient degradation of tetracycline. This study provides a new perspective for the design of metal-doped heterogeneous Fenton catalysts for the efficient degradation of antibiotic contaminants in water.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Chemistry, Physical
Shuai Xu, Hua-Jian Lin, Xin Lin, Xiao-Yan Fu, Shuo Hou, Zhi-Quan Wei, Qiao-Ling Mo, Fang-Xing Xiao
Summary: This study unveiled the enhanced charge transfer efficiency of TMCs QDs by constructing multilayered heterostructures with non-conductive PDDA layer as an intermediate layer, leading to selective anaerobic reduction of nitroaromatics. The novel structure provides a promising design direction for solar energy conversion systems.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Inorganic & Nuclear
Moritz Heindl, Jiang Hongyan, Shao-An Hua, Manuel Oelschlegel, Franc Meyer, Dirk Schwarzer, Leticia Gonzalez
Summary: The study reveals that extensive structural relaxation within the sulfurated bpy ligand leads to the formation of a single long-lived excited state, independent of the excitation wavelength.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Luca D'Amario, Maria Bruna Stella, Tomas Edvinsson, Maurizio Persico, Johannes Messinger, Holger Dau
Summary: This study describes a transient spectro-electrochemical Raman setup that achieves sub-ms time resolution, allowing for the study of electrochemical processes. The technique was validated through experiments and confirmed to be effective in assigning spectral properties to transient species. This research provides a foundational contribution to the development of next generation electrolizers, fuel cells, and batteries.
Article
Chemistry, Multidisciplinary
Bjorn Pfund, Valeriia Hutskalova, Christof Sparr, Oliver S. Wenger
Summary: By modifying acridinium dyes, a new family of organic photocatalysts called isoacridones was obtained, which have both photoactive singlet- and triplet-excited states. These isoacridone dyes have high intersystem crossing efficiencies and can store significant amounts of energy. They can be used for parallel triplet-triplet energy transfer and photoinduced electron transfer, making them suitable for modern photocatalysis. In proof-of-principle experiments, the isoacridone dyes demonstrated their potential for applications such as arene reductions and C-C couplings. Additionally, by combining with an annihilator, sensitized triplet-triplet annihilation upconversion was achieved.
Article
Chemistry, Multidisciplinary
Yunxiu Bai, Pengqian Luan, Yunpeng Bai, Richard N. Zare, Jun Ge
Summary: Enzyme-photo-coupled catalysis combines the selectivity of enzymes with the energy input of sunlight to produce fine chemicals. However, large-scale operation faces challenges such as enzyme activity loss and efficient utilization of solar energy. This study presents a large-scale enzyme-photo-coupled catalysis system using gas-sprayed microdroplets, which significantly improves solar energy utilization and enhances enzyme activity for the production of chiral alcohols.
Article
Physics, Multidisciplinary
Shadi Fatayer, Florian Albrecht, Ivano Tavernelli, Mats Persson, Nikolaj Moll, Leo Gross
Summary: By using single charge injections with an atomic force microscope, redox reactions of a molecule on a multilayer insulating film were investigated. Three channels for neutralization were observed and corresponding to transitions to different excited states. Energy differences between these transitions were measured using single-electron tunneling spectroscopy, and compared with density functional theory calculations. The results show that excited states of molecules can be prepared and their optical gap energies can be quantified through controlled single-charge injections.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Ken-ichi Yamanaka, Kosuke Sato, Shunsuke Sato, Shunsuke Nozawa, Sunghee Lee, Ryo Fukaya, Hironobu Fukuzawa, Daehyun You, Shu Saito, Tsukasa Takanashi, Tetsuo Katayama, Tadashi Togashi, Takamasa Nonaka, Kazuhiko Dohmae, Shin-ichi Adachi, Kiyoshi Ueda, Makina Yabashi, Takeshi Morikawa, Ryoji Asahi
Summary: The visible-light excitation process in a known CO2-reduction photocatalyst was investigated using TR-XANES spectroscopy. Ultrafast intersystem crossing and the excited state lifetime of the metal-to-ligand-charge-transfer state were observed.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2023)
Article
Computer Science, Artificial Intelligence
Amanul Haque, Nirav Ajmeri, Munindar P. Singh
Summary: It is well recognized that the Web has an impact on user polarization, which extends beyond politics and affects public health matters such as vaccination. Understanding polarization in social networks is a complex task as it depends not only on user attitudes but also their interactions and exposure to information. By adopting the Social Judgment Theory and empirical evidence from previous research, we created a social simulation to examine the effects of content sharing on user satisfaction and polarization within a social network. Our findings demonstrate that (1) higher user tolerance decelerates polarization but leads to lower user satisfaction; (2) increased selective exposure results in higher polarization and limited user reach; and (3) both higher tolerance and selective exposure contribute to a more homophilic social network.
Article
Computer Science, Software Engineering
Munindar P. Singh, Pradeep K. Murukannaiah
Summary: As smart cities grow, an ethical framework becomes more necessary but is currently ignored in favor of focusing on data challenges. However, a smart city involves more than just data gathering; it involves the interactions of residents, businesses, and government with various resources and regulations. This article proposes a sociotechnical view and its mapping to moral foundation theory to provide a comprehensive ethical framework for smart cities.
IEEE INTERNET COMPUTING
(2023)
Article
Computer Science, Software Engineering
Munindar P. Singh, Min Chi, Veena Misra
Summary: We propose a new integrated suite of multimodal sensing and artificial intelligence techniques that incorporate advancements in health psychology to address long-term healthful living. We discuss the challenges and opportunities in realizing this vision.
IEEE INTERNET COMPUTING
(2023)
Article
Chemistry, Multidisciplinary
Kiyofumi Takaba, Saori Maki-Yonekura, Ichiro Inoue, Kensuke Tono, Tasuku Hamaguchi, Keisuke Kawakami, Hisashi Naitow, Tetsuya Ishikawa, Makina Yabashi, Koji Yonekura
Summary: The structure analysis of small crystals is vital in various fields, including synthetic organic chemistry, pharmaceutical and material sciences, where large crystals cannot be obtained. In this study, the structure of an organic molecule, rhodamine6G, was characterized in detail using an X-ray free-electron laser (XFEL) with a resolution of 0.82 A. A direct comparison between the XFEL and electron crystallography methods revealed that both techniques can accurately determine the position of some hydrogen atoms based on the type of chemical bond involved. The variations in distances measured by XFEL and electron diffraction were attributed to the expected differences in X-ray and electron scatterings.
Article
Biochemical Research Methods
Kunio Nakata, Tatsuki Kashiwagi, Naoki Kunishima, Hisashi Naitow, Yoshinori Matsuura, Hiroshi Miyano, Toshimi Mizukoshi, Kensuke Tono, Makina Yabashi, Eriko Nango, So Iwata
Summary: Phosphoketolase and transketolase are important enzymes in the primary metabolism of bifidobacteria. They catalyze the cleavage of xylulose 5-phosphate or fructose 6-phosphate in the first reaction step and have different substrate specificity in the second reaction step. The structures of these enzymes have been determined using crystallography and X-ray free-electron laser.
ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Yoshiaki Kumagai, Weiqing Xu, Kazuki Asa, Toshiyuki Hiraki Nishiyama, Koji Motomura, Shin-ichi Wada, Denys Iablonskyi, Subhendu Mondal, Tetsuya Tachibana, Yuta Ito, Tsukasa Sakai, Kenji Matsunami, Takayuki Umemoto, Christophe Nicolas, Catalin Miron, Tadashi Togashi, Kanade Ogawa, Shigeki Owada, Kensuke Tono, Makina Yabashi, Hironobu Fukuzawa, Kiyonobu Nagaya, Kiyoshi Ueda
Summary: We studied the behavior of nanoplasma generated by the interaction of a hard X-ray pulse with xenon clusters using electron and ion spectroscopy. Through the dependence on XFEL intensity and cluster size, we gained a deep understanding of the formation and disintegration processes of XFEL-ignited nanoplasma. We also tracked the time evolution of plasma electrons within the nanoplasma using a near-infrared probe pulse and observed an unexpected time delay dependence of ion yield enhancement due to NIR pulse heating, indicating an inhomogeneous spatial distribution of plasma electrons.
APPLIED SCIENCES-BASEL
(2023)
Editorial Material
Computer Science, Artificial Intelligence
Michael Pflanzer, Veljko Dubljevic, William A. A. Bauer, Darby Orcutt, George List, Munindar P. P. Singh
Article
Chemistry, Physical
Vivien L. Cherrette, Finn Babbe, Jason K. Cooper, Jin Z. Zhang
Summary: Exciton-phonon interactions are found to cause broadening of photoluminescence line width and slower electron-hole recombination in cubic CsPbBr3 perovskite quantum dots (PQDs) due to structural distortions at room temperature. At low temperature, phonon-assisted recombination is reduced, resulting in minimized line width broadening.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Optics
Yuto Tanaka, Jumpei Yamada, Takato Inoue, Takashi Kimura, Mari Shimura, Yoshiki Kohmura, Makina Yabashi, Tetsuya Ishikawa, Kazuto Yamauchi, Satoshi Matsuyama
Summary: We present a propagation-based phase-contrast imaging method using advanced Kirkpatrick-Baez (AKB) mirrors, which allows high-contrast observations of weak phase objects and correction of field curvature aberrations. By performing experiments at SPring-8, we successfully observed the phase contrast of weak phase objects, such as polystyrene spheres and chemically fixed cells, with high sensitivity (-0.03 rad). Furthermore, we expanded the field of view of the AKB mirrors to the full area of the obtained images (25 x 30 μm) by correcting the field curvature aberration using reconstructed complex wavefields.
Article
Multidisciplinary Sciences
Kenji Tamasaku, Munetaka Taguchi, Ichiro Inoue, Taito Osaka, Yuichi Inubushi, Makina Yabashi, Tetsuya Ishikawa
Summary: X-ray fluorescence spectroscopy is employed to analyze a two-dimensional fluorescence spectrum of copper metal, revealing two-hole satellite features resulting from atomic transitions. The use of nonlinear resonant inelastic X-ray scattering (RIXS) allows for better understanding of the complex electronic structure and the resolution of overlapping spectral features. The results obtained in this study demonstrate that RIXS can open doors for further exploration in the nonlinear regime of fluorescence spectroscopy.
NATURE COMMUNICATIONS
(2023)
Correction
Multidisciplinary Sciences
Kenji Tamasaku, Munetaka Taguchi, Ichiro Inoue, Taito Osaka, Yuichi Inubushi, Makina Yabashi, Tetsuya Ishikawa
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Tomokazu Sano, Tomoki Matsuda, Akio Hirose, Mitsuru Ohata, Tomoyuki Terai, Tomoyuki Kakeshita, Yuichi Inubushi, Takahiro Sato, Kohei Miyanishi, Makina Yabashi, Tadashi Togashi, Kensuke Tono, Osami Sakata, Yoshinori Tange, Kazuto Arakawa, Yusuke Ito, Takuo Okuchi, Tomoko Sato, Toshimori Sekine, Tsutomu Mashimo, Nobuhiko Nakanii, Yusuke Seto, Masaya Shigeta, Takahisa Shobu, Yuji Sano, Tomonao Hosokai, Takeshi Matsuoka, Toshinori Yabuuchi, Kazuo A. Tanaka, Norimasa Ozaki, Ryosuke Kodama
Summary: This study reports the ultrafast lattice behaviour in iron shocked by a femtosecond laser pulse, revealing unique characteristics compared to conventional shock waves. The researchers found that the initial compression state caused by the femtosecond laser-driven shock wave is the same as that caused by conventional shock waves. They also experimentally observed the temporal deviation of peaks of stress and strain waves, as well as the existence of a plastic wave peak between them, which has not been predicted theoretically.
SCIENTIFIC REPORTS
(2023)