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81.
Akasaka T Lu X Kuga H Nikawa H Mizorogi N Slanina Z Tsuchiya T Yoza K Nagase S 《Angewandte Chemie (International ed. in English)》2010,49(50):9715-9719
82.
Yoichi Kamihara Hidenori Hiramatsu Hiroshi Yanagi Hideo Hosono 《Journal of Physics and Chemistry of Solids》2008,69(11):2916-2918
Effects of the replacement of La with Ce on the electronic and magnetic properties of a layered superconductor LaFePO (Tc=∼5 K) were studied. Polycrystalline samples of CeFePO, prepared by a solid-state reaction, showed metallic conduction down to 2 K without exhibiting superconducting transition, although the resistivity decreased largely at temperatures below 30 K. Further, they showed an apparent positive magnetoresistance (MR) below ∼2 K, superposed on a negative MR. Temperature dependence of magnetic susceptibility is decomposed to a temperature-sensitive Curie-Weiss component presumably due to the Ce3+ ions with a magnetic moment of 1.98μB and a less temperature-sensitive component attributable to itinerant electrons. The magnetic interaction between Ce3+ ions and itinerant electrons in CeFePO likely suppresses the superconducting transition observed in LaFePO. 相似文献
83.
Dr. Masahiro Yamamoto Dr. Ryuhei Nakamura Dr. Takafumi Kasaya Dr. Hidenori Kumagai Dr. Katsuhiko Suzuki Dr. Ken Takai 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5819-5822
Deep-sea hydrothermal vents discharge abundant reductive energy into oxidative seawater. Herein, we demonstrated that in situ measurements of redox potentials on the surfaces of active hydrothermal mineral deposits were more negative than the surrounding seawater potential, driving electrical current generation. We also demonstrated that negative potentials in the surface of minerals were widespread in the hydrothermal fields, regardless of the proximity to hydrothermal fluid discharges. Lab experiments verified that the negative potential of the mineral surface was induced by a distant electron transfer from the hydrothermal fluid through the metallic and catalytic properties of minerals. These results indicate that electric current is spontaneously and widely generated in natural mineral deposits in deep-sea hydrothermal fields. Our discovery provides important insights into the microbial communities that are supported by extracellular electron transfer and the prebiotic chemical and metabolic evolution of the ocean hydrothermal systems. 相似文献
84.
Brenden McDearmon Eunhee Lim Kathryn O'Hara Hidenori Nakayama Yingdong Luo Michael L. Chabinyc Craig J. Hawker 《Journal of polymer science. Part A, Polymer chemistry》2017,55(16):2618-2628
A new pentacyclic building block, benzodibenzofuranquinone (BDBFQ), is synthesized in a single step from the inexpensive and readily available feedstocks chloranil and 3‐bromophenol. This versatile repeat unit is incorporated into a series of conjugated materials as either the redox active quinone form or as an electron‐rich dialkylated benzodibenzofuran (BDBF) unit. To illustrate the performance that can be obtained from these systems, optical and electrochemical properties were studied via UV–vis–NIR spectroscopy and cyclic voltammetry. Thin‐film morphology was characterized via grazing incidence wide‐angle X‐ray scattering with thin‐film field‐effect transistor measurements further demonstrating the utility of this system. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2618–2628 相似文献
85.
Hidenori Kimura 《Journal of Optimization Theory and Applications》1971,8(6):431-440
A simple condition which assures the existence of the saddle point is derived for nonlinear differential games of prescribed duration. It is shown that this condition removes the possibility of a kind of singularity which is a source of many troublesome phenomena in differential games. 相似文献
86.
UCST‐type phase transition driven by protein‐derived polypeptide employing gelatin and chitosan 下载免费PDF全文
Here, we describe the thermosensitive reversible phase transition behaviors of polyelectrolyte complex composed of gelatin and chitosan (G/C complex). An aqueous dispersion of the G/C complexes showed a clear upper critical solution temperature (UCST) at around 30°C. The thermosensitive phase transition behavior showed excellent reversibility and large thermal hysteresis as a usual phenomenon based on the intra‐ and inter‐molecular interaction change. A high correlation was observed between the UCST of the G/C complex and the helix‐melting temperature of gelatin by circular dichroism, which suggested that the phase transition of the G/C complex corresponded to the secondary structure (helix‐coil) transition of gelatin. Notably, the UCST of the G/C complex shifted to lower temperatures in the presence of urea, which is well known to destabilize gelatin, whereas the addition of salt led to the dissolution of the G/C complex. It is envisaged that the results of this study will have a significant impact on the fabrication of UCST‐type thermosensitive materials, which can be utilized under aqueous physiological conditions using well‐known biopolymers. This protein‐derived functional material, which responds to the secondary structure transition, could also be used for the development of novel UCST‐type thermosensitive biomaterials. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
87.
Dr. Jun Nakamura Hidenori Yamashiro Hiroto Miya Dr. Kenzo Nishiguchi Dr. Hideki Maki Prof. Dr. Hirokazu Arimoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(36):12104-12112
Vancomycin‐resistant Staphylococcus aureus (S. aureus) (VRSA) uses depsipeptide‐containing modified cell‐wall precursors for the biosynthesis of peptidoglycan. Transglycosylase is responsible for the polymerization of the peptidoglycan, and the penicillin‐binding protein 2 (PBP2) plays a major role in the polymerization among several transglycosylases of wild‐type S. aureus. However, it is unclear whether VRSA processes the depsipeptide‐containing peptidoglycan precursor by using PBP2. Here, we describe the total synthesis of depsi‐lipid I, a cell‐wall precursor of VRSA. By using this chemistry, we prepared a depsi‐lipid II analogue as substrate for a cell‐free transglycosylation system. The reconstituted system revealed that the PBP2 of S. aureus is able to process a depsi‐lipid II intermediate as efficiently as its normal substrate. Moreover, the system was successfully used to demonstrate the difference in the mode of action of the two antibiotics moenomycin and vancomycin. 相似文献
88.
Nitroalkanes have recently been demonstrated to be useful synthetic intermediates for a variety of trans- formations. They have, for example, been converted to carbonyl, la) nitrile oxide,lb) and amino compounds.1c) Especially, 2-aryl-1-nitroalkanes are important in connection with the synthesis of biochemically and pharmacologically interesting compounds. 2) They have also been used as synthetically equivalent to enamines and enolates.3) A widely employed method4) for the synthesis of nitroalkanes involves NaBH4 reduction of conjugated nitroalkenes. The NaBH4 reduction of nitro- alkenes derived from aliphatic aldehydes4b) or ketones5) usually proceeds smoothly in good yields. However, the reduction of 2-aryl-1-nitroalkenes with NaBH4 produces low yields of products due to undesired side reactions such as dimerization.4) 相似文献
89.
Takahiro Kochi Yoki Nakamura Simeng Ma Kazue Hisaoka-Nakashima Dengli Wang Keyue Liu Hidenori Wake Masahiro Nishibori Masahiro Irifune Norimitsu Morioka 《Molecules (Basel, Switzerland)》2021,26(7)
Persistent pain following orofacial surgery is not uncommon. High mobility group box 1 (HMGB1), an alarmin, is released by peripheral immune cells following nerve injury and could be related to pain associated with trigeminal nerve injury. Distal infraorbital nerve chronic constriction injury (dIoN-CCI) evokes pain-related behaviors including increased facial grooming and hyper-responsiveness to acetone (cutaneous cooling) after dIoN-CCI surgery in mice. In addition, dIoN-CCI mice developed conditioned place preference to mirogabalin, suggesting increased neuropathic pain-related aversion. Treatment of the infraorbital nerve with neutralizing antibody HMGB1 (anti-HMGB1 nAb) before dIoN-CCI prevented both facial grooming and hyper-responsiveness to cooling. Pretreatment with anti-HMGB1 nAb also blocked immune cell activation associated with trigeminal nerve injury including the accumulation of macrophage around the injured IoN and increased microglia activation in the ipsilateral spinal trigeminal nucleus caudalis. The current findings demonstrated that blocking of HMGB1 prior to nerve injury prevents the onset of pain-related behaviors, possibly through blocking the activation of immune cells associated with the nerve injury, both within the CNS and on peripheral nerves. The current findings further suggest that blocking HMGB1 before tissue injury could be a novel strategy to prevent the induction of chronic pain following orofacial surgeries. 相似文献
90.
Mizuno H Sakurai H Amaya T Hirao T 《Chemical communications (Cambridge, England)》2006,(48):5042-5044
Oxidative ligand coupling of organoborates was catalyzed by VO(OEt)Cl(2) under oxygen atmosphere, which provides a versatile method for the selective synthesis of symmetrical or unsymmetrical biaryls. 相似文献