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421.
Mizoguchi H Matsuishi S Hirano M Tachibana M Takayama-Muromachi E Kawaji H Hosono H 《Physical review letters》2011,106(5):057002
We found that the ZrCuSiAs-type crystal CeNi(0.8)Bi(2) with a layered structure composed of alternate stacking of [CeNi(x)Bi(1)](δ+) and Bi(2)(δ-) exhibits a superconductive transition at ~4 K. The conductivities, magnetic susceptibilities, and heat capacities measurements indicate the presence of two types of carriers with notable different masses, i.e., a light electron responsible for superconductivity and a heavy electron interacting with the Ce 4f electron. This observation suggests that 6p electrons of Bi(2) forming the square net and electrons in CeNi(x)Bi(1) layers primarily correspond to the light and heavy electrons, respectively. 相似文献
422.
Kimata M Terashima T Kurita N Satsukawa H Harada A Kodama K Takehana K Imanaka Y Takamasu T Kihou K Lee CH Kito H Eisaki H Iyo A Fukazawa H Kohori Y Harima H Uji S 《Physical review letters》2011,107(16):166402
Cyclotron resonance (CR) measurements for the Fe-based superconductor KFe(2)As(2) are performed. One signal for CR is observed, and is attributed to the two-dimensional α Fermi surface at the Γ point. We found a large discrepancy in the effective masses of CR [(3.4±0.05)m(e) (m(e) is the free-electron mass)] and de Haas-van Alphen results, a direct evidence of mass enhancement due to electronic correlation. A comparison of the CR and de Haas-van Alphen results shows that both intra- and interband electronic correlations contribute to the mass enhancement in KFe(2)As(2). 相似文献
423.
Fukushima H Hiratate A Takahashi M Saito-Hori M Munetomo E Kitano K Saito H Takaoka Y Yamamoto K 《Chemical & pharmaceutical bulletin》2008,56(8):1110-1117
Dipeptidyl peptidase IV (DPP-IV) inhibitors have attracted attention as potential drugs for use in the treatment of type 2 diabetes because they prevent the degradation of glucagon-like peptide-1 (GLP-1) and extend its duration of action. We previously reported that 2-cyano-4-fluoropyrrolidines act as potent DPP-IV inhibitors and have been modifying the 1-position of pyrrolidine to obtain more useful inhibitors. An L-tert-butylglycine derivative was found to be a stable and potent DPP-IV inhibitor that exhibits a glucose lowering effect in vivo. Here, we report the synthesis of and biological data on the aforementioned derivatives. 相似文献
424.
Dr. Daisuke Asakura Dr. Eiji Hosono Dr. Miho Kitamura Dr. Koji Horiba Dr. Eisuke Magome Dr. Hiroyuki Setoyama Dr. Eiichi Kobayashi Dr. Hayato Yuzawa Dr. Takuji Ohigashi Dr. Takaaki Sakai Dr. Ryoichi Kanega Dr. Takashi Funaki Dr. Yukari Sato Dr. Akihiro Ohira 《化学:亚洲杂志》2023,18(1):e202201047
We performed X-ray absorption studies for the electrolytes of a Ti−Mn redox flow battery (RFB) to understand the redox reaction of the Ti/Mn ions and formation of precipitates in charged catholyte, because suppression of the disproportionation reaction is a key to improve the cyclability of Ti−Mn RFB and enhance the energy density. Hard X-ray absorption spectroscopy with a high transmittance and soft X-ray absorption spectroscopy to directly observe the 3d orbitals were complementarily employed. Moreover, the Ti/Mn 3d electronic structure for each precipitate and solution in the charged catholyte was investigated by using scanning transmission X-ray microscopy: the valence of Mn in the precipitate is mostly attributed to 4+, and the solution includes only Mn2+. This charge disproportionation reaction should occur after the Mn ions in the catholyte should be oxidized from Mn2+ to Mn3+ by charge. 相似文献
425.
Extremal Problems for Mappings with Generalized Parametric Representation in $${{\mathbb {C}}}^{n}$$
Hidetaka Hamada Mihai Iancu Gabriela Kohr 《Complex Analysis and Operator Theory》2016,10(5):1045-1080
In this paper we are concerned with the family \(\widetilde{S}^t_A(\mathbb {B}^n)\) (\(t\ge 0\)) of normalized biholomorphic mappings on the Euclidean unit ball \(\mathbb {B}^n\) in \({\mathbb {C}}^n\) that can be embedded in normal Loewner chains whose normalizations are given by time-dependent operators \(A\in \widetilde{\mathcal {A}}\), where \(\widetilde{\mathcal {A}}\) is a family of measurable mappings from \([0,\infty )\) into \(L({\mathbb {C}}^n)\) which satisfy certain natural assumptions. In particular, we consider extreme points and support points associated with the compact family \(\widetilde{S}^t_A(\mathbb {B}^n)\), where \(A\in \widetilde{\mathcal {A}}\). We prove that if \(f(z,t)=V(t)^{-1}z+\cdots \) is a normal Loewner chain such that \(V(s)f(\cdot ,s)\in \mathrm{ex}\,\widetilde{S}^s_A(\mathbb {B}^n)\) (resp. \(V(s)f(\cdot ,s)\in \mathrm{supp}\,\widetilde{S}^s_A(\mathbb {B}^n)\)), then \(V(t)f(\cdot ,t)\in \mathrm{ex}\, \widetilde{S}^t_A(\mathbb {B}^n)\), for all \(t\ge s\) (resp. \(V(t)f(\cdot ,t)\in \mathrm{supp}\,\widetilde{S}^t_A(\mathbb {B}^n)\), for all \(t\ge s\)), where V(t) is the unique solution on \([0,\infty )\) of the initial value problem: \(\frac{d V}{d t}(t)=-A(t)V(t)\), a.e. \(t\ge 0\), \(V(0)=I_n\). Also, we obtain an example of a bounded support point for the family \(\widetilde{S}_A^t(\mathbb {B}^2)\), where \(A\in \widetilde{\mathcal {A}}\) is a certain time-dependent operator. We also consider the notion of a reachable family with respect to time-dependent linear operators \(A\in \widetilde{\mathcal {A}}\), and obtain characterizations of extreme/support points associated with these families of bounded biholomorphic mappings on \(\mathbb {B}^n\). Useful examples and applications yield that the study of the family \(\widetilde{S}^t_A(\mathbb {B}^n)\) for time-dependent operators \(A\in \widetilde{\mathcal {A}}\) is basically different from that in the case of constant time-dependent linear operators. 相似文献
426.
Kiyoshi Suzuki Yuko Nishimura Yuta Kanematsu Yoshie Masuda Shuzaemon Satoh Hidetaka Tobita 《大分子反应工程》2012,6(1):17-23
To understand if either of two controversial models for the retardation by RAFT agents is applicable, styrene polymerization using dithiobenzoate as the RAFT agent is carried out in both bulk and miniemulsion systems with the same rates of radical generation and the same RAFT agent concentrations. Miniemulsion polymerization with average diameters of the miniemulsion droplets of ≈107 nm is by far faster than in bulk, and the obtained rate of polymerization agrees well with the calculated results assuming a bimolecular termination between propagating radical and intermediate radical, generated by the addition reaction of propagating radical to the RAFT agent, which shows that the intermediate termination is the major reason for rate retardation by the RAFT agent.
427.
Kajihara K Hirano M Skuja L Hosono H 《Journal of the American Chemical Society》2006,128(16):5371-5374
A procedure to produce stable hydroperoxy radicals (HO*2) in bulk amorphous SiO(2) (a-SiO(2)) has been developed. Oxygen molecules incorporated in the interstitial voids in a-SiO(2) react with mobile hydrogen atoms (H(0)) generated by the photolysis of silanol (SiOH) groups with F(2)-laser light (lambda = 157 nm, hnu = 7.9 eV), resulting in the efficient creation of interstitial HO*2. The high yield of HO*2 suggests that the collisions of the reaction intermediate with the void wall play an important role in dissipating the excess energy of the intermediate instead of the triple collision observed in the gas phase reaction. The resultant HO*2 is thermally stable up to 100 degrees C. 相似文献
428.
Kamihara Y Hiramatsu H Hirano M Kawamura R Yanagi H Kamiya T Hosono H 《Journal of the American Chemical Society》2006,128(31):10012-10013
We report superconductivity in an iron-based layered oxy-pnictide LaOFeP. LaOFeP is composed of an alternate stack of lanthanum oxide (La3+O2-) and iron pnictide (Fe2+P3-) layers. Magnetic and electrical resistivity measurements verify the occurrence of the superconducting transition at approximately 4 K. 相似文献
429.
Hidetaka Noritomi Naohiro Igari Kenji Kagitani Yoshihiro Umezawa Yasutaka Muratsubaki Satoru Kato 《Colloid and polymer science》2010,288(8):887-891
Silver nanoparticles were prepared in reverse micelles of sucrose fatty acid esters. The TEM image showed that the obtained
silver nanoparticles displayed a wide variety of shapes. The size of silver nanoparticles was strongly dependent upon a kind
of reducing agents and tended to increase with an increase in reaction temperature. Moreover, the size of silver nanoparticles
was controlled by using sucrose fatty acids at a different esterification degree or by mixing sucrose fatty acid monoesters
with polyoxyethylene sorbitan fatty acid monoesters. The resultant silver colloid could be preserved for at least 1 month
without precipitation. 相似文献
430.
Koji Fushimi Dr. Shunsuke Yamamoto Hidetaka Konno Dr. Hiroki Habazaki Dr. 《Chemphyschem》2009,10(2):420-426
To the limit : Electrolyte flow accelerates the mass‐transfer process in a droplet cell (see picture). The limiting current in the cell is expressed as a sum of hydrodynamic and stagnant terms. The current derived from the latter term indicates that convective mass transfer in the cell would be changed dramatically at a significantly small volumetric flow rate.