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81.
Noriyuki Kida Masanori Hikita Izuru Kashima Masaya Enomoto Miho Itoi Norimichi Kojima 《Polyhedron》2009,28(9-10):1694-1697
A photo-sensitive organic–inorganic hybrid system (SP)[FeIIFeIII(dto)3] (SP = spiropyran, dto = C2O2S2), has recently been developed, where the photo-isomerization of the intercalated spiropyran in solid state triggers the change of the magnetic properties, including the ferromagnetic transition temperature from 5 to 22 K. We performed 57Fe Mössbauer measurement in order to probe the microscopic states of iron ions in (SP)[FeIIFeIII(dto)3] and have investigated the photo-induced effect on them. The sample without UV-irradiation shows the charge transfer phase transition between 200 and 70 K and the higher and lower temperature phases coexist below 70 K, whereas the UV-irradiated sample does not undergo the charge transfer phase transition and the higher temperature phase is stable between 200 and 6 K. 相似文献
82.
Taku Hirama Takayuki Umemura Noriyuki Kogure Mariko Kitajima Hiromitsu Takayama 《Tetrahedron letters》2017,58(3):223-226
A new procedure for the asymmetric total synthesis of lythraceous alkaloids with a 4-arylquinolizidine skeleton was developed, which involved an organocatalyzed asymmetric intramolecular aza-Michael addition. 相似文献
83.
Dr. Hideya Kawasaki Teruyuki Yao Takashi Suganuma Kouji Okumura Dr. Yuichi Iwaki Prof. Tetsu Yonezawa Tatsuya Kikuchi Prof. Ryuichi Arakawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(35):10832-10843
We report a new and facile method for synthesizing 3D platinum nanoflowers (Pt Nfs) on a scratched silicon substrate by electroless galvanic displacement and discuss the applications of the Pt Nfs in surface‐assisted laser desorption/ionization‐mass spectrometry (SALDI‐MS). Surface scratching of n‐type silicon is essential to induce Pt Nf growth on a silicon substrate (to obtain a Pt Nf silicon hybrid plate) by the galvanic displacement reaction. The Pt Nf silicon hybrid plate showed excellent SALDI activity in terms of the efficient generation of protonated molecular ions in the absence of a citrate buffer. We propose that the acidity of the Si? OH moieties on silicon increases because of the electron‐withdrawing nature of the Pt Nfs; hence, proton transfer from the Si? OH groups to the analyte molecules is enhanced, and finally, thermal desorption of the analyte ions from the surface occurs. Signal enhancement was observed for protonated molecular ions produced from a titania nanotube array (TNA) substrate on which Pt nanoparticles had been photochemically deposited. Moreover, surface modification of the Pt Nf silicon hybrid plate by perfluorodecyltrichlorosilane (FDTS) (to obtain an FDTS‐Pt Nf silicon hybrid plate) was found to facilitate soft SALDI of labile compounds. More interestingly, the FDTS‐Pt Nf silicon hybrid plate acts 1) as a high‐affinity substrate for phosphopeptides and 2) as a SALDI substrate. The feasibility of using the FDTS‐Pt Nf silicon hybrid plate for SALDI‐MS has been demonstrated by using a β‐casein digest and various analytes, including small molecules, peptides, phosphopeptides, phospholipids, carbohydrates, and synthetic polymers. The hybridization of Pt Nfs with a scratched silicon substrate has been found to be important for achieving excellent SALDI activity. 相似文献
84.
F. Yonezawa 《Solid State Communications》1980,35(11):823-828
The self-energy to define the ensemble average of a one-electron Green function for a disordered system is related to the vertex correction for the average of the product of two Green functions by the generalized optical theorem or by the so-called Ward identity. Using this relationship, we evaluate the conductivity of liquid metals both by the Ishida-Yomezawa approximation and by the effective medium approximation from the self-energy forms corresponding to respective approximations. The conductivity formulations thus obtained are shown to be identical with those derived from the diagram method. 相似文献
85.
Crosslinked PTFE (XF) samples were fluorinated at 293-593 K under 0.7-101 kPa F2 and for 1 h to 7 days to improve its thermal stability. Because the weight uptake which may be caused by the fluorine addition was detected at room temperature, CC bonds in XF can be fluorinated and the fluorine content was saturated after 72 h. Weights of all samples increased more than that of original XF through additional fluorination of CC bonds, whereas it decreased by the chain-scission to form gaseous fluorocarbons such as CF4. The intensity ratio in IR spectra of the peaks correspond to the double bond (CFCF2) at 1785 cm−1 and the characteristic peaks of PTFE at 1794 cm−1, IPTFE/IPTFE was smaller for the fluorinated XF rather than that for XF. Average values of heat of crystallization (ΔHc) for all fluorinated XF samples were about 2 J/g higher than that of the original XF. The decomposition temperature calculated from the TG curves increased with increasing reaction temperature and reaction time up to 72 h. Thermal stability of XF was improved through fluorine gas treatment. 相似文献
86.
Noriyuki Otsubo 《Journal of Number Theory》2011,131(4):648-660
We compare two calculations due to Bloch and the author of the regulator of an elliptic curve with complex multiplication which is a quotient of a Fermat curve, and express the special value of its L-function at s=0 in terms of special values of generalized hypergeometric functions. 相似文献
87.
Suzuki N Aihara N Takahara H Watanabe T Iwasaki M Saburi M Hashizume D Chihara T 《Journal of the American Chemical Society》2004,126(1):60-61
Five-membered metallacyclic alkynes that have no substituents adjacent to the triple bond have been synthesized, isolated, and structurally characterized. Zirconocene dichlorides, Cp'2ZrCl2 (Cp' = C5H5, C5H4-t-Bu), reacted with 1,4-dichlorobut-2-yne in the presence of magnesium to give 1-zirconacyclopent-3-yne compounds (5 (a) Cp' = C5H5, (b) Cp' = C5H4-t-Bu) that have a -CH2CCCH2- moiety in good yields. They are stable enough to be isolated in a pure form, despite the absence of substituents. 5a reacted with an equimolar amount of Cp2Zr(but-1-ene)(PMe3) to produce a bimetallic complex in which the zirconacyclopentyne coordinates to the other zirconocene moiety as an alkyne. 相似文献
88.
We experimentally demonstrate continuous-variable quantum teleportation beyond the no-cloning limit. We teleport a coherent state and achieve the fidelity of 0.70 +/- 0.02 that surpasses the no-cloning limit of 2/3. Surpassing the limit is necessary to transfer the nonclassicality of an input quantum state. By using our high-fidelity teleporter, we demonstrate entanglement swapping, namely, teleportation of quantum entanglement, as an example of transfer of nonclassicality. 相似文献
89.
Takayuki MaruyamaYasuyuki Fujie Noriyuki OyaEisuke Hosaka Aki KanazawaDaisuke Tanaka Yoshiyuki HattoriJiro Motoyoshiya 《Tetrahedron》2011,67(36):6927-6933
The control of peroxyoxalate chemiluminescence (PO-CL) by the coordination of nitrogen-containing ligands and metal cations was investigated. Turning the CL off and on was done by PO-CL using 15-monoazacrown-5-tethered anthracene and alkali metal ions. CL quenching and regeneration was also observed in the separated molecular system of 15-monoazacrown-5 and the fluorophores. CL quenching by a number of ligands bearing dipicolylamino groups was evaluated by these PO-CL reactions and found to be closely related to their oxidation potentials, which is dependent on the Weller rate law for electron exchange and this provides strong support for the existence of the CIEEL PO-CL process. When Zn2+ or Cu2+ are added to the PO-CL system quenched by the ligand, N-[2-(2,2′-dipicolylamino)ethyl]aniline, CL was turned on because the electron donating ability of the ligands was modulated. This was controlled by the coordination of the studied metal ions and, therefore, this system results in CL because of host-guest interactions. 相似文献
90.
Masaya Enomoto Noriyuki KidaNorimichi Kojima Isao WatanabeTakao Suzuki Yasuyuki Ishii 《Polyhedron》2011,30(18):3137-3139
We have investigated the magnetic properties of iron mixed-valence complexes, (n-CnH2n+1)4N[FeIIFeIII(dto)3] (dto = C2O2S2, n = 3, 5), in which not only a ferromagnetic transition but also a novel charge transfer phase transition (CTPT) take place [1]. This CTPT can be observed under ambient pressure for n = 3, while it appears abruptly above 0.5 GPa for n = 5 [2]. Recently, we have measured the muon spin relaxation (μSR) for the CTPT of n = 3, which revealed the dynamical process of electron-transfer between FeII and FeIII and its frequency was estimated at about 0.1 MHz [3]. To investigate the pressure induced CTPT for n = 5, we carried out the μSR measurement for n = 5 at 150 K between 0.30 and 0.64 GPa with the 4He gas-operated pressure system. The asymmetry of the muon spin relaxation for n = 5 with Cu-Be pressure cell was almost constant up to 0.55 GPa, while it rapidly decreased with increasing pressure above 0.60 GPa. This result shows that the applied pressure causes the spin fluctuation due to the CTPT, which induces the decrease of the asymmetry of muon spin relaxation. This experiment can correctly decide the phase transition pressure from the absence to the appearance of the CTPT for n = 5. 相似文献