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1.
Nishimura N Tanikawa J Fujii M Kawahara T Ino J Akita T Fujino T Tada H 《Chemical communications (Cambridge, England)》2008,(30):3564-3566
MnO(2) nanoparticle-loaded TiO(2) prepared by a green process capable of removing harmful MnO(4)(-) ions from water exhibits catalytic activity for a test reaction, H(2)O(2) decomposition, in the dark with its activity enhanced by UV light irradiation. 相似文献
2.
Hideyuki Kawahara Yoshihiro Ueno Nanae Abe Shiho Kishino Kazuhiro Ema Masahiro Rikukawa Yuko Tabuchi Naoya Ogata 《Optical Review》1997,4(1):188-190
We measured the third-order optical nonlinearity of regioregular head-to-tail coupled poly (3-hexylthiophene) (HT-PHT) and regiorandom poly (3-hexylthiophene) (R-PHT) around exciton resonance using degenerate four wave mixing. The observed value of ∣χ(3)∣ at the exciton resonance peak of HT-PHT is in the order of 10-9 esu which is approximately three-fold larger than that of R-PHT. We observed for the first time the enhancement in optical nonlinearity that occurs through the control of regularity of the polymeric structure. Response time of the nonlinearity was also measured using the transient grating method. The decay time of the transient grating in R-PHT and HT-PHT was less than 2 ps. 相似文献
3.
Yuji Koga Nanae Yoshida Kouki Matsubara 《Journal of polymer science. Part A, Polymer chemistry》2009,47(17):4366-4378
We successfully developed phosphorescent cyclometallated iridium‐containing metallopolymers, which are near‐red luminescent iridium complexes bearing phosphine‐containing copolymers used as polymer ligands, and investigated their photoluminescence and electroluminescence behavior. The phosphine copolymer ligand made from methyl methacrylate and 4‐styryldiphenylphosphine can be used as an anchor, which coordinates luminescent iridium units to form the metallopolymer easily. Organic light‐emitting diodes were fabricated from the metallopolymer and its nonpolymer analog, [IrCl(piq)2PPh3]. These complexes exhibited quite similar luminescence behavior, except for emission from the free‐phosphine‐units in the polymer side chain and their energy‐transferring properties from host to guest materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4366–4378, 2009 相似文献
4.
Li D Ikeda T Matsuoka N Nohara T Zhang H Sakamoto T Nonaka G 《Chemical & pharmaceutical bulletin》2006,54(10):1425-1428
From the unripe fruits of Lo Han Kuo (Siraitia grosvenori), a Chinese medicinal plant, two new cucurbitane triterpene glycosides, 20-hydroxy-11-oxomogroside IA(1) (1) and 11-oxomogroside IIE (2), were isolated along with five known cucurbitane glycosides, 11-oxomogroside IA(1) (3), mogroside IIE (4), mogroside III (5), mogroside IVA (6), and mogroside V (7), and two flavonoid glycosides, kaempferol 7-O-alpha-L-rhamnopyranoside (8) and kaempferol 3,7-di-O-alpha-L-rhamnopyranoside (9). Their structures were determined on the basis of detailed analyses of 1D, 2D-NMR spectroscopic methods and by comparing with literature values. This paper describes the first investigation of unripe bitter Lo Han Kuo fruits. 相似文献
5.
Shuping Wang Nanae Shibahara Daishi Kuramashi Shinpei Okawa Naoto Kakuta Eiji Okada Atsushi Maki Yukio Yamada 《Optical Review》2010,17(4):410-420
In order to investigate the effects of anatomical variation in human heads on the optical mapping of brain activity, we perform
simulations of optical mapping by solving the photon diffusion equation for layered-models simulating human heads using the
finite element method (FEM). Particularly, the effects of the spatial variations in the thicknesses of the skull and cerebrospinal
fluid (CSF) layers on mapping images are investigated. Mapping images of single active regions in the gray matter layer are
affected by the spatial variations in the skull and CSF layer thicknesses, although the effects are smaller than those of
the positions of the active region relative to the data points. The increase in the skull thickness decreases the sensitivity
of the images to active regions, while the increase in the CSF layer thickness increases the sensitivity in general. The images
of multiple active regions are also influenced by their positions relative to the data points and by their depths from the
skin surface. 相似文献
6.
Usuki T Yasuda N Yoshizawa-Fujita M Rikukawa M 《Chemical communications (Cambridge, England)》2011,47(38):10560-10562
Shikimic acid, the starting material in the commercial synthesis of oseltamivir phosphate (Tamiflu?), was efficiently extracted and isolated from Ginkgo biloba leaves utilizing the ionic liquid 1-butyl-3-methylimidazolium chloride ([bmim]Cl), which dissolves cellulose. 相似文献
7.
Yoshihisa Kurasawa Akiko Tsuruoka Nanae Rikiishi Noriko Fujiwara Yoshihisa Okamoto Ho Sik Kim 《Journal of heterocyclic chemistry》2000,37(4):791-798
The reaction of the alkylhydrazinoquinoxaline N‐oxides 2a‐d with dimethyl acetylenedicarboxylate gave the dimethyl 1‐alkyl‐1,5‐dihydropyridazino[3,4‐b]qumoxaline‐3,4‐dicarboxylates 3a‐d , whose reaction with nitrous acid effected the C4‐oxidation to afford the dimethyl 1‐alkyl‐4‐hydroxy‐1,4‐dihydropyridazino‐[3,4‐b]quinoxaline‐3,4‐dicarboxylates 4a‐d , respectively. The reaction of compounds 4a‐d with 1,8‐diazabicyclo[5.4.0]‐7‐undecene in ethanol provided the ethyl 1‐alkyl‐4‐oxo‐1,4‐dihydropyridazino[3,4‐b]quinoxa‐line‐3‐carboxylates 5a‐d , while the reaction of compounds 4a‐d with potassium hydroxide furnished the 1‐alkyl‐4‐oxo‐1,4‐dihydropyridazino[3,4‐b]quinoxaline‐3‐carboxylic acids 6a‐d , respectively. Compounds 6c,d were also obtained by the reaction of compounds 5c,d with potassium hydroxide, respectively. 相似文献
8.
Yu Kitamura Emi Terado Zechen Zhang Prof. Hirofumi Yoshikawa Dr. Tomoko Inose Prof. Hiroshi Uji-i Prof. Masaharu Tanimizu Prof. Akihiro Inokuchi Dr. Yoshinobu Kamakura Prof. Daisuke Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16347-16353
Novel metal–organic frameworks containing lanthanide double-layer-based secondary building units (KGF-3) were synthesized by using machine learning (ML). Isolating pure KGF-3 was challenging, and the synthesis was not reproducible because impurity phases were frequently obtained under the same synthetic conditions. Thus, dominant factors for the synthesis of KGF-3 were identified, and its synthetic conditions were optimized by using two ML techniques. Cluster analysis was used to classify the obtained powder X-ray diffractometry patterns of the products and thus automatically determine whether the experiments were successful. Decision-tree analysis was used to visualize the experimental results, after extracting factors that mainly affected the synthetic reproducibility. Water-adsorption isotherms revealed that KGF-3 possesses unique hydrophilic pores. Impedance measurements demonstrated good proton conductivities (σ=5.2×10−4 S cm−1 for KGF-3(Y)) at a high temperature (363 K) and relative humidity of 95 % RH. 相似文献
9.
Naofumi Naga Yoshikazu Ohkura Nanae Tagaya Haruhiko Tomoda 《Journal of polymer science. Part A, Polymer chemistry》2011,49(23):4935-4940
Alternating copolymerization of 9,9‐bis(3,6,9‐trioxadecyl)‐2,7‐dibromofluorene (ODFl) or 9,9‐bis(3,6‐dioxaheptyl)‐2,7‐dibromofluorene with Si containing divinyl compounds, divinyldiphenylsilane (VPS), or divinyldimethylsilane (VMS) is investigated using the Mizoroki–Heck reaction with palladium(II) acetate. The corresponding alternating copolymer is obtained in the copolymerization of ODFl with VPS. The copolymerization of ODFl with VMS yields low molecular weight oligomers. Optical properties of the ODFl–VPS copolymer have been investigated with UV–vis absorption and photoluminescence (PL) spectroscopy. The ODFl–VPS copolymer shows absorption peaks due to π–π* transition and intramolecular charge transfer through σ–π moiety at around 330 and 360–400 nm, respectively. An emission peak is observed at 450 nm in the PL spectrum of the ODFl–VPS copolymer, and the PL quantum yield is 0.19. The PL spectroscopy of ODFl–VPS copolymer is investigated in the presence of Li+, Na+, and K+, and the intensity of emission peak is decreased by those metal cations, especially by Na+. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011. 相似文献
10.
Yuji Tokunaga Nanae Wakamatsu Koichiro Akasaka Kenji Hisada Youji Shimomura 《Tetrahedron letters》2006,47(16):2679-2682
By using high-pressure conditions the formation of pseudorotaxane via the slipping approach is accelerated. Analysis of the effects of pressure on the rate constants affords activation volumes for the pseudorotaxane forming slipping reactions. 相似文献