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941.
Suenaga M Kaneko Y Kadokawa J Nishikawa T Mori H Tabata M 《Macromolecular bioscience》2006,6(12):1009-1018
An amphiphilic poly(N-propargylamide) with galactose and lauryloyl groups was synthesized by copolymerization of the corresponding N-propargylamide monomers using a Rh catalyst. The obtained copolymer formed a one-handed helical conformation and molecular aggregates in water. The observations by fluorescence microscopy in a cell culture experiment in the presence of dye-labeled copolymer indicated that the copolymer was incorporated into the cells. 相似文献
942.
943.
Katsufumi Tanaka Takanobu Hira Ryuichi Fukui Nozomi Nakagawa Ryuichi Akiyama Masami Nakano Keisuke Yoshida Teppei Tsujita 《Colloid and polymer science》2011,289(7):855-862
An attempt has been made to develop a candidate for electro-rheological (ER) nano-suspensions based on anatase titanium dioxide
with a particle diameter around 300 nm. The micro-gap flow behavior and microstructure were evaluated for a suspension with
a particle volume fraction of 8.8 vol.%. The ER effect was investigated for the nano-suspension. The effect of shearing time
on the ER responses was also investigated. The ER effect was discussed in comparison to the effect previously reported for
the nano-suspension based on rutile titanium dioxide with a particle diameter around 15 nm. 相似文献
944.
Keisuke Hatada Kuniko Hayakawa Fabrizio Palumbo Augusto Marcelli 《Journal of synchrotron radiation》2016,23(2):560-565
The occurrence of scissors modes in crystals that have deformed ions in their unit cells was predicted some time ago. The theoretical value of their energy is rather uncertain, however, ranging between ten and a few tens of eV, with the corresponding widths of 10?7 to 10?6 eV. Their observation by resonance fluorescence experiments therefore requires a photon spectrometer covering a wide energy range with a very high resolving power. Here, a new experiment is proposed and discussed in which such difficulties are overcome by measuring with a superconducting quantum interference device (SQUID) the variation of the magnetic field associated with the excitation of scissors modes. 相似文献
945.
Shinji Nishikawa Sayaka Kami Nurul Ashikin Badrul Haswan Takahiro Uno Takahito Itoh Masataka Kubo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(5):622-628
Polyfluorenes with pendant allyl groups were prepared by terpolymerization of 9,9‐dihexylfluorene‐2,7‐bis(trimethyleneborate), 2,7‐dibromo‐9,9‐bis(2‐allyloxyethyl)fluorene, and 4,7‐dibromo‐2,1,3‐benzothiazole, or 4,7‐dibromo‐2,1,3‐naphthoselenadiazole using Suzuki coupling reaction. The subsequent hydrosilylation reaction of these precursor polymers with ethoxydimethylsilane quantitatively converted the allyl groups to ethoxysilyl groups. Hybridization of the emitting polyfluorenes with silicone was successfully achieved by the solvent‐free sol–gel reaction of tetraethoxysilane and silanol‐terminated polydimethylsiloxane in the presence of the ethoxysilyl‐functionalized polyfluorenes. Fluorescence spectra of these luminescent silicones revealed that emitting polyfluorenes were dispersed homogeneously in the matrix of silicone without aggregation. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 622–628 相似文献
946.
Of the previously reported Horner-Wadsworth-Emmons (HWE) reaction, the olefination of methyl bis(2,4-difluorophenyl)phosphonoacetate (la) with various aldehydes gave unsaturated esters in the highest cis-selectivity. 相似文献
947.
948.
Keisuke Okumura Kazuma Mase Dr. Nobuhiro Yanai Prof. Dr. Nobuo Kimizuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7721-7726
A new family of surface‐functionalized CdSe/ZnS core‐shell quantum dots (csQD) has been developed, which work as triplet sensitizers for triplet‐triplet annihilation‐based photon upconversion (TTA‐UC). The surface modification of csQD with acceptor molecules plays a key role in the efficient relay of the excited energy of csQD to emitter molecules in the bulk solution, where the generated emitter triplets undergo triplet‐triplet annihilation that leads to photon upconversion. Interestingly, improved UC properties were achieved with the core‐shell QDs compared with core‐only CdSe QDs (cQD). The threshold excitation intensity, which is defined as the necessary irradiance to achieve efficient TTA process, decreases by more than a factor of four. Furthermore, the total UC quantum yield is enhanced more than 50‐fold. These enhancements should be derived from better optical properties of csQD, in which the non‐radiative surface recombination sites are passivated by the shell layer with wider bandgap. 相似文献
949.
Cover Picture: Sequential SNAr Reaction/Suzuki–Miyaura Coupling/C−H Direct Arylations Approach for the Rapid Synthesis of Tetraaryl‐Substituted Pyrazoles (Chem. Asian J. 8/2015) 下载免费PDF全文
950.
Fragmentation patterns of methyloxime‐trimethylsilyl derivatives of constitutive mono‐ and disaccharide isomers analyzed by gas chromatography/field ionization mass spectrometry 下载免费PDF全文