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991.
Mitsuru Sugimoto 《Journal of Functional Analysis》2007,248(1):79-106
We consider the dilation property of the modulation spaces Mp,q. Let be the dilation operator, and we consider the behavior of the operator norm ‖Dλ‖Mp,q→Mp,q with respect to λ. Our result determines the best order for it, and as an application, we establish the optimality of the inclusion relation between the modulation spaces and Besov spaces, which was proved by Toft [J. Toft, Continuity properties for modulation spaces, with applications to pseudo-differential calculus, I, J. Funct. Anal. 207 (2004) 399-429]. 相似文献
992.
Wurster’s Blue‐type Cation Radicals Framed in a 5,10‐Dihydrobenzo[a]indolo[2,3‐c]carbazole (BIC) Skeleton: Dual Electrochromism with Drastic Changes in UV/Vis/NIR and Fluorescence
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Prof. Takanori Suzuki Yuto Sakano Yusuke Tokimizu Dr. Youhei Miura Dr. Ryo Katoono Prof. Kenshu Fujiwara Prof. Naoki Yoshioka Prof. Nobutaka Fujii Prof. Hiroaki Ohno 《化学:亚洲杂志》2014,9(7):1841-1846
Electron‐donating dihydrobenzindolocarbazoles (BICs) 1 a – c , which adopt planar disk‐shaped geometries, were prepared by gold(I)‐catalyzed cyclization as a key step. Due to the presence of a 1,4‐phenylenediamine (PD) moiety in the framework, they undergo reversible one‐electron oxidation to the corresponding Wurster’s Blue (WB)‐type species that exhibits NIR absorptions up to λ=1200 nm. In the case of the N,N′‐dimethyl derivative, cation radical 1 c +. is stable enough to be isolated as a salt and X‐ray analysis indicated paraquinoid‐type bond alternation in the WB core unit, whereas the bond lengths in the peripheral benzene rings are identical to those in the neutral donor. Upon electrochemical interconversion, the redox pairs of 1 a – c and 1 a – c +. exhibited an electrochromic response in the UV/Vis/NIR region, which was accompanied by a drastic change in the fluorescence spectrum because only neutral donors 1 a – c are highly emissive (ΦF: 0.7–0.8). 相似文献
993.
Akihiro Fujii Toshihiro Koura Takashi Yoshimoto Toshiyuki Kawabata Yoshinori Nakamura Keita Hamamichi Hitoshi Kakimoto Yoshimune Yamada Mitsuo Yoshioka Masayoshi Yamamoto Kazuichi Hayakawa 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(2):707-717
A variety of wild mushrooms were collected in a forest on the Noto Peninsula, Japan, to determine the concentration of 137Cs and 40K. The wild mushroom species belong to the orders Agaricales and Aphyllophorales. The concentration of 137Cs varied widely (1.4–4,100 Bq/kg dry weight) in mushrooms growing in soil. On the contrary, 137Cs concentration levels were relatively low (1.9–20 Bq/kg-dry weight) in mushrooms growing on wood. The concentration of 40K varied widely (12–2,400 Bq/kg-dry weight) in contrast with several previous reports that suggest relatively constant 40K levels in mushrooms. Unusually low concentrations of 40K were observed in a few mushroom species that had very hard fruiting bodies with peculiar shapes. The mean and median of 137Cs concentration in the present study were similar to those previously reported for Japanese mushrooms. Among the Agaricales mushrooms, Entolomataceae and Tricholomataceae families growing in soil had the highest concentration of 137Cs. Among the Aphyllophorales mushrooms, Gomphaceae and Ramariaceae families growing in soil also had the highest 137Cs concentrations. The concentrations of 137Cs and stable Cs in mushroom samples were positively correlated. The concentration ratio of 137Cs/Cs differed between Agaricales and Aphyllophorales mushrooms. The average 137Cs/Cs ratio in mushrooms growing in soil was similar to that calculated for the top soil (<5 cm deep) alone because the mycelia of the mushrooms were mainly distributed near the surface of the soil. 相似文献
994.
995.
Tatsuya Nakamura Fuminori Sugihara Hisashi Matsushita Yoshichika Yoshioka Shin Mizukami Kazuya Kikuchi 《Chemical science》2015,6(3):1986-1990
Multifunctional mesoporous silica nanoparticles (MSNs) are good candidates for multimodal applications in drug delivery, bioimaging, and cell targeting. In particular, controlled release of drugs from MSN pores constitutes one of the superior features of MSNs. In this study, a novel drug delivery carrier based on MSNs, which encapsulated highly sensitive 19F magnetic resonance imaging (MRI) contrast agents inside MSNs, was developed. The nanoparticles were labeled with fluorescent dyes and functionalized with small molecule-based ligands for active targeting. This drug delivery system facilitated the monitoring of the biodistribution of the drug carrier by dual modal imaging (NIR/19F MRI). Furthermore, we demonstrated targeted drug delivery and cellular imaging by the conjugation of nanoparticles with folic acid. An anticancer drug (doxorubicin, DOX) was loaded in the pores of folate-functionalized MSNs for intracellular drug delivery. The release rates of DOX from the nanoparticles increased under acidic conditions, and were favorable for controlled drug release to cancer cells. Our results suggested that MSNs may serve as promising 19F MRI-traceable drug carriers for application in cancer therapy and bio-imaging. 相似文献
996.
Md. Zahangir Alam Teppei Yoshioka Tomonari Ogata Takamasa Nonaka Seiji Kurihara 《Liquid crystals》2007,34(10):1215-1219
Photochromic chiral azobenzene compounds with different molecular structures were synthesized, and a cholesteric phase was induced by mixing each chiral azobenzene compound with a non-photochromic chiral compound in a host nematic liquid crystal, E44. Helical pitch and, thus, helical twisting powers (HTP) of the chiral azobenzene compounds and the non-photochromic chiral compound were determined by Cano's wedge method. Molecular structures of the chiral azobenzene compounds were predicted by means of determining their molecular aspect ratio (L/D) with semiempirical molecular calculations (MOPAC at PM3 level). The effects of molecular structure on HTP of the chiral azobenzene compounds are studied in detail. Molecular structures of chiral azobenzene compounds significantly influence their HTPs. 相似文献
997.
998.
Nam‐Ho You Yasuhiro Nakamura Yasuo Suzuki Tomoya Higashihara Shinji Ando Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2009,47(19):4886-4894
A series of aromatic polyimides (PIs) containing pyridazine or pyrimidine in their main chains has been developed. All of the PIs were prepared from newly synthesized diamines, 3,6‐bis(4‐aminophenylenesulfanyl)pyridazine (APP), 4,6‐bis(4‐aminophenylenesulfanyl)pyrimidine (APPM) and aromatic dianhydrides, 4,4′‐[p‐thiobis(phenylenesulfanyl)]diphthalic anhydride (3SDEA) and 4,4′‐oxydiphthalic anhydride (ODPA) via the conventional two‐step polycondensation. The PIs showed good thermal stability with 10% weight loss at temperatures above 450 °C and glass transition temperatures above 190 °C. Films with a 10‐μm thickness exhibited good optical transparency above 80% at 500 nm, high refractive indices ranging from 1.7218 to 1.7499, and low birefringence between 0.0066 and 0.0102. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4886–4984, 2009 相似文献
999.
1000.
Iwao Yoshioka 《Topology and its Applications》2007,154(9):1980-1992
This paper deals with the study of closed images or quasi-perfect images of Nagata spaces, contraconvergent spaces, weak contraconvergent spaces, ks-spaces, γ-spaces and wγ-spaces and, of metrization theorems involving these spaces. We prove that the closed images of contraconvergent (weak contraconvergent) spaces are contraconvergent (weak contraconvergent) and that quasi-perfect images of γ- (wγ-)spaces are γ (wγ). 相似文献