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81.
82.
Tatsuro Ouchi Toshio Banba Hiroshi Masuda Tatsuji Matsumoto Shigeo Suzuki Masuko Suzuki 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):959-975
In order to provide a macromolecular prodrug of 5-fluorouracil (5FU) reducing the side effects, having an affinity for tumor cells, and exhibiting strong antitumor activity, the covalent attachments of 5FUs to chitosan and chitosamino-oligosaccharide (COS) through hexamethylene spacer groups via urea, urea bonds were carried out. The effect of prolongation of life was tested in vivo against p388 lyrnphocytic leukemia in female CDF, mice by intra-peritoneal (i.p.) transplantation/i.p. injection and the growth-inhibitory effect on Meth-A fibrosarcoma or MH-134Y heputoma was evaluated in vivo in SPF-C3H/He scl male or Balb/c male mice by subcutaneous (s.c.) implantation/intravenous (i.v.) injection. The effects of the degree of polymerization of chitosan and 相似文献
83.
We demonstrate reversible photoinduced in situ reorientation of low molecular mass liquid crystals (LCs) by means of photoaddressable polymers (PAPs). These polymers contain mesogenic azobenzene side chains optimized to reorient cooperatively and effectively upon illumination with polarized light. Various low molecular mass LCs were introduced between two PAP layers and these sandwich devices were tested with respect to stability and reversibility of photoinduced orientation. Dissolution of the PAP layer by the low molecular mass LC was observed for several material combinations and systematically investigated. Different anisotropic dyes were added as fluorescence markers in order to monitor the photoinduced LC orientation. With an optimized material combination, more than 10 reversible reorientation processes could be realized with polarized light of either 514 or 405 nm wavelength, without any reduction in alignment quality. Further, microscopic polarized fluorescence patterns could be produced and erased within short exposure times. 相似文献
84.
Shigekazu Usuda Kenichiro Yasuda Yoko Saito-Kokubu Fumitaka Esaka Chi-Gyu Lee Masaaki Magara 《International journal of environmental analytical chemistry》2013,93(9):663-675
From a viewpoint of physical and chemical form estimation, ultra-trace analytical techniques of nuclear materials in environmental samples for safeguards have been investigated at Japan Atomic Energy Research Institute. This article deals with (1) an outline of the developed techniques for bulk and particle analyses of uranium and plutonium in the safeguards environmental samples; (2) current R&D on techniques relating to estimation of the physical and chemical form, such as SEM images and EDX spectra for fine particles of nuclear materials and fission track observation applicable to fissile materials; and (3) possible analytical methodologies, as future works, applicable to ultra-trace amounts of nuclear materials in environmental samples. 相似文献
85.
Toshiaki Yamashita Shuhei Matsushita Takuya Nagatomo Ryosuke Yamauchi Masahide Yasuda 《Research on Chemical Intermediates》2013,39(1):111-126
Photoirradiation of Me2CO–H2O solution of pent-4-en-1-ol (1a) with a high-pressure mercury lamp in a test tube gave 8-hydroxyoctan-2-one (3a) in 66 % yield along with oxetane (4a) and the isomer (4a′) in 10 % yield. Irradiation of the running Me2CO–H2O solution of 1a in the flow system of a microchannel reactor (MCR) gave mainly 4a. The photoreaction of 1,1-diphenylethene (2a) with triethylamine gave a Markovnikov-type adduct (5a) and an anti-Markovnikov-type adduct (6a). The use of the MCR enhanced the production of 5a. These phenomena were explained by the light-path length effects of the MCR. 相似文献
86.
Prof. Dr. Tsutomu Ishi-i Honoka Tanaka Rihoko Kichise Christopher Davin Takaaki Matsuda Dr. Naoya Aizawa Dr. In Seob Park Prof. Dr. Takuma Yasuda Taisuke Matsumoto 《化学:亚洲杂志》2021,16(15):2136-2145
The regulation of multicolor fluorescence changes in mechanochromic fluorescence (MCF) remains a challenging task. Herein, we report the regulation of MCF using a donor-acceptor structure. Two crystal polymorphs, BTD-pCHO(O) and BTD-pCHO(R) produced by the introduction of formyl groups to an MCF dye, respond to a mechanical stimulus, allowing a three-color fluorescence change. Specifically, the orange-colored fluorescence of the metastable BTD-pCHO(O) polymorph changed to a deep-red color in the amorphous-like state to finally give a red color in the stable BTD-pCHO(R) polymorph. This change occurred by mechanical grinding followed by vapor fuming. The two different crystal packing patterns were selectively regulated by the electronic effect of the introduced functional groups. The two types of selectively formed crystals in BTD(F)-pCHO bearing fluorine atoms, and BTD(OMe)-pCHO bearing methoxy groups, respond to mechanical grinding, allowing for the regulation of multicolor MCL from a three-color change to two different types of two-color changes. 相似文献
87.
Li T Garg U Liu Y Marks R Nayak BK Rao PV Fujiwara M Hashimoto H Kawase K Nakanishi K Okumura S Yosoi M Itoh M Ichikawa M Matsuo R Terazono T Uchida M Kawabata T Akimune H Iwao Y Murakami T Sakaguchi H Terashima S Yasuda Y Zenihiro J Harakeh MN 《Physical review letters》2007,99(16):162503
The strength distributions of the giant monopole resonance (GMR) have been measured in the even-A Sn isotopes (A=112-124) with inelastic scattering of 400-MeV alpha particles in the angular range 0 degrees -8.5 degrees . We find that the experimentally observed GMR energies of the Sn isotopes are lower than the values predicted by theoretical calculations that reproduce the GMR energies in 208Pb and 90Zr very well. From the GMR data, a value of Ktau = -550 +/- 100 MeV is obtained for the asymmetry term in the nuclear incompressibility. 相似文献
88.
Organic Dicarboxylate Negative Electrode Materials with Remarkably Small Strain for High‐Voltage Bipolar Batteries 下载免费PDF全文
Dr. Nobuhiro Ogihara Tomomi Yasuda Yoshihiro Kishida Dr. Tetsu Ohsuna Kaito Miyamoto Dr. Nobuko Ohba 《Angewandte Chemie (International ed. in English)》2014,53(43):11467-11472
As advanced negative electrodes for powerful and useful high‐voltage bipolar batteries, an intercalated metal–organic framework (iMOF), 2,6‐naphthalene dicarboxylate dilithium, is described which has an organic‐inorganic layered structure of π‐stacked naphthalene and tetrahedral LiO4 units. The material shows a reversible two‐electron‐transfer Li intercalation at a flat potential of 0.8 V with a small polarization. Detailed crystal structure analysis during Li intercalation shows the layered framework to be maintained and its volume change is only 0.33 %. The material possesses two‐dimensional pathways for efficient electron and Li+ transport formed by Li‐doped naphthalene packing and tetrahedral LiO3C network. A cell with a high potential operating LiNi0.5Mn1.5O4 spinel positive and the proposed negative electrodes exhibited favorable cycle performance (96 % capacity retention after 100 cycles), high specific energy (300 Wh kg?1), and high specific power (5 kW kg?1). An 8 V bipolar cell was also constructed by connecting only two cells in series. 相似文献
89.
Minlang Yang In Seob Park Yasuhiro Miyashita Katsunori Tanaka Takuma Yasuda 《Angewandte Chemie (International ed. in English)》2020,59(33):13955-13961
Herein, the universal design of high‐efficiency stimuli‐responsive luminous materials endowed with mechanochromic luminescence (MCL) and thermally activated delayed fluorescence (TADF) functions is reported. The origin of the unique stimuli‐triggered TADF switching for a series of carbazole–isophthalonitrile‐based donor–acceptor (D–A) luminogens is demonstrated based on systematic photophysical and X‐ray analysis, coupled with theoretical calculations. It was revealed that a tiny alteration of the intramolecular D–A twisting in the excited‐state structures governed by the solid morphologies is responsible for this dynamic TADF switching behavior. This concept is applicable to the fabrication of bicolor emissive organic light‐emitting diodes using a single TADF emitter. 相似文献
90.