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191.
Atsushi Sudo Kyohei Nishiyama Mika Morimoto Shinichiro Yamamoto 《Journal of polymer science. Part A, Polymer chemistry》2020,58(14):1973-1981
Dimethacrylates with rigid adamantane-like cores were synthesized from myo-inositol orthoester via a sequence of (a) acylation or silylation of the equatorially oriented hydroxyl group, followed by (b) attachment of methacrylate groups on the axially oriented hydroxyl groups. The radical homopolymerization of these compounds proceeded via cyclopolymerization without crosslinking, as the two axially oriented methacrylate groups were fixed in close proximity with each other. The dimethacrylates underwent radical copolymerization with methyl methacrylate (MMA) to afford the corresponding polymethacrylates, exhibiting high glass transition temperatures (Tg), due to the introduction of the rigid orthoester moieties originating from the monomers and the macrocyclic structures formed via intramolecular cyclization of the two methacrylate groups of the monomers. The polymers obtained by polymerization of the dimethacrylate bearing a silylated hydroxyl group served as precursors of hydroxyl-bearing polymers, which also exhibited high Tg due to the formation of a hydrogen bonding network between the hydroxyl groups. 相似文献
192.
As a part of studies of the microscopic behavior of spins in a mixed compound with competing exchange interactions Fe
x
Mn1–x
TiO3, the Mössbauer technique has been applied to the samples withx=0.05, 0.10 and 0.20 which establish the antiferromagnetic long-range order at the respectiveT
N's and do not show reentrant transitions at lower temperatures. We have found that in each of the three samples, the paramagnetic doublet superimposes on the magnetically split spectrum belowT
N. The peak intensity of the paramagnetic doublet decreases with decreasing temperature and the paramagnetic doublet becomes undetected as sharp peaks at a temperature aroundT
N/2. However, the spectra observed at temperatures lower thanT
N/2 suggest that the paramagnetic doublet still exists, though it is highly broadened. This is interpreted as that short-range clusters of spins fluctuating rather slowly with time coexist with the spins forming the antiferromagnetic long-range order. We consider that these short-range clusters are responsible for the existence of the paramagnetic component contributing to the magnetization versus temperature curve. 相似文献
193.
Noriko Nakagawa Takafumi Yamada Koji Akioka Susumu Okubo Shojiro Kimura Hitoshi Ohta 《International Journal of Infrared and Millimeter Waves》1998,19(2):167-176
New systems for millimeter and submillimeter wave ESR have been developed in Kobe University. In the previous system the pulsed magnetic field was limited up to 17 T in the temperature range from 1.8 to 86 K. Using the new systems, we can measure in the field range up to 30 T in the temperature range from 1.8 K to 4.2 K and from 18 K to room temperature. The resolution of the magnetic field has been also improved in the new ESR system. The details of our new ESR systems are presented. In addition, the measurements of Yb2Cu2O5 using these new systems are presented. 相似文献
194.
195.
The theoretical research on stress waves propagating in laminated composites has been reported by many authors. However, there
has been little work on experimental studies of stress waves in those materials. This paper presents an experimental investigation
on stress waves propagating parallel to the layers of a laminated composite. A sandwich laminated composite consisting of
two aluminum facings and an epoxy core is used as a specimen. The stress wave in the specimen is observed by use of high-speed
holographic interferometry with a pulsed laser. In order to obtain the relative fringe orders, the interference fringe pattern
in the reconstructed image is treated as an image-processing system with a personal computer. For the calculation of the in-plane
displacement, an approximate relative-fringe-order method is used. The in-plane displacements obtained at some sampling points
on the surface are smoothed by using a spline function. Distributions of the in-plane displacement and the shear stress are
then obtained quantitatively over the whole analyzed field. 相似文献
196.
197.
The morphology of and electron tunneling through single and cluster cytochrome c molecules deposited on self-assembled dodecanthiol monolayer film on a gold substrate have been studied experimentally using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy. STM images of a single cytochrome c molecule revealed a globular structure with a diameter of 4 nm and height of 1.5 nm. A spectroscopic study obtained by recording tunneling current–bias voltage (V–I) curves revealed that the STM current increases stepwise at asymmetric threshold sample bias voltages of +100 mV and –200 mV. 相似文献
198.
Noriko Hirata-Kohno 《Inventiones Mathematicae》1991,104(1):401-433
Dans ce papier, nous donnons des minorations de combinaisons linéaires à coefficients algébriques de logarithmes de points algébriques sur les groupes algébriques commutatifs: soitG un groupe algébrique commutatif connexe défini sur la clôture algébriqueQ de dans , et soitvT
G
() un point de l'espace tangent dont l'image exp
G
(v) par l'exponentielle deG appartient àG(Q). On cherche à minorer la distance du pointv aux hyperplansW deT
G
(), rationnels surQ, qui ne passent pas parv. Cette minoration dépend, entre autres, d'un majorantB de la hauteur usuelle des coefficients d'une forme linéaire définissantW. LorsqueG est un groupe linéaire, il s'agit de minorer une combinaison linéaire de logarithmes de nombres algébriques, et la méthode de A. Baker permet d'obtenir une minoration
相似文献
199.
200.
A Cell‐Targeted Non‐Cytotoxic Fluorescent Nanogel Thermometer Created with an Imidazolium‐Containing Cationic Radical Initiator 下载免费PDF全文
Dr. Seiichi Uchiyama Dr. Toshikazu Tsuji Kyoko Kawamoto Dr. Kentaro Okano Eiko Fukatsu Takahiro Noro Kumiko Ikado Sayuri Yamada Yuka Shibata Dr. Teruyuki Hayashi Dr. Noriko Inada Dr. Masaru Kato Dr. Hideki Koizumi Prof. Hidetoshi Tokuyama 《Angewandte Chemie (International ed. in English)》2018,57(19):5413-5417
A cationic fluorescent nanogel thermometer based on thermo‐responsive N‐isopropylacrylamide and environment‐sensitive benzothiadiazole was developed with a new azo compound bearing imidazolium rings as the first cationic radical initiator. This cationic fluorescent nanogel thermometer showed an excellent ability to enter live mammalian cells in a short incubation period (10 min), a high sensitivity to temperature variations in live cells (temperature resolution of 0.02–0.84 °C in the range 20–40 °C), and remarkable non‐cytotoxicity, which permitted ordinary cell proliferation and even differentiation of primary cultured cells. 相似文献
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