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41.
Seiichi Taruta Maki Suzuki Tomohiko Yamakami Tomohiro Yamaguchi Kunio Kitajima 《Journal of Non》2008,354(10-11):848-855
In order to crystallize a large quantity of the lithium?mica in glass?ceramics, 5.1 mass% MgF2 was added to the starting materials of the parent glasses having chemical compositions of Li(1+x)Mg3AlSi3(1+x)O10+6.5xF2 (x = 0.5 and 1.0). Transparent glass?ceramics, in which a large quantity of lithium?mica with particle size of <50 nm was separated, could be prepared from the MgF2-added parent glass with x = 0.5. While the parent glass, which had a binodal phase separation structure, did not exhibit electrical conductivity, the transparent glass–ceramic was given conductivity by the formation of an interlocking structure of mica. As the separated mica formed a tighter interlocking structure, the conductivity increased and reached a value of 2.0 × 10?3 S/cm at 600 °C. The MgF2-added parent glass with x = 1.0 was not transparent because of coarse spinodal phase separation. The conductivity was 4.3 × 10?4 S/cm at 600 °C but was significantly decreased by the separation of mica. 相似文献
42.
Dr. Tetsuo Tsuchiya Dr. Tomohiko Nakajima Yuko Uzawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(42):9261-9276
This review summarizes the use of photoreactions that replace conventional heating processes for growing oxide thin films from chemical solutions. In particular, this review outlines key variables in photoreactions that affect epitaxial and polycrystalline thin film growth, including precursor materials, laser wavelength, laser fluence, and carbon. In addition, the features of the photoreaction process that can be controlled at a low temperature by oxygen non-stoichiometry are examined. Likewise, functions that are neither achieved by developing a gradient structure nor controlled by a thermal equilibrium reaction are detailed. Two new concepts are presented, known as photoreaction of nanoparticles (PRNP) and photoreaction of a hybrid solutions (PRHS), in which crystal nuclei are pre-dispersed in a metal–organic compound film. This method has successfully produced flexible phosphor films used as resistor or thermistor electronic components. Finally, thin film growth using different light sources such as flash lamps and femtosecond lasers (fs) is explored. 相似文献
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Photophysical Properties and Efficient,Stable, Electrogenerated Chemiluminescence of Donor–Acceptor Molecules Exhibiting Thermal Spin Upconversion
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Dr. Ryoichi Ishimatsu Dr. Tomohiko Edura Prof. Chihaya Adachi Prof. Koji Nakano Prof. Toshihiko Imato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4889-4898
The photophysical properties and electrogenerated chemiluminescence (ECL) of three donor–acceptor molecules composed of dicyanobenzene and methyl‐, tert‐butyl‐, and phenyl‐substituted carbazolyl groups, 1,2,3,5‐tetrakis(3,6‐disubstituted‐carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN‐Me, 4CzIPN‐tBu, and 4CzIPN‐Ph, respectively) are described. These molecules show delayed fluorescence as a result of thermal spin upconversion from the lowest triplet state to the lowest singlet state at room temperature. The three molecules showed yellow to yellowish–red ECL. Remarkably, the ECL efficiencies of 4CzIPN‐tBu in dichloromethane reached almost 40 %. Moreover, stable ECL was emitted from 4CzIPN‐tBu and 4CzIPN‐Ph. In case of 4CzIPN‐Me, the ECL intensity decreased during voltage cycles because of polymerization. Quantum chemical calculations revealed that polymerization was inhibited by the steric hindrance of the bulky tert‐butyl and phenyl groups on the carbazolyl moieties and lowered the spin density on the carbazolyl groups through electron conjugation for 4CzIPN‐Ph. 相似文献
45.
Masamichi Yamanaka Tomoe Nakagawa Ryohei Aoyama Tomohiko Nakamura 《Tetrahedron》2008,64(51):11558-11567
C3-Symmetry tris-urea low molecular weight gelator (LMWG) (1), which shows chemical stimuli responsible for a sol-gel phase transition, was divided into five regions. Based on the division, 22 derivatives were synthesized. The gelation ability of these derivatives was tested in nine organic solvents with a wide range of values for relative static permittivity (?r=47.2-1.89). Some derivatives showed a better performance as LMWGs than the original tris-urea LMWG (1). For example, the critical gelation concentration (CGC) in acetone was improved from 1.5 wt % to 0.5 wt % by changing the core substituent (18). Highly versatile LMWG for a variety of solvents was obtained by changing the linker moiety (23). Structural information to design tris-urea LMWGs is important to create rationally a functional supramolecular gel. 相似文献
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Fluorescent polymeric thermometers consisting of only N-alkylacrylamide and fluorescent components show rather low temperature resolution in their functional ranges (ca. 15-50 degrees C) because of the occurrence of intermolecular aggregation, which causes hysteresis in their fluorescence response to changes in temperature. By adding an ionic component to prevent such intermolecular aggregation, we obtained four fluorescent polymeric thermometers that offer high temperature resolution (<0.2 degrees C). Each new fluorescent polymeric thermometer covered the temperature range, 9-33 degrees C, 30-51 degrees C, 49-66 degrees C or 4-38 degrees C. 相似文献
48.
Kobayashi M Takashima A Ishii T Naka H Uchiyama M Yamaguchi K 《Inorganic chemistry》2007,46(4):1039-1041
We have obtained a novel heterobimetallic iron-magnesium complex, (THF)4Mg(mu-Br)2FeBr2 (THF = tetrahydrofuran), which showed reverse photochromism in THF. The response exhibited in this system is associated with d-orbital splitting of the Fe atom and a change in the molecular aggregation state (dimerization). 相似文献
49.
Suematsu NJ Ogawa Y Yamamoto Y Yamaguchi T 《Journal of colloid and interface science》2007,310(2):648-652
Nanoparticles self-assembled into ring-shaped aggregates that were arranged in a two-dimensional (2D) hexagonal pattern. This hierarchic pattern was prepared by casting a toluene solution composed of polystyrene (PS) and Ag nanoparticles (NP). Dewetting of the thin composite layer induced the mesoscopic hexagonal array of PS-NP droplets. Within each dried droplet (dot), Ag nanoparticles self-assembled into a spot- or a ring-shaped 2D superlattice alternatively depending on the size of the dot, which was controlled by the molecular weight of PS. 相似文献
50.