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991.
992.
Satoshi Kometani Tomoki Kato Kei Manabe Tamio Seko Yu-Ning Chang Huai-Rou Luo Yoshihiro Agata Noboru Ohta Teruaki Hayakawa Syuji Fujii Yoshinobu Nakamura Ming-Chia Li Tomoyasu Hirai 《Journal of polymer science. Part A, Polymer chemistry》2022,60(5):766-773
A novel block copolymer containing polyhedral oligomeric silsesquioxanes (POSS) features a well-controlled stereoregularity, that is, isotactic polymethacrylate-functionalized POSS-b-polymethyl methacrylate (it-PMAPOSS-b-PMMA), was prepared via controlled-anionic polymerization. The stereoregularity of each segment in the it-PMAPOSS-b-PMMA is evaluated using nuclear magnetic resonance (NMR) spectroscopy, which reveals an isotactic configuration in both the PMAPOSS and PMMA segments. The secondary structure of it-PMAPOSS-b-PMMA in a mixture with a small chiral dopant is clarified with electronic circular dichroism and vibrational circular dichroism measurements. By adding a chiral dopant, a controlled preferential helical conformation of the unilateral segment in achiral it-PMAPOSS-b-PMMA is achieved. 相似文献
993.
994.
From the viewpoints of environmental protection, support for the aged and ensuring the right to mobility, there is a need to develop a new type of mobility vehicle that provides more effective transportation. The authors propose an inverted pendulum vehicle with pedals as one of the forms of personal mobility vehicles (PMVs). In this paper, the steering performance of the inverted pendulum vehicle with pedals is discussed based on experiments on a prototype. From the experimental results, it was confirmed that the errors from the five subjects for the target trajectory and the five-grade evaluation of the maneuverability were similar. Finally, we created an inverted pendulum vehicle with pedals to which was added a reaction actuator for the steering system. From the experimental results, it was found that setting appropriate feedback gains for the handle steering angle and its rate of rotation, which control the right and left wheel driving torques, resulted in greatly improved maneuverability. 相似文献
995.
Tatsuhito Wakigawa Toshihiko Nagano Yoshihiro Kangawa Koichi Kakimoto 《Journal of Crystal Growth》2008,310(11):2827-2831
We performed synthesis of AlN using Al and Li3N. In this method, there are two problems that must be solved for obtaining single-phase AlN. One of them is suppression of Li3AlN2 formation and the other is precipitation of LiAl from the residual source materials during the cooling process. In the present work, we analyzed phase stability of products and found that AlN was stable at high temperatures and low Li–N/Al molar ratios. However, the products still contained LiAl and Al. Therefore, we examined the effectiveness of vapor phase epitaxy for separating AlN from the extra phase (LiAl and Al formed from residual source materials). From the experimental results, feasibility of vapor phase epitaxy was confirmed. That is, we can deposit only an AlN layer on a sapphire substrate by optimizing the growth conditions, i.e., temperature range above 1150 °C and Li–N/Al molar ratio less than 1. 相似文献
996.
Hiromitsu Maeda Prof. Dr. Yoshihiro Ito Yohei Haketa Nazuki Eifuku Eunji Lee Myongsoo Lee Prof. Dr. Takeshi Hashishin Dr. Kenji Kaneko Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3706-3719
Just subtract water : Amphiphilic π‐conjugated acyclic oligopyrroles form solvent‐assisted H‐aggregates that give rise to vesicular structures in aqueous solution (see figure). The H‐aggregates are sensitive to the conditions and are transformed into J‐aggregates by the removal of water.
997.
Toshihide Maki Dr. Shinya Iikawa Gen Mogami Hitomi Harasawa Yoshihiro Matsumura Prof. Dr. Osamu Onomura Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(21):5364-5370
Get selective! A selective oxidation of 1,2‐diols to α‐hydroxyketones catalyzed by organotin compounds has been developed (see scheme). Invaluable chemo‐ and stereoselectivity were found in the reaction. The catalytic system has been achieved by electrochemical and chemical oxidation.
998.
To achieve label-free detection of amino acids in capillary-based electrokinetic chromatography-thermal lens microscopy (EKC-TLM), gold nanoparticles (GNPs), which possess the absorption around 500nm attributed to surface plasmon resonance (SPR), were added to the background solution (BGS). Since the SPR absorption of the GNPs exhibits a sensitive response toward environmental changes and the degree of aggregation, the sensitive detection of non-absorbing species is expected by using the GNPs in EKC-TLM (GNP-EKC-TLM). In the GNP-EKC-TLM analysis of glutamic acid (Glu), a sharp peak was observed when the GNPs were added to the BGS. The plot of the peak area of Glu against its concentration gave a good linear relationship and the limit of detection was estimated to be 25mug/mL. Furthermore, a baseline separation of lysine and Glu was successfully achieved. Thus, the EKC separation and label-free TLM detection of the amino acids can be realized only by adding the GNPs into the BGSs. 相似文献
999.
Crystal structures and magnetic properties of the ternary oxides Ln3NbO7 (Ln=La, Pr, Nd, Sm-Lu) are reported. Their powder X-ray diffraction measurements and Rietveld analyzes show that they have the fluorite-related structures with space group Pnma (Ln=La, Pr, Nd), C2221 (Ln=Sm-Tb), or Fm-3m (Ln=Dy-Lu). Magnetic susceptibility measurements were carried out from 1.8 to 400 K. The Ln3NbO7 compounds for Ln=Pr, Gd, Dy-Yb show Curie-Weiss paramagnetic behavior, and Sm3NbO7 and Eu3NbO7 show van Vleck paramagnetism. On the other hand, two magnetic anomalies were observed for both Nd3NbO7 (0.6 and 2.7 K) and Tb3NbO7 (2.0 and 3.2 K). From the results of specific heat measurements, it was found that these anomalies are due to the antiferromagnetic ordering of Ln ions in two different crystallographic sites (the 8-coordinated and 7-coordinated sites). 相似文献
1000.
Takashi Makino Yoshihiro Ogura Yuuki Matsui Takeshi Sugahara Kazunari Ohgaki 《Fluid Phase Equilibria》2009
The isothermal phase equilibria of the carbon dioxide + cyclopropane mixed-gas hydrate system were investigated by means of static temperature measurement and Raman spectroscopic analysis. Raman spectra indicated that the crystal structure of the carbon dioxide + cyclopropane mixed-gas hydrate changes from structure-I to structure-II and back to structure-I with an increase of the equilibrium carbon dioxide composition at 279.15 K, while each simple gas hydrate belongs to structure-I at the temperature. Whereas, unlike 279.15 K, no structural phase transition occurs along the isothermal stability boundary at 284.15 K. 相似文献