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991.
992.
Hidefumi Yoshii Aya Sakane Daisuke Kawamura Tze Loon Neoh Hayato Kajiwara Takeshi Furuta 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):591-596
The release kinetics of (−)-menthol from chewing gum was investigated using various encapsulated powder of (−)-menthol. The
apparatus of flavor release of chewing gum was made with a glass container of mashing homogenizer. Flavor release behavior
could be correlated with Avrami’s equation. Chewing gum containing (−)-menthol/γ-CD complex powder had longer retention of
(−)-menthol compared with the β-CD complex powder and the (−)-menthol encapsulated in modified starches. The activation energies
of (−)-menthol release from chewing gum were 106 kJ/mol for γ-CD complex and 74 kJ/mol for (−)-menthol/β-CD complex powder
and emulsified (−)-menthol encapsulated in HI-CAP, respectively. 相似文献
993.
Takeshi Sakai Takehiko Yagi Ryosuke Takeda Toshiki Hamatani Yuki Nakamoto Hirokazu Kadobayashi 《高压研究》2020,40(1):12-21
ABSTRACTBoth micro-paired and conical support type double-stage diamond anvil cells (ds-DAC) were tested using a newly synthesized ultra-fine nano-polycrystalline diamond (NPD). Well-focused X-ray sub-micron beam and the conically supported 2nd stage anvils (micro-anvils) with 10?μm culet enable us to obtain good quality X-ray diffraction peaks from the sample at around 400?GPa. The relationship between confining pressure and sample pressure depends heavily on the initial height (thickness) of micro-anvils, the difference of a few micrometers leads to a quite different compression path. The conical support type is a solution to retain both enough thickness and strength of micro-anvils at higher confining pressure conditions. All conical support ds-DAC experiments terminated by the failure of the 1st stage anvil instead of 2nd one. The combination of ultra-fine NPD 2nd stage anvil and NPD 1st stage anvil opens a new frontier for measurement of the X-ray absorption spectrum above 300?GPa. 相似文献
994.
Efficient synthetic methods were established for obtaining 2-fluorobenzofurans involving various substituents. Upon being treated with 1,8-diazabicyclo[5.4.0]undec-7-ene under microwave irradiation, the α-unsubstituted β,β-difluoro-o-hydroxystyrenes underwent nucleophilic 5-endo-trig cyclization to afford the corresponding 2-fluorobenzofurans in high yields. Furthermore, 2-fluoro-3-iodobenzofuran was successfully synthesized, and its transformation to various 3-substituted 2-fluorobenzofurans was demonstrated. 相似文献
995.
Dr. Takeshi Fujita Yutaro Kobayashi Dr. Ikko Takahashi Ryutaro Morioka Dr. Tomohiro Ichitsuka Prof. Dr. Junji Ichikawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103643
Nickel-catalyzed reductive cross-coupling of allylic difluorides with aryl iodides was achieved via allylic C−F bond activation. Based on this protocol, a series of γ-arylated monofluoroalkenes were synthesized in moderate to high yields with high Z-selectivities. Mechanistic studies suggest that the C−I bonds of the aryl iodides and the C−F bonds of the allylic difluorides were cleaved via oxidative addition and β-fluorine elimination, respectively, where the oxidative addition of less reactive C−F bonds was avoided to permit their transformation. 相似文献
996.
Park Jae-Hyeok Hagio Takeshi Kamimoto Yuki Ichino Ryoichi 《Journal of Solid State Electrochemistry》2021,25(6):1901-1913
Journal of Solid State Electrochemistry - As a new trial to improve the corrosion resistance of the Fe-W alloy platings, Fe-W alloys incorporating a small amount of Zn, namely novel ternary Fe-W-Zn... 相似文献
997.
Shusuke Okamoto Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2019,57(16):1723-1729
Radical ring‐opening polymerization of 1,1‐dicyano‐2‐vinylcyclopropane 1 was performed in benzonitrile to find the corresponding homopolymer 2 soluble in organic solvents was successfully obtained while that in other solvents gave crosslinked and thus insoluble homopolymer. In addition, 1 underwent radical copolymerization with 1‐cyano‐1‐ester‐2‐vinylcyclopropanes 3 and 4 to afford the corresponding copolymers 7 and 8 . By increasing the content of the 1 ‐derived unit in the resulting copolymers, the solubility of the copolymers in organic solvents became lower and the residual weights at 600 °C and their glass transition temperatures became higher. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1723–1729 相似文献
998.
Yuri Sekimoto Arisa Tokai Muneshige Aritaki Takeshi Ando Takeshi Masuda 《Electrophoresis》2022,43(11):1233-1241
The accurate identification of animal species used for fur is important for conserving endangered animals, stopping illegal fur distribution, and addressing consumer concerns. Animal species used for fur are currently differentiated by observing species-specific morphological fur-hair features through a microscope. Although this method is simple, the results may differ among inspectors owing to its subjective nature. To develop an objective approach for differentiating animal species based on fur, we utilized the electrophoretic patterns of fur-hair proteins. First, we optimized protein extraction methods to produce clear electrophoretic patterns from fur-hair proteins. Then, we obtained 324 electrophoretic patterns from 54 fur samples belonging to 24 different animals; 216 of the 324 patterns were used for the construction of a discrimination model using two-way orthogonal partial least squares discriminant analysis. The model correctly discriminated between all the remaining 108 patterns without any false negatives or positives. Moreover, this model could discriminate between fur samples from closely related species that are difficult to distinguish using conventional microscopic identification because of the visual similarity of the fur hairs. 相似文献
999.
1000.
Dr. Kouzou Matsumoto Sota Kugo Dr. Daisuke Takajo Prof. Dr. Akira Inaba Dr. Yasukazu Hirao Dr. Hiroyuki Kurata Prof. Dr. Takeshi Kawase Prof. Dr. Takashi Kubo 《化学:亚洲杂志》2012,7(1):225-232
A series of tetrahedral oligothiophenes bearing n‐hexyl groups at the α‐positions of the terminal thiophene rings, (n‐C6H13(C4H2S)n)4C (Hex‐TnTM; n=1–4), has been synthesized by Kosugi–Migita–Stille coupling as a key reaction. Thanks to the improved solubility afforded by the terminal n‐hexyl groups, the largest homologue (n=4) was successfully obtained. Whereas the smaller derivatives (n=1, 2) were obtained as liquid substances, the larger derivatives (n=3, 4) were obtained as solids. Hex‐T3 TM partially adopts syn conformations between the adjacent thiophene rings in the crystal, probably owing to the packing force. Hex‐T3 TM not only appeared in the crystalline state but also the amorphous state, which was stable to up to 80 °C. Regardless of the terminal groups, the derivatives of n=2 exhibited a broad fluorescence with large Stokes shifts compared to the corresponding linear analogues, thereby suggesting the presence of intramolecular interactions between the bithiophene moieties. Interactions between terthiophene branches was also suggested in the radical cations of Hex‐T3 TM by cyclic voltammetry measurements. 相似文献