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141.
Kazuhisa Murata Kossi E. Bere Koichi Matano Takashi Hayakawa Satoshi Hamakawa Kunio Suzuki 《Reaction Kinetics and Catalysis Letters》2001,72(1):65-72
During the reaction of propylene with O2, in situ Diffuse Reflectance FT-IR measurements were performed over Ti-modified SZ and SZ catalysts. Without O2, the main bands characteristic of (branched) hydrocarbons, formed by oligomerization leading to, finally, carbonaceous residue, appeared within the range of 3900-2750 cm-1, which was affected by the bands of surface OH groups. Investigation of these IR bands showed the role of molecular oxygen not only to limit the formation of carbonaceous species on the catalyst surface, but also to form oxygenates and these findings were in good agreement with the results of catalytic reaction. 相似文献
142.
The carbonylative Stille coupling reaction of benzyl chlorides with allyltributylstannane was successfully conducted by using palladium nanoparticles as the catalyst under phosphine ligand-free conditions. The corresponding α,β-unsaturated ketone products were obtained in good to excellent yields. 相似文献
143.
Yoshinori SaitoYuriko Takashima Aya KamadaYurika Suzuki Midori SuenagaYasuko Okamoto Yoichi MatsunagaRyo Hanai Takayuki KawaharaXun Gong Motoo Tori Chiaki Kuroda 《Tetrahedron》2012,68(48):10011-10029
Root chemicals and DNA sequences were analyzed for Ligularia virgaurea collected in the northern Sichuan Province and adjacent areas of China. Thirty-eight samples were found to contain five chemotypes, two known and three new ones. From samples of the new chemotypes, 13 new compounds were isolated, including 3 sesquiterpene dimers and some rearranged eremophilanes. The DNA sequences suggested that the chemotype differentiation had a genetic origin. 相似文献
144.
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147.
Feroza Begum Yoshinori Namihira S. M. Abdur Razzak Shubi F. Kaijage Nguyen H. Hai Kazuya Miyagi Hiroki Higa Nianyu Zou 《Optical Review》2009,16(2):54-58
This research presents a simple index-guiding square photonic crystal fibers (SPCFs) that has a silica core surrounded by
air hole with two different diameters. It is demonstrated that the designed two-different-size hole-arrayed index-guiding
SPCFs has a ultra-flattened chromatic dispersion of 0 ± 0.9 ps/(nm·km) in a wavelength range of 1.34 to 1.61 μm and low confinement
loss of less than 10−7 dB/m in a wavelength range of 1.2 to 1.7 μm. It has also been shown that the proposed SPCFs show reasonable dispersion tolerance. 相似文献
148.
Dr. Yoshifumi Hashikawa Hui Li Prof. Dr. Yasujiro Murata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(27):7507-7511
Cage-opened bisfulleroids are one of suitable building blocks for making a large hole on fullerenes. This work focuses on the Diels-Alder reaction of C60 with azines, among synthetic methods developed thus far, to provide bisfulleroids. Surprisingly, the computational study predicted that the reaction proceeds with normal electron demand in contrast to hitherto considered inverse-electron-demand pathway. The benzoannulation to the pyridazine ring, i. e., phthalazine, resulted in the remarkably shortened reaction time due to the better interaction between the HOMO of phthalazine and the LUMO of C60 as well as stronger 2,3-diaza-1,3-butadiene character in the phthalazine as confirmed crystallographically. Contrary to expectations, the benzobisfulleroid was converted into corresponding orifice-enlarged derivative via the photooxygenation slightly faster than the fulleroid derived from pyridazine. 相似文献
149.
Pavle Tro?elj Anamarija Bri? Yasujiro Murata Davor Margeti? 《Structural chemistry》2012,23(3):791-799
Two novel polarofacial-[5]-polynorbornanes, O
2
N
2
O
2– and COCOC–, were synthesized by cycloaddition reactions and their molecular and crystal structures were determined. These hetero[5]polynorbornanes
posses heteroatoms at the norbornene bridges located at the outer convex surface, whereas functionalities are positioned on
the inner concave surface. Molecular structures attest the extent of the curvature of their polycyclic backbone, and established
that the COCOC-[5]-polynorbornane possesses more curved topology due to larger steric repulsion of 7-norbornane bridges. These experimental
results are in good agreement with computational predictions of geometry. Quantum chemical study has identified lone pair
repulsive interactions and steric repulsions of bridges as important factors for determining curvature. 相似文献
150.