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181.
Takumi Taninaka Kohji Iwamoto Yuji Minoura 《Journal of polymer science. Part A, Polymer chemistry》1977,15(9):2219-2227
The effect of some organic halides on the cationic polymerization of styrene (St) initiated by phosphorus trichloride (PCl3) was studied to clarify the initiation mechanism on the cationic polymerization. Addition of organic halides caused an acceleration to some extent. Further, cationic graft copolymerization of St onto poly(vinyl chloride) and polychloroprene was carried out. In each case, grafting efficiency was lower than 10%. These results in the cationic polymerization of St by PCl3 in nitrobenzene support the assumption that the initiation step is caused by the dissociation of two molecules of PCl3 to ion pairs. 相似文献
182.
Zhi Qin Ono A. Wenxin Li Lili Zhao Tongyu Sun Ambe S. Ohkubo Y. Iwamoto M. Kobayashi Y. Maeda H. Ambe F. 《Zeitschrift für Physik A Hadrons and Nuclei》1975,272(3):315-319
The radiative decays of 4.7 d119m Te and 16 h119g Te have been re-investigated. Compared to previous investigations, almost twice more transitions have been observed. Revised decay schemes are proposed in which most of the observed transitions are attributed. The half lives of the levels at 270.45 keV (g 7/2), 644.01 keV (s 1/2), 1212.69 keV (9/2+) and 1366.15 keV (h 11/2) have been measured by means of the delayed coincidence method and found to be 35±10ps, <10ps, <10 ps and 112±15 ps respectively. The states are discussed in the framework of current models. 相似文献
183.
184.
Benzoin reactions are catalyzed effectively by a methylene-bridged bis(benzimidazolium) salt to yield alpha-hydroxy ketones, and the reactions proceed in water as the aqueous medium under mild conditions. 相似文献
185.
Microscopic observation and characterization of the oil bridge between dehulled-roasted sesame seeds
Takenaka N Iwamoto S Yabe T Yamauchi R Ogata K Kato K 《Colloids and surfaces. B, Biointerfaces》2007,55(2):131-137
The formation of an oil bridge between adhesive seeds was observed microscopically. The geometry of the oil bridge was affected by the shape of the adhesive seeds. The capillary force of the oil bridge was estimated from the image captured by the microscope. The average capillary force was 127 μN, which was five times higher than the average gravity of the seeds. It was observed that several oil bridges formed between two seeds. These results indicated an adequate ability of the seeds to adhere. The capillary force of the oil bridge increased with surface oil content. The probability of formation of an oil bridge increased with surface oil content when the surface oil content was above 0.63%. The probability of formation of an oil bridge markedly increased when sucrose was added to the seeds. 相似文献
186.
Koji Kubota Keiichi Hayama Hiroaki Iwamoto Prof. Dr. Hajime Ito 《Angewandte Chemie (International ed. in English)》2015,54(30):8809-8813
The enantioselective borylative dearomatization of a heteroaromatic compound has been achieved using a copper(I) catalyst and a diboron reagent. This reaction involves the regio‐ and enantioselective addition of active borylcopper(I) species to indole‐2‐carboxylates, followed by the diastereoselective protonation of the resulting copper(I) enolate to give the corresponding chiral indolines, which bear consecutive stereogenic centers. 相似文献
187.
Shimosaka T Iwamoto K Izako M Suzuki A Uchiyama K Hobo T 《Micron (Oxford, England : 1993)》2004,35(4):297-302
Non-destructive measurement of a small region on a solid/liquid interface is of great importance in physical chemistry and biochemistry, especially in the research of thin films and cell membranes. Optical methods for surface analysis with high lateral resolution are suitable methods for monitoring them. We now report a new scanning optical microscopic method to which total internal reflection coupled with a thermal lens technique was introduced. Its lateral resolution was estimated both experimentally and theoretically. To experimentally estimate the resolution, the grid patterns of thin photoresist films with well-defined lateral structures were measured. The experimental resolution was about 45 microm, which was almost same as the diameter of the excitation beam at a glass/sample interface. From this result, it was verified that this new scanning microscopy ideally worked. 相似文献
188.
Eiji Tayama Ryota Sato Keisuke Takedachi Hajime Iwamoto Eietsu Hasegawa 《Tetrahedron》2012,68(24):4710-4718
Selective amine de-alkylation enables the conversion of Sommelet–Hauser rearrangement products into 2-aryl-2-bromoacetic acid derivatives. These compounds are valuable synthetic intermediates in the synthesis of α-aryl-α-amino or α-aryl-β-amino acid derivatives. The method presented herein is a formal de-N,N-dialkylation of Sommelet–Hauser rearrangement products. 相似文献
189.
190.
Analyzing spectroscopic optical properties of an organic double-layer diode comprised of α-NPD and Alq3 layers, we studied the selectively probing of electric field distribution in one of the two layers by using the microscopic electric field induced optical second harmonic generation (EFISHG) measurement. Spectroscopic SHGs from Indium–Zinc-Oxide/N,N-Di(naphthalene-1-yl)-N,N′-diphenyl-benzidine/tris(8-quinolinolato) aluminium/Al (IZO/α-NPD/Alq3/Al) diodes were measured. Results showed that the SHG peaks were generated at 940 and 1050 nm from the α-NPD and Alq3 layers, respectively, due to the EFISHG process, and the electric field in each layer can be selectively probed. The contribution of the accumulated charge at the double-layer α-NPD and Alq3 interface was also identified by the d.c. voltage dependence on the EFISHG intensity. 相似文献