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1.
Katoh Katsumi Fukui Satomi Haba Ayane Higashi Eiko Saburi Tei Okada Ken 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7563-7571
Journal of Thermal Analysis and Calorimetry - Nitrocellulose (NC) is prone to spontaneous decomposition with exothermic heat release and thus is generally evaluated for stability during the storage... 相似文献
2.
Dr. Manussada Ratanasak Takumi Murata Taishin Adachi Prof. Jun-ya Hasegawa Prof. Tadashi Ema 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(58):e202202210
BPh3 catalyzes the N-methylation of secondary amines and the C-methylenation (methylene-bridge formation between aromatic rings) of N,N-dimethylanilines or 1-methylindoles in the presence of CO2 and PhSiH3; these reactions proceed at 30–40 °C under solvent-free conditions. In contrast, B(C6F5)3 shows little or no activity. 11B NMR spectra suggested the generation of [HBPh3]−. The detailed mechanism of the BPh3-catalyzed N-methylation of N-methylaniline ( 1 ) with CO2 and PhSiH3 was studied by using DFT calculations. BPh3 promotes the conversion of two substrates (N-methylaniline and CO2) into a zwitterionic carbamate to give three-component species [Ph(Me)(H)N+CO2−⋅⋅⋅BPh3]. The carbamate and BPh3 act as the nucleophile and Lewis acid, respectively, for the activation of PhSiH3 to generate [HBPh3]−, which is used to produce key CO2-derived species, such as silyl formate and bis(silyl)acetal, essential for the N-methylation of 1 . DFT calculations also suggested other mechanisms involving water for the generation of [HBPh3]− species. 相似文献
3.
4.
Many operators in Banach spaces occur as the integration operator of a suitable vector measure; their compactness is completely described in [19]. However, many important spaces X in analysis (and integration operators in such spaces) do not fall into this scheme because X is not normable. Characterizing the compactness of integration operators in this setting is the aim of this note. The methods and techniques employed are quite different to the Banach space arguments used in [19]. 相似文献
5.
The binding properties of metal ions to a pectic polysaccharide, rhamnogalacturonan II (RG-II), from plant cell walls were analyzed by size-exclusion HPLC/ICP-MS. The dimeric RG-II borate complex (dRG-II-B) from sugar beet and red wine contained 0.8 - 1.1 mol/mol of B, 0.8 - 1.1 mol/mol of Ca, 0.1 - 0.3 mol/mol of Sr, and 0.03 - 0.07 mol/mol of Ba. The treatment of dRG-II-B with Sr2+, Ba2+, Pb2+ or La3+ exchanged the originally present Ca, Sr and Ba. In contrast, monomeric RG-II (mRG-II), which contained approximately 0.1 mol/mol of Ca, formed complexes with La3+, Eu3+, and Lu3+ added to the solution, but did not do so with Ca2+, Sr2+, Ba2+ and Pb2+. The HPLC/ICP-MS and HPLC/RI (refractive index detector) analysis of the partially hydrolyzed mRG-II that was treated with La3+ indicated that the side chains and backbone of mRG-II together form a lanthanoid binding site. 相似文献
6.
In this paper, we hall discuss the projective flatness of complex Finsler metrics by investigating the geometry of projective bundles associated with a holomorphic vector bundle. 相似文献
7.
We shall give a direct proof of the independence result of a Buchholz style-Hydra Game on labeled finite trees. We shall
show that Takeuti-Arai's cut-elimination procedure of and of the iterated inductive definition systems can be directly expressed by the reduction rules of Buchholz's Hydra Game.
As a direct corollary the independence result of the Hydra Game follows.
Received: August 23, 1994 / Revised: July 24, 1995 and May 9, 1996 相似文献
8.
The initial stage of cubic silicon carbide (3C-SiC) growth on a Si(0 0 1) surface using dimethylsilane (DMS) as a source gas was observed using scanning tunneling microscopy (STM) and reflection high-energy electron diffraction (RHEED). It was found that the dimer vacancies initially existing on the Si(0 0 1)-(2 × 1) surface were repaired by the Si atoms in DMS molecules, during the formation of the c(4 × 4) surface. From the STM measurement, nucleation of SiC was found to start when the Si surface was covered with the c(4 × 4) structure but before the appearance of SiC spots in the RHEED pattern. The growth mechanism of SiC islands was also discussed based on the results of RHEED, STM and temperature-programmed desorption (TPD). 相似文献
9.
Sunanda Banerjee Rohini M Godbole Sreerup Raychaudhuri Ben Allanach Sunanda Banerjee Satyaki Bhattacharyya Debajyoti Choudhury Siba Prasad Das Anindya Datta Rohini M Godbole Monoranjan Guchait Sabine Kraml Gobinda Majumdar David Miller Margarete Mühlleitner Nobuchika Okada Maxim Perelstein Santosh K Rai Sreerup Raychaudhuri Saurabh D Rindani DP Roy K Sridhar Rishikesh Vaidya D Zeppenfeld 《Pramana》2006,67(4):617-637
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology
(WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these
problems by the subgroups formed during the workshop is included in this report. 相似文献
10.