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141.
Hiroshi Itokawa Nobuaki Yasutake Shintaro Okamoto Ichiro Mizushima 《Applied Surface Science》2008,254(19):6135-6139
Embedded silicon carbon alloy (e-Si:C) technology for source and drain (S/D) is expected to improve nMOSFET drive current. The distribution and activation characteristics of arsenic in Si:C film and the interfacial solid-phase reaction of the Ni/Si:C system were studied with the aim of achieving the maximum improvement of the characteristics of e-Si:C S/D. It was clarified that the active carrier concentration of Si:C decreased with increasing carbon concentration compared to the control Si. There is concern that the low doping activation in Si:C increases series resistance of e-Si:C S/D nMOSFETs and degrades the performance gain expected from the strain effect. 相似文献
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143.
Dr. Yoshifumi Sasano Dr. Yohei Haketa Hiroki Tanaka Dr. Nobuhiro Yasuda Prof. Ichiro Hisaki Prof. Hiromitsu Maeda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(27):6712-6717
Phenyl groups were introduced at the β-positions proximal to the meso-hydroxy moiety in hydroxyporphyrin NiII complexes by oxidized BINAP PdII complexes. Ion-pairing assemblies of deprotonated π-electronic anions, anionic site of which was stabilized by the introduced phenyl moieties with a bulky cation, were formed. They showed charge-by-charge assemblies, assembly modes of which were modulated by the anionic building units. 相似文献
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146.
Frontispiece: Docking Strategy To Construct Thermostable,Single‐Crystalline,Hydrogen‐Bonded Organic Framework with High Surface Area
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147.
The normal dissolution rates, the slopes and the average velocities of dissolution steps of etch pits on the (111) face of a K-alum crystal, originating from dislocations with Burgers vector 110, were measured in relation to the surface undersaturations. From the mutual relations, it was shown that the dissolution was controlled by both diffusion and surface kinetic processes, although the contribution of the latter process was smaller than in the case of growth. It was also demonstrated that the normal dissolution rate was always larger than the growth rate. This is attributed to the fact that the slopes of growth hillocks are invariably smaller than those of etch pits. 相似文献
148.
Hayakawa I Ueda M Yamaura M Ikeda Y Suzuki Y Yoshizato K Kigoshi H 《Organic letters》2008,10(9):1859-1862
Second-generation total synthesis of haterumalide NA, a potent cytotoxic marine macrolide, was achieved by using B-alkyl Suzuki-Miyaura coupling and Nozaki-Hiyama-Kishi coupling as key steps (1.2% in 33 steps). Compared to our first-generation approach, the second-generation synthesis is much improved in the yield of key intermediate. 相似文献
149.
A variety of reactions such as substitution, dimerization, rhenium(I) metalation, and ring-opening reactions of N-fused porphyrin (NFP) and optical properties of the products are presented. Palladium-catalyzed cross-coupling reactions under Suzuki or Stille conditions afford aryl and arylethynyl-substituted NFPs (12, 14) and an ethynyl-bridged dimer (15) from 3-bromo-substituted NFP (3b) in 40-98% yields. Treatment of NFP with silver(I) trifluoroacetate in CHCl3 affords a dimer (22) linked at both C21-positions of the fused rings and its bis-Re(I) metal complex (24) is synthesized. X-ray structures of the 3-trifluoromethyl and 3-phenyl NFP derivatives (9e and 12a) reveal the three-center hydrogen bondings in the core. All the new NFP derivatives display unique absorption spectra, and particularly, ethyne-bridged NFP-dimer (15) shows a remarkable bathochromic shift into a near-infrared region showing an absorption band at 1020 nm with tailing up to 1100 nm. Moreover, alkoxide nucleophiles convert NFP into NCP derivatives by the cleavage of C-N bond in the fused ring, which is useful for the preparation of various C3-substituted NCPs and C21,C21′-linked NCP dimers from NFPs. 相似文献
150.
Taito Hashimoto Dr. Ryusei Oketani Masaki Nobuoka Prof. Dr. Shu Seki Prof. Dr. Ichiro Hisaki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202215836
Porous frameworks composed of non-stoichiometrically mixed multicomponent molecules attract much attention from a functional viewpoint. However, their designed preparation and precise structural characterization remain challenging. Herein, we demonstrate that cocrystallization of tetrakis(4-carboxyphenyl)hexahydropyrene and pyrene derivatives ( CP-Hp and CP-Py , respectively) yields non-stoichiometric mixed frameworks through networking via hydrogen bonding. The composition ratio of CP-Hp and CP-Py in the framework was determined by single crystalline X-ray crystallographic analysis, indicating that the mixed frameworks were formed over a wide range of composition ratios. Furthermore, microscopic Raman spectroscopy on the single crystal indicates that the components are not uniformly distributed such as ideal solid solution, but are done gradationally or inhomogeneously. 相似文献