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排序方式: 共有273条查询结果,搜索用时 15 毫秒
101.
Aliakbar Dehno Khalaji Hossein Mighani Hamid Reza Bijanzadeh Kazuma Gotoh Hiroyuki Ishida 《Journal of chemical crystallography》2011,41(10):1515-1519
Abstract
New Schiff-base compound (E)-2-(2,5-dimethoxybenzylideneamino)phenol (1) was synthesized and characterized by elemental analyses, FT-IR and 1H-NMR spectroscopy and single crystal X-ray diffraction. Molecular orbital calculation has been carried out for 1 by using HF method at 6-31G basis set. The title compound 1 crystallizes in monoclinic system, space group C2/c, with a = 19.4581(13) ?, b = 9.5805(5) Ǻ, c = 13.8431(7) Ǻ, β = 93.471(2)°, V = 2575.9(3) Ǻ3 and Z = 8. In the crystal structure two molecules are stabilized by a pair of intermolecular O1–H1···N1i hydrogen bonds. The dimeric units are further linked via C6–H6···O3ii hydrogen bond. 相似文献102.
Yoshiki Nakata Kazuma Momoo Noriaki Miyanaga Takuya Hiromoto Kunio Tsuchida 《Applied Physics A: Materials Science & Processing》2013,110(1):173-177
In this paper,we fabricate a lateral phase change memory device composed of a Ge2Sb2Te5 nanowire (GST NW) fully confined in a tungsten electrode nanogap. A SiNx spacer is used not only as etch mask for the fabrication of the GST NW, but also as sacrificial layer for the lift-off process, which makes it feasible to fully confine the GST NW in the metal electrode nanogap. Electrical characterization shows that the device has unprecedentedly low threshold current and SET voltage of only 16 μA and 80 mV, respectively. 相似文献
103.
K Amaike K Muto J Yamaguchi K Itami 《Journal of the American Chemical Society》2012,134(33):13573-13576
A nickel-catalyzed decarbonylative C-H biaryl coupling of azoles and aryl esters is described. The newly developed catalytic system does not require the use of expensive metal catalysts or silver- or copper-based stoichiometric oxidants. We have successfully applied this new C-H arylation reaction to a convergent formal synthesis of muscoride A. 相似文献
104.
Xu Y Wang C Dong Y Li L Jang K Mawatari K Suga T Kitamori T 《Analytical and bioanalytical chemistry》2012,402(3):1011-1018
Owing to the well-established nanochannel fabrication technology in 2D nanoscales with high resolution, reproducibility, and
flexibility, glass is the leading, ideal, and unsubstitutable material for the fabrication of nanofluidic chips. However,
high temperature (~1,000 °C) and a vacuum condition are usually required in the conventional fusion bonding process, unfortunately
impeding the nanofluidic applications and even the development of the whole field of nanofluidics. We present a direct bonding
of fused silica glass nanofluidic chips at low temperature, around 200 °C in ambient air, through a two-step plasma surface
activation process which consists of an O2 reactive ion etching plasma treatment followed by a nitrogen microwave radical activation. The low-temperature bonded glass
nanofluidic chips not only had high bonding strength but also could work continuously without leakage during liquid introduction
driven by air pressure even at 450 kPa, a very high pressure which can meet the requirements of most nanofluidic operations.
Owing to the mild conditions required in the bonding process, the method has the potential to allow the integration of a range
of functional elements into nanofluidic chips during manufacture, which is nearly impossible in the conventional high-temperature
fusion bonding process. Therefore, we believe that the developed low-temperature bonding would be very useful and contribute
to the field of nanofluidics. 相似文献
105.
Kazuma Shimomoto Atsushi Kobayashi Kohei Ueno Jitsuo Ohta Masaharu Oshima Hiroshi Fujioka Hidetaka Amanai Satoru Nagao Hideyoshi Horie 《固体物理学:研究快报》2009,3(4):124-126
The authors have grown high‐quality m ‐plane In0.36Ga0.64N (1 00) films on ZnO (1 00) substrates at room temperature (RT) by pulsed laser deposition (PLD) and have investigated their structural properties. m ‐plane InGaN films grown on ZnO substrates at RT possess atomically flat surfaces with stepped and terraced structures, indicating that the film growth proceeds in a two‐dimensional mode. X‐ray diffraction measurements have revealed that the m ‐plane InGaN films grow without phase separation reactions at RT. The full‐width at half‐maximum values of the 1 00 X‐ray rocking curves of films with X‐ray incident azimuths perpendicular to the c ‐ and a‐axis are 88 arcsec and 78 arcsec, respectively. Reciprocal space‐mapping has revealed that a 50 nm thick m ‐plane In0.36Ga0.64N film grows coherently on the ZnO substrate, which can probably explain the low defect density that is observed in the film. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
106.
Erica Sogo Siqi Zhou Haruna Haeiwa Reiko Takeda Kazuma Okazaki Marie Sekita Takuya Yamamoto Mikio Yamano Kazuichi Sakamoto 《Molecules (Basel, Switzerland)》2021,26(15)
Amber—the fossilized resin of trees—is rich in terpenoids and rosin acids. The physiological effects, such as antipyretic, sedative, and anti-inflammatory, were used in traditional medicine. This study aims to clarify the physiological effects of amber extract on lipid metabolism in mouse 3T3-L1 cells. Mature adipocytes are used to evaluate the effect of amber extract on lipolysis by measuring the triglyceride content, glucose uptake, glycerol release, and lipolysis-related gene expression. Our results show that the amount of triacylglycerol, which is stored in lipid droplets in mature adipocytes, decreases following 96 h of treatment with different concentrations of amber extract. Amber extract treatment also decreases glucose uptake and increases the release of glycerol from the cells. Moreover, amber extract increases the expression of lipolysis-related genes encoding perilipin and hormone-sensitive lipase (HSL) and promotes the activity of HSL (by increasing HSL phosphorylation). Amber extract treatment also regulates the expression of other adipocytokines in mature adipocytes, such as adiponectin and leptin. Overall, our results indicate that amber extract increases the expression of lipolysis-related genes to induce lipolysis in 3T3-L1 cells, highlighting its potential for treating various obesity-related diseases. 相似文献
107.
Chi Zhang Emiko Kazuma Yousoo Kim 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):17900-17908
Dehalogenative cycloaddition reaction is a powerful strategy to generate new ring scaffolds with π‐conjugated features on a surface, and thus holds great promise toward atomically precise electronic devices or nanomaterials. The ortho‐dihalo substitution provides a good strategy to realize cycloaddition. However, the limited understanding of intermediate states involved hinders mechanistic exploration for further precise design and optimization of reaction products. Now, the evolutions of competing surface‐stabilized radicals and organometallic intermediates in real space were visualized toward the formation of dominant conjugated four‐membered ring connections. From the interplay of scanning tunneling microscopy and density functional theory calculations, the stepwise metal‐mediated dehalogenative cycloaddition pathway is elucidated both experimentally and theoretically. The results provide fundamental insights into the intermediate states involved in on‐surface synthesis. 相似文献
108.
109.
Enantiomeric purities of axially chiral biaryls with hydroxyl, amino, and carboxyl groups can be easily determined by pmr spectra using MTPA derivatives and shift reagent. 相似文献
110.