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81.
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
82.
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
83.
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
84.
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
85.
Copper(II) compounds {CuCA(phz)(H2O)2}n (H2CA = chloranilic acid, phz = phenazine) having a layer structure of -CuCA(H2O)2- polymer chains and phenazine were studied by 35Cl nuclear quadrupole resonance (NQR). The single NQR line observed at 35.635 MHz at 261.5 K increased to 35.918 MHz at 4.2 K. The degree of reduction of electric field gradient due to lattice vibrations was similar to that of chloranilic acid crystal. Temperature dependence of spin-lattice relaxation time, T1, of the 35Cl NQR signal below 20 K, between 20 and 210 K, and above 210 K, was explained by (1) a decrease of effective electron-spin density caused by antiferromagnetic interaction, (2) a magnetic interaction between Cl nuclear-spin and electron-spins on paramagnetic Cu(II) ions, and (3) an increasing contribution from reorientation of ligand molecules, respectively. The electron spin-exchange parameter ∣J∣ between the neighboring Cu(II) electrons was estimated to be 0.33 cm−1 from the T1 value of the range 20−210 K. Comparing this value with that of J = −1.84 cm−1 estimated from the magnetic susceptibility, it is suggested that the magnetic dipolar coupling with the electron spins on Cu(II) ions must be the principal mechanism for the 35Cl NQR spin-lattice relaxation of {CuCA(phz)(H2O)2}n but a delocalization of electron spin over the chloranilate ligand has to be taken into account. 相似文献
86.
In this paper we present theoretical analyses on an infrared (IR) spectrum of amorphous selenium. The system is described by a 216-atom-chain model, and a set of molecular-dynamics simulations is performed to generate vitreous structures and vibrational modes. To describe an electronic structure of the system we employ a complete neglect of differential overlap model parametrized by ab initio cluster calculations. An IR intensity is evaluated with the Berry-phase formula for an electronic polarization. The effect of the through-space electron transfer on the IR spectrum is studied by artificially changing the magnitude of matrix elements associated with the electron transfer between nonbonded atoms in the chain. We find that the through-space electron transfer leads to (i) the enhancement of the bending IR peak at 135 cm(-1) and (ii) the appearance of a new low-frequency peak around 50 cm(-1), thus resulting in a good agreement with the experiment. The mechanism is discussed by a simple dipole model. 相似文献
87.
88.
Haruka Ohsato Kazuma Kawauchi Prof. Shigeyuki Yamada Prof. Tsutomu Konno 《Chemical record (New York, N.Y.)》2023,23(9):e202300080
Organic molecules with fluoroalkylene scaffolds, especially a tetrafluoroethylene (CF2CF2) moiety, in their molecular structures exhibit unique biological activities, or can be applied to functional materials such as liquid crystals and light-emitting materials. Although several methods for the syntheses of CF2CF2-containing organic molecules have been reported to date, they have been limited to methods using explosives and fluorinating agents. Therefore, there is an urgent need to develop simple and efficient approaches to synthesize CF2CF2-containing organic molecules from readily available fluorinated substrates using carbon-carbon bond formation reactions. This personal account summarizes the simple and efficient transformation of functional groups at both ends of 4-bromo-3,3,4,4-tetrafluorobut-1-ene and discusses its synthetic applications to biologically active fluorinated sugars and functional materials, such as liquid crystals and light-emitting molecules. 相似文献
89.
90.
Dr. Toshio Nishino Dr. Colin J. Martin Hiroki Takeuchi Florence Lim Dr. Kazuma Yasuhara Yohan Gisbert Dr. Seifallah Abid Dr. Nathalie Saffon-Merceron Dr. Claire Kammerer Prof. Dr. Gwénaël Rapenne 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(52):12010-12018
The design and synthesis of a new family of nanocars is reported. To control their motion, we integrated a dipole which can be tuned thanks to strategic donor and acceptor substituents at the 5- and 15-positions of the porphyrin backbone. The two other meso positions are substituted with ethynyltriptycene moieties which are known to act as wheels. Full characterization of nine nanocars is presented as well as the electrochemistry of these push-pull molecules. DFT calculations allowed us to evaluate the magnitude of the dipoles and to understand the electrochemical behavior and how it is affected by the electron donating and accepting groups present. An X-ray crystal structure of one nanocar has also been obtained. 相似文献