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71.
Noriyuki Yoshii Yoshimichi Andoh Susumu Okazaki 《Journal of computational chemistry》2020,41(9):940-948
We derived a new expression for the electrostatic interaction of three-dimensional charge-neutral systems with two-dimensional periodic boundary conditions (slab geometry) using a fast multipole method (FMM). Contributions from all the image cells are expressed as a sum of real and reciprocal space terms, and a self-interaction term. The reciprocal space contribution consists of two parts: zero and nonzero terms of the absolute value of the reciprocal lattice vector. To test the new expressions, electrostatic interactions were calculated for a randomly placed charge distribution in a cubic box and liquid water produced by molecular dynamics calculation. The accuracy could be controlled by the degree of expansion of the FMM. In the present expression, the computational complexity of the electrostatic interaction of N-particle systems is order N, which is superior to that of the conventional two-dimensional periodic Ewald method for a slab geometry and the particle mesh Ewald method with a large empty space at an interface of the unit cell. © 2020 Wiley Periodicals, Inc. 相似文献
72.
Dr. Ming-Shui Yao Prof. Jia-Jia Zheng Ai-Qian Wu Prof. Gang Xu Sanjog S. Nagarkar Gen Zhang Masahiko Tsujimoto Prof. Shigeyoshi Sakaki Prof. Satoshi Horike Prof. Kenichi Otake Prof. Susumu Kitagawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(1):178-182
Single-ligand-based electronically conductive porous coordination polymers/metal–organic frameworks (EC-PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π-conjugated EC-MOF containing copper units with mixed trigonal ligands was developed: Cu3(HHTP)(THQ) (HHTP=2,3,6,7,10,11-hexahydrotriphenylene, THQ=tetrahydroxy-1,4-quinone). The modulated conductivity (σ≈2.53×10−5 S cm−1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g−1) of the Cu3(HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor. 相似文献
73.
Ming‐Shui Yao Jia‐Jia Zheng Ai‐Qian Wu Gang Xu Sanjog S. Nagarkar Gen Zhang Masahiko Tsujimoto Shigeyoshi Sakaki Satoshi Horike Kenichi Otake Susumu Kitagawa 《Angewandte Chemie (International ed. in English)》2020,59(1):172-176
Single‐ligand‐based electronically conductive porous coordination polymers/metal–organic frameworks (EC‐PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π‐conjugated EC‐MOF containing copper units with mixed trigonal ligands was developed: Cu3(HHTP)(THQ) (HHTP=2,3,6,7,10,11‐hexahydrotriphenylene, THQ=tetrahydroxy‐1,4‐quinone). The modulated conductivity (σ≈2.53×10?5 S cm?1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g?1) of the Cu3(HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor. 相似文献
74.
Koji Yamamoto Kazuki Higuchi Masahiro Ogawa Hiromitsu Sogawa Shigeki Kuwata Yoshihiro Hayashi Susumu Kawauchi Toshikazu Takata 《化学:亚洲杂志》2020,15(3):356-359
We synthesised palladium and platinum complexes possessing cyclic and acyclic pincer‐type polyaromatic ligands and investigated their structural effect on the catalysis. The pincer‐type bis(6‐arylpyridin‐2‐yl)benzene skeleton was constructed via Kröhnke pyridine synthesis under transition metal‐free conditions on gram‐scale quantity. Ligand structure significantly influenced catalytic activity toward the platinum‐catalysed hydrosilylation of diphenyl acetylenes, despite the ligand‐independence of the conformations and electronic properties of these complexes. 相似文献
75.
Yukiko Kamiya Fuminori Sato Keiji Murayama Atsuji Kodama Susumu Uchiyama Hiroyuki Asanuma 《化学:亚洲杂志》2020,15(8):1266-1271
Serinol nucleic acid (SNA) is a promising candidate for nucleic acid‐based molecular probes and drugs due to its high affinity for RNA. Our previous work revealed that incorporation of 2,6‐diaminpurine (D), which can form three hydrogen bonds with uracil, into SNA increases the melting temperature of SNA‐RNA duplexes. However, D incorporation into short self‐complementary regions of SNA promoted self‐dimerization and hindered hybridization with RNA. Here we synthesized a SNA monomer of 2‐thiouracil (sU), which was expected to inhibit base pairing with D by steric hindrance between sulfur and the amino group. To prepare the SNA containing D and sU in high yield, we customized the protecting groups on D and sU monomers that can be readily deprotected under acidic conditions. Incorporation of D and sU into SNA facilitated stable duplex formation with target RNA by suppressing the self‐hybridization of SNA and increasing the stability of the heteroduplex of SNA and its complementary RNA. Our results have important implications for the development of SNA‐based probes and nucleic acid drugs. 相似文献
76.
Sato S Komoto T Kanamaru Y Kawamoto N Okada T Kaiho T Mogi K Morimoto S Umehara N Koda T Miyashita A Sakamoto T Niino Y Oka T 《Chemical & pharmaceutical bulletin》2002,50(2):292-297
New muq-opioid receptor (MOR) agonists containing 4-hydroxypiperidine, piperidine and piperazine moieties were synthesized and evaluated to find a peripheral opioid analgesic. Among the synthesized compounds, 12-[1-[3-(N,N-dimethylcarbamoyl)-3,3-diphenylpropyl]-4-hydroxypiperidin-4-yl]phenoxy]acetic acid (8: SS620) having phenoxyacetic acid and 4-hydroxypiperidine moieties showed the highest agonist potency on the MOR in an isolated guinea-pig ileum preparation, and it also had selectivity to the human MOR expressed in Chinese hamster ovary (CHO)-K1 cells compared with the same types of delta- and kappa-opioid receptors (DOR and KOR). In addition, compound 8 showed a 10 times more potent MOR agonist activity than loperamide. Furthermore, compound 8 showed a peripheral analgesic activity in vivo screening on rat. 相似文献
77.
For the purpose of evaluating optimal fill level of starting materials in a high-shear mixer, discrete element method (DEM) simulation was conducted to visualize kinetic status between particles. The simulation results obtained by changing fill levels were used to determine solid fraction of particles, particle velocity, particle velocity vector, and kinetic energy and discuss the flow pattern. Optimal fill level was obtained from the information on these matters. It was pointed out that understanding the kinetic energy between particles in an agitating vessel was effective in determining the optimal fill level. Granulation experiment was conducted to validate the optimal fill level obtained by the simulation, confirming the good agreement between these two results. It was pointed out that determination of kinetic energy between particles through the simulation was effective in obtaining an index of the kinetic status of particles. Further, it was confirmed that the simulation could provide more information than conventional granulation experiments could provide and also helpful in optimizing the operating conditions. 相似文献
78.
Utilization of a metalloligand, ([Cu(2,4-pydca)2(H2O)].2Et3NH) (1) (2,4-pydca = pyridine-2,4-dicarboxylate), as a building unit provides a novel porous coordination polymer, ([ZnCu(2,4-pydca)2(H2O)3(DMF)].DMF)n (2), in which the Zn(II) ion at the node of the network acts as a linker and the Cu(II) ion in the channel wall is available for guest-coordination. 相似文献
79.
[reaction: see text] A combined system of boron trifluoride and molecular sieves is an efficient promoter for the carbonyl-ene reaction of alpha-methylsyrenes with paraformaldehyde. The coexistence of BF3 x OEt2 and molecular sieves 4A is essential for obtaining high yields of ene products. 相似文献
80.
Noda Susumu Imada Masahiro Chutinan Alongkarn Yamamoto Noritsugu 《Optical and Quantum Electronics》2002,34(8):723-736
Three-dimensional (3D) and two-dimensional (2D) photonic crystals based on III–V semiconductors are described. On the 3D photonic crystals, the development of complete photonic crystals at optical wavelengths and their applications to ultrasmall optical integrated circuits including 3D sharp bend waveguide are described. On the 2D photonic crystals, two-unique device and/or phenomena are demonstrated. 相似文献