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941.
Junhong Ha Shin-ichi Nakagiri Hiroki Tanabe 《Journal of Mathematical Analysis and Applications》2005,310(2):518-532
In this paper we establish the strong Gâteaux differentiability of maps from the set of initial values and forcing terms into the set of solutions for semilinear second-order evolution equations. 相似文献
942.
Takahiko Nojima Kenichi Yamashita Atsuko Takagi Makoto Takagi Yasuyuki Ikeda Hiroki Kondo Shigeori Takenaka 《Analytical sciences》2003,19(1):79-83
A ferrocenylnaphthalene diimide-based electrochemical hybridization assay (FND-EHA) was applied to the direct detection of a C-to-G transition in a codon (TCA) for Ser-447 of the human lipoprotein lipase (LPL) gene, which resulted in the termination of the LPL protein there. Either one of two 13-meric oligonucleotide probes, S447 WT and S447X MT, representing sequences complementary to those of the wild type (WT) and mutated (MT) forms, was immobilized on a gold electrode, followed by hybridization with chromosomal DNA extracted from human leukocytes under the condition in which both WT- and MT-type sequences can form a duplex. These two electrodes were soaked in an electrolyte containing FND under a condition [0.1 M HOAc/KOAc (pH 5.6) containing 0.1 KCl and 0.05 mM FND at 40 degrees C], in which only the MT duplex could undergo dissociation. FND was concentrated in proportion to the amount of the duplex formed on the electrode to give rise to a current signal. The electrochemical signal ratios obtained for WT/WT, WT/MT and MT/MT were close to the theoretical 2:1:0 with the S447 WT-modified electrode, and was again close to 0:1:2 with the S447X MT-modified one. 相似文献
943.
The room temperature structure of KOCN has been successfully refined in space group I4/mcm. The OCN anion is disordered through 180° head-tail flipping and the positional coordinates and displacement parameters could not be separated for the N and O end atoms. The displacement parameters are compared for isomorphous KOCN, KN3 and KSCN. 相似文献
944.
Hiroki Ohara Satoshi Sasaki Yukiko Konoike Takeshi Toyoda Kouji Yamawaki Masahiko Tanaka 《Physica B: Condensed Matter》2004,350(4):353-365
Synchrotron X-ray diffraction study for single crystals of Eu3S4 has revealed that a Th3P4-type
structure transforms to a charge-ordered
one at Tc=188.5 K. The crystal structures of Eu3S4 at T=300, 180 and 160 K were determined in the least-squares refinements with the Mo K intensity data. The valence-difference contrast method was applied at the LII absorption edge of Eu, utilizing a large difference in anomalous scattering factors between Eu2+ and Eu3+. The cation distribution of Eu2+ and Eu3+ was determined by crystal-structure analyses based on the intensity data collected at two wavelengths of λ=1.6312 and 1.6298 Å.The least-squares structural refinements suggest that the most plausible atomic arrangement is [Eu3+]4a[Eu2+Eu3+]8dS4. The charge-ordering scheme is that a half of Eu3+ ions occupy the whole 4a sites in the
crystal structure, while the remaining half of Eu3+ ions mix with Eu2+ in the 8d sites. The scheme is also supported by the energy dependence of Bragg intensities for 400 and 004 reflections. 相似文献
945.
Mitsuhiko Morisue Hiroki Fukui Masaki Shimizu Kenichi Inoshita Yasuhiro Morisaki Yoshiki Chujo 《Tetrahedron letters》2014
A novel binuclear phthalocyanine tweezers, in which two zinc-phthalocyanine rings are linked to an optically active binaphthyl group through triazolyl linkages, was self-cyclized through triazolyl-to-zinc coordination bonds. An axially chiral S-binaphthyl group induced planar chirality in a slipped-cofacial stack of phthalocyanine moieties, and therefore displayed fluorescence with a good quantum yield (ΦF = 0.23) and circularly polarized luminescence with a moderate intensity of dissymmetry factor (glum = −4 × 10−4) in the near-infrared wavelength region. 相似文献
946.
Adenosine 3′,5′-cyclic monophosphorodithioate (cAMPS2), which has two exocyclic sulfurs directly attached to phosphorus, was synthesized from adenosine phosphoramidite by intramolecular cyclization employing the phosphotriester method as a key step. 相似文献
947.
Dr. Yasufumi Takahashi Dr. Yu Kobayashi Dr. Ziqian Wang Dr. Yoshikazu Ito Masato Ota Dr. Hiroki Ida Dr. Akichika Kumatani Dr. Keisuke Miyazawa Prof. Takeshi Fujita Prof. Hitoshi Shiku Yuri E. Korchev Dr. Yasumitsu Miyata Prof. Takeshi Fukuma Prof. Mingwei Chen Prof. Tomokazu Matsue 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3629-3636
High-resolution scanning electrochemical cell microscopy (SECCM) is used to image and quantitatively analyze the hydrogen evolution reaction (HER) catalytically active sites of 1H-MoS2 nanosheets, MoS2, and WS2 heteronanosheets. Using a 20 nm radius nanopipette and hopping mode scanning, the resolution of SECCM was beyond the optical microscopy limit and visualized a small triangular MoS2 nanosheet with a side length of ca. 130 nm. The electrochemical cell provides local cyclic voltammograms with a nanoscale spatial resolution for visualizing HER active sites as electrochemical images. The HER activity difference of edge, terrace, and heterojunction of MoS2 and WS2 were revealed. The SECCM imaging directly visualized the relationship of HER activity and number of MoS2 nanosheet layers and unveiled the heterogeneous aging state of MoS2 nanosheets. SECCM can be used for improving local HER activities by producing sulfur vacancies using electrochemical reaction at the selected region. 相似文献
948.
Hiroki Matsubara Baku Ushijima Bruce M. Law Takanori Takiue Makoto Aratono 《Advances in colloid and interface science》2014
Alkane droplets on aqueous solutions of surfactants exhibit a first-order wetting transition as the concentration of surfactant is increased. The low-concentration or “partial wetting” state corresponds to an oil lens in equilibrium with a two-dimensional dilute gas of oil and surfactant molecules. The high-concentration or “pseudo-partial wetting” state consists of an oil lens in equilibrium with a mixed monolayer of surfactant and oil. Depending on the combination of surfactant and oil, these mixed monolayers undergo a thermal phase transition upon cooling, either to a frozen mixed monolayer or to an unusual bilayer structure in which the upper leaflet is a solid layer of pure alkane with hexagonal packing and upright chains while the lower leaflet remains a disordered liquid-like mixed monolayer. Additionally, certain long-chain alkanes exhibit a surface freezing transition at the air–oil interface where the top monolayer of oil freezes above its melting point. In this review, we summarize our previous studies and discuss how these wetting and surface freezing transitions influence the line tension of oil lenses from both an experimental and theoretical perspective. 相似文献
949.
Sequence‐Specific DNA Alkylation Targeting for Kras Codon 13 Mutation by Pyrrole–Imidazole Polyamide seco‐CBI Conjugates 下载免费PDF全文
Rhys Dylan Taylor Sefan Asamitsu Tomohiro Takenaka Makoto Yamamoto Kaori Hashiya Yusuke Kawamoto Dr. Toshikazu Bando Prof. Dr. Hiroki Nagase Prof. Dr. Hiroshi Sugiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(5):1310-1317
Hairpin N‐methylpyrrole‐N‐methylimidazole polyamide seco‐CBI conjugates 2 – 6 were designed for synthesis by Fmoc solid‐phase synthesis, and their DNA‐alkylating activities against the Kras codon 13 mutation were compared by high‐resolution denaturing gel electrophoresis with 225 base pair (bp) DNA fragments. Conjugate 5 had high reactivity towards the Kras codon 13 mutation site, with alkylation occurring at the A of the sequence 5′‐ACGTCACC A ‐3′ (site 2), including minor 1 bp‐mismatch alkylation against wild type 5′‐ACG C CACC A ‐3′ (site 3). Conjugate 6 , which differs from conjugate 5 by exchanging one Py unit with a β unit, showed high selectivity but only weakly alkylated the A of 5′‐ACGTCACC A ‐3′ (site 2). The hairpin polyamide seco‐CBI conjugate 5 thus alkylates according to Dervan′s pairing rule with the pairing recognition which β/β pair targets T–A and A–T pairs. SPR and a computer‐minimized model suggest that 5 binds to the target sequence with high affinity in a hairpin conformation, allowing for efficient DNA alkylation. 相似文献
950.
Yuya Yoshii Dr. Norihisa Hoshino Dr. Takashi Takeda Hiroki Moritomo Prof. Jun Kawamata Prof. Takayoshi Nakamura Prof. Tomoyuki Akutagawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(49):16279-16285
Simple organic salts based on aniline‐derived cations and D ‐tartrate anions formed organogels and helical nanofibers. The organic salt (p‐fluoroanilinium)(D ‐tartrate) was found to generate an organogel despite the absence of a hydrophobic alkyl chain, whereas (p‐iodoanilinium)(D ‐tartrate) formed helical nanofibers in braided ropelike structures through a rolling‐up process. The helicity of these nanofibers could be reversed by changing the growth solvent. The driving forces responsible for the formation of the nanofibers were determined to be 1D O?H???O? hydrogen‐bonding interactions between D ‐tartrate anions and π stacking of anilinium cations, as well as steric hindrance between the hydrogen‐bonded chains. 相似文献