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161.
Shinya Yamanaka Atsuko Shimosaka Yoshiyuki Shirakawa Jusuke Hidaka 《Journal of nanoparticle research》2010,12(3):831-839
Molecular dynamics simulations of supersaturated aqueous NaCl solution including the Pt(100) or NaCl(100) crystal surfaces
have been performed at an average temperature of 298 K. The behavior of the NaCl cluster produced in the solution have been
studied through the consideration of the water dielectric property near the crystalline surfaces for understanding the role
of crystal growth on the surface. The surfaces in the solutions greatly influence heterogeneous nucleation in crystallization
process. Density profile of the supersaturated solution and polarization of water molecules was calculated in order to describe
the effect of the surfaces on the solution structure at the solid–liquid interfaces. The formation levels of NaCl clusters
heavily depended on the water orientation at the interfaces. NaCl clusters were easily formed near the Pt(100) surface compared
with the NaCl(100) surface owing to a different construction of water molecules between the platinum and NaCl surface. 相似文献
162.
Yamamoto T Fukushima T Yamamoto Y Kosaka A Jin W Ishii N Aida T 《Journal of the American Chemical Society》2006,128(44):14337-14340
Newly designed norbornene-appended hexabenzocoronene 1 self-assembles, upon diffusion of an Et(2)O vapor into its CH(2)Cl(2) solution, to form either graphitic nanocoils or nanotubes, depending on the self-assembling conditions. The coiled assembly, selectively formed at 15 degrees C, is a kinetic intermediate for the tubular assembly and transforms into nanotubes on standing at 25 degrees C. However, post-ring-opening metathesis polymerization of the norbornene pendants of 1 enhances the thermal stability of the coiled assembly as well as the tubular one and disables a thermodynamic coil-to-tube transition. The polymerized nanocoils show an electroconductivity of 1 x 10(-)(4) S cm(-)(1) upon doping with I(2), while the nonpolymerized nanocoils are disrupted upon being doped. 相似文献
163.
A cytidine 5'-monophosphate (CMP)-sialic acid analogue carrying a fluorescent reporter group, an inhibitor of sialyltransferase, was synthesised in order to investigate glycan synthesis events in cells. The compound was found to be a substrate of a CMP-sialic acid transporter, and specific Golgi vesicles were visualised in the cells. 相似文献
164.
Theerayuth Plirdpring Ken Kurosaki Atsuko Kosuga Manabu Ishimaru Yuji Ohishi Hiroaki Muta Shinsuke Yamanaka 《固体物理学:研究快报》2012,6(4):154-156
Cu2Ga4Te7 has recently been reported to have a relatively high thermoelectric (TE) figure of merit (ZT). However, the TE properties of Cu2In4Te7, which has the same defect zinc‐blende structure as Cu2Ga4Te7, have been hardly investigated. Here, we demonstrate that Cu2In4Te7 has relatively high ZT values that are similar to those of Cu2Ga4Te7. High‐density polycrystalline bulk samples of Cu2In4Te7 were prepared and their electrical resistivity (?), Seebeck coefficient (S), and thermal conductivity (κ) were measured. Cu2In4Te7 has a maximum ZT of 0.3 at 700 K, with ?, S, and κ values of 62.1 × 10–5 Ω m, 394 μV K–1, and 0.61 W m–1 K–1, respectively. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
165.
Yukiko Maekawa Makiko Sugiura Atsuko Takeuchi Koji Tomoo Toshimasa Ishida Miyoko Kamigauchi 《Helvetica chimica acta》2010,93(5):991-998
The Advanced Glycation End Products (AGEs) are the causative substances of lifestyle‐habit illness. To elucidate the glycation mechanism of the protein, the reaction of lysozyme with D ‐glucose was analyzed by the fluorescence, TOF‐MS, and 13C‐NMR spectroscopy under the physiological condition. The fluorescence intensity of lysozyme in the glycation solution increased proportionally with a reaction time of ten weeks. The MALDI‐TOF‐MS spectra of the reaction solution after two weeks showed a peak at m/z 15066, which indicated the presence of a larger molecule than the native lysozyme (m/z 14331), and new peaks at m/z 30105 (dimer) and 45000 (trimer) were also observed. The spectral analysis supported the assumption of a continuous glycation reaction of D ‐glucose with lysozyme and a 30% transformation of lysozyme to the dimeric form during ten weeks. The 13C‐NMR spectra of lysozyme showed six [13C]‐labeled signals by the glycation reaction with [13C]‐glucose after two weeks of reaction. The combined analysis of TOF‐MS and 13C‐NMR spectra uncovered that first products of the glycation reaction of lysozyme with D ‐glucose can be observed already three hours after starting the reaction and that nine D ‐glucose units are attached during ten weeks at 37°. 相似文献
166.
Lu L Eychmüller A Kobayashi A Hirano Y Yoshida K Kikkawa Y Tawa K Ozaki Y 《Langmuir : the ACS journal of surfaces and colloids》2006,22(6):2605-2609
This article reports the designed preparation of two different kinds of novel porous metal nanostructured films, namely, an ordered macroporous Au/Ag nanostructured film and an ordered hollow Au/Ag nanostructured film. Different from previous reports, the presently proposed method can be conveniently used to control film structures by simply varying the experimental conditions. The morphology of these films has been characterized by scanning electron microscopy (SEM), and their performance as surface-enhanced Raman scattering (SERS) substrates has been evaluated by using rhodamine 6G (R6G) as a probe molecule. We show that such porous nanostructured films consisting of larger interconnected aggregates are highly desirable as SERS substrates in terms of high Raman intensity enhancement, excellent stability, and reproducibility. The interconnected nanostructured aggregate, long-range ordering porosity, and nanoscale roughness are important factors responsible for this large SERS enhancement ability. 相似文献
167.
Akilov OE Kosaka S O'Riordan K Song X Sherwood M Flotte TJ Foley JW Hasan T 《Chemistry & biology》2006,13(8):839-847
Photodynamic therapy (PDT) is emerging as a potential therapeutic modality in the clinical management of cutaneous leishmaniasis (CL). In order to establish a rationale for effective PDT of CL, we investigated the impact of the molecular charge and structure of photosensitizers on the parasitic phototoxic response. Two photosensitizers from the benzophenoxazine family that bear an overall cationic charge and two anionic porphyrinoid molecules were evaluated. The photodynamic activity of the photosensitizers decreases in the following order: EtNBSe > EtNBS > BpD > PpIX. The studies suggest that compared to hydrophobic anionic photosensitizers, the hydrophilic cationic benzophenoxazine analogs provide high effectiveness of PDT possibly due to (1) their strong attraction to the negatively charged parasitic membrane, (2) their hydrophilicity, (3) their high singlet oxygen quantum yield, and (4) their efficacy in targeting intracellular organelles. 相似文献
168.
The adsorption and photodecomposition of seven kinds of amino acids on a TiO2 surface were investigated by zeta potential measurements and 1H NMR spectroscopy in TiO2 aqueous suspension systems. The decomposition rates increased in the order of Phe < Ala < Asp < Trp < Asn < His < Ser. For Phe, Trp, Asn, His, and Ser, the isoelectric point (IEP) of TiO2 shifted to a lower pH with increasing decomposition rates upon adsorption on TiO2, suggesting that the effective adsorption and photocatalytic sites for these amino acids should be the basic terminal OH on the solid surface. Since the amino acids that decomposed faster than the others contain -OH (Ser), -NH (Trp, His), or -NH2 (Asn) in their side chain, they are considered to interact with the basic terminal OH groups more preferably by the side chain and are vulnerable to photocatalytic oxidation. On the other hand, Ala interacts with the acidic bridged OH on TiO2 to cause an IEP shift to a higher pH. The correlation of the surface hydroxyl groups with the photocatalysis of amino acids was verified by the use of calcined TiO2 without surface hydroxyl groups. 相似文献
169.
Ethenylbenzothiazoles were synthesized by the Horner-Emmons reaction of benzothiazolylmethylphosphonate with aldehydes under phase transfer catalytic conditions in 60–71% yields. Not only aromatic but also aliphatic aldehydes gave the desired products under these mild conditions in 66–71% yields. 相似文献
170.