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91.
Using the emulsion method, we measured the homogeneous nucleation temperature depression, DeltaT(f,hom), and equilibrium melting points depression, DeltaT(m), of various aqueous solutions and then calculated lambda for each solute using the linear relationship DeltaT(f,hom) = lambdaDeltaT(m). We defined lambda as the solute-specific supercooling capacity and examined its correlation with some known hydration characteristics. The results showed that lambda is correlated with D0, the self-diffusion coefficient of solute molecules in infinite dilution. 相似文献
92.
Synchronization phenomena in coupled circadian oscillators of plant leaves were investigated experimentally using bioluminescence technology for a clock gene. Analyzing the phase of circadian oscillation, the phase-wave propagations and the phase delay caused by the vein network were observed. We describe these phase dynamics using a two-layer model with coupled Stuart-Landau equations. Global synchronization of circadian oscillators in the leaf is also investigated. 相似文献
93.
meso,β‐Oligohaloporphyrins as Useful Synthetic Intermediates of Diphenylamine‐Fused Porphyrin and meso‐to‐meso β‐to‐β Doubly Butadiyne‐Bridged Diporphyrin
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Norihito Fukui Prof. Dr. Hideki Yorimitsu Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2015,54(21):6311-6314
The chlorination of β‐halo or β,β‐dihaloporphyrins with 2‐chloro‐1,3‐bis(methoxycarbonyl)guanidine (Palau′Chlor) proceeded selectively at the neighboring unsubstituted meso position to afford meso,β‐dihalo or meso,β,β‐trihaloporphyrins. Such oligohaloporphyrins are useful platforms for constructing more‐elaborate porphyrin‐based extended π systems. For example, meso‐chloro‐β,β‐diiodoporphyrin participated in an efficient single‐step synthesis of a diphenylamine‐fused porphyrin. In addition, meso‐chloro‐β‐iodoporphyrin was transformed in stepwise fashion into an efficiently conjugated meso‐to‐meso,β‐to‐β doubly butadiyne‐linked porphyrin dimer, a system which was previously difficult to access without such haloporphyrin precursors. 相似文献
94.
Amphiphilic Organic–Inorganic Hybrid Zeotype Aluminosilicate like a Nanoporous Crystallized Langmuir–Blodgett Film
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Dr. Takuji Ikeda Dr. Norihito Hiyoshi Dr. Shun‐ichi Matsuura Dr. Tetsuya Kodaira Takuma Nakaoka Ami Irisa Miki Kawano Dr. Katsutoshi Yamamoto 《Angewandte Chemie (International ed. in English)》2015,54(27):7994-7998
A new organic–inorganic hybrid zeotype compound with amphiphilic one‐dimensional nanopore and aluminosilicate composition was developed. The framework structure is composed of double aluminosilicate layers and 12‐ring nanopores; a hydrophilic layer pillared by Q2 silicon atom species and a lipophilic layer pillared by phenylene groups are alternately stacked, and 12‐ring nanopores perpendicularly penetrate the layers. The framework topology looks similar to that of an AFI‐type zeolite but possesses a quasi‐multidimensional pore structure consisting of a 12‐ring channel and intersecting small pores equivalent to 8‐rings. The hybrid material with alternately laminated lipophilic and hydrophilic nanospaces can be assumed as a crystallized Langmuir–Blodgett film. It demonstrates microporous adsorption for both hydrophilic and lipophilic adsorptives, and its outer surface tightly adsorbs lysozyme whose molecular size is much larger than its micropore opening. Our results suggest the possibility of designing porous adsorbent with high amphipathicity. 相似文献
95.
Kunimitsu Kataoka Norihito Kijima Hiroshi Hayakawa Akira Iyo Ken-ichi Ohshima Junji Akimoto 《Journal of solid state chemistry》2011,184(11):3117-3120
Polycrystalline sample of the reduced barium titanate Ba2Ti13O22 was synthesized by solid state reaction at 1523 K in Ar atmosphere for the first time. The Rietveld refinement using the powder X-ray diffraction data confirmed the sample to be main phase of Ba2Ti13O22 having the orthorhombic crystal system, space group Bmab and the lattice parameters of a=11.67058(11) Å, b=14.12020(13) Å and c=10.06121(9) Å, and V=1657.995(20) Å3. The valence state of Ti was evaluated by both the Ti–O bond distance analysis and the Ti K-edge XANES analysis. The magnetic susceptibility was nearly temperature independent in the range of 60–300 K, suggesting the Van Vleck Paramagnetism. The electrical conductivity at 300 K is approximately 320.50 S/cm, and a semiconducting behavior was observed below room temperature. The Seebeck coefficient showed a negative value of −1.25 μV/K at 300 K, indicating n-type behavior. These facts were confirmed by the results of the present theoretical calculations by the FLAPW method. 相似文献
96.
Temperature imaging of water in a microchannel using thermal sensitivity of near-infrared absorption
This paper presents a remote and preparation-free method of temperature imaging of aqueous solutions in microchannels of microfluidic chips. The principle of this method is based on the temperature dependency of the near-infrared (NIR) absorption band (ν(2) + ν(3) band) of water. Temperature images were constructed from absorbances in a narrow wavelength range including 1908 nm, the most sensitive to temperature in the band, measured by using an NIR camera and an optical narrow-bandpass filter. Calculation and calibration results demonstrated a linear relationship between the absorption coefficient and temperature with a temperature coefficient of 1.5 × 10(-2) K(-1) mm(-1). Temperature images of 50 μm thick water in a Y-shaped PDMS microchannel locally heated by a neighboring hot wire were obtained, in which thermal diffusion processes in the microchip were visualized. Temperature resolution was estimated to be approximately 0.2 K according to the temperature coefficient and noise level. 相似文献
97.
Ishii N Mamiya J Ikeda T Winnik FM 《Chemical communications (Cambridge, England)》2011,47(4):1267-1269
Irradiation at room temperature of α,ω-di-[4-cyanophenyl-4'-(6-hexyloxy)-azobenzene]-poly-(N-isopropylacrylamide) (Az(2)-PNIPAM) solutions in water/1,4-dioxane (6 mol% dioxane) reversibly converts a turbid suspension into a clear solution, demonstrating for the first time that cononsolvency of PNIPAM in mixed aqueous solvents in synergy with preferential chromophore solvation can act as actuators of responsive systems. 相似文献
98.
Chiral recognition abilities of the title host for (R)- and (S)-α-methyl-4-nitrobenzylamine were examined in the ground and excited states to give a relative affinity (K(R)/K(S)) of 2.16 by spectral titration and a relative rate constant (k(R)/k(S)) of 2.23 by fluorescence quenching, revealing that the quenching process is static and not enantiodifferentiating. 相似文献
99.
In this paper, we find a basis for the space S k (?? 0(4)) of cusp forms of even weight k for the congruence subgroup ?? 0(4) in terms of Eisenstein series. As an application, we obtain formulas for r 4s (n), the number of ways to represent a nonnegative integer n as a sum of 4s integral squares. 相似文献
100.
Material and electronic properties of Ni–Nb–Zr–H glassy alloys were investigated as a function of the rotating wheel speed in the amorphous ribbon-preparation method. Increase in density and amorphous colony size indicates that the degree of amorphousness increases with increase in the rotating speed. Supercooling, which reached by rotating wheel speed of 10,000 rpm (104.7-m/s), of the molten alloy produces a ballistic conductor with electrical conductivity of about 0.1 nΩ cm (× 10? 9 Ω cm, 0.01% of silver (1.62 μΩ cm)) for (Ni0.36Nb0.24Zr0.40)94.6 H5.4 glassy alloy and a room-temperature discrete Coulomb oscillation for (Ni0.36Nb0.24Zr0.40)91.6H8.4 glassy alloy. The increase in degree of amorphousness by supercooling induces uniformity of cluster morphology. 相似文献