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11.
Sato H Tashiro K Shinmori H Osuka A Murata Y Komatsu K Aida T 《Journal of the American Chemical Society》2005,127(38):13086-13087
Upon binding with C60 and diamines, such as 4,4'-bipyridine (bpy) and N,N,N',N'-tetramethylhexane-1,6-diamine (TMHDA), cyclic host 1 possessing two electronically coupled binding sites displays negative homotropic cooperativity and positive heterotropic cooperativity, and their ternary mixtures preferentially form inclusion complexes with hetero-guest pairs 1 supersetC60*bpy and 1 supersetC60*TMHDA under appropriate conditions. Spectroscopic titration profiles in toluene at 20 degrees C demonstrated that the association constants (Kassoc) of C60 with monodiamine complexes 1 supersetbpy (2.8 x 105 M-1) and 1 supersetTMHDA (1.5 x 105 M-1) are 8.5 and 4.5 times greater than that of C60 with guest-free 1 (3.3 x 104 M-1), respectively. On the other hand, mono-C60 complex 1 supersetC60 was 6.1 times more accessible than guest-free 1 toward TMHDA. Absorption spectroscopy in the absence of 1 indicated no direct interaction between C60 and diamines. 相似文献
12.
Shuichi Naito Shigeru Aida Toshiki Kasahara Toshihiro Miyao 《Research on Chemical Intermediates》2006,32(3-4):279-290
In situ infrared spectroscopy was applied to elucidate the reaction mechanism of CO hydrogenation over Pd/CeO2. Instead of direct dissociation of CO, a new reaction pathway is proposed for methane formation, involving geminal dicarbonyl intermediates and (HCO)2(a) intermediates, which may be located on the surface of Pd covered with thin layers of reduced ceria (SMSI effect). Transformation of methane formation sites into methanol formation ones by the oxidation with water vapor formed during the CO?H2 reaction is proposed, which may be located on the Pd (111) planes adjacent to ceria support. 相似文献
13.
Susumu Takigawa Masanori Koshimizu Takio Noguchi Tsutomu Aida Seiichi Takami Tadafumi Adschiri Yutaka Fujimoto Akira Yoko Gimyeong Seong Takaaki Tomai Keisuke Asai 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(2):611-615
We synthesized liquid scintillators incorporating ZrO2 nanoparticles for application in neutrinoless double beta decay experiments. ZrO2 nanoparticles of less than 10 nm in size were synthesized with sub- and supercritical hydrothermal methods. The Zr concentrations in the liquid scintillators were determined to be up to 1.4 wt% with inductively coupled plasma analysis, and the liquid scintillators were transparent to scintillation. These results indicate that these methods are applicable for the preparation of liquid scintillators for neutrinoless double beta decay experiments. 相似文献
14.
Aida Avetisyan 《合成通讯》2013,43(17):2607-2609
A convenient procedure for the preparation of cerpegin is described. 相似文献
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Idris Zembouai Mustapha Kaci Stéphane Bruzaud Aida Benhamida Yves-Marie Corre Yves Grohens 《Polymer Testing》2013,32(5):842-851
The paper aims to study blend properties of biodegradable polymers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polylactide (PLA) prepared by melt mixing. Blend compositions based on PHBV/PLA were investigated according to the following weight ratios, i.e. 100/0, 75/25, 50/50, 25/75 and 0/100 wt%. The study showed through scanning electron microscopy (SEM) that blends of PHBV/PLA are not miscible. This is consistent with differential scanning calorimetry (DSC) data which indicate the presence of two distinct glass transition temperatures (Tg) and melting temperatures (Tm), attributed to the neat polymers, over all the range of blend compositions. Water and oxygen barrier properties of PHBV/PLA blends are significantly improved with increasing the PHBV content in the blend. Further, morphological analyzes indicated that increasing the PHBV content in the polymer blends results in increasing the PLA crystallinity due to the finely dispersed PHBV crystals acting as a filler and a nucleating agent for PLA. On the other hand, the addition of PLA to the blend results in a very impressive increase in the complex viscosity of PHBV. Moreover, the rheological data showed that, excluding the specific behavior of the neat polymers at low frequencies, i.e. less than 0.1 Hz, the complex viscosity of PHBV/PLA blends fits the mixing law well. 相似文献
20.
T. Umecky T. Takamuku T. Aida T. Makino T. Aizawa M. Kanakubo 《Journal of solution chemistry》2014,43(9-10):1539-1549
2H and 17O NMR relaxation times, T 1(2H) and T 1(17O), and 2H NMR chemical shifts, δ(2H), in CO2-saturated CD3OD and C2D5OD solutions were measured at 313.2 K over the pressure range up to ~6 MPa. The rotational correlation times, τ r, of the CD and OD axes within CD3OD and C2D5OD molecules and the CO axis within the CO2 molecule were determined from T 1(2H) and T 1(17O), and the magnetic susceptibility-corrected chemical shifts, δ corr, were derived from δ(2H). The differences in τ r and δ corr observed between the two alcohol systems: τ r and δ corr of OD in C2D5OD, decreased rapidly with increasing CO2 concentration, while those of OD in CD3OD remained almost unchanged at mole fractions of CO2, \( x_{\text CO_{2}} \) , lower than ~0.25 and then slightly decreased at higher \( x_{\text CO_{2}} \) . The hydrogen bonding structure in C2D5OD was found to be gradually broken down by CO2 dissolution. On the other hand, in CD3OD, it has been revealed that the hydrogen bonding structure can persist at \( x_{\text CO_{2}} \) < ~0.25 but then collapses at higher \( x_{\text CO_{2}} \) . 相似文献