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81.
82.
Degradation of aliphatic-aromatic copolyesters by bacteria that can degrade aliphatic polyesters 总被引:1,自引:0,他引:1
Toshiaki Nakajima-Kambe Fumie Ichihashi Satoshi Kato 《Polymer Degradation and Stability》2009,94(11):1901-1905
The degradation activities of bacteria that can degrade aliphatic polyesters on various aliphatic-aromatic copolyesters (PBSTIL, PBST, and Ecoflex™) were investigated. Among the bacteria examined, strain TB-71 showed the best degradation activity. An HPLC analysis of the degradation products revealed that PBST55 and Ecoflex™ are degraded into monomers by strain TB-71. In the case of PBSTIL, an unknown peak was detected by the HPLC analysis and was considered to be derived from water-soluble oligomers containing isophthalic acid segments. This finding seemed to be attributed to the chemical structure of the aromatic segments of the copolymers. 相似文献
83.
84.
Tomohito Kameda Saya Ito Toshiaki Yoshioka 《Journal of Dispersion Science and Technology》2017,38(7):1063-1066
We found that activated carbon effectively removed urea from solution and that urea adsorption onto activated carbon followed a pseudo-second-order kinetic model. We classified the urea adsorption on activated carbon as physical adsorption and found that it was best described by the Halsey adsorption isotherm, suggesting that the multilayer adsorption of urea molecules on the adsorption sites of activated carbon best characterized the adsorption system. The mechanism of adsorption of urea by activated carbon involved two steps. First, an amino (–NH2) group of urea interacted with a carbonyl (–C?O) group and a hydroxyl (?OH) group on the surface of activated carbon via dipole–dipole interactions. Next, the –C?O group of the urea molecule adsorbed to the activated carbon interacted with another –NH2 group from a second urea molecule, leading to multilayer adsorption. 相似文献
85.
Two-photon near-infrared excitation-responsive amino acid was developed. It was incorporated into a peptide, and focused near-infrared pulsed laser irradiation-induced peptide bond cleavage reaction at the C-terminal position of the photo-responsive amino acid was observed. 相似文献
86.
The reaction of 1-silylcyclopropyl anions with dichloromethyl methyl ether is described. The reaction with an excess amount of dichloromethyl methyl ether gives the corresponding cyclopropyl silyl ketones in low yields. On the other hand, the reaction under basic conditions proceeded smoothly to afford the corresponding cyclopropylidene derivatives, exclusively. The resulting cyclopropylidene compounds are subjected to hydrolysis or trapping with electrophiles easily to give the cyclopropyl silyl ketone derivatives in good yields. 相似文献
87.
Though preparation procedures of heterogeneous Ziegler‐Natta catalysts for propylene polymerization are sophisticated, it is uncertain whether the nature of the active sites is similar or different for different preparation procedures. In this study, the effects of preparation procedures on the nature of the active sites were investigated by stopped‐flow polymerization in combination with microstructure analysis of polymers. Both basic and advanced types of catalysts showed the same two kinds of isospecific active site, which indicated little influence of the preparation method on the active site structure. On the contrary, the ratios of the two kinds of isospecific sites were not the same, resulting in variation of average polymer properties.
88.
Toshiaki Kaminaka Miki Wadati 《Physics letters. A》2011,375(24):2460-2464
We study higher order solutions of Lieb-Liniger integral equation for a one-dimensional δ-function Bose gas. By use of the power series expansion method, the integral equation is solved and the correction terms which improve the Bogoliubov theory are calculated analytically in the weak coupling regime. Physical quantities such as the ground state energy and the chemical potential are represented by a dimensionless parameter γ=c/ρ, where c is the interaction strength and ρ is the number density of particles while the quasi-momentum distribution function is expressed in terms of a dimensionless parameter λ=c/K, where K is the cut-off momentum. 相似文献
89.
90.