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11.
No difference in the actual gel points was substantially observed among three isomeric diallyl phthalates such as diallyl phthalate (DAP), diallyl isophthalate, and diallyl terephthalate (DAT); this interesting gelation behavior was discussed further in terms of the correlation between gelation and the difference in cyclization modes, and also, the difference in reactivity between the uncyclized and cyclized radicals for cross‐linking. In the present work, we tried to extend the preceding discussion to the polymerization of triallyl trimellitate (TAT) because the molecular structure of TAT is presumed to essentially involve the characteristics of three isomeric diallyl phthalates and, therefore, the enhanced gelation was expected in TAT polymerization. However, no enhancement of gelation was observed. For a full understanding of the gelation in multiallyl cross‐linking polymerization, we explored further the polymerizations of DAP, DAT, and TAT, especially focusing on the characterization of resultant network polymer precursors (NPPs) using SEC‐MALLS‐viscometry providing the correlation of [η] versus Mw of fractionated samples. Notably, the structure of NPP consisting of oligomeric primary polymer chains generated from specific allyl polymerization would become core‐shell type dendritic with the progress of polymerization. The correlation between delayed gelation and decreased reactivity of dendritic NPP for intermolecular cross‐linking is discussed. Conclusively, the reactivity for intermolecular cross‐linking between NPPs decreased with the progress of polymerization leading to a delayed gelation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2871–2881, 2009  相似文献   
12.
Lysocin E, a macrocyclic peptide, exhibits potent antibacterial activity against methicillin‐resistant Staphylococcus aureus (MRSA) through a novel mechanism. The first total synthesis of lysocin E was achieved by applying a full solid‐phase strategy. The developed approach also provides rapid access to the enantiomeric, epimeric, and N‐demethylated analogues of lysocin E. Significantly, the antibacterial activity of the unnatural enantiomer was comparable to that of the natural isomer, suggesting the absence of chiral recognition in its mode of action.  相似文献   
13.
We show that there is a reduction of the magnetic transition strength at high momentum transfer due to core polarization. This accounts substantially for the observed reduction of 50% of the Jπ=12? and 14? transitions in 208Pb. The core polarization does not affect the shape of the high J form factors in the vicinity of their main peaks. However, a significant q-dependent effect is predicted for the ground state M1 moment of 207Pb.  相似文献   
14.
The electrochemical reduction of nitric oxide in the presence of the excess oxygen was reviewed. It was shown that the selectivity and activity of the cathodes is strongly dependent on the composition and on the microstructure of the cathode material. A concept of electrochemical reactor with multilayer electro-catalytic electrode was proposed and successfully designed in Advanced Manufacturing Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Nagoya, Japan. The typical values of current efficiency in such electrochemical reactors are of the order of 10–20% at gas composition: 1,000 ppm NO and 2% O2 balanced in He and at gas flow rate 50 ml/min. The value of current efficiency depends on the functional multi-layer electrode composition, structure, and operating temperature. Such electrochemical reactors show the value of NO/O2 selectivity (ν sel) higher than 5 (ν sel > 5) at intermediate temperature and up to ν sel = 25 at low temperature operation. It was shown that multilayer electro-catalytic electrode should consist at list from three main functional layers: cathode, electro-catalytic electrode, covering layer, in order to operate as an electrode with high selectivity.  相似文献   
15.
In an effort to improve and simplify refractive index sensors, we identified a basic operation mode at the critical angle. Sensitivity to the refractive index is higher than in standard surface plasmon resonance sensors, and we have been able to demonstrate analytically that it is virtually an unbounded value. We describe this approach and submit a complete analytical study demonstrating its unlimited sensing power. To test the approach, we constructed an economical and basic sensor. Despite its simplicity, we demonstrated the discrimination capability to be of the order of 10(-6), as far as we know close to the best sensitivity ever recorded. This detection method is generally applicable to any optical system and may pave the way for the next generation of optical sensing devices.  相似文献   
16.
There are few novel therapeutic options available for companion animals, and medications rely heavily on repurposed drugs developed for other species. Considering the diversity of species and breeds in companion animal medicine, comprehensive PK exposures in the companion animal patient is often lacking. The purpose of this paper was to assess the pharmacokinetics after oral and intravenous dosing in domesticated animal species (dogs, cats, and horses) of a novel soluble epoxide hydrolase inhibitor, EC1728, being developed for the treatment of pain in animals. Results: Intravenous and oral administration revealed that bioavailability was similar for dogs, and horses (42 and 50% F) but lower in mice and cats (34 and 8%, respectively). Additionally, clearance was similar between cats and mice, but >2× faster in cats vs. dogs and horses. Efficacy with EC1728 has been demonstrated in mice, dogs, and horses, and despite the rapid clearance of EC1728 in cats, analgesic efficacy was demonstrated in an acute pain model after intravenous but not oral dosing. Conclusion: These results demonstrate that exposures across species can vary, and investigation of therapeutic exposures in target species is needed to provide adequate care that addresses efficacy and avoids toxicity.  相似文献   
17.
A new multilayered electrochemical cell for NOx decomposition was prepared. The cell demonstrated good characteristics at moderate temperatures (350–450 °C) and possessed much higher selectivity with respect to NOx decomposition than previous one. It was found that the “crossover” process from high selective regime to the normal regime depends on the chemical composition of the catalytic electrode.  相似文献   
18.
The oxidative intramolecular coupling reaction of phenol ether derivatives (nonphenolic derivatives) on treatment with a novel combination of a hypervalent iodine(III) reagent, phenyliodine bis(trifluoroacetate) (PIFA), and heteropoly acid (HPA) was studied. Biaryl compounds were obtained in excellent yields on treatment of highly substituted phenol ethers. On the other hand, spirodienones were specifically formed when one of the preferred arylic coupling sites was substituted with a methoxy group in the para position.  相似文献   
19.
A poly(N-isopropylacrylamide) (PNIPAAm) gel cross-linked with quaternized aminoalkyls was designed. A novel recyclable system based on the external solvent-responsive oil-absorption/elution transition ability of the PNIPAAm gel matrix was then developed.  相似文献   
20.
Both positive-energy and weakly-bound one-particle levels for neutrons in Y20 deformed Woods-Saxon potentials are examined in comparison with those in spherical Woods-Saxon potentials. While s1/2 levels play a unique role in spherical drip-line nuclei, the Ωπ = 1/2+ levels in Y20 deformed potentials, which always contain some amount of s1/2 component, exhibit an important role in deformed drip-line nuclei. As the potential strength becomes weaker, some weakly-bound Ωπ = 1/2+ levels continue to the positive-energy region as one-particle resonant levels, while others have no such continuation. Among an infinite number of one-particle levels at a given positive-energy and in a given deformed potential, only some selected levels expressed in terms of eigenphase are found to be important in the pair-correlated ground state of neutron-drip-line nuclei.  相似文献   
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