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871.
872.
The application of non-thermal plasma generated by electron beam (EB) was investigated in laboratory scale to study decomposition of polycyclic aromatic hydrocarbons like naphthalene and acenaphthene in flue gas. PAH compounds were treated by EB with the dose up to 8 kGy in dry and humid base gas mixtures. Experimentally established G-values gained 1.66 and 3.72 mol/100 eV for NL and AC at the dose of 1 kGy. NL and AC removal was observed in dry base gas mixtures showing that the reaction with OH radical is not exclusive pathway to initialize PAH decomposition, however in the presence of water remarkably higher decomposition efficiency was observed. As by-products of NL decomposition were identified compounds containing one aromatic ring and oxygen atoms besides CO and CO2. It led to the conclusion that PAH decomposition process in humid flue gas can be regarded as multi-step oxidative de-aromatization analogical to its atmospheric chemistry.  相似文献   
873.
874.
875.
The fact that InN has a direct bandgap of 0.75eV enables InN-based nitrides devices to cover the wavelength range from UV region to 1.8mm, therefore, emerging as a new material system for optical communication applications.  相似文献   
876.
We have conducted a soft X-ray emission spectroscopy (SXES) and a photoemission electron microscopy (PEEM) study on the heat-treated Ti/4H–SiC system. This spectro-microscopy approach is an ideal surface and interface characterization techniques due to the non-destructive nature of SXES and the real-time surface imaging of PEEM.

The Si L2,3 and C K soft X-ray emission spectra, which reflect Si (s+d) states and C p states, respectively, revealed formations of Ti5Si3 and TiC in the reacted interfacial region of Ti (50 nm)/4H–SiC(0 0 0 1) sample.

The surface of the Ti films on 4H–SiC samples during heat-treatment up to 850 °C was investigated by PEEM. The variation in brightness in the image of the sample was attributed to the surface deoxidation in the early stage of the treatment and to the formation of reacted region at the later stage. The darkening of the surface could be attributed to the formation of TiC and/or excess C atoms that could have migrated to the surface.  相似文献   

877.
Poly(N-isopropylacrylamide) (PNIPAAm) has the sharpest phase transition of the class of thermo-sensitive N-alkyl acrylamide polymers. We developed a new method of HPLC using packing materials modified with cross-linked poly(N-isopropylacrylamide) (PNIPAAm) hydrogel. A temperature-responsive surface was prepared by polymerization of NIPAAm in the presence of a cross-linker on the silica support. The surface properties and functions of the stationary phases change in response to the external temperature. Therefore it easily changes the interaction of a solute with the surface with a constant aqueous mobile phase. A temperature-responsive elution behavior was observed on the separation of steroids and PTH-amino acids. The method is expected to be applicable to separation in the pharmaceutical and biomedical fields.  相似文献   
878.
Amphiphilic anthracene derivatives showed solvent-polarity-dependent fluorescence. Monomer emission and aggregation-induced emission (AIE) were observed in polar and non-polar organic solvents, respectively. AIE became predominant in aqueous solution in the case of hexafluorophosphate as a counter anion.  相似文献   
879.
An MT-sulfone group was converted to a trifluoromethyl group by treatment with IF(5) after an alkylation reaction. Therefore, an MT-sulfone anion can be used as a trifluoromethyl anion equivalent. The formal asymmetric Michael-addition of a trifluoromethyl anion to crotonaldehyde was also performed.  相似文献   
880.
Ru/C catalysts are active for the conversion of cellulose using 2-propanol or H(2) of 0.8 MPa as sources of hydrogen, whereas the Ru/Al(2)O(3) catalyst is inactive in both reactions, indicating that the Ru/C catalysts are remarkably effective for the cellulose conversion.  相似文献   
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