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161.
Phenol degradation was carried out in acidic aqueous solution on different crystal structures of PbO2 surfaces at room temperature. Phenol, benzoquinone and maleic acid concentrations were monitored during the electrolysis process. It was determined that β surfaces have higher performance than surfaces on phenol degradation. Then, the effect of crystallinities of pure β-PbO2 surfaces was investigated and found that higher crystallinity increased the efficiency of the phenol degradation process.  相似文献   
162.
S is called a δ-semigroup if the lattice of all congruences of S is a chain with respect to inclusion. In the literature there are lots of papers which investigate the δ-semigroups in special classes of semigroups ([1], [3], [5], [6], [10], [11], [12], [14],). In this paper we describe the RGC n -commutative δ-semigroups.  相似文献   
163.
The correlation between the surface cross-hatched morphology and the interfacial misfit dislocations in partially relaxed InGaAs/GaAs heterostructures was studied by means of atomic force microscopy and electron-beam induced current mode in a scanning electron microscope. A close correspondence between the misfit-dislocation network at the interface and the surface morphology shows that the cross-hatch development results primarily from the misfit-dislocation generation. Statistical analysis of the surface roughness reveals an anisotropy in strain relaxation of the epitaxial layers, which results from an asymmetry in the misfit-dislocation formation.  相似文献   
164.
We-m semigroups     
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166.
Nickel was electrodeposited on one side and chromium on the other side of a sheet of α-iron enriched (∼85%) with57Fe. The electrodeposited Ni and Cr contained oxygen and it could be separated by 500 keV xenon implantation. The separated oxygen formed an amorphous metal-oxide interphase at the interface of iron substrate and electrodeposited Ni or Cr.  相似文献   
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168.
The emission Mössbauer technique is used to study the chemical structure of the interphase formed between a cobalt substrate and a polyimide coating. The results are interpreted to indicate that the coating is bonded to the cobalt substrate by means of carboxylate bonds with Co2+ ions in the oxide film at the interface.  相似文献   
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170.
57Fe conversion electron Mössbauer spectroscopy, X-ray diffraction, electrochemical and magnetic measurements were used to study pulse electroplated Fe–P and Ni–Fe coatings. XRD and 57Fe CEMS measurements revealed the amorphous character of the novel pulse plated Fe–P alloys. CEM spectra indicated significant differences in the short range order and in the magnetic anisotropy between the Fe–P deposits pulse plated at medium long deposition time (t on?=?2 ms), with short relaxation time (t off?=?9 ms) and low current density (I p?=?0.05 Acm?2) or at short deposition time (t on?=?1 ms) with long relaxation time (t off?=?250 ms) and high current density (I p?=?1.0 Acm?2). The broad peaks centred around the fcc reflections in XRD of the pulse plated Ni-22 wt.% Fe deposit reflected a microcrystalline Ni–Fe alloy with a very fine, 5–8 nm, grain size. The CEM spectrum of the pulse plated Ni-22 wt.% Fe coating corresponded to a highly disordered solid solution alloy containing a minute amount of ferrihydrite. Extreme favourable soft magnetic properties were observed with these Ni–Fe and Fe–P pulse plated thin layers.  相似文献   
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