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81.
The removal of a mixture of painting solvents from waste air using a biofiltration process was evaluated in this project. The pollutants removed included hydrophobic (aromatic hydrocarbons) and hydrophilic (water soluble ketones and esters) compounds. A trickle bed reactor with a defined immobilized mixed culture on polyethylene Pall rings was utilized in this biodegradation study. The removal efficiencies (RE) of the individual groups of pollutants during loading experiments were determined. An increase of the aromatic hydrocarbons loading resulted in a drop of their REAROM with no effect on the RE value of ketones. The overloading of ketones caused a rapid drop in REAROM and a small drop in REKET. To achieve a restoration of the biocatalyst degradation properties after the increase in loading, an addition of phosphate to the aqueous medium was implemented which successfully restored the removal efficiency.  相似文献   
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Summary Samples of poly(ethylene terephthalate) (PET), poly(ethylene terephthalate-co-naphthalene-2,6-dicarboxylate) (PENT) and poly(ethylene naphthalene-2,6-dicarboxylate) (PEN), materials which find application in textile and packaging industry, have been investigated, with the aim to obtain narrow molecular weight fractions suitable for further characterization. Preliminary results concerning with the fractionation of gram-quantities of the polyesters are reported, using a method based on the fractional precipitation from a phenol/1,2,4-thrichlorobenzene solution of the polymer, using n-heptane as non-solvent. Obtained fractions have been characterized by intrinsic viscosity measurements and Gel Permeation Chromatography analysis.  相似文献   
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Updated results of massive life tests on CMOS are reported. The failure rate derived from laboratory conditions is extrapolated for long life use and compared with field results. Failure mechanism distribution is also reported.  相似文献   
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Degradation of n-Si/PtSi/(TiW)/Al Schottky contacts was observed for thermal treatments at 500–550°C. The barrier height decreases from 0.86 to about 0.60 V and then rises to 0.70 V. A striking correlation between metallurgical interdiffusion, growth of intermetallic compounds and electrical degradation is reported.  相似文献   
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Sufficient differential geometric conditions are given for the existence of global adaptive observers for a class of multi-output non-linear systems which are linear with respect to a vector of unknown constant parameters. They extend to multi-output systems earlier results on adaptive observers for single-output systems; they also extend to systems with unknown parameters results obtained previously on the existence of non-adaptive observers with linear error dynamics.  相似文献   
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Yellow-green controlled photorelease: probes click-linked to peptide-coated gold nanospheres by a triazole ring can be released in living cells under a focused 561 nm laser at low power. Photocleaving follows a three-photon event stimulated by the excitation of the localized surface plasmon resonance.  相似文献   
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