Pilot-scale test on electron beam treatment of municipal solid waste flue gas with spraying slaked-lime slurry

Simultaneous removal of NO_x, SO₂ and HCl in flue gas of a municipal solid waste incinerator was studied by using electron beam irradiation technology. The flue gas around of 1000 Nm³/h was led to a spray-dryer-type reactor from an inlet of ESP of the municipal waste incinerator by spraying slaked-lime slurry with one or more stoichiometic amount of the pollutants, concentrations of HCl (400 ppm) and SO₂ (50 ppm) decreased almost completely, while concentrations of NO_x (100 ppm) were markedly decreased to about 20 ppm by electron beam irradiation with a dose of 10 kGy at 150°C under spraying slaked-time slurry of two stoichiometric amounts. The removal of NO_x was improved by increasing the dose and the amount of spraying slaked-time slurry, and by lowering the irradiation temperature.     

ESR study on the photosensitized decomposition of polyethylene

Several aromatic compounds were added to low-density polyethylene to determine their effects on the photodegradation of polyethylene. It was shown that some aromatic compounds indeed sensitize the hydrogen abstraction of the allylic hydrogen of unsaturated groups contained in polyethylene as an improper bond. The mechanism of photosensitization was investigated by an ESR method. It was found that the higher photoexcited triplet state of an aromatic molecule produced by the biphotonic ultraviolet light absorption transfers its excess energy to the unsaturated bond to excite it, and the excited unsaturated group releases its allylic hydrogen atom, giving an allylic radical.     

Ruthenium-catalyzed oxidation of alkanes with tert-butyl hydroperoxide and peracetic acid

The ruthenium-catalyzed oxidation of alkanes with tert-butyl hydroperoxide and peracetic acid gives the corresponding ketones and alcohols highly efficiently at room temperature. The former catalytic system, RuCl(2)(PPh(3))(3)-t-BuOOH, is preferable to the oxidation of alkylated arenes to give aryl ketones. The latter system, Ru/C-CH(3)CO(3)H, is suitable especially for the synthesis of ketones and alcohols from alkanes. The ruthenium-catalyzed oxidation of cyclohexane with CH(3)CO(3)H in trifluoroacetic acid/CH(2)Cl(2) at room temperature gave cyclohexyl trifluoroacetate and cyclohexanone with 90% conversion and 90% selectivity (85:15). The mechanistic study indicates that these catalytic oxidations of hydrocarbons involve oxo-ruthenium species as key intermediates.     

Electron spin resonance study of poly-3,3-bis-(chloromethyl)oxetane irradiated with ultraviolet light

When poly-3,3-bis(chloromethyl)oxetane has been irradiated at ?196°C in a nitrogen atmosphere with ultraviolet light, a triplet spectrum is observed. After warming the sample, both a doublet and a singlet ESR spectra are observed. These spectra are attributed to and ? CH₂? O, respectively. The formation mechanism of these free radicals is discussed. It is concluded that the main process of radical formation is the dissociation of chemical bonds from the excited state of the polymer produced through the energy absorption by irregular groups acting as sensitizers. In the presence of oxygen, the radical yield at ?196°C is greater than that in nitrogen atmosphere. This is attributed to the extra absorption of light by the charge transfer complexes of polymers with oxygen molecules. It is also proposed that participation of a charge transfer complex in photooxidation of ether is important in the primary radical formation step. When a polymer sample irradiated in vacuum with ultraviolet light is treated at ?78°C for a few minutes in the presence of air, peroxy radicals form. This shows that oxygen molecules diffuse very easily into this polymer, even at this low temperature.     

Stereospecific polymerization of methacrylonitrile. V. Formation of the carbonyl in the polymer

The isotactic polymethacrylonitrile prepared by the organometallic catalysts has carbonyl groups in the polymer. Thus, the carbonyl formation during the polymerization by diethylmagnesium was carefully studied by infrared spectrometry. It was found that the imino anion formed by monomolecular termination of the propagating chain end in the cyclization reaction successively attacks the vicinal pendent nitriles in the polymer so as to form the conjugated cyclic imines, which are hydrolyzed to acid amines during the catalyst decomposition with acidic methanol.     

Separation range and separation efficiency in high-speed gel filtration on TSK-GEL SW columns

Separation ranges for gel filtration on TSK-GEL SW columns, G2000SW, G3000SW and G4000SW, were measured for globular protein, dextran and polyethylene glycol. It was possible to separate globular proteins of molecular weights from 5000 to 7,000,000, dextrans of molecular weights from 1000 to 500,000 and polyethylene glycols of molecular weights from 500 to 250,000 by using these three columns of different pore sizes. The column having the highest separation efficiency for globular proteins was also determined. The highest separation efficiency for molecular weights of less than 30,000, 30,000–500,000 and greater than 500,000 was exhibited by G2000SW, G3000SW and G4000SW, respectively.     

Preparation and properties of trimethyltris(dimethylphenylphosphine)cobalt(III)

Summary Trimethyltris(dimethylphenylphosphine)cobalt(III) has been prepared by the reaction of dimethyl(2,4-pentanedionato) bis(dimethylphenylphosphine)cobalt(III) with methyllithium in the presence of one equivalent of dimethylphenylphosphine in diethyl ether at 0°. The reaction of the trimethylcobalt(III) complex with 2,4-pentanedione in diethyl ether gave the starting dimethylcobalt complex with evolution of methane (one mol).     

Basic and clinical evaluation of a new assay procedure "SCC RIABEAD" for estimation of squamous cell carcinoma related antigen

We examined the efficacy of a new commercial assay procedure (SCC RIABEAD) for estimation of squamous cell carcinoma related antigen (SCC). Intraassay and interassay variance were 4.0-14.6% and 4.6-17.0% respectively. Recovery and dilution tests gave satisfactory results. The normal range was under the level of 1.63 ng/ml. The patients with uterine cervical cancer or squamous cell carcinoma of the lung showed high positive rates. The values of SCC measured by SCC RIABEAD were well-correlated to those by SCC RIAKIT. However, SCC RIABEAD showed lower values in low SCC level and higher values in high SCC level than SCC RIAKIT.     

Ozone Degradation by Fluoride onto Plasma-Treated Activated Carbon in CF4

The ozone degradation of fluorine was investigated using the tetrafluoromethane plasma-treated activated carbon (PT-AC). The ozone in the stratosphere has been degraded by the chloride and bromide radicals which are produced from chlorofluorocarbons and bromofluorocarbons, respectively. However, we believe that fluorine also was related to the ozone degradation. The fluoride was introduced onto the activated carbon surface by tetrafluoromethane plasma treatment. The breakthrough curve of ozone onto PT-AC was measured to elucidate the relationship between the ozone and the fluoride. The amount of ozone adsorbed/degraded onto the PT-AC was larger than the amount that was adsorbed/degraded onto the untreated activated carbon. The amount of fluoride ion eluted from the PT-AC before the adsorption/degradation of ozone was larger than that which eluted after the adsorption/degradation of ozone. These results indicated that the ozone was degraded by the fluoride on the PT-AC surface.     

Ruthenium-catalyzed oxidative cyanation of tertiary amines with molecular oxygen or hydrogen peroxide and sodium cyanide: sp3 C-H bond activation and carbon-carbon bond formation

Ruthenium-catalyzed oxidative cyanation of tertiary amines with molecular oxygen in the presence of sodium cyanide and acetic acid gives the corresponding alpha-aminonitriles, which are highly useful intermediates for organic synthesis. The reaction is the first demonstration of direct sp(3) C-H bond activation alpha to nitrogen followed by carbon-carbon bond formation under aerobic oxidation conditions. The catalytic oxidation seems to proceed by (i) alpha-C-H activation of tertiary amines by the ruthenium catalyst to give an iminium ion/ruthenium hydride intermediate, (ii) reaction with molecular oxygen to give an iminium ion/ruthenium hydroperoxide, (iii) reaction with HCN to give the alpha-aminonitrile product, H2O2, and Ru species, (iv) generation of oxoruthenium species from the reaction of Ru species with H2O2, and (v) reaction of oxoruthenium species with tertiary amines to give alpha-aminonitriles. On the basis of the last two pathways, a new type of ruthenium-catalyzed oxidative cyanation of tertiary amines with H2O2 to give alpha-aminonitriles was established. The alpha-aminonitriles thus obtained can be readily converted to alpha-amino acids, diamines, and various nitrogen-containing heterocyclic compounds.