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Chlorofluorocarbon (CFC‐113), CHCl3 and CCl4 have been photolysed in the presence of H2O, and the decomposed species scavenged by the reaction with a metal powder. The decomposition of these hazardous compounds was almost 100%. All chlorine atoms were fixed in the form of metal chlorides, and no gaseous product existed except CO2. The scavenging reaction of generated reactive species was brought about by the oxidation of the metal, and hence divalent and trivalent metal compounds showed only insignificant scavenging efficiency.

A new exclusion process for CO and CO2 from ammonia synthesis gas has been proposed: this takes place at room temperature and atmospheric pressure. The process is based on the electrochemical reduction of CO and CO2 to methanol proceeding at a mediated electrode via homogeneous catalysis. The maximum percentages of CO and CO2 excluded from the initial gas were about 1.5 and 4.1%, respectively, with a mediated electrode of 82.8 cm2 area in a reaction time of 5 h. The amount of excluded CO and CO2 was equivalent to the sum of moles of methanol formed and gases dissolved into the solution alone. The electroreduction of CO and CO2 was more efficient at three-phase (electrode/solution/gas) and at two-phase (electrode/solution) interfaces, respectively.

Combined photochemical and electrochemical oxidation of methane has led to the formation of methyl chloride and methanol at room temperature. This process consists of the electro‐oxidation of the chloride ion, generation of chlorine radical under the illumination of light, hydrogen‐abstraction from methane by Cl, formation of methyl chloride, and hydrolysis of to methanol. The hydrolysis reaction takes place with the activation energy of 24.3 kcal mol−1. The suppression of higher substitution products was more effective in rectangular‐wave than regular potentiostatic electrolysis, which results from the termination of the chain reactions owing to the periodic exhaustion of chlorine radicals.

This paper reports the catalytic reduction of carbon dioxide to methanol achieved with a hydrogen fuel cell. This process involves a homogeneous and a heterogeneous catalysis. In the former, the catalyst consisting of a metal complex and methanol were applied, and in the latter Everitt's salt (K{sub 2}Fe{sup II}(Fe{sup II}(CN{sub 6}))) which functions as an electron relay was used. The initial {ital p}H of the catholyte was fixed at 2, and the {ital p}H of the anolyte was required to be higher than 1.75 for the hydrogen fuel cell with CO{sub 2} as oxidant to be feasible thermodynamically.

A versatile diatomic physiological messenger, nitric oxide (NO), is biosynthesized by a group of flavo-heme enzymes, the nitric oxide synthases. We have examined the active site of the neuronal isoform by EPR spectroscopy of the ferrous nitric oxide complex. The nitric oxide complex of the substrate-free enzyme exhibits a cytochrome P450-type EPR spectrum typical of a hexacoordinate NO-heme complex with a non-nitrogenous proximal axial heme ligand. The NO complex of the substrate-free enzyme is rather unstable and spontaneously converts to a cytochrome P420 type pentacoordinate denatured form. Binding of L-arginine (l-Arg) enhances the stability of the hexacoordinate NO form. The EPR spectrum of the NO adduct of the enzyme-substrate complex has an increased g-anisotropy and well-resolved hyperfine couplings due to the 14N of nitric oxide. Significant perturbations in the NO EPR spectrum were observed upon Nomega-monomethyl-L-Arg and Nomega-hydroxy-L-Arg binding. The perturbations in the EPR spectrum indicate that L-Arg and its derivatives bind on the distal site of the heme in very close proximity to the bound NO to cause alterations in the heme-NO coordination structure. Interactions between the bound NO and the substrate or its analogues appear to affect the Fe-NO geometry, resulting in the observed spectral changes. We infer that analogous interactions with oxygen might be involved in the hydroxylation events during enzyme catalysis of nitric oxide synthase.