The reaction between methane and oxygen over platinum and rhodium surfaces in metalcoated ceramic monoliths can be made to produce mostly hydrogen and carbon monoxide (greater than 90% selectivity for both) with almost complete conversion of methane and oxygen at reaction times as short as 10(-3) seconds. This process has great promise for conversion of abundant natural gas into liquid products such as methanol and hydrocarbons, which can be easily transported from remote locations. Rhodium was considerably superior to platinum in producing more H(2) and less H(2)O, which can be explained by the known chemistry and kinetics of reactants, intermediates, and products on these surfaces.

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Electron energy loss spectroscopy (EELS) has been used to study the adsorption of nitric oxide on Rh(111). NO adsorbs in twofold bridge sites at all coverages. The dissociation rate of NO on this surface at low coverage has been measured directly using EELS. The first order dissociation rate parameters are Ea =19.2±0.3 kcal/mol and ν(1)0 =1×1014±0.3 s−1 at θNO ≊0.2. Ordered low energy electron diffraction (LEED) patterns are observed only for partially dissociated NO adlayers and not for NO adsorbed molecularly at 95 K. Because NO adsorbs in twofold bridge sites at all coverages, the N–O stretching frequency exhibits a 150 cm−1 shift from zero to saturation coverage.

This study was designed to evaluate the effects of a self-management training (SMT) program on metabolic control of children with insulin-dependent diabetes mellitus (IDDM) in the first 2 yr after diagnosis. After standard in-hospital diabetes education, 36 children (mean age 9.3 yr, range 3-16 yr) were randomized to conventional follow-up, conventional and supportive counseling (SC), or conventional and SMT, which emphasized use of data obtained from self-monitoring of blood glucose. SC and SMT interventions consisted of seven outpatient sessions with a medical social worker during the first 4 mo after diagnosis and booster sessions at 6 and 12 mo postdiagnosis. Groups were similar with respect to age, sex, body mass index, socioeconomic status, C-peptide, and severity of illness at diagnosis. Metabolic control, measured quarterly by glycosylated hemoglobin (HbA1), improved substantially in all three treatment groups during the first 6 mo. SMT patients had significantly lower HbA1 levels than conventional patients at 1 yr (P less than 0.01) and 2 yr (P less than 0.05) postdiagnosis. SMT patients also had lower HbA1 levels than SC patients, but this did not reach statistical significance. The lower HbA1 levels of SMT patients were not explained by severity of illness at diagnosis, or insulin dose, body mass index, and C-peptide levels at 2 yr. These results suggest that an SMT program during the first few months after diagnosis helps avoid the deterioration in metabolic control often seen in children with IDDM between 6 and 24 mo after diagnosis.