We develop an experimental protocol to quantify the speciation of Cu ions (ZCu II OH and Z 2 Cu II ) in Cu-CHA catalysts for the NH 3 Selective Catalytic Reduction of NOx (NH 3 -SCR). Toward this end, we performed four transient tests, namely H 2 -TPR, NO + NH 3 TPR, NO 2 adsorption + TPD, and NH 3 adsorption + TPD, over two sets of Cu-CHA research catalysts characterized by different Cu contents (0−2.1% w/w) and SiO 2 /Al 2 O 3 (SAR) ratios (10−25). Preliminary H 2 -TPR tests on the samples with the extreme SAR and Cu loading values were used to identify the variability range of the fractions of ZCu II OH and Z 2 Cu II species in these catalysts. The ZCu II OH fraction was found to vary between 0.55 (at Cu/Al = 0.11) and 0.79 (at Cu/Al = 0.29). NO+NH 3 TPR runs demonstrated that the NO + NH 3 mixture is a much stronger reducing agent than H 2 : full reduction of all the Cu was obtained already at lower temperature, and differences in the reducibility of ZCu II OH and Z 2 Cu II were strongly attenuated. Both the integral NO consumption and the integral N 2 release were found to be effective estimators of the reducible Cu in Cu-CHA, matching the total Cu from ICP measurements. NO 2 adsorption + TPD tests pointed out that NO 2 is adsorbed in the form of nitrates on ZCu II OH ions only, the nitrates storage capacity being therefore dependent on SAR and Cu loading: on increasing both parameters, the amount of stored NO x increased, as well as their stability. Both the NO released during isothermal NO 2 adsorption and the NO 2 released during the following TPD can be used to directly estimate the number of ZCu II OH ions in Cu-CHA. Finally, NH 3 -TPD provided information on the acid sites in the Cu-CHA samples. From the NH 3 stored on Lewis sites, it was possible to evaluate the number of NH 3 molecules coordinated to each Cu atom: a decrease of the NH 3 /Cu ratio on increasing both SAR and Cu content was observed. This behavior is explained by the changes in the distribution of ZCu II OH and Z 2 Cu II sites in Cu-CHA, as a result of varying the Cu/Al ratio. In accordance with literature results, we found that Cu ions are able to ligate either 3 (ZCu II OH) or 4 (Z 2 Cu II ) NH 3 molecules, when gaseous NH 3 is present, the NH 3 /Cu ratios estimated from our experiments falling close to this range. When only preadsorbed NH 3 was present, however, (no gaseous ammonia), the NH 3 /Cu ratio dropped to either 1 (ZCu II OH) or 2 (Z 2 Cu II ). On the basis of these elements, NH 3 TPD can also be used to quantify the two Cu species in Cu-CHA. We recommend however the more straightforward approach based on (i) NO + NH 3 TPR (for direct quantification of the overall reducible Cu) and (ii) NO 2 TPD (for direct quantification of the ZCu II OH species).

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3We report a mechanistic DRIFTS in-situ study of NO 2 , NO + O 2 and NO adsorption on a 4 commercial Cu-CHA catalyst for NH 3 -SCR of NOx. Both pre-reduced and pre-oxidized catalyst 5 samples were investigated with the aim to clarify mechanistic aspects of the NO oxidation to NO 2 6 as a preliminary step towards the study of the Standard SCR reaction mechanism at low 7 temperatures. Nitrosonium cations (NO + , N oxidation state = +3) were identified as key surface 8 intermediates in the process of NO (+2) oxidation to NO 2 (+4) and nitrates (+5). While NO + and 9 nitrates were formed simultaneously upon catalyst exposure to NO 2 , nitrates evolved consecutively 10 to NO + when the catalyst was exposed to NO + O 2 , suggesting that nitrite-like species, and not NO 2 , 11 are formed as the primary products of the NO oxidative activation over Cu-CHA. Upon catalyst 12 exposure to NO only, i.e. in the absence of gaseous O 2 , NO + and then nitrates were formed on a 13 preoxidized sample but not on a prereduced one, which demonstrates the red-ox nature of the NO 14 oxidation mechanism. The negative effect of H 2 O on NO + and nitrates formation was also clearly 15 established. Assuming small Cu clusters, in the form of Cu dimers, as the active sites for NO 16 oxidation to NO 2 , we propose a mechanism which reconciles all the experimental observations. In 17 particular, we show that such a mechanism also explains the observed kinetic effects of H 2 O, O 2 18 and NO 2 on the NO oxidation activity of the investigated Cu zeolite catalyst. 19 20 21

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Background: Many studies have shown that estrogen replacement therapy may improve cognitive function in women and reduce the risk of Alzheimer’s disease (AD). Because most of the estrogen neuroprotective effect is mediated by receptors, we studied the associations between estrogen receptor α (ESR1) polymorphisms (PvuII and XbaI) and AD, and their interactions with apolipoprotein E (APOE) polymorphism and plasma levels. Methods: ESR1 genotypes and APOE plasma concentrations were determined in a sample of AD patients and controls. Results: ESR1 PP and XX genotypes were associated with an increased risk for AD only in males (OR = 3.6, 95% CI = 1.2–10.9) and conferred a relevant additional risk of AD to subjects also carrying APOE e*4 allele (OR = 13.3, 95% CI = 1.7–103.6). Mean APOE concentrations were lower in AD patients; the lowest levels were observed in male patients carrying PP and/or XX genotypes (p = 0.006) and in patients carrying PP and/or XX genotypes together with the e*4 allele (p = 0.003). In AD women, ESR1 PP and XX genotypes were also associated with lower MMSE values (p = 0.0007). Conclusion: The present data suggest that the involvement of ESR1 polymorphisms in AD onset is mediated by the regulation of apoE expression. ESR1 polymorphisms are also associated with a faster cognitive decline in the women AD patients.

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