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The composition of the catalyst layer plays an important role in the carbon dioxide reduction reaction (CO 2 RR), since it influences greatly the mass diffusion rate and the accessibility of active sites. Until now, tremendous efforts have been dedicated to the development of cathode materials with innovative characteristics, while scarce efforts have been concentrated on the study of the catalyst layer aiming at maximizing the performance of the electrodes toward the CO 2 RR. This work focuses on a full investigation of the key electrode components and their effects on the CO 2 RR performance. It is found that all key components such as Nafion binder, zinc oxide catalyst and carbon black conductor significantly affect the current density and the faradaic efficiency for carbon monoxide (CO) formation. [Display omitted] • A thorough study of the composition of a ZnO-based electrode is conducted for CO 2 RR. • All key components show significant effects on CO selectivity and production rate. • Nafion favors charge transfer while it limits electron transport and CO 2 diffusion. • Carbon black considerably increases electrical conductivity. • ZnO loading is associated with the number of active sites and their accessibility. [ABSTRACT FROM AUTHOR]

We investigate, from a topological point of view, the classes of spectral semistar operations and of eab semistar operations, following methods recently introduced in [11,13] . We show that, in both cases, the subspaces of finite type operations are spectral spaces in the sense of Hochster and, moreover, that there is a distinguished class of overrings strictly connected to each of the two types of collections of semistar operations. We also prove that the space of stable semistar operations is homeomorphic to the space of Gabriel–Popescu localizing systems, endowed with a Zariski-like topology, extending to the topological level a result established in [14] . As a side effect, we obtain that the space of localizing systems of finite type is also a spectral space. Finally, we show that the Zariski topology on the set of semistar operations is the same as the b -topology defined recently by B. Olberding [37,38] . [ABSTRACT FROM AUTHOR]

Abstract: We give a classification of e.a.b. semistar (and star) operations by defining four different (successively smaller) distinguished classes. Then, using a standard notion of equivalence of semistar (and star) operations to partition the collection of all e.a.b. semistar (or star) operations, we show that there is exactly one operation of finite type in each equivalence class and that this operation has a range of nice properties. We give examples to demonstrate that the four classes of e.a.b. semistar (or star) operations we defined can all be distinct. In particular, we solve the open problem of showing that a.b. is really a stronger condition than e.a.b. [Copyright &y& Elsevier]

Abstract: We show that in certain Prüfer domains, each nonzero ideal can be factored as , where is the divisorial closure of and is a product of maximal ideals. This is always possible when the Prüfer domain is -local, and in this case such factorizations have certain uniqueness properties. This leads to new characterizations of the -local property in Prüfer domains. We also explore consequences of these factorizations and give illustrative examples. [Copyright &y& Elsevier]

Let D be an integral domain and ★ a semistar operation on D. As a generalization of the notion of Noetherian domains to the semistar setting, we say that D is a ★-Noetherian domain if it has the ascending chain condition on the set of its quasi-★-ideals. On the other hand, as an extension the notion of Prüfer domain (and of Prüfer v-multiplication domain), we say that D is a Prüfer ★-multiplication domain (P★MD, for short) if DM is a valuation domain, for each quasi-★f-maximal ideal M of D. Finally, recalling that a Dedekind domain is a Noetherian Prüfer domain, we define a ★-Dedekind domain to be an integral domain which is ★-Noetherian and a P★MD. For the identity semistar operation d, this definition coincides with that of the usual Dedekind domains and when the semistar operation is the v-operation, this notion gives rise to Krull domains. Moreover, Mori domains not strongly Mori are ★-Dedekind for a suitable spectral semistar operation.Examples show that ★-Dedekind domains are not necessarily integrally closed nor one-dimensional, although they mimic various aspects, varying according to the choice of ★, of the “classical” Dedekind domains. In any case, a ★-Dedekind domain is an integral domain D having a Krull overring T (canonically associated to D and ★) such that the semistar operation ★ is essentially “univocally associated” to the v-operation on T.In the present paper, after a preliminary study of ★-Noetherian domains, we investigate the ★-Dedekind domains. We extend to the ★-Dedekind domains the main classical results and several characterizations proven for Dedekind domains. In particular, we obtain a characterization of a ★-Dedekind domain by a property of decomposition of any semistar ideal into a “semistar product” of prime ideals. Moreover, we show that an integral domain D is a ★-Dedekind domain if and only if the Nagata semistar domain Na(D,★) is a Dedekind domain. Several applications of the general results are given for special cases of the semistar operation ★. [Copyright &y& Elsevier]

Let R be an integral domain, I an ideal of R and ΩR(I) the Kaplansky transform of R with respect to I. A ring homomorphism α : R→A is called an I-morphism if α−1(Q)⊉I for each prime ideal Q of A. We denote by KR(I,A) the set of all the I-morphisms from R to A. It is easy to see that KR(I,−) defines a covariant functor from Ring to Set. We prove that the following statements are equivalent: (i) KR(I,−) : Ring→Set is a representable functor; (ii) the natural embedding R→ΩR(I) is an I-morphism; (iii) IΩR(I)=ΩR(I); (iv) D(I)={P∈Spec(R) | P⊉I} is an open affine subscheme of Spec(R). [Copyright &y& Elsevier]

[Display omitted] • Amino modified MWCNT sorbents are prepared with different structural properties. • Amino modified materials show CO 2 selectivity on CO 2 /N 2 adsorption-separation tests. • Higher N content and microporosity is linked with the best CO 2 up-take profiles. • The best amino-modified MWCNT material is water-resistant and multicycle reusable. Multi-walled carbon nanotubes (MWCNT) with different functionalities (standard–; OH–; and COOH– functionalized) are chemically modified with N1-(3-trimethoxysilylpropyl)diethylenetriamine (DETASi) aiming to enhance their CO 2 adsorption/separation properties. The grafting of the DETASi groups to the surface of the MWCNT samples is studied by X-ray photoelectron spectroscopy (XPS), operando thermogravimetric analysis - infrared spectroscopy (TGA-IR), –196 °C N 2 -sorption isotherms, and scanning electron microscopy (SEM). A comprehensive overview of the reaction mechanism and samples structure/composition is provided. It was found that the aforementioned functionalities highly influence the physical–chemical and the textural properties of the DETASi modified-MWCNT materials, impacting in the DETASi functionalization degree and its distribution on the sample. Amount (by TGA-IR) and homogeneity (by SEM) of the organosilicon group in the functionalized samples increases with the increase of the functionalities in the parent MWCNT materials. Standard-MWCNT and OH– functionalized MWCNT showed to be unable to adsorb CO 2 , while COOH– modified MWCNT adsorbed just 0.1% at 1 bar and 30 °C. At the same adsorption conditions, DETASi modification of the MWCNT materials enhanced the CO 2 adsorption capacity, with the maximum CO 2 uptake (2.11%) for COOH-MWCNT functionalized with DETASi. The selectivity for CO 2 /N 2 separation was also improved after DETASi grafting reaction, with the highest value (1.89%) observed for the standard-MWCNT material modified with DETASi. In general, the increase of the DETASi amount and of the microporosity in the functionalized MWCNT sorbents is accompanied by an improvement of the CO 2 adsorption-separation properties. The water vapor adsorption indicated that the standard-MWCNT sample modified with DETASi is resistant to the presence of water and its presence (water vapor of ~3.2 kPa) can improve the CO 2 uptake. [ABSTRACT FROM AUTHOR]

[Display omitted] • The submitted work is of great interest for the Journal Applied Energy due to its peculiar theme, the electrochemical CO 2 reduction, and for its approach in the investigation. Indeed, a complete ab initio modelling guided the experimental synthesis and testing of a molecular electrocatalyst which shows great performances for the CO2RR. • This work elucidate the possibility to activate the CO 2 through organic molecules and, moreover, shows the feasibility of this approach to be completely integrated inside a TRL 3–4 electrolysis cell. The electrochemical reduction of CO 2 to value-added products is hindered by its thermodynamic stability and by the large energy required to chemically activate the molecule. With this respect, forcing CO 2 in a non-linear geometry would induce an internal electron charge rearrangement which would facilitate further electrochemical transformations. In this work, we achieved this goal through the design of a dual function electro-organocatalyst, which exploits the ability of the imidazolate (Im-) lone pair to bind CO 2 via nucleophilic attack and then electrochemically reduce it. To give structural stability to the Im- based catalyst, the imidazoles species are incorporated into a solid structure, namely ZIF-8. Once activated by the organic Im- ligand, CO 2 is electrochemically reduced to CO when a bias is applied to ZIF-8. The catalyst proposed in our study was first devised by computer aided design based on Density functional Theory simulations and then realized in laboratory. Our results demonstrate that ZIF-8 supported on conductive CNTs presents surface Im- active sites which convert CO 2 into CO with a high faradaic efficiency (70.4 %) at −1.2 V vs reversible hydrogen electrode, by combining chemical activation with electrochemical catalysis. [ABSTRACT FROM AUTHOR]

Catalysts play a vital role in electrochemical reduction of CO 2 to valuable products. Only based on effective catalysts, CO 2 electrolysis process can be advanced toward industrial application. In this work, we present a Sb-Cu 2 O material synthesized via one-pot microwave-assisted solvothermal route. The Sb-Cu 2 O derived bimetallic catalyst achieves a highest CO selectivity of 96% and good CO partial current densities of 37.3 and 74.0 mA cm−2 at − 0.8 and − 1.2 V vs. reversible hydrogen electrode (RHE), respectively. The Sb-Cu catalyst also displays good stability at current densities ranging from 5.6 to 100 mA cm−2. Additionally, for the first time, a complete theoretical study reveals the critical roles of Sb in selective CO 2 conversion to CO on this bimetallic material, including stabilizing stepped Cu surfaces selective for the reaction, lowering energy barriers for the formation of key intermediate and favouring CO desorption. [Display omitted] • Sb-Cu 2 O material is synthesized via a one-pot microwave-assisted route. • Sb is uniformly distributed and promotes the formation of nanocrystalline Cu 2 O. • The derived Sb-Cu shows outstanding performance for the CO 2 RR to CO. • Enhancing local CO 2 concentration is demonstrated to boost CO formation rate. • Theoretical study reveals the critical roles of Sb in CO formation on Sb-Cu. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reverse micelle synthesis fosters Fe doping of nanocrystalline CeO 2. • 2.5 mol % iron-doped ceria leads to high charge delocalization. • Efficient visible-light photodegradation of ibuprofen with 2.5 mol % Fe-CeO 2. • Substitutional Fe favours the oxygen vacancies formation and ibuprofen adsorption. • The by-product of the ibuprofen degradation is 1-ethenyl-4-(2-methylpropyl)benzene. Reverse micelle nanoreactors were successfully designed to synthesize small-sized ceria nanocrystals (3.5–4.2 nm) with a sizeable amount of substitutional iron. Undoped and doped CeO 2 catalysts with an iron content (0.50–10 mol %) compliant with the nominal value were prepared and tested for the first time for the removal of ibuprofen both in the dark and under UV or visible light irradiation. The effective inclusion and distribution of iron in the ceria lattice were ascertained through in-depth physicochemical characterization. In particular, X-ray diffraction suggested the formation of an F-type crystal structure, ruling out the formation of separate iron-containing crystalline phases. On the other hand, substitutional doping of CeO 2 with Fe atoms favoured the formation of Ce3+ defects and vacancy sites (VOs) with a maximum for the sample with 2.5 mol % iron (Fe2.5), as evidenced by X-ray photoelectron spectroscopy (XPS) measurements and Raman spectroscopy. UV–Vis spectroscopy showed that the optical properties were successfully modified by the presence of iron, which causes a gradual decrease in band gap as iron content increases. The experimental evidence was further verified and supported by density functional theory calculations. DFT calculations also revealed that the surface iron and oxygen vacancies are the preferential sites for ibuprofen adsorption. Nevertheless, it was found under dark conditions that adsorption capacity does not monotonically increase with iron content, revealing contrasting roles of surface characteristics. Indeed, catalytic experiments have identified a trade-off between adsorption and photodegradation, identifying Fe2.5 as the best-performing catalyst for ibuprofen removal under visible light irradiation. These results were discussed by considering the key properties of the catalysts as well as their different surface charge determined by ζ potential measurements. The best catalyst was tested through reuse experiments that proved its stability over 4 cycles. Finally, an attempt was made to identify the photodegradation by-products, allowing the detection of 1-ethenyl-4-(2-methylpropyl)benzene as the main by-product. [ABSTRACT FROM AUTHOR]

Abstract: Let be a ring homomorphism and let be an ideal of . In this paper, we study the amalgamation of with along with respect to (denoted by ), a construction that provides a general frame for studying the amalgamated duplication of a ring along an ideal, introduced and studied by D’Anna and Fontana in 2007, and other classical constructions (such as the , the and the constructions). In particular, we completely describe the prime spectrum of the amalgamated duplication and we give bounds for its Krull dimension. [Copyright &y& Elsevier]

Highly efficient, separable, and stable magnetic iron-based-photocatalysts produced from ultra-stable Y (USY) zeolite were applied, for the first time, to the photo-Fenton removal of phenol under solar light. USY Zeolite with a Si/Al molar ratio of 385 was impregnated under vacuum with an aqueous solution of Fe2+ ions and thermally treated (500–750 °C) in a reducing atmosphere. Three catalysts, Fe-USY500°C-2h, Fe-USY600°C-2h and Fe-USY750°C-2h, containing different amounts of reduced iron species entrapped in the zeolitic matrix, were obtained. The catalysts were thoroughly characterized by absorption spectrometry, X-ray powder diffraction with synchrotron source, followed by Rietveld analysis, X-ray photoelectron spectroscopy, N 2 adsorption/desorption at −196 °C, high-resolution transmission electron microscopy and magnetic measurements at room temperature. The catalytic activity was evaluated in a recirculating batch photoreactor irradiated by solar light with online analysis of evolved CO 2. Photo-Fenton results showed that the catalyst obtained by thermal treatment at 500 °C for 2 h under a reducing atmosphere (FeUSY-500°C-2h) was able to completely mineralize phenol in 120 min of irradiation time at pH = 4 owing to the presence of a higher content of entrapped nano-sized magnetite particles. The latter promotes the generation of hydroxyl radicals in a more efficient way than the Fe-USY catalysts prepared at 600 and 750 °C because of the higher Fe 3 O 4 content in ultra-stable Y zeolite treated at 500 °C. The FeUSY-500°C-2h catalyst was recovered from the treated water through magnetic separation and reused five times without any significant worsening of phenol mineralization performances. The characterization of the FeUSY-500°C-2h after the photo-Fenton process demonstrated that it was perfectly stable during the reaction. The optimized catalyst was also effective in the mineralization of phenol in tap water. Finally, a possible photo-Fenton mechanism for phenol mineralization was assessed based on experimental tests carried out in the presence of scavenger molecules, demonstrating that hydroxyl radicals play a major role. [Display omitted] • Stable catalysts were prepared by entrapping Fe species in ultra-stable Y zeolite. • The catalyst's magnetic properties allow easy separation and reuse. • Complete phenol removal is achieved by solar light-driven photo-Fenton reaction. • Phenol mineralization increases with Fe 3 O 4 content in ultra-stable Y zeolite. • Hydroxyl radicals play the main role in the removal of phenol under solar light. [ABSTRACT FROM AUTHOR]

• CO oxidation was studied by in situ Raman spectroscopy on nanostructured ceria-based materials. • In situ Raman analyses during CO oxidation allowed to monitor defect sites in operando conditions. • Cycles of reduction (CO in N 2) and oxidation (pure O 2) at 400 °C allow to study the stability of defects. • Oxygen vacancies evolved from clusters to isolated ones according to the atmosphere and temperature. • The involvement of the defect sites in structural rearrangement is fostered by easily reducible dopants. Among the factors affecting ceria activity, the defectiveness plays a key role in the case of CO oxidation. In this study, its connection with the catalytic performance was investigated via in-situ Raman spectroscopy on nanostructured pure and Cu/Mn-doped ceria, monitoring the defect sites and surface species evolution during the reaction. The accumulation of polyene-like chains, formed through CO dissociative adsorption at the catalyst surface, was observed and their disappearance was related to the catalyst light-off temperature. Moreover, the doped samples exhibited a rise of the Raman bands associated to defects after the tests, consequence of the structural rearrangements occurring during CO oxidation. Indeed, in-situ Raman measurements during reduction (CO/N 2) and oxidation cycles at 400 °C evidenced the formation of oxygen vacancy clusters in reducing atmosphere, which could reorganize not only in O 2 but also upon a temperature decrease, forming isolated vacancies and then evolving in Frenkel and extrinsic oxidized dopant-containing sites when exposed to oxygen. [ABSTRACT FROM AUTHOR]

Endocrine disruptors (EDCs) are emerging contaminants that are harmful to health. Human exposure occurs mainly through ingestion or dermal contact, but inhalation could be an additional exposure route; therefore, this study was conducted to evaluate the oestrogenic activity of airborne particulate matter (PM). Outdoor PM was collected for a year in five Italian sites and extracted with organic solvents (four seasonal extracts/site). The oestrogenic activity was assessed using a gene reporter assay (MELN), and the risk to human health through inhalation was quantified using the results. Moreover, extracts were analysed to assess cytotoxicity (WST-1 and LDH assays) on human bronchial cells (BEAS-2B). The extracts induced a significant cytotoxicity and oestrogenic activity. Oestrogenic activity showed a seasonal trend and was correlated with concentrations of benzo(a)pyrene and toxic equivalency factor. Although a low inhalation cancer risk was found, this study confirmed that oestrogenic activity in air could contribute to overall health risks due to EDC exposure. [Display omitted] • Oestrogenic activity of particulate matter (PM) extracts by a gene reporter assay. • Assessment of the inhalation cancer risk due to oestrogenic pollutants on PM. • Significant oestrogenic activity of airborne PM extracts with a seasonal trend. • PM oestrogenic activity correlated with benzo(a)pyrene and toxicity of PAHs. • Airborne PM may contribute to EDC body burden, but oestrogenic cancer risk is low. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe and/or Cr doped TiO 2 photocatalysts were successfully prepared by sol–gel method. • The photocatalytic process made the effluent suitable for MBBR treatment. • Fe-doped TiO 2 showed the highest TPHs removal efficiency. • H 2 O 2 addition drastically improved TPHs removal (97%) from OMW. • Post-treatment is the best option for application of photocatalysis to OMW. TiO 2 based-photocatalysts doped with Fe and/or Cr was evaluated as pre- and post-treatment method of a moving bed biofilm reactor (MBBR) as possible solution for the treatment of real olive oil mill wastewater (OMW). Photocatalysts were synthesized by wet chemical method and their chemical-physical properties were accurately investigated through X-ray diffraction (XRD), Raman spectroscopy, UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS) and specific surface area measurements. UV–Vis DRS measurements evidenced that the simultaneous doping of TiO 2 lattice with Fe and Cr improves the optical absorption into the visible region leading to a narrow band gap (2.1 eV) with respect to undoped TiO 2 (3.2 eV) and Fe-doped TiO 2 (2.8 eV) while, Cr-doped TiO 2 showed the lowest bandgap value (1.9 eV). XRD patterns and Raman spectra showed that anatase is the predominant crystalline phase for all the prepared photocatalysts and Fe and Cr ions were effectively inserted into the TiO 2 lattice. The TiO 2 doping with Cr did not change the average crystallites size that was equivalent to that of TiO 2 (8 nm), whereas, for Fe- doped TiO 2 , it was lower than the others and equal to 6 nm. The specific surface area values of doped catalysts were higher than TiO 2 and the value for Fe-Cr-codoped TiO 2 resulted to be 97 m2 g−1. Photocatalytic treatment of OMW was evaluated in terms of total polyphenols (TPHs), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD 5) and biodegradability (as BOD 5 /COD ratio) in 3 h of treatment under simulated solar light irradiation. Fe-doped TiO 2 showed the highest TPHs removal for both un-treated and biologically treated OMW. When H 2 O 2 was added (optimum dosage 0.5 g L-1), Fe-Cr-TiO 2 resulted in the best photocatalytic performance with TPHs removal as high as 97% and increased biodegradability (0.22 to 0.33), making the effluent suitable for the subsequent biological process. When photocatalytic process was investigated as post-treatment of OMW, Fe-TiO 2 showed the best activity and the addition of 0.5 g L-1 of H 2 O 2 was sufficient to make the effluent in compliance with Italian regulation for effluent disposal into surface water. [ABSTRACT FROM AUTHOR]

Commercial Mn 2 O 3 , Mn 3 O 4 and MnO 2 and the same after thermal or ball-milling treatments have been examined as catalysts for the photocatalytic water oxidation reaction, using [Ru(bpy) 3 ] 2+ as photosensitizer and S 2 O 8 2− as sacrificial electron acceptor. Tests were performed in a bubbling reactor, allowing the calculation of the actual rate of O 2 evolution as a function of time from raw data (oxygen flow, concentration of dissolved oxygen, DO) through a model able to take into account mass transfer phenomena Hernández et al. [19]. A few parameters are proposed for measuring activity, and comparison among them is made. The activity per unit mass of commercial samples is Mn 2 O 3 > MnO 2 > Mn 3 O 4 , in agreement with the literature. Increase in the surface area brought about by milling correspond, as expected, to a steady increase in activity in the case of Mn 3 O 4 , whereas had no effect with Mn 2 O 3 . The markedly higher specific surface of Mn 2 O 3 and Mn 3 O 4 samples obtained by thermal treatment of MnO 2 and a home-made sample, respectively, correspond surprisingly to activities lower than low surface area ball milled samples. Reasons for this are proposed to be a different nature of the surfaces arrived at, because of the different preparation route. A similar study of the effect of surface area for MnO 2 specimens is prevented by their largely amorphous nature. Comparison of present data with those already reported gives further support to the bounty of the model taking into account mass transfer. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of a series of azobenzene containing liquid crystalline methacrylic homopolymers, poly(4-ω-methacryloyloxy-hexyloxy-4′-ethoxyazobenzene) [Poly(M6A)], with distinct average chain lengths and low polydispersity has been achieved by Atom Transfer Radical Polymerization (ATRP) in THF solution using allyl 2-bromoisobutyrate as initiator and Cu(I)Br as catalyst. Under the adopted conditions the living centers concentration is found to be constant throughout the polymerization process and well defined chain end-groups are obtained. All the obtained polymeric samples, having average molecular mass ranging from 3300 to 14000g/mol, exhibit smectic and nematic liquid-crystalline phases on heating, with transition temperatures strongly dependent on polymerization degree, as characterized by differential scanning calorimetry and polarized optical microscopy. The photomechanical effects (i.e. the dependence of volume and density) exhibited upon trans-to-cis and cis-to-trans photoisomerization of the azobenzene mesogenic groups have been investigated by ellipsometry and related to molecular weight, with particular attention to important parameters for potential applications such as the relative variation of total volume, response time, stability and reproducibility. [Copyright &y& Elsevier]

Abstract: A polyaniline–polyethylene oxide hybrid electrochemical device was fabricated and its stability was studied analyzing cyclically acquired voltage–current characteristics. The results show reproducibility of data during a rather long working period (at least 4000min). Such stability is adequate for the use of the polymeric electrochemical heterojunctions as key nodes of adaptive networks capable of “intelligent response” to training procedures. [Copyright &y& Elsevier]

Abstract: We report here on our recent structural and spectroscopic studies of the complexes formed when DNA is attached to Langmuir layers, in particular to octadecylamine layer. Synchrotron radiation reflectivity points out that in the case of amino–DNA complex, even if the subphase contains DNA in its native double stranded form, the formed complex consists of denaturated, single stranded DNA, opposite to the more common case in which a complex is formed with DNA in its native, double stranded form. This result is also supported by spectroscopic FT-IR and ellipsometric studies, and is shown to occur only in the presence of the amino group. Basing on this, we suggest here that an adaptive sensing element for a new DNA sensor for the crude recognition of DNA could be build exploiting the capability of the amino group to induce DNA splitting into the single stranded form. Such sensor will be “taught” by exposure to the DNA that is to be detected, which will attach in the denaturated form. The sensor will then be capable of recognizing by hybridization to the complementary part of the particular DNA sequence for which it was prepared. After usage, the sensing element could then be “erased” by exposure to high temperature or to strong basic conditions, to remove the DNA single strand attached to the amino groups, and then it would be usable again for the detection of any other particular DNA sequence of interest. [Copyright &y& Elsevier]