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Methanol synthesis by CO2 hydrogenation is attractive in view of avoiding the environmental implications associated with the production of the traditional syngas feedstock and mitigating global warming. However, there still is a lack of efficient catalysts for such alternative processes. Herein, we unveil the high activity, 100 % selectivity, and remarkable stability for 1000 h on stream of In2 O3 supported on ZrO2 under industrially relevant conditions. This strongly contrasts to the benchmark Cu-ZnO-Al2 O3 catalyst, which is unselective and experiences rapid deactivation. In-depth characterization of the In2 O3 -based materials points towards a mechanism rooted in the creation and annihilation of oxygen vacancies as active sites, whose amount can be modulated in situ by co-feeding CO and boosted through electronic interactions with the zirconia carrier. These results constitute a promising basis for the design of a prospective technology for sustainable methanol production.

We review synthetic, mechanistic and process aspects of the direct syngas conversion into higher alcohols to foster the identification of industrially-viable catalysts.

In the recent years, significant progress has been made toward designing active and selective catalysts for electrochemical CO2 reduction, with particular interest focused on the two major C2 products—ethylene and ethanol. Numerous efforts have been made to enhance the understanding of the heterogeneous copper-based CO2 reduction mechanisms by computational studies. Here we provide a critical assessment of various proposed scenarios of the initial and post C–C coupling steps that result in either ethylene or ethanol. In silico rationalization of the parameters controlling the product selectivity, such as the catalyst structure and composition (Cu facets, the presence of defective sites and/or subsurface oxygen atoms, or the interplay with a second metal) and the reaction conditions (pH, applied potential, and electrolyte), is provided. A comprehensive scheme combining the proposed pathways is derived, and the issues that are still under debate and require further investigations are highlighted.

Abstract With the necessity for the refining industry to treat heavier feedstocks, there is a clear demand for improved zeolite materials displaying better accessible surface areas and higher pore volumes in order to capitalize on their effectiveness. To this end, over the last decade, there has been an intensification of research on the exploration of new routes to synthesize zeolite materials combining micropores with mesopores. Different synthesis strategies are used for their preparation (i.e., by structure breaking or so‐called ‘destructive’ pathways, or structure building or so‐called ‘constructive’ synthesis pathways). This Review discusses the variety of current synthesis strategies, while emphasizing the strengths and weaknesses of the different routes regarding material characteristics; health, safety, and environment aspects; and synthesis costs.

The disposition of the intravenous anesthetic propofol was studied when administered as a constant rate infusion at 3, 6, and 9 mg.kg-1.hr-1 for at least 2 hr to three groups of six patients each undergoing surgery under regional anesthesia. Arterial blood samples were collected at selected times during and up to 8 hr after infusion. Whole blood propofol concentrations were determined by high-performance liquid chromatography with fluorescence detection. Using a non-linear least-squares regression analysis, the individual data sets were best fitted by a three-compartment open mamillary model with central elimination in 17 patients. In one patient a biexponential equation was more appropriate. Derived pharmacokinetic parameters expressed as mean values +/- SD indicated an initial fast distribution (t1/2 pi; 2.8 +/- 1.2 min), with an intermediate phase (t1/2 alpha; 31.4 +/- 14.7 min), and a long terminal phase (t1/2 beta; 355 +/- 227 min), a large volume of distribution at steady state (Vss, 287 +/- 213 L), and a high blood clearance (Clb, 1.7 +/- 0.3 L/min). The function of drug in the central compartment in the terminal phase was low (Fc, 0.02). The elimination rate constant (K10, 0.1190 +/- 0.0351 min-1) was large compared with the other transfer rate constants and was responsible for the large amount of drug eliminated during distribution. The fraction of drug eliminated during the terminal phase amounted to 0.28. The slow return of drug from remote tissues (K31, 0.0033 +/- 0.0013 min-1) was rate limiting in the ultimate elimination.(ABSTRACT TRUNCATED AT 250 WORDS)

Abstract Metal promotion is broadly applied to enhance the performance of heterogeneous catalysts to fulfill industrial requirements. Still, generating and quantifying the effect of the promoter speciation that exclusively introduces desired properties and ensures proximity to or accommodation within the active site and durability upon reaction is very challenging. Recently, In 2 O 3 was discovered as a highly selective and stable catalyst for green methanol production from CO 2 . Activity boosting by promotion with palladium, an efficient H 2 -splitter, was partially successful since palladium nanoparticles mediate the parasitic reverse water–gas shift reaction, reducing selectivity, and sinter or alloy with indium, limiting metal utilization and robustness. Here, we show that the precise palladium atoms architecture reached by controlled co-precipitation eliminates these limitations. Palladium atoms replacing indium atoms in the active In 3 O 5 ensemble attract additional palladium atoms deposited onto the surface forming low-nuclearity clusters, which foster H 2 activation and remain unaltered, enabling record productivities for 500 h.

Working at the Y: Zeolite Y crystals with micropores (ca. 1 nm), small mesopores (ca. 3 nm), and large mesopores (ca. 30 nm) were obtained by base leaching of previously steamed and acid-leached material. The zeolite Y crystals with trimodal porosity (see electron-tomographic picture) displayed close to ideal hydrocracking selectivity and enhanced yields of kerosene and diesel. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Monoclinic zirconia has been uncovered as a carrier able to substantially boost the activity of indium oxide for CO2 hydrogenation to methanol. Here, electronic, geometric, and interfacial phenomena associated with this peculiar effect are investigated. Generating mixed In–Zr oxides by coprecipitation does not improve performance, excluding a primary role of electronic parameters. Because even only 1 mol % of indium stabilizes the metastable tetragonal phase of zirconia, the relevance of its crystalline structure is explored in impregnated solids. Both tetragonal and monoclinic ZrO2 permit epitaxial growth of In2O3, but a more pronounced lattice mismatching leads to a lower dispersion of the oxide on the second, which is observed in the form of subnanometric islands on the carrier, and to more pronounced tensile forces. The latter triggers the formation of a surplus of oxygen vacancies only in this system, which is in line with its greatly enhanced indium-specific activity. Hence, a deposition synthesis method is essential to unlock the role of monoclinic zirconia. According to kinetic analyses, the monoclinic ZrO2-based catalyst can also better activate both reactants, likely because of a superior character of oxygen vacancies on supported In2O3 and a direct contribution of zirconia to CO2 activation on its own oxygen vacancies, which was investigated in comparison with In2O3 supported on alumina and ceria. Elucidating the nature of the active sites at the phase boundary and the impact of the defect chemistry of zirconia are identified as aspects to be prioritized in upcoming studies to shed further light on interfacial effects in this relevant catalytic system.

Department of Pathology, Academic Hospital Jette, Free University of Brussels, Belgium Address correspondence and reprint requests to Dr. Günter Kloppel, Professor and Chairman, Department of Pathology, Academic Hospital Jette, Free University of Brussels, Laarbeeklaan, 101, B-1090, Brussels, Belgium. Manuscript received December 1, 1992; revised manuscript accepted February 9, 1993.

Zeolites have been game-changing materials in oil refining and petrochemistry over the last 60 years and have the potential to play the same role in the emerging processes of the energy and environmental transition. Although zeolites are crystalline inorganic solids, their structures are not perfect and the presence of defect sites - mainly Brønsted acid sites and silanols - influences their thermal and chemical resistance as well as their performances in key areas such as catalysis, gas and liquid separations and ion-exchange. In this paper, we review the type of defects in zeolites and the characterization techniques used for their identification and quantification with the focus on diffraction, spectroscopic and modeling approaches. More specifically, throughout the review, we will focus on silanol (Si-OH) defects located within the micropore structure and/or on the external surface of zeolites. The main approaches applied to engineer and heal defects and their consequences on the properties and applications of zeolites in catalysis and separation processes are highlighted. Finally, the challenges and opportunities of silanol defect engineering in tuning the properties of zeolites to meet the requirements for specific applications are presented.

ADVERTISEMENT RETURN TO ISSUEPREVViewpointNEXTEthylene Electrosynthesis: A Comparative Techno-economic Analysis of Alkaline vs Membrane Electrode Assembly vs CO2–CO–C2H4 TandemsJared SislerJared SislerDepartment of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, CanadaMore by Jared Sislerhttp://orcid.org/0000-0002-0660-7909, Shaihroz KhanShaihroz KhanDepartment of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, CanadaDepartment of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, CanadaMore by Shaihroz Khan, Alexander H. IpAlexander H. IpDepartment of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, CanadaMore by Alexander H. Ip, Moritz W. SchreiberMoritz W. SchreiberRefining and Chemicals, TOTAL Research and Technology, Feluy, 7181 Seneffe, BelgiumMore by Moritz W. Schreiber, Shaffiq A. JafferShaffiq A. JafferTOTAL American Services Inc., Hopkinton, Massachusetts 01748, United StatesMore by Shaffiq A. Jafferhttp://orcid.org/0000-0001-9311-4469, Erin R. BobickiErin R. BobickiDepartment of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario M5S 3E5, CanadaMore by Erin R. Bobicki, Cao-Thang Dinh*Cao-Thang DinhDepartment of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, CanadaDepartment of Chemical Engineering, Queen's University, 19 Division Street, Kingston, Ontario K7L 3N6, Canada*Email: [email protected]More by Cao-Thang Dinhhttp://orcid.org/0000-0001-9641-9815, and Edward H. Sargent*Edward H. SargentDepartment of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada*Email: [email protected]More by Edward H. Sargenthttp://orcid.org/0000-0003-0396-6495Cite this: ACS Energy Lett. 2021, 6, 3, 997–1002Publication Date (Web):February 16, 2021Publication History Received19 December 2020Accepted4 February 2021Published online16 February 2021Published inissue 12 March 2021https://pubs.acs.org/doi/10.1021/acsenergylett.0c02633https://doi.org/10.1021/acsenergylett.0c02633article-commentaryACS PublicationsCopyright © 2021 American Chemical Society. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views15837Altmetric-Citations142LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail PDF (2 MB) Get e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Electrical properties,Electrocatalysts,Electrochemical cells,Hydrocarbons,Inorganic carbon compounds,Molecules Get e-Alerts

Five silica samples (four precipitated silicas provided by commercial suppliers and one with the MCM-41 structure) have been studied by infrared spectroscopy and by a homemade thermogravimetry-infrared spectrum (TG-IR) setup. The silanol amount, accessibility to water, and different alcohols, and the affinity to water of these various silicas were compared and quantified. TG-IR measurements allowed the precise determination of the integrated molar absorption coefficient of the (nu+delta)OH band, epsilon(nu+delta)OH=(0.16+/-0.01) cm micromol(-1). It is independent of the sample origin and the concentration of silanol groups on silicas. For the precipitated dried samples evacuated at room temperature, the silanol concentration COH varies between 3.6 and 7.0 mmol g(-1). It is 5.3 mmol g(-1) in the case of the MCM-41 sample. Exchange experiments with D2O, followed by back-exchanges with different alcohols (methanol, propan-2-ol, 2-methyl-propan-2-ol, and 3-ethyl-pentan-3-ol) have been followed by infrared spectroscopy. All of the silanols of the MCM-41 sample are accessible to water and alcohol molecules. By contrast, about 20% of the silanols in precipitated samples are not exchanged by D2O (internal silanols). Accessibility decreases with alcohol size; the main effect is relative to methanol. Taking into account the sample specific surface areas and the silanol accessibility to D2O, the surface silanol density of precipitated silicas is close to 8 OH per nm2, at maximum coverage. At variance, the silanol surface density of the MCM silica is much lower, 4 OH per nm2. The TG-IR setup has also been used to determine the amount of water adsorbed on silicas through the intensity of the deltaH2O band. It varies linearly with the concentration of adsorbed water, whatever the silica sample. The integrated molar absorption coefficient of two bands, epsilondeltaH2O=(1.53+/-0.03) cm micromol(-1) and epsilon(nu+delta)H2O=(0.22+/-0.01) cm micromol(-1), have been determined. The number of H2O molecules adsorbed per nm2 has been compared on the five samples under an equilibrium pressure of 13 hPa at room temperature. Taking into account the number of silanols accessible to D2O for each sample, the silica-water affinity has been defined by the H2O/(SiOHsurf) ratio. It is close to 0.8-0.9 for the precipitated samples but lower (0.7) in the case of the MCM one. This result is explained by the more important amount of isolated silanol groups presented by this sample.

Electrochemical CO2 reduction presents a sustainable route to storage of intermittent renewable energy. Ethanol is an important target product, which is used as a fuel additive and as a chemical feedstock. However, electrochemical ethanol production is challenging, as it involves the transfer of multiple electrons and protons alongside C–C bond formation. To date, the most commonly employed and effective catalysts are copper-based materials. This Review presents and categorizes the most efficient and selective Cu-based electrocatalysts, which are divided into three main groups: oxide-derived copper, bimetallics, and copper- and nitrogen-doped carbon materials. Only a few other specific examples fall outside this classification. The catalytic performance of these materials for ethanol production in aqueous conditions is discussed in terms of current density, overpotential, and faradaic efficiency. A critical evaluation of the factors that contribute to high performance is provided to aid the design of more efficient catalysts for selective ethanol formation.

This critical review evaluates the state-of-the-art in propane dehydrogenation catalysis using oxidative and non-oxidative methods, with an emphasis on the sustainability and suitability for process commercialisation.

Abstract Metal promotion in heterogeneous catalysis requires nanoscale-precision architectures to attain maximized and durable benefits. Herein, we unravel the complex interplay between nanostructure and product selectivity of nickel-promoted In 2 O 3 in CO 2 hydrogenation to methanol through in-depth characterization, theoretical simulations, and kinetic analyses. Up to 10 wt.% nickel, InNi 3 patches are formed on the oxide surface, which cannot activate CO 2 but boost methanol production supplying neutral hydrogen species. Since protons and hydrides generated on In 2 O 3 drive methanol synthesis rather than the reverse water-gas shift but radicals foster both reactions, nickel-lean catalysts featuring nanometric alloy layers provide a favorable balance between charged and neutral hydrogen species. For nickel contents >10 wt.%, extended InNi 3 structures favor CO production and metallic nickel additionally present produces some methane. This study marks a step ahead towards green methanol synthesis and uncovers chemistry aspects of nickel that shall spark inspiration for other catalytic applications.

management and nanoscale catalyst design should lead in the near future to more environmentally friendly, energy efficient and selective large-scale technologies for light olefin synthesis.

With the changing media environment and the evolving online atmosphere, traditional media relations strategies (e.g., news release and media kit preparation and distribution) are shifting to practices that are more relevant to a social media environment. The purpose of this article is to define the changing interplay between journalists and public relations practitioners and to analyze the phenomenon of “media catching,” a reversal of the traditional media relations' communication patterns. Given its rapid increase in the past 2 years, journalists are eager to turn the tables and target large numbers of public relations practitioners for specific content for story ideas. The researchers employed content analysis, and the units of analysis were 3,106 reporter requests sent through the Help-A-Reporter-Out (HARO) list and media-related Twitter updates from HARO founder, Peter Shankman, during a 6-month span. Analysis revealed that traditional news outlets more often used the Twitter venue, yet new media outlets preferred the LISTSERV technology. The importance and value of this study for public relations practitioners and scholars are in the study's attempt to profile the trend of media catching, and to discuss the importance of fielding media requests from a variety of news outlets because of the importance of intermedia agenda setting.

A theoretical study of the alkylation reaction of toluene with methanol catalyzed by the acidic Mordenite (Si/Al = 23) is reported. Cluster DFT as well as periodical structure DFT calculations have been performed. Full reaction energy diagrams of the elementary reaction steps that lead to the formation of the three xylene isomers are given. The use of periodical structure calculations allows one to account for zeolite framework electrostatic contributions and steric constraints that take place in zeolitic catalysts. Especially the steric constraint energy contribution has a significant effect on the energies and bond formation paths. The activation energy barrier of p-xylene formation is found to be approximately 20 kJ/mol lower than the corresponding values for the formation of its isomers. Computed host-guest binding energies according to the DFT method need a correction due to the absence of the dispersive interaction with the zeolite wall. Apparent activation energies obtained with this correction are in good agreement with experimental data.

BACKGROUND: Severe complex facial injuries are difficult to reconstruct and require multiple surgical procedures. The potential of performing complex craniofacial reconstruction in one surgical procedure is appealing, and composite face allograft transplantation may be considered an alternative option. The authors describe establishment of the Cleveland Clinic face transplantation program that led them to perform the first U.S. near-total face transplantation. METHODS: In November of 2004, the authors received the world's first institutional review board approval to perform a face transplant in humans. In December of 2008, after a 22-hour operation, the authors performed the first near-total face transplantation in the United States, replacing 80 percent of the patient's traumatic facial deficit with a composite allograft from a brain-dead donor. This largest, and most complex, face allograft in the world included over 535 cm2 of facial skin; functional units of full nose with nasal lining and bony skeleton; lower eyelids and upper lip; underlying muscles and bones, including orbital floor, zygoma, maxilla, alveolus with teeth, hard palate, and parotid glands; and pertinent nerves, arteries, and veins. Immunosuppressive treatment consisted of thymoglobulin, tacrolimus, mycophenolate mofetil, and prednisone. RESULTS: The patient tolerated the procedure and immunosuppression well. At day 47 after transplantation, routine biopsy showed rejection of the graft mucosa without clinical evidence of skin or graft rejection. The patient's physical and psychological recovery went well. The functional outcome has been excellent, including optimal return of breathing through the nose, smelling, tasting, speaking, drinking from a cup, and eating solid foods. CONCLUSION: The functional outcome thus far at 8 months is rewarding and confirms the feasibility of performing complex reconstruction of severely disfigured patients in a single surgical procedure of facial allotransplantation.

Abstract Methanol synthesis by CO 2 hydrogenation is attractive in view of avoiding the environmental implications associated with the production of the traditional syngas feedstock and mitigating global warming. However, there still is a lack of efficient catalysts for such alternative processes. Herein, we unveil the high activity, 100 % selectivity, and remarkable stability for 1000 h on stream of In 2 O 3 supported on ZrO 2 under industrially relevant conditions. This strongly contrasts to the benchmark Cu‐ZnO‐Al 2 O 3 catalyst, which is unselective and experiences rapid deactivation. In‐depth characterization of the In 2 O 3 ‐based materials points towards a mechanism rooted in the creation and annihilation of oxygen vacancies as active sites, whose amount can be modulated in situ by co‐feeding CO and boosted through electronic interactions with the zirconia carrier. These results constitute a promising basis for the design of a prospective technology for sustainable methanol production.