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Does culture eat strategy for breakfast? This paper investigates the interactions among corporate culture, norms, and strategy, in order to better understand this issue and related questions. It first shows, through microfoundations, how the forces that drive toward “culture as shared beliefs and preferences” also cause the emergence of social norms (when these beliefs and preferences are unobservable), with people even endogenously enforcing norms that go againsttheir own beliefs and preferences. The latter effect may cause a disconnect between the organization’s norms and its underlying beliefs and preferences. The paper then makes predictions on the kinds of shared beliefs, preferences, and norms that are likely to emerge, and when they are most likely to emerge. It shows, for example, that social norms are more likely in attractive organizations, for behaviors that have modest personal consequences, and on dimensions along which employees depend on others’ choices to a moderate degree. Building on these insights and on the definition of “strategy as core guidance,” we finally discuss how corporate culture and strategy interact. We show, in particular, how culture is not just an input into strategy but also a direct substitute for strategy and often even a competitor. The results throw light on ways to deal with the “breakfast” issue.

Steam reforming of glycerol is often applied for the generation of green hydrogen; however, here, an effort has been made to produce an efficient syngas composition that can utilize effectively for downstream processes like methanol or FT synthesis. A facile precipitation–deposition approach has been chosen to deposit Pt–Ni nanoparticles on bimodel porous MgAl2O4, synthesized by a template-assisted solvothermal method. These newly developed materials are used successfully for steam reforming of glycerol for syngas production. The MgAl2O4was prepared with different MgO contents between 10 and 30 wt % with a constant Pt (1 wt %) and Ni (5 wt %). All the synthesized materials were characterized in detail to elucidate their physicochemical properties, morphologies, and surface properties via N2sorption, X-ray diffraction (XRD), temperature-programmed reduction (TPR), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma–atomic emission spectroscopy (ICP-AES), and temperature programmed desorption (CO2-TPD) techniques. The catalyst containing 30 wt % MgO produced a syngas ratio of ∼3 and a minimal amount of CO2at 850 °C. The influence of all major parameters was evaluated to maximize the catalyst performance, such as reaction temperature, feed rate, space–time, and feed molar ratios. The catalyst exhibited a high activity with a conversion of glycerol close to unity, and the catalysts were found to be stable in glycerol reforming at high temperatures. To understand the catalyst deactivation, spent catalysts have been further examined through XRD, TEM, XPS, and TGA/DTA analysis. The analysis of the used catalyst confirms the high framework stability, low amount of carbonaceous deposits, and high resistance to metal oxidation.

Operating the Fischer–Tropsch synthesis at high conversion would allow a simpler once-through configuration to be used for small-scale biomass and waste to liquid. The effect of high conversion, and consequently high partial pressure of H2O and low partial pressures of CO and H2, on the stability of nano-sized cobalt crystallites in Pt–Co/Al2O3is investigated.Whilst hydrothermal environments are commonly investigated for deactivation, this is typically done under ‘simulated’ high conversion (low conversion, high partial pressure of water) conditions. Thus, the current study will present the differences between real high conversion and ‘simulated’ high conversion and attempt to decouple the deactivation mechanisms associated with both cases. At conversion levels higher than XCO= 70% for this study (T= 220 °C, p= 20 bar, feed of H2 : CO : N2= 2 : 1 : 3), sintering, cobalt aluminate formation and cobalt oxidation led to rapid deactivation. ‘Simulated’ high conversion is found to cause less cobalt aluminate formation, but more carbon deposition. At very high conversion (XCO> 97%) enhanced reversible deactivation was exhibited due to oxidation and re-reduction of cobalt (shown via in situmagnetometer). A ‘maximum’ conversion seems to exist for a specific cobalt crystallite size caused by its oxidation.

Platinum nanowires (NWs) have been reported to be catalytically active toward the oxygen reduction reaction (ORR). The edge modification of Pt NWs with metals M(M= Au, Ag, or Pd) may have a positive impact on the overall ORR activity by facilitating diffusion of adsorbed oxygen, Oads, and hydroxyl groups, OHads, between the {001} and {111} terraces. In the present study, we have employed classical molecular dynamics simulations to investigate the segregation behavior of Au, Ag, and Pd decorating the edges of Pt NWs. We observe that, under vacuum conditions, Pd prefers to diffuse toward the core rather than stay on the NW surface. Ag and Au atoms are mobile at temperatures as low as 900 K; they remain on the surface but do not appear to be preferentially more stable at edge sites. To effect segregation of Au and Ag atoms toward the edge, we propose annealing in the presence of different reactive gas environments. Overall, our study suggests potential experimental steps required for the synthesis of Pt nanowires and nanoparticles with improved Oadsand OHadsinterfacet diffusion rates and consequently an improved ORR activity.

This paper reviews, discusses, and expands the “core guidance” definition of strategy as “the smallest set of choices to optimally guide (or force) other choices.” It first discusses what this definition contributes relative to the existing proposed definitions. It then considers the extension of this definition to the context of competitive interactions: whether the definition makes sense in that context and what it implies for decisions to be strategic in such context. As part of this analysis, it also uses the definition to explore a new issue: why quantity-based competitive moves might be more strategic than price-based moves.

The stability and mobility of atomic cobalt and of cobalt subcarbonyl species on γ-Al2O3surfaces have been investigated using density functional theory (DFT) with a view to elucidate possible mobile species on these surfaces, which can act as agents in the Ostwald ripening process. The two most stable alumina surfaces γ-Al2O3(100) and γ-Al2O3(110) were probed at different levels of hydration. The stability of cobalt subcarbonyl species on γ-Al2O3(100) at high partial pressure of CO (10 bar) increases with increasing number of CO ligands attached to the central cobalt atom up to Co(CO)3but exhibits a more complex behavior on γ-Al2O3(110). The effect of the hydration level on the stability of cobalt subcarbonyls was investigated. The interpretation of the DFT results in a thermodynamic model shows that at equilibrium the main cobalt subcarbonyl species present on the alumina surface at ca. 500K in the presence of CO are Co(CO)3and Co(CO)4, with Co(CO)3being the dominant species on dry γ-Al2O3(100) and wet γ-Al2O3(110). The fractional coverage of these species on a wetted alumina surface is lower than that on a dry alumina surface. The mobility of surface species was probed by exploring the potential energy surface of the adsorbed species on γ-Al2O3(100) and γ-Al2O3(110) at different hydration levels (ΘOH= 8.5 and 17.7 OH/nm2, respectively). Cobalt subcarbonyl species have a high mobility with activation barriers as low as 0.5 eV. It is argued that these species may contribute to the sintering process.

AbstractThe role of copper in iron based Fischer–Tropsch catalysts was investigated using DFT with χ-Fe5C2(100)0.25as a model surface. The presence of atomic copper on the iron-rich χ-Fe5C2(100)0.25-surface is more favorable than its presence in surface. Nevertheless, the segregation of copper from the surface yielding fcc-Cu remains an exergonic process. Carbon monoxide at a coverage of 2.2 CO per nm2stabilizes atomic copper on this surface. The presence of copper results in the redshift in the stretching frequency of adsorbed CO. The mobility of copper atoms was investigated on χ-Fe5C2(100)0.25in the presence of CO. The hopping frequency is reduced due to the presence of CO, although never enough to avoid formation of fcc-Cu on a shorter time scale than typically required for the formation of hydrocarbons in the Fischer–Tropsch synthesis.

Co3O4as an NH3-oxidation catalyst may transform reversibly to CoO under reaction conditions, even in the presence of excess oxygen. The use of alumina may then result in the formation of cobalt aluminate rendering the catalyst inactive. The formation of cobalt aluminate can be avoided by using ZnAl2O4as a support.

The Fischer Tropsch (FT) synthesis is a complex polymerization reaction characterized by competing intermediates reaction steps. The various termination steps may result in the formation of different product classes, such as olefins, paraffins, alcohols, etc. While high synthesis gas conversion is important; a high selectivity is much desirable, which may result in.improved economics. This mechanistic study further elaborates on the elementary reaction steps for the formation of product compounds in the Fischer-Tropsch synthesis. The effect of space velocity on the products distribution, particularly on the formation of oxygen containing organic product compounds was investigated. The reactions were carried out at industrially relevant conditions on Fe-based catalyst promoted with Cu, K and alumina. The resulting catalyst precursor was characterized using TPR, XRD, BET and SEM/EDX. The alcohol/hydrocarbon ratio remains fairly constant at very high space velocity (i.e. low conversion) where secondary reactions become insignificant. This implied primary formation of alcohols in the Fischer-Tropsch synthesis.

A DFT model of the Fe(100) surface was used to study the dissociation process of H2. The dissociation of H2was considered on a clean surface as well as CO- and C-precovered surfaces. The presence of CO and C is shown to block several sites for hydrogen adsorption, as well as increasing various hydrogen dissociation barriers. At CO and C coverages up to 0.25 ML the main contributor to the barrier increase is the CO−H and C−H repulsion. In these cases, off-symmetry sites will play an important role in the dissociation of the approaching hydrogen molecules. At coverages of 0.5 ML of CO and C, adsorption site blocking occurred, and the dissociation barriers increased to more than 3 times larger values than that of the clean surface. This increase in the barriers will result in a significant decrease in the rate constant of the dissociative H2adsorption process.

Density functional theory calculations on various Fe nanorod morphologies were performed. The resulting excess energies of low coordinated ridge atoms increased with decreasing coordination number. It was found that the square root dependence of excess energy on coordination number is a good first estimate, but that Fe excess energies scale with the coordination number to the power of 0.82 after including surface energy corrections. A simple general model for the size-dependent surface energy of metal nanocrystals has also been derived. Using this model with the obtained parameters for iron showed that the average surface energy of various Fe nanocrystals per surface atom increases as the size of the nanocrystals decreases. On the other hand, the average surface energy normalized with respect to the surface area increased only slightly with a decrease in size.

About a year ago I invited Harrell Fletcher to do an artist's project for the pages of Art Journal.Over time our conversation drifted to the new MFA in social practice he was developing, and it seemed a natural development that it would become the subject and content of his piece. What follows, then, is the record of a conversation among Harrell Fletcher and Sandy Sampson, Eric Steen, Amy Steel, Cyrus Smith, Avalon Kalin, Laurel Kurtz, Katy Asher, and Varinthorn Christopher, the first students in the Portland State University (PSU) program.

A DFT model of the Fe(100) surface was used to study the coadsorption of CO and hydrogen. Various coverages of CO and hydrogen were considered with resulting H:CO ratios ranging from 0.25 to 4. Electrostatic repulsive interactions exist between the adsorbed CO and H as well as an electronic interaction which can have a stabilizing effect on the coadsorbed geometry. A number of geometries at both 0.25 and 0.5 ML of CO coverage are stable in a mixed coadsorbed state as opposed to island formation. This is due to the relative instability of the corresponding compressed CO and H islands. For these mixed states the optimal surface H:CO ratios for ⊖ CO= 0.5 ML and ⊖ CO= 0.25 ML are 1 and 3 respectively.

Possible intermediates in the formation of carbon deposits in cobalt -based Fischer−Tropsch synthesis were investigated using DFT. Larger carbon clusters are more stable than adsorbed atomic carbon, with linear carbon structures being (slightly) more stable than branched structures. The formation of aromatic structures further stabilizes the carbon cluster. A lower estimate for the barrier of diffusion of atomic carbon on flat FCC-Co(111) was estimated to be ca. 42 kJ/mol implying relative high mobility under typical Fischer−Tropsch conditions. A reaction pathway for the formation of graphene on a flat surface is proposed.

The conversion of carbon monoxide with hydrogen was studied on a standard Os on SiO2catalyst at different reaction temperatures, in the range between 200 and 300 °C. Additionally, supported di- and triatomic organometallic Os complexes were tested for their activity in the Fischer-Tropsch synthesis at 220 °C. All compounds showed formation of hydrocarbons, indicating that the organoosmium complexes are indeed active for C-C bond formation. Osmium as Fischer-Tropsch catalyst, however, is approximately 100 times less active compared to ruthenium. Very high methane selectivities (> 90 C-%) were obtained as well as high olefin to paraffin ratios, in particular with the organometallic complexes tested.

Abstract: Gold nanoparticles used in most experiments (1–10 nm) in gold catalysis show varying degrees of reactivity, with particles below 5 nm generally being more reactive. The origin of this activity is a subject of a number of model experiments and theoretical studies on either clusters of a few atoms in size or extended surfaces (smooth or stepped). In the work described here, a classical theory for the variation of the metal workfunction with cluster size, Extended Hückel Theory (EHT) calculations combined with DFT calculations, as well as a carbon monoxide (CO) chemisorption model are combined to develop a relationship between metal particle size and the particle's reactivity towards CO. For gold, it is shown that while the contribution of the d-band hybridization energy to the total CO chemisorption energy is unfavourable for bulk gold, this is not true for gold particles below 5–6 nm. That is, the d-band hybridization energy is negative for small gold particles. This is believed to be explanation of the onset of high reactivity for small gold particles.

The use of nanorods is presented to investigate the properties of low coordination atoms in a metal with an fcc structure. Calculations on nanorods can be performed in a similar manner to surface calculations keeping the efficiency of the 3D periodic plane wave approach. Nanorods with fcc(100) surfaces exposed have been used to calculate the excess energy of low coordination atoms. It was observed that the excess energy per “broken bond” decreases with an increase in the coordination number. The excess energy is further reduced due to relaxation of the surface atoms. Surface magnetization results in a further reduction of the excess energy for magnetic materials, such as Co, but not for nonmagnetic materials, such as Rh. Furthermore, it is shown that the bond strength of the surface atoms with nearest neighboring atoms in surface and bulk increase with a decrease in the coordination.

The present study was undertaken to understand the fundamentals of recycling the tail gas during the Fischer-Tropsch Synthesis with an iron-based catalyst with particular emphasis on the importance of the usage ratio. The usage ratio was ca. 1.4 for the catalyst studied at our reaction conditions (240 °C, 20 bar, 5000 mL/(gcat·h)). The study shows the H2/CO ratio in the recycle gas fed to the reactor depends on both the H2/CO ratio in the fresh feed and the usage ratio of the catalyst. For an H2/CO in the fresh feed higher than the 1.4, the H2/CO ratio in the reactor increases with the increasing recycle ratio whereas the converse is true for H2/CO ratios lower than 1.4. For negligible change in the Fischer-Tropsch selectivity during external recycle, the H2/CO ratio in the fresh feed should match the usage ratio of the catalyst. The presence CO2in this recycled gas did not change the overall CO2selectivity; hence, CO2is regarded as an inert at these conditions.

Supported metal particles play an important role in heterogeneous catalysis. It has been shown lately that the size of the metal crystallites in the supported metal catalysts has a profound effect on the catalytic activity, thus necessitating the need for synthesis methods aimed at a strict control of the metal crystallite size in these catalysts. The classical methods used to synthesize supported metal catalysts typically yield a wide metal crystallite size distribution, and average crystallite sizes which are difficult to control. Suitable techniques have been developed to obtain supported metal catalysts with defined crystallite size distributions, inter alia impregnation of reverse micelle microemulsions, colloid impregnation following reverse micelle precipitation or crystallization, and deposition-precipitation. Using these techniques, a series of supported Ru/γ-Al2O3, Co/SiO2, Fe/γ-Al2O3, Fe/C, and Au/ZnO catalysts have been prepared and characterized.

The hydroxylation of phenol into catechol and hydroquinone with aqueous H2O2(30%) and titanium-substituted molecular sieves (TS-1 and Al-free Ti-Beta) was investigated to understand the role of the zeolite structure, the crystal size, the external surface of the zeolite, and the nature of the solvent on the product selectivity. Comparing Al-free Ti-Beta and TS-1 samples with similar pore lengths, the activity as well as the ratio of catechol to hydroquinone was significantly higher for Al-free Ti-Beta, showing diffusional constraints for the conversion of phenol and geometric constraints for the formation of catechol. The diffusional constraints in the conversion of phenol were confirmed by using small crystallites of TS-1. The role of the external surface of TS-1 in the phenol hydroxylation was investigated by inertization of the external surface, using cycles of low-temperature chemical vapor deposition (CVD) of tetraethoxysilane followed by high-temperature calcination. Consecutive CVD cycles led to a slight increase of the selectivity toward hydroquinone for all tested solvents as well as a reduction of the coke formation in methanol and water. The ratio of hydroquinone to catechol, however, did not change much, indicating that catechol must also be formed inside the pore structure. A kinetic analysis of the reaction data with the parent and surface-inertized TS-1 revealed that the role of the external surface in terms of both activity and selectivity is significant and dependent on the solvent used. A reaction mechanism consistent with the observed enhanced selectivity for hydroquinone in protic solvents is proposed.

The effect of zirconium addition to the catalyst formulation of Co/SiO2Fischer–Tropsch catalysts was investigated. With increasing zirconium content the strong interaction between silica and cobalt is reduced and a somewhat weaker cobalt–zirconium interaction is observed. Therefore the degree of reduction of catalysts, which were reduced at 400°C for 16 h, increases strongly. The cobalt crystallite size increases with increasing zirconium content, leading to smaller cobalt metal surface areas for the freshly reduced catalyst. Cobalt particles can be found in clusters on the silica support. The size of cobalt clusters decreases and thus the number of cobalt particles within a cluster decreases with increasing zirconium content. At steady-state conditions the CO-conversion of the promoted catalyst in the Fischer–Tropsch synthesis increases with increasing zirconium content. The C5+-selectivity and the secondary hydrogenation activity pass a maximum with increasing zirconium content. The observed changes in activity and selectivity are explained in terms of an increase in the amount of metallic cobalt available under reaction conditions, leading to an increased activity, and a decrease in the cobalt cluster size, which diminishes the probability for secondary reactions. Furthermore, it was concluded that secondary double bond isomerization can be catalyzed to some extent by zirconia.

FT CO-hydrogenation on cobalt catalysts has been performed in a well stirred continuously operated slurry reactor with and without addition ofn-octene-1 at different CO partial pressures. Kinetic data have been determined with the help of a mechanistic model. Increasing CO partial pressure inhibits individual reaction steps selectively, in particular associative methane desorption, the steps of chain termination (as paraffins and olefins likewise), whereas in secondary olefin conversion hydrogenation is inhibited drastically, however double bond shift is even promoted. Secondary hydrogenation is concluded to proceed on different sites than chain growth.

Primary product compositions from FT-CO-hydrogenation have been obtained. A kinetic model has been used to calculate rate constants, rates and probabilities of the elemental surface reactions as a function of carbon number from product composition data. Formation of the catalytic system in the initial stage of an experiment is characterized by selectivity changes as related to elemental surface reactions.

The partial oxidation of propene has been studied over iron antimony oxide catalysts in the presence and absence of gaseous oxygen under isothermal and temperature programmed conditions. Temperature programmed reduction (TPR) using propene as reduction gas revealed that for temperatures up to 600°C vacancies are created without phase transition. However, while during the reduction between 250 and 350°C acrolein and CO2 are both formed, exclusively combustion products are formed between 500 and 600°C. At higher temperatures the FeSbO4 rutile structure is destroyed during the reduction process.

The amination of ethanol has been studied using silica-supported cobalt and nickel catalysts prepared by incipient wetness impregnation. Under identical operating conditions, the Co/SiO2 catalyst is considerably more active for ethanol conversion than the Ni/SiO2 catalyst, in spite of the lower measured metal surface area. The higher activity of the Co/SiO2 catalyst combined with its higher selectivity towards the industrially desired lower amines (MEA and DEA) make the metal a promising catalyst. Selectivity to individual ethylamine products (i.e. mono-, di- and triethylamine) is kinetically controlled and a function of the operating parameters as well as of the metal catalyst employed. Temperature programmed reduction (TPR), temperature programmed oxidation (TPO) and hydrogen chemisorption have been used to characterize the physico-chemical differences between the catalysts used in this study.

During the preparation of impregnated cobalt on silica catalysts, different Co-species are formed and these can be detected by means of temperature programmed reduction (TPR). The impregnation step can be explained in terms ofinterfacial coordination chemistry. During the impregnation step, the precursor of surface cobalt silicate is formed by a reaction between surface silanol groups and aqueous cobalt complexes. Therefore, the choice of solvent used in the impregnation step, of the metal salt, and of the carrier is of great importance in the degree of reduction that can be achieved at normal reduction temperatures and catalyst dispersion. Decreasing the polarity of the solvent increases the amount of surface cobalt silicates in the catalyst since the interaction between silanol groups and the cobalt aquocomplex is favored. If the pH of the impregnation solution is above 5 (e.g., using cobalt acetate as the cobalt salt) more cobalt silicates are formed. Drying or low-temperature calcination destroys the precursor of the surface cobalt silicate.

The reductive amination of alcohols using ammonia catalyzed by supported cobalt catalysts has been studied. The catalytic activity for ethanol conversion is shown to be directly proportional to the exposed metal surface area, indicating that the activation of ethanol is metal-catalyzed and no metal-support effects were detected. The selectivity to the mono-, di-, and triethylamine varies with temperature, reactant partial pressures, and extent of reactant conversion generally as expected for a series-type reaction scheme. Both the activation procedure and the type of support also influence selectivity. Increasing the acidity of the support favors the formation of monoethylamine, probably due to disproportionation of diethylamine on the acid sites of the support indicating the bifunctionality of the catalyst.

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