478 research outputs found

    Enhanced Ammonia Oxidation Catalysis by a Low-Spin Iron Complex Featuring Cis Coordination Sites

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    The goal of using ammonia as a solar fuel motivates the development of selective ammonia oxidation (AO) catalysts for fuel cell applications. Herein, we describe Fe-mediated AO electrocatalysis with [(bpyPy₂Me)Fe(MeCN)₂]²⁺, exhibiting the highest turnover number (TON) reported to date for a molecular system. To improve on our recent report of a related iron AO electrocatalyst, [(TPA)Fe(MeCN)₂]²⁺ (TON of 16), the present [(bpyPy₂Me)Fe(MeCN)₂]²⁺ system (TON of 149) features a stronger-field, more rigid auxiliary ligand that maintains cis-labile sites and a dominant low-spin population at the Fe(II) state. The latter is posited to mitigate demetalation and hence catalyst degradation by the presence of a large excess of ammonia under the catalytic conditions. Additionally, the [(bpyPy₂Me)Fe(MeCN)₂]²⁺ system exhibits a substantially faster AO rate (ca. 50×) at significantly lower (∼250 mV) applied bias compared to [(TPA)Fe(MeCN)₂]²⁺. Electrochemical data are consistent with an initial E₁ net H-atom abstraction step that furnishes the cis amide/ammine complex [(bpyPy₂Me)Fe(NH₂)(NH₃)]²⁺, followed by the onset of catalysis at E₂. Theoretical calculations suggest the possibility of N–N bond formation via multiple thermodynamically plausible pathways, including both reductive elimination and ammonia nucleophilic attack. In sum, this study underscores that Fe, an earth-abundant metal, is a promising metal for further development in metal-mediated AO catalysis by molecular systems

    Social Entrepreneurship—Building Sustainability Through Business Models and Measurement of Social Impact

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    Social entrepreneurshipSocial entrepreneurship is gaining unprecedented momentum in the recent years and it is overwhelming to learn how social entrepreneurs are able to create both social and economic value overcoming all odds and sustain and grow their ventures. Social enterprise can be a for-profit or a not-for- profit venture in their constitution. This research study presents a comparative case analysis of four social ventures two of them are not-for-profit organisations and depend mainly on philanthropic partners for funding. The other two are for-profit social venturesNot-for-profit Social venture and create products and services which are commercially viable. Three of the founders are Ashoka fellows and one is a national award winning social entrepreneur, all based in India. Irrespective of the nature of enterprise, developing a viable business modelBusiness model is crucial for the sustainabilitySustainability of the venture. Analysis of these organisations’ business models reveals different patterns. The findings suggest that successful social entrepreneurial organisations proactively create their own ways to partner with multiple stakeholders who share their social visionVision ; deploy resources effectively as an integral part of the business model; and integrate the target group into the social value network

    The global field of multi-family offices: An institutionalist perspective

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    We apply the notion of the organisational field to internationally operating multi-family offices. These organisations specialise on the preservation of enterprising and geographically dispersed families’ fortunes. They provide their services across generations and countries. Based on secondary data of Bloomberg’s Top 50 Family Offices, we show that they constitute a global organisational field that comprises two clusters of homogeneity. Clients may decide between two different configurations of activities, depending on their preferences regarding asset management, resource management, family management, and service architecture. The findings also reveal that multi-family offices make relatively similar value propositions all over the world. The distinctiveness of the clusters within the field is not driven by the embeddedness of the multi-family offices in different national environments or their various degrees of international experience. Rather, it is weakly affected by two out of four possible value propositions, namely the exclusiveness and the transparency of services

    Entrepreneurial Value Creation in the Cloud: Exploring the Value Dimensions of the Business Model

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    Part 5: Research in ProgressInternational audienceCloud computing’s potential in creating and capturing business value is being increasingly acknowledged. Existing empirical studies of business value in cloud computing have focused on user organizations and large enterprises with legacy systems. Acknowledging the innovation opportunities created by cloud, we study entrepreneurial cloud service providers. In this paper we conduct an exploratory study of six cloud-based start-up firms in India. We examine the value dimensions of the business model concept to study entrepreneurial value creation in the cloud. We find that cloud is a key resource in the structural configuration of their business model and enables the value proposition

    Electrocatalytic Ammonia Oxidation Mediated by a Polypyridyl Iron Catalyst

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    Electrocatalytic ammonia oxidation (AO) mediated by iron(II) tris(2-pyridylmethyl)amine (TPA) bis-ammine triflate, [(TPA)Fe(NH₃)₂]OTf₂, is reported. Interest in (electro)catalytic AO is growing rapidly, and this report adds a first-row transition metal (iron) complex to the known Ru catalysts recently reported. The featured system is well behaved and has been studied in detail by electrochemical methods. Cyclic voltammetry experiments in the presence of ammonia indicate an onset potential corresponding to ammonia oxidation at 0.7 V vs Fc/Fc⁺. Controlled potential coulometry (CPC) at an applied bias of 1.1 V confirms the generation of 16 equiv of N₂ with a Faradaic efficiency for N₂ of ∼80%. Employing ¹⁵NH₃ yields exclusively ³⁰N₂, demonstrating the conversion of ammonia to N₂. A suite of electrochemical studies is consistent with an initial EC step that generates an Fe^(III)–NH₂ intermediate (at 0.4 V) followed by an anodically shifted catalytic wave. The data indicate a rate-determining step that is first order in both [Fe] and [NH₃] and point to a fast catalytic rate (k_(obs)) of ∼10⁷ M⁻¹·s⁻¹ as computed by foot of the wave analysis (FOWA)

    Electrocatalytic Ammonia Oxidation Mediated by a Polypyridyl Iron Catalyst

    Get PDF
    Electrocatalytic ammonia oxidation (AO) mediated by iron(II) tris(2-pyridylmethyl)amine (TPA) bis-ammine triflate, [(TPA)Fe(NH₃)₂]OTf₂, is reported. Interest in (electro)catalytic AO is growing rapidly, and this report adds a first-row transition metal (iron) complex to the known Ru catalysts recently reported. The featured system is well behaved and has been studied in detail by electrochemical methods. Cyclic voltammetry experiments in the presence of ammonia indicate an onset potential corresponding to ammonia oxidation at 0.7 V vs Fc/Fc⁺. Controlled potential coulometry (CPC) at an applied bias of 1.1 V confirms the generation of 16 equiv of N₂ with a Faradaic efficiency for N₂ of ∼80%. Employing ¹⁵NH₃ yields exclusively ³⁰N₂, demonstrating the conversion of ammonia to N₂. A suite of electrochemical studies is consistent with an initial EC step that generates an Fe^(III)–NH₂ intermediate (at 0.4 V) followed by an anodically shifted catalytic wave. The data indicate a rate-determining step that is first order in both [Fe] and [NH₃] and point to a fast catalytic rate (k_(obs)) of ∼10⁷ M⁻¹·s⁻¹ as computed by foot of the wave analysis (FOWA)

    A Proposal of Business Model Design Parameters for Future Internet Carriers

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    Future Internet evolution requires innovative strategic stances and the design of original business models from actors involved in the ecosystem. The study focuses on Internet Carriers, recently striving to make their business sustainable, and proposes to enclose in a single reference framework all the critical levers, either consolidated or innovative, such actors can employ in order to design their value proposition, value network integration, and financial configuration. The framework grounds its findings on multiple case studies, and, by presenting an insightful list of business model parameters for Carriers, sheds light on key emerging strategic and tactical trends in the Internet interconnections market

    Development of a data-driven business model transformation tool

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    Rapidly changing environments and customer demands force companies to transform their business models in ever shorter periods of time. However, existing approaches like the business model canvas and corresponding tools mainly focus on documentation on a strategic level and do not actively support the business model transformation process from a current state towards a target state. To address this problem, we derive requirements for a business model transformation tool. We translate these requirements into design principles and present a toolset for data-driven business model transformation. This toolset enables companies to extract status quo business models from existing operational information systems. Furthermore, it allows the representation of explicit relationships between the different value dimensions of a business model and enables quantifying the impact of changes. The result of this paper is a set of requirements, design principles as well as a tool instantiation, which can actively support the business model transformation process

    The Business Model: Recent Developments and Future Research

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    This article provides a broad and multifaceted review of the received literature on business models in which the authors examine the business model concept through multiple subject-matter lenses. The review reveals that scholars do not agree on what a business model is and that the literature is developing largely in silos, according to the phenomena of interest of the respective researchers. However, the authors also found emerging common themes among scholars of business models. Specifically, (1) the business model is emerging as a new unit of analysis; (2) business models emphasize a system-level, holistic approach to explaining how firms “do business”; (3) firm activities play an important role in the various conceptualizations of business models that have been proposed; and (4) business models seek to explain how value is created, not just how it is captured. These emerging themes could serve as catalysts for a more unified study of business models
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