58 research outputs found

    Below the 12-vertex: 10-vertex carborane anions as non-corrosive, halide free, electrolytes for rechargeable Mg batteries

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    The development of practical Mg based batteries is limited by the lack of a library of suitable electrolytes. Recently a 12-vertex closo-carborane anion based electrolyte has been shown to be the first electrolyte for Mg based batteries, which is both non-corrosive and has high electrochemical stability (+3.5 V vs. Mg0/2+). Herein we show that smaller 10-vertex closo-carborane anions also enable electrolytes for Mg batteries. Reduction of the trimethylammonium cation of [HNMe31+][HCB9H91-] with elemental Mg yields the novel magnesium electrolyte [Mg2+][HCB9H91-]2. The electrolyte displays excellent electrochemical stability, is non-nucleophilic, reversibly deposits and strips Mg, and is halide free. This discovery paves the way for the development of libraries of Mg electrolytes based on more cost effective 10-vertex closo-carborane anions

    Impact of sample pretreatment on the measured element concentrations in the bivalve Arctica islandica

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    Correlating metal to calcium (Me/Ca) ratios of marine biogenic carbonates, such as bivalve shells, to environmental parameters has led to contradictory results. Biogenic carbonates represent complex composites of organic and inorganic phases. Some elements are incorporated preferentially into organic phases, and others are incorporated into inorganic phases. Chemical sample pretreatment to remove the organic matrix prior to trace element analysis may increase the applicability of the investigated proxy relationship, though its efficiency and side effects remain questionable. We treated inorganic calcium carbonate and bivalve shell powder (Arctica islandica) with eight different chemical treatments including H2O2, NaOH, NaOCl, and acetone and analyzed the effects on (1) Me/Ca ratios (Sr/Ca, Mg/Ca, Ba/Ca, and Mn/Ca), (2) organic matter (≈N) content, and (3) mineralogical composition of the calcium carbonate. The different treatments (1) cause element and treatment specific changes of Me/Ca ratios, (2) vary in their efficiency to remove organic matter, and (3) can even alter the phase composition of the calcium carbonate (e.g., formation of Ca(OH)2 during NaOH treatment). Among all examined treatments there were none without any side effects. In addition, certain Me/Ca changes we observed upon chemical treatment contradict our expectations that lattice-bound elements (Sr and Ba) should not be affected, whereas non-lattice-bound elements (Mg and Mn) should decrease upon removal of the organic matrix. For instance, we observe that NaOCl treatment did not alter Sr/Ca ratios but caused unexpected changes of the Mg/Ca ratios. The latter demonstrates that the buildup of complex biogenic composites like the shell of Arctica islandica are still poorly understood

    ChemInform Abstract: New Routes to Carboranes

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    Nuclear magnetic resonance data of CH14B9 −

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    ChemInform Abstract: New Synthetic Routes to B4H10 and B5H9.

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    ChemInform Abstract: B6H14, a Dimeric B3H7?

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    Die Corporate Governance von Tochtergesellschaften in Multinationalen Unternehmen - Theoretische Analyse und Empirische Erkenntnisse aus Europa

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    Die Arbeit behandelt die Corporate Governance von Tochtergesellschaften in Konzernen (Subsidiary Corporate Governance; SCG), die durch Entwicklungen in der Unternehmenspraxis der letzten Jahre zunehmend an Bedeutung fĂŒr Manager und Forscher gewinnt. Die Arbeit spricht erstmals umfassend eine Thematik an, die bisher in der Literatur nur vereinzelt neben dem Bereich Corporate Governance von Konzernmuttergesellschaften, bzw. Einzelunternehmen (klassische Corporate Governance), behandelt worden ist und leistet einen sowohl theoretischen (deduktiven) als auch empirischen (induktiven) Forschungsbeitrag. HierfĂŒr werden im ersten, theoretischen Teil der Arbeit die gĂ€ngigen Theorien und die empirische Literatur der klassischen Corporate Governance auf SCG angewandt, der Themenbereich wird identifiziert, charakterisiert und abgegrenzt, und die VerfĂŒgbarkeit und EffektivitĂ€t von Mechanismen klassischer Corporate Governance fĂŒr SCG abgeleitet. Auf dieser Basis leitet der zweite Teil der Arbeit ein theoretisches Rahmenkonzept aus Agentur- und Kontingenztheorie ab, wendet es auf SCG an und schlussfolgert und beschreibt die der SCG zugrunde liegende Agenturproblematik, die grundsĂ€tzlich mit der der klassischen Corporate Governance vergleichbar ist. Die dadurch gewonnenen Erkenntnisse werden genutzt, um eine Serie von Hypothesen ĂŒber Governance-Mechanismen von SCG und deren Kontingenzvariablen abzuleiten, wofĂŒr auch verwandte, angrenzende Themenbereiche, insbesondere die Organisationsliteratur, herangezogen werden. Die Hypothesen werden mit einem Datensatzes von multinationalen Unternehmen getestet und mit Erkenntnissen aus einer Reihe von halbstrukturierten Interviews kombiniert. Der Datensatz wurde im Rahmen eines Forschungsprojektes des International Institute for Management Development (IMD) in Lausanne, Schweiz, im Zeitraum Februar bis April 2005 erhoben (PrimĂ€rdaten). Er umfasst 153 Fragebögen von Managern multinationaler Unternehmen mit Sitz in Europa, wovon 68% der Konzernmutter- und 32% einer Konzerntochtergesellschaft angehören. Die empirischen Daten werden durch deskriptive statistische Analysen und ausfĂŒhrliche Korrelations- und Regressionsanalysen untersucht und mit Erkenntnissen aus den Interviews vergleicht und ergĂ€nzt, die durch Inhaltsanalysen gewonnen wurden. Zu den Kernergebnissen der Arbeit gehören die folgenden Erkenntnisse: Die Mechanismen klassischer Corporate Governance sind fĂŒr SCG grĂ¶ĂŸtenteils inexistent oder wenn existent, dann ineffizient, weswegen in der Praxis eine Reihe originĂ€rer SCG-Mechanismen Anwendung findet und zunehmend an Bedeutung gewinnt. Dazu gehören SCG-Kodizes und konzerninterne Kontrollorgane und Informationssysteme. Diese werden in der Praxis durch weitere Mechanismen ergĂ€nzt, die in der klassischen Corporate Governance-Literatur als zentrale Governance-Mechanismen angesehen werden, in Bezug auf Tochtergesellschaften jedoch dem Forschungsgebiet Konzernsteuerung/-kontrolle zugeordnet werden (z.B. finanzielle Anreize, individuelle VertrĂ€ge). Diese Erkenntnis deutet auf eine multidimensionale, interdisziplinĂ€re Natur des Themenfelds SCG hin, wie dies auch fĂŒr klassische Corporate Governance der Fall ist. Die Ergebnisse zeigen zudem, dass SCG eine strategische Bedeutung fĂŒr multinationale Unternehmen in der Praxis hat und teilweise stark kontextabhĂ€ngig ist, insbesondere in Bezug auf Kontingenzvariablen aus der Umgebung der Tochtergesellschaft (z.B. das rechtliche Umfeld der Tochtergesellschaft). Im Zusammenhang mit der Diskussion der Erkenntnisse aus dem industrie- und lĂ€nderĂŒbegreifenden Datensatz werden zudem Empfehlungen fĂŒr das Konzernmanagement in der Praxis abgeleitet.This thesis deals with the corporate governance of subsidiaries in groups (subsidiary corporate governance; SCG), which has become increasingly important for managers and researchers, particularly through the last years’ developments around corporate governance in practice. In doing so, the thesis investigates for the first time comprehensively a topic, which literature has addressed only sporadically so far next to the corporate governance of group parent companies or individual companies, respectively (classical corporate governance). The first part of the thesis employs established theories and empirical findings from classical corporate governance on SCG, identifies, characterizes and delineates the topic and deduces the availability and effectiveness of mechanisms of classical corporate governance for SCG. On this basis, the second part of the thesis derives a theoretical framework of Agency and Contingency theory, applies it to SCG and deduces and describes the Agency Problem underlying SCG, which is in principle comparable to classical corporate governance. The findings from these analyses are then used to deduce a series of hypotheses on governance mechanisms of SCG and their shaping factors (contingencies), thereby also making use of literature from adjacent, related research fields, in particular organizational literature. A dataset from multinational corporations is used to test these hypotheses and the findings are combined with those from a series of semi-structured interviews. The dataset was surveyed in the course of a research project at the International Institute for Management Development (IMD) in Lausanne, Switzerland, in the time period from February until April 2005 (primary data). It contains 153 questionnaires from managers of multinational groups with headquarters in Europe. 68% of these managers are located at the group headquarters and 32% at a subsidiary. The empirical data is examined by descriptive statistical analyses and extensive correlation and regression analyses, and compared to and amended with findings from the interviews obtained through qualitative content analysis. The core findings of this investigation include: The governance mechanisms of classical corporate governance are, for the most part, inexistent for SCG, or existent but ineffective. For this reason, multinational corporations in practice apply a series of governance mechanisms unique to SCG, which become increasingly important. These include SCG codes of conduct/corporate governance, group-internal control bodies and information systems. They are amended with further mechanisms considered central governance mechanisms in classical corporate governance literature, but allocated to the field of group management and control in connection with subsidiaries (e.g. financial incentives, individual contracts). This conclusion points at a multidimensional, interdisciplinary nature of the topic SCG, comparable to classical corporate governance. The findings of the thesis also show that SCG is of strategic importance to multinational corporations in practice and that it is partly highly contextual, in particular with regards to contingencies from the environment of the subsidiary (e.g. the legal corporate governance environment). In connection with the discussion of results from the analysis of the cross-country and cross-industry dataset, the investigation also concludes recommendations for multinational corporations in practice
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