81 resultados para oer


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Open Educational Resources (OER) sind offen lizensierte und frei zugängliche Lehr- und Lernmaterialien, deren Inhalte übernommen, angepasst und unter der gleichen Lizenz weiter verbreitet werden dürfen. Sie stellen einen wichtigen Beitrag zum lebenslangen Lernen dar. In Zusammenhang mit dem wechselnden Rollenverständnis von Wissenschaftlichen Bibliotheken hin zu einem Lernort, gewinnen OER zunehmend an Bedeutung. Diese Arbeit beschäftigt sich mit der Nutzung und dem Umgang von OER in Wissenschaftlichen Bibliotheken. Dargestellt an ausgewählten Beispielen im Zusammenhang mit dem Studium von Flüchtlingen an der KIRON-Universität und deren Zugang zu deutschen Hochschulen. Abschließend gibt diese Arbeit einen Ausblick auf Bereiche, aus denen Bibliotheken zukünftige Dienstleistungen für Ihre Trägereinrichtungen im Bereich der OER entwickeln können. Die Arbeit basiert auf einer Prüfungsleistung vom 14.02.2016 in der Lehrveranstaltung „Aktuelle Entwicklungen im Informationsmanagement“ unter Frau Dr. Ina Blümel.

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Open Educational Resources (OER) are teaching, learning and research materials that have been released under an open licence that permits online access and re-use by others. The 2012 Paris OER Declaration encourages the open licensing of educational materials produced with public funds. Digital data and data sets produced as a result of scientific and non-scientific research are an increasingly important category of educational materials. This paper discusses the legal challenges presented when publicly funded research data is made available as OER, arising from intellectual property rights, confidentiality and information privacy laws, and the lack of a legal duty to ensure data quality. If these legal challenges are not understood, addressed and effectively managed, they may impede and restrict access to and re-use of research data. This paper identifies some of the legal challenges that need to be addressed and describes 10 proposed best practices which are recommended for adoption to so that publicly funded research data can be made available for access and re-use as OER.

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Members of the World Trade Organisation (WTO) are obliged to implement the Agreement on Trade-related Intellectual Property Rights 1994 (TRIPS) which establishes minimum standards for the protection and enforcement of intellectual property rights. Almost two decades after TRIPS was adopted at the conclusion of the Uruguay Round of trade negotiations, it is widely accepted that intellectual property systems in developing and least-developed countries must be consistent with, and serve, their development needs and objectives. In adopting the Development Agenda in 2007, the World Intellectual Property Organisation (WIPO) emphasised the importance to developing and least-developed countries of being able to obtain access to knowledge and technology and to participate in collaborations and exchanges with research and scientific institutions in other countries. Access to knowledge, information and technology is crucial if creativity and innovation is to be fostered in developing and least-developed countries. It is particularly important that developing and least-developed countries give effect to their TRIPS obligations by implementing intellectual property systems and adopting intellectual property management practices that enable them to benefit from knowledge flows and support their engagement in international research and science collaborations. However, developing and least-developed countries did not participate in the deliberations leading to the adoption in 2004 by Organisation for Economic Co-operation and Development (OECD) member countries of the Ministerial Declaration on Access to Research Data from Public Funding, nor have they formulated policies on access to publicly funded research outputs such as those developed by the National Institutes of Health in the United States, the United Kingdom Research Councils or the Australian National Health and Medical Research Council. These issues are considered from the viewpoint of Malaysia, a developing country whose economy has grown strongly in recent years. Lacking an established policy covering access to the outputs of publicly funded research, data sharing and licensing practices continue to be fragmented. Obtaining access to research data requires arrangements to be negotiated with individual data owners and custodians. Given the potential for restrictions on access to impact negatively on scientific progress and development in Malaysia, measures are required to ensure that access to knowledge and research results is facilitated. This paper proposes a policy framework for Malaysia‘s public research universities that recognises intellectual property rights while enabling the open access to research data that is essential for innovation and development. It also considers how intellectual property rights in research data can be managed in order to give effect to the policy‘s open access objectives.

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Using a sociological approach, this study examines China’s reform of open educational resources (OER), which has prompted significant changes to the nation’s higher education sector. Through an analysis of the policy processes that have driven the reform, this study demonstrates that the reform has involved and brought significant changes to its participants as resource administrators, providers, and receivers. By using governmentality as a poststructuralist analytical framework, this study shows the particular ways in which the reform process has been governed and the ways in which the governing practices have changed the conduct of higher education. The study reveals the power relations exercised through the reform and offers a critique of China’s higher education sector.

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Open educational resources (OERs), a disruptive technology, made their appearance in early 2002 as a promising tool for enhancing the quality of and access to education generally and higher education in particular. OERs were also perceived to have the potential to reduce costs by reusing learning materials. This brief draws on a study that reviewed the uptake of OERs and related activities in six institutions in Hong Kong, China; India; Malaysia; Pakistan; and Thailand.

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The oxides of cobalt have recently been shown to be highly effective electrocatalysts for the oxygen evolution reaction (OER) under alkaline conditions. In general species such as Co3O4 and CoOOH have been investigated that often require an elevated temperature step during their synthesis to create crystalline materials. In this work we investigate the rapid and direct electrochemical formation of amorphous nanostructured Co(OH)2 on gold electrodes under room temperture conditions which is a highly active precursor for the OER. During the OER some conversion to crystalline Co3O4 occurs at the surface, but the bulk of the material remains amorphous. It is found that the underlying gold electrode is crucial to the materials enhanced performance and provides higher current density than can be achieved using carbon, palladium or copper support electrodes. This catalyst exhibits excellent activity with a current density of 10 mA cm-2 at an overpotential of 360 mV with a high turnover frequency of 2.1 s-1 in 1 M NaOH. A Tafel slope of 56 mV dec-1 at low overpotentials and a slope of 122 mV dec-1 at high overpotentials is consistent with the dual barrier model for the electrocatalytic evolution of oxygen. Significantly, the catalyst maintains excellent activity for up to 24 hr of continuous operation and this approach offers a facile way to create a highly effective and stable material.

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We discuss rst a method of measuring polarisation at the ILC using the 1{prong hadronic decays of the . We then show in this contribution how a study of the ~sector and particularly use of decay polarisation can oer a very good handle for distinguishing between mSUGRA and a SUSY-GUTs scenario, both of which can give rise to appropriate Dark Matter.

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Formation of an amorphous cobalt based oxygen evolution catalyst called Co-Pi has been recently reported from a neutral phosphate buffer solution containing Co2+. But the concentration of Co2+ is as low as 0.5 mM due to poor solubility of a cobalt salt in phosphate medium. In the present study, a cobalt acetate based oxygen evolution catalyst (Co-Ac) is prepared from a neutral acetate buffer solution, where the solubility of Co2+ is very high (>100 times in comparison with phosphate buffer solution). The Co-Ac possesses better catalytic activity than the Co-Pi with an additional advantage of easy bulk scale preparation. The comparative studies on the oxygen evolution reaction (OER) activity of Co-Ac and Co-Pi in phosphate and acetate buffer electrolytes reveal that the Co-Ac exhibits enhanced synergistic catalytic activity in phosphate solution, probably due to partial substitution of acetate in the catalyst layer by phosphate, resulting in the formation of a Co-Ac-Pi catalyst.

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The preparation of ZnO nanorod films decorated with cobalt-acetate (CoAc) electrocatalyst and its activity for photoelectrolysis of water have been demonstrated. The photochemically prepared CoAc catalyst is chemically and morphologically similar to the electrochemically prepared CoAc catalyst. The on-set potential of oxygen evolution reaction is lower on CoAc-ZnO photoanode in relation to bare ZnO photoanode. There is a three to four fold increase in photooxidation current of OER due to the presence of CoAc co-catalyst on ZnO. Thus, the photochemically prepared CoAc on ZnO is an alternative and efficient co-catalyst for photoelectrochemical oxygen evolution reaction. The enhancement in photocatalytic activity of ZnO by the CoAc catalyst photochemically deposited from acetate buffer solution is significantly greater than the cobalt-phosphate (CoPi) co-catalyst deposited from phosphate buffer solution. (C) The Author(s) 2015. Published by ECS. All rights reserved.

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Large-scale production of hydrogen gas by water electrolysis is hindered by the sluggish kinetics of oxygen evolution reaction (OER) at the anode. The development of a highly active and stable catalyst for OER is a challenging task. Electrochemically prepared amorphous metal-based catalysts have gained wide attention after the recent discovery of a cnbalt-phosphate (Co-Pi) catalyst: Herein, an amorphous iridium-phosphate (Ir-Pi) is investigated as an oxygen evolution catalyst. The catalyst is prepared by the anodic polarization of carbon paper electrodes in neutral phosphate buffer solutions containing IrCl3. The Ir-Pi film deposited on the substrate has significant amounts of phosphate and It centers in an oxidation state higher than +4. Phosphate plays a significant role in the deposition of the catalyst and also in its activity toward OER. The onset potential of OER on the Ir-Pi is about 150 mV lower in comparison with the Co-Pi under identical experimental conditions. Thus, Ir-Pi is a promising catalyst for electrochemical oxidation of water.

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We report a unique, single source precursor Prussian blue (iron(III) ferrocyanide (Fe-4(III)Fe-II(CN)(6)](3))) for the synthesis of Fe/Fe3C nanoparticle encapsulated N-doped graphitic layers and bamboo-like graphitic nanotubes. Hollow N-doped graphite (N-HG) nanostructures are obtained when the encapsulated nanostructures are treated with an acid. Both the encapsulated nanostructures and N-HG are shown to be applicable as bi-functional electrocatalysts for oxygen reduction (ORR) and oxygen evolution reactions (OER). The ORR activity is shown to be improved for N-HG and is comparable to commercial Pt/C. On the other hand, encapsulated nanostructures exhibit OER activity with long-term stability comparable to commercial RuO2.

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We report a unique, single source precursor Prussian blue (iron(III) ferrocyanide (Fe-4(III)Fe-II(CN)(6)](3))) for the synthesis of Fe/Fe3C nanoparticle encapsulated N-doped graphitic layers and bamboo-like graphitic nanotubes. Hollow N-doped graphite (N-HG) nanostructures are obtained when the encapsulated nanostructures are treated with an acid. Both the encapsulated nanostructures and N-HG are shown to be applicable as bi-functional electrocatalysts for oxygen reduction (ORR) and oxygen evolution reactions (OER). The ORR activity is shown to be improved for N-HG and is comparable to commercial Pt/C. On the other hand, encapsulated nanostructures exhibit OER activity with long-term stability comparable to commercial RuO2.

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A composite of manganese oxide and reduced graphene oxide (rGO) is prepared in a single step electrochemical reduction process in a phosphate buffer solution for studying as an electrocatalyst for the oxygen evolution reaction (OER). The novel composite catalyst, namely, MnOx-Pi-rGO, is electrodeposited from a suspension of graphene oxide (GO) in a neutral phosphate buffer solution containing KMnO4. The manganese oxide incorporates phosphate ions and deposits on the rGO sheet, which in turn is formed on the substrate electrode by electrochemical reduction of GO in the suspension. The OER is studied with the MnOx-Pi-rGO catalyst in a neutral phosphate electrolyte by linear sweep voltammetry. The results indicate a positive influence of rGO in the catalyst. By varying the ratio of KMnO4 and GO in the deposition medium and performing linear sweep voltammetry for the OER, the optimum composition of the deposition medium is obtained as 20 mM KMnO4 + 6.5% GO in 0.1 M phosphate buffer solution of pH 7. Under identical conditions, the MnOx-Pi-rGO catalyst exhibits 6.2 mA cm(-2) OER current against 2.9 mA cm(-2) by MnOx-Pi catalyst at 2.05 V in neutral phosphate solution. The Tafel slopes measured for OER at MnOx-Pi and MnOx-Pi-rGO are similar in magnitude at about 0.180 V decade(-1). The high Tafel slopes are attributed to partial dissolution of the catalyst during oxygen evolution. The O-2 evolved at the catalyst is measured by the water displacement method and the positive role of rGO on catalytic activity of MnOx-Pi is demonstrated.

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This dissertation is mainly divided into two sub-parts: organometallic and bioinorganic/materials projects. The approach for the projects involves the use of two different multinucleating ligands to synthesize mono- and multinuclear complexes. Chapter 2 describes the synthesis of a multinucleating tris(phosphinoaryl)benzene ligand used to support mono-nickel and palladium complexes. The isolated mononuclear complexes were observed to undergo intramolecular arene C¬–H to C–P functionalization. The transformation was studied by nuclear magnetic resonance spectroscopy and X-ray crystallography, and represents a rare type of C–H functionalization mechanism, facilitated by the interactions of the group 10 metal with the arene π–system.

Chapter 3 describes the construction of multinickel complexes supported by the same triphosphine ligand from Chapter 2. This chapter shows how the central arene in the ligand’s triarylbenzene framework can interact with dinickel and trinickel moieties in various binding modes. X-ray diffraction studies indicated that all compounds display strong metal–arene interactions. A cofacial triangulo nickel(0) complex supported by this ligand scaffold was also isolated and characterized. This chapter demonstrates the use of an arene as versatile ligand design element for small molecular clusters.

Chapter 4 presents the syntheses of a series of discrete mixed transition metal Mn oxido clusters and their characterization. The synthesis of these oxide clusters displaying two types of transition metals were targeted for systematic metal composition-property studies relevant to mixed transition metal oxides employed in electrocatalysis. A series of heterometallic trimanganese tetraoxido cubanes capped with a redox-active metal [MMn3O4] (M = Fe, Co, Ni, Cu) was synthesized starting from a [CaMn3O4] precursor and structurally characterized by X-ray crystallography and anomalous diffraction to conclusively determine that M is incorporated at a single position in the cluster. The electrochemical properties of these complexes were studied via cyclic voltammetry. The redox chemistry of the series of complexes was investigated by the addition of a reductant and oxidant. X-ray absorption and electron paramagnetic resonance spectroscopies were also employed to evaluate the product of the oxidation/reduction reaction to determine the site of electron transfer given the presence of two types of redox-active metals. Additional studies on oxygen atom transfer reactivities of [MMn3O4] and [MMn3O2] series were performed to investigate the effect of the heterometal M in the reaction rates.

Chapter 5 focuses on the use of [CoMn3O4] and [NiMn3O4] cubane complexes discussed in Chapter 4 as precursors to heterogeneous oxygen evolution reaction (OER) electrocatalysts. These well-defined complexes were dropcasted on electrodes with/without heat treatment, and the OER activities of the resulting films were evaluated. Multiple spectroscopic techniques were performed on the surface of the electrocatalysts to gain insight into the structure-function relationships based on the heterometallic composition. Depending on film preparation, the Co-Mn-oxide was found to change metal composition during catalysis, while the Ni-Mn oxide maintained the NiMn3 ratio. These studies represent the use of discrete heterometallic-oxide clusters as precursors for heterogeneous water oxidation catalysts.

Appendix A describes the ongoing effort to synthesize a series of heteromultimetallic [MMn3X] clusters (X = O, S, F). Complexes such as [ZnMn3O], [CoMn3O], [Mn3S], and [Mn4F] have been synthesized and structurally characterized. An amino-bis-oxime ligand (PRABO) has been installed on the [ZnMn3O] cluster. Upon the addition of O2, the desymmetrized [ZnMn3O] cluster only underwent an outer-sphere, one-electron oxidation. Efforts to build and manipulate other heterometallic [MMn3X] clusters are still ongoing, targeting O2 binding and reduction. Appendix B summarizes the multiple synthetic approaches to build a [Co4O4]-cubane complex relevant to heterogeneous OER electrocatalysis. Starting with the tricobalt cluster [LCo3(O2CR)3] and treatment various strong oxidants that can serve as oxygen atom source in the presence Co2+ salt only yielded tricobalt mono–oxo complexes. Appendix C presents the efforts to model the H-cluster framework of [FeFe]-hydrogenase by incorporating a synthetic diiron complex onto a protein-supported or a synthetic ligand-supported [Fe4S4]-cluster. The mutant ferredoxin with a [Fe4S4]-cluster and triscarbene ligand have been characterized by multiple spectroscopic techniques. The reconstruction of an H-cluster mimic has not yet been achieved, due to the difficulty of obtaining crystallographic evidence and the ambiguity of the EPR results.

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Metal-aire baterietarako grafenoan oinarritutako aire elektrodoaren diseinua eta fabrikazioa. Hasteko, grafenoan eutsitako katalizatzaileen sintesia eta haien analisi elektrokimikoa 'Rotating Disk Electrode' teknikaren bidez burutu dira. Ondoren, katalizatzaile eta egitura desberdineko elektrodoen fabrikazioa eta jokaeraren analisia egin dira bifuntzionala den geruza bikoitzeko elektrodoa lortzeko.