385 research outputs found

    Novel thin film polymer foaming technique for low and ultra low-k dielectrics

    Get PDF
    The results presented show a novel route for the preparation of thin ultra-low-k polymer films based on commercial and "non-exotic" (non-expensive) polyimide by a foaming technique. Dependent on the glass transition temperature of the polyimide mechanically and thermally stable (> 300 °C) films having porosities of ca. 40 % and k-values below 2.0 are formed. A further reduction into the ultra low k region may be accomplished by tailoring the shape of the pores from spherical into disc-like void

    Dielectric and polarization experiments in high loss dielectrics: a word of caution

    Full text link
    The recent quest for improved functional materials like high permittivity dielectrics and/or multiferroics has triggered an intense wave of research. Many materials have been checked for their dielectric permittivity or their polarization state. In this report, we call for caution when samples are simultaneously displaying insulating behavior and defect-related conductivity. Many oxides containing mixed valent cations or oxygen vacancies fall in this category. In such cases, most of standard experiments may result in effective high dielectric permittivity which cannot be related to ferroelectric polarization. Here we list few examples of possible discrepancies between measured parameters and their expected microscopic origin

    Allying knowledge integration and co-production for knowledge legitimacy and usability: The Amazonian SISA policy and the Kaxinawá Indigenous people case.

    Get PDF
    Environmental policies that aim to enhance nature conservation, biodiversity, and well-being of Indigenous Peoples and Local Communities (IPLC) rely on knowledge integration and co-production processes that include both science and Indigenous and local knowledge (ILK) systems. While these processes are expected to safeguard the diversity of knowledge systems, uneven power relations among participants often prevent them from achieving this which can affect the legitimacy and usability of the outcomes of these processes. Using a case study in the Acre state (Brazil), where policy practitioners implemented the REDD+policy System of Incentives for Ecosystem Services in the Brazilian Kaxinawá Nova Olinda Indigenous Land, we investigate how participants manage challenges to safeguard knowledge diversity and usability during policy assessment and planning. Our findings show how, despite the use of participatory approaches, knowledge diversity ended up being compromised because policy practitioners were insufficiently attentive to power asymmetries and their implications. This, however, did not negatively affect the usability of the knowledge outcomes. Rather than focusing on the perfection of participatory methods, we call for a practical ethics that relies on culturally and ethically sensitive dialogues and that include continuous reflection. Such reflection will enable adaptation and improvisation to be able to respond to emerging power dynamics in an adequate and timely manner, thereby ensuring both the legitimacy and the usability of the outcomes of knowledge integration and co-production

    Herstelmaatregelen in heideterreinen; invloed op de fauna

    Get PDF
    Aanleiding voor deze publicatie zijn de resultaten van het onderzoek naar de effecten van herstelmaatregelen op dieren van het heidelandschap. De afgelopen jaren werd steeds duidelijker dat het onderzoek en de toepassing daarvan moeten worden opgeschaald naar het niveau van het landschap. Dat is ook hier zichtbaar geworden: het gaat niet alleen over de droge en de natte heide, maar ook over vennen en over struwelen en bosranden. Kortom: het gaat over het complete heidelandschap, met al zijn variatie en (geleidelijke of abrupte) overgangen. En juist bij zo’n divers en samenhangend landschap is de fauna gebaa

    Including diverse knowledges and worldviews in environmental assessment and planning: the Brazilian Amazon Kaxinawá Nova Olinda Indigenous Land case.

    Get PDF
    The concepts of 'ecosystem services' (ES) and 'nature's contributions to people' (NCP) inform environmental frameworks that set out to include Indigenous and Local Knowledge systems (ILK) and worldviews in policy and planning processes. These frameworks aim to enhance biodiversity conservation and human well-being in a legitimate and effective way. In this article, we explore how the concept of People's Contributions to Nature (PCN) is complementary to NCP. We use it to investigate challenges that planners and locals face in realizing the legitimate inclusion of diverse knowledges and worldviwes that account for people and ecosystems in a relational way. We introduce a case study where planners drew on ES and NCP and used participatory methods to implement a REDD+ policy in the Kaxinawá Nova Olinda Indigenous Land (Acre-Brazil). We find that both Kaxinawás and planners emphasize both NCP and PCN in their discourses. Nevertheless, differences between knowledge systems and disciplines, uneven power relations between Kaxinawás and planners, and an underconsideration of PCN by global frameworks challenge the legitimate inclusion of the Kaxinawá knowlege and worldviews to craft assessment and planning. We conclude that by explicitly addressing these challenges, science-policy interfaces can further advance knowledge legitimacy and policy effectiveness

    Organisational design for an integrated oncological department

    Get PDF
    OBJECTIVE: The outcomes of a Strength, Weakness, Opportunities and Threat (SWOT) analysis of three Integrated Oncological Departments were compared with their present situation three years later to define factors that can influence a successful implementation and development of an Integrated Oncological Department in- and outside (i.e. home care) the hospital. RESEARCH DESIGN: Comparative Qualitative Case Study. METHODS: Auditing based on care-as-usual norms by an external, experienced auditing committee. RESEARCH SETTING: Integrated Oncological Departments of three hospitals. RESULTS: Successful multidisciplinary care in an integrated, oncological department needs broad support inside the hospital and a well-defined organisational plan

    Gezocht: andere methoden en nieuwe partners: landschapsecologie en WLO

    Get PDF
    De landschapsecologie is inmiddels een gevestigde wetenschap. Toch gaan de biodiversiteit en de kwaliteit van het landschap in Nederland en Vlaanderen nog steeds achteruit. Kunnen we rnet ons vakgebied dan niet meer positieve invloed hebben op landschapsveranderingen? En als we menen van wel hoe dan? Op die vragen gaat dit artikel i

    Aza-Cibalackrot: Turning on Singlet Fission Through Crystal Engineering

    Get PDF
    Singlet fission is a photophysical process that provides a pathway for more efficient harvesting of solar energy in photovoltaic devices. The design of singlet fission candidates is non-trivial and requires careful optimization of two key criteria: (1) correct energetic alignment and (2) appropriate intermolecular coupling. Meanwhile, this optimization must not come at the cost of molecular stability or feasibility for device applications. Cibalackrot is a historic and stable organic dye which, although it has been suggested to have ideal energetics, does not undergo singlet fission due to large interchromophore distances, as suggested by single crystal analysis. Thus, while the energetic alignment is satisfactory, the molecule does not have the desired intermolecular coupling. Herein, we improve this characteristic through molecular engineering with the first synthesis of an aza-cibalackrot and show, using ultrafast transient spectroscopy, that singlet fission is successfully "turned on.
    • …
    corecore