1,001 research outputs found

    Poly(1,3,4-oxadiazoles) via aromatic nucleophilic displacement

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    Poly(1,3,4-oxadiazoles) (POX) are prepared by the aromatic nucleophilic displacement reaction of di(hydroxyphenyl) 1,3,4-oxadiazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The polymerizations are carried out in polar aprotic solvents such as sulfolane or diphenylsulfone using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. The di(hydroxyphenyl) 1,3,4-oxadiazole monomers are synthesized by reacting 4-hydroxybenzoic hydrazide with phenyl 4-hydrobenzoate in the melt and also by reacting aromatic dihydrazides with two moles of phenyl 4-hydroxybenzoate in the melt. This synthetic route has provided high molecular weight POX of new chemical structure, is economically and synthetically more favorable than other routes, and allows for facile chemical structure variation due to the large variety of activated aromatic dihalides which are available

    Using Oblique Imagery to Identify Invasive Plant Species in Onondaga County, NY : a Feasibility Study

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    As the world becomes increasingly connected, the risk of species spreading across previously impermeable boundaries becomes much higher. Many plant and animal species are establishing themselves in entirely new environments, often with significant consequences for indigenous species. This study focused on three non-native plant species-Lythrum salicaria (purple loosestrife), Fallopiajaponica (Japanese knotweed), and Phragmites australis (phragmites or common reed)-- invasives abundant in Onondaga County. This study aimed to test the feasibility of using readily available oblique imagery to identify the presence of these invasive species. Imagery used in the study came from Google Maps Street View photographs of addresses reported to have dense populations of phragmites, Japanese knotweed, or purple loosestrife. Images were uploaded to ERDAS Imagine 2015 and extraction of plant species was tested using both pixel- and object-based classification approaches. Results largely showed these images were not suitable for positive species identification. The oblique images used for testing varied in spatial resolution and time of capture, which may have impacted success of the classifiers. For example, purple loosestrife is more easily separated from its surroundings when blooming; but the available images did not allow us to capitalize on such phenological distinctions. Future research requires a more targeted data set with confirmed species identification, ground validation, and more consistent image quality. Identifying the presence of invasive plant species within imagery is suggested as an important step toward invasive species mitigation efforts

    Development of the BIRD: a metadata modelling approach for the purpose of harmonising supervisory reporting at the European Central Bank - Directorate of general statistics: master and metadata

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    Internship Report presented as the partial requirement for obtaining a Master's degree in Statistics and Information Management, specialization in Information Analysis and ManagementThe work presented is a report documenting the work completed during an Internship at the European Central Bank (ECB), located in Frankfurt Germany from the 15th March 2019 – 15th March 2020. The internship took place in the Directorate of General Statistics (DG-S), specifically in the Master and Metadata section of the Analytical Credit and Master data division (MAM). It will be a continuation of the ECB Internal Banks’ Integrated Reporting Dictionary (BIRD) project as well as management of ECB’s centralised metadata repository, known as the Single Data Dictionary (SDD). The purpose of the dictionary and BIRD Project is to provide the banks with a harmonized data model that describes precisely the data that should be extracted from the banks' internal IT systems to derive reports demanded by supervisory authorities, like the ECB. In this report, I will provide a basis for understanding the work undertaken in the team, focussing of the technical aspect of relational database modelling and metadata repositories and their role in big data analytical processing systems, current reporting requirements and methods used by the central banking institutions, which coincide with the processes set out by the European Banking Authority (EBA). This report will also provide an in-depth look into the structure of the database, as well as the principles followed to create the data model. It will also document the process of how the SDD is maintained and updated to meet changing needs. The report also includes the process undertaken by the BIRD team and supporting members on the banking community to introduce new reporting frameworks into the data model. During this period, the framework for the Financial Reporting (FinRep) standards was included, through a collaborative effort between banking representatives and the master and metadata team

    Plasma Surface Functionalization of AFP Manufactured Composites for Improved Adhesive Bond Performance

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    Application of carbon fiber reinforced polymer (CFRP) as a high-performance structural material has widespread application in the present aerospace industry. However, as-processed composite materials require a comprehensive surface treatment prior to bonding to remove contaminants and impart surface functionality and topography to overcome their poor adhesion properties. Atmospheric pressure plasma jet treatment (APPJT) has been increasingly garnering attention as an alternate method for surface preparation of CFRP. This method has been reported to achieve success in imparting favorable polar functional groups into the composite surfaces enhancing wettability and surface energy of the bonded surfaces. In some cases, APPJT has been demonstrated to remove contaminants or, in the case of silicones, convert them to silica. In this study, an atmospheric pressure plasma jet (APPJ) system was used for surface activation of a composite laid-up by an automated fiber placement (AFP) machine. Surface modifications prior to and after treatment were characterized using water contact angle (WCA) measurements, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Double cantilever beam (DCB) tests were performed to quantify the bonding performance of the composites. The results show a marked enhancement of the mode I interlaminar fracture toughness with the application of APPJT

    Constraints, Compromises and Choice: Comparing Three Qualitative Research Studies

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    Although a number of texts explore social research strategies and methods, most are limited to a basic discussion of such methods and their associated advantages and disadvantages. Few if any, evaluate and compare methods in the context of actual research experiences. This paper endeavours to bridge that gap by reporting the experiences of three researchers working on three separate qualitative studies. All three studies were concerned with investigating the social milieu within organizations. While the research questions were different in each case, all the researchers shared a common goal - to develop explanations for complex social phenomena manifest both internally and externally to each organization. The research strategies, methods and data analyses employed are assessed through the personal evaluations of the researchers. Thus, a singular opportunity is offered for other researchers to benefit from the practical insights and lessons learned. The collective experiences of all three researchers suggest that the contextual conditions and constraints of each study force certain compromises, but which importantly, do not compromise qualitative research studies

    The language of leadership in Laos

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    © 2016, © The Author(s) 2016. This paper responds to recent calls in the leadership studies literature for anthropologically informed empirical research on leadership phenomena in non-Western and non-Anglophone settings. The authors have worked extensively on rural development projects in Laos and draw on ethnographic ‘observant-participation’ and interview data to explore how leadership is construed in a contested terrain where traditional concepts intersect with those of official government and international development agencies. A theoretical discussion of linguistic relativity and the socially constitutive nature of language in general is offered as background justification for studying the language of leadership in context. The anthropological distinction between etic and emic operations is also introduced to differentiate between various interpretative positions that can be taken in relation to the fieldwork and data discussed in this paper. The study shows how difficult it can be for native Lao speakers to find words to describe leadership or give designations to ‘leaders’ outside of officially sanctioned semantic and social fields. A key finding of the study is that, viewed from the perspective of the Lao People’s Revolutionary Party, authority and leadership are coextensive. This social fact is reflected in the linguistic restrictions on what can and cannot be described as leadership in Laos

    Forages and farmers: case studies from South-East Asia

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    Microbial communities in dark oligotrophic volcanic ice cave ecosystems of Mt. Erebus, Antarctica.

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    The Earth's crust hosts a subsurface, dark, and oligotrophic biosphere that is poorly understood in terms of the energy supporting its biomass production and impact on food webs at the Earth's surface. Dark oligotrophic volcanic ecosystems (DOVEs) are good environments for investigations of life in the absence of sunlight as they are poor in organics, rich in chemical reactants and well known for chemical exchange with Earth's surface systems. Ice caves near the summit of Mt. Erebus (Antarctica) offer DOVEs in a polar alpine environment that is starved in organics and with oxygenated hydrothermal circulation in highly reducing host rock. We surveyed the microbial communities using PCR, cloning, sequencing and analysis of the small subunit (16S) ribosomal and Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (RubisCO) genes in sediment samples from three different caves, two that are completely dark and one that receives snow-filtered sunlight seasonally. The microbial communities in all three caves are composed primarily of Bacteria and fungi; Archaea were not detected. The bacterial communities from these ice caves display low phylogenetic diversity, but with a remarkable diversity of RubisCO genes including new deeply branching Form I clades, implicating the Calvin-Benson-Bassham (CBB) cycle as a pathway of CO2 fixation. The microbial communities in one of the dark caves, Warren Cave, which has a remarkably low phylogenetic diversity, were analyzed in more detail to gain a possible perspective on the energetic basis of the microbial ecosystem in the cave. Atmospheric carbon (CO2 and CO), including from volcanic emissions, likely supplies carbon and/or some of the energy requirements of chemoautotrophic microbial communities in Warren Cave and probably other Mt. Erebus ice caves. Our work casts a first glimpse at Mt. Erebus ice caves as natural laboratories for exploring carbon, energy and nutrient sources in the subsurface biosphere and the nutritional limits on life
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