1,721,261 research outputs found
Webb, William N.
No full textMilitary Information: Seaman, Fourth Battalion, Naval Militia, U.S. Naval AirStation, Bayshore Long Island.This project was assisted by a grant from the New Jersey Historical Commission, a division of the Department of State
Design of heterogeneous catalysts for the utilisation of carbon dioxide and tandem reactions
No full textThe adoption of green technologies and principles by the chemical industry, and chemistry as a whole, is urgently required to help mitigate and ultimately reverse the alarming trends in global greenhouse gas emissions. Green processes such as carbon dioxide utilisation enable the incorporation of a waste material in the production of valuable synthetic chemicals. The catalysed reaction of CO2 with epoxides is a particularly attractive example as the cyclic carbonate product has wide-ranging commercial applications. Recyclable, heterogeneous catalysts are at the forefront of research efforts to produce cyclic carbonates in a sustainable manner.Through the development of an imidazole based organocatalyst covalently bound via pendant silanols to mesoporous silica, the efficacy and principles of heterogenised imidazoliums as catalysts for cyclic carbonates production was established. A facile anchoring strategy allowed for manipulation of the active site, which, with detailed physico-chemical and spectroscopic characterisation, established the catalytic mechanism, allowed for progressive optimisation and improved catalytic application.The robustness of the anchoring method and the excellent activity of the functionalised imidazole catalysts led to their incorporation into supports of greater complexity. By employing analogous immobilisation methods, an imidazolium species was anchored to hierarchically porous aluminophosphates and silicoaluminophosphates where careful tuning of the framework properties improved the reaction selectivity towards the cyclic carbonate product.Further heterogenisation of functionalised imidazoles onto the coordinatively unsaturated sites within the metal organic framework (MOF), MIL-101(Cr), resulted in a hybrid MOF with exceptional activity for the reaction of CO2 and epoxides, under halide-free and solvent-free conditions. Comprehensive characterisation, in combination with molecular modelling simulations, allowed for structure-property relationships to be established, enabling optimisation to afford high cyclic carbonate yields whilst employing short reaction times, relatively benign conditions and low catalyst loadings.To further illustrate the scope of hybrid MOFs for sustainable applications the robust MOF, UiO-66(Zr), was exploited in a tandem catalytic reaction. Colloidal deposition of gold nanoparticles onto UiO-66-NH2 framework enabled successive alcohol oxidation-Knoevenagel condensation reactions to be achieved at good yields, for a range of substrates. Furthermore the extension of the capabilities of the aforementioned MIL-101(Cr) framework to a different, epoxidation-CO2 utilisation cascade reaction demonstrated the vast scope of applications achievable with hybrid MOFs for green and sustainable catalytic processes
QAM techniques for digital mobile radio
No full textSIGLEAvailable from British Library Document Supply Centre- DSC:DX180754 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Evolved spectrum usage rights: A catalyst for liberal spectrum management reform
No full textRadio spectrum is critically important to the functioning of modern society but is a scarce resource in great demand. Ideally, it should be allocated to the most valuable uses in a country and used as intensively as possible. Yet, we are far from this, with spectrum use entrenched for decades and much of spectrum unused for much of the time. Changing usage is typically bureaucratic and glacially slow compared to the speed of innovation. That is, the promise of spectrum management reforms has not been delivered so far. We promulgate and endorse the earlier views that the key elements needed to progress with spectrum liberalisation are fully flexible spectrum property rights where the use can be changed by the licence holder subject to interference constraints, improved conditions for secondary trading to enable change of ownership, and the lightest touch regulatory intervention. We propose and explain a comprehensive policy framework based on the concept of Evolved Spectrum Usage Rights (eSUR) that enables change of use and innovation that can apply to all exclusive spectrum licensing. We elaborate on this to discuss a practical path and roadmap to the future to realise a world where spectrum can deliver much greater value than currently. The proposed policy measures apply predominantly to commercial spectrum, but some elements might also help with public sector spectrum
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Maintaining soil fertility
No full textCitation: Webb, William Allen. Maintaining soil fertility. Senior thesis, Kansas State Agricultural College, 1904.Morse Department of Special CollectionsIntroduction: Having lived for a number of years upon a southern Kansas wheat farm and observed the steady decrease in the productive power of the land, the writer has been interested in investigating practical methods by which this loss might be prevented and the soil maintained in a high state of productivity. For years, many farms in the Kansas wheat belt have been sown continuously in wheat. This means that every year with a crop of twenty bushels, there have been removed from each acre of such farms, thirty-five pounds of nitrogen twenty pounds of phosphoric acid and thirty-five pounds of potash.Only in rare cases have any fertilizing materials..
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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