985 resultados para William P. Whelihan III


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This paper reports the thermomechanical sensitivity of bimaterial cantilevers over a mid-infrared (IR) spectral range (5-10 µm) that is critical both for chemical analysis via vibrational spectroscopy and for direct thermal detection in the 300-700 K range. Mechanical bending sensitivity and noise were measured and modeled for six commercially available microcantilevers, which consist of either an aluminum film on a silicon cantilever or a gold film on a silicon nitride cantilever. The spectral sensitivity of each cantilever was determined by recording cantilever deflection when illuminated with IR light from a monochromator. Rigorous modeling and systematic characterization of the optical system allowed for a quantitative estimate of IR energy incident upon the cantilever. Separately, spectral absorptance of the cantilever was measured using Fourier transform infrared (FT-IR) microscopy, which was compared with analytical models of radiation onto the cantilever and heat flow within the cantilever. The predictions of microcantilever thermomechanical bending sensitivity and noise agree well with measurements, resulting in a ranking of these cantilevers for their potential use in IR measurements.

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The engineering of liquid behavior on surfaces is important for infrastructure, transportation, manufacturing, and sensing. Surfaces can be rendered superhydrophobic by microstructuring, and superhydrophobic devices could lead to practical corrosion inhibition, self-cleaning, fluid flow control, and surface drag reduction. To more fully understand how liquid interacts with microstructured surfaces, this dissertation introduces a direct method for determining droplet solid-liquid-vapor interfacial geometry on microstructured surfaces. The technique performs metrology on molten metal droplets deposited onto microstructured surfaces and then frozen. Unlike other techniques, this visualization technique can be used on large areas of curved and opaque microstructured surfaces to determine contact line. This dissertation also presents measurements and models for how curvature and flexing of microstructured polymers affects hydrophobicity. Increasing curvature of microstructured surfaces leads to decreased slide angle for liquid droplets suspended on the surface asperities. For a surface with regularly spaced asperities, as curvature becomes more positive, droplets suspended on the tops of asperities are suspended on fewer asperities. Curvature affects superhydrophobicity because microscopic curvature changes solid-liquid interaction, pitch is altered, and curvature changes the shape of the three phase contact line. This dissertation presents a model of droplet interactions with curved microstructured surfaces that can be used to design microstructure geometries that maintain the suspension of a droplet when curved surfaces are covered with microstructured polymers. Controlling droplet dynamics could improve microfluidic devices and the shedding of liquids from expensive equipment, preventing corrosion and detrimental performance. This dissertation demonstrates redirection of dynamic droplet spray with anisotropic microstructures. Superhydrophobic microstructured surfaces can be economically fabricated using metal embossing masters, so this dissertation describes casting-based microfabrication of metal microstructures and nanostructures. Low melting temperature metal was cast into flexible silicone molds which were themselves cast from microfabricated silicon templates. The flexibility of the silicone mold permits casting of curved surfaces, which this dissertation demonstrates by fabricating a cylindrical metal roller with microstructures. The metal microstructures can be in turn used as a reusable molding tool. This dissertation also describes an industrial investment casting process to produce aluminum molds having integrated microstructures. Unlike conventional micromolding tools, the aluminum mold was large and had complex curved surfaces. The aluminum was cast into curved microstructured ceramic molds which were themselves cast from curved microstructured rubber. Many structures were successfully cast into the aluminum with excellent replication fidelity, including circular, square, and triangular holes. This dissertation demonstrates molding of large, curved surfaces having surface microstructures using the aluminum mold. This work contributes a more full understanding of the phenomenon of superhydrophobicity and techniques for the economic fabrication of superhydrophobic microstructures.

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Improvements to the current state of the art in microfabricated cantilevers are investigated in order to realize enhanced functionality and increased versatility for use in ultrafast electrophoretic molecular sorting and delivery. Design rationale and fabrication process flow are described for six types of electro-thermal microcantilevers. Devices have been tailored for the process of separating mixtures of heterogeneous molecules into discrete detectable bands based on electrophoretic mobility, and delivering them to a conductive substrate using electric fields. Four device types include integrated heating elements capable of warming samples to catalyze reactions or cleaning the device for reuse. Similar devices have been shown to be capable of targeting temperatures between ambient conditions and the melting point of silicon, to within 0.1˚C precision or better. All microcantilevers types are equipped with a highly doped conductive silicon tip capable of interacting with a conductive substrate to deliver molecules under the presence of an electric field. Devices are equipped with additional electrodes to aid in sorting molecules on the surface of the probe end. Two designs contain two legs and one additional sorting electrode while four designs contain three legs and have two sorting electrodes. Devices having two sorting electrodes are designed to be capable of sorting three or more molecular species, a distinctive advancement in the state of the art. A detailed process flow of the fabrication process for all six electro-thermal cantilever designs are explained in detail.

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The purpose of this thesis is to consider the factors that impact decision making in city park settings, with specific emphasis given to wildlife. Additionally, professional bias was considered as a possible response determinant. Studies connecting perceptions of wildlife and Illinois park managers have been rare or nonexistent, but offer the potential for the improvement of management strategies and recreational opportunities. Data was collected using mixed methods. City recreation practitioners statewide were invited to complete a self-administered questionnaire considering wildlife as a decision-making factor in land acquisition or restoration decisions. A small follow-up sample of park managers was interviewed via telephone for further explanation of their response. Analysis of responses from questionnaires and interviews suggested that wildlife habitat is a factor in land use decision making, but is not considered one of the highest importance. Respondents identified that nuisance wildlife, access to wildlife, and public value of wildlife were also factors in decision making. Factors associated with a high-ranking of the importance of wildlife were agencies with a high number of natural area acres, a high number of overall park acreage, personnel devoted to natural area management, the presence of hiking trails, and cities with a large population. Professional bias of recreation managers was suggested via anecdotal interview data, but could not be empirically connected with wildlife-related decision-making processes, as no managers identified themselves as having completed formal wildlife-related training. As a result, management implications include separate training for both practitioners and public. This study broadens the understanding of wildlife management in city park settings, and reaffirms that further understanding of public and pracitioner values of wildlife will lead to improved land use decisions and recreationally valuable experiences.

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Abstract available: p. [ii]-[iii].

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Briefwechsel zwischen Bertold Scheller und Max Horkheimer, 1955; Briefwechsel zwischen dem Diplom-Volkswirt Albert Schiefer und Max Horkheimer, 1957; Briefwechsel zwischen dem Bayerischer Schulbuch-Verlag und Max Horkheimer, 1954; Briefwechsel mit Beilagen zwischen der Deutschen Schlafwagen- und Speisewagen-Gesellschaft und Max Horkheimer, 1954; 1 Brief von Ludwig Benedict Schlesinger an Max Horkheimer, 1958; 1 Brief von dem Professor Alfred Schmidt an Max Horkheimer, 1957 und 1 Gutachten von Max Horkheimer, 1958; 1 Brief von Hermann Schweppenhäuser an Max Horkheimer, 1957; Briefwechsel zwischen W. Schmidt-Richberg und Max Horkheimer, 1957-1958; Briefwechsel zwischen Alfred Schmidweber und Max Horkheimer, 1956; 1 Brief von Katja Schmitz? an Max Horkheimer, 1955; Briefwechsel zwischen der Studentin Elsmarie Schmitz und Max Horkheimer, 1958; Briefwechsel zwischen dem Professor Günter Schmölders und Max Horkheimer, 1957-1958; 1 Brief an Diplom-Volkswirt Helmut Schneider von Max Horkheimer, 1955; Briefwechsel zwischen Marianne Schneider und Max Horkheimer, 1955-1956; Briefwechsel zwischen Georg von Schnitzler und Max Horkheimer, 1954; 1 Todenanzeige von Louis Schnürpel, 1956; Briefwechsel zwischen Roman Schnur und Max Horkheimer, 1955-1958; 1 Brief mit Anlagen an Günter P. Schölzel von Max Horkheimer, 1958; Briefwechsel zwischen Hans W. Schoenberg und Max Horkheimer, 1955; 1 Anzeige von Arnold Schoenberg, 1955; Briefwechsel zwischen der Studentin Annemarie Schöne und Max Horkheimer, 1956; Briefwechsel zwischen dem Professor Hans Joachim Schoeps und Max Horkheimer, 1955-1956; 1 Brief an den Professor Rudolf Schottlaender von Max Horkheimer, 1955; 1 Anzeige von Joachim Schroeter, 1955; Briefwechsel zwischen Karl Schück und Max Horkheimer, 1954; Briefwechsel zwischen Julia von der Schulenburg und Max Horkheimer, 1957; Briefwechsel zwischen dem Bankdirektor Felix W. Schulthess und Max Horkheimer, 1955; 1 Brief an den Privatdozent Walter Schulz von Max Horkheimer, 1954; Briefwechsel mit Beilagen zwischen dem Bürgermeister Wolfgang Schwabe und Max Horkheimer, 1954; Breifwechsel mit Beilagen zwischen Hans Schwalbach und Max Horkheimer, 1954; Briefwechsel mit Beilagen zwischen Poldi Schwalbach und Max Horkheimer, 1954; 1 Brief von Louis Daniel Schwallbach an Max Horkheimer, 1955; Briefwechsel zwischen Dorothea de Schweinitz und Max Horkheimer, 1958; 1 Aktennotiz von Hans Zulliger, 1956; Briefwechsel zwischen William Schwitzer und Max Horkheimer, 1954; Briefwechsel zwischen Karl von Stackelberg und Max Horkheimer, 1954; 1 Brief von Clemens Köttelwesch und Max Horkheimer, 1957; 1 Brief von dem Oberlandesgerichtspräsidenten Bruno Heusinger an Max Horkheimer, 1954; Briefwechsel zwischen dem Oberstadtdirektor Erich Walter Lotz und Max Horkheimer, 1953-1954; Briefwechsel zwischen der Stadtverwaltung Iserlohn und Max Horkheimer, 1954; Briefwechsel mit Beilagen zwischen dem Diplom Ingenieur und Oberbaurat Julius Schwalm und Max Horkheimer, 1954; 1 Brief an den Professor Herbert Plügge von Max Horkheimer, 1957; Briefwechsel zwischen den Professor und Oberlandesgerichtspräsidenten Curt Staffund Max Horkheimer, 1956-1957; 1 Brief von dem Professor B. M. Stanfield an Max Horkheimer, 1957; 1 Vermählungsanzeige von den Professor Dietrich Starck, 1956 und 1 Brief an den Professor Dietrich Starck von Max Horkheimer, 1958; Briefwechsel zwischen den Professor Werner Stark und Max Horkheimer, 1958; Briefwechsel mit Beilagen zwischen Rolf Stätter und Max Horkheimer, 1954; 1 Brief von Karl Staufen an Max Horkheimer, 1952; 1 Brief von Direktor Adolf Stauss an Max Horkheimer, 1954; Briefwechsel zwischen dem Bankier Alwin Steffan und Max Horkheimer, 1954-1957; 2 Briefe an den Professor Wolfgang Stegmüller von Max Horkheimer, 1957; Briefwechsel zwischen dem Professor und MinisterErwin Stein und Max Horkheimer, 1956-1957; 1 Brief an Lotte Steinberger von Max Horkheimer, 1954; 1 Brief von Ernst Steindorf an Max Horkheimer, ohne Jahr; Briefwechsel zwischen Helmut von den Steinen und Max Horkheimer, 1955 und 1 Brief an Helmut von den Steinen von Theodor W. Adorno, 1955; Briefwechsel zwischen den Professor Hans Erich Stier, 1958; Briefwechsel zwischen Elsbeth Stocker und Max Horkheimer, 1955; Briefwechsel zwischen Eric W. Stoetzner und Max Horkheimer, 1957-1958; Briefwechsel zwischen Gertrud Straulino und Max Horkheimer, 1957-1958; Briefwechsel zwischen den Professor Siegfried Strugger und Max Horkheimer, 1955; Briefwechsel mit Beilagen zwischen Willy Strzelewicz und Max Horkheimer, 1955-1957; Briefwechsel mit Beilagen zwischen der Studentenschaft der Universität Köln und Max Horkheimer, 1953;

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Copy of a one-page letter concerning the payment of a bill.

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Draft of a one-page letter concerning the payment of a bill and mentioning Croswell's health.

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'Now first published from the originals.'--t.p.

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Bibliography: p. [249]-254.

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Asymmetric tri-bridged diruthenium(III) complexes, [Ru2O(O(2)CR)(3)(en) (PPh(3))(2)](ClO4) (R = C6H4-p-X: X = OMe (1a), Me (1b); en=1,2-diaminoethane), were prepared and structurally characterized. Complex 1a 3CHCl(3), crystallizes in the triclinic space group P (1) over bar with a = 14.029(5), b = 14.205(5), c = 20.610(6) Angstrom, alpha= 107.26(3), beta = 101.84(3), gamma= 97.57(3)degrees, V= 3756(2) Angstrom(3) and Z = 2. The complex has an {Ru-2(mu-O)(mu-O(2)CR)(2)(2+)} core and exhibits [O4PRu(mu-O)RuPO2N2](+) coordination environments for the metal centers. The novel structural feature is the asymmetric arrangement of ligands at the terminal sites of the core which shows an Ru... Ru separation of 3.226(3) Angstrom and an Ru-O-Ru angle of 119.2(5)degrees. An intense visible band observed near 570 nm is assigned to a charge transfer transition involving the d pi-Ru(III) and p pi-mu-O Orbitals. Cyclic voltammetry of the complexes displays a reversible Ru-2(III,III) reversible arrow Ru-2(III,IV) couple near 0.8 V (versus SCE) in MeCN-0.1 M TBAP.

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Diruthenium (II. III) complexes of the type [Ru-2(O2CAr)(4) (2-mimH)(2)](ClO4) (Ar = C6H4-p-X : X=OMe,1, X=Me, 2, 2-mimH=2-methylimidazole) have been isolated from the reaction of Ru2Cl(O2CAr)(4) with 2-mimH in CH2Cl2 followed by the addition of NaClO4. The crystal structure of 1.1.75CH(2)Cl(2).H2O has been determined. The crystal belongs to the monoclinic space group p2(1)/c with the following unit cell dimensions for the C40H40N4O16ClRu2.1.75CH(2)Cl(2).H2O (M = 1237.0) : a = 12.347(3)Angstrom, b = 17.615(5)Angstrom, c = 26.148(2)Angstrom,beta = 92.88(1)degrees. v = 5679(2)Angstrom(3). Z=4, D-c = 1.45 g cm(-3). lambda(Mo-K-alpha) = 0.7107 Angstrom, mu(Mo-K-alpha) = 8.1 cm(-1), T = 293 K, R = 0.0815 (wR(2) = 0.2118) for 5834 reflections with 1 > 2 sigma(I). The complex has a tetracarboxylatodiruthenium (II, III) core and two axially bound 2-methylimidazole ligands. The Ru-Ru bond length is 2.290(1)Angstrom. The Ru-Ru bond order is 2.5 and the complex is three-electron paramagnetic. The complex shows an irreversible Ru-2(II,III)-->Ru-2(Il,II) reduction near -0.2 V vs SCE in CH2Cl2-0. 1 MTBAP. The complexes exemplify the first adduct of the tetracarboxylatodiruthenium (II,III) core having N-donor ligands