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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fabrication, characterization and optical properties of three-dimensional colloidal gold nanostructures

Addison, Christopher James 10 April 2008 (has links)
3-Dimensional nanostructures were constructed through the alternate immersion of a derivatized glass slide in solutions of propanedithiol and gold nanoparticles. The size and shape of the surface features could be controlled based on the number of nanoparticle depositions. Characterization of the substrates was performed using W-Vis spectroscopy and atomic force microscopy. The multilayer nanoparticle substrates were examined for their suitability in surface-enhanced Raman scattering (SERS) by obtaining the SERS spectrum of oxazine-720 on the substrates. A dramatic increase in the SERS signal is noted with increasing nanoparticle layers and reaches a maximum for 11 nanoparticle-layer depositions. The enhancement is attributed to the underlying surface morphology: Surface features on the order of 40 nm in size yield the greatest SERS enhancement due to surface plasmon (SP) excitation. The non-linear optical properties of colloidal nanostructures were examined using second harmonic generation (SHG). A pronounced second harmonic emission was noted for 13 nanoparticle layers and was attributed to SP excitation to yield surface-enhanced SHG. The self-assembly of gold nanorods to form 3-dimensional nanostructures was examined. While the self-assembly was not successful, the aggregated gold nanorods exhibited a large SERS enhancement. This suggests that the incorporation of gold nanorods into SERS substrates is a viable avenue for future research.
2

Nanostructuration de réseaux époxydes par des copolymères à blocs de type ABC

Ritzenthaler, Sophie. Pascault, Jean-Pierre Girard-Reydet, Emmanuel. January 2002 (has links)
Thèse de docteur-ingénieur : Matériaux macromoléculaires et composites : Villeurbanne, INSA : 2000. / Thèse : 2000ISAL0094. Titre provenant de l'écran-titre. Bibliogr. p.163-173.
3

Synthesis and field emission studies of 1-D nanostructures

Kulkarni, Niraj Narasinha 28 August 2008 (has links)
Not available / text
4

Novel synthesis techniques for nanostructures

Jalilian, Romaneh, January 2004 (has links) (PDF)
Thesis (M.S.)--University of Louisville, 2004. / Department of Physics. Vita. "December 2004." Includes bibliographical references (leaves 64-[65] ).
5

Synthesis and field emission studies of 1-D nanostructures

Kulkarni, Niraj Narasinha, Shih, Chih-Kang, Yao, Zhen, January 2005 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisors: Chih-Kang Shih and Zhen Yao. Vita. Includes bibliographical references.
6

Design and fabrication of nano/micro structures with an integrated nanomanipulation system. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Due to the advances in nanotechnology and its growing of potential applications, it is evident that the development of practical technologies for the manipulation of nanostructures is essential. The focus of this dissertation is to develop an integrated nanomanipulation system that would be able to image, manipulate as well as fabricate micro/nano-scaled structures in a controlled manner. The system consists of four main components: an Atomic Force Microscope (AFM) for obtaining topographic information of sample surfaces, a haptic device controlled by a server which generates the force environment, a molecular dynamics simulation for determinations of the effects of force application on nano particles, and a visualization program for display of the results. An extended platform with high precision and accuracy is included for broadening the workspace. The interface would be implemented for direct interaction with nano molecules. The users are then allowed to see, touch and manipulate such particles. By the principle of contact mechanics, the tip-sample interaction forces and intermolecular forces between the tip and surface can be modeled; calculated forces are used to predict the results of each operation. The proposed nanomanipulation model facilitates further improvement to accommodate other physical phenomena that characterize the mechanics of nanomanipulation. / Nanotechnology has been defined as a description of activities at the atomic level that have applications in the real world. Advances in the field of nanotechnology have expanded the breadth of potential applications tremendously in recent years, which also leads to rapid growth of several research and development areas throughout the world. Recent development in microelectronics, nano-optics and generic chips shows the trend driving towards miniaturization. Gaining access to the nano world also enable us to make further advances in obtaining precise measurement of material properties and exploring fundamental physical laws at the atomic level. / The aim for developing such an integrated system is for prototyping of optics components with micro/nano structures, especially for diffractive optics elements (DOE) and optical lightguide. Diffractive optics is a transmissive diffraction grating with a series of closely ruled lines on a piece of transmissive substrate, A collimated beam of monochromatic light incident on a grating will result in the defined light diffraction pattern. The lightguide is being commonly adopted in backlight system, the spatially varying extraction pattern will couple flux out of the light guide to produce a spatially uniform luminance distribution. Determining the ruled lines for diffraction grating and extraction pattern for lightguide is greatly facilitated through the use of optimization. With the imposition of nonlinear constraints, optimization is achieved by incorporating the approximating function into an optimization algorithm. The micro/nano patterns on DOE and optical lightguide are feasible to be fabricated by the integrated nanomanipulation system with the AFM probe tip as a cutting tool. The characteristics of the AFM probe tip are also taken into account when designing the optical elements. / The developed system has been validated by different experiments, including raster scanning, nanoindentation and nanomanipulation testing. New application of nanomanipulation in photonics has been explored. With the proposed nanostructure fabrication techniques, several optical components can be fabricated in a more efficient and cost-effective way. / Fok, Lo Ming. / Adviser: Yun Hui Lin. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0611. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 121-123). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.
7

Organic optoelectronic materials optical properties and 1D nanostructure fabrication /

Tong, Wing-yun. January 2006 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
8

Forced Convection in Microchannels with Nanostructures on One Wall

Jakaboski, Blake Elaine 14 May 2004 (has links)
New electronic devices are faster than ever before, incorporate a higher level of integration, and as a result, need to dissipate higher heat fluxes. Active cooling is the only possible method of thermal management for these devices. A new type of microchannel heat sink has been developed and evaluated in this study. The device consists of silicon microchannels on whose bottom surfaces multi-walled carbon nanotubes are grown. The objective of the study is to investigate the effect of carbon nanotubes on the heat transfer characteristics. The heat sink size is 15 mm by 15 mm by 0.675 mm. It contains two microchannel designs. One consists of eight channels of cross section 682 micrometers by 50 micrometers; the other has six channels of cross section 942 micrometers by 50 micrometers. The heat sink is incorporated in an open loop flow facility, with water as the coolant. Six different configurations are compared. Two have no nanotubes, two have closely spaced nanotubes, while the last two designs have widely spaced nanotubes. The tests utilize an infrared camera as well as thermocouples placed in the flow for characterization. The heat transfer characteristics are compared for the different cases.
9

Optical properties of charged excitons in semiconductor nanostructures /

Esser, Axel, January 2002 (has links)
Extr. de: Diss.--Physique--Berlin--Humboldt universitat, 2001. / Bibliogr. p. 100-107.
10

Synthetic approaches to one-dimensional nanostructures /

Mayers, Brian T. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 182-201).

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