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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.
101

Concentration Effect of Organic Phosphors Pumped by Blue LED

Chen, Hsin-Nan 25 July 2008 (has links)
In this thesis , we used organic phosphors 10-(2-benzothiazolyl) -1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11Hbenzo[l]-pyrano[6,7,8-ij]inolizin-11- one (C545T) and 10-(2-benzothiazolyl)- 1,3,3,7,7-pentametquhyl-2, 3, 6,7-tetrahydro-1H,5H,11H-benzo[l]-pyrano[6,7,8-ij]-quinolizin-11-one(C-545P) , by mixed method to package for LED. First , we used C545T and C545P with different concentration of Silicone ,to find the best mixed ratios. Organic C545T and C545P were proposed to be the candidate of the green phosphor. The emitting peaks of C545P and C545T were 496 nm and 500 nm measured by photoluminescence, respectively. Organic green phosphors were mixed with silicone with different concentration.The optimal mixed weight ratio of phosphor to silicone were 1:500 and 1:300 for C545P and C545T,respectively. Second, we used InGaN/GaN multi-quantum well(MQW) Blue chip toexcite Organic phosphors were mixed with silicone with different concentration to fabricated device. With an injected current 20 mA ,we obtained the luminous efficiency was 79 lm/W , CIE coordinate at (0.33, 0.60) of packaged device C545T @ 1:500 ,and then the luminous efficiency was 68 lm/W , CIE coordinate at (0.33, 0.60) of package device C545P @1:300.Compared with commercial InGaN green LED , we find mixed organic phosphors packaged devices of luminous flux and luminous efficiency and have improved. The best mixed at 1:500 packaged device of C545T and silicone, and luminous efficiency increase 1/3.
102

Mise en oeuvre de la politique de la concurrence dans le cadre du contrôle des concentrations horizontales

Dargaud, Emilie. Flochel, Laurent January 2007 (has links)
Reproduction de : Thèse de doctorat : Sciences économiques : Lyon 2 : 2007. / Titre provenant de l'écran-titre. Bibliogr.
103

Examining industry concentration in the plant biotechnology sector /

Williams, Heather Renee, January 2010 (has links) (PDF)
Thesis (M.A.)--Eastern Illinois University, 2010. / Includes bibliographical references (leaves 61-65).
104

Temporal and spatial analysis of suspended sediment distribution in the Amazon River using satellite imagery

Park, Edward 30 October 2013 (has links)
Patterns of surface sediment concentration distribution in rivers are significant for understanding the broad ranges of fluvial environmental systems. In the case of the Amazon Basin, the complexity in the sediment pattern distribution is affected by the anabranching channel pattern of the Amazon River, the input by tributaries (some of which are among the largest rivers on earth) and the existence of huge and complex floodplains. Until recently, the assessment of sediment fluxes has been concentrated on hydro-sedimentological techniques in the Amazon Basin; however, efforts on characterizing the patterns of sediment transport have been neglected. This study aims to improve the understanding of the pattern of sediment distributions over a large scale in the Amazon River by estimating surface sediment concentration with remote sensing techniques. Field acquired surface sediment concentration values were supplied from three gauging stations representing the upstream, midstream and downstream sections of the Amazon River from 2000 to 2010 and calibrated with MODIS surface reflectance products (N=207, 232, 313, respectively). Empirical models were derived with robust causalities (0.63<R2<0.92) between field surface sediment concentration and surface reflectance from each station; however, sensitivity of reflectance around each stations were shown to be significantly affected by the local hydrological behaviors, leaving implications on analysis of the geomorphic characteristics affecting these associations. Overall, the capability of the remote sensing-based platform introduced in this study is successfully demonstrated by capturing the spatial and temporal variability of surface sediments in the Amazon River Basin, which is the largest and the most complex river system on earth. / text
105

The influence of hydrogen ion concentration on the reaction of diazonium salts in ethanol

Zolton, Lorraine, 1935- January 1960 (has links)
No description available.
106

Emotion, concentration and performance in a Swedish female handball team : Development and implementation of the team specific instrument

Olausson, David, Vallmark Jansson, Jasper January 2014 (has links)
The present study is a mixed method longitudinal design, containing three objectives. Object one was to develop a team-specific survey instrumentin order to measure emotion, concentration and performance during a game. Object two was to examine the dynamics of emotion, concentration and performance in successful and less successful games. Object three was to study the relationship between emotion, concentration and performance in successful and less successful games. The participants (n= 15, age= 22.8) in the study consisted of 15 women, all players in the same elite handball team.Qualitative data was obtained by two workshops in order to construct the instrument. Quantitative data was collected after games, using the team specific instrument. The study includes data over a six game period containing four successful games and two less successful games. Results showed a significant difference between successful and less successful games regarding all three variables measured. Both positive and negative relationships were found. The results also showed different relationships regarding successful and less successful games. Several practical team-specific applications were suggested, such as working with emotional regulation to enhance performance. Investigating if athletes are more prone to be influenced emotionally by their performance when performing poorlyis one of several suggestions proposed for future directions.
107

Hydrogen ion relationships in soils /

Raupach, Maxwell. January 1953 (has links) (PDF)
Thesis (M.Sc.)--University of Adelaide, 1953. / Typewritten copy.
108

Three essays on ownership concentration in New Zealand : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Accounting at Lincoln University /

Jiang, Haiyan, January 2009 (has links)
Thesis (Ph. D.) -- Lincoln University, 2009. / Also available via the World Wide Web.
109

Hydrogen-ion concentration studies of Minnesota soils ...

Fieger, E. A. January 1900 (has links)
Thesis (Ph. D.)--University of Minnesota, 1924. / Biographical sketch. Bibliography: l. 50-54.
110

Neue Bremm - Terrorstätte der Gestapo : ein erweitertes Polizeigefängnis und seine Täter 1943-1944 /

Thalhofer, Elisabeth. January 2002 (has links)
Diss.--Saarbrücken, 2001. / Bibliogr. p. 267-285.

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