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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.
11

Stabilisation of high-yield pulp against photo-induced discolouration

Quiddington, Christopher John January 2001 (has links)
No description available.
12

Template-assisted synthesis of biomorphic MoO₃ compound and its catalytic effect on the degradation of methyl violet. / 模板辅助下制备有生物形态的MoO₃化合物以及它对降解甲基紫的催化作用 / Template-assisted synthesis of biomorphic MoO₃ compound and its catalytic effect on the degradation of methyl violet. / Mo ban fu zhu xia zhi bei you sheng wu xing tai de MoO₃ hua he wu yi ji ta dui jiang jie jia ji zi de cui hua zuo yong

January 2010 (has links)
by Diao, Zhenyu = 模板辅助下制备有生物形态的MoO₃化合物以及它对降解甲基紫的催化作用 / 刁振玉. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references. / Abstracts in English and Chinese. / by Diao, Zhenyu = Mo ban fu zhu xia zhi bei you sheng wu xing tai de MoO₃ hua he wu yi ji ta dui jiang jie jia ji zi de cui hua zuo yong / Diao Zhenyu. / Abstract --- p.I / 摘要 --- p.II / Acknowledgement --- p.III / Table of contents --- p.IV / List of figures --- p.VII / List of tables --- p.X / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Biomorphic materials --- p.1 / Chapter 1.2 --- Semiconductor catalysts --- p.2 / Chapter 1.3 --- Methyl violet --- p.3 / Chapter 1.4 --- Photocatalysis --- p.4 / Chapter 1.5 --- Synthesis of biomorphic catalysts --- p.8 / Chapter 1.6 --- Objectives and thesis layout --- p.10 / References / Chapter Chapter 2 --- Methodology and Instrumentation --- p.17 / Chapter 2.1 --- Sample preparation --- p.17 / Chapter 2.1.1 --- Synthesis --- p.17 / Chapter 2.1.2 --- Paper templates and precursors --- p.18 / Chapter 2.2 --- Characterization --- p.18 / Chapter 2.2.1 --- Scanning electron microscope (SEM) --- p.18 / Chapter 2.2.2 --- X-ray powder diffractometry (XRD) --- p.20 / Chapter 2.2.3 --- Fourier transform infrared (FTIR) spectroscopy --- p.21 / Chapter 2.2.4 --- Differential thermal analysis (DTA) --- p.23 / Chapter 2.2.5 --- Thermogravimetric analysis (TGA) --- p.24 / Chapter 2.2.6 --- Ultraviolet-Visible spectroscopy (UV-Vis) --- p.24 / Chapter 2.3 --- Catalytic performance --- p.26 / References --- p.26 / Chapter Chapter 3 --- Results Introduction --- p.30 / Chapter 3.1 --- Paper template --- p.31 / Chapter 3.1.1 --- Thermal properties --- p.31 / Chapter 3.1.2 --- Composition of paper template --- p.32 / Chapter 3.1.3 --- Morphology of paper --- p.35 / Chapter 3.2 --- Chemical precursors --- p.40 / Chapter 3.3 --- Infiltrated paper templates --- p.43 / Chapter 3.4 --- Biomorphic products --- p.46 / Chapter 3.4.1. --- Influence of annealing temperature --- p.46 / Chapter 3.4.1.1 --- Phase and composition --- p.46 / Chapter 3.4.1.2. --- Surface morphology --- p.48 / Chapter 3.4.2 --- Effects of annealing durations --- p.50 / Chapter 3.4.2.1 --- Phase and composition --- p.50 / Chapter 3.4.2.2 --- Surface morphology --- p.54 / Chapter 3.5 --- Formation mechanism --- p.56 / References --- p.57 / Chapter Chapter 4 --- Catalytic performance Introduction --- p.59 / Chapter 4.1 --- Degradation of MV under visible light --- p.60 / Chapter 4-2 --- Effects of the UV irradiation on MV --- p.64 / Chapter 4-3 --- Degradation of MV dye using M0O3 under UV light --- p.65 / Chapter 4.4 --- Mechanism of photocatalysis --- p.69 / References --- p.70 / Chapter Chapter 5 --- Conclusions and future work --- p.72 / Chapter 5.1 --- Conclusions --- p.72 / Chapter 5.2 --- Future work --- p.73 / References --- p.74
13

Photoabsorption of ultraviolet light by molecular oxygen : the Schumann-Runge bands and the Lyman-[alpha] window.

Gies, Hans Peter Friedrich January 1979 (has links)
156 leaves : tables, graphs ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1980
14

Photoabsorption of ultraviolet light by molecular oxygen : the Schumann-Runge bands and the Lyman-[alpha] window.

Gies, Hans Peter Friedrich. January 1979 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Physics, 1980.
15

Caractérisation de nouveaux borates pour le doublage de fréquence aux longueurs d'ondes VUV : endommagement optique / Characterization of news borates for the frequency-doubling at wavelengths VUV : optical damage

Bourezzou, Mourad 19 June 2013 (has links)
Le sujet de la thèse initié dans le cadre de l'ANR UV-Borate s'inclut dans le projet UV-Conversion labellisée par 2 pôles de compétitivité (Matériala - Lorraine - et Route des lasers - Aquitaine -) soumis à l'ANR en 2011. Les études se portent particulièrement sur les borates YxLaySc4-(x+y)(BO3)4 (LYSB) et YAl3(BO3)4 (YAB), cristaux Optiques Non Linéaires (ONL) possédant la même structure cristallographique (R32). La croissance de ces cristaux est effectuée par les collaborateurs industriels et universitaires de l'ANR. Ces deux matériaux présentent en effet des possibilités de conversion de fréquence jusqu'à des longueurs d'onde λ < 300 nm, de plus une non hygroscopicité procure une plus grande durée de vie des échantillons et par conséquent un net intérêt pour les applications industrielles. L'endommagement laser étant lié à l'absorption et ainsi, en partie, aux impuretés, une étude de la qualité cristalline et de l'homogénéité de nos cristaux a été effectuée. Les résultats ont permis de relier des défauts de structure (dislocations et etch pits) à la croissance de la maille rhomboédrique via des caractérisations par ombre portée (Photography Schlieren) et par attaque chimique suivi d'une observation par microscopie optique, MEB et MFA. Par ailleurs, des études théoriques et expérimentales d'accord de phase (détermination de Θ et φ) lors de conversions de type I principalement ont été réalisées sur les cristaux de YAB, LYSB ainsi que sur des cristaux de référence tel que ß-BaB2O4 (ß-BBO). L'aspect de l'endommagement laser dans les matériaux ONL a été abordé dans les locaux de l'Institut Fresnel de Marseille au sein de l'équipe Interaction Laser Matière (ILM) sur des échantillons de Li2B4O7 (LTB). L'équipe a effectivement développé un dispositif de mesure de la probabilité d'endommagement laser et de mesure de tenue du seuil d'endommagement laser des matériaux optiques. Par ailleurs, un effort a été mené dans la conception d'un dispositif de mesure de la transmission optique et absorption à température ambiante et aux basses températures afin de révéler des défauts absorbants. Des premiers résultats ont été obtenus et discutés sur des échantillons de ß-BBO et LYSB / The purpose of my thesis, performed within the program of the ANR UV-Borate, was integrated in the UV-Conversion project certified by 2 poles of competitiveness (Matériala - Lorraine - and Route des lasers - Aquitaine -). The project concerned the study of borates YxLaySc4-(x+y)(BO3)4 (LYSB) and YAl3(BO3)4 (YAB), Non-Linear Optical (NLO) crystals which have the same crystallographic structure (R32). The growth of the crystals was realized by industrials and academics collaborators of the ANR. Those two materials present possibilities of frequency conversion until wavelengths λ < 300 nm. Because they are not hygroscopic, they have a bigger time life compare to other materials which offer a most important interest for the industrial applications. We have studied the quality and the homogeneity of our crystals. Indeed, the use of strong optical beam can lead to damages on the crystal and degrade the properties of the materials which are related to the absorption and to impurities of the crystals. Our results allowed to related defaults in the structure (dislocations and etch pits) to the growth of the rhombohedral crystal system by using characterization techniques as the "Photography Schlieren" or optical microscopy (before which a "Chemical Etching" was performed) or by using SEM and AFM. In the fridge of the previous work, theoretical and experimental phase matching studies (determination of Θ and φ) during conversions of frequency of type I were realized on the YAB and LYSB crystals and on the reference crystals such as ß-BaB2O4 (ß-BBO). The aspect of optical damage was investigated at the Institut Fresnel of Marseille in the team Intéraction Laser Matière (ILM). The team has developed a device to measure the Laser Induced Damage (LID) probability and to measure of the Laser Induced Damage Threshold (LIDT) of optical materials. Laser-Induced-Damages studies in NLO materials were also realized on Li2B4O7 (LTB) samples. A strong effort was performed in the design of a device for the measurement of the optical transmission and the absorption at room temperature and low temperatures to reveal absorbent defaults. First state-of-art results were obtained and discussed for ß-BBO and LYSB samples
16

Study of surface enhanced resonance Raman scattering of crystal violet in colloidal silver. / 銀膠媒介內結晶紫的表面增強共振拉曼散射研究 / Study of surface enhanced resonance Raman scattering of crystal violet in colloidal silver. / Yin jiao mei jie nei jie jing zi de biao mian zeng qiang gong zhen la man san she yan jiu

January 2005 (has links)
by Wong Chun Wing = 銀膠媒介內結晶紫的表面增強共振拉曼散射研究 / 黃振榮. / Thesis submitted in: December 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 74-79). / Text in English; abstracts in English and Chinese. / by Wong Chun Wing = Yin jiao mei jie nei jie jing zi de biao mian zeng qiang gong zhen la man san she yan jiu / Huang Zhenrong. / Abstract --- p.1 / Chapter Chapter 1 --- Introduction --- p.2 / Chapter Chapter 2 --- Experimental Setup --- p.7 / Chapter 2.1 --- Raman probe --- p.7 / Chapter 2.2 --- Spectrophotometer for absorption spectra --- p.7 / Chapter 2.3 --- TEM and AFM --- p.8 / Chapter Chapter 3 --- Sample Preparation --- p.9 / Chapter 3.1 --- Chemicals --- p.9 / Chapter 3.2 --- Silver Colloid --- p.9 / Chapter 3.3 --- Slide Coated with Silver Colloid --- p.10 / Chapter 3.4 --- Sampling Probe --- p.10 / Chapter Chapter 4 --- Results and Discussion --- p.12 / Chapter 4.1 --- Dependence of SERRS on CV Concentration --- p.12 / Chapter 4.1.1 --- Resonant Raman spectra of CV --- p.12 / Chapter 4.1.2 --- TEM Images of Ag Colloid --- p.17 / Chapter 4.1.3 --- SERRS at different CV Concentrations in Solution --- p.20 / Chapter 4.2 --- Dependence of CV SERRS on Ag Concentration --- p.36 / Chapter 4.3 --- Dependence of CV SERRS on NaCl Concentration --- p.42 / Chapter 4.3.1 --- UV-VIR Absorption Spectra of NaCl added Ag Colloid --- p.42 / Chapter 4.3.2 --- Dependence on NaCl Concentration --- p.49 / Chapter Chapter 5 --- Conclusions --- p.64 / Appendix A / Chapter A.1(part A) --- Estimation of the Number Density of Colloidal Ag Particles --- p.66 / Chapter A.1(part B) --- Estimation of CV Concentration needed for Monolayer Coverage on Ag colloids --- p.67 / Chapter A.2 --- Assignments of Crystal Violet (CV) Vibrational Modes --- p.69 / Appendix B Estimation of the Probed Volume of the Microscope Objective --- p.70 / Appendix C Estimation of the Effective Molar Absorption Coefficient (α) of CV --- p.71 / References --- p.74
17

History and development of the viola d'amore

Durkin, Rachael January 2015 (has links)
The viola d’amore is a small bowed instrument that was in use predominantly from the second half of the seventeenth century to the end of the eighteenth. Initially, the name viola d’amore referred to a treble viol strung with wire strings, but it underwent a transformation c.1700 with the addition of sympathetic strings, with the bowed strings changing from wire to gut. The history of the viola d’amore centres on German-speaking regions of Europe, with the cultivation of the sympathetic strings stemming from Austria. While originally reserved for the wealthiest classes, evidence suggests that the viola d’amore became a widely used instrument due to the number of extant instruments in collections today. Due to the viola d’amore existing in two forms, the historical and organological context of the instrument is of paramount importance. Thus, this thesis addresses not only the viola d’amore in both its forms, but also its predecessors, the baryton and the englische violet, charting their development and ultimate influence on the invention of the viola d’amore with sympathetic strings. The suggested line of evolution is supported by measurements and observations of construction of the individual instruments, as well as physical examinations of extant specimens, and is considered in light of relevant iconography, music scores, newspaper advertisements and literary references. The research has led to the redrawing of parameters for each instrument, clearly defining the instruments’ functions and notable attributes. This thesis is the first complete organological study of the viola d’amore and other bowed instruments with additional wire strings. It presents a comprehensive review of the associated literature for each instrument concerned, as well as measurements and organological observations, with particular emphasis on design and construction. Additionally, it also considers the development of wire-strung instruments in England, briefly including: native music wire-drawing; the existence of other instruments with the name ‘d’amore’ and its variations; and lesser considered instruments with sympathetic strings such as the hardanger fiddle and trumpet marine. Finally, the conclusion is drawn that the viola d’amore with sympathetic strings may be considered as the epitome of Baroque instrumental design.
18

WiggleZ: Survey design and star-formation in UV-luminous galaxies

Russell Jurek Unknown Date (has links)
The WiggleZ Dark Energy survey is currently being carried out using the AAOmega instrument on the AAT. It is measuring redshifts for 240,000 emission line galaxies with high star-formation rates over 1,000 sq. degrees of sky. These galaxies are selected for spectroscopic observation from a combination of optical and ultraviolet imaging. The target selection criterion applied to these datasets is highly optimised to select high redshift emission line galaxies. The redshift distribution of these galaxies peaks at z
19

Phosphor Coated UV-Responsive CCD Image Sensors

Alexander, Stefan January 2002 (has links)
Typical CCD image sensors are not sensitive to Ultra-Violet (UV) radiation, because the UV photons have a penetration depth of 2nm in the ~1&micro;m thick polysilicon gate material. An inorganic phosphor coating was developed previously (by Wendy Franks et al [1, 2]) that was shown to be a viable solution to creating a UV-sensitive CCD image sensor. The coating absorbs incident UV radiation (250nm) and re-emits it in the visible (550-611nm) where it can penetrate the gate material. This coating was deposited using a settle-coat type deposition. Improved coating techniques are presented here. These include a commercial coating from Applied Scintillation Technologies (AST), a Doctor-Blade coating, e-beam deposition, and laser ablation. The properties of the coating, and of the coated sensors are presented here. Tests performed on the sensors include Quantum Efficiency, Photo-Response Non-Uniformity, Contrast Transfer Function, and Lifetime. The AST coating is a viable method for commercial UV-responsive CCD image sensors. The Doctor-Blade coatings show promise, but issues with clustering of the coating need to be resolved before the sensors can be used commercially. E-beam deposition and laser ablation need further research to provide a viable coating.
20

Phosphor Coated UV-Responsive CCD Image Sensors

Alexander, Stefan January 2002 (has links)
Typical CCD image sensors are not sensitive to Ultra-Violet (UV) radiation, because the UV photons have a penetration depth of 2nm in the ~1&micro;m thick polysilicon gate material. An inorganic phosphor coating was developed previously (by Wendy Franks et al [1, 2]) that was shown to be a viable solution to creating a UV-sensitive CCD image sensor. The coating absorbs incident UV radiation (250nm) and re-emits it in the visible (550-611nm) where it can penetrate the gate material. This coating was deposited using a settle-coat type deposition. Improved coating techniques are presented here. These include a commercial coating from Applied Scintillation Technologies (AST), a Doctor-Blade coating, e-beam deposition, and laser ablation. The properties of the coating, and of the coated sensors are presented here. Tests performed on the sensors include Quantum Efficiency, Photo-Response Non-Uniformity, Contrast Transfer Function, and Lifetime. The AST coating is a viable method for commercial UV-responsive CCD image sensors. The Doctor-Blade coatings show promise, but issues with clustering of the coating need to be resolved before the sensors can be used commercially. E-beam deposition and laser ablation need further research to provide a viable coating.

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