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1
Laschewsky, André. "Oligoethyleneoxide spacer groups in polymerizable surfactants." Universität Potsdam, 1991. http://opus.kobv.de/ubp/volltexte/2008/1722/.
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Cationic and zwitterionic polymerizable surfactants bearing tri- and tetraethyleneglycol spacer groups between the polymerizable moiety and the surfactant structure were prepared and polymerized. Monomers and polymers were investigated with respect to their aggregation behavior in aqueous systems and compared to analogous monomers and polymers lacking spacer groups. In the case of the monomeric surfactants, the spacer groups depress both the Kraffttemperature and the critical micelle concentration. the area occupied per molecule at the air-water interface is substantially enlarged by the spacers, whereas the depression of surface tension is nearly constant. Although the monomers with and without spacers are true surfactants, all the polymers are water-insoluble, but form monomolecular layers at the air-water interface. In analogy to the monomer behavior, the incorporation of the spacer groups increases the area occupied per repeat unit at the air-water interface substantially, but hardly affects the surface activity.
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Rowehl, Jill A. (Jill Annette). "Organic multilayer photoconductor utilizing a spacer layer." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/57977.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 61-62).
Chemosensors hold many vital applications in today's world, particularly as detectors for explosives. There is still vast room for improvement as other technologies-particularly those of explosives-continue to evolve and expand. Herein, we develop a novel device structure with the potential for much higher sensitivity. The lateral bilayer photoconductor is comprised of an exciton generation layer (EGL) and a charge transport layer (CTL). This separates the functionality of chemical sensing from the charge transport, allowing each film to be independently optimized. As a further improvement on this structure, we introduce a spacer layer to separate charge carriers in the EGL and the CTL, reducing bimolecular recombination at the interface. As a proof of concept, we fabricate and characterize lateral multilayer photoconductors composed of small molecule organic films. It is experimentally demonstrated that the utilization of a spacer layer can produce an order of magnitude enhancement in quantum efficiency over the of a spacer layer can produce an order of magnitude enhancement in quantum efficiency over the The work reported here provides encouraging results in the fields of chemosensors and organic optoelectronics.
by Jill A. Rowehl.
S.B.
3
Chikka, Avanthi. "Biomechanical Evaluation of a Lumbar Interspinous Spacer." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1302258049.
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Verkooijen, Katharine Mary. "Tears of the sun : Bronze Age amber spacers from Britain and Europe." Thesis, University of Exeter, 2013. http://hdl.handle.net/10871/15028.
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The amber spacers from Bronze Age Britain and Europe are one of the most well known artefact groups from this time period. Yet despite the frequency with which these artefacts are cited, the details of these finds both individually and within their original excavation contexts appear to be poorly understood. Recent new finds of ‘sets’ of spacers prompted this review and updating of the amber spacer corpus, which now extends to 375 individual spacers from 141 findspots. Once thought to constitute an artefact horizon which could provide a chronological bridge between the regions of Northwest Europe and Britain / the Central European Únĕtice/Tumulus Cultures and Late Helladic I and II Mycenaean Greece, new radiocarbon dating programs have extended their date range from (potentially) c. 2000 cal B.C. to c.1360 cal. B.C., although the regional chronologies remain essentially unresolved. To give a clear survey of how the spacers have been viewed historically, the catalogue entry for each findspot/spacer includes, as well as information about the findspots themselves, x-rays, photographs and drawings produced for this research, alongside all the previously published quotes and illustrations. Microscopic analyses provide evidence for some spacer-sets having been fragmented and deposited separately. Maps showing illustrations of the spacers where they were recovered allow comparison of regional similarities and differences. Loose colour plates show the x-rays of groups of spacers which have been correlated in past interpretations at 1:1 scale for easy comparison. Some earlier interpretations, including the Crescentic/Pendant regional division, the jet spacer/amber spacer/lunulae discrete distribution pattern and the close relationship of the Basic Pattern spacers, are challenged and found to no longer be sustainable. The craft and production aspects of spacer manufacture, particularly the procurement of suitable raw material, are addressed and a new narrative is presented, which is partly informed by the experimental replica research.
5
Medvedeva, Sofia. "Natural Diversity of CRISPR Spacers." Electronic Thesis or Diss., Sorbonne université, 2019. http://www.theses.fr/2019SORUS538.
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Le système CRISPR-Cas est un système immunitaire procaryote de type interférence ARN dirigé contre des éléments génétiques mobiles, tels que les virus et les plasmides. Le système consiste en un ou plusieurs loci CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats ; courtes répétitions palindromiques groupées et régulièrement espacées) associés à des protéines Cas (CRISPR-associated proteins) dont ils sont séparés par une séquence dite leader. Toutes les protéines Cas peuvent être fonctionnellement attribuées à des modules d'adaptation, d'expression et d'interférence. L’analyse des spacers CRISPR est une précieuse source d’informations sur les interactions virus-hôte, puisqu’ils correspondent à de courts fragments d’ADN de virus précédemment rencontrés et « enregistrés » dans les loci CRISPR. La comparaison des spacers environnementaux les uns avec les autres et avec des spacers de bases de données ainsi que des séquences de virus nous a permis de tirer plusieurs conclusions : 1) Une dynamique à long terme des spacers CRISPR I-E de E. coli a été étudiée en comparant la diversité des spacers dans les génomes publiés d'E. coli avec des spacers amplifiés à partir du contenu intestinal de mammouth. 2) Les spacers du CRISPRome des communautés naturelles de Thermus, Sulfolobus et Flavobacteries ciblent de préférence des virus isolés de la même source, avec différents systèmes CRISPR-Cas ciblant différents virus. 3) Les données CRISPRome de Flavobacterium et Sulfolobus (Chapitres II et IV) montrent un schéma phylogéographiqueCRISPR-Cas is a prokaryotic immunity system against mobile genetic elements, such as viruses and plasmids. The system consists of two components: the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (Cas). In the CRISPR array, short fragments of foreign DNA, called spacers, are interleaved with palindromic repeats. During the adaptation stage of the CRISPR-Cas immunity, new spacers are inserted into the CRISPR array, whereas during the expression and interference stages, spacers are transcribed, processed and complexed with Cas proteins to target the complementary foreign DNA or RNA molecules for degradation. Analysis of CRISPR spacers is a valuable source of information about virus-host interactions, particularly powerful when applied to metagenomic data. In this work, we explored the diversity of CRISPR spacers in different natural prokaryotic communities, including extinct Escherichia coli community from a mammoth intestine, Flavobacterium communities from Antarctic surface snow, Thermus communities from four distant hot springs in Italy and Chile, and Sulfolobales community from a Japanese thermal field. The comparison of obtained environmental spacer sets with each other and with spacers from public databases as well as with sequences of viruses allowed us to reach several non-trivial conclusions and to gain insights into virus-host and virus-virus interactions in natural microbial communities
6
Sarrazin, Aurélien. "Développement de techniques de patterning avancées pour les filières CMOS-sub 10nm." Thesis, Nantes, 2017. http://www.theses.fr/2017NANT4017/document.
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Pour les technologies CMOS sub-10 nm, l’industrie du semi-conducteur est confrontée aux limites de résolution de la lithographie conventionnelle. Différentes techniques alternatives ont été proposées afin de permettre l’obtention de motifs avec des dimensions de l’ordre de 20 nm. Dans cette thèse, nous nous sommes intéressés au « spacer patterning » et à l’autoassemblage dirigé des copolymères à blocs. Nous avons développé une intégration de « spacer patterning » permettant l’obtention de lignes de 20 nm de largeur. Une étude a été menée à partir des matériaux disponibles au CEA-LETI. Ainsi, nous avons étudié les différents enjeux de cette intégration pour les prochains nœuds technologiques. Pour l’auto-assemblage dirigé des copolymères à blocs (DSA), un des enjeux concerne la création d’un masque avec le retrait d’un polymère sélectivement à l’autre. Dans le cadre de notre étude sur le PS-b-PMMA, nous nous sommes intéressés au retrait du PMMA sélectivement au PS par gravure plasma. Des chimies par plasma permettant le retrait du PMMA sélectivement au PS pour des motifs cylindriques et lamellaires ont été développéesFor sub-10 nm CMOS technologies, the semiconductor industry is facing the limits of conventionnal lithography. Several alternative techniques have been proposed to allow 20 nm patterns. In this thesis, we have proposed to focus on spacer patterning technique and Directed Self-Assembly of block copolymers (DSA). We have developped a spacer patterning integration which allows to pattern 20 nm-wide lines. A study has been carried out with materials available at CEA-LETI. Thus, we have studied the different challenges induced by this integration for the following technologic nodes. Concerning Directed Self-Assembly of block copolymers (DSA) technique, one of the main challenge concerns the mask creation by removing a polymer selectively to another. For our study on PS-b-PMMA, we have studied PMMA removal selectively to PS by plasma etching. Plasma chemistries have been developed for removing PMMA selectively to PS on cylidrical and lamellar patterns
7
Mian, Alec. "Molecular evolution in the rDNA multigene family." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282909.
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Cheung, Mei, and 張微. "Internal transcribed spacer as the DNA barcode for pathogenic fungi." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206495.
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Identification of pathogenic fungi isolated from clinical specimens in clinical microbiology laboratories is primarily based on observing fungal phenotypic structures under the microscope and performing biochemical tests for fungal cultures. This conventional method is very time-consuming and labor-dependent. It usually requires several weeks for the fungi to grow sufficiently on culture media, and the identification processes on fungal phenotypic structure rely very much on experienced staff. Therefore, a more accurate and rapid method for pathogenic fungal identification is necessary for clinical laboratories to get abreast of modern development.
Gene sequencing and phylogenetic analysis targeting the internal transcribed spacer (ITS) region in the fungal genomes are the most commonly used molecular methods for fungal identification. Because of the optimal inter and intra-species variation property of the ITS region, it can act as the DNA barcode to identify fungi to the species level. In this study, 33 clinical fungal isolates were identified by both phenotypic method and ITS sequencing. The results showed that 23 isolates were successfully identified to thespecies level by both phenotypic and molecular methods. Moreover, five isolates were only identified to the genus level by phenotypic method, but they could be successfully identified to the species level by ITS sequencing. However, five isolates have not been differentiated because there were mismatched results from phenotypic and sequencing methods. It may be due to the limitation of sequencing method on some fungal species. Building up a more comprehensive database or setting up a standard platform to guide the molecular process may help improve the performance of molecular method.
To conclude, molecular method is a rapid and reliable way for fungal identification because ITS region acts as the DNA barcode for pathogenic fungi.published_or_final_version
Medical Sciences
Master
Master of Medical Sciences
9
Sobottke, Rolf [Verfasser]. "Der interspinöse Spacer als Therapieoption bei lumbaler Spinalkanalstenose / Rolf Sobottke." Köln : Deutsche Zentralbibliothek für Medizin, 2011. http://d-nb.info/1010971697/34.
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Mateos, Mariana, and Therese Markow. "Ribosomal intergenic spacer (IGS) length variation across the Drosophilinae (Diptera: Drosophilidae)." BioMed Central, 2005. http://hdl.handle.net/10150/610372.
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BACKGROUND:The intergenic spacer of the ribosomal genes in eukaryotes (IGS) contains duplications of the core transcription promoter. The number of these duplicated promoters, as measured by the IGS length, appears to be correlated with growth rate and development time in several distantly related taxa. In the present study, we examined IGS length variation across a number of species of Drosophila to determine the amount of variation in this trait across different evolutionary time scales. Furthermore, we compared the usefulness of two methods commonly used to determine IGS length: Southern Blot Hybridization (SB) and Polymerase Chain Reaction (PCR).RESULTS:Our results show broad variation in IGS length across the genus Drosophila, but closely related species had similar IGS lengths. Our results also suggest that PCR tends to underestimate the true IGS size when the size is greater than 5 kb, and that this degree of underestimation is greater as the IGS size increases.CONCLUSION:Broad variation in IGS length occurs across large evolutionary divergences in the subfamily Drosophilinae. Although average IGS length has been shown to evolve rapidly under artificial selection, closely related taxa generally have similar average IGS lengths. Our comparison of methods suggests that without previous knowledge of the DNA sequence of the IGS and flanking regions, both methods be used to accurately measure IGS length.
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Bodo, Slotta Tracey A. "Phylogenetic Analysis of Iliamna (Malvaceae) Using the Internal Transcribed Spacer Region." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/33211.
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The genus Iliamna Greene has a taxonomically complex history. Since its desciption in 1906, the genus was not recognized for some time, several species were initially placed into other genera, and the species status of a few was questioned. Today, eight species of Iliamna are recognized. Six species are located in western North America and two are found isolated to the east. Species in Iliamna are very similar morphologically with only a few characters distinguishing several as separate entities. The need for systematic study became apparent since all but one species are considered rare or endangered. Also, the differentiation between two endangered species, I. corei and I. remota, was unclear in a previous study using random amplified polymorphic DNA fragments. Of the western species, four overlap in distribution (I. crandallii, I grandi ora, I. longisepala, and I. rivularis) and their recognition as separate species has been questioned. The focus of this study was to develop a phylogeny for Iliamna using sequences from the internal transcribed spacer region (ITS) of the nuclear ribosomal
RNA genes in order to determine its biogeographical and evolutionary history. Cladistic analysis was performed and the resulting phylogeny is presented. The ITS data provide new insights in the origination of the genus and its distribution. In Iliamna, the ITS region is 677 base pairs long with 120 sites providing information in the formation of phylogenetic trees. Iliamna forms a well-supported clade distinct from related genera and is monophyletic. Three well-supported groups are formed. One contains representatives from the Pacific Northwest. Another contains all of the remaining species with the third clade nested therein. This last clade contains the two eastern species, I. corei and I. remota, but there is not enough variability to support the divergence of these taxa as distinct species. There is also not sufficient variability in the ITS region to identify the western species I. crandallii, I. grandi ora, I. longisepala and I. rivularis as distinct entities.Master of Science
12
Iranshahi, Ashkan. "Static Mixing Spacers for Spiral Wound Modules." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1352121892.
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Bakker, Frederik Theodoor. "Time spans and spacers: molecular phylogenetic explorations in the Cladophora complex (Chlorophyta) from the perspective of rDNA gene and spacer sequences." [S.l. : [Groningen] : s.n.] ; [University Library Groningen] [Host], 1995. http://irs.ub.rug.nl/ppn/141166363.
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Chelaru, Liviu Ionut. "Microscopic studies of interlayer magnetic coupling across nonmagnetic and antiferromagnetic spacer layers." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970939299.
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Zhou, Jianping. "A study of charge accumulation and spacer flashover in compressed gas insulation." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/32116.
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Compressed gas insulated substation (GIS) and transmission line (GITL) equipment have been developed rapidly throughout the world during the past decades. Compactness is the main advantage of GIS and GITL over conventional air-insulated substations and transmission lines. Sulphur hexafluoride (SF₆) is used as an insulation gas in GIS and GITL because of its excellent insulating properties. Supporting spacers are identified as the most likely places for flashover to occur and they often determine the overall strength of a system. For energized system, surface charges have been observed on spacer surfaces and are considered to play an important role for anomalous flashover of a GIS or GITL system. The purpose of this research is to study the mechanisms and factors governing the magnitude and distribution of surface charges and their influence on flashover voltage.
In this investigation, experiments to study surface charge accumulation under different experimental conditions have been conducted, with a rod-spacer-plane electrode system. The parameters varied are applied voltage levels, insulating gases, gas pressures, spacer materials, rod electrode diameters, and the duration of applied voltages. Experiments with impulse voltage pre-charging were also conducted. It was found that the mechanisms of surface charging are corona, gas conduction, and photoionization. Surface charge magnitude and distribution
are strongly field dependent and are related to the duration of voltage application. Spacers in SF₆ gas accumulate less charges on the surface than in air and nitrogen , for a given geometry, spacer material, voltage, and gas pressure.
In order to determine the effect of surface charges on overall electric field, a surface charge simulation program (the SSM program) was developed to calculate the overall electric field when there are surface charges on a spacer surface. The calculation results show that surface charges significantly distort the overall electric field magnitude, field direction, and distributions, which may explain the anomalous flashover in GIS/GITL systems. It was found that the flashover propagation field on a PTFE spacer surface may be between 6 kV/cm and 10 kV/cm.
High speed photographic observations, with an image intensifier, are suggested
to examine the propagation of a flashover. It may, therefore, be possible that, a reasonable model to predict flashover in SF₆ gas can be built by comparing the flashover propagation model with the electric field pattern on a spacer surface.
The role of photoionization near the spacer surface in charge accumulation should also be studied in greater detail.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Ford, Lorelei Melissa. "SEQUENCE ANALYSIS OF THE 16S-23S INTERGENIC SPACER REGIONS OF FLAVOBACTERIUM COLUMNARE." MSSTATE, 2008. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06232008-152814/.
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The 16S, 23S, and 5S ribosomal RNA (rRNA) genes are highly conserved sequences in bacteria. For this reason, rRNA genes are often used for phylogenetic classification. On the other hand, the regions between the structural sequences, known as intergenic spacer regions (ITS), are under less evolutionary pressure to be conserved. Because they are not as highly conserved, they can be used to differentiate strains of the same bacterial specie. The purpose of this study was to evaluate the 16S-23S ITS of Flavobacterium columnare, an important pathogen of cultured fish, by comparing the 16S-23S ITS sequences from 70 isolates. We developed two PCR assays that amplify overlapping regions of one large previously identified ITS. The primers targeted the 16S sequence and isoleucine tRNA encoding sequences and the 23S sequence and alanine tRNA encoding sequences. The PCR products were cloned and sequenced. We also targeted I-CeuI restriction fragments from the ATCC type strain that were separated by pulse field gel electrophoresis and analyzed the 16S-23S ITS regions. We found that the genome of this species harbors at least 6 intergenic spacer regions that are very similar and contain the same tRNA encoding sequences. This suggests that earlier studies that used the ITS for distinguishing between strains of Flavobacterium columnare may be comparing sequences from different structural RNA operons and thus have misleading data.
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Graham, Thomas A., and University of Lethbridge Faculty of Arts and Science. "Characterization of the 16S/23S ribosomal RNA intergenic spacer regions of Listeria." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 1995, 1995. http://hdl.handle.net/10133/26.
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The 16S/23S ribosomal RNA (rRNA) intergenic space (IGS) regions from pathogenic and non-pathogenic species (spp.) of Listeria were characterized by the polymerase chain reaction (PCR) and DNA sequencing. DNA sequencing data for the small rRNA IGS region showed that this IGS was approximately 244 bp in length and was highly homologous (95 to 99 %) in five of the six Listeria spp examined; ie., L. monocytogenes, L. innocua, L. seeligeri, L. welshimeri, and L. ivanovii. A lower degree of homology (91 to 94 %) was detected in the large rRNA IGS region (ca. 494 bp) of these species. The DNA sequence data was used to develop two sets of oligonucleotide primers for PCR-based detection of the members of the genus Listeria. The first set of primers were Listeria genus-specific and, the second set of primers were L. monocytogenes-specific.xv, 131 leaves ; 29 cm.
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Dzemiantsova, Liudmila [Verfasser]. "Magnetic Coupling of Individual Atoms through Non-magnetic Spacer Layers / Liudmila Dzemiantsova." München : Verlag Dr. Hut, 2013. http://d-nb.info/1031844872/34.
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Northwood, Ewen Jody. "Cartilage wear simulation models for surface and spacer hemiarthroplasty and tissue engineering." Thesis, University of Leeds, 2007. http://etheses.whiterose.ac.uk/12733/.
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Understanding the wear of the biomaterial/cartilage interface is vital in the development of more satisfactory materials for use in the clinical repair of worn or damaged synovial joints. The aims of this study were to investigate a wide range of biphasic hydrogels as potential chondroplasty materials and to further the understanding of natural joint tribology. The mechanical properties of each potential chondroplasty material were quantified and their tribological performance investigated by means of a series of simple geometry friction and wear studies in Ringer's solution and a proteincontaining lubricant. Also uni- and multi-directional continuous sliding tests in a protein-containing lubricant were conducted under various loading conditions to evaluate the friction and degradation of each material and that of the opposing articular cartilage surface. A number of potential chondroplasty materials were also evaluated as defect repair materials when implanted using a proposed clinical method. Selected biphasic hydrogel materials showed a marked reduction in dynamic friction, degradation and articular cartilage pin damage when compared with single-phase materials. Following continuous wear studies, alterations in opposing cartilage surface topography were found to be associated with increased levels of dynamic friction. The protocols devised in this study are the first to yield objective and quantifiable data demonstrating a reduction in friction and opposing cartilage surface degradation following the implantation of certain biphasic hydrogel defect repair materials. They also demonstrate the potential of biphasic hydrogels to act as superior chondroplasty materials compared with currently available materials. Future work will focus on the optimisation of biphasic hydrogel properties, including the long-term durability and immunogenicity of each material following implantation, in order that materials will more closely mimic the tribology of natural articular cartilage.
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Nicolas, Rana. "Squeezing light in nanoparticle-film plasmonic metasurface : from nanometric to atomically thin spacer." Thesis, Troyes, 2015. http://www.theses.fr/2015TROY0028/document.
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Les plasmons polaritons de surface (SPP) et les plasmons localisés de surface (LSP) font l’objet de nombreuses investigations du fait de leur fort potentiel technologique. Récemment, une attention particulière a été portée à des systèmes supportant ces deux types de résonances en déposant des nanoparticules (NPs) métalliques sur des films minces métalliques. Plusieurs études ont mis en évidence le couplage et l’hybridation entre modes localisés et délocalisés. Cependant, une compréhension en profondeur des propriétés optiques et du potentiel de ces interfaces est toujours manquante. Nous avons mené ici une étude de systèmes NPs/film couplés. Nous avons étudié à la fois expérimentalement et théoriquement l’influence d’une couche séparatrice ultra-mince en SiO2 ainsi que l’évolution des différents modes plasmoniques pour différentes épaisseurs. Nous avons ainsi mis en lumière que de tels systèmes couplés offrent des propriétés optiques exaltées et une large accordabilité spectrale. Nous avons aussi cherché à diminuer l’épaisseur de la couche séparatrice vers le cas ultime monoatomique en utilisant le graphène. Du fait du caractère non-diélectrique de celui-ci, nous avons mis en évidence un comportement optique inattendu de la résonance plasmonique. Nous avons expliqué celui-ci par la mise en évidence du dopage du graphène par les NPs, ce qui est un premier pas en direction de dispositifs optoélectroniques à base de graphène. Enfin, après avoir amélioré notre compréhension théorique de ces systèmes, nous avons évalué leur potentiel comme capteurs SERS ou LSPSurface plasmon polariton (SPP) and Localized surface plasmon (LSP) have attracted numerous researchers due to their high technological potential. Recently, strong attention was paid to the potential of SPP and LSP combinations by investigating metallic nanoparticles (NPs) on top of metallic thin films. Several studies on such systems have shown the coupling and hybridization between localized and delocalized modes. In this work, we propose a full systematic study on coupled NP/film systems with Au NPs and Au films. We investigate both experimentally and theoretically the influence of an ultra-thin SiO2 dielectric spacer layer, as well as the evolution of the plasmonic modes as the spacer thickness increases. We show that coupled systems exhibit enhanced optical properties and larger tunability compared to uncoupled systems. We also compare these results with those measured for coupled interfaces using graphene as a non-dielectric sub-nanometer spacer. Introducing graphene adds complexity to the system. We show that such coupled systems also exhibit enhanced optical properties and larger tunability of their spectral properties compared to uncoupled systems as well as unexpected optical behavior. We explain this behavior by evidencing graphene doping by metallic NPs, which can be a first step towards graphene based optoelectronic devices. After establishing a deep understanding of coupled systems we perform both SERS and RI sensing measurements to validate the high potential of these plasmonic interfaces
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Wattebled, Laurent. "Oligomeric surfactants as novel type of amphiphiles : structure - property relationships and behaviour with additives." Phd thesis, Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2007/1285/.
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The properties of a series of well-defined new surfactant oligomers (dimers to tetramers)were examined. From a molecular point of view, these oligomeric surfactants consist of simple monomeric cationic surfactant fragments coupled via the hydrophilic ammonium chloride head groups by spacer groups (different in nature and length). Properties of these cationic surfactant oligomers in aqueous solution such as solubility, micellization and surface activity, micellar size and aggregation number were discussed with respect to the two new molecular variables introduced, i.e. degree of oligomerization and spacer group, in order to establish structure – property relationships. Thus, increasing the degree of oligomerization results in a pronounced decrease of the critical micellization concentration (CMC). Both reduced spacer length and increased spacer hydrophobicity lead to a decrease of the CMC, but to a lesser
extent. For these particular compounds, the formed micelles are relatively small and their aggregation number decreases with increasing the degree of oligomerization, increasing spacer length and sterical hindrance. In addition, pseudo-phase diagrams were established for the dimeric surfactants in more
complex systems, namely inverse microemulsions, demonstrating again the important influence of the spacer group on the surfactant behaviour.
Furthermore, the influence of additives on the property profile of the dimeric compounds was examined, in order to see if the solution properties can be improved while using less material. Strong synergistic effects were observed by adding special organic salts (e.g. sodium salicylate, sodium vinyl benzoate, etc.) to the surfactant dimers in stoichiometric amounts. For such mixtures, the critical aggregation concentration is strongly shifted to lower concentration, the effect being more pronounced for dimers than for analogous monomers. A sharp decrease of the surface tension can also be attained. Many of the organic anions produce viscoelastic solutions when added to the relatively short-chain dimers in aqueous solution, as evidenced by rheological measurements. This behaviour reflects the formation of entangled wormlike micelles due to strong interactions of the anions with the cationic surfactants, decreasing the curvature of the micellar aggregates. It is found that the associative behaviour is enhanced by dimerization. For a given counterion, the spacer group may also induce a stronger viscosifying effect depending on its length and hydrophobicity.
Oppositely charged surfactants were combined with the cationic dimers, too. First, some mixtures with the conventional anionic surfactant SDS revealed vesicular aggregates in solution. Also, in view of these catanionic mixtures, a novel anionic dimeric surfactant based on EDTA was synthesized and studied. The synthesis route is relatively simple and the compound exhibits particularly appealing properties such as low CMC and σCMC values, good solubilization capacity of hydrophobic probes and high tolerance to hard water. Noteworthy, mixtures with particular cationic dimers gave rise to viscous solutions, reflecting the micelle growth.Die Eigenschaften einer Reihe gut definierter neuer oligomerer Tenside (von Dimeren bis zu Tetrameren) wurden untersucht. Strukturell bestehen diese oligomeren Tenside aus einfachen monomeren kationischen Tensidfragmenten, die über die hydrophile Kopfgruppe (Tetraalkyl-Ammoniumchlorid) durch „Spacer“-Gruppen unterschiedlicher Natur und Länge miteinander verbunden/gekoppelt sind. Die Eigenschaften dieser kationischen oligomeren Tenside in wässriger Lösung wie Löslichkeit, kritische Mizellbildungskonzentration und Oberflächenaktivität, Mizellgröße und Aggregationszahl werden in Bezug auf die zwei neuen molekularen Variabeln (d.h. dem Oligomerisationsgrad und der Spacer-Gruppe) untersucht, um Struktur-Eigenschafts-Beziehungen abzuleiten. Die Erhöhung des Oligomerizationsgrads verringert stark die kritische Mizellbildungskonzentration (CMC). Eine kurze Spacer-Länge oder ein erhöhte Hydrophobie des Spacers erniedrigt die CMC ebenfalls, aber in einem geringeren Umfang. Die gebildeten Mizellen sind relativ klein und ihre Aggregationszahl nimmt mit zunehmendem Oligomerisationsgrad ab, genau wie mit zunehmender Spacerlänge oder sterischer Behinderung. Außerdem wurden Pseudo-Phasendiagramme für die Gemini-Tenside in komplexen Systemen, nämlich in inversen Mikroemulsionen untersucht. Auch hier zeigt die Spacer-Gruppe einen großen Einfluß auf das Tensidverhalten. Weiterhin wurde der Einfluss von Zusätzen auf das Eigenschaftsprofil der dimeren Tenside untersucht. Starke Synergien wurden beobachtet, wenn man spezielle organische Anionen (z.B. Natriumsalicylat, Natriumvinylbenzoat, etc.) zu den dimeren Tensiden in stöchiometrischen Mengen hinzugibt. Für solche Mischungen wird die Mizellbildungskonzentration stark zu niedrigen Konzentrationen verschoben, wobei der Effekt für die Dimere ausgeprägter als für die analogen Monomere ist. Eine Verringerung der Oberflächenspannung wird ebenfalls erreicht. Gemini-Tenside mit geeigneten Spacer-Gruppen bilden nach Zugabe ausgewählter organischer Anionen viskoelastische Lösungen, selbst wenn die dimeren Tenside nur über relativ kurz Alkylketten verfügen. Dies wurde mittels rheologischer Messungen gezeigt. Dieses Verhalten resultiert aus der Bildung langer Zylinder-Mizellen aufgrund der starken Wechselwirkung der Anionen mit den kationischen Tensiden, die die Krümmung der mizellaren Strukturen verringern. Es wurde auch festgestellt, dass das assoziative Verhalten durch die Dimerisation erhöht wird. Für ein gegebenes Gegenion kann die Spacer-Gruppe den verdickenden Effekt verstärken, in Abhängichkeit von seiner Länge und Hydrophobie. Als weitere Zusätze wurden entgegengesetzt geladene Tenside wurden mit den kationischen Dimeren kombiniert. Einige Mischungen mit dem käuflichen anionischen Tensid SDS bilden Vesikel in Lösung. Mit Blick auf diese katanionischen Mischungen wurde ein neues anionisches Gemini-Tensid, das auf EDTA basiert ist, synthetisiert und charakterisiert. Der Syntheseweg ist relativ einfach und das Tensid zeigt interessante Eigenschaften wie niedrige CMC- und scmc-Werte, gute Solubilisierungskapazität von hydrophoben Substanzen und hohe Toleranz gegen hartes Wasser. Mischungen dieses anionischen Tensids mit bestimmten kationischen Dimeren bilden visköse Lösungen, was ein starkes Mizell-Wachstum widerspiegelt.
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Caraghiaur, Garrido Diana. "Experimental Study and Modelling of Spacer Grid Influence on Flow in Nuclear Fuel Assemblies." Licentiate thesis, KTH, Physics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9983.
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The work is focused on experimental study and modelling of spacer grid influence on single- and two-phase flow. In the experimental study a mock-up of a realistic fuel bundle with five spacer grids of thin plate spring construction was investigated. A special pressure measuring technique was used to measure pressure distribution inside the spacer. Five pressure taps were drilled in one of the rods, which could exchange position with other rods, in this way providing a large degree of freedom. Laser Doppler Velocimetry was used to measure mean local axial velocity and its fluctuating component upstream and downstream of the spacer in several subchannels with differing spacer part. The experimental study revealed an interesting behaviour. Subchannels from the interior part of the bundle display a different effect on the flow downstream of the spacer compared to subchannels close to the box wall, even if the spacer part is the same. This behaviour is not reflected in modern correlations. The modelling part, first, consisted in comparing the present experimental data to Computational Fluid Dynamics calculations. It was shown that stand-alone subchannel models could predict the local velocity, but are unreliable in prediction of turbulence enhancement due to spacer. The second part of the modelling consisted in developing a deposition model for increase due to spacer. In this study Lagrangian Particle Tracking (LPT) coupled to Discrete Random Walk (DRW) technique was used to model droplet movements through turbulent flow. The LPT technique has an advantage to model the influence of turbulence structure effect on droplet deposition, in this way presenting a generalized model in view of spacer geometry change. The verification of the applicability of LPT DRW method to model deposition in annular flow at Boiling Water Reactor conditions proved that the method is unreliable in its present state. The model calculations compare reasonably well to air-water deposition data, but display a wrong trend if the fluids have a different density ratio than air-water.
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Elbert, R., André Laschewsky, and H. Ringsdorf. "Hydrophilic spacer groups in polymerizable lipids: formation of biomembrane models from bulk polymerized lipids." Universität Potsdam, 1985. http://opus.kobv.de/ubp/volltexte/2009/1736/.
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A variety of polymerizable lipids containing a hydrophilic spacer group between the reactive group and the main amphiphilic structure have been synthesized. They were investigated in monolayers, liposomes, and multilayers. When the spacer concept was used, efficient decoupling of the motions of the polymeric chain and the amphiphilic side groups is achieved. Thus, the often found loss of the important fluid phases by polymerization is avoided. Polymeric monolayers of the spacer lipid, prepared either by polymerization in the monolayer or by spreading of prepolymerized lipid, exhibit nearly identical
surface pressure-area diagrams. Most distinctly, the successful decoupling of the motions of the polymer main chain and the membrane forming amphiphilic side groups is demonstrated by the self-organization of bulk polymerized spacer lipids to polymeric liposomes. In addition, spacer lipids are able to build polymeric Langmuir-Blodgett multilayers. The decoupling of the polymer main chain and the membrane-forming amphiphilic side groups enables the deposition of already polymeric monolayers onto supports to form defined multilayers. If, alternatively, monomeric monolayers are deposited and polymerized on the support, defects in the layers due to structural changes during the polymerization are avoided by the flexible spacer group.
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Okubo, Hitoshi, Fumihiro Endo, Naoki Hayakawa, Hiroki Kojima, Kanako Nishizawa, and Diaa-Eldin A. Mansour. "Charge accumulation effects on time transition of partial discharge activity at GIS spacer defects." IEEE, 2010. http://hdl.handle.net/2237/14529.
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Okubo, Hitoshi, Fumihiro Endo, Naoki Hayakawa, Hiroki Kojima, and Diaa-Eldin A. Mansour. "Partial Discharges and Associated Mechanisms for Micro Gap Delamination at Epoxy Spacer in GIS." IEEE, 2010. http://hdl.handle.net/2237/14531.
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Okubo, Hitoshi, Masafumi Takei, Yoshikazu Hoshina, Masahiro Hanai, Katsumi Kato, and Muneaki Kurimoto. "Application of Functionally Graded Material for Reducing Electric Field on Electrode and Spacer Interface." IEEE, 2010. http://hdl.handle.net/2237/14528.
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Hao, Gang, and 郝剛. "Molecular phylogeny of the illiciales based on internal transcribed spacer sequences of ribosomal DNA." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31238567.
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Zhu, Fang. "Charge mechanisms for PTFE spacer service under DC and lightning impulse voltage in SF₆." Thesis, University of Strathclyde, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432015.
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Caraghiaur, Garrido Diana. "Expermintal study and modelling of spacer grid influence on flow in nuclear fuel assemblies /." Stockholm : Fysik, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9983.
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Hao, Gang. "Molecular phylogeny of the illiciales based on internal transcribed spacer sequences of ribosomal DNA /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21029027.
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Hille, Frank [Verfasser]. "Investigation of Spacer Acquisition Mechanisms in Type V-A CRISPR-Cas Systems / Frank Hille." Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1215570341/34.
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Chen, Pauli, and 陳銘仁. "Automatic Inspection for LCD Spacer." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/17090603920130858802.
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碩士義守大學
資訊工程學系
92
There are many categories for LCD used in electric and communication products. All of the manufacturers are trying to make mass and reliable products. In this study，we propose an automatic system to detect spacers and check the quality of LCD according to the amount of spacers. Sizes of the spacers are generally very small and dispersed in the LCD panel. Detecting the amount of spacers by human eyes is inefficient and un-precise. Automatic detection of LCD spacers based on image processing is proposed in this thesis. After Image processing，we count the amount of spacers and judge the quality of LCD. The gray histogram is first constructed based on YCbCr color space and smoothed by an average filter. Then a threshold is determined to segment the gray level image to a binary image. The segmentation results are poor when the image are partially highlighted or shaded in a few of uniform regions. We here propose a method using histogram thresholding based on the gray histogram smoothed by an average of seven points and the differentiation histogram by an average of five points. The shapes of spacers are then extracted by mathematical morphology method. Finally，we use chain code to obtain the amount of spacers. The performance of the image-based method is proved to be better that done by human eyes.
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Tai, Jung-Chi, and 戴榮吉. "Magnetic Tunnel Junction with Organic Spacer." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/80851164505234516457.
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碩士國立臺灣大學
物理研究所
95
We try to fabricate magnetic tunnel junctions with the organic spacer of molecules or polymers. There are four methods we use to form organic thin layer, and two of them could successfully be used to prepare tunnel junctions. They are the method of formation of Langmuir-Blodgett (LB) films of amphibious small molecules and the method of spin coating of polymers. The main goal of the experiments is to realize the tunnel magneto-resistance (TMR) effect in the organic junction, and to measure the electric, magnetic, surface, and chemical properties of the organic magnetic tunnel junction (OMTJ). We find the tunnel magneto-resistance effect of the organic magnetic tunnel junction with the organic spacer of Langmuir-Blodgett (LB) film, which is consistent with the magnetic configuration. In addition, we compare the TMR effect at different temperature and with different molecular layers.
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Su, Kai-Nung, and 蘇凱農. "Anodic Bonding Technique for Spacer Mounting." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/22473638216774390939.
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碩士國立交通大學
材料科學與工程系
89
Anodic Bonding Technique for Spacer Mounting Student：Kai-Nung Su Advisor：Dr. Pang Lin Institut of Materials Science and Engineering National Chiao Tung Univrsity Abstract The recently developed field emission display(FED) has several advantages ,such as light weight ,reduced lateral size ,short response time and low voltage ,over the traditional cathode ray tube(CRT) ,FED has a potential to replace CRT for a wide applications ,in the near future . For large-area FED ,spacers in between cathode and anode glass plate are needed for supporting and insulation. Therefore ,the mounting process of the spacers on the glass plates will be one of the critical fabrication techniques of FED. Fixing of spacers could be achieved by adhesion to melted glass frits ,which are initially mixed with organic solution ,then printed on the glass and melted after heat treatment at high temperature around 500 oC. The other way of mounting is anodic bonding which operates in a much more convenient manner than the former does. It appears as a very promising approach to the FED manufacturing. In this thesis the mounting process ,based on anodic bonding ,of spacers on ITO glass will be developed to facilitate the bonding process ,with an aim at carrying out anodic bonding at some specific low voltage and low temperature.
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Tai, Jung-Chi. "Magnetic Tunnel Junction with Organic Spacer." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-1607200718530300.
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Kao, Wei-Che, and 高偉哲. "Automatic Detection System for LCD Panel Spacer." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/p6w47a.
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碩士國立臺灣科技大學
電子工程系
99
After thirty years of liquid crystal display (LCD) development, the applications of LCDs have grown quickly and have wide application. LCD has the following features: thin, lightweight, low power, less EM radioactive, compatible with semiconductor processing technology. During the manufacturing process of liquid crystal display panel, manufacturers have to inject liquid crystal between the front and rear pieces of glass after injecting spacer which is used to maintain the cell gap (the distance) between the front and rear pieces of glass. It will cause the blurred image displayed on the LCD if the thickness between two glass plates is not equal. Usually the detection of spacer is manually to count the number of spacer and check the overlapped problem of spacers through a microscope. To solve this issue with automatic machine vision, an image processing technology is developed in this thesis. In our system, we capture images from an industrial microscope-capability camera, and then a detection processing algorithm is used to process the images to determine if the image is a focused one. Our method greatly improve the efficiency and accuracy. In our system, we integrate an auto-focus with the LCD panel spacer’s count and detection. There are three main steps: 1) Capture clear images by using an auto-focus algorithm. 2) Count the number of spacer and detect if they are overlapped or not by applying region histogram equalization, binarization, and connected component image processing algorithms. Experiment show that the error rate is under 1%. 3)Use wxWidget GUI to display the result (the output from step 2) on the monitor. Moreover, we use OLE to save the result in an Excel file for further processing and archiving purpose.
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CHEN, KUO-PING, and 陳國平. "Optimization of Color Filter Photo Spacer Process." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/48aukc.
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碩士明新科技大學
工業工程與管理系碩士在職專班
105
With the continuous development of photovoltaic panel industry, TFT-LCD technology has become the mainstream of the domestic production of the panel, however, fierce competition panel makers for sustainable development of the company, in addition to actively utilize small panel plant and turn into more profitable and more changes outside of niche product development, strengthen quality control and accuracy improvement, it is to reduce costs and increase profits only way. Quality characteristics in the TFT-LCD industry interval of the color filter photosensitive material PS (Photo Spacer) process in which high average column Photo Spacer Although there is permeable and the average height of the machine parameters characteristic of the considerable experience of the process adjustment specifications center close, but still has a high uniformity column from the whole problem of excessive, resulting in abnormal posterior segment CELL quality manufacturing process. In this thesis, we focus on the case of the company used for the earlier generation of small and medium-sized color filter plant equipment, functional constraints in the equipment and without additional cost transformation costs, change part of the design and parameters, and finally through Taguchi method and Response surface method validation and analysis The best combination of parameters to solve the Photo-Spacer process quality characteristics of the column uniformity of the problem, the experimental results show that the PS full-range greatly improved from 0.3um greatly reduced to 0.07um, in addition to achieving improved process accuracy and improve yield, but also do For later evaluation of the design reference, but also to provide greater after the CELL process LC margin.
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Wu, Cheng-Yi, and 吳正一. "Sidewall Spacer Etch Improvement in VLSI Process." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/27425539565450669494.
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碩士國立交通大學
工學院碩士在職專班半導體材料與製程設備組
97
A procedure based on Taguchi methods and integrates more sensitivity EPD to develop a new etch recipe, and provide an electrical measurement method for monitoring the sidewall spacer width. The sidewall spacer has been used extensively in conventional CMOS processing, leading LDD (lightly-doped drain) formation to less hot carrier degradation allowing self alignment to prevent S/D short in the salicide process. In this thesis, we figures out by optimizing etch parameter with low pressure and Ar flow can be improved etch uniformity effectively. Creating a fast and correct measurement process for every die SW width to improve device performance is an important topic. In this thesis, we successfully derivate an equation to predict SW width from resistor measurement.
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Fwu, Tseh-Chung, and 符策忠. "An analytic investigation of the spacer grids configuration." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/24623249586307621688.
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Kuo-ChuanWu and 吳國川. "Optimization of LCD Color Filter Photo Spacer Process." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/06328666868071706353.
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碩士國立成功大學
工程科學系碩博士班
98
For the past years, the government has been exerting great efforts to set the “Two Trillion Twin Stars” industry development into action; in 2006, the Optoelectronics Industry has reached an output value scope of NT$220,000,000,000.00 in total. The future local industries are exerting all efforts in research and manufacturing, to cooperate with the government’s established strategy in order to achieve the deserved target;in the optoelectronics panel TFT-LCD industry, each panel manufacturers are active on the manufacturing technology, vertical integration, quality control, expansion and production increase,, to achieve lower capital, greater profit and larger competition advantage. This paper aims to improvement on quality characteristic of Color Filter manufacturing process, the PS (Photo Spacer) process to perform analysis and research. The Taguchi Method by ANOVA and Orthogonal array was used perform the experiment, to find the key factor, standard level, most ideal parameter group and adjustment factor to overcome Photo Spacer process variation of quality characteristic in order to decreasing out of specification production , and increasing the manufacturing capability and efficiency. With the application of the above-mentioned ideal parameters on the production line for testing and verification, the original process capability of PS Top C.D. Cp=1.19,Cpk=0.43 .Then, after using the adjustment factor, the process capability of PS Top C.D. has reached Cp=2.01,Cpk=1.81, Bottom C.D. before improvement : Cp=1.12,Cpk=0.98,after improvement : Cp=1.37，Cpk=1.31, PS Hm before improvement : Cp=1.02,Cpk=0.47,after improvement : Cp=1.02，Cpk=0.98.
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Yen, Wen-Tsai, and 嚴文材. "Anodic Bonding for Felid Emission Display Spacer Study." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/50151157488252012752.
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碩士國立彰化師範大學
機電工程學系
93
The study the utilize of anodic bonding method, aims sputtering the glass substrate plate with treated differently, the Soda lime glass with sputtering and the Al/Cr/ITO glass to proceed on the assessment of bonding strength; by adjusting medium the film thickness, bonding temperature and bonding voltage, In order to discuss different influence on the bonding strength of whole the spacer of Al/Cr thin film characteristic .In the experiment, utilize of to Atomic Force Microscope to analysis Al/Cr surface shape thin film, the bonding area observation is estimated using an optical microscope to match the image and the software to observe, the element dispersal inside the bonding interface is analyzed using an energy dispersive spectrometer, bonding strength utilize shear stress to destroy the experiment to test, the broken section makes use of scanning electron microscope to observe . Via the experimental result, higher temperature , voltage and proper film of are thickness can all get the higher largest electric current value, electric charge amount, the rate of area and the bonding strength. In addition, via the interface analyse that learns, main controlling mechanism that the bond key forms may be O- ion, the reciprocation to Al , Cr metal atom has something relevant, and Sn, In metal atom have nothing relevant. Match the spacer device bonding where the wet etching and made to put, Succeed in applying to Field Emission Display the feasibility of the completion to bond spacer experiment actually .The best parameter is：300nm film thickness, bonding temperature of 300℃,and bonding voltage of 700V,respectively. Keyword：Anodic bonding、Sputtering、Field Emission Display、Spacer
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Chen, Jue Jye, and 陳志傑. "Study of Poly-Si Spacer for VLSI Circuits." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/65113894076454146540.
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碩士國立交通大學
電子研究所
81
At first ,different materials, including low pressure chemical vapor deposition (LPCVD) TEOS ,LP Si3N4 , plasma enhanced CVD (PECVD) oxide ,LPCVD borophosphosilicate glass (BPSG) and LPCVD Poly-Si ,have been systematically fabricated and the spacers for the VLSI circuits.The electrical properties shows that the Poly-Si is the best one of all the these spacers due to its highest dielectric constant ,K=11.9 , This result is consistent with the literatures.Although Si3N4 has the higher dielectric constant ,it encounters the stress problems so that it is not suitable for the practical application. BPSG and PE oxide are also excluded due to their impurity contents. Hence the remained two candidates ,TEOS and Poly-Si ,are further appraised in the second section of this study. The purpose of the second section is focused on the TEOS and Poly-Si spacers. By using TEOS and Poly-Si as the spacers with different over etching (O/E) times ,lightly doped drain (LDD) structures can be fabricated via the direct implantation of arsenic and boron ions through these spacers. Then ,this simplified LDD technology is evaluated to subsitute the conventional LDD process. Fortunely ,Poly-Si spacers with the O/E times of 50 sec and 60 sec can meet the requirement of hot carrier immunity comparable to that of the conventional N-MOS LDD devices. However ,too long O/E time of the Poly-Si spacers results in the deep penetration of the boron and cause the sub-micron P- MOS punch through after the high-temperature annealing at 950 C. Consequently ,the sub-micron PMOS with this Poly-Si spacer will exhibit the normal-on characterics.
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Yung-An, Wang. "Implementation of Class-Based ACK Spacer in Linux Platforms." 2005. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2007200502140700.
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Kang, Chih-Kai, and 康智凱. "Study of Tungsten-Spacer Polycrystalline Silicon Thin Film Transistors." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/33241351040728515702.
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碩士國立中山大學
物理學系研究所
90
In this thesis, we successfully fabricated GOLD ( gate-overlapped LDD ) polycrystalline silicon thin-film transistors ( poly-Si TFTs ) with selectively deposited W spacers. Under appropriate deposition conditions, tungsten ( W ) films can be selectively deposited on poly-Si gate electrodes to form spacers without any additional etching process. Compared with the conventional poly-TFTs without LDD structures, our devices effectively lower the leakage current and sustain a comparable on current. The transconductance of our devices is compatible to that of conventional devices, because W-spacer acts as a part of gate electrode to induce channel when the device is operated under ON state. To further study the characteristics of W-spacer TFTs, devices with different channel thickness, spacer thickness and LDD dopant density are fabricated. It is found that thinner channel, thicker spacer and lightly doped LDD implant can effectively suppress the floating body effect and also the kink effect. By comparing device performances after plasma passivation, it is also found that small-dimensional devices have better passivation effect. Finally, the hot-carrier reliability of W-spacer TFTs is also studied. Due to the reduced electric filed on the drain side, W-spacer TFTs have better reliability than the conventional counterparts.
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Wang, Yung-An, and 王永安. "Implementation of Class-Based ACK Spacer in Linux Platforms." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/53414980025708404011.
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碩士國立臺灣大學
電信工程學研究所
93
In this thesis,we propose a novel architecture of the Class-Based ACK Spacer and implement it on Linux platforms. This ACK spacer could be installed on the server side, client side, or on the router to provide different priorities and bandwidth allocations of each TCP class and session over ACK packet control. Since ACK is relatively small compared to TCP data packet, we hypothesize that ACK is better for buffering or in CPU load. We use static priority algorithm and token bucket to solve multi-class scheduling problem. To control the sessions in the same priority class, we propose two session scheduling algorithms, Token Round Robin and Frequency-Based Rotation Priority Queue, to achieve fairness between sessions. Finally, we construct experiment environment to verify our implementations. The TCP throughput could be stabilized and improved with proper parameters set. Bandwidth fair-share could be achieved. At last, we also analyze CPU load using different scheduling algorithms.
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Po, Tsai Cheng, and 蔡政博. "Synthesis and Characterization of New Ferrocenylfluorene with Alkynyl Spacer." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/22650247206147868455.
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碩士中國文化大學
應用化學研究所
88
Starting up with Ferrocene,we,step-by-step,syntgesize Chloromerc-urigerrocene,Iodoferrocene, (Teimeghylsilyl)ethynlgerrocene andalkyne-contained Ethynylgerrocene.Further taking alkyne beidge and Fluirene as the Ligand and taking Sonogashira coupling with applied metal,Pd(II),CuI,catalytic,action to synthesize,2,7-ethynylferrocene-9,9-diRlfluorene,2-ethynyferrocene-7-brono-9,9-diR1fluorene,2-ethyny1ferrocene-7-nitro-9,9-diR1fluorene,2-ethynylferrocene-7-R-9,9-fluorenylferrocene and such ethynylferrocenylfluorenes compounds of organicmetals. The new ethynylferrocenylfluorenes are illustrated below, in sixteen new products.Amomg them,when R is in ethynylferrocene,R1 can be three sorts of new products of H, Me, Et.When R is Br, R1 can be three new products of H, Me, Et. When R is NO2 and H, R1 remains to be H, Me, Et to obtain three new products. As to 2-ethynlferrocene-7 R-9,9-fluorenylferrocene, we take R as H or ethynylferrocene to obtain two new products each as well. In R of the new ethynylferrocenylflyorenes compounds,we can take anyfitting ligand to fit, e.g.,benezen and thiophene to insert to syntheside organicmetallic secondary non-linear optical materials,or using fluorene is biphenyl to be used for electromic conduction or synthetic polymer.In the future,this might be used for optical materials and sensor.This stands for the orientations and prospects of our future research.
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Wang, Shiou-Wen, and 王秀文. "Internal Transcribed Spacer and Quick Identification of Botrytis elliptica." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/42637919705770998864.
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碩士國立臺灣大學
植物病理學研究所
88
Botrytis spp. includes important plant pathogenic fungi which cause gray mold or leaf blight disease on several plants. Botrytis elliptica causes Botrytis blight on leaves and flowers of lily plants. B. gladiolorum mainly infects on gladiolus plants. The host range of B. cinerea includes plants of over 100 different species. In this study, the pathogenicity assay showed that all three Botrytis spp. could infect lily petal without wounding, but only B. elliptica could infect lily leaves without wounding. B. cinerea could only infect the wounding sites of lily leaves. B. gladiolorum could not infect lily leaves even with wounding. For the purpose of quick differentiation of B. elliptica, B. cinerea, and B. gladiolorum, PCR techniques was used to establish a rapid and sensitive procedure of detection. Primers are designed according to the sequence of ITS1 and ITS2 regions of Botrytis spp. Among four primer pairs, primer pair 102/106 (primer 102 designed from ITS1 of B. gladiolorum) could amplify a DNA fragment of predicted size from B. gladiolorum, but not from B. elliptica and B. cinerea. Primer pair 102-1/103 (primer 103 designed from ITS2 of B. elliptica and B. cinerea) could amplify a DNA fragment of predicted size from both of B. elliptica and B. cinerea, but not from B. gladiolorum. Both primer pairs could not amplify expected DNA fragments from Sclerotinia sclerotiorum. Primer pair 102-1/103-2 could amplify a DNA fragment of predicted size from Botrytis gladiolorum, but still obtained weak signal from B. elliptica, and B. cinerea. Primer pair 102-1/106 (designed from ITS conserved region of Botrytis spp.) could amplify DNA fragment of predicted size from B. elliptica, B. cinerea, and B. gladiolorum, and also from Sclerotinia sclerotiorum. All of four primer pairs could not generate detection signal from other pathogenic fungi of nine species and lily. Restriction map of ITS1-5.8S rDNA-ITS2 region of B. elliptica, B. cinerea, and B. gladiolorum were analyzed. PleI-digested DNA pattern of B. gladiolorum was different from that of B. eliptica and B. cinerea.
48
Li, Yu-Ling, and 李雨霖. "Microhydrodynamic Analyses of Transport Phenomena in Spacer-filledMembrane Module." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/35164137151653049365.
Full textAbstract:
博士中原大學
化學工程研究所
95
Effect of spacer design on fluid flow and separation efficiency in a spacer-filled channel was conducted using computational fluid dynamic (CFD) and experimental techniques. The spacer serves both as mechanical stabilizer for channel geometry and turbulence promoters for reducing polarization phenomena near the membrane surface. Previously, several factors affect the pressure drop and mass transfer in a spacer-filled spiral-wound module have been studied based upon flat channel module. However, the curvature of the spacer varies along the spiral flow path. No any effort has been placed on the effects of curvature of the spacer in the spiral-wound modules on the pressure drop, shear stress and filtrate rate through the curved module. Purposes of this study were emphasized on the effects of curvature of the spacer-filled channel, filament arrangement, feed velocity and membrane resistance in the spiral-wound modules on the pressure drop, shear stress and particles deposition through the modules by CFD, experimental equipment and direct observation through the membrane. Results showed that increase of the curvature of the spacer-filled channel will result in increases the shear stress ratio and variations in inner and outer filtrate. On the other hand, the spacer-filled curved channel in a spiral wound module causes unequal shear stress at inner and outer membrane surfaces. Such unequal shear stress at the inner and outer surfaces would be expected to have an adverse impact on the membrane module performance because of different fouling characteristics for adjacent membrane leaves. Results showed that decreasing of the diameter of outer filament and increasing of the diameter of inner filament can improve this adverse impact. Furthermore, particle deposition in spacer-filled membrane modules is investigated using a computational fluid dynamic (CFD) technique. The flow field and particle transport in the channels with permeable membrane surfaces are calculated using the commercial available CFD software FLUENT®. A scheme similar to the Eulerian–Lagrangian numerical method is adopted for the two-phase flow simulation. Particle transport in spacer-filled channel is analyzed by considering fluid drag, body force, lift force and interaction forces exerted on the colloids. Feed velocity, permeation flux, and spacer arrangement effects on particle deposition are discussed comprehensively. Based on conclusive preliminary study results, multi-phase flow simulation can provide microscopic understanding of the fouling mechanism in the spacer-filled channel and prove to be a powerful tool to aid in membrane module design. Finally, a platform was constructed based on multi-phase CFD approach and experimental techniques for fundamental study of membrane module design.
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Chin-WenChien and 簡慶聞. "Improvement on CpK of Color Filter Photo Spacer Process." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/60919818135213518857.
Full textAbstract:
碩士國立成功大學
工程科學系碩士在職專班
104
Since the 1990s, Taiwan began to develop panel industry, which has been the focus of technology industries. In the beginning of the TFT-LCD development, the global TFT-LCD panel demand was mainly supplied by Taiwan, Japan and South Korea panel makers. Afterwards, all the panel makers aggressively expanded their production capacity, leading to the excess output of each panel size. Due to the consequent price competition, the more each panel factory produces, the severer the factory loses. This results in the elimination of many panel makers in the industry. Japanese panel factories are the good examples of the elimination phenomenon. Counting on the excellent technology and ability, Japanese thought that the quality is equal to the order. Compared with other countries, the more expensive labor cost is the primary reason for the collapse of Japanese Companies. Consequently, Japan has been gradually withdrawn from the panel production. In view of this condition, the large panel makers stop expanding the production capacity. The products of relatively good quality and specification and high average unit price are the new developing goal, to obtain high profits and thus to have a good competitive edge. The thesis is to study the optimization of production quality for the PS (Photo Spacer) manufacturing process of TFT-LCD semi-finished product, color filter (CF). Under the current configuration of the existing production machines, it is expected to achieve the enhancement of process capability index with the minimum cost, to reduce the adjusting time of unnecessary machine parameters and to increase the number of output products by using the Taguchi method.
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Hung, Chia-lung, and 洪嘉隆. "The study of Photo-Spacer application to STN-LCD Display." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/a644np.
Full textAbstract:
碩士國立中山大學
光電工程研究所
96
Currently , the STN-LCD with twist angle of 240 degree is the most popular operation mode . In this thesis , we utilize Photo-Sensitive spacer of TFT-LCD to substitute for the traditional spacer , and apply them in the above mentioned STN-LCD . The traditional spacer were used N2 air to spray on glass substrate by SUS tube . It make light leakage , decrease the transmittance , contrast ratio and aggregate spacer easily . When we pressure on glass and the phenomenon of migration has been found accordingly . It will influence quality of LCD . So we utilize Photo-Sensitive spacer to substitute for the traditional spacer in order to improve the defect . In this thesis , we fabricate different kind Photo-Sensitive spacer of size , shape and area ratio (Photo-Resist (NPS) from Everlight Chemical Industrial Corp) . We utilize Photo Lithography process to form the spacer thickness on insulation layer , and find the best type . In this experiment , the different characteristic of material between traditional spacer and Photo-Spacer were compared . And we utilize different process condition (pressure) and material(LC Δnd) to discuss the relation . Finally , we proof the advantage of Photo-Spacer apply in STN-LCD .