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The political dynamics of growth and structural transformation in Kenya : exploring the role of state-business relationsTyce, Matthew January 2018 (has links)
Moving beyond a focus on institutional frameworks to the deeper forms of politics and power relations that determine their functioning, this thesis explores the political dynamics of growth and structural transformation in Kenya. Deploying a conceptual framework that combines political settlement analysis, which explores how the underlying structure of power shapes incentives for elites to adopt developmental forms of governance, with two concepts from the state business relations literature, the deals and rents spaces, which together link macro level political settlement analysis with a meso level analysis of specific economic actors, the thesis offers new understandings for Kenyas economic development. It argues that Kenyas period of comparatively good growth during the 1960s and 1970s, generally attributed to the inheritance of reasonably coherent institutions at independence as well as favourable external dynamics, actually owed more to Kenyas relatively stable political settlement, which allowed ruling elites to unveil a closed ordered deals regime that provided favoured investors, predominantly from President Kenyattas Kikuyu ethnic group, but also foreign firms, with sufficient credible commitment to invest in productive activities. Similarly, the thesis finds that Kenyas declining performance during the 1980s and 1990s, explained in the literature by worsening external conditions and the capture of increasingly outdated colonial era institutions, was driven more by the ruling coalitions increasing vulnerability, which incentivised then President Moi to prioritise short term politics of survival over sound economic management, particularly after the transition to multi party politics in the 1990s. This resulted in an extremely closed and increasingly disordered deals space, undermining investor confidence and growth. However, a key finding of the thesis, and one that challenges a general view within the literature that corruption permeated all areas of Kenyas economy during the 1980s and 1990s, is that key sectors like horticulture and garments, which made vital contributions to foreign exchange and vote winning employment, were relatively insulated from these political dynamics, helping to explain why Kenya did not suffer a complete growth collapse. Finally, the thesis finds that improved economic outcomes from the early 2000s did not flow from the enactment of donor demanded reforms, as the literature suggests, but rather from increased order within the deals space. This was driven by a reduction in the ruling coalitions vulnerability as well as the ideological predilections of President Kibaki, Mois successor, whose deeply held ideas drove him to implement his economic vision in the face of countervailing political incentives. Critically, the thesis finds that Kibaki enforced ordered but closed deals in Kenyas financial services industry, giving influential banking and telecommunication firms the regulatory space and certainty that they required to innovate with products like mobile money, kickstarting a financial services revolution that has, amongst other things, significantly improved the availability and costs of credit. However, a key finding is that the closed deals predominant in banking and telecommunications, combined with the open deals found in export focused sectors like horticulture and garments, where firms have utilised their increased holding power to push for further openings in deals, has led to the emergence of a dualistic deals space that, if not tackled through incremental governance reforms, undermines the prospects for Kenya achieving a long term growth acceleration and structurally transforming its economy. These findings inform the thesis policy recommendations, which include a focus on how pockets of effectiveness can play a critical role in promoting growth in otherwise unfavourable governance contexts.
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Parasitismo em Cnemidophorus ocellifer (Squamata:Teiidae) de quatro ecossistemas do nordeste brasileiroEloi, Felipe Jardelino 30 April 2013 (has links)
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Previous issue date: 2013-04-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Parasite is an organism that lives inside (endo) or in surface (ectoparasites) from
another organism, the host, feeding, showing some degree of adaptation and causing some
damage to it. In Brazil one of the most commonly found lizard is the Cnemidophorus
ocellifer, active forager, with wide national distribution except Amazon, and diurnal
heliotherms, which mainly inhabits open areas. Therefore, this study aims to characterize the
patterns of infestation by parasites in populations of C. ocellifer in four ecoregions of
northeastern Brazil, the abundance, composition, diversity and body distribution. We
examined 399 specimens of C. ocellifer. Eutrombicula alfreddugesi was the only ectoparasite
species found in all populations studied. The Sete Cidades population was the most
parasitized with 9,819 mites found, and the population of Barra Cunhaú was less parasitized,
with only 445 individuals and 66 mites free from ectoparasites. We found six types of
endoparasites: Platyhelminths Cestoda (n=49) and Nemathelminths Pharyngodon sp.
(n=1633) in stomachs and intestines, Nemathelminths Piratuba sp. (n=6), Oswaldofilaria sp.
(n=17) and Physaloptera spp. (n=1), only in coelomic cavities in Sete Cidades, and
Pentastomid Raillietiella mottae (n=5) in the lungs only in Barra do Cunhaú. For ectoparasites
males are significantly more infested than females and this is probably linked to the inverse
relationship that exists between testosterone levels in the blood and immune system
efficiency. The sites of infestation were instrumental in the infestation by ectoparasites in all
populations studied, indicating mainly post-inguinal regions as significantly more infested
sites in all populations. These results are not only related to the presence of dermal folds in
these regions, since there are folds in other parts of the body of these lizards and they showed
no such significant results. The infestation was also partially influenced by the environment,
but it may be that this is influenced by secondary factors and not necessarily environmental.
Body condition, another fitness parameter, was also partially influenced by parasitic
infestation, but not as expected, where most infected individuals have better body condition,
refuting the hypothesis (individuals with greater intensity would be less parasitic body
condition score). An overview of all these results suggests that the infestation by ectoparasites
can be associated with characteristics of fitness and sexual selection, corroborating the
Handicap Theory. If not this way, a parasite can present with its host, a neutral relationship
(comensal) or even positive, even at low level (mutual). Endoparasites may be acting
illegitimate way, without the hosts in no way benefit from this interaction, but can at least
present a pattern of species diversity known for other taxa. / Parasita é um organismo que vive dentro (endoparasitas) ou na superfície
(ectoparasitas) de outro organismo, o hospedeiro, se alimentando, apresentando certo grau de
adaptação e causando algum dano ao mesmo. No Brasil um dos lagartos mais comumente
encontradas é Cnemidophorus ocellifer, forrageador ativo, de ampla distribuição nacional
exceto Amazônia, heliófilo e diurno, que habita principalmente áreas abertas. Sendo assim, o
presente estudo tem como objetivo caracterizar e testar hipóteses sobre os padrões de
infestação por parasitas em populações de C. ocellifer de quatro ecorregiões do Nordeste
Brasileiro, quanto à abundância, composição, diversidade e distribuição corporal, bem como
sobre os efeitos da intensidade parasitária sobre a aptidão dos hospedeiros. Foram examinados
399 exemplares de C. ocellifer de quatro populações: Barra do Cunhaú/RN, Cabaceiras/PB,
PARNA Sete Cidades/PI e REBIO Guaribas/PB. Eutrombicula alfreddugesi foi a única
espécie de ectoparasita encontrada em todas as populações estudadas. A população de Sete
Cidades/PI foi a mais parasitada, com 9.819 ácaros encontrados, e a população de Barra do
Cunhaú/RN foi a menos parasitada, com apenas 445 ácaros e 66 indivíduos livres de
ectoparasitas. Foram encontrados seis tipos de endoparasitas: Platelmintos Cestoda (n=49) e
Nematelmintos Pharyngodon sp. (n=1.633), em estômagos e intestinos; Nematelmintos
Piratuba sp. (n=6), Oswaldofilaria sp. (n=17) e Physaloptera sp. (n=1), em cavidades
celomáticas (apenas em Sete Cidades); e o Pentastomídeo Raillietiella mottae (n=5) nos
pulmões dos indivíduos de Barra do Cunhaú. Para ectoparasitas os machos são
significativamente mais infestados que fêmeas e isso provavelmente está ligado à relação
inversamente proporcional que existe entre as taxas de testosterona no sangue e a eficiência
do sistema imune. Os sítios de infestação foram determinantes para a infestação por
ectoparasitas em todas as populações estudadas, indicando principalmente as regiões pósinguinais
como os sítios significativamente mais infestado em todas as populações. Esses
resultados não estão relacionados apenas a presença de dobras dérmicas nessas regiões, já que
existem dobras em outras partes do corpo desses lagartos e elas não apresentaram,
significativamente, altas infestações. A infestação também foi parcialmente influenciada pelo
ambiente, mas pode ser que essa influência seja por fatores secundários e não necessariamente
ambientais. A condição corporal, outro parâmetro de aptidão, também foi parcialmente
influenciada pela infestação parasitária, mas não como esperado, onde indivíduos mais
parasitados apresentaram melhor condição corporal, refutando a hipótese mencionada na
introdução (indivíduos com maior intensidade parasitária teriam menor índice de condição
corporal). Um apanhado geral de todos esses resultados sugere que a infestação por
ectoparasitas pode estar associada a características de aptidão e seleção sexual, corroborando
a Teoria da Desvantagem. Se não dessa forma, um parasita pode apresentar, com seu
hospedeiro, uma relação neutra (comensalista) ou até mesmo positiva, mesmo que em baixo
nível (mutualista). Os endoparasitas podem estar atuando de forma espúria, sem que os
hospedeiros em nada se beneficiem com essa interação, mas podem ao menos apresentar um
padrão de diversidade de espécies conhecido para outros táxons.
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À côté des objets. Leur présence et visibilité a l’écran / At the side of objectsMerlo, Alessandra 16 December 2010 (has links)
Le thème de cette thèse est le questionnement autour des objets cinématographiques. Par le terme « objet » on entend ici toute chose manipulable, tout outil ou objet décoratif qui se situe dans la scène filmique et à l’intérieur du cadre. On a choisi le terme « objet » - au lieu de « chose » - pour son caractère d’opposition étymologique et conceptuelle au « sujet ». L’objet en question – au-delà de las séparations entre l’accessoire et le décoratif, entre fonctionnel et contextuel – est donc présent, mais sa visibilité varie selon le cadrage, la mise au point, les relations de compositions, la vraisemblance. Mais elle dépend aussi des prédispositions du spectateur. Par conséquent, à partir d’une définition et d’une première étude des ses caractéristiques physiques [de position, de gosseur, de mouvement et de relation], le travail aborde la question de comment, quand et pourquoi l’objet se montre [et le spectateur le perçoit]. D’un point de vue méthodologique, le travail enrichit chaque cas par un exemple analysé et illustré à partir d’un répertoire iconographique. Cependant, au moment d’exposer et développer un système d’objets cinématographiques, l’analyse a été conduite sur un seul film, I pugni in tasca, de Marco Bellocchio [1965] : ce qui nous intéressait ici c’était la possibilité d’arriver à établir – dans le cas particulier – le fonctionnement systématique des objets. / The present thesis examines cinematographic objects. It is here understood by the term “object” anything that is able of being manipulated, each utensil or decorative apparel that is placed in the filmic scene and inside its frame. The decision of using the term “object” - instead of “thing”- was taken because of its conceptual and etymological opposition to the term “subject”. Hence, the object under inquiry –trying to go further than the mere distinctions between accessories and decoration, functional and contextual- is present; its visibility varies depending on the chosen scene, its composition, focalization and veracity. Moreover, its visibility also depends on the spectator’s dispositions. Therefore, departing from a definition and an initial study of its physical characteristics [position, size, movements and relations], this thesis addresses the questions about how, when and why the object is shown [and the spectator perceives and sees it]. From a methodological standpoint, the present thesis enriches each one of its study cases with the analysis of an example, which is illustrated from an iconographic repertoire. Nonetheless, at the moment of presenting and developing a system of cinematographic objects, the analysis focuses itself on a single film: I pugni in tasca, by Marco Bellocchio [1965]. This is done with the aim of establishing –for a particular case- the systemic workings of objects.
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NUMERICAL SIMULATION OF PRESSURE WAVE SUPERCHARGER WITH POCKETS OPERATING AT DIFFERENT SPEEDSPawan Jaysing Sutar (9750260) 08 June 2021 (has links)
<div>Pressure wave supercharger is an application of wave rotor technology that utilizes compression waves produced by high-pressure engine exhaust gas to compress the fresh intake air within the channels. The phenomena within the wave rotor channels are governed by compression and expansion waves initiated when the channel ends are periodically exposed to differing pressure ports. Two incoming fluids are brought into contact for a very short amount of time to facilitate efficient energy and momentum transfer, thereby exchanging pressure dynamically between the fluids by means of unsteady pressure waves. Since the energy transfer is based on unsteady pressure waves, correct matching of waves and ports is essential for optimum results. Mistiming of the waves in the channels is detrimental to the efficient exchange of pressure and low-pressure exhaust scavenging, which ensures minimum exhaust gas recirculation. Due to varying speed and load conditions of the unit to be supercharged, it is not always possible to maintain the rotor speed constant at the design point.</div><div>To mitigate the effects of wave mistiming due to varying speed, a well-designed combination of wall-pockets was used in Comprex® pressure wave supercharger. The wall-pockets are the recesses provided in the endplates of pressure wave superchargers to create necessary pressure zones at desired locations. This thesis details an extensive qualitative and computational investigation of the performance of pressure wave superchargers with pockets. Numerical simulations of pressure wave superchargers have been performed using the wave rotor analysis codes employed at the Combustion and Propulsion Research Laboratory at IUPUI. This work also pays close attention to inspecting the numerical schemes and modeling of different physical phenomena used in each code. A comparative verification of the wave rotor analysis codes has been conducted to ensure that the same fundamental numerical scheme is correctly implemented in each code. The issue of low-pressure scavenging has been demonstrated by simulating the four-port (pocketless) pressure wave supercharger operating at lower speeds. The wall-pockets have been modeled using a simple lumped volume technique. The gas state in the lumped volume of pockets is estimated using the continuity and energy equations such that the net mass and energy fluxes between each pocket and the wave rotor channels are close to zero. The lumped volume models of pockets have been implemented in the four-port wave rotor configurations to simulate the pressure wave superchargers with pockets. The simulation results show that the pockets assist to maintain sufficient pressure in the desired zones to facilitate proper low-pressure scavenging during lower rotor speed operations. The Comprex simulation results have been observed to be in good agreement with experimental data and qualitative analysis. Specific observations on the performance of each code and comprehensive simulation results have been presented.</div>
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Apport de la modélisation et des simulations de dynamique moléculaire à la description de STAT5 comme cible pour moduler la signalisation oncogénique / Contribution of molecular modeling and dynamics simulations to describe STAT5 as a target to modulate oncogenic signalingLangenfeld, Florent 05 June 2015 (has links)
STAT5 est une protéine de la signalisation cellulaire normale, qui peut jouer un rôle important dans la transformation, la survie et à la résistance aux inhibiteurs de tyrosine kinase des cellules tumorales. Son activation constitutive par phosphorylation est liée à la présence de protéines oncogéniques comme la protéine de fusion BCR/ABL1 (leucémie myéloïde chronique) ou de formes mutées de KIT (mastocytoses), par exemple. L’inhibition pharmacologique de STAT5 constitue donc un enjeu thérapeutique majeur pour plusieurs pathologies malignes. Nous avons réalisé la première modélisation et les simulations de dynamique moléculaire des principales formes de STAT5 : la forme monomérique cytoplasmique phosphorylée ou non, et la forme dimérique phosphorylée et liée à l’ADN. Nous avons caractérisé les propriétés dynamiques et le réseau allostérique intramoléculaire des monomères de STAT5. Les résultats générés montrent des variations structurales et dynamiques liées à la différence de séquence primaire des isoformes de STAT5 et/ou à la présence du groupement phosphate. Deux poches à la surface des protéines ont également été caractérisées. Leur localisation à proximité de voies de communication allostériques suggère que ces poches pourraient constituer des sites de modulation des fonctions de STAT5. Nous avons également caractérisé les liaisons hydrogènes entre les monomères constituant les dimères de STAT5 et leur reconnaissance de l’ADN. En outre, nous avons identifié des résidus clés aux interfaces entre les entités moléculaires, nous permettant de mieux comprendre les effets de mutations de STAT5 observées en clinique dans certaines pathologies malignes. / STAT5 is a protein involved in normal cell signalling that is crucial for transformation, survival and resistance to tyrosine kinase inhibitors of tumour cells. The constitutive phosphorylation activates STAT5 and is related to oncogenic proteins like the hybrid protein BCR/ABL1 (chronic myeloid leukaemia) or mutated KIT receptor (mastocytosis). The pharmacologic inhibition of STAT5 is thus a major therapeutic concern in several malignant pathologies. We performed the first modelling and molecular dynamics simulations of the main cellular species of STAT5: the cytoplasmic phosphorylated or unphosphorylated monomer, and the phosphorylated dimer bound to DNA. We characterized the dynamical properties and the intramolecular allosteric network of the monomers. The generated results show structural and dynamic variations linked to the primary sequence changes between the two STAT5 isoforms and/or to the phosphate group. Two pockets were characterized at the surface of STAT5. Their location at close proximity of allosteric communication pathways suggests new putative inhibition sites to modulate STAT5 functions. We also described the hydrogen bonds network between the monomers of the dimeric species and the recognition of the DNA. We identified key residues at the interfaces, allowing us to better understand the effects of clinically relevant STAT5 mutations observed in malignancies.
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Jazykové prostředky vyjadřující dativ / Forms of Expressing Dativ in Czech and JapaneseJandejsková, Viola January 2013 (has links)
This thesis disserts on problem of translation of dative relations in Karel Čapek's "Tales from two pockets" into Japanese. Goal of the thesis is to identify and describe means of expression of dative in Japanese translation and figure out if there are any differences in interpretaion and expressing dative in Czech and Japanese and what they are. Using method of excerption of example sentences and comparation of original with translated version, I organised the example sentences into six categories according to linguistic means of expressing equivalent of Czech dative used in Japanese translation. In these six categories, there are included both grammatical and semanthic expressions and idioms and phrases. The result is the detection of the main difference in degree of necessity to express a dative subject explicitly. There is a strong tendency of Japanese to implicit expression of dativ subject by means of special expressions of personal orientation, semanthics of predicate or context.
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Évaluation des performances chromatographiques de phases stationnaires amphiphiles à base de dérivés de l’acide choliqueDionne-Dumont, Vincent 10 1900 (has links)
Au cours des dix dernières années, des composés oligomères intéressants à base de
l’acide cholique ont été synthétisés et caractérisés par nos collaborateurs du groupe de Julian
X.X. Zhu à l’Université de Montréal (UdeM). Dans un travail récent, ils ont synthétisé un dimère
d'acide cholique qui pouvait former de façon réversible une cavité moléculaire lorsqu'il était
dissous dans des milieux de polarité différente ; dans l'eau, le dimère forme une cavité
hydrophobe, et dans des milieux organiques, le dimère forme une cavité hydrophile. Ainsi, ce
type de composés amphiphiles, lorsqu'ils sont en solution, démontre un comportement de cavité
moléculaire qui dépend des conditions du solvant, formant une cavité de polarité opposée à celle
du milieu dans lequel ils se trouvent. Le comportement d'inversion de la cavité résulte de la
flexibilité conformationnelle du lieur chimique entre les monomères d'acide cholique. La
capacité des cavités de piéger des sondes moléculaires en fonction de leur polarité suggère que
ce type d’oligomères d’acide cholique pourrait constituer des phases stationnaires intéressantes
pour la chromatographie en phase liquide à haute performance (HPLC), où la séparation est
basée sur la polarité du soluté par rapport à la phase mobile. Puisqu’ils peuvent constituer des
cavités hydrophobes et hydrophiles, ils pourraient donc être exploités en chromatographie en
phase normale (NPC) et en chromatographie en phase inverse (RPC). La possibilité d'avoir une
phase stationnaire réversible avec une affinité bimodale appropriée pourrait être avantageuse en
biosciences, en sciences de l'environnement et favoriser la séparation de mélanges complexes
en élargissant le champ d'application d’une seule colonne chromatographique. L’affinité
bimodale pourrait notamment permettre d'éviter de changer le mode de fonctionnement du
HPLC; un processus long, coûteux et nécessitant une grande quantité de solvant pour
rééquilibrer et passiver le système fluidique de l’instrument.
Ce mémoire est une étude exploratoire qui vise à déterminer si ce type d’oligomères
d’acide cholique, une fois liés à des particules de gel de silice (6 μm de diamètre), montre la
formation de cavités moléculaires dans diverses conditions de phase mobile et s’il pourrait être
utilisé pour effectuer des séparations comme phase stationnaire bimodale. À notre connaissance,
il n’existe pas encore de phase stationnaire réversible à base d’oligomères d’acide cholique
capables d’interagir avec des composés hydrophiles et hydrophobes, en fonction de la polarité
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de l’éluant. Ce type de phase stationnaire se compare à d’autres phases stationnaires bimodales
pouvant être utilisées en NPC ou en RPC, parmi lesquels on trouve entre autres des copolymères
amphiphiles, des structures organométalliques et des macromolécules comme les cyclodextrines
(CD). La nature bimodale de la phase stationnaire à base de CD rapporté dans la littérature est
assez similaire aux phases stationnaires des oligomères d’acide cholique de cette étude, grâce à
leur cavité hydrophobe naturelle et un extérieur hydrophile, mais sans toutefois que la cavité
soit réversible à cause de la rigidité de l’anneau CD.
Les particules de silice greffées avec des oligomères d’acide cholique ont été
empaquetées par suspension dans un tube capillaire en silice fondue de diamètre intérieur (ID)
de 250 μm pour former des colonnes capillaires de 10 cm de long. Les performances
chromatographiques en phase liquide des phases stationnaires ont été étudiées à l'aide d'un
instrument HPLC adapté aux colonnes capillaires et muni d’un détecteur d’absorption. Plusieurs
sondes-analytes sont étudiées dans ce mémoire pour caractériser la rétention causée par les
phases stationnaires dans diverses phases mobiles eau/organique. Des comportements en RPC
et d'interaction hydrophile (HILIC) ont été observés dans différentes plages de composition de
phase mobile eau/organique. Les tests ont montré que les matériaux étaient capables de retarder
des analytes non polaires avec une diminution du pourcentage organique (% org) sur une large
plage de compositions (45% à 0% org dans le cas des alkylbenzènes). Les cavités hydrophobes
semblent quant à elles être responsables de la rétention aux % org moins que 10% et pour
seulement une faible partie de la plage totale de la rétention hydrophobique. Le comportement
en phase inverse a été comparé aux colonnes classiques à base de chaînes alkyles (C3, C4, C8
et C18) pour évaluer l’importance des interactions hydrophobes. Inversement, une augmentation
du % org, en particulier de l'acétonitrile, a entraîné la rétention de composés polaires sur une
courte plage de composition de solvant à partir de 85% org. Cette dernière rétention est toutefois
principalement imputable aux mécanismes HILIC avec le support de silice gel découvert et non
aux cavités hydrophiles du dimère d’acide cholique. / Over the past ten years, interesting oligomeric compounds based on cholic acids have
been synthesized and characterized by our collaborators from the Julian X.X Zhu group at the
Université de Montréal (UdeM). In a recent work, they synthesized a cholic acid dimer and
showed that it could form invertible molecular pockets when dissolved in media of different
polarity; in water, the dimer forms hydrophobic pockets, and in organic media, the dimer forms
hydrophilic pockets. Therefore, these amphiphilic compounds, when in solution, demonstrate
molecular pocket behavior depending on solvent conditions to form a cavity of opposite polarity
of the media in which they are located. The inversion behavior results from the conformational
flexibility of the chemical linker between the bile acid monomers. The ability of the pockets to
trap probe species based on their polarity suggests that the cholic acid oligomers might be
interesting stationary phases for high-performance liquid chromatography (HPLC), where
separation is based on solute polarity relative to the mobile phase. Since these materials can
produce hydrophobic and hydrophilic pockets, they could be exploited in both normal-phase
chromatography (NPC) and reversed-phase chromatography (RPC). The ability to have an
invertible stationary phase with suitable bimodal affinity could be advantageous in biosciences,
environmental sciences, and for the separation of complex mixtures by widening the field of
application of the same chromatographic column. The bimodal affinity may, in particular, make
it possible to avoid changing the operating mode of the HPLC; a costly and lengthy process
requiring a large amount of solvent to re-equilibrate and passivate all fluidic paths of the
instrument.
This memoir is an exploratory study that sets out to evaluate whether this type of cholic
acid oligomer, once bonded to silica gel particles (6 μm diameter), shows the formation of
molecular pockets in various mobile phase conditions and if they can be used to perform
separations as bimodal stationary phases. To the best of our knowledge, invertible stationary
phases based on cholic acid oligomers that are capable of selective binding and release of both
hydrophilic and hydrophobic compounds depending on the polarity of the eluent do not yet
exist. This type of stationary phase can be compared to the other bimodal stationary phases that
can be used in either NPC or RPC that includes amphiphilic copolymers, organometallic
structures and macromolecules like cyclodextrins (CD). The bimodal nature of the CD-based
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stationary phases are quite similar to the cholic acid oligomers stationary phases of this study,
thanks to a natural hydrophobic cavity and a hydrophilic exterior, but without the invertibility
of the cavity due to the rigidity of the CD ring.
The grafted particles were slurry-packed into 250 μm inner diameter (ID) fused silica
tubing to make 10 cm long capillary columns. The liquid chromatographic performance of the
stationary phases was investigated using a capillary HPLC instrument with a UV absorbance
detector. Several probe analytes were investigated to characterize the molecular pocket-based
retention in various water/organic mobile phases. RPC and hydrophilic interaction (HILIC)
behaviors were observed in distinctive composition ranges of water/organic mobile phases. The
tests showed that the materials were able to retain nonpolar compounds gradually with the
decrease of percentage organic (% org) over a wide range of compositions (45% to 0% org for
alkylbenzenes). The hydrophobic pockets seem to be responsible for the retention at % org less
than 10% and only for a small extent of the total range of the hydrophobic retention. The
reversed phase behavior was compared to classical alkyl-chain-based columns (C3, C4, C8 and
C18) to assess the importance of the hydrophobic interactions. Conversely, an increase in %
org, especially acetonitrile, resulted in the retention of polar compounds over a smaller range of
% org starting at 85% org. This latter retention is mainly attributable to HILIC mechanisms with
the uncapped silica gel support and not the cholic acid dimer hydrophilic pockets.
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Utopia, Kinship, and DesireCarroll, Jordan S. 13 June 2008 (has links)
No description available.
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Dispositifs optoélectroniques à base de semi-conducteurs organiques en couches mincesBrunner, Pierre-Louis Marc 08 1900 (has links)
No description available.
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