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Shaaban, M. G. B. "Scale-up studies on anaerobic dispersed growth digesters." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372310.
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Salin, Irene. "Scale-up studies for thermo-oxidative stability of polymeric composites /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/9871.
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Yeboue, Kouadio Yves. "Peptide Synthesis by Mechanochemistry : From Fundamental studies to Scale-Up." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS077.
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Compte tenu du durcissement des politiques environnementales vis-à-vis des polluants produits par l’industrie chimique et de la demande croissante de la part des consommateurs et des citoyens, il est impératif de trouver des méthodes alternatives aux procédés utilisant des quantités importantes de solvants et réactifs nocifs pour la santé et l’environnement. Les méthodes classiques de synthèse de peptides en font partie et nécessitent impérativement des améliorations. Ce manuscrit décrit les récents développements des procédés mécanochimiques en synthèse peptidique, procédés qui permettent un changement de paradigme par rapport aux procédés classiques utilisant des solvants. Ces procédés mécanochimiques sont utilisés au cours de cette thèse pour solutionner des problèmes d’épimérisation de peptides fréquemment rencontrés lors de l’emploi de la stratégie de couplage par fragment en solution. La preuve de faisabilité du couplage peptidique par ligation chimique native par broyage à billes a également été apportée au cours de cette thèse. L’approche de synthèse peptidique par mécanochimie a enfin été utilisée pour mettre au point des conditions efficaces permettant de monter en échelle la synthèse de peptides en utilisant le procédé d’extrusion réactive, ouvrant les portes à un transfert de la synthèse à l’échelle industrielle. L’ensemble de ces conditions mécanochimiques se sont avérées particulièrement efficaces quant à la synthèse de peptides avec des temps de réaction très faibles, d’excellents rendements, des taux d’épimérisation très faibles, un faible impact environnemental et une grande productivitéDue to the restriction of the environmental policies regarding the pollutants, it is urgent to find alternative methods to the processes that used large amount of highly toxic solvents and chemicals. Because of their negative environmental impact, conventional peptide synthesis methods require improvements. The use of mechanochemical processes allow to efficiently reduce the environmental impact by eliminating or replacing toxic solvents and chemicals. During this work, mechanochemical methods have been used to solve the peptide epimerization issues, frequently encountered during peptide fragment coupling strategy in solution. Additionally, by using these methods, peptide synthesis through native chemical ligation was also demonstrated. Furthermore, the use of the reactive extrusion process has enabled to efficiently work on large scale, thereby opening the boulevard to implement the peptide mechanosynthesis in industries. Finally, these methods have led to the desired peptides with noteworthy isolated yields, very short reaction times, low epimerization rate, low environmental impact and high productivity
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Stoker, Emily B. "Comparative Studies on Scale-Up Methods of Single-Use Bioreactors." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/889.
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This study was performed to increase knowledge of oxygen mass transfer (kLa) and mixing times in the scale-up of disposable bioreactors.Results of oxygen mass transfer studies showed kLa to increase with increasing agitation and aeration rates. By maintaining a scale-up constant such as gassed power to volume or shear, an almost constant kLa was achieved during scale-up from 50 to 2000 L. Using the scale-up constant Pg/V resulted in statistically higher kLa values at greater reactor volumes. Mixing times were revealed to be significantly affected by agitation, but not by the aeration rates tested. No pattern was recognized in the mixing time data over an increase in volume.
Commonly used methods for predicting kLa upon scale-up were compared to experimental data. New coefficients were determined to fit the historic models to the parameters of this study, namely the unique geometry and low agitation and aeration rates used in the single-use systems. Each of the resulting four models was found to have average error rates from 16-23%. Although the error rates are not statistically different, the Moresi and Patete model was determined to be most conceptually accurate. The Moresi and Patete model found kLa to be more dependent on aeration than on the power input. This finding was consistent with the results of the experimental studies.
The results of this study were for aeration rates (0.02-0.04 vvm) and agitation rates (Pg/V range of 2-20 W/m3) that are commonly used in single-use bioreactor systems.
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Dickson, Nicola Jane. "The scale-up of protein microfiltration based on laboratory studies of fundamental effects." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322703.
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Platon, Rolando R. "Scale-up studies on the culture of brine shrimp Artemia fed with rice bran." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25959.
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The effects of water movement or agitation on the biological performance of planktonic organisms under intensive culture have been rarely studied quantitatively. Stagnation or minimum values are considered important in the problem of scale-up based on optimum conditions. Near stagnation, inadequate water movement brings about undesirable effects, e.g. accumulation of metabolites, uneven distribution of feed and low dissolved oxygen concentration. An important mechanism associated with water movement at these conditions is the oxygenation process which defines the oxygen transfer rate from the gas to the water.
Experiments were conducted using potable water to determine the overall oxygen mass transfer coefficient in two types of container geometries; a) cylindri-conical tank and b) oblong-shaped center- partitioned raceway. For each type of container, three geometrically similar sizes were investigated with scale ratio of approximately 1:2:3.5. Agitation was induced by the introduction of air into the system. General correlations for both tank geometries were obtained from experimental data and were expressed in terms of the operating and geometric parameters. The correlations are in the form of dimensionless groups (Froude and Reynolds numbers) making them appropriate for scale-up estimates.
The general correlations for the overall oxygen mass transfer coefficient were subsequently used to provide the scaling equations to define the operating parameters in different sizes of containers for the culture of brine shrimp in sea water fed with rice bran. The high correlation coefficient obtained for the relationship between total brine shrimp biomass production and the overall mass transfer coefficient applicable to different sizes of both the cylindri-conical tank and the raceway indicates that the overall oxygen mass transfer coefficient is an effective scale-up criterion in brine shrimp culture.Graduate and Postdoctoral Studies
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Jin, Kai. "Studies of the scale-up of production and recovery of recombinant proteins formed as inclusion bodies." Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324597.
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Dai, Jianming. "Microwave-assisted extraction and synthesis studies and the scale-up study with the aid of FDTD simulation." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100342.
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The research undertaken in this thesis includes microwave-assisted extraction (MAE), synthesis, and the investigation of the scale-up of the microwave-assisted processes with the numerical aid.The main goal of this research is to study the various problems associated with the scale-up of the microwave-assisted extraction and synthesis processes. Laboratory studies were carried out to investigate the microwave-assisted extraction of known components from peppermint leaves and American ginseng. Various factors that influence the extraction processes were studied. Microwave-assisted extraction method was compared with conventional heating and room temperature extraction methods on the extraction of ginsenosides from American ginseng. Microwave-assisted extraction method was determined to have higher extraction rate than both room temperature extraction and reflux temperature extraction using hotplate heating indicating that there is acceleration factor in enhancing the extraction rate beyond the temperature influence.
In the study of synthesizing n-butyl paraben, microwave-assisted synthesis was observed to greatly increase the yield of n-butyl paraben in much shorter period of time compared to the classic synthesis method. A transition state theory was proposed to explain this rate enhancement. The study of the synthesis of parabens with different alcohol and the influencing factors on the synthesis of n-butyl paraben yield were also studied.
A visualization method was developed to determine the microwave distribution in a domestic microwave cavity. The method uses gypsum plate as carrier and cobalt chloride as indictor. A simulation program was developed using the finite difference time domain (FDTD) approach and written in C programming language. The program was proved to be very versatile in different type of cavity simulation. Not only cavities with different dimensions and geometrical designs can be simulated, multiple magnetrons and various ways of magnetron placement can also be integrated into the simulation program. The detailed power distribution can be visualized in a 3-D plot, and the power distribution in each layer can be analyzed using the simulation result. The power distribution information will be very useful and necessary before any real equipment development.
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Evans, Sarah Frances. "Top Down and Bottom Up Approaches to Elucidating Multiscale Periosteal Mechanobiology: Tissue Level and Cell Scale Studies." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1331646902.
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Bell, Alexander. "Studies on exploration and exploitation : concepts, roles and dynamics." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLED077.
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L’intensité concurrentielle et les évolutions technologiques n’ont jamais été aussi intenses. Aussi, les entreprises en quête de pérennité sont-elles de plus en plus confrontées à une nécessité d’exploiter leurs activités actuelles et d’explorer des activités futures. Or la gestion de ce double impératif est loin d’être évidente, générant potentiellement d’importantes tensions au sein des entreprises. Bien que la recherche en management ait permis de mieux appréhender cette tension d’Exploration/Exploitation, il reste des zones de contradiction et des espaces non explorés. En particulier, il n’y a pas de consensus sur les définitions des concepts d’exploration et d’exploitation, ne permettant pas ainsi de garantir une certaine cohérence dans la recherche (Birkinshaw & Gupta, 2013). D’autre part, la tension Exploration/Exploitation n’a que très peu été étudiée dans le contexte des jeunes entreprises de croissance - également appelées « scale-up » - qui ont la particularité d’être exposées à de forts enjeux de survie. Ainsi, afin de contribuer à une meilleure compréhension des problématiques que soulève cette tension au sein de celles-ci, un format de thèse sur travaux, comprenant trois études complémentaires, est adopté.Au préalable, afin de cadrer conceptuellement la thèse, je réponds, dans une première étude, à l’appel des chercheurs pour la clarification des concepts d’exploration et d’exploitation en proposant une typologie d’exploration. Puis, par l’intermédiaire d’une approche multi-cas longitudinale menée auprès de huit jeunes entreprises de croissance, j’explore tout d’abord, dans une deuxième étude, les facteurs influençant les orientations stratégiques des entreprises quant à leurs activités d’exploration et d’exploitation. Enfin, dans la troisième étude, je cherche à comprendre comment le fonctionnement des équipes de direction définit les rôles de chacun dans les activités d’exploration et d’exploitationCompetition and technological change have never been as intense as they are today. To survive, companies must increasingly carry out current activities at the same time that they explore future ones. It is no easy task to operate on both of these fronts, and doing so is a potential source of tension and contradiction. Although management research has provided insight into the exploration and exploitation tension, there are still contradictions and unexplored areas. In particular, there is no consensus on the definition of the concepts of exploration and exploitation, which means the research lacks a certain level of consistency. In addition, there has been very little attention paid to the Exploration/Exploitation tension in the context of young, growing “scale-up” companies, which are particularly exposed to threats to their survival. To obtain a better understanding of the situations this tension causes in these companies, we have adopted a multi-paper dissertation consisting of three complementary studies.In the first study, to create a conceptual framework for the thesis, we answer researchers’ call for a clarification of the concepts of exploration and exploitation by proposing a typology of exploration. Then, based on a longitudinal, multi-case approach focused on eight scale-up companies, we first explore, in a second study, the factors influencing firms’ strategic orientations vis-à-vis exploration and exploitation activities. Finally, in the third study, we seek to understand how management teams define their individual roles with respect to exploration and exploitation activities
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Kohon, Jacklyn Nicole. "Building Social Sustainability from the Ground Up: The Contested Social Dimension of Sustainability in Neighborhood-Scale Urban Regeneration in Portland, Copenhagen, and Nagoya." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2330.
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In response to growing social inequality, environmental crises, and economic instability, sustainability discourse has become the dominant "master signifier" for many fields, particularly the field of urban planning. However, in practice many sustainability methods overemphasize technological and economic growth-oriented solutions while underemphasizing the social dimension. The social dimension of sustainability remains a "concept in chaos" drawing little agreement on definitions, domains, and indicators for addressing the social challenges of urban life. In contrast, while the field of public health, with its emphasis on social justice principles, has made significant strides in framing and developing interventions to target the social determinants of health (SDH), this work has yet to be integrated into sustainability practice as a tool for framing the social dimension. Meanwhile, as municipalities move forward with these lopsided efforts at approaching sustainability practice, cities continue to experience gentrification, increasing homelessness, health disparities, and many other concerns related to social inequity, environmental injustice, and marginalization. This research involves multi-site, comparative case studies of neighborhood-scale sustainability planning projects in Portland, U.S.; Copenhagen, Denmark; and Nagoya, Japan to bring to light an understanding of how the social dimension is conceptualized and translated to practice in different contexts, as well as the challenges planners, citizen participants, and other stakeholders encounter in attempting to do so. These case studies find that these neighborhood-scale planning efforts are essentially framing the social dimension in terms of principles of SDH. Significant challenges encountered at the neighborhood-scale relate to political economic context and trade-offs between ideals of social sustainability, such as social inclusion and nurturing a sense of belonging when confronted with diverse neighborhood actors, such as sexually oriented businesses and recent immigrants. This research contributes to urban social sustainability literature and sustainability planning practice by interrogating these contested notions and beginning to create a pathway for integration of SDH principles into conceptualizations of social sustainability.
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Mazzoleni, Giorgio. "Feasibility, optimisation and scale-up studies for the production of P. falciparum putative vaccine candidates for a malaria microarray-based antigenicity screening." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9510.
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Malaria is a tropical parasitic disease spread worldwide by protozoan parasites of the genus Plasmodium. Attempts to eradicate or control the disease have largely failed and the weapon-of-choice in combating malaria, a vaccine, still eludes us. Now that the Plasmodium falciparum (Pf ) genome has been revealed, it is essential to search for new potential antigens. On that basis, my project aims to select and produce putative vaccine candidates that together with protein microarray techniques will unravel possible correlates of protection against the human malaria parasite Pf, responsible for the majority (90%) of deaths from malaria. My PhD project forms part of FightMal a consortium-based study that first use bioinformatic analysis to identify those proteins within the Pf proteome that are known or anticipated to be either anchored on the parasite/infected host cell surface or secreted. Such in silico analysis produced 3 ‘candidate lists’ of interest, one for each of the 3 types of protein chips planned for production: i) current vaccine candidates (n.25), ii) putative immune targets (n.260), iii) variant surface antigens, VSA (n.74). Candidates belonging to CHIP 2 were cloned and expressed (in vivo) using customized high-throughput platforms. To date, 394 (88%) Chip 2 DNA targets have been successfully amplified by PCR, 325 (82%) of these have been inserted into the expression plasmid and sequenced. A total of 269 constructs resulted suitable for heterologous expression. Due to the complexity of soluble expression of plasmodial proteins a number of different expression conditions were tested. Both the strain of the E. coli host and the composition of the expression medium resulted crucial variables for satisfactory results. Via a multi-step optimisation phase we increased the initial number of soluble candidates from 18% to 44%, which eventually led to a 6-fold increase in the number of targets available for purification. During an early evaluation study, 77% (10/13) of the recombinant proteins produced in large-scale were purified using embedded affinity tags yielding a ≥90% purity level. Preliminary results, obtained spotting 40 in vitro expressed Pf candidates, successfully demonstrated the potentials of the protein microarray technology as an efficient serum-based multiplex assay capable of identifying new antigens. Using an optimised protocol, over 7000 antigen-antibody interactions were evaluated. 92% of the Pf protein panel was recognised by both total and cytophilic IgGs, with 6 novel candidates resulting as antigenic as some of the antigens evaluated in vaccine clinical trials for malaria. It is envisaged that my PhD will deliver multi-level technical know-how, which could improve the production and evaluation of novel plasmodial vaccine candidates. The final Pf microarray will be employed to screen clinical samples collected from protected and non-protected children enrolled in a longitudinal, case-control study in an area of Uganda where malaria is endemic. It is expected that the FightMal project overall will eventually generate novel immunological data and information pertaining to both the complexity of the plasmodial proteome and variability of the naturally-induced immune response against the malaria parasite.
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Duncan, Kester. "REM: Relational Entropy-Based Measure of Saliency." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1620.
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The incredible ability of human beings to quickly detect the prominent or salient regions in an image is often taken for granted. To be able to reproduce this intelligent ability in computer vision systems remains quite a challenge. This ability is of paramount importance to perception and image understanding since it accelerates the image analysis process, thereby allowing higher vision processes such as recognition to have a focus of attention. In addition to this, human eye fixation points occurring during the early stages of visual processing, often correspond to the loci of salient image regions. These regions provide us with assistance in determining the interesting parts of an image and they also lend support to our ability to discriminate between different objects in a scene. Salient regions attract our immediate attention without requiring an exhaustive scan of a scene. In essence, saliency can be defined as the quality of an image region that enables it to stand out in relation to its neighbors.
Saliency is often approached in either one of two ways. The bottom-up saliency approach refers to mechanisms which are image-driven and independent of the knowledge in an image, whereas the top-down saliency approach refers to mechanisms which are task-oriented and make use of the prior knowledge about a scene. In this thesis, we present a bottom-up measure of saliency based on the relationships exhibited among image features. The perceived structure in an image is determined more by the relationships among features rather than the individual feature attributes. From this standpoint, we aim to capture the organization within an image by employing relational distributions derived from distance and gradient direction relationships exhibited between image primitives. The Rényi entropy of the relational distribution tends to be lower if saliency is exhibited for some image region in the local pixel neighborhood over which the distribution is defined. This notion forms the foundation of our measure.
Correspondingly, results of our measure are presented in the form of a saliency map, highlighting salient image regions. We show results on a variety of real images from various datasets. We evaluate the performance of our measure in relation to a dominant saliency model and obtain comparable results. We also investigate the biological plausibility of our method by comparing our results to those captured by human fixation maps. In an effort to derive meaningful information from an image, we investigate the significance of scale relative to our saliency measure, and attempt to determine optimal scales for image analysis. In addition to this, we extend a perceptual grouping framework by using our measure as an optimization criterion for determining the organizational strength of edge groupings. As a result, the use of ground truth images is circumvented.
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Helen, Onyeaka. "Studies related to scale-up of high cell density Escherichia Coli fed-batch fermentations : effect of a changing micro-environment with respect to pH, glucose and oxygen concentration." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.668327.
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Blanchard, Monica R. "Using Network Models to Predict Steelhead Abundance, Middle Fork John Day, OR." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4477.
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In the management of threatened and endangered species, informed population estimates are essential to gage whether or not recovery goals are being met. In the case of Pacific salmonids, this evaluation often involves sampling a small subset of the population and scaling up to estimate larger distinct populations segments. This is made complicated by the fact that fish populations are not evenly distributed along riverscapes but respond to physical and biological stream properties at varying spatial extents. We used rapid assessment survey methods and the River Styles classification to explore fish-habitat relationships at a continuous network scale. Semi-continuous surveys were conducted across nine streams in the upper Middle Fork John Day River watershed and increased the number of sites surveyed eight-fold over other monitoring methods within the watershed. Using this increased sample size and continuous habitat metrics we improved watershed-wide steelhead (Oncorhynchus mykiss) abundance models.
We first validated the distinctions among River Styles through a classification analysis using physical metrics measured at the rapid assessment sites. Overall classification accuracy, using a combination of reach and landscape scale metrics, was 88.3% and suggested that River Style classification was identifying variations in physical morphology within the watershed that was quantifiable at the reach scale. Leveraging the continuous River Styles classification of physical habitat and a continuous model of primary production improved the prediction of steelhead abundance across the network. Using random forest regressions, a model that included only habitat metrics resulted in R2 = 0.34, while using the continuous variables improved the model accuracy greatly to R2 = 0.65. Random forest allowed for further investigation into the predictor variables through the analysis of the partial dependence plots and identified a gross primary production threshold, below which production might be limiting steelhead populations. This method also identified the rarest River Style surveyed within the watershed, Confined-Valley Step Cascade, as the morphology that had the largest marginal effect on steelhead. The inherent physical properties and boundary conditions unique to each River Style has the potential to inform fish-habitat relationships across riverscapes and improve abundance estimates on a continuous spatial scale.
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Luniwal, Amarjit. "Design, Synthesis, and Process Chemistry Studies of Agents Having Anti-Cancer Properties." University of Toledo Health Science Campus / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=mco1302801948.
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Kuokkanen, V. (Ville). "Utilization of electrocoagulation for water and wastewater treatment and nutrient recovery:techno-economic studies." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526211084.
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Abstract Electrocoagulation (EC) is an emerging technology that combines the functions and advantages of conventional coagulation, flotation, and electrochemistry in water and wastewater treatment. The aims of this work included doing an updated literary review of recent feasible applications of EC, which were found to be plentiful. Since the economic and practical operational key figures related to EC haven’t been extensively mapped out before, this was a prime objective of this part of the work. The aim of the next part of this work was to find new feasible applications for EC in the treatment of water and wastewater. The studied wastewaters included bio- and synthetic oil-in-water emulsions, various industrial nutrient-containing wastewaters, and peat bog drainage water containing humic substances (an interesting and topical problem, especially in Finland). These studies proved the feasibility of EC. In addition, larger-scale experiments were also conducted successfully, thus proving the scalability of the EC process. Extensive economic analyses of the studied EC applications were also done. The operational costs and energy consumption of EC were found to be very low—typically about 0.1–1.0 €/m3 and 0.4–4.0 kWh/m3. It has been forecasted that in the future there will be a shortage of virgin phosphorus. Therefore, another essential purpose of this work was to conduct a preliminary study on the feasibility of using EC for nutrient (especially phosphorus, but also nitrogen) removal and recovery from different types of real wastewater. Specifically, it may be possible to use EC sludges containing notable amounts of phosphorus and nitrogen as additives in granulated bio ash-based fertilizer products for various applications. This is a novel idea and a “hot topic” in the waste utilization sector and in circular and bioeconomyTiivistelmä Elektrokoagulaatio (electrocoagulation, EC) on nosteessa oleva teknologia, joka yhdistää perinteisen koagulaation, flotaation ja sähkökemian hyödyt ja mahdollisuudet vesien ja jätevesien käsittelyssä. Tämän työn ensimmäisenä tavoitteena oli laatia kirjallisuuskatsaus EC:n viimeaikaisista käyttökelpoisista sovelluksista, joita löytyi runsaasti. Koska EC:n toiminnallisia ja taloudellisia avainlukuja ei ole kartoitettu kattavasti aiemmin, tämän tekeminen oli tämän osion tärkein tavoite. Väitöstyön seuraavana tavoitteena oli löytää uusia sovellutuksia EC:lle vesien ja jätevesien käsittelyssä. Tutkittuja vesiä olivat bio- ja synteettisistä öljyistä valmistetut öljy-vesiemulsiot, erilaiset teolliset ravinnepitoiset jätevedet ja humusainepitoiset turvesoiden valumavedet (kiinnostava ja ajankohtainen ongelma, erityisesti Suomessa). EC todettiin käyttökelpoiseksi teknologiaksi näissä kokeissa. Suuremman skaalan kokeilla todistettiin lisäksi EC-prosessin skaalautuvuus. Lisäksi, em. EC-sovellutuksista suoritettiin kattavat taloudelliset analyysit. EC:n käyttökustannukset ja energiankulutus todettiin erittäin pieniksi, tyypillisesti ne olivat välillä 0.1–1.0 €/m3 ja 0.4–4.0 kWh/m3. On ennustettu, että tulevaisuudessa on pulaa neitseellisestä fosforista. Tästä johtuen eräs tämän työn keskeisistä tarkoituksista oli suorittaa alustavia kokeita liittyen EC:n käyttökelpoisuuteen ravinteiden (erityisesti fosfori, mutta myös typpi) poistossa ja talteenotossa aidoista jätevesistä. Erityisesti jatkossa voisi olla järkevää hyödyntää runsaasti fosforia ja typpeä sisältäviä EC-sakkoja lisäaineina rakeistetuissa biotuhkapohjaisissa lannoitteissa eri sovellutuksissa. Tämä idea on uusi ja on jo herättänyt suurta kiinnostusta mm. kierto- ja biotaloussektoreilla
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Mercer, James Mark. "Studies related to the operation and scale-up of high-cell density Pichia pastoris fermentation processes : effects on cell physiology of a changing micro-environment with respect to glycerol, methanol, and oxygen concentrations as well as pH." Thesis, University of Birmingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433697.
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Ferchichi, Mouna. "Synthèse, fonctionnalisation et étude conformationnelle de calixarènes comportant 7, 9, 10 et 12 unités." Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10082.
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Le travail de cette thèse a permis tout d’abord d’aboutir à un protocole simplifié pour la synthèse des p-tert-butylcalix[7] et [9]arènes, composés jusqu’à lors difficilement préparables. Ces macrocycles ont été obtenus en grosse quantité, de l’ordre de la dizaine de gramme. Il faut également noter que cette synthèse sur grande échelle permet d’obtenir les p-tert-butylcalix[10] et [12]arènes avec des rendements modestes mais une simplicité remarquable. A partir de ces calixarènes, deux voies principales de per-fonctionnalisation ont été mises en oeuvre : La réaction de Williamson, consistant à former des éthers, et l’estérification via l’utilisation d’anhydrides. Au total, ce sont 10 nouveaux calixarènes fonctionnalisés qui ont été obtenus. Le comportement dynamique et conformationnel des calix[9]arènes originaux a été évalué en solution et à l’état solide. Dans le cas où cela a été possible, la détermination des constantes de vitesse et d’énergie libre des mouvements conformationnels a montré que ces calix[9]arènes fonctionnalisés étaient très mobiles. En outre, trois nouvelles structures RX ont été obtenues et ont confirmé que ces macrocycles adoptaient une conformation désordonnée. En l’état, ces nouveaux calixarènes ne sont pas des candidats de choix pour devenir des hôtes moléculaires efficaces. Toutefois, ce travail a permis d’améliorer nos connaissances sur des structures dérivées de p-tert-butylcalix[n]arènes (n = 7, 9, 10 et 12) peu étudiés jusqu’à présentThe work of this thesis allowed to propose a simplified procedure for the synthesis of p-tertbutylcalix[ 7] and [9]arenes, which were hardly synthesizable until now. Those macrocycles were obtained in a large amount, about a dozen of grams. It’s important to emphasize that this large scale synthesis allow to obtain the p-tert-butylcalix[10] and [12]arenes with moderate yields but in a straight and simple procedure. From these calixarenes, two main ways of per-functionalization were attempted: Williamson reaction, consisting in forming ethers and esterification by using anhydrides. Totally, 10 new functionalized calixarenes were obtained. Their dynamic and conformational behaviors in solution as well as in the solid state were explored. The determination of the rate constants and of the free energy barrier of the conformational motion has shown that those compounds were mobile. Moreover, three original X-Ray structures were obtained and have revealed that those macrocycles adopted a disordered conformation. At this point, those new calixarenes are not well designed to act as efficient molecular host. However, this work allowed to improve our knowledges on structures made from the p-tert-butylcalix[n]arene (n = 7, 9, 10 and 12), a skeleton rarely described and studied up to now
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Viinikka, Claudia, and Pamela Svanberg. "FinTech-startups i Stockholm : En kvalitativ studie om hur FinTech-startups arbetar för att skala upp verksamheten." Thesis, Södertörns högskola, Företagsekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-35482.
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Dagens samhälle är digitaliserat och vi lever i ett paradigmskifte. Det sker en stor förändring inom finansmarknaden. Innovativa FinTech-startups tar över då traditionella finansinstitut inte klarar av att tillgodose kundernas ökade behov. Dessa FinTech-startups är viktiga och driver innovationen framåt i samhället och uppfyller kundernas allt högre krav. Dock har dessa företag svårigheter i att skala upp sin verksamhet vilket gör att de får svårigheter att överleva. Utmaningar de möter är främst inom finansiering och reglering. Syftet med studien är att undersöka hur FinTech-startups arbetar för att skala upp sin verksamhet samt hur de påverkas av och hanterar utmaningar i form av finansiering och reglering. Teorier som används är: FinTechs ekosystem, startups livscykel och teknologisk innovation. Studien är en kvalitativ undersökning med ett abduktivt angreppssätt och datainsamlingen har gjorts genom semistrukturerade intervjuer med personer från sex stycken Stockholmsbaserade FinTech-startups. Studiens resultatet visar att FinTech-startups möjligheter för att skala upp verksamheten till störst del är beroende av den finansiering som de får in. Dock upplever företagen svårigheter i att hitta investerare och hamnar i en ond cirkel. Tillstånd som krävs har en stor påverkan på företagens möjlighet att skala upp.Digitizaliation charactarizes todays society and a new paragdim is a fact. There are considerable changes within the financial market where innovative FinTech-startups more and more take over the industry. This, due to that the traditional institutions cannot meet the costumers demands. The FinTech-startups are essential for the society and drives the innovation forward in order to fulfill the costumers requirements. However, these start-ups face difficulties with scaling-up which makes it hard for them to survive on the market. Financial funds and regulations are the main challanges they need to overcome. The purpose with this thesis is to examine how FinTech-startups work in order to scale-up their business and how they face challenges as financing and regulation. Theories used in this thesis are: FinTechs ecosystem, Startups life cycle and Technological innovation. A qualitative method is used with semistructured interviews with people from six different FinTech-startups based in Stockholm. The result of the studie shows that the FinTech-startups possibility to scale up mostly depends on financial funds. The companies experience challenges in finding investors and are placed in a vicious circle. In addition, conditions required have a major impact on the abilities to scale-up their business.
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Thomson, Grant. "Community small scale wind farms for New Zealand: a comparative study of Austrian development, with consideration for New Zealand’s future wind energy development." Lincoln University, 2008. http://hdl.handle.net/10182/961.
Full textAbstract:
In New Zealand, the development of wind energy is occurring predominantly at a large scale level with very little opportunity for local people to become involved, either financially or conceptually. These conditions are creating situations of conflict between communities and wind energy developers – and are limiting the potential of the New Zealand wind energy industry. The inception of community ownership in small scale wind farms, developed in Europe in the late 20th Century, has helped to make a vital connection between wind energy and end users. Arguably, community wind farms are able to alleviate public concerns of wind energy’s impact on landscapes, amongst a wide range of other advantages. In Austria, community wind farms have offered significant development opportunities to local people, ushered in distributed generation, and all the while increasing the amount of renewable energy in the electricity mix. This thesis investigates whether community small scale wind (SSW) farms, such as those developed in Austria, are a viable and feasible option for the New Zealand context. The approach of this thesis examines the history of the Austrian wind industry and explores several community wind farm developments. In addition, interviews with stakeholders from Austria and New Zealand were conducted to develop an understanding of impressions and processes in developing community wind energy (CWE) in the New Zealand context. From this research an assessment of the transfer of the Austrian framework to the New Zealand situation is offered, with analysis of the differences between the wind energy industries in the two countries. Furthermore, future strategies are suggested for CWE development in New Zealand with recommendations for an integrated governmental approach. This research determines that the feasibility for the transfer of the Austrian framework development of ‘grassroots’ community wind farms in the next 10 years is relatively unlikely without greater support assistance from the New Zealand Government. This is principally due to the restricted economic viability of community wind farms and also significant regulatory and policy limitations. In the mid to long term, the New Zealand government should take an integrated approach to assist the development of community wind farms which includes: a collaborative government planning approach on the issue; detailed assessment of the introduction of feed-in tariff mechanisms and controlled activity status (RMA) for community wind farms; and development of limited liability company law for community energy companies. In the short term, however, the most feasible option available for the formation of community wind farms lies in quasi community developments with corporate partnerships.
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Lyshall, Linda. "Collaboration and Climate Action at the Local Scale." Antioch University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1303754240.
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Mallangi, Siva Sai Reddy. "Low-Power Policies Based on DVFS for the MUSEIC v2 System-on-Chip." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229443.
Full textAbstract:
Multi functional health monitoring wearable devices are quite prominent these days. Usually these devices are battery-operated and consequently are limited by their battery life (from few hours to a few weeks depending on the application). Of late, it was realized that these devices, which are currently being operated at fixed voltage and frequency, are capable of operating at multiple voltages and frequencies. By switching these voltages and frequencies to lower values based upon power requirements, these devices can achieve tremendous benefits in the form of energy savings. Dynamic Voltage and Frequency Scaling (DVFS) techniques have proven to be handy in this situation for an efficient trade-off between energy and timely behavior. Within imec, wearable devices make use of the indigenously developed MUSEIC v2 (Multi Sensor Integrated circuit version 2.0). This system is optimized for efficient and accurate collection, processing, and transfer of data from multiple (health) sensors. MUSEIC v2 has limited means in controlling the voltage and frequency dynamically. In this thesis we explore how traditional DVFS techniques can be applied to the MUSEIC v2. Experiments were conducted to find out the optimum power modes to efficiently operate and also to scale up-down the supply voltage and frequency. Considering the overhead caused when switching voltage and frequency, transition analysis was also done. Real-time and non real-time benchmarks were implemented based on these techniques and their performance results were obtained and analyzed. In this process, several state of the art scheduling algorithms and scaling techniques were reviewed in identifying a suitable technique. Using our proposed scaling technique implementation, we have achieved 86.95% power reduction in average, in contrast to the conventional way of the MUSEIC v2 chip’s processor operating at a fixed voltage and frequency. Techniques that include light sleep and deep sleep mode were also studied and implemented, which tested the system’s capability in accommodating Dynamic Power Management (DPM) techniques that can achieve greater benefits. A novel approach for implementing the deep sleep mechanism was also proposed and found that it can obtain up to 71.54% power savings, when compared to a traditional way of executing deep sleep mode.Nuförtiden så har multifunktionella bärbara hälsoenheter fått en betydande roll. Dessa enheter drivs vanligtvis av batterier och är därför begränsade av batteritiden (från ett par timmar till ett par veckor beroende på tillämpningen). På senaste tiden har det framkommit att dessa enheter som används vid en fast spänning och frekvens kan användas vid flera spänningar och frekvenser. Genom att byta till lägre spänning och frekvens på grund av effektbehov så kan enheterna få enorma fördelar när det kommer till energibesparing. Dynamisk skalning av spänning och frekvens-tekniker (såkallad Dynamic Voltage and Frequency Scaling, DVFS) har visat sig vara användbara i detta sammanhang för en effektiv avvägning mellan energi och beteende. Hos Imec så använder sig bärbara enheter av den internt utvecklade MUSEIC v2 (Multi Sensor Integrated circuit version 2.0). Systemet är optimerat för effektiv och korrekt insamling, bearbetning och överföring av data från flera (hälso) sensorer. MUSEIC v2 har begränsad möjlighet att styra spänningen och frekvensen dynamiskt. I detta examensarbete undersöker vi hur traditionella DVFS-tekniker kan appliceras på MUSEIC v2. Experiment utfördes för att ta reda på de optimala effektlägena och för att effektivt kunna styra och även skala upp matningsspänningen och frekvensen. Eftersom att ”overhead” skapades vid växling av spänning och frekvens gjordes också en övergångsanalys. Realtidsoch icke-realtidskalkyler genomfördes baserat på dessa tekniker och resultaten sammanställdes och analyserades. I denna process granskades flera toppmoderna schemaläggningsalgoritmer och skalningstekniker för att hitta en lämplig teknik. Genom att använda vår föreslagna skalningsteknikimplementering har vi uppnått 86,95% effektreduktion i jämförelse med det konventionella sättet att MUSEIC v2-chipets processor arbetar med en fast spänning och frekvens. Tekniker som inkluderar lätt sömn och djupt sömnläge studerades och implementerades, vilket testade systemets förmåga att tillgodose DPM-tekniker (Dynamic Power Management) som kan uppnå ännu större fördelar. En ny metod för att genomföra den djupa sömnmekanismen föreslogs också och enligt erhållna resultat så kan den ge upp till 71,54% lägre energiförbrukning jämfört med det traditionella sättet att implementera djupt sömnläge.
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He, Yan-Long. "Hydrodynamic and scale-up studies of spouted beds." Thesis, 1995. http://hdl.handle.net/2429/8724.
Full textAbstract:
The scaling relationships proposed by Glicksman (1984) for fluidized bed scale-up
have been modified to provide a full set of scaling parameters for spouted bed scale-up. A
force balance for particles in the annulus region leads to addition of two non-dimensional
parameters, the internal friction angle (φ) and the loose packed voidage (ε₀) to the
original Glicksman scaling relationships. Experimental verification of the full set of
modified scaling parameters was conducted, first in a series of small spouted beds, then in
larger columns up to 0.914 m in diameter, and finally in a pair of high temperature (500
°C) beds. Both viscous and inertial forces were important for the conditions investigated
so that no simplifications could be made to the full set of scaling parameters. It is
demonstrated that the full set of modified scaling parameters is valid for spouted beds
when all dimensionless parameters are matched between the prototype and model beds.
A fibre optic probe was used to measure voidage profiles in spouted beds of
diameter 0.152 m. The voidage in most of the annulus was found to be somewhat higher
than the loose-packed voidage and increased with increasing spouting gas flow rate,
contrary to usual assumptions. The voidage decreased with height in the core of the
fountain for low spouting gas flow rates, but first increased with height and then decreased
towards the top of the fountain at higher gas flow rates. Radial profiles of local voidage
were roughly parabolic in the lower portion of the spout and blunt in the upper portion.
The same fiber optic probe was also used to measure spout diameters based on
significantly higher counts of output electric pulses in the spout region than in the annulus.
The flat wall of semi-cylindrical spouted bed columns was found to cause considerable
distortion of spout shapes which became approximately semi-elliptical. The often-used
McNab (1972) equation was found to underestimate the spout diameters in a full-column,
with an average deviation of 35.5%.
A second fibre optic probe system was used to measure profiles of vertical particle
velocities in the spout and fountain regions. In addition, a fibre optic image probe was
employed to measure particle velocity profiles in the annulus. In the spout, radial profiles
of vertical particle velocities were near Gaussian in shape. Particle velocities along the
spout axis in a half-column were 70% lower than in a full-column of the same diameter as
the half-column under identical operating conditions. In the half column, particle velocities
adjacent to the front plate were approximately 24% lower than a few millimeters away for
the conditions studied. In the annulus region, there was a 28% difference between particle
velocities adjacent to the column wall and those only 2 mm away.
Measurements of pressure profiles and gas flow distributions in the annulus were
carried out, while the influence of elevated pressures on bed hydrodynamics was also
examined.
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Huang, Yu-Lun, and 黃于倫. "Stability Studies on Scale-Up of Nicorandil Tablets." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/71484848690472251970.
Full textAbstract:
碩士嘉南藥理科技大學
藥學系
101
Nicorandil is an anti-anginal drug, also represented as a model drug for the product stability evaluation during scale-up process in this study. This study is divided into five parts. In the first part, observed the stability of nicorandil market product which have different amount of moisture content, and referred the raw material been used from the best stability product for the further formulation development. In the second part, to develop the formulation and the manufacturing process that can be executed stably and easily by pre-formulation study. In the third part, to evaluate the effect of drug product properties after scale-up process, also the storage period and condition of semi-final product during the holding time. The result showed that the sufficient amount of desiccant is necessary for the storage stability maintenance during the holding time, also the physical characteristics and drug release property of nicorandil tablet has no significantly change after scale-up process. In the fourth part, to investigate the stability variance of nicorandil tablet under different package protection. The well moisture resistance package material and desiccant moisture absorption capacity offered the ability to defer the drug degradation and the increase of total impurities. In the last part, to evaluate the effect of the dissolution rate of nicorandil tablet in 0.1N hydrochloride acid dissolution test. The harder tablet obtained from stability test, the slower dissolution rate of nicorandil tablet. With these result, not only the nicorandil tablet characteristics have been investigated, but also as the basis of risk assessment for the drug stability of formulation development in the future.
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WU, CHAO-MING, and 吳朝明. "Studies on the scale up of aerated tumbling bed." Thesis, 1990. http://ndltd.ncl.edu.tw/handle/82603326957817842904.
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Chen, Pei-Chi, and 陳珮綺. "Studies on Sake making with glutinous rice and scale-up of fermentation process." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/67687639367517896047.
Full textAbstract:
碩士國立中興大學
食品科學系
93
Sake is a traditional alcoholic drink in Japan. Both saccharification and alcohol fermentation take place simultaneously in sake-brewing. The final alcohol content is about 15％ in average. In previous study, we had determined some key factors affected sake-brewing in laboratory scale. In this study, we investigated the feasibility of sake-brewing using various kind of glutinous rice in a larger scale and the effects of using different sake yeasts on fermentation. Besides, the feasibility of using glutinuous rice as raw material to obtain a sake with a novel flavor was also studied. The production of koji starter is usually a key step in an industrial sake-brewing. The optimal conditions of its cultivation and dehydration were determined. In the process of koji starter-making, 0.75％(w/w) charcoal and 0.1％(w/w) spore suspension were added to steamed rice and mix thoroughly. The inoculated steamed rice was then cultivated at 30℃ for 4 days, followed by dehydrated at 50℃ for 24 hours. In the study of a larger-scale sake-brewing, the final concentration of ethanol in mash was 17.47％(w/w) in average. Contents of both glucose and maltose in mash fell to zero at the end of fermentation. Lactic acid, malic acid and succinic acid are the major organic acids in fermented mash. The flavor related constituents, such as glucose, maltose and malic acid, were more dominant at the 29th day compared to those obtained at the 33th day in the sake mash. The concentration of ethanol in mash was 16.65％(w/w) at the 29th day. It was probable a better approach to shorten the fermentation day of sake-brewing by 4 days . The effects of using different sake yeasts on sake brewing was examined as follows. When each fermentation was performed by using two different yeast, Saccharomyce cerevisiae k901 and BCRC21679, a highest concentration with 17.3％(w/w) of ethanol was always obtained. And the rice varieties used didn’t cause an effect on the final ethanol concentration. There was no residual glucose or maltose in mash. The concentrations of organic acids showed a great variety divergency in values. When the japonica rice was used as raw material and fermented by a mixed culture of two yeast strains, the concentration of succinic acid was 1.012％(w/w) at the 29th day and 0.6021％(w/w) at the 33th day, They were the highest one among the test
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Gentile, Jaime. "The impact of antiretroviral treatement scale-up on health systems in South Africa : a qualitative study." Thesis, 2008. http://hdl.handle.net/10413/1116.
Full textAbstract:
This study investigates the impact of the scale-up of antiretroviral treatment (ART) on the
health system in South Africa. It looks at the positive and negative effects of treatment
scale-up on human resources and staff morale, on HIV prevention programmes, and on
other health system programmes, looking specifically at the integration of programmes
and the use of infrastructure. There is much debate as to the place of treatment as a
response to the epidemic because it has been found to be less cost-effective than
prevention interventions. However this study argues that it is difficult to accurately
assess cost effectiveness because it does not take into account other ways in which
treatment may be effective, such as its impact on other aspects of health care, most
notably on staff morale and on prevention. Thus this study investigates the impact of
treatment intervention on the health system as a whole in order to determine the
effectiveness of treatment as a policy response.
This research uses data collected in 2006 at two sites in South Africa: the Ilembe district
in KwaZulu-Natal province and the Cape Winelands Region in the Western Cape
province. Twenty-one health care professionals were interviewed across the two sites in
order to determine their perspectives on the impacts of ART scale-up on these aspects of
the health care system. Interviews were conducted at hospitals, clinics and on hospice
where ART was being administered
ART scale-up, as predicted, was having a mixed impact on the health system as a whole.
For the most part, the programmes were not having negative impacts on the rest of the
health system in the form of taking infrastructure, funding, or human resources from
other departments. The programmes, on separate budgets, were not directly taking
resources from other departments, although there were some instances of borrowing
space, staff, or equipment when necessary. The treatment programmes were reported to
be adding further strain to an already resource-limited health care system, which was
most notable in the issues of space and staff shortages. In addition, the treatment
programmes did not appear to be bringing in additional funding, staff development, or
infrastructure to benefit the health system as a whole.The major positive impact of the ART rollout on the health system was creating positive
staff morale and a sense of hope throughout the health system. The health system was
now able to address HIVIAIDS and was able to provide treatment whereas prior to rollout
there was little apart from palliative care that could be done for people living with
HIVIAIDS. In addition, treatment was adding to prevention efforts by raising awareness
in the community about HIV/AIDS and by increasing uptake of voluntary counseling and
testing.
There is a need to address the resource limitations in the health care system, most notably
human resource shortages. The success of treatment programmes was dependent on
having motivated and dedicated staff. It is necessary to further attract and retain health
care professionals to the field in order to ensure the sustainable success of ART rollout.
Funding also needs to be addressed to ensure that sustainable resources are available to
support the ever-growing needs of the treatment programmes.Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2008.
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Yang, Meng-Lin, and 楊孟霖. "Studies on The Factors Associated with Scale up and Cold Storage of The Two Diatoms Skeletonema costatum and Thalassiosira weissflogii." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/5vf869.
Full textAbstract:
碩士國立臺灣海洋大學
水產養殖學系
105
Two species of Coscinodiscophyceae, Skeletonema costatum and Thalassiosira weissflogii were assayed the effects of operation factors of cold storage or cultivation and quality maintenance at room temperature, aimed at the establishment of stable production of high quality food organism. This study was divided into three directions, isolation and purification, algae culture at room temperature, and cold storage. The best way of algae isolation is to use the capillary method to collect the algae, filtrated and remove the impurity in the water will improve the quality of purification. The results showed that the best salinity was of daily growth rate was 26 ‰ (0.531 ± 0.006), and 29 ‰ (0.514 ± 0.003) was the second best, optimum salinity range was 26 ~ 29 ‰ in S. costatum. The best salinity of T. weissflogii was also 26 ‰ (0.354 ± 0.003), while the growth rate of 23 ‰,26 ‰,29 ‰ treatment was not significantly different, so the optimum range of salinity was between 23 and 29 ‰. The results showed the growth rate of 25 ℃ treatment group was higher than the 20℃. The best growth rate of all treatment in two diatoms was treated with 5000 lux, photoperiod 10L: 14D in 26‰ salinity medium at 25℃. The results showed that the two diatoms could be preserved in Walne medium with 8℃ in the dark more than one month, and avoid stored the algae in declining phase. The concentrated of S. costatum. will die quickly, that was useless in cold-storage method, while the concentrated of T. weissflogii was efficient. The excess nutrients of medium will cause algae death, added to the standard Walne medium is limited. The treatment of S. costatum preserved more than three months , which cultured in 6-7 days at 25℃,that was the most suitable conditions for cold storage.
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Alsaadi, Ahmad S. "The Effect of Non-condensable Gases Removal on Air Gap Membrane Distillation: Experimental and Simulation Studies." Diss., 2014. http://hdl.handle.net/10754/316390.
Full textAbstract:
In the kingdom of Saudi Arabia (KSA), the current seawater desalination technologies are completely relying on burning unsustainable crude oil as their main energy driver. Saudi authorities have realized that the KSA is not going to be protected from the future global energy crisis and have started to set up a plan to diversify its energy resources.
Membrane Distillation (MD) has emerged as an attractive alternative desalination process. It combines advantages from both thermal and membrane-based technologies and holds the potential of being a cost-effective separation process that can utilize low-grade waste heat or renewable energy. MD has four different configurations; among them is Air Gap Membrane Distillation (AGMD) which is the second most commonly tested and the most commercially available pilot-plant design.
AGMD has a stagnant thin layer of air between the membrane and the condensation surface. This layer introduces a mass transfer resistance that makes the process require a large membrane surface area if a large quantity of fresh water is desired.
This dissertation reports on experimental and theoretical work conducted to enhance the AGMD flux by removing non-condensable gases from the module and replacing it with either vacuum, liquid water or porous materials. At first, a mathematical model for AGMD was developed and validated experimentally to create a baseline for improvements that could be achieved after the removal of non-condensable gases. The mathematical model was then modified to simulate the process under vacuum where it showed a flux enhancement that reached 286%. The Water Gap Membrane Distillation (WGMD) configuration improved the flux by almost the same percentage. Since enhancing the flux is expected to increase temperature polarization effects, a theoretical study was conducted on the effect of temperature polarization in a Vacuum Membrane Distillation (VMD) configuration. The study showed that the effect of temperature polarization at small temperature difference (3-7) degree Celsius between the bulk feed and coolant temperatures is significantly high. This may indicate the importance of mitigating the effect of temperature polarization in large scale modules operating at small temperature difference across the membrane. The dissertation concluded with some recommendations for future work.
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Ke, Cheng-Jin, and 柯程晉. "Investigation in Experimental Parameter for scale-up ofAmino-Capped Aniline Trimer and Derived Electroactive Epoxy/Graphene Composite Material Studies on Electrochemical Anticorrosion." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/20961043235093456421.
Full textAbstract:
碩士中原大學
化學研究所
104
This dissertation is mainly focused on two research parts：(1) for the target of mass production of amine-capped aniline trimer (ACAT), several experimental parameters were investigated and tried to effectively increase the yield of ACAT；(2) the as-prepared ACAT with high yield was use to synthesize a series of electroactive epoxy/graphene composite coatings, followed by applied in anticorrosion application. In the first part, one-step oxidative coupling reaction was used to synthesize ACAT. In order to increase the yield of as-prepared ACAT, seven experimental parameters (e.g., different pH at same acid solution, different acid environments, reaction temperature, reaction time, kinds of oxidants, molar ratio of oxidant respect to monomer and concentration of reactive monomer) were investigated. The chemical structure of as-prepared ACAT was characterized by Mass, FT-IR and 1H-NMR spectroscopy. In summary, several conclusions can be drawn. First of all, in the solvent of pure water (i.e., pH = 7) and [oxidant] / [monomer] = 2, the yield of ACAT can be deffectively improve. However, the reaction temperature, reaction time and concentration of monomer used was found no obvious effect to facilitate the yield of ACAT. In this study, the yield of ACAT can be increased from original value of 40.2% to final value of 85.5%. In the second part, the as-prepared ACAT with yield of 85.5% was used to react with dianhydride to prepare a series of electroactive/rGO composite anticorrosion coatings. The corrosion protection performance of cold-rolled steel coupons coated with composites was determined by a series of standard electrochemical corrosion measurements in saline condition. The improvements in corrosion protection of electroactive epoxy resin/rGO composite coatings may be resulted from the following four possible reasons: (1) Reversible redox capability of electroactive epoxy resin leads the formation of densely passive of metal oxide to protect the underlayer metallic substrate； (2) Introducing the graphene platelets into electroactive epoxy coating may effectively increase the length of the diffusion pathways for oxygen and water as well as decrease the permeability of the coating；(3) Electroactive epoxy resin and composite coatings exhibited excellent adhesion capability upon metallic substrate；(4) Introducing the graphene platelets into electroactive epoxy coating surface may also increase the surface hydrophobicity of polymeric coating.