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MICROALGAE HARVESTING IN A MICROFLUIDIC CENTRIFUGAL SEPARATOR FOR ENHANCED BIOFUEL PRODUCTIONUnknown Date (has links)
Among various sources for biofuels, microalgae provide at least three-orders-of-magnitude higher production rate of biodiesel at a given land area than conventional crop-based methods. However, microalgal biodiesel still suffers from significantly lower harvesting efficiency, making such a fuel less competitive. To increase the separation efficiency of microalgae from cultivation solution, an orbital microchannel was utilized that enabled the isolation of biofuel-algae particles from the effluent. The results obtained showed that the separation efficiency in the microfluidic centrifugal separator can be as high as 76% within a quick separation time of 30 seconds. Multiple parameters of algae behaviors and separation techniques such as initial concentration, pH and temperature were studied and manipulated to achieve better efficiencies. It was found that changing these factors altered the separation efficiency by increasing or decreasing flocculation, or “clumping” of the microalgae within the microchannels. The results suggested that an acidic condition would enhance the separation efficiency since in a basic environment, large flocs of microalgae would block and hinder the separation process. Furthermore, a hot temperature solution (around 33 °C) yielded to a higher separation efficiency. The important characteristics of the separator geometry and the infusion rate on algae separation were also very effective in the separation process. This study revealed that there is an opportunity to improve the currently low efficiency of algae separation in centrifugal systems using much smaller designs in size, ensuring a much more efficient algae harvesting. / Includes bibliography. / Thesis (MS)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection
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Řízení separace chemických vzorků dvojicí vysokonapěťových zdrojů / Separation control of chemical solutions by high voltage supply pairZálešák, Jiří January 2008 (has links)
This thesis deal with detailed conception separation control of chemical solutions by high voltage supply pair. In the first part of solving is projected galvanic separation high - voltage supply from control system. Second part deal with on programming control algorithm in PLC AMiRiS99. Third part deal with communication PC – PLC and conception finished aplication.
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Popis elektroforetických separačních systémů, využití systémových píků k charakterizaci vlastností surfaktantů a optimalizace složitějších systémů pomocí modelu LFER / Characterization of electrophoretic separation systems,utilization of system peaks for determination of surfactant properties and optimalization of complex separation systems by the LFER modelLokajová, Jana January 2008 (has links)
Conclusions o We have developď new method for CMC determination that is based on the measurementsof sysrem peaks eigenmobilities in capiiluy "t*o"oo"r*tr. The proposed method is moreprecise and eliminates specific systematic errors .o.*'n* when using some s*ndaťdmethods. The proposed method has U".n opti*i""a "o^ia,sysrcm peaks. ..Ý9 .r4. uE'tl UP.lmzeo considering intensities (amplitudes) of o The implementation of mice description ", ",".o".#'ÍÍ.',11Tffi :: jlTl.Ti#'ff ffiTr,"JT::,l:systems. Simulation prognrms curÍently allow user. to cď"ulate system eigenmobilities andeven to optimize the micellar separation systen. We h;\ *:ffi J:ffi.;: oÍ extended simulation o.o,*,",.u".il.;:T"T1'ffi ' ffill: We have clarified the mobi strength, which "uu,", .pri..ll,l?.jln.fi.r::ř""".J:"# peak due to the BGES ionic additional peak has "oo.a,.o in the electrophe.oror, ,oo**"r' As a consequence an :::::::::'*":u.'*..in.*oo.". identifi cation ", i"*,,.,"'ť"i:TT. *i:ajff:oeen possible using rhe set of different derecrion waveilil:" capirrary zone electrophoresis has been used to revear a structure and charge of nanoparticresin the recentry synthesized bulky porymer micelres ,n-'ltt".*, pH regions and to t3 characterize the effect of the PvP fraction added to PS.PMA on the final structure. ouÍ results have confirmed that...
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Natural Gas Sweetening by Ultra-Microporous Polyimides MembranesAlghunaimi, Fahd 05 1900 (has links)
Most natural gas fields in Saudi Arabia contain around 10 mol.% carbon dioxide. The present technology to remove carbon dioxide is performed by chemical absorption, which has many drawbacks. Alternatively, membrane-based gas separation technology has attracted great interest in recent years due to: (i) simple modular design, (ii) potential cost effectiveness, (iii) ease of scale-up, and (iv) environmental friendliness. The state-of-the-art membrane materials for natural gas sweetening are glassy cellulose acetate and polyimide, which were introduced in the 1980s. In the near future, the kingdom is planning to boost its production of natural gas for power generation and increase the feedstock for new petrochemical plants. Therefore, the kingdom and worldwide market has an urgent need for better membrane materials to remove carbon dioxide from raw natural gas.
The focus of this dissertation was to design new polyimide membrane materials for CO2/CH4 separation exhibiting high permeability and high selectivity relative to the standard commercial materials tested under realistic mixed-gas feed conditions. Furthermore, this study provided a fundamental understanding of structure/gas transport property relationships of triptycene-based PIM-polyimides. Optimally designed intrinsically microporous polyimide (PIM-PIs) membranes in this work exhibited drastically increased CO2/CH4 selectivities of up to ~75. In addition, a novel triptycene-based hydroxyl-containing polyimide (TDA1-APAF) showed 5-fold higher permeabilities over benchmark commercial materials such as cellulose acetate. Furthermore, this polyimide had a N2/CH4 selectivity of 2.3, thereby making it possible to simultaneously treat CO2- and N2-contaminated natural gas. Also, TDA1-APAF showed a CO2 permeability of 21 Barrer under binary 1:1 CO2/CH4 mixed-gas feed with a selectivity of 72 at a partial CO2 pressure of 10 bar which are significantly better than cellulose triacetate. These results suggest that TDA1-APAF polyimide is an excellent candidate membrane material for removal of CO2 and N2 from natural gas. Moreover, based on the collected data for CO2/CH4 mixed-gas experiments from this work and previously published reports, a new mixed-gas 2017 CO2/CH4 permeability/selectivity upper bound curve was initiated to reflect the actual performance including plasticization phenomena at high feed pressure and 10 bar CO2 partial pressure to simulate the real conditions of the wellhead pressure.
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Selective CO Adsorption Separation from CO2 via Cu-modified AdsorbentsAbbassi, Maria 18 May 2021 (has links)
CO2 capture and conversion appears to be a prominent solution to mitigate greenhouse gas
emissions (GHG) and global warming issue. Among different CO2 conversion approaches,
CO2 hydrogenation via reverse water gas shift (RWGS) reaction is one of the most promising
technology to convert CO2 to CO. Subsequently, CO is transformed to value added chemicals
or liquid fuels. To improve the overall CO2 conversion for RWGS reaction, product separation
and recycling is being proposed.
In this research, adsorption separation technology has been explored to selectively separate
CO from CO2 in RWGS using pressure swing adsorption (PSA) process. To investigate the
adsorption capacity and selectivity of CO, different porous materials have been identified for
CO separation. In this research, activated carbons, ordered mesoporous silica, and metal
organic framework materials were studied. Equilibrium isotherms of CO and CO2 were
measured in a gravimetric system at a temperature of 25 °C for pressures up to 20 bar.
Preliminary adsorption isotherm results had shown an insufficient CO uptake and low
selectivity level compared to CO2, thus not justifying their application for CO separation.
Herein, to improve the CO adsorption capacity and selectivity, Cu-based adsorbents were
developed using copper (II) chloride (CuCl2) as a precursor to synthesize six different
adsorbents. The adsorbents were prepared using two different synthesis methods; the modified
polyol method for reduction and nanoparticle deposition of Cu (I) ions, and thermal monolayer
auto-dispersion method. Furthermore, different copper (II) loadings were investigated to
determine the monolayer dispersion capacity of CuCl2 on the support.
The modified adsorbents by copper salt exhibited significantly high CO uptake with large
CO/CO2 selectivity, reversing the results obtained before adsorbent modification. Thus, Cubased adsorbents are promising materials for CO separation and recovery from a gaseous mixture containing CO2.
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Tissue Extraction and High-Performance Liquid Chromatographic Determination of Ketoprofen EnantiomersPanus, Peter C., Tober-Meyer, Brunhilde, Ferslew, Kenneth E. 13 February 1998 (has links)
Local transcutaneous delivery of non-steroidal anti-inflammatory drugs avoids gastrointestinal side effects and concentrates drugs in the intended tissues. An extraction and HPLC method was developed for ketoprofen in skin, fascia and muscle. Tissue samples were homogenized in NaHCO3. After methylene chloride removal of lipids, the aqueous layer was acidified with HCl and back extracted into isooctane/isopropanol. Ketoprofen was derivatized with ethylchloroformate/S-(-)-α-phenylethylamine in triethylamine, then detected by HPLC. Ketoprofen recovery was linear (1-33 μg/g) and was detected in these tissues following in vivo cathodic iontophoresis (160 mA*min). This represents the first non-radioactive method for determination of ketoprofen in tissues following transcutaneous iontophoresis.
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Benefits of thoracic epidural analgesia in patients undergoing an open posterior component separation for abdominal herniorrhaphySellers, Austin 13 July 2017 (has links)
INTRODUCTION: The implementation of open posterior component separation (PCS) surgery has led to improved outcomes for complex hernias. While the PCS technique has been shown to decrease recurrence rates, and provide a feasible option to repair hernias in nontraditional locations, there is still significant postoperative pain associated with the laparotomy and extensive abdominal wall manipulation. Systemic opioids and thoracic epidural analgesia (TEA) are both commonly utilized, either together or independently, as postoperative analgesic regimens. The benefits of TEA have been studied following a variety of surgeries, however to date no study has been performed to investigate its efficacy in this particular surgery. The aim of this study is to evaluate the benefits of TEA following open PCS. We hypothesized that the incorporation of TEA in a patients postoperative analgesic regimen would show an advantage in time to bowel recovery.
METHODS: An electronic medical record query was done to identify patients who had undergone an open PCS. Once this list was compiled, a retrospective chart review was performed and patients receiving TEA (either alone or combined with systemic opioids) were compared to patients receiving only systemic opioids. The primary endpoint compared time to resumption of a full diet, given by the patients postoperative day (POD). Secondarily, time to resumption of a liquid diet, postoperative length of stay (LOS), intensive care unit (ICU) admission rate, ICU LOS, and rates of several postoperative complications were all recorded and compared. A post-hoc analysis was also performed using the same endpoints. This analysis compared cohorts of patients receiving TEA and avoiding all systemic opioids, to patients who received systemic opioids (whether alone or combined with TEA).
RESULTS: Based on inclusion parameters, 101 patients met criteria for analysis. In the initial analysis, 62 patients received TEA with or without systemic opioids, and 39 patients received only systemic opioids. In comparing these groups, there was no statistically significant difference in time to full diet (TEA 2.6 ± 1.7 vs Systemic opioids 3.1 ± 2.1 [mean POD ± SD]; P=0.21). In addition, no differences were found in the secondary outcomes of time to liquid diet, ICU admission, ICU LOS, or postoperative complications. In the post-hoc analysis, the 37 patients that received only TEA, were compared against 64 patients that received systemic opioids (either with or without TEA). In this comparison, the group receiving only TEA was found to have a statically shorter time to bowel recovery compared to patients receiving systemic opioids (TEA alone 2.2 ± 1.0 vs Systemic opioids 3.2 ± 2.2, P=0.0033). This subgroup (TEA only) also showed statically shorter time to liquid diet and a decreased postoperative LOS.
CONCLUSION: For patients undergoing an open PCS, the inclusion of TEA in the postoperative analgesic regimen did not shorten return of bowel function. However, when TEA was utilized and systemic opioids were avoided, time to bowel recovery and hospital LOS were both significantly shortened.
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Codage réseau pour des applications multimédias avancées / Network coding for advanced video applicationsNemoianu, Irina-Delia 20 June 2013 (has links)
Le codage réseau est un paradigme qui permet une utilisation efficace du réseau. Il maximise le débit dans un réseau multi-saut en multicast et réduit le retard. Dans cette thèse, nous concentrons notre attention sur l’intégration du codage réseau aux applications multimédias, et en particulier aux systèmes avancès qui fournissent un service vidéo amélioré pour les utilisateurs. Nos contributions concernent plusieurs scénarios : un cadre de fonctions efficace pour la transmission de flux en directe qui utilise à la fois le codage réseau et le codage par description multiple, une nouvelle stratégie de transmission pour les réseaux sans fil avec perte qui garantit un compromis entre la résilience vis-à-vis des perte et la reduction du retard sur la base d’une optimisation débit-distorsion de l'ordonnancement des images vidéo, que nous avons également étendu au cas du streaming multi-vue interactive, un système replication sociale distribuée qui, en utilisant le réseau codage en relation et la connaissance des préférences des utilisateurs en termes de vue, est en mesure de sélectionner un schéma de réplication capable de fournir une vidéo de haute qualité en accédant seulement aux autres membres du groupe social, sans encourir le coût d’accès associé à une connexion à un serveur central et sans échanger des larges tables de métadonnées pour tenir trace des éléments répliqués, et, finalement, une étude sur l’utilisation de techniques de séparation aveugle de source -pour réduire l’overhead encouru par les schémas de codage réseau- basé sur des techniques de détection d’erreur telles que le codage de parité et la génération de message digest. / Network coding is a paradigm that allows an efficient use of the capacity of communication networks. It maximizes the throughput in a multi-hop multicast communication and reduces the delay. In this thesis, we focus our attention to the integration of the network coding framework to multimedia applications, and in particular to advanced systems that provide enhanced video services to the users. Our contributions concern several instances of advanced multimedia communications: an efficient framework for transmission of a live stream making joint use of network coding and multiple description coding; a novel transmission strategy for lossy wireless networks that guarantees a trade-off between loss resilience and short delay based on a rate-distortion optimized scheduling of the video frames, that we also extended to the case of interactive multi-view streaming; a distributed social caching system that, using network coding in conjunction with the knowledge of the users' preferences in terms of views, is able to select a replication scheme such that to provide a high video quality by accessing only other members of the social group without incurring the access cost associated with a connection to a central server and without exchanging large tables of metadata to keep track of the replicated parts; and, finally, a study on using blind source separation techniques to reduce the overhead incurred by network coding schemes based on error-detecting techniques such as parity coding and message digest generation. All our contributions are aimed at using network coding to enhance the quality of video transmission in terms of distortion and delay perceived
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Stabilization of Lactate Dehydrogenase and Peptide Separation via Electrophoresis Using A Pluronic PolymerChen, Yudan 27 July 2020 (has links)
No description available.
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Induction and production of specific extracellular lipases from selected microorganismsNgom, Marie Odile. January 2000 (has links)
No description available.
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