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A typical electrochemistry experiment using a three-electrode detection cell requires a large volume of analyte to submerse the electrodes. In this experiment the possibility of detecting smaller volumes of analyte on a woven polyester fiber (shoelace) using chronoamperometry is investigated. The goal of the experiment is to separate, and then detect a mixture of three phenolic acids: ascorbic, caffeic, and vanillic acid. It is determined that the best method for separation of the three compounds is through column chromatography with a Sephadex stationary phase. Once separated, each analyte is presented to the electrodes by the polyester fiber. Using this developed method, the separation efficiency and the detection limits for the three compounds are determined.

With the continuous development of the industry, oil spill accidents occur frequently. Oil/water separation materials are considered to be a major choice for the treatment of oily wastewater due to their flexible operation and low cost. Cotton fabrics are low-cost and environmentally friendly, which are used as substrates to prepare oil/water separation materials with quite competitive in the market. A large number of oil/water separation cotton fabrics with excellent properties have been frequently reported in recent decades. On the other hand, since the service life of these oil/water separation cotton fabrics is closely related to the thin layer covered on the surface, so in order to improve the practical applicability, substances such as dopamine and plant polyphenols that improve the adhesion of the thin layer to the surface of the material are introduced into the preparation process of these materials. On this basis, the research progress of super-hydrophobic cotton fabrics, super-hydrophilic/underwater super-oleophobic cotton fabrics, super durable oil/water separation cotton fabrics and intelligent response to oil/water separation fabric in recent years are reviewed, as well as their applications in the field of oil/water separation, The authors gratefully acknowledge the financial support of Science and Technology Project of Keqiao District, Shaoxing City (Grant No. 2022JBGS111), and the International Science and Technology Cooperation Project of Shaoxing University (Grant No. 2019LGGH1004), Postprint (author's final draft)

Producción Científica, Forward osmosis (FO) has attracted special attention in water and wastewater treatment due to its role in addressing the challenges of water scarcity and contamination. The presence of emerging contaminants in water sources raises concerns regarding their environmental and public health impacts. Conventional wastewater treatment methods cannot effectively remove these contaminants; thus, innovative approaches are required. FO membranes offer a promising solution for wastewater treatment and removal of the contaminants in wastewater. Several factors influence the performance of FO processes, including concentration polarization, membrane fouling, draw solute selection, and reverse salt flux. Therefore, understanding and optimizing these factors are crucial aspects for improving the efficiency and sustainability of the FO process. This review stresses the need for research to explore the potential and challenges of FO membranes to meet municipal wastewater treatment requirements, to optimize the process, to reduce energy consumption, and to promote scalability for potential industrial applications. In conclusion, FO shows promising performance for wastewater treatment, dealing with emerging pollutants and contributing to sustainable practices. By improving the FO process and addressing its challenges, we could contribute to improve the availability of water resources amid the global water scarcity concerns, as well as contribute to the circular economy., Junta de Castilla y León y Fondo Europeo de Desarrollo Regional (FEDER) - (grant CL-EI-2021-07, VA088G19, UIC 082, and UIC 334), Ministerio de Ciencia e Innovación/Agencia Estatal de Investigación (AEI)/10.13039/501100011033 - (project PID2019-109403RB-C21)

Producción Científica, The enantiomeric separation of antifungal compounds is an arduous task in pharmaceutical and biomedical fields due to the different properties that each diastereoisomer presents. The enantioseparation of a group of fungicides (sulconazole, bifonazole, triadimefon and triadimenol) using supercritical fluid chromatography was achieved in this work. For this goal, four different chiral columns based on polysaccharide derivatives, as well as the effect of different chromatographic parameters such as temperature, type and percentage of organic modifier (methanol, ethanol and isopropanol), were thoroughly investigated. The inversion of the elution order of enantiomers as a result of a change in the stationary phase or organic modifier was also evaluated by employing a circular dichroism detector. The best separation conditions, in terms of the enantioresolution and analysis time, were obtained with the Lux® Cellulose-2 column using isopropanol as the organic modifier.

Crystallization is an alternative separation and purification technique to conventional chromatography for proteins due to specific characteristics, such as good scalability, low cost, and the attainable stability of the crystalline products. However, protein crystallization often suffers from long batch time due to the slow crystallization kinetics. Furthermore, protein crystallization is conventionally conducted in the batch mode of operation, which has potential disadvantages compared to continuous operation. These challenges of protein crystallization are addressed in this thesis by employing process intensification principles. The work presented in this thesis will focus on two typical process intensification domains, i.e., the space and time domains involving equipment structurization and continuous operation. 3D printing is used as a tool to achieve process intensification through structurization, because of its ability for rapid fabrication of customized process equipment with complex geometries. Novel crystallizer types and process configurations are investigated with the aid of 3D printing as the fabrication technique. First, a workflow for the fabrication of crystallizers with 3D printing is presented. The workflow aids in the selection of appropriate 3D printing techniques and suitable materials for the fabrication of custom-designed crystallizer. Furthermore, the designs for the crystallizers used in this thesis are developed based on models or heuristics. These designs can be a platform or template for other crystallizers with geometric similarities and can also be the start of a library of crystallizers that can be customized and fabricated as required. 3D printing has found limited applications in the fabrication of equipment for separation processes, including crystallization, despite the extensive utilization in, for example, reaction engineering. The workflow aims to facilitate the adoption of 3D printing as a tool to achieve process intensificati

Purpose: The purpose of this study is to solve the inverse homogenization problem, or so-called material design problem, using the topological derivative concept. Design/methodology/approach : The optimal topology is obtained through a relaxed formulation of the problem by replacing the characteristic function with a continuous design variable, so-called density variable. The constitutive tensor is then parametrized with the density variable through an analytical interpolation scheme that is based on the topological derivative concept. The intermediate values that may appear in the optimal topologies are removed by penalizing the perimeter functional. Findings: The optimization process benefits from the intermediate values that provide the proposed method reaching to solutions that the topological derivative had not been able to find before. In addition, the presented theory opens the path to propose a new framework of research where the topological derivative uses classical optimization algorithms. Originality/value: The proposed methodology allows us to use the topological derivative concept for solving the inverse homogenization problem and to fulfil the optimality conditions of the problem with the use of classical optimization algorithms. The authors solved several material design examples through a projected gradient algorithm to show the advantages of the proposed method., This research was partially supported by Serra Húnter Research Program (Spain), PID-UTN (Research and Development Program of the National Technological University, Argentina) and CONICET (National Council for Scientific and Technical Research, Argentina). The supports of these agencies are gratefully acknowledged., Peer Reviewed, Postprint (author's final draft)

Summary: 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., 2021, Includes bibliography., Degree granted: Thesis (MS)--Florida Atlantic University, 2021., Collection: FAU Electronic Theses and Dissertations Collection

This paper proposes pre-beneficiation studies by air jigs of the coal layers from a Moatize coal deposit. Pre-beneficiation, also called destoning, removes tailings before the beneficiation plant. The air jigs operate in the same granulometric size range as the heavy-media cyclones (HMCs) that are installed in the preparation plant. With the destoning, the heavy-media circuit operates with a lower coal feed and higher organic matter contents, increasing its cutting efficiency and lowering operational costs. The use of air jigs reduces the total water consumption in the plant, which is especially important for the region where the plant is installed, aswater is particularly scarce. Four coal layers of the Moatize coal deposit were studied, which are currentlyexploited in the mine. As main results of the study, it is possible to say that the concentration of lights (feed of the preparation plant) and heavies (waste fraction) in air jigs can be carried out with reasonable efficiencies for all coal layers studied, making air jigs a feasible option for coal destoning., This research was funded by Instituto Tecnológico Vale (ITV) Ouro Preto, Brazil., Peer Reviewed, Postprint (published version)

© 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, This work aims to evaluate the use of the air jigging technique, a density-based separation technology commonly applied in mineral processing, to upgrade the quality of mixtures (density and geometric properties) that represents the typical composition of construction and demolition waste (CDW) produced in Brazil. In this sense, tests involving the variation of the main operational parameters of jigging (bed expansion rate, pulsation frequency and jigging time) were carried out aiming to find those which provided the best recycled aggregates quality after processing. Also, fines and dust emissions generation during jigging were measured in order to estimate their potential impacts on human health and environment. The results showed that the air jigging process is adequate to improve the quality of CDW by increasing the concrete concentration in the dense product. The use of high bed expansion rates showed to be of major importance to decrease the content of ceramic aggregates in the dense product, allowing obtaining products richer in concrete. Also, the measured properties of the obtained aggregates (size distribution, shape, etc) met the usual standards required for natural aggregates. Finally, material losses and dust emissions generated were negligible in comparison to the total mass processed, although special attention must be given to safety measures due the presence of inhalable particles (<10 µm)., Peer Reviewed, Postprint (author's final draft)

This work demonstrates the effective use of automatic sensor-based sorting technology as a viable separation method for rare earth element (REE) rich ores composed primarily of xenotime minerals with gagarinite-(Y) and fluocerite-(Ce, La) inclusions. A dual energy X-ray transmission (DE-XRT) sensor affinity was used to evaluate forty-two heavy rare earth element (HREE) ore grab samples from the Madeira deposit. These samples and separated products were scanned by the sensor under many operating parameters. Subsequent analyses, including petrographic and multi-element chemical analyses were performed on the grab samples. Specific mass tests were also compared with energy attenuation curves from the sensor, which correlated strongly with every concentration stage – the highest achieved density being 3.01 g/cm3. The best estimated HREE recovery from laboratory-scale sorting of the samples identified by the sensor was effectively 100%, however this occurred in conjunction with a mass recovery equal to 97% of the feed. Such results are expected knowing that the sample method was not entirely representative. Ongoing research into automatic sorting technology for the upgrading of Brazilian ores is being performed by the Federal University of Rio Grande do Sul (UFRGS), Brazil., Peer Reviewed, Postprint (author's final draft)

A better understanding of ion-transport mechanisms requires separate information on the equilibrium (partitioning) and kinetic (diffusivity) properties of the membranes with respect to ions. This work presents a novel non-stationary-diffusion method to determine salt diffusion and partitioning coefficients under (quasi)-linear conditions of relatively small concentration differences. An ion-exchange membrane supported by a relatively thick coarse-porous support (glass frit) is placed in a two-compartment stirred cell. The salt concentration in one compartment is kept stationary during the measurement whereas in the other compartment, the initial solution is rapidly replaced by a solution of different concentration. As a result, there is a time-dependent electrical response due to a progressive redistribution of applied concentration difference between the membrane and the porous support and the different ion perm-selectivities of those media. A mathematical model is developed to interpret the data. The rate of signal relaxation is primarily controlled by the diffusion permeability of the membrane but is also affected by the salt partitioning. In addition, osmotic trans-membrane volume transfer has a significant impact on the relaxation process, so it needs to be taken into account. The osmotic permeability has been determined in separate measurements. Systematic studies have been carried out at various NaCl concentrations with Nafion 120 and type 10 Fujifilm ion-exchange membranes. The results obtained for Nafion 120 are in agreement with the literature data. Well-established techniques have also been used to validate the novel approach. This allows for a relatively simple determination of salt permeability and partitioning coefficient in addition to the ion perm-selectivity, which is the only parameter available from the conventional measurements of stationary membrane potential, Peer Reviewed, Postprint (author's final draft)

En el presente trabajo se realiza un estudio para determinar la idoneidad de utilizar técnicas biológicas para el proceso de absorción y oxidación de monóxido de nitrógeno (NO) a nitrato y/o nitrito.Por tanto, se diseñó y construyó un biofiltro percolador(BTF) a escala laboratorio utilizando un material de empaque aleatorio (anillos Pall de PP) y a partir de una estructura cilíndrica de policloruro de vinilo (PVC) con una altura total de 96,5 cm, con el fin de realizar ensayos de oxidación biológica de NO.Este sistema se complementó con una monitorización on-liney regulación automática de las variables del procesode pH, temperatura y NO.Para realizar el seguimiento on-line de la fase gas y off-line de la concentración de especies iónicas en solución ylas pruebas preliminares de absorción/oxidación se gestionó la operación del BTF durante un período total de 59 días. En los primeros 19 días (Periodo I) se alimentó una concentración de contaminante entre380 –420 ppmvdeNO y se controlóel equipo para que estuviera a una temperatura ambiente y pH neutro.ElBTF operó con unos valores de EBRT de120 s y TLVde 10 m·h-1 . En este periodo, se evidenció que había una influencia inhibidora porla presencia de NH4Cl del mediomineral.Entrelos días 20 y29 (periodo II) se siguió alimentandola mismaconcentración de NO del periodo, se eliminó el cloruro de amonio (NH4Cl) del medio mineraly se disminuyó el valor de EBRT a 100 s.En este periodo se encontró que a pesar de que el NO!"sufría una caída importante en su concentración, el NO#"sufría un descenso hasta el día 25sin ser considerable, alcanzando un valor de 1195 ppm, y vuelve a haber un ascenso, el día 29 (1674 ppm).Por último, en el periodo III que corresponde desde el día 30 al 59 se dejo de alimentar concentración de NO, en cambio se alimentó nitrito de sodio (NaNO2 ) para que hubiera reproducción de las bacterias nitrificantes. En este periodo hubieron los mismo parámetros operaciones que en el periodo II. En este periodo se en

Ion passage through ion-exchange membranes is vital in electrodialysis desalination, batteries and fuel cells, and water splitting. Simplified models of ion transport through such membranes frequently assume complete exclusion of co-ions (ions with the same sign of charge as the fixed charge in the membrane) from the membrane. However, a second assumption of constant counterion electrochemical potentials across the membrane leads to simple analytical expressions for ion fluxes and transmembrane potentials. Moreover, linear corrections to account for a small membrane electrical resistance yield analytical expressions with a wider applicability. For bi-ionic potential measurements and current-induced concentration polarization at low salt concentrations, these analytical solutions match the fluxes and potentials obtained numerically without the limiting assumptions. This gives confidence in both the limiting assumptions (under appropriate conditions) and the numerical solutions. At low ion concentrations, the analytical solutions may enable rapid characterization of membrane coatings or boundary layers in solution, and such boundary layers are important in many applications of ion-exchange membranes. In fact, the assumption of complete co-ion exclusion is sometimes more limiting than the constraint of constant electrochemical potentials of counterions across the membrane. Remarkably, this limiting case readily yields the ion accumulation and depletion regions above “ion-exchange patches” that reside beneath a solution with an applied electric field. Such regions are important for sample preconcentration in microfluidic devices, Peer Reviewed, Postprint (author's final draft)

Una empresa de la regió produeix una gran quantitat d'encenalls ( 30 tones/mes) de la qual no treuen cap rendiment. L'objectiu del projecte és recuperar l'oli de tall i intentar separar els diferents tipus de metalls per poder-ne treure un rendiment econòmic., Outgoing

This work shows the results of the experimental study made with an experimental hydrocyclone used in the mineral processing laboratory, EPSEM (Manresa, Barcelona). The study elaborated shows the efficiency curves and cut size of different experiments, changing initial parameters and conditions in order to collect data of the hydrocyclone behaviour. Using a homogeneous material coming from the Barruecopardo mine tailing in small particle size distribution as a slurry base. The data from both outputs of the hydrocyclone and feed have been evaluated and used for the efficiency curves results. Several comparisons between theoretical parameters and the real ones have been done in order to make a previous statement in its behaviour and performance. Once the experimental phase is done, deep comparison between almost similar cases intentionally simulated have been done and discussed the overall of the experiments.

Descripció del recurs: 5 de febrer de 2018, La biotecnología moderna se basa en la ingeniería genética, pero sin los procesos posteriores de separación y purificación a escala de producción, ningún bioproducto puede llegar a ser una realidad comercial. Este libro es el resultado de la experiencia del autor en la docencia y el desarrollo experimental de procesos en la industria y la universidad. Se estudian en este libro los procesos de filtración, disrupción celular, centrifugación, precipitación, floculación, extracción, adsorción/desorción, cromatografía, cristalización y secado aplicados a las industrias biotecnológicas, haciendo énfasis en los fundamentos y en el cambio de escala., 1

The issue of the abundance of waste printed circuit boards (WPCB) is a worldwide dilemma due to the fast upgrading of manufacturing technology and the short life span of electronic devices. Traditional treatment methods are facing the challenge of public concerns since they fail to solve the toxic emission problem as well as the high construction / operation cost. Nevertheless the recycling of WPCB achieved the recovery of the metallic fraction of WPCB; they failed to provide a solution for the non-metallic fraction (NMF) of WPCB and most of them have a negative profit. A lot of studies have been done based of the reuse of the NMF, but majority of them still were proved to be invalid of remedying the cost of metallic faction recycling. Currently, the chemical composition and framework structure of the NMF imply a possibility of utilizing the NMF as a precursor for aluminosilicate adsorbent production. In this study, the NMF was used as the feedstock of an adsorbent production process and it showed superior heavy metal uptake capacity after the surface functionalization. In the first phase of this study, the reaction parameters of the production process were studied and optimized to provide an optimum condition of material production. The reaction parameters including reaction temperature, impregnation ratio and reaction time were investigated and the results showed that the optimum condition was 300˚C, impregnation ratio of 2 and 1 h reaction time. Further textural properties and surface characterization proved as-prepared sample have the well-developed structure as well as the high density of surface functional group. After that, it is proved that quenching technology is also capable to further improve the surface properties of the material by prevent the unwanted side reaction during the cooling process. The batch adsorption tests proved that quenched sample had even higher heavy metal uptake capacities. In the second phase of this study, the environmental emissio

Resuspension is an important phenomenon in many industrial and environmental processes. Previous studies of the resuspension of liquid droplets or solid particles have shown a deviation from actual situations. It is suspected that lack of consideration of the influences fine particles was as the major factor leading to the deviation. Many engineering or environmental processes, such as the spraying of pesticide and paint, disease transmission and filtration, involve not only a single type of particles. Understanding the detachment behavior can help us improve those engineering processes and reduce our exposure to air pollutants. This research studies the detachment behaviors of two common cases by a centrifugal method – Firstly, solid particles detachment from a dusty surface; secondly, droplets detachment with a fluid with nanoparticles suspended in it. For the first scenario, the detachment behavior of micron-sized polyethylene (PE) particles with the influence of fine dust particles on a surface was studied. The dusty surface was produced by settling Arizona test dust (ATD) on a cleaned Poly(methyl methacrylate) (PMMA) substrate by gravitational settling inside a deposition chamber. It was found that the adhesive force of PE particles decreased significantly with the increase of dust density. For the second scenario, the influence of the ultrafine particles suspension in micrometer-sized droplets was investigated by using a pure glycerol-water (pure fluid) and that with the addition of nanoparticles (nanofluid) on three different surfaces materials. It is found that nanofluid droplets detach by portion under normal force for all the substrate materials, and for tangential force, the droplets detach completely if the exerted force is sufficiently large. The threshold values are material dependent. The addition of nanoparticles results in a higher adhesive force when compared to the droplets of pure fluid within the same size range.

Se pretende realizar la síntesis de partículas magnéticas de ferritas de hierro micro y/o nanoestructuradas a través del proceso de molienda mecánica de alta energía, siguiendo un diseño estadístico de experimentos factorial fraccionado y posteriormente caracterizar las partículas obtenidas por medio de diferentes técnicas estructurales y magnéticas tales como: Difracción de Rayos X (DRX), Espectroscopia Infrarroja por Transformada de Fourier (FTIR), Microscopia Electrónica de Transmisión (TEM), Espectroscopia Mössbauer de Transmisión a temperatura ambiente (TMS) y Magnetometría de Muestra Vibrante (VSM) -- Finalmente se realizara un ensayo con estas partículas, consistente en depositarlas en una solución contaminada con iones de mercurio divalente Hg2+ en una concentración conocida, para evaluar el grado de inmovilización de este catión de metal pesado por las partículas magnéticas -- Con el proyecto se pretende buscar una ruta de síntesis de partículas magnéticas limpia y reproducible que puedan ser utilizadas en aplicaciones tecnológicas y ambientales -- Se pretende realizar la síntesis de partículas magnéticas de ferritas de hierro micro y/o nanoestructuradas a través del proceso de molienda mecánica de alta energía, siguiendo un diseño estadístico de experimentos factorial fraccionado y posteriormente caracterizar las partículas obtenidas por medio de diferentes técnicas estructurales y magnéticas tales como: Difracción de Rayos X (DRX), Espectroscopia Infrarroja por Transformada de Fourier (FTIR), Microscopía Electrónica de Transmisión (TEM), Espectroscopia Mössbauer de Transmisión a temperatura ambiente (TMS) y Magnetometría de Muestra Vibrante (VSM) -- Finalmente se realizara un ensayo con estas partículas, consistente en depositarlas en una solución contaminada con iones de mercurio divalente Hg2+ en una concentración conocida, para evaluar el grado de inmovilización de este catión de metal pesado por las partículas magnéticas -- Con el proyecto se pretende

Descripció del recurs: 6 de febrer de 2017, Aquest llibre és el resultat de l’experiència de l’autor en la docència i el desenvolupament experimental de processos, a la indústria química a diferents empreses i universitats. La biotecnologia moderna es basa en la genètica molecular, però, sense els processos posteriors de separació i purificació a escala de producció, cap bioproducte no pot ser una realitat comercial. Partint del bioreactor, s’estudien en aquest llibre: la filtració, la disrupció cel·lular, la centrifugació, la precipitació, la floculació, l’extracció LL, la adsorció/desorció, la cromatografia, la ultrafiltració/diafiltració, a més de la cristal.lització i l’assecatge, aplicats a la biotecnologia, fent èmfasi en el canvi d’escala en cadascún dels processos., 2

The main source of ammonia in sewage originates from human urine, which typically contributes around 80% of the total nitrogen with only 1% of the total sewage volume. Therefore, decentralized treatment of source-separated urine could be a potential solution to remove nitrogen more efficiently through onsite urine nitrification and in-sewer denitrification than the centralized biological nitrogen removal (BNR) treatment, in a densely populated city like Hong Kong. Achieving effective nitrification of urine at high loading rate with high total ammonia nitrogen (TAN) concentration is the key issue to realize the concept above. Therefore, in this study, a lab-scale hydrostatically pressurized nitrifying bioreactor for source-separated urine nitrification was developed under 7 bars of pressure, which is to simulate natural pressurization condition if such a reactor is to be attached to the façade of a high-rise building, typically 200-400 m high, in Hong Kong. Such a high pressure may result in super-saturation of oxygen in the liquid phase, which could efficiently promote nitrification with high strength of ammonia in the influent. Incomplete ammonia oxidation was observed with a nitrification potential of 99.7% of the influent ammonia while the daily loading rate at around 1.0 kg-TN m-3d-1 was achieved in this novel pressurized bioreactor. Besides, pressure promoted the formation of nitrifying granules providing an efficient liquid-solid separation for space saving. The proposed technology would provide a possible compact onsite urine nitrification system for potential application in Hong Kong. Keywords: pressurized bioreactor; source-separated urine; nitrification; nitrifying granule.

Membrane fouling is a fatal disadvantage hindering the application of membrane separation technology, which decreases permeate flux and shortens membrane service life. This research aims to solve this problem by combining membrane separation technology with external electricity through electrophoretic or electro-oxidation effect. The Magnéli titanium sub-oxide Ti4O7, with robust physical properties and high electrical conductivity, was employed to modify the Al2O3 ceramic membrane to make a novel composite material. The Ti4O7 phase was obtained by dip-coating a TiO2 layer followed by chemical reduction at 1050℃ in H2 atmosphere. The fabricated Ti4O7 layer exhibited a conductivity of over 200 S·cm-1 with particle size of 200 - 300 nm, average pore diameter of 350 nm and water contact angle of 0°. The antifouling performance of the prepared tubular Ti4O7/Al2O3 membrane was evaluated through a home-made cross-flow electricity-assisted membrane filtration (EAF) module where the prepared membrane element served as both the electrode(s) and the filtration media. Two types of electrode configurations were explored for the design of EAF module, namely membrane-wire and membrane-membrane electrode configurations. For the former configuration, electricity was connected between the inner Ti4O7 layer and a wire electrode. For the latter, the inner and outer modified Ti4O7 layers served as electrodes. The filtration performance using the designed EAF module was first evaluated for the treatment of emulsified oily wastewater. The system was further examined using two other typical feed solutions that are known to foul easily, humic acid (HA) and whey proteins. It was found out that the membrane-wire electrode configuration was more effective, especially when electrophoresis

Descripció del recurs: 3 de setembre de 2015, Aquest llibre és el resultat de l’experiencia de l’autor en la docencia i el desenvolupament experimental de processos, a la indústria química a diferents empreses i universitats. La biotecnologia moderna es basa en la genètica molecular, pero, sense els procesos posteriors de separació i purificació a escala de producció, cap bioproducte pot ser una realitat comercial. Partint del bioreactor, s’estudien en aquest llibre: la filtració, disrupció cel·lular, centrifugació, precipitació, floculació, extracció LL, adsorció/desorció, cromatografia, ultrafiltració/diafiltració, a més de cristal. lització i assecatge, aplicats a la biotecnologia, fent èmfasi en el canvi d’escala en cadascún dels processos.

In this thesis an idea of oil/water separation in microfluidics was proposed and being demonstrated. Inspired by gravity differential separation of oily water, water droplets separation from a continuous oil flow using co-flow approach was achieved. Oil/water mixture was simulated by orderly spaced water droplets in an oil flow, by co-flowing with another water flow, water droplets was extracted from the oil flow and merged into the water flow, resulting two pure oil and water flows co-flowing. It was thought that the extraction of water droplet from oil was challenging, however initial trials showed that it is magnificently reliable; the obstacle lies in separating the two co-flowing pure flows. Therefore, channel geometries and hydrophobicity of the channel wall were varied to optimize the separation of the two flows. Results show that a simple T-junction without chemical modification on channel wall attained the best performance among other geometries and chemically modified surfaces. This separation method can be generalized to any two immiscible liquids as well. Another major work summarized in this thesis achieved temperature mapping with a Rhodamin B (RhB) grafted microfluidic chip. RhB fluorescence intensity is temperature dependent, thus it is commonly used in biotechnology for temperature sensing and as a tracer. By grafting RhB on PDMS, this functional material provides a non-invasive, rapid, full-field, high spatial resolution and acquisition rate temperature sensing method, while the material possesses excellent solvent, thermal and photo stability. 2D temperature mapping of a microfluidic chip is demonstrated, spatial resolution was estimated to be 5 μm.

While many methods exist to separate and analyze radionuclides from a variety of environmental matrices, the performance of all of these methods is often limited by other interfering constituents that are consistently found in most of these samples. The presence of such constituents can significantly reduce the recovery of the radioisotopes of interests and lead to incomplete separations. Strontium has the same oxidation state and a similar atomic radius as calcium and is therefore readily able to substitute for calcium in lattice sites. This similarity in behavior leads to the preferential accumulation of strontium in newly formed bone. The study of radiostrontium uptake and the analysis of bone samples is therefore of great interest for radiation biology, internal dosimetry, and consequence management. The fact that one of the strontium isotopes of greatest biological importance,90Sr, is a pure beta-emitter prevents the use of non-destructive assay techniques and necessitates the development of sophisticated separation methods for radiochemical analysis. It has been previously reported in the literature that the matrix constituents present in bone can significantly affect the strontium recovery from bone samples1. Bone (hydroxyapatite) is of particular interest when evaluating the effect of common environmental interferences due to the high concentrations of calcium and phosphate present. The goal of this work is to determine the major and minor constituents present in various samples of bone ash and to determine their influence on method performance and strontium recovery. The work presented exploited the use of a variety of radioanalytical separation and isotope detection techniques. Focusing on the characterization of the bone ash, Scanning Electron Microscopy and X-ray Powder Diffraction techniques were used to determine the morphology, to verify the crystalline pattern, and to analyze for any contaminants within each unique bone ash sample. The information ob

Soil contamination by crude oil is a major environmental and health hazard. The main goal of this research was to investigate the applicability of using a solid-liquid two-phase partitioning bioreactor (TPPB) to remediate crude oil contaminated kaolin. To achieve this objective, sorption studies were carried out on kaolin contaminated by crude oil using commercial thermoplastic polyurethane (Desmopan®) and 2-propanol as a mobilizing agent followed by bio-regeneration of crude oil loaded polymer beads in the TPPB. The equilibrium sorption capacity (qe) as well as the kinetic behaviour of the thermoplastic polyurethane (TPU) was determined as a function of the crude oil dilution with 2-propanol. The polymeric sorbent exhibited the highest qe value when immersed in a 50% diluted crude oil. The sorption experimental data correlated well with different kinetic models. The Elovich kinetic model correlated accurately with the diluted crude oil experimental data; while the pseudo-first order and pseudo-second order kinetic models could also predict the sorption of n-alkanes (C14-C36) and polycyclic aromatic hydrocarbons (PAHs) into the polymeric sorbent, respectively. Parameters of the power law model showed that the mechanism of transport for both diluted and undiluted-crude oil into the TPU was Fickian. The sorption kinetics of the PAHs and the short-chain n-alkanes (C14-C18) were also shown to be a direct function of their octanol/water partitioning coefficient. In contrast, the sorption rates of the long chain n-alkanes (C20-C36) were inversely associated with their molecular volumes. Finally, intraparticle diffusion analysis indicated that the 2-propanol present in crude oil had reduced both the external and the internal mass transfer resistances within the internal structure of the TPU. A central composite design (CCD) under response surface methodology (RSM) was employed for experimental design in kaolin remediation study and analysis of the results. The influences o

Yin, Weixin = 非晶液態鈀-鎳-磷合金相位分離的證據 / 殷瑋欣., Thesis (M.Phil.)--Chinese University of Hong Kong, 2011., Includes bibliographical references., s in English and Chinese., Yin, Weixin = Fei jing ye tai ba-nie-lin he jin xiang wei fen li de zheng ju / Yin Weixin., Acknowledgement --- p.i, p.ii, Contents --- p.iv, Chapter Chapter 1 --- Introduction --- p.1, Chapter 1.1 --- A Brief Introduction to Metallic Glass --- p.1, Chapter 1.2 --- Homogeneous Nucleation Frequency --- p.3, Chapter 1.3 --- Heterogeneous Nucleation Frequency --- p.4, Chapter 1.4 --- Spinodal Decomposition --- p.5, Chapter 1.5 --- Conditions for Metallic Glasses Formation --- p.8, Chapter 1.6 --- How to Get Large Undercooling --- p.9, Chapter 1.7 --- Liquid Phase Separation --- p.10, References --- p.12, Figures --- p.13, Chapter Chapter 2 --- Experimental Procedures and Techniques of Transmission Electron Microscopy --- p.18, Chapter 2.1 --- Sample preparation --- p.18, Chapter 2.1.1 --- Ni2P Preparation --- p.18, Chapter 2.1.2 --- Alloying --- p.18, Chapter 2.1.3 --- Fluxing --- p.18, Chapter 2.2 --- Introduction to TEM Specimen Preparation --- p.19, Chapter 2.2.1 --- "Grinding, Polishing and Punching" --- p.19, Chapter 2.2.2 --- Final Thinning by Ion Miller --- p.20, Chapter 2.2.3 --- Final Thinning by Twin Jet --- p.20, Chapter 2.3 --- Introduction to Transmission Electron Microscopy Techniques --- p.21, Chapter 2.3.1 --- Basic Instrumentations of TEM --- p.21, Chapter 2.3.2 --- Elastic Scattering and Inelastic Scattering --- p.21, Chapter 2.3.3 --- Image Contrast --- p.22, Chapter 2.3.4 --- Dark Field Image and Bright Field Image --- p.24, Chapter 2.3.5 --- EDX Mapping --- p.24, Chapter 2.3.6 --- High Resolution Images --- p.25, References --- p.26, Figures --- p.27, Chapter Chapter 3 --- Evidence of amorphous/liquid phase separation in Pd41.25Ni41.25P17.5 alloy --- p.32, Chapter 3.1 --- Introduction --- p.32, Chapter 3.2 --- Experimental --- p.34, Chapter 3.3 --- Discussions --- p.42, References --- p.44, Figures --- p.45, Chapter Chapter 4 --- Conclusions --- p.68, http://library.cuhk.edu.hk/record=b5894648, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

A Master of Science Thesis in Chemical Engineering submitted by Noor Ali Abachi entitled, "Control and Optimization of Membrane Biological Reactor Processes," January 2011. Available are both soft and hard copies of the thesis., Membrane biological reactor (MBR) is an emerging technology adopted for domestic and industrial wastewater treatment. The high selectivity of the semi permeable membrane to water results in membrane fouling. Fouling is a highly nonlinear phenomenon that affects the MBR stability, productivity, and performance. Many techniques are proposed to minimize and control fouling such as backwashing and aeration. However, such techniques may lead to high operation costs and high energy consumption rates. Therefore, optimization of MBR operating conditions is essential in order to achieve effective, stable, and economical MBR operation. In this study, a rigorous mathematical model is developed for the MBR. The model is derived by performing a mass balance on three major parameters, the substrate concentration, the biomass concentration, and the Oxygen concentration. Then, kinetic models representing the major reactions in the MBR are stated. Four kinetic parameters namely, the maximum specific biomass growth rate, net biomass yield, Monod constant, and endogenous decay coefficient are estimated using experimental data. Further, an empirical flux model is proposed representing the flux exponential decline behavior. The flux model also requires the estimation of two constants representing the cake growth. Hence both the kinetic and flux parameters are estimated using POLYMATH nonlinear regression. Combining the mass balance equations along with the corresponding kinetic models and the estimated kinetic parameters yields to a system of first order nonlinear coupled ODEs. Hence solving such system online is inefficient due to the large computational time and effort. Thus artificial neural networks (ANNs) are suggested for MBR modeling. The input and output variables are first selected for the ANN model. The selected input variables are the backwash pressure, vacuum pressure, and ratio of vacuum-to-backwash time, while the flux is selected as the output variable. Different ANN mode, College of Engineering, Department of Chemical Engineering

Batch settling is a widely used method to separate a flocculated suspension into concentrated sediment and a clear liquid. Experimental and theoretical studies of this process have been published for almost a century due to its importance in separation processes. Fundamental aspects of sedimentation and suspension flows include properties of suspensions (concentration and viscosity); individual particles (particle size and shape, particle-particle interaction, surface charge); and sediments (permeability, porosity and compressibility). The investigated material, MCC, is of great interesting for several different applications, e.g. in the food and pharmaceutical industry. Hence, this work investigates the sedimentation process of micro crystalline cellulose in order to understand its behaviour considering the different conditions set out. Based on the results obtained in this work the following conclusions can be drawn: both the sedimentation behaviour and the compressibility of the sediment are affected by the surface charge of the MCC particles; finally, the solidosity of the sediment is as a function of pH.

La gestion ou la décontamination des REFIOM (Résidus d’Epuration des Fumées d’Incinération d’Ordures Ménagères) est impérative avant de la mise en décharge de ces déchets. Ils sont considérés comme déchets dangereux car ils libèrent des quantités importantes de chlorures et métaux lourds quand sont en contact avec de l’eau. En fait, les REFIOM agroupent différents types de résidus provenant des traitements des fumées. Ce travail est partie d’une recherche qui est centrée sur les Cendres Volantes d’Electro-filtre (CVE) et son traitement. Ce traitement des CVE est basé sur une séparation granulométrique des fractions valorisables de ces qui sont contaminées, afin d’obtenir des résidus valorisables ou acceptables en décharge. Cette séparation est effectuée en utilisant une solution dense qui contient, parmi des autres composés, des quantités importantes en sels de chlorure ainsi qu’une présence de métaux lourds à considérer. La fraction des CVE valorisable suivit différentes étapes de lavage à l’eau et aux réactifs pour la décontaminer. Dans ce travail on a effectué des recherches pour traiter cette solution dense afin de la recycler dans ce procédé de lavage et en conséquence, économiser de l’eau. Ils sont deux groupes de contaminants sur lesquels l’étude s’est centrée : les sels de chlorure de sodium et potassium ; et les métaux lourds, concentrèrent le plomb et le zinc. Un traitement d’évaporation-refroidissement est proposé afin de décontaminer la solution des sels par précipitation. En plus, avec le protocole suivi on a prétendu obtenir les précipités de NaCl séparés de ces de KCl. Les résultats obtenus montrent que par évaporation il est possible d’obtenir des précipités presque sélectifs de NaCl. Par contre, en laissant refroidir cette solution (qui est traitée par évaporation), on obtient un mélange en sels de NaCl et KCl. L’eau évaporée pendant l’évaporation pourrait être condensé et envoyée dans une ligne de lavage des CVE. La solution finale présente encore, Outgoing

The separation between actinides and fission products could be realized by a pyrometallurgical liquid/liquid extraction process. Thanks to an oxide-reductive reaction, a mass exchange occurs at the interface between a polluted molten salt layer and a containment loquid metal layer. The aims of this project is to develop the diffusion process which occurs and the thermodynamics process associated to this phenomena. This work consist in two parts: -An experimental prototype industrial type installed in the laboratory. -A bibliography on diffusivity coefficients of pollutants in molten salts.

Most energy scenarios suggest carbon capture and storage (CCS) from power generation might contribute to achieve the carbon emissions reduction necessary to stabilize the long-term global average atmospheric temperature. Low temperature CO2 capture represents a novel alternative to the state-of-the-art monoethanolamine (MEA) post-combustion technology. The separation process aims to reduce the flue gas temperature from the ambient temperature to a low temperature range necessary to freeze the CO2.The potential reduction in overall energy consumption and the simplicity of the separation system compared to MEA suggest that the low temperature CO2 capture concept might be a cost-effective technology necessary to be further analyzed. However, designing a low temperature carbon capture system involves complex challenges including solid formation and handling, heat transfer at low temperatures and process integration. In this investigation a supersonic Laval nozzle has been modeled in one dimension to analyze the nozzle flow behavior with particle formation. Specifically this study seeks to understand and predict the desublimation of carbon dioxide present in the flow. The primary objective is the basic design of a converging diverging nozzle capable to desublimate carbon dioxide from low concentration flue gases by at least 50% for a range of inlet flow conditions and properties. The inlet conditions are limited to 5% CO2 by mol of flue gas present in the flow. The second objective is the optimization of the nozzle pressure recovery system. A preliminary analysis of the various processes that take place in the nozzle has been performed and the governing equations have been implemented into a coupled 1D set of differential equations. Based on the 1D model a design tool has been developed that allows for the prediction of the main flow parameters throughout the nozzle. The predictions have been verified by comparison with experiments available in the open literature. A des, Outgoing

Das vorgestellte Dokument präsentiert die Diplomarbeit mit dem Titel Untersuchung der Trenncharakteristiken eines Hydrozyklons bei einer zusätzlichen Wasserinjektion. Diese Diplomarbeit ist im Rahmen des Projekts der Erasmus-Mobilität zwischen der Escola Tècnica Superior d’Enginyeria Industrial de Barcelona und der Technischen Universität Erlangen-Nürnberg durchgeführt worden, insbesondere am Lehrstuhl für Umweltverfahrenstechnik und Recycling (LUR) der Technischen Universität Erlangen- Nürnberg. Diese Arbeit ist in sieben Kapitel gegliedert. Das erste Kapitel beschreibt das Ziel und den Anwendungsbereich des Projekts. Im zweiten Kapitel wird kurz das Problem der Trennung von feinen Partikeln und die Grundlage der Injektion mit dem Beispiel der Fallstudie erklärt, in der es um eine Mischung von feinen Partikeln (Kaolin 70% mit 30% Feldspat) geht. Außerdem wird auch der Begriff der Trennkurve eingeführt, obwohl ihre mathematische Beschreibung in dem Punkt 4.3 vorgestellt wird. Das dritte Kapitel besteht aus zwei grossen Abschnitten: ein historischer Überblick und eine Beschreibung der Maschine was sowohl ihre Handhabung als auch ihre Geometrie angeht. Das vierte Kapitel zeigt die Hypothese der Studie, das mathematisch verwendete Modell (Modell der Querrströmungsklassifikators) und die Gleichung. Außerdem wird der Fish-Hook-Effekt präsentiert. Im fünften Kapitel werden die Werkstoffe, die Methodik und die Arbeitsweise des Mastersizers X-2000 vorgestellt. Dies geschieht mit dem Ziel, alle experimentellen Arbeiten im Detail zu beschreiben. Ausserdem werden auch die Vorteile der Verwendung des Mastersizers gegenüber anderen älteren Methoden der Messung der Partikelgrößen der Proben genauer geschildert. Das sechste Kapitel enthält drei Hauptabschnitte: die Trennkurven in Abhängigkeit von der Injektion, vergleichende Grafiken der Trenncharakteristiken abhängig von dem Verhältnis der Wassereinspritzung und dem Druck und schließlich die allgemeine Beschreibung dieser Variabl, Outgoing

Outgoing

En el siguiente estudio se propone el diseño completo de una unidad desbencenizadora. La función primordial de dicha unidad será separar el benceno a partir de una alimentación compuesta por naftas de reformado. Posteriormente, la unidad devolverá tres corrientes, dos de ellas con contenido muy bajo en benceno y la otra con elevada concentración de este. Las corrientes de baja concentración se utilizarán para hacer gasolinas y la de alta concentración se enviará a plantas dedicadas a la elaboración de plásticos. La cantidad de benceno en cada una de las corrientes de salida vendrá implantada por una serie de directivas de carácter legislativo llamadas “Auto-oil”, de cumplimiento obligatorio para todos los países miembros de la Unión Europea. La separación principal de la alimentación se llevará a cabo mediante una torre de destilación completa trabajando en continuo. Para ejecutar las diferentes funciones auxiliares de la unidad, como el bombeo, el enfriamiento y el control de las corrientes de proceso, se utilizarán bombas, intercambiadores de calor, depósitos y válvulas. El estudio se ha estructurado en diferentes apartados, y en cada uno de ellos se han desarrollado diferentes temáticas específicas relacionadas con el diseño integral de la unidad desbencenizadora. Inicialmente, se ha buscado el punto de funcionamiento óptimo de la unidad, todo ello con la ayuda de simuladores y hojas de cálculo. Una vez determinadas las condiciones de operación se ha procedido a dimensionar y caracterizar todos los equipos necesarios para el perfecto funcionamiento de la unidad. En los apartados finales se han tratado aspectos como el control, la seguridad y el análisis económico, con los que se ha intentado completar lo máximo posible el desarrollo del diseño. Finalmente, y a modo de demostración, se ha propuesto una unidad alternativa con idénticas condiciones en la entrada y en las salidas pero con distintos equipos asociados a las diferentes partes del proceso. Esto se ha hec

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La région de Tadoussac est située dans la partie est-centrale de la province de Grenville entre les rivières Saguenay et Saint-Laurent. Les principaux types de roches sont, 1) Orthogneiss gris granodioritiques, 2) Métasédiments incluant des métapelites métamorphisé au faciès amphibolitique supérieur, 3) Gneiss mafiques et 4) Les granites alcalins. Le pluton granitique a été injecté dans une faille de décrochement active pendant la mise en place du magma. À l'échelle de l'affleurement, du coté sud-ouest, ce pluton est en contacte intrusif avec les gneiss mafiques à intermédiaires, et recoupe la foliation générale ainsi que les dykes de granites et des pegmatites associés. Ces roches mafiques à intermédiaires se trouvent dans la faille en décrochement dextre, elles enregistrent une foliation importante et hébergent des veines de ségrégation du matériel leucocrate parallèle à la foliation ainsi que des structures extensionnelles, qui ressemble amplement a des leucosomes d'une migmatite, en plus, il y a des zones ou les amphiboles sont transformées en biotite évoquant un patron de fractures. Sur une base pétrographique, on note que les ségrégations dans les roches mafiques présentent des microstructures magmatiques. L'absence de paragenèse minéralogique qui peut suggérer des réactions anatectiques favorise l'interprétation selon laquelle, les roches mafiques dérivent du magma mafique injecté et cristallisé dans la faille active. Les évidences géochimiques montrent que les unités mafiques sont tholéiitiques et alcalines, ces caractères proviendraient d'une source magmatique enrichie en alcalins, ce qui met à l'évidence un processus de contamination crûstale du magma. La composition des ségrégations dans les roches mafiques peut être expliqué plutôt par une ségrégation de liquide résiduel que par une fusion partielle faute d'existence de liquide anatectique. Donc, l'interprétation est celle de deux magma alcalins, l'un felsique l'autre mafique qui s'injectent en même temp

Miniaturized analytical systems have been widely investigated over the past decade due to their tremendous advantages over conventional systems and their potential applications to many areas. In general, a chemical or biochemical analysis requires multiple steps, of which separation is an essential one. Electrical field flow fractionation (EFFF) is a flow-based separation technique that combines an electric field and a perpendicular hydrodynamic flow with a parabolic profile. It gains several advantages by miniaturization due to a stronger electric field and a reduced channel thickness. Moreover, its simple device structure and its wide applicability make EFFF possible to be integrated with other micro modules. However, the major problem of EFFF is the weak effective field for separation across its flow channel due to the double layers on the electrode surfaces. In this thesis, we firstly overcome the problem of the weak effective field by applying a pulsed voltage on the EFFF, and advance this technique and the corresponding micro device for the separation of nanoparticles and biomolecules. The dynamics of the electrical double layer in a micro EFFF (μ-EFFF) device is analyzed numerically and characterized experimentally. The device consists of two indium tin oxide (ITO) electrodes with a flow channel, and it is fabricated using micromachining technology. In comparison to the constant voltage operation, the μ-EFFF device operated with pulsed voltage obtains a stronger electric field. The practical use of pulsed voltage in the micro device is explored by investigating the retention and separation of polystyrene nanoparticles. A longer retention time was measured for higher pulse frequencies. The improved separation of nanoparticles with different surface charges and sizes was demonstrated. Pulsed voltage operation does not only overcome the weak effective field, but also offers additional parameters, such as the pulse frequency and waveform to optimize its separatio

by Yuen Cheong Wing., Thesis (M.Phil.)--Chinese University of Hong Kong, 1996., Includes bibliographical references (leaves [138]-[142])., by Yuen Cheong Wing., Acknowledgments --- p.ii, p.iii, Table of Contents --- p.v, Chapter Chapter 1: --- Introduction --- p.1-1, Chapter 1.1 --- What is Metallic Glass? --- p.1-1, Chapter 1.2 --- Use of Metallic Glass --- p.1-3, Chapter 1.3 --- A Dilemma --- p.1-4, Chapter 1.4 --- Glass Forming Ability --- p.1-5, Chapter 1.5 --- Role of Liquid State Phase Separation in GFA --- p.1-6, References --- p.1-9, Figure --- p.1-10, Chapter Chapter 2: --- Phase Separation Theory --- p.2-1, Chapter 2.1 --- Free Energy Curve --- p.2-1, Chapter 2.2 --- Nucleation and Growth --- p.2-2, Chapter 2.2.1 --- Liquid state nucleation and growth --- p.2-2, Chapter 2.2.2 --- Nucleation and growth during solidification --- p.2-4, Chapter 2.3 --- Spinodal Decomposition --- p.2-5, Chapter 2.3.1 --- Cahn-Hilliard linearized equation --- p.2-6, Chapter 2.3.2 --- Temporal evolution --- p.2-9, References --- p.2-12, Figures --- p.2-15, Chapter Chapter 3 ： --- Experimental Setup and Techniques --- p.3-1, Chapter 3.1 --- Technique in Achieving High Undercooling --- p.3 -1, Chapter 3.1.1 --- Effects and limitation of B203 --- p.3-1, Chapter 3.1.2 --- Preparation of B203 --- p.3-3, Chapter 3.1.3 --- Cleansing of apparatus --- p.3-4, Chapter 3.2 --- Experimental --- p.3-5, Chapter 3.2.1 --- Sample preparation --- p.3-6, Chapter 3.2.2 --- Experimental setup --- p.3-7, Chapter 3.2.3 --- Procedures --- p.3-8, Chapter 3.3 --- Observing the Microstructure --- p.3-9, Chapter 3.3.1 --- Cutting --- p.3-10, Chapter 3.3.2 --- Molding --- p.3-10, Chapter 3.3.3 --- Polishing --- p.3-11, Chapter 3.3.4 --- Etching --- p.3-12, Chapter 3.3.5 --- Observation --- p.3-12, References --- p.3-14, Table --- p.3-15, Figures --- p.3-16, Chapter Chapter 4: --- Metastable liquid phase separationin undercooled molten PD40. 5]\l40.5P19 --- p.4-1, p.4-1, References --- p.4-9, Figures --- p.4-10, Chapter Chapter 5 ： --- Transformation in undercooled molten PD40.5NI40.5P19 --- p.5-1, Chapter 5.1 --- Abstract --- p.5-1, Chapter 5.1 --- Introduction --- p.5-2, Chapter 5.3 --- Experimental --- p.5-4, Chapter 5.4 --- Results --- p.5-6, Chapter 5.5 --- Discussions --- p.5-13, References --- p.5-20, Figures --- p.5-22, Chapter Chapter 6 ： --- Solidification of liquid spinodal in undercooled PD40.5NI40.5P19 --- p.6-1, Chapter 6.1 --- Abstract --- p.6-1, Chapter 6.2 --- Introduction --- p.6-2, Chapter 6.3 --- Experimental --- p.6-3, Chapter 6.4 --- Results --- p.6-5, Chapter 6.5 --- Discussions --- p.6-10, References --- p.6-17, Figures --- p.6-18, Chapter Chapter 7: --- Conclusion --- p.7-1, References --- p.7-4, Bibliography --- p.B-1, http://library.cuhk.edu.hk/record=b5888966, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Lee Ka-lun., Thesis (Ph.D.)--Chinese University of Hong Kong, 1996., Includes bibliographical references., Acknowledgments --- p.ii, p.iii, Table of Contents --- p.v, Chapter Chapter 1: --- Introduction --- p.1, Chapter 1.1 --- Phase Separation in Glass-Forming Alloys --- p.2, Chapter 1.1.1 --- Metallic Glass --- p.2, Chapter 1.1.2 --- Phase Separation in Metallic Glasses --- p.3, Chapter 1.1.3 --- Phase Separation in the Undercooled Melts of Glass-Forming Alloys --- p.4, Chapter 1.2 --- Theory of Phase Separation --- p.5, Chapter 1.2.1 --- Thermodynamics of Phase Separation --- p.5, Chapter 1.2.2 --- Phase Separation by Nucleation and Growth --- p.7, Chapter 1.2.3 --- Cahn's Theory of Spinodal Decomposition --- p.8, Chapter 1.3 --- Experimental Method to Achieve High Undercooling --- p.11, References --- p.14, Figures --- p.15, Chapter Chapter 2: --- Phase Separation in Undercooled Molten Pd80Si20 --- p.23, p.24, Introduction --- p.25, Experimental --- p.29, Results --- p.30, Discussions --- p.36, References --- p.45, Figures --- p.47, Chapter Chapter 3: --- Metastable Liquid Phase Separation in Undercooled Molten Pd40.5Ni40.5P19 --- p.60, p.61, Introduction --- p.62, Experimental --- p.62, Results and Discussions --- p.63, References --- p.68, Figures --- p.69, Chapter Chapter 4: --- Crystallization of Spinodal Decomposed Melts of Pd80Si20 --- p.74, Introduction --- p.75, Experimental --- p.76, Results --- p.77, Discussions --- p.80, References --- p.84, Figures --- p.85, http://library.cuhk.edu.hk/record=b5888833, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Three rain events were sampled from a storm drain at Manassas Mall in Manassas, Virginia. The urban runoff samples obtained were placed into lab-scale Plexiglas~ settling columns to monitor removal of total hydrocarbons (THC) by extended quiescent settling. Samples were collected from the columns at specific depths and times over the 48-hour settling period. The samples were analyzed for total hydrocarbon content on a Horiba oil content analyzer. Hydrocarbon values were averaged at each column depth in order to construct average THC concentration and average THC percent removal profiles over settling time. Maximum average THC removals were 77.8%,32.5%, and 73.6%, respectively, for Storms #1, 2, and 3 after 48 hours of quiescent settling. These average removals corresponded to depths of -2 feet, -1 foot, and -3 feet in the 5-foot tall columns. According to traditional sedimentation theory, pollutants settle out of water to the bottom of the container of interest. This did not appear to be solely the case in this hydrocarbon sedimentation study. It appeared that sedimentation was not the sole removal mechanism at work. Some fractions of oil and grease seemed to reorganize into low-density sub-groups and float to upper regions of the column. Also, the majority of THe removal occurred within the first 18 hours of settling for two of the three storms sampled.

Methods for the analysis of surfactants and proteins by Capillary Electrophoresis (CE) were investigated. Several modifications of the system to achieve detection and separation of these analytes were examined. These modifications included buffer additives, sample additives and surface treatment and modification of the fused silica capillary. For the analysis of anionic surfactants, the addition of an anionic IN absorbing compound to the buffer was investigated to achieve indirect detection of the non-absorbing surfactants. The effect on detection sensitivity and separation efficiency of the absorbing ion was examined. These parameters were affected by differences in the electrophoretic mobilities of the analytes in comparison to the absorbing ion. The use of organic modifiers was also investigated to minimize micelle formation of the surfactants which leads to zone spreading. For the analysis of serum and urine proteins, the use of high pH buffers was investigated to minimize solute/capillary surface interactions and achieve separation. At high pH's the proteins are negatively charged; therefore, they should be repelled by the negatively charged fused silica surface. To improve reproducibility of migration times of the proteins the addition of polyvinyl alcohol to the sample was also investigated. The polyvinyl alcohol improved reproducibility by reversibly covering the active sites on the capillary surface to minimize protein interactions. Migration time reproducibility was also improved by optimizing the capillary cleaning procedure. Lastly, the addition of methyl cellulose to the buffer to work as a dynamic molecular sieving medium was investigated to improve resolution. Analyte/ capillary surface interactions are a major limitation in CE especially for the analyses of proteins. The use of coated capillaries to eliminate these interactions has been widely investigated. However, reproducibility and degree of surface deactivation with these coating can be poor. In

Expert systems are being used more daily in chemical engineering. This work continues the development of an EXpert system for SEParation flowsheet synthesis named EXSEP. Written in Prolog, it can generate flowsheets for four multicomponent separations: distillation, absorption, stripping and liquid-liquid extraction. For these separations, we describe a large collection of heuristics (or rules) that are used for flowsheet synthesis. EXSEP uses several of these heuristics and the Kremser equation to test the thermodynamic feasibility of separation tasks. EXSEP requires only basic input data such as the expected component flow rates in each product and the component K-values. With those data, EXSEP searches for the sets of the number of theoretical stages, solvent flow rate, and component-recovery ratios that characterize a number of feasible and economical flowsheets. The use of the component assignment matrix (CAM) combined with Prolog list processing makes EXSEP very fast (several seconds) to generate solutions. We test EXSEP with several examples of industrial separation processes and compare the results with the literature. We also compare EXSEP results with rigorous simulations using commercial CAD software (e.g., DESIGN II). In most cases, EXSEP gives very similar and even better flowsheets. However, EXSEP is limited to dilute solvent-based separations and cannot solve problems where the major feed component is also the solvent (e.g. sour-water steam stripper). The development of EXSEP on IBM-PC makes it very "user friendly". In the future, EXSEP should be expanded with additional modules such as extractive and azeotropic distillation, and bulk absorption. It should also include modules for separation method and solvent selections, which are great challenges in flowsheet synthesis.

The present study addresses a systematic evaluation of the effect of crosslinking via terminal maleimide units on the gas transport properties through a dense polymer film of amorphous Poly(Arylene Ether Ketones) or PEK. The methodology for the preparation of crosslinked maleimide terminated PEK (or MIPEK) films from several blend ratios of different molecular weights of MIPEK is discussed in detail. The primary focus of this work has been to investigate the influence of different degrees of crosslinking on gas permeabilities and selectivities, with an objective of producing a highly selective membrane. It has been demonstrated that crosslinking markedly decreases the permeation of methane, without changing the values for molecules such as helium.