Probiotics and prebiotic are becoming increasingly important to consumers to alleviate issues surrounding gut health, despite the lack of definitive efficacy studies to support health claims. The addition of both probiotics and prebiotics to foods is challenging due to the harsh environmental conditions within the food itself and during transit through the gastrointestinal (GI) tract. To circumvent these challenges encapsulation technology is being explored to protect sensitive ingredients and to control their release within the lower intestines thereby maximizing the health benefiting effects. The overall goal of this research was to design a protein delivery capsule using phase separated pea protein isolate (PPI)-alginate (AL) mixtures for the entrapment of the synbiot which includes the probiotics, Bifidobacterium adolescentis, and the prebiotic, fructooligosaccharides (FOS), such that the capsule design provides highly effective protection and release within the GI tract. Research was carried out in three studies.<p> In study 1, PPIn (native isolate) and AL interactions were studied in dilute aqueous solutions as a function of pH and biopolymer mixing ratio. Turbidimetric analysis and electrophoretic mobility during an acid titration was used to determine conditions where phase separation occurred. Critical structure forming events associated with the formation of soluble and insoluble complexes in a 1:1 PPIn-AL mixture were found to occur at pH 5.00 and 2.98, respectively, with optimal interactions occurring at pH 2.10. As the PPIn-AL ratio increased, critical pH values shifted towards higher pH until a mixing ratio between 4:1 and 8:1was reached, above which structure formation became independent of the ratios through to ratios of 20:1. Electrophoretic mobility measurements showed a similar trend, where the isoelectric point (pI) shifted from pH 4.00 (homogeneous PPIn) to pH 1.55 (1:1 PPIn-AL). As the ratio increased towards 8:1 PPIn-AL, net neutrality values shifted to higher pHs (~3.80) before becoming constant at higher ratios. Maximum coacervate formation occurred at a mixing ratio of 4:1. Based on these findings, capsule design by segregative phase separation was only used in future studies, due to the acidic nature associated with associative phase separation.<p> In study 2, capsule formation using a native and commercial PPI was studied, and showed no difference between the two formulations during challenge experiments in simulated gastric juice (SGJ). As a result study 3 focused on optimization and characterization of capsules prepared using the commercial PPI. Capsule designs were investigated as a function of protein concentration, prebiotic level, and extrusion conditions (20 vs. 27 G needle) in order to determine protective ability for B. adolescentis within SGJ. Capsule designs were also measured in terms of protein and prebiotic retention during the encapsulation process, geometric mean diameter and size distribution, swelling behaviour and release characteristics within simulated intestinal fluids (SIF). All capsules provided adequate protection over the 2 h duration within SGJ. Capsule breakdown and release was similar for all designs within SIF, with a release mechanism believed to be tied to enzymatic degradation of the PPI material within the wall matrix and/or the amount of excessive Na+ present in the SIF. Capsule size was found to be dependent only on the needle gauge used in the extrusion process. Swelling behaviour of the capsules with SGJ was also found to be dependent only on the protein concentration, where capsules shrank once immersed in SGJ.<p> A 2.0% PPI-0.5% AL capsule without FOS and extruded through a 20 G needle represents the best and most cost effective design for entrapping, protecting and delivering probiotic bacteria. Future work to establish the role FOS could play post-release as the entrapping probiotics colonize the GI tract, and the protective effect of the capsules wall on FOS structure during transit is recommended.

During embryonic development, precursor germ cells contain aggregates of protein and RNA known as germ granules. These germ granules are important in the specifi- cation of a functioning germ line, i.e. functioning sex cells within mature organisms. In the single cell fertilized embryo of the nematode worm C.elegans, germ granules (referred to as P granules) localize to the posterior side of the cell. After cell division occurs, they are found only in the posterior daughter cell. The localization behav- ior of P granules has been a topic of much interest, and considered an important aspect of symmetry breaking during development. We learn the fundamental prop- erties of P granule localization, and determine possible parameters and features of this biological system by developing theory in close collaboration with experimental evidence. In this study, experimental evidence is presented which shows that P granules are liquid droplets, and that their localization occurs through preferential nucleation and growth behavior on one side of the cell and simultaneous preferential dissolution on the opposite side. It is also shown that this behavior is linked to the concentration gradient of the protein Mex-5 along the anterio-posterior axis of the cell, which is necessary to induce the preferential growth of P granules. From this experimental data, a theoretical model for the preferential growth of P granules is developed, where the localization of P granules occurs by phase separa- tion. That is, P granules separate from the bulk cytoplasm by a process described by a first order liquid-liquid phase transitition, where a liquid droplet granule phase nucleates and then grows out of the bulk liquid cytoplasmic phase. In this model, a spatial gradient is imposed on the saturation point, the boundary point between the single phase state consisting only of the cytoplasm, and a metastable state which includes both a P granule and cytoplasm phase. This gradient mimics the properties of the Mex-5 gradient and is sufficient in explaining P granule localization. Using numerical simulations, the theoretical model is studied. It is found suffi- cient to both successfully describe P granule localizaion, and to describe interesting behavior in a system with assymetric growth due to a spatial gradient. From a purely theoretical standpoint, we observe cyclical non-equilibrium steady states, where material is cycled back and forth along the gradient. From the biological side, experimental properties of the system, such as the diffusion coefficient of P granules and P granule growth rates are determined through both simulation and image analysis of data. In addition, the possiblility of different types of growth behavior at later cell stages, and a method of long range intracellular signalling are suggested from the theoretical model.

Probiotics and prebiotic are becoming increasingly important to consumers to alleviate issues surrounding gut health, despite the lack of definitive efficacy studies to support health claims. The addition of both probiotics and prebiotics to foods is challenging due to the harsh environmental conditions within the food itself and during transit through the gastrointestinal (GI) tract. To circumvent these challenges encapsulation technology is being explored to protect sensitive ingredients and to control their release within the lower intestines thereby maximizing the health benefiting effects. The overall goal of this research was to design a protein delivery capsule using phase separated pea protein isolate (PPI)-alginate (AL) mixtures for the entrapment of the synbiot which includes the probiotics, Bifidobacterium adolescentis, and the prebiotic, fructooligosaccharides (FOS), such that the capsule design provides highly effective protection and release within the GI tract. Research was carried out in three studies.<p> In study 1, PPIn (native isolate) and AL interactions were studied in dilute aqueous solutions as a function of pH and biopolymer mixing ratio. Turbidimetric analysis and electrophoretic mobility during an acid titration was used to determine conditions where phase separation occurred. Critical structure forming events associated with the formation of soluble and insoluble complexes in a 1:1 PPIn-AL mixture were found to occur at pH 5.00 and 2.98, respectively, with optimal interactions occurring at pH 2.10. As the PPIn-AL ratio increased, critical pH values shifted towards higher pH until a mixing ratio between 4:1 and 8:1was reached, above which structure formation became independent of the ratios through to ratios of 20:1. Electrophoretic mobility measurements showed a similar trend, where the isoelectric point (pI) shifted from pH 4.00 (homogeneous PPIn) to pH 1.55 (1:1 PPIn-AL). As the ratio increased towards 8:1 PPIn-AL, net neutrality values shifted to higher pHs (~3.80) before becoming constant at higher ratios. Maximum coacervate formation occurred at a mixing ratio of 4:1. Based on these findings, capsule design by segregative phase separation was only used in future studies, due to the acidic nature associated with associative phase separation.<p> In study 2, capsule formation using a native and commercial PPI was studied, and showed no difference between the two formulations during challenge experiments in simulated gastric juice (SGJ). As a result study 3 focused on optimization and characterization of capsules prepared using the commercial PPI. Capsule designs were investigated as a function of protein concentration, prebiotic level, and extrusion conditions (20 vs. 27 G needle) in order to determine protective ability for B. adolescentis within SGJ. Capsule designs were also measured in terms of protein and prebiotic retention during the encapsulation process, geometric mean diameter and size distribution, swelling behaviour and release characteristics within simulated intestinal fluids (SIF). All capsules provided adequate protection over the 2 h duration within SGJ. Capsule breakdown and release was similar for all designs within SIF, with a release mechanism believed to be tied to enzymatic degradation of the PPI material within the wall matrix and/or the amount of excessive Na+ present in the SIF. Capsule size was found to be dependent only on the needle gauge used in the extrusion process. Swelling behaviour of the capsules with SGJ was also found to be dependent only on the protein concentration, where capsules shrank once immersed in SGJ.<p> A 2.0% PPI-0.5% AL capsule without FOS and extruded through a 20 G needle represents the best and most cost effective design for entrapping, protecting and delivering probiotic bacteria. Future work to establish the role FOS could play post-release as the entrapping probiotics colonize the GI tract, and the protective effect of the capsules wall on FOS structure during transit is recommended.

In den letzten Jahren belegt eine stark ansteigende Anzahl experimenteller und theoretischer Resultate das große Interesse an Volumenmaterialien mit elektronischer, struktureller und/oder chemischer Heterogenität auf der Skala von 0,5 bis 2 nm. Solche Clustermaterialien lassen hervorragende Eigenschaften erwarten, wenn vorteilhafte strukturelle oder elektronische Konfigurationen kombiniert werden können. Ein interessanter neuer Ansatz zur Erzeugung von Heterogenitäten in metallischen Gläsern sind zusätzliche Legierungselemente mit positiven Mischungsenthalpien zwischen mindestens zwei der Komponenten. Die abstoßende Wechselwirkung zwischen zwei Hauptkomponenten kann zu einer Mischungslücke in der Schmelze und sogar zur Bildung phasenseparierter metallischer Gläser führen. Diese Gläser bestehen aus Volumenanteilen mit amorpher Struktur, aber unterschiedlicher Zusammensetzung. Es wurde bereits gezeigt, dass in massiven metallischen Gläsern in einigen Fällen eine verbesserte Plastizität und sogar eine erhöhte Glasbildungsfähigkeit erreicht werden kann, falls ein geringer Massenanteil eines Legierungselements mit positiver Mischungsenthalpie zugegeben wird. In der vorliegenden Arbeit wird die Herstellung von Clustermaterialien von Legierungen mit metallischer Glasbildungsfähigkeit und deren Eigenschaften untersucht. In Levitationsexperimenten wurde zunächst die Phasenseparation in unterkühlten Schmelzen der binären Systeme mit positiver Mischungsenthalpie Gd-Ti und Gd-Zr in einer elektromagnetischen Levitationsanlage experimentell aufgeklärt. Wenn Schmelzen unter die Binodale unterkühlt werden, entmischen sie in Bereiche mit unterschiedlicher Zusammensetzung. Aus den signifikanten Unterschieden der Gefüge von Proben, die von einem Zustand innerhalb bzw. außerhalb der Mischungslücke auf einem Kupfersubstrat abgeschreckt wurden, konnte die Form der Mischungslücke in der Gd-Ti Schmelze als Funktion der Temperatur und der Konzentration bestimmt werden. Diese erstreckt sich von 10 bis 80 At.% Gadolinium und ist wesentlich ausgedehnter als bisher vermutet. Ihre kritische Temperatur 1580 ◦C liegt bei der Zusammensetzung Gd20 Ti80. Im Gegensatz zu Gd-Ti konnte für Gd-Zr Schmelzen wegen der geringeren positiven Mischungsenthalpie keine stabile Mischungslücke gefunden werden. Jedoch deutet die simultane dendritische Kristallisation der Primärphasen Gadolinium und Zirkonium in bis zu 100 K unterkühlten Proben auf die Existenz einer metastabilen Mischungslücke unterhalb der eutektischen Temperatur hin. Eine durch CAL- PHAD Rechnungen vorhergesagte Mischungslücke in der Schmelze des quaternären Systems Gd-Ti-Cu-Al, für das dünne Bänder phasenseparierter Gläser mit dem Schmelzspinnverfahren hergestellt wurden, konnte nicht bestätigt werden. Die mit der elektromagnetischen Levitationsanlage erreichte minimale Abschrecktemperatur (920◦C) läßt aber keine endgültige Aussage zu. Ein weiteres Ziel der Arbeit ist es, die Wirkung geringer Anteile der Elemente Gadolinium, Kobalt und Rhenium auf eine Cu-Zr-Al Legierung mit guter Glasbildungsfähigkeit zu ermitteln. Die genannten Elemente zeichnen sich durch positive Mischungsenthalpie sowie Mischungslücken in Schmelzen mit unterschiedlichen Hauptkomponenten der binären Randsysteme Gd-Zr, Cu-Co bzw. Cu-Re der Basislegierung aus. Die Wirkung dieser Mikrolegierungselemente auf Glasbildungsfähigkeit, Struktur, thermische Stabilität und mechanische Eigenschaften erwiesen sich als abhängig vom Mikrolegierungselement, seiner Konzentration und den Abkühlbedingungen. Massive metallische Gläser mit Durchmessern 2 bis 6 mm der Zusammensetzung (Cu46Zr46Al8)100−xZx (x=0−4) konnten für Z=Gd, Co mit dem Spritzgießverfahren hergestellt werden. Dabei erhöht sich die Glasbildungsfähigkeit für geringe Gd-Beimischungen sogar bis 2 At.%, während sie für Kobalt nur leicht reduziert wird. In Abhängigkeit von x verringern sowohl Gadolinium als auch Kobalt die Kristallisationstemperatur der Cu46Zr46Al8 Basislegierung um bis zu 25 K, während die Glasbildungstemperatur Tg nahezu unverändert bleibt. Legieren mit optimalen Gehalten von Gadolinium und Kobalt bis zu 2 At.% führt zu einer plastischen Verformbarkeit im Vergleich zum spröden Verhalten des massiven metallischen Glases Cu46Zr46Al8. Im Druckversuch wurden z.B. Bruchdehnungen bis εf = 4% in (Cu46Zr46Al8)98Co2- bzw. (Cu46Zr46Al8)98Gd2-Proben mit 3mm Durchmesser erreicht. Die maximale Druckfestigkeit und der Elastizitätsmodul bleiben gegenüber der Basislegierung nahezu unverändert. Weite Gebiete der Bruchflächen solcher mikrolegierter Gläser zeigen die Abwesenheit von Scherbändern, was ein Zeichen für eine inhomogene Verformung ist und zum Versagen der Proben führt. Selbst geringe Zugaben von Rhenium (1 At.%) setzen die Glasbildungsfähigkeit drastisch herab. Es konnten nur amorphe Folien von ca. 40 μm Dicke durch Splat- Quenching hergestellt werden, obwohl sich die Kristallisationstemperatur für (Cu46Zr46Al8)98Re2 etwas erhöht. Gegossene massive Proben besitzen ein kristallines Gefüge bestehend aus Primärdendriten der intermetallischen Verbindung B2-CuZr und der kubischen Phase CuZrAl als Hauptbestandteile. Kleine Teilchen einer Rereichen Phase sind unregelmäßig in der Probe verteilt. Diese werden beim Erstarrungsprozess zuerst ausgeschieden und triggern offensichtlich die Kristallisation der B2-CuZr Phase, wie Gefügebilder beweisen. Die massiven Gussproben besitzen außergewöhnliche mechanische Eigenschaften, hohe Festigkeit verbunden mit plastischer Dehnung bis 4 % und einen ausgedehnten Bereich der Kaltverfestigung bei reduzierter Streckgrenze gegenüber den metallischen Gläsern. Diese Eigenschaften werden durch den hohen Volumenanteil der B2-CuZr Phase bestimmt. Das Mikrolegieren mit Elementen positiver Mischungsenthalpie sowie die gezielte Keimbildung stabiler bzw. metastabiler kristalliner Phasen durch Ausscheidungen in der Schmelze, die in dieser Arbeit verfolgt wurden, sind aussichtsreiche Konzepte zur Optimierung mechanischer Eigenschaften von Materialien auf der Basis von massiven metallischen Gla ̈sern. Die Bildung nanokristalliner Clusterstrukturen und der Mechanismus der Verbesserung der plastischen Verformbarkeit bedürfen zukünftig vertiefter wissenschaftlicher Untersuchungen.

The study proposed a high efficient dye sensitize solar cell (DSSC) by embedding liquid crystal in liquid electrolyte. When liquid crystal molecules was disperse in the liquid electrolyte, the light-scattering occur due to refractive index mismatching by randomly oriented liquid crystal droplets. The light-scattering allows solar light have longer optical path length within the solar cell and therefore enhances light-trapping efficiency of N719 dye. The experiment results reveal that the DSSC with the liquid crystal concentration of 20 wt% have best electric conversion efficiency. Moreover, the study also introduces chloseteric liquid crystal to the liquid electrolyte of a DSSC and compare with nematic liquid crystal embedded DSSC. The cholesteric liquid crystal with periodic helical structure in the liquid electrolyte provides not only light-scattering but also selective reflection. Compared with nematic liquid crystal embedded DSSC, the cholesteric liquid crystal embeded DSSC has a more large light-trapping efficiency due to combined effects of light scattering and selective reflection. Besides, when the reflective band (480~580nm) of cholesteric liquid crystal is matched to the absorption spectrum of N719 dye, the DSSC has better photoexcitation of dye and photovoltaic performance.

Proton Exchange Membrane Fuel Cell has the potential to become an important energy conversion technigne. Lots of efforts oriented toward the electrochemical conversion of energy using proton exchange membrane (PEM) fuel cells have been enormously accelerated with the hope to promote as an alternative power source for transport and portable purposes. However, they still suffer from such disadvantages as limited operation temperature, high cost, insufficient durability and high methanol permeability.Good membranes should meet several strict requirements as follows; reasonable proton conductivity, high stability and durny the performance of a fuel cell environment,outstanding mechanical toughness, high heat endurance, and impermeability to fuel gas or liquid. Presently,a lot of references have mentioned some sulfonatied polymer sulfonated of poly(ether ether ketone) (SPEEK), sulfonatedpolysulfone (SPSF), sulfonated polysulfide sulfone(SPSS), and polybenzimidazole(PBI) and so on.To achieve high proton conductivity usually match with a high degree of sulfonation that means owning a large Ion Exchange Capacity, IEC.But which in turn leads to a decrease in the electrochemical¡Bdimensional stability¡Bwater uptake¡Boxidative stability. Therefore they suffer from such disadvantages as limited operation range of temperature.Three aromatic poly(arylene ether)s P4b¡BP4c¡BP4d were synthesized from the polymer consists nine of polyaromatic groups with bisfluoride monomer at studying long time in our laboratory with S1¡BS2¡BS3 diol monomer.The molecular weight of the polymer (Mw:1.49¡Ñ105~5.3¡Ñ105 g/mol ,PDI: 1.82~2)This polymer has high strength,thermal stability and all of polymers own very high Td ,which are over than 500oC.We sulfonatied the polymer in order to apply as the proton exchange membrane of a fuel cell.The results showed after sulfonation of P4b¡BP4c¡BP4d.All IEC reaches 3.9~1(meq/g).According to above result, we propose the aromatic poly(arylene ether)s is good matenal can be used on all application as a proton exchange membrane.

Four denture base materials of poly(methyl methacrylate) (QC-20, Pladent-20, Hygenic, and Optilon-399) were prepared by convention water bath and microwave-energy cured methods. While the resin was in the dough stage, it was packed into two molds (65 mm ¡¦15 mm ¡¦10 mm) in the fiber reinforced plastic flask. The variation of temperature with time was recorded by two thermocouples during the microwave heating at 80, 160, and 240 watts, respectively. Microwave polymerization was carried out in the same equipment. The microwave flask containing the same size of resin blocks were processed at 80, 160, 240, and 560 watts for 15, 10, 7, and 2 min, separately. Then each flask was turned over, and cured an additional 2 min at 560 watts. In the case of water-bath method, the resin in the dough stage was packed in the Brass flask, and then cured at 70¢J for 9 hours. Ten specimens were prepared for each condition studied. The surface hardness, porosity, flexural properties and solubility of both process conditions were evaluated. The samples were sectioned by microtome and stained 2 % Osmiun tetroxide, then the morphology of Optilon-399 was observed by using TEM (Transmission electron microscopy) at 160 KV. The result indicate that the flexural strength for Optilon-399 specimens prepared by water-bath method was 20 MPa higher than that prepared in microwave oven, however, there were no obvious difference between the samples cured at different power. Phase separation in two different sizes was observed in all of the Optilon-399 specimens. The larger domain was with 0.18 mm~0.67 mm diameter has dispersed rubber phase surrounded by a rubber periphery. The smaller domain with 0.1 mm diameter is rich with rubber phase. The size and distribution of the larger domain were correlated with the microwave power and curing time. The sample cured by water-bath has the largest average domain diameter (0.395¡Ó0.068 mm). In the specimens prepared by microwave method, the domain size decreased with increasing power. In additions, the domain size varied across the specimen. The size difference between the largest and the smallest domain for specimens cured at 80W was 0.03 mm, and that for specimens cured at 560W was 0.05 mm. This indicated that the larger the power watt was, the higher the morphology difference was.

Solid-state complexes between diblock copolymer and amphiphilic surfactant (surf) results in polymers characterized by two length scales with one macroscopic ¡§block copolymer length¡¨ and one mesomorphic ordered ¡§nanoscale¡¨. In this study, the desired polymer was prepared by complexing the surf molecules, i.e., 4-dodecylbenzenesulfonic acid (DBSA), with polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP) and a comb-coil A-block-(B-graft-C) type copolymer can be generated through a supramolecular assembly route. On the block copolymer scale, the PS blocks are phase-separation from the P4VP(DBSA)x block, which x denotes the molar ratio between DBSA and pyridine groups. Bonding interaction between PS-b-P4VP and DBSA was conformed by FTIR. PLM was used to detect the mesomorphic structure within P4VP(DBSA)x block. In all cases, we found that birefringent can be only found in copolymer with their comb content exceeding 63 wt%. In the thermal analysis, shows us that the glasses transition temperature(Tgs) of the P4VP(DBSA)x block increases with the increasing DBSA content, a result related to the stiffening of the P4VP main chain due to dense packing. On the mesomorphic nanoscale, wide-angle X-ray diffraction study suggests an ordered supramolecular layer structure was formed in most of the complexation cases, in which the thicknesses of the polymer and surf layers were determined from the one-dimensional correlation function. The result indicates that both layers thickness increase with increasing DBSA amounts due to the stretching of the long alkyl tail in DBSA. Finally, macroscopic morphology varied with the DBSA content according to TEM results.

This diploma thesis presents experimental evidence of a theoretical concept which predicts the self-organization of delta-layers of silicon nanoclusters in the buried oxide of a MOS-like structure. This approach of "bottom-up" structuring might be of eminent importance in view of future semiconductor memory devices. Unconventionally, a 15nm thin SiO2 layer, which is enclosed by a 50nm poly-Si capping layer and the Si substrate, is irradiated with Si+ ions. Ion impact drives the system to a state far from thermodynamic equilibrium, i.e. the local composition of the target is modified to a degree unattainable in common processes. A region of SiOx (x<2) - where x is a function of depth - is formed which is not stable. During annealing, the system relaxes towards equilibrium, i.e. phase separation (via spinodal decomposition and nucleation) sets in. Within a certain time window of annealing, the structure of the system matches with a structure similar to the multidot non-volatile memory device, the principal character of which is a 2D layer of Si nanoclusters of ~3nm in diameter which is embedded in a 3D SiO2 matrix at a distance of ~3nm from the Si substrate. The physical mechanisms of ion mixing of the two Si-SiOx interfaces and subsequent phase separation, which result in the desired sample structure, are elucidated from the viewpoint of computer simulation. In addition, experimental evidence is presented based on various methods, including TEM, RBS, and SIMS. Of particular importance is a novel method of Si nanocluster decoration which applies Ge as contrast enhancing element in TEM studies of tiny Si nanoclusters.

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