This study describes the use of human serum albumin (HSA)-modified gold nanoparticles (HSA-AuNPs) for the selective extraction and enrichment of high-pI protein, lysozyme (Lyz) prior to analysis by capillary electrophoresis (CE) with UV detection. HSA-AuNPs are capable of extracting Lyz from a complicated matrix because a HSA capping layer not only stabilizes gold nanoparticles in a high-salt environment but also exhibits strong electrostatic attraction with Lyz under neutral pH condition. Efficient separation of Lyz and other high-pI proteins has been successfully achieved by the filling of cationic polyelectrolyte, poly(diallydimethylammonium chloride) (PDDAC), to the background electrolyte. After capturing Lyz with HSA-AuNPs, PDDAC-filled CE can be directly used for the analysis of the extracted Lyz without the addition of the releasing agent into the extractor. The extraction efficiency relied on the pH of the solution and the concentration of HSA-AuNPs. Under optimal extraction conditions, the limits of detection at a signal-to-noise ratio of 3 for Lyz were down to 8 nM. The combination of HSA-AuNP extraction and PDDAC-filled CE has been applied the analyses of lysozyme in chicken egg white, white wine and human tear. Also, we reveal that this NP-based extraction can be coupled to matrix-assisted desorption/ionization time-of-flight mass spectrometry.

This work presents a modeling and control study of a reactive distillation column used for hydrogenation of benzene. A steady state and a dynamic model have been developed to investigate control structures for the column. The most important aspects of this control problem are that the purity of the product streams regarding benzene need to be met. At the same time as little toluene as possible should be converted. The former is a constraint imposed by EPA regulations while the latter is tied to process economics due to the high octane number of toluene. It is required to satisfy both of these objectives even under the influence of disturbances, as the feed composition changes on a regular basis. The dynamic model is used for developing transfer function models of two potential control structures. Pairing of inputs and outputs is performed based upon the Relative Gain Array (RGA) and PI controllers were designed for each control structure. The controller performance was then compared in simulation studies. From our results, control structure 2 performed better than control structure 1. The main advantage of CS2 over CS1 is noticed in the simulation of feed composition disturbance rejection, where CS2 returns all variables back to steady state within 3 hrs while it take CS1 more than 20 hrs to return the temperature variables back to steady state.

Mass spectrometry (MS) has played a major role in the proteomic analysis of an array of biological samples. Even so, inherent limitations exist such as sample complexity and the dynamic range. In an attempt to overcome these limitations, prefractionation is typically performed followed by reversed phase liquid chromatography coupled with MS. Pre-fractionation can be performed in several formats including chromatographic or electrophoretic based methods. Solution-based isoelectric point (pI) fractionation, specifically isoelectric trapping (IET), provides an attractive alternative for pre-fractionation in bottom-up proteomic studies. A recently developed device, membrane separated wells for isoelectric focusing and trapping (MSWIFT), provides rapid separation on the basis of pI and resulting solutions are MS compatible without the need for extensive sample cleanup. Initial experiments demonstrate fractionation using MSWIFT, of peptide mixtures ranging from standards to a yeast lysate where resulting fractions are analyzed using matrixassisted laser desorption/ionization (MALDI) – MS or further separated using reversed phase liquid chromatography followed by tandem MS (MS/MS) analysis. Identified yeast proteins range in size, pI and copy number illustrating an ability to increase the depth of proteome coverage when using MSWIFT. Extensive studies were also performed using MSWIFT in a multi-stage fractionation platform to improve peptide and protein identifications for the first large-scale proteomic study of the model fungus, Neurospora crassa. A second focus of this work is the development of a new sample preparation method for proteolytic digestion and high-throughput separations using MSWIFT. Histidine is used as a neutral pH, isoelectric, sample buffer for tryptic digestion of proteins and also assists in rapid separations using MSWIFT owing to the low conductivity. Tryptic digests of individual standard proteins and a mixture of standard proteins are used to illustrate these advantages. Finally, the histidine buffer sample preparation method is incorporated into a two-dimensional separation strategy. Tryptic peptides are fractionated using MSWIFT and resulting solutions are further separated using capillary electrophoresis (CE) coupled with MALDI-MS/MS. Performing the two-dimensional strategy allows for increased confidence in peptide and protein assignment owing to experimentally determined in-solution charge states and estimated pI values.

Sol-gel process was utilized to produce organic/inorganic composite in this research, and the effect of mixing time¡]of polymer¡¦s and silica¡¦s precursor¡^ and coupling agent were investigated. To get low к materials was also the important objective. TMA, TGA, SEM, FT-IR, and RF impedance were used to investigate thermal properties, chemical bonding, morphology, and dielectric constant, respectively. The experiments showed that mixing time influence little to thermal stability but a lot to morphology and к. When mixing time was nearer to reaction time, the particle of silica was larger and the surface was flatter. The materials with coupling agent didn¡¦t show the same tendency as one without coupling agent. Regardless of coupling agent, it got larger к when mixing time was nearer to reaction time. Comparing with pure polymer, the modified materials got lower к. The lowest к got in this research was 2.36 which was lower than other materials.

The thesis aims to the research of active power factor correction (PFC) circuit and develop a DSP-based digital controller. In the thesis, PI controller is the control core for the voltage loop¡Band current loop, and then achieve the function of the power factor correction of boost converter. Finally, we develop a boost converter and connect it to a DSP-based controller to measure the waveforms and verify the power factor correction. Furthermore, the research can be extended to a simulating platform which we can verify the power factor correction by just changing the control law on DSP .

Following the model developed by Easley, Kiefer, O¡¦Hara and Paperman (1996), I estimated the probability of informed trading (PI) in the TSEC. The result in my study is that the probability of informed trading is highly related with the trading volume of each stock. More active stocks will have lower probability of informed trading, so investors trading with active stocks will face less information asymmetry. Feather more, my research followed the study of Easley, Hvidkjaer, and O¡¦Hara (2002), who used the Fama-French asset pricing model(1992) discussing the relationship among stock return, portfolioed market risk, size and BE/ME ratio. The result in my study is that the stock return in TSEC is affected by portfolioed market risk and size, but PI and BE/ME ratio have no effect to stock return. The result is different from the study of Easley, Hvidkjaer, and O¡¦Hara (2002). The reason could be that most investors in TSEC are individuals who lack the awareness about information asymmetry.

<p>ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.</p><p>Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.</p><p>At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters. The</p><p>standard deviation in the moisture was decreased from a level of 0.32%, measured when the process was manually controlled, down to 0.07% measured when the control system was used. This also solved the given problem.</p>

Die heterobimetallischen Pi-Pinzetten können erfolgreich als Grundbaustein für die Darstellung von mehrkernigen Übergangsmetallkomplexen, in denen die Metallzentren M(I) (M = Cu, Ag) über unterschiedliche stickstoffhaltige organische sigma-Donor-Liganden verbrückt sind, verwendet werden. In Abhängigkeit von der Natur der korrespondierenden organometallischen Pi-Pinzetten und der organischen Brückeneinheiten konnten verschiedene mehrkernige Übergangsmetallkomplexe synthetisiert werden. Diese Komplexe wurden mittels IR, 1H- und 13C-NMR-Spektroskopie sowie MS charakterisiert. Die Festkörperstrukturen ausgewählter Komplexe konnten durch Einkristall-Röntgenstrukturanalyse erhalten werden. Die Wechselwirkungen der Kupfer(I)- sowie Silber(I)-Ionen, über die koordinativ gebundenen stickstoffhaltigen. Stichworte: Organometallischen À-Pinzetten; Bis(alkinyl)titanocene; Titanium; À- Konjugierte; Mehrkernigen; Kupfer(I), Silber(I).

Non-covalent interactions are of great interest to chemists and biologists who study the molecular structure and function of biological systems, as well as those who seek to control, undo, or improve upon the efficiency of these systems with man-made chemical tools. The Iverson group has specifically applied noncovalent aromatic donor-acceptor interactions to biotic and abiotic aqueous systems through the use of the electron-rich 1,5-dialkoxynaphthalene (DAN) and electron-deficient 1,4,5,8-naphthalenetetracarboxylic diimide (NDI) moieties. Chapter 1 introduces and reviews the current state of self-assembly research, especially work conducted in aqueous media. Chapter 2 delineates the design and synthesis of a molecule that can self-assemble and form disulfide bonds, with the goal of creating higher-order structure. Chapter 3 comprises the design and synthesis of a series of pendant-NDI bisintercalators of DNA that are distinct from the backbone-incorporated intercalators previously employed in our laboratory. Chapter 4 contextualizes the term of art “pi-stacking,” reviewing the current state of knowledge of specific contributions to this effect and commenting on the putative uniqueness of the interaction. Theoretical and experimental work in the field is summarized. The work discussed in this dissertation serves to expand the scope of programmability of our DNA intercalators, to probe the higher-order assembly behavior of our donor-acceptor pair, and to clarify the term “pi-stacking,” lately overused, that imperfectly describes the interaction that gives both these systems their compelling binding properties. / text

Because bimolecular interactions in water are poorly understood, three tactics commonly used to improve binding affinity in ligand design were investigated: (1) increasing apolar surface area, (2) introducing a conformational constraint, and (3) targeting a cation-[pi] interaction. Thermodynamic parameters of binding ligands to the Grb2 SH2 domain were determined by isothermal titration calorimetry (ITC), and structural data was obtained by X-ray crystallography. The apolar surface area of the pTyr+1 residue in Ac-pTyr-Acnc-Asn-NH₂ was varied by incrementally increasing the size of the cyclic Acnc residue from a 3-membered to a 7-membered ring. Increasing apolar surface area resulted in an increase in Ka due to a more favorable [delta]H⁰ that was dominated a less favorable [delta]S⁰. Structural analyses showed that all ligands bound in a similar mode, so differences in binding thermodynamics were attributed to the pTyr+1 residue. The thermodynamics of binding tripeptides wherein pTyr+1 was an n-alkyl group were studied. Ka increased when Ala was mutated to Abu, but additional methylene groups had no effect on Ka due to strong entropy-enthalpy compensation. While [delta]H⁰ was weakly correlated with buried surface area, there was no change in [delta]H⁰ between one methylene and two methylene groups, presumably because an enthalpic penalty is associated with a gauche interaction between C-[beta] and C-[gamma] of the Xaa side chain that was noted in the crystal structure. An olefin was installed in an attempt to alleviate the energetic penalty incurred from the gauche interaction, but the introduction of the constraint resulted in equipotent ligands. A putative cation-[pi] interaction between Arg67 and various aromatic groups was probed by varying the [pi]-donating capability of groups attached to a tripeptide scaffold. Although crystal structures demonstrated that three of the aryl groups were close enough to Arg67 to form a cation-[pi] interaction, only a modest increase in Ka was observed relative to analogues having only an N-acetyl group. Furthermore, a simple cyclohexyl group in place of aryl groups resulted in ligands that were equipotent with indolyl- and phenyl- derived analogues, so any cation-[pi] interaction is not significant. / text