Cyclic sieving phenomenon (CSP) is a generalization by Reiner, Stanton, White of Stembridge's q=-1 phenomenon. When CSP is exhibited, orbits of a cyclic action on combinatorial objects show a nice structure and their sizes can be encoded by one polynomial. In this thesis we study various proofs of a very interesting cyclic sieving phenomenon, that jeu-de-taquin promotion on rectangular Young tableaux exhibits CSP. The first proof was obtained by Rhoades, who used Kazhdan-Lusztig representation. Purbhoo's proof uses Wronski map to equate tableaux with points in the fibre of the map. Finally, we consider Petersen, Pylyavskyy, Rhoades's proof on 2 and 3 row tableaux by bijecting the promotion of tableaux to rotation of webs. This thesis also propose a combinatorial approach to prove the CSP for square tableaux. A variation of jeu-de-taquin move yields a way to count square tableaux which has minimal orbit under promotion. These tableaux are then in bijection to permutations. We consider how this can be generalized.

tert-butyl 1-methoxycarbonyl-1-ferrocenecarbamate, Boc-NH-Fc-COOMe, (1) was synthesized according to the literature procedure and modified to 1-amino-n′-ferrocenemethylcarboxylate, 1,n′-H2N-Fc-COOCH3 (2) by removing the Boc-group with TFA/Et3N mixture in dichloromethane. Compound 2 reacted with alkylating agents like MeI, EtI, EtSCH2CH2Cl (MA) and (CN)(EtO)2P(O) (NA) to form MeNH-Fc-COOMe (3), EtNH-Fc-COOMe (4), EtSCH2CH2NH-Fc-COOMe (5), (EtO)2P(O)NH-Fc-COOMe (6), respectively. Cyclic voltammetry (CV) of these compounds showed different half-wave potential characteristics compared to aminoferrocene and was dependent on the nature of the substituents, which was rationalized by molecular orbital calculations. Electron donating groups (Me, Et and 2-chloroethyl ethylsulfide, MA) shifted the half-wave potential towards the cathodic direction while electron withdrawing group like diethyl cyanophosphonate, NA, shifted it toward anodic direction. Anodic to cathodic peak separation were found to be within 62-88 mV indicating a quasi-reversible system. <p>Hydrolysis of compound 1 resulted in the formation of tert-butyl 1-methoxycarbonyl-1-ferrocenecarboxylic acid, Boc-NH-Fc-COOH, (11) which was coupled with cystamine using the EDC/HOBt protocol to synthesize the cystamine conjugate [BocHN-Fc-CO-CSA]2 (12). This molecule is equipped with an amino group that directly linked to the redox receptor. Compound 12 was fully characterized by spectroscopic methods and by single crystal x-ray diffraction. The cystamine conjugate 12 formed films on gold substrates, which upon deprotection of the amino group, reacted with chemical warfare agents (CWAs) mimics, such as EtSCH2CH2Cl (MA), a simulant for the sulfur mustard HD, and (CN)(EtO)2P(O) (NA), a simulant for the nerve agent Tabun. Their reaction with the surface-bound ferrocene derivative results in the formation of N-substituted products. <p>CV measurements showed anodic shifts of the Fc redox potentials by 50 (±5) mV after exposure to MA, and NA. Measurements by quartz crystal microbalance (QCM) showed an increase in mass upon exposure to MA and NA. Ellipsometry measured a film thickness increase from 6 (±1) Å for the deprotected film to 10 (±4) Å for the film modified with MA and to 7 (±2) Å for the film modified with NA. The surfaces were analyzed by x-ray photoelectron spectroscopy (XPS) and clearly showed the attachment of the cystamine conjugate on the surface and its reaction with CWAs mimics.

Abstract The study on SOC of article is one of package way for CSP. The SOC transmits messages by Solder Ball joining the board. It can make the volume of product decrease, but the reliability reduces on using. So the reliability of Solder Ball is a very important topic for study. The article for Solder Ball uses the Mixed-Viscoplastic way to simulate the warpage state of SOC when the temperature of Solder Ball rises by ANSYS. Then using the Viscoplastic material parameter simulates the acts by TCT experiment and checks the suitable Fatigue Model to get the analysis results turn into the reliability data. The reliability data puts to the proof with the experimental reliability data and compares differences to other documents.

The objectives of this study were to 1) determine the effects of cycle-to-cycle variations (ccv) on nitric oxide (NO) emissions, and 2) determine if the consideration of ccv affects the average NO emission as compared to the mean cycle NO emission. To carry out the proposed study, an engine simulation model was used. The simulation determines engine performance and NO emissions as functions of engine operating conditions, engine design parameters, and combustion parameters. An automotive, spark-ignition engine at part load and 1400 rpm was examined in this study. The engine cycle simulation employed three zones for the combustion process: (1) unburned gas, (2) adiabatic core region, and (3) boundary-layer gas. The use of the adiabatic core region has been shown to be especially necessary to capture the production of nitric oxides which are highly temperature dependent. Past research has shown that cyclic variations in combustion cause ccv of burn duration, ignition delay and equivalence ratio. Furthermore, literature has shown that variations of these three input parameters may be approximated by a normal frequency distribution. Using the mean and standard deviation, and a random number generator, input values were tabulated for the ignition delay, burn duration and equivalence ratio. These three input parameters were then used to simulate cyclic variations in the combustion process. Calculated results show that cyclic variations of the input parameters cause the cycle-by-cycle NO emissions to increase and decrease by as much as 59% from the mean cycle NO of 3,247 ppm. The average NO emission resulting from ccv was 4.9% less than the mean cycle NO emission. This result indicates that cyclic variations must be considered when calculating the overall NO emissions.

A novel method to enhance oil production during cyclic steam injection has been developed. In the Top-Injection and Bottom-Production (TINBOP) method, the well contains two strings separated by two packers (a dual and a single packer): the short string (SS) is completed in the top quarter of the reservoir, while the long string (LS) is completed in the bottom quarter of the reservoir. The method requires an initial warm-up stage where steam is injected into both strings for 21 days; then the LS is opened to production while the SS continues to inject steam for 14 days. After the initial warm-up, the following schedule is repeated: the LS is closed and steam is injected in the SS for 21 days; then steam injection is stopped and the LS is opened to production for 180 days. There is no soak period. Simulations to compare the performance of the TINBOP method against that of a conventional cyclic steam injector (perforated across the whole reservoir) have been made. Three reservoir types were simulated using 2-D radial, black oil models: Hamaca (9°API), San Ardo (12°API) and the SPE fourth comparative solution project (14°API). For the first two types, a 20x1x20 10-acre model was used that incorporated typical rock and fluid properties for these fields. Simulation results indicate oil recovery after 10 years was 5.7-27% OIIP with TINBOP, that is 57-93% higher than conventional cyclic steam injection (3.3-14% OIIP). Steam-oil ratios were also decreased with TINBOP (0.8-3.1%) compared to conventional (1.2-5.3%), resulting from the improved reservoir heating efficiency.

Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / "December 2001." Typescript. Vita. Includes bibliographical references (leaves 95-113). Also available on the Internet.

Thesis (M.S.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009. / Committee Chair: Weck, Marcus; Committee Member: Collard, David; Committee Member: Kubanek, Julia. Part of the SMARTech Electronic Thesis and Dissertation Collection.

The first instability of circular tubes compressed into the plastic range is axisymmetric wrinkling, which is stable. Compressed further the wrinkle amplitude grows, leading to a limit load instability followed by collapse. The two instabilities can be separated by strain levels of a few percent. This work investigates whether a tube that develops small amplitude wrinkles can be subsequently collapsed by persistent cycling. The problem was first investigated experimentally using SAF 2507 super-duplex steel tubes with D/t of 28.5. The tubes are first compressed to strain levels high enough for mild wrinkles to form and then cycled axially under stress control about a compressive mean stress. This type of cycling usually results in accumulation of compressive strain; here it is accompanied by growth of the amplitude of the initial wrinkles. The tube average strain initially grows nearly linearly with the number of cycles, but as a critical value of wrinkle amplitude is approached, wrinkling localizes, the rate of ratcheting grows exponentially and the tube collapses. Similar experiments were then performed for tubes involving axial cycling under internal pressure and the combined loads cause simultaneous ratcheting in the hoop and axial directions as well as a gradual growth of the wrinkles. The rate of ratcheting and the number of cycles to collapse depend on the initial compressive pre-strain, the internal pressure, and the stress cycle parameters all of which were varied sufficiently to generate vii a sufficient data base. Interestingly, in both the pressurized and unpressurized cases collapse was found to occur when the accumulated average strain reaches the value at which the tube localizes under monotonic compression. A custom shell model of the tube with initial axisymmetric imperfections, coupled to the Dafalias-Popov two-surface nonlinear kinematic hardening model, are presented and used to simulate the experiments performed. It is demonstrated that when suitably calibrated this modeling framework reproduces the prevalent ratcheting deformations and the evolution of wrinkling including the conditions at collapse accurately for all experiments. The calibrated model is then used to evaluate the ratcheting behavior of pipes under thermal-pressure cyclic loading histories experienced by axially restrained pipelines. / text

published_or_final_version / Anatomy / Master / Master of Philosophy

Previous in vitro studies showed that exchange protein directly activated by cyclic AMP 1 (Epac1), which is a cAMP mediator, plays an important role in maintenance of endothelial barrier function. Diabetic retinopathy is characterized by impairment of retinal blood vessel integrity leading to breakdown of blood retinal barrier, retinal hypoxia, and neuronal damage. Here, we hypothesize that Epac1 regulates endothelial permeability and protects retina from the retinal damage associated with diabetes. To test such hypothesis, we first demonstrated that human retinal microvascular endothelial cells (HRMECs) exposed to high glucose concentration at 25 mM or 35 mM showed the decreased Epac1 expression level. Our preliminary data also showed that Epac1-downstream activator, Rap1, a member of Ras GTPase, was also altered by different glucose levels. In addition, retina from type 2 diabetic, db/db, mice also showed the decreased Epac1 expression compared to that of non-diabetic, db/m, mice. To further determine the role of Epac1 in diabetic retinopathy, we made use of Epac1-deficient mice. The pathogenesis of diabetic retinopathy share similar characteristics to that of ischemic retinopathy, such as neuronal cell death, glial reactivity, and glutamate toxicity. Therefore, we used our previous retinal ischemic model, i.e., transient middle cerebral artery occlusion (tMCAO). Firstly, we determined the retinal morphology of Epac1-/- mice under normal condition at 3wks. At 3 wks old, the Epac1-/- retinae showed a significantly decreased thickness of outer plexiform layer (OPL) with a trend of increase in inner nuclear layer (INL) thickness. Interestingly, there were obviously more glutamine synthetase (GS)-positive M?ller cells and protein kinase C (PKC)-α positive rod bipolar cells in INL. In addition, there were more IgG-positive blood vessels in OPL. To further determine whether these phenotypes will lead to more severe retinal damage, Epac1-/- mice were exposed to 2 hours of MCAO followed by 22 hours of reperfusion, which we have previously shown to induce retinal ischemia. There was no obvious difference in retinal thickness and expressions of glial fibrillary acidic protein (GFAP) and GS in the contralateral sides of Epac1+/+ and Epac1-/- retina after tMCAO suggesting that the Epac1-deficiency may be compensated by either protein kinase A (PKA) or Epac2. However, Epac2 level was not altered by Epac1-deficiency by Western blot analysis. The ipsilateral sides of the retina of Epac1+/+ and Epac1-/- after tMCAO also did not show obvious difference in swelling and cell death in inner retina, GFAP, glutamate, GS, nitrotyrosine (NT), and peroxiredoxin 6 (Prx6), suggesting that Epac1-deficiency may have been compensated by other cAMP mediators, such as Epac2. However, Epac2 expression in the ipsilateral side of Epac1+/+ and Epac1-/- retinae was not significantly different, although the activities of Epac and PKA were not determined. Taken together, the Epac1-deficient mice would serve as a useful model to determine the role of Epac1 in retinal development, and to determine the detail mechanisms of pathogenesis of diabetic and ischemic retinopathy. / published_or_final_version / Anatomy / Master / Master of Philosophy