79 research outputs found
Study of Silicon Solar cell Array to Power MEMS Cantilever Actuator
A solar cell array to power a on board microelectromechanical polysilicon cantilever actuator was designed, fabricated and tested. The device composes of two solar cell arrays one array with 330 solar cells and another array with 300 solar cells. The device also consists of several cantilevers. The fabrication process involved over fifty process steps including nine photolithography levels. To optimize the performance of the solar cell array the entire process was simulated using SILVACO SUPREM simulation software. Electrical examination using ATLAS software allowed for parameter extraction of the computer-generated solar cells. Modeling the extracted parameters with device physics equations allowed for a SPICE level-2 analysis that could be verified through electrical testing of the actual fabricated solar cells. Measurements were made throughout the fabrication process. The completed devices were tested and pictures were taken of the cantilevers and solar cell array
Modification, characterization, analysis and life-science application of polymers: Polypropylene
Three stepwise chemical approaches were developed to transform commercially available isotactic polypropylene tubes into specialty' plastics for application in the life sciences: Oxidation. Ordinary polypropylene surfaces were oxidatively transformed inlo highsurface plastics bearing reactive surface groups by reaction with aqueous persulfate. Attcnuated-Total-Refiectance (ATR) infrared spcctroscopic analysis indicated that ketone, carboxylic acid and hydroxyl groups were afforded within the plastic. Surface analyses using optical microscopy revealed the formation of macroscopic parallel cracks. More importantly, scanning electron microscopy indicated the reacted material had developed a mesoscopic topology remarkably similar in appearance to microvilli. Protein immobilization experiments conducted using (luorescently labeled albumin served to quantify the performance of oxidized surfaces. Facile detection by visual observation under OV light disclosed that adsorbed protein was released during sequential washings of the tubes in high salt, low salt and detergent solutions. TEOS deposition. Hydrolysis products of tetraethoxysilane were cured onto oxidized, high-surface polypropylenes, affording tubes coated with prc-glass layers on the walls. ATR infrared spcctroscopic analyses verified the glass-like end product. These modified surfaces possessed the appropriate physico-chemical trails to reversibly bind mRNA, thus establishing the concept of a tube-mediated approach to purify mRKA out of total RNA. Protein could also be reversibly bound to the surface Triaminopropylsilane deposition. Oxidized surfaces were transformed using Ihe hydrolysis products of trimethoxysilylpropyldiethylenetriaminc to afford functional surfaces bearing surface-pendent amino groups. ATR infrared spectroscopy revealed that the network formed by triaminopropylsilyl moieties described a thin coating upon the surface. Ninhydrin coiorimctric analyses indicated that the surface amino group loading per unit frontal area had increased by an order of magnitude in comparison to commercially animated surfaces. As in the case of the TEOS tubes, the amino-modified tubes adsorbed protein reversibly. The amino moieties were subsequently transformed with glutaraldehyde solutions to afford surface-bound aldehyde functional groups. This time, immobilization studies using fluorescent albumin indicated that protein retention was remarkably resistant to washings with high salt, low salt and detergent solutions. In comparison to the aldehyde surfaces, native surfaces did not retain protein to any significant degree, and oxidized. TEOS, and triaminopropylsilylatcd surfaces showed merit in applications based upon a reversible association. Protein binding and retention was markedly influenced by mesoscale topology in the absence of covalent surfaceprotein interactions
Effects of Theophylline on Anesthetized Malignant Hyperthermia-Susceptible Pigs
Background. Theophylline was shown to induce contracture development in porcine malignant hyperthermia (MH) susceptible (MHS) skeletal muscles in vitro. The purpose of the current study was to investigate the in vivo effects of theophylline in MHS and MH normal (MHN) swine. Methods. MH-trigger-free general anesthesia was performed in MHS and MHN swine. Theophylline was administered intravenously in cumulative doses up to 93.5 mg·kg−1. The clinical occurrence of MH was defined by changes of central-venous pCO2, central-venous pH, and body core temperature. Results. Theophylline induced comparable clinical alterations in the anesthetized MHS and MHN swine, especially in regard to hemodynamic data. No pig developed hypermetabolism and/or MH according to defined criteria. All animals died with tachycardia followed by ventricular fibrillation. Conclusions. The cumulative theophylline doses used in this study were much higher than doses used therapeutically in humans, as demonstrated by measured blood concentrations. Theophylline is thus not a trigger of MH in genetically determined swine
Optimal Operation and Stabilising Control of the Concentric Heat-Integrated Distillation Column
The Journal of Microelectronic Research
https://scholarworks.rit.edu/meec_archive/1013/thumbnail.jp
Permeability Prediction in Tight Carbonate Rocks using Capillary Pressure Measurements
The prediction of permeability in tight carbonate reservoirs presents ever more of a challenge in the hydrocarbon industry today. It is the aim of this paper to ascertain which models have the capacity to predict permeability reliably in tight carbonates, and to develop a new one, if required. This paper presents (i) the results of laboratory Klinkenberg-corrected pulse decay measurements of carbonates with permeabilities in the range 65 nD to 0.7 mD, (ii) use of the data to assess the performance of 16 permeability prediction models, (iii) the development of an improved prediction model for tight carbonate rocks, and (iv) its validation using an independent data set. Initial measurements including porosity, permeability and mercury injection capillary pressure measurements (MICP) were carried out on a suite of samples of Kometan limestone from the Kurdistan region of Iraq. The prediction performance of sixteen different percolation-type and Poiseuille-type permeability prediction models were analysed with the measured data. Analysis of the eight best models is included in this paper and the analysis of the remainder is provided in supplementary material. Some of the models were developed especially for tight gas sands, while many were not. Critically, none were developed for tight gas carbonates. Predictably then, the best prediction was obtained from the generic model and the RGPZ models (R2 = 0.923, 0.920 and 0.915, respectively), with other models performing extremely badly. In an attempt to provide a better model for use with tight carbonates, we have developed a new model based on the RGPZ theoretical model by adding an empirical scaling parameter to account for the relationship between grain size and pore throat size in carbonates. The generic model, the 28 new RGPZ Carbonate model and the two original RGPZ models have been tested against independent data from a suite of 42 samples of tight Solnhofen carbonates. All four models performed very creditably with the generic and the new RGPZ Carbonate models performing well (R2 = 0.840 and 0.799, respectively). It is clear from this study that the blind application of conventional permeability prediction techniques to carbonates, and particularly to tight carbonates, will lead to gross errors and that the development of new methods that are specific to tight carbonates is unavoidable
The annihilation decay B_c \to eta' l \nu
We first investigate the semileptonic annihilation decay B_c \to \eta' l\nu
in QCD. We find that the momentum distribution is peaked within its
small recoil region due to the loop effects. The branching ratio is estimated
to be for , which is
accessible at CERN LHC.Comment: Typo corrected. To be published in PR
Espejo in the Big Bend
Research paper written by Florian A. Kolodzie for a History class at Marfa High School on January 19, 1948. The paper is about the Spanish exploreres, especailly Antonio de Espejo, in the Big Bend area of Texas
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