Effects of high energy radiation on the mechanical properties of epoxy/graphite fiber composites

Studies on the effects of high energy radiation on graphite fiber reinforced composites are summarized. Studies of T300/5208 and C6000/PMR15 composites, T300 fibers and the resin system MY720/DDS (tetraglycidyl-4,4'-diaminodiphenyl methane cured with diaminodiphenyl sulfone) are included. Radiation dose levels up to 8000 Mrads were obtained with no deleterious effects on the breaking stress or modulus. The effects on the structure and morphology were investigated using mechanical tests, electron spin resonance, X-ray diffraction, and electron spectroscopy for chemical analysis (ESCA or X-ray photoelectron spectroscopy). Details of the experiments and results are given. Studies of the fracture surfaces of irradiated samples were studied with scanning electron microscopy; current results indicate no differences in the morphology of irradiated and control samples

Writer identification by a combination of graphical features in the framework of old handwritten music scores

Descripció del recurs: el 23 de febrer de 201

Review of lessons learned after five years of shallow water autonomous underwater vehicles (AUV) operations

The Unidad de Tecnología Marina (UTM) acquired in 2010, due to the wide scientific requirement to obtain high quality images of the seafloor, a couple of AUV´s for shallow waters applications with the aim to support marine research operations in coastal waters. The vehicles has been used as a routine science vehicle but also for technical development. During these years a valuable experience has been gained for future operation on either, coastal and open waters with new and more performant platforms.Peer Reviewe

The current state and development of budget transparency

Treball Final de Grau en Finances i Comptabilitat. Codi: FC1049. Curs acadèmic 2013-2014The state of budget transparency at a global level is not satisfactory, according to the results of the Open Budget Survey 2012. It found that the average of the 100 countries surveyed is 43 out of 100. Studies show that there have been improvements in recent years, but that progress is very slow. Public participation in the budget process in most countries is scarce, while legislatures and Supreme Audit Institutions (SAIs) are generally strong, but sometimes suffer from deficiencies or limitations in their tasks. International organizations have developed codes of good practice for transparency and various studies have shown it benefits budget transparency in countries. Thanks to these, there has been a global consensus to promote budget transparency and improve governance, participation of civil society and economic development

Effects of high energy radiation on the mechanical properties of epoxy/graphite fiber reinforced composites

Publications and theses generated on composite research are listed. Surface energy changes of an epoxy based on tetraglycidyl diaminodiphenyl methane (TGDDM)/diaminodiphenyl sulfone (DDS), T-300 graphite fiber and T-300/5208 (graphite fiber/epoxy) composites were investigated after irradiation with 0.5 MeV electrons. Electron spin resonance (ESR) investigations of line shapes and the radical decay behavior were made of an epoxy based on tetraglycidyl diaminodiphenyl methane (TGDDM)/diaminodiphenyl sulfone (DDS), T-300 graphite fiber, and T-300/5208 (graphite fiber/epoxy) composites after irradiation with Co(60) gamma-radiation or 0.5 MeV electrons. The results of the experiments are discussed

Effects of high energy radiation on the mechanical properties of epoxy graphite fiber reinforced composites

The effects of high energy radiation on mechanical properties and on the molecular and structural properties of graphite fiber reinforced composites are assessed so that durability in space applications can be predicted. A listing of composite systems irradiated along with the maximum radiation dose applied and type of mechanical tests performed is shown. These samples were exposed to 1/2 MeV electrons

Noise propagation in "Escherichia coli's" regulatory network

The ability to regulate gene expression allows bacteria to grow under diverse conditions, often involving large regulatory networks. As gene expression is an inherently stochastic process, accurate regulation will only be achieved if the molecules involved in the process adapt perfectly to the different conditions and show low noise themselves. In Escherichia coli it has been reported that high noise promoters are characterized by containing a large number of regulatory binding sites in their sequences and that noise propagation from the regulators to their targets is explaining the elevated noise levels. This suggests that regulation and noise are intimately coupled. However, little is known about this association or even how noise levels vary in response to changes in the environment. The work presented in this thesis aims at elucidating to what extent noise and gene regulation are coupled. We have quantified the variation in genome-wide transcriptional noise across 8 diverse growth conditions in Escherichia coli using flow cytometry and high-throughput microscopy. In summary, we find a growth-rate dependent lowerbound on noise mainly exhibited by constitutive promoters. Individual regulated promoters show complex behaviours in terms of changes in mean and noise across conditions, and condition-dependent expression noise shaped by noise propagation from transcription factors. Using a simple linear model we identify a set of TFs that contribute to condition-specific and condition-independent noise propagation. The overall correlation structure of genome-wide expression properties uncovers that genes are organized along two principal axes, with the first one sorting genes by their mean expression and evolutionary rate, and the second one by their expression noise, number of regulatory inputs and expression plasticity. Overall, the results of the thesis show clear evidence that noise and regulation are intimately linked due to noise propagation from regulators to their targets, and that this association has evolved independently of a promoter's expression level or evolutionary rate in its coding region

Boolean Operator

https://openscholarship.wustl.edu/bcs/1413/thumbnail.jp