Search results for "device"
showing 10 items of 1286 documents
A simplified description of viscoelastic behavior of polymers as illustrated with biaxially-oriented poly(ethylene terephthalate)
1978
A rheological model of solid polymers is proposed. Its mechanical analog is a parallel of a linear spring and a Maxwell element with variable viscosity. The viscosity of the dashpot is allowed to change with stress both directly, by an Eyring-type mechanism, and through free volume changes according to the Doolittle equation. Predictions of the model reproduce many of the features shown, especially after yielding, by constant velocity stress-strain, stress-relaxation and creep data taken at room temperature on biaxially-oriented poly(ethylene terephthalate) over a wide range of loading rates.
Novel benzofulvenes-based polymers: Characterization and employment in flexible electrochromic devices
2014
Benzofulvenes-based monomers have been synthesized for the first time and have been polymerized by means of electrochemical methods onto different electrodic materials. Morphological investigation has been performed by using SEM; electrical and optical properties have been studied by means of both cyclic voltammetry, optical absorption and spectroelectrochemical techniques. Finally, solid state electrochromic devices have been fabricated. They have displayed high optical contrast.
Osmotic pressure, atomic pressure and the virial equation of state of polymer solutions: Monte Carlo simulations of a bead-spring model
1994
A recently introduced coarse-grained model of polymer chains is studied analyzing various contributions to the pressure as obtained from the virial theorem as a function of chain length N, temperature T and density ϕ. The off-lattice model of the polymer chains has anharmonic springs between the beads, but of finite extensibility, and the Morse-type interaction between beads is repulsive at very short distances and attractive at intermediate distances. Solvent molecules are not explicitly included. It is found that the covalent forces along the chain (modelled by the spring potentials) contribute a negative term to the pressure, irrespective of temperature, which vanishes linearly in ϕ as ϕ…
A Novel Zeolite-Induced Population of a Planar Viologen Conformation. New Viologen Charge Transfer Complexes and Alkene/Viologen/Zeolite Arrays
2004
A rare example of a novel zeolite-induced conformational change and a mechanism for this process are suggested in order to rationalize an unexpected spontaneous intrazeolite reduction observed during preparation of a new viologen (MQ2+)-doped zeolite (NaY). In addition, the formations of six new alkene/viologen/ zeolite charge transfer (CT) arrays using NaMQY and the previously reported NaMVY are also reported. The binding constants between MQ2+ and MV2+ and 2,3-dimethyl-2-butene (TME) were determined using the Benesi-Hildebrand approach, and the stabilities of these CT complexes are compared to their intrazeolite analogue.
<title>Cerium-containing counter electrodes for transparent electrochromic devices</title>
1997
Films of Me-Ce oxide (Me: Ti, Zr, Sn, W) and of Ni-Ce hydroxide were produced by reactive magnetron co-sputtering. Li intercalation in Me-Ce oxide, and H exchange in Ni-Ce hydroxide, were accomplished electrochemically. Electrochromism was quenched in proportion with the Ce content in Me-Ce oxide. Films of Zr-Ce (and to some extent Ti-Ce) oxide were able to serve as fully transparent counter electrodes, of much interest for transparent electrochromic devices. In Ni-Ce hydroxide, the Ce addition enhanced the capacity for charge exchange.
A cross-sectional study on smartphone uses among pregnant women attending childbirth classes in the Metropolitan Area of Palermo, Italy: The Stop-Pho…
2022
Background: Prevalence of mobile device addiction has increased over the years; both women and men have assimilated the mobile phone as a central component of their personal existence: integrating it into their lifestyle or becoming so dependent on it that life without it has become unimaginable. Smartphones generate radio-frequency electromagnetic fields. While short-term exposure in adults was considered quite safe, effects of long-term exposure or exposure during pregnancy on fetuses or during breastfeeding on newborns are not well studied yet. The objective of the present study was to investigate the prevalence and usage characteristics of smartphones among a sample of pregnant women, a…
Mākslinieciskās izteiksmes līdzekļi rakstos par ekonomiku
2022
Šajā bakalaura darbā tiek pētīts stilistisko ierīču lietojums un to nolūks The Economist laikrakstu rakstos par ekonomiku. Šajā darbā izmantotā pētījuma metode ir diskursa analīze, balstīta uz Galperina (1977) stilistisko ierīču klasifikāciju. Darbā apskatīta stilistikas kā nozares izcelsme, attīstība un klasifikācija. Pētījuma rezultāti liecina, ka žurnālistikā par ekonomiku tiek izmantotas dažādas stilistikās ierīces, un visbiežāk izmantotās stilistiskās ierīces kā spriedze, citāti, metaforas un aliterācija. Papildus tam tiek secināts, ka tekstā esošie līdzekļi palīdz rakstos izmantotajā valodā izcelt dramatisku efektu, kā arī sniegt tekstam papildus informāciju.
Solid-state-biased coherent detection of ultra-broadband terahertz pulses
2017
Significant progress in nonlinear and ultrafast optics has recently opened new and exciting opportunities for terahertz (THz) science and technology, which require the development of reliable THz sources, detectors, and supporting devices. In this work, we demonstrate the first solid-state technique for the coherent detection of ultra-broadband THz pulses (0.1-10 THz), relying on the electric-field-induced second-harmonic generation in a thin layer of ultraviolet fused silica. The proposed CMOS-compatible devices, which can be realized with standard microfabrication techniques, allow us to perform ultra-broadband detection with a high dynamic range by employing probe laser powers and bias v…
Kohēzija biznesa runās
2018
Šis bakalaura darbs pēta kohēzijas līmeni Maska un Mejas un Abes runās par komercdarbību. Darba mērķis ir izpētīt kohēzijas līdzekļu lietojumu runās par komercdarbību. Kā pētijuma metodes darbā izmantots literatūras apskats par dažādiem publicētajiem avotiem par leksisko un gramatisko kohēziju un biznesa diskursu, kā arī biežuma analīze. Leksiskās kohēzijas, atsauces, un saikļa klātbūtne tika analizēti trīs runās un trīs runās struktūras daļās. Analīzes rezultāti parādīja, ka iepriekš minēto kohēzijas līdzekļu izmantošanas biežums ir diezgan vienāds. Tomēr var secināt, ka saiklis ir visizplatītākais kohēzijas līdzeklis analizētajās runās par komercdarbību.
On-line quizzes to evaluate comprehension and integration skills
2016
[EN] This work demonstrates the use of a 2.0 tool, namely, Socrative, to evaluate one of the cross-curricular competences indicated by the Universitat Politècnica de València, specifically, comprehension and integration. It has been applied to the courses in different areas: sciences, engineering and languages. As part of its implementation, activities were proposed that could be done at the beginning, during or at the end of the class to, on the one hand, help students acquire the knowledge associated with the course(s), and on the other, gather evidence that demonstrates acquisition of said competence. The results show a high level of satisfaction by the students with the use of the Socra…