scholarly journals Impact of Crystalline Orientation on the Switching Field in Barium Titanate Using Piezoresponse Force Spectroscopy

2014 ◽  
Vol 1652 ◽  
Author(s):  
Nikhil K. Ponon ◽  
Daniel J. R. Appleby ◽  
Erhan Arac ◽  
Kelvin S. K. Kwa ◽  
Jonathan P. Goss ◽  
...  
Keyword(s):  
Electric Field ◽  
Phase Change ◽  
Crystal Orientation ◽  
Force Spectroscopy ◽  
Ferroelectric Domain ◽  
Switching Field ◽  
The Impact ◽  
Non Destructive ◽  
Domain Level

ABSTRACTUnderstanding crystal orientation at the ferroelectric domain level, using a non destructive technique, is crucial for the design and characterization of nano-scale devices. In this study, piezoresponse force spectroscopy (PFS) is used to identify ferroelectric domain orientation. The impact of crystal orientation on the switching field of ferroelectric BaTiO3 is also investigated at the domain level. The preferential domain orientations for BaTiO3 thin films prepared by pulsed laser deposition (PLD) in this study are [001], [101] and [111]. They have been mapped onto PFS spectra to show three corresponding switching fields of 460, 330 and 120 kV/cm respectively. In addition, the electric field at which the enhanced piezoresponse occurs was found to vary, due to a phase change. The polarization reversal occurs via a 2-step process (rotation and switching) for [101] and [111] orientations. The piezoresponse enhancement is absent for the [001] (pure switching) domains. The results demonstrate that an electric field induced phase change causes the [101] and [111] domains to reverse polarization at a lower field than the [001] domain.

Electrical Characterization of E7 Liquid Crystal Molecules under the Impact of an External Electric Field (THz): A Theoretical approach

2020 ◽  
Vol 15 (2) ◽  
pp. 95-101
Keyword(s):  
Liquid Crystal ◽  
Electric Field ◽  
Order Parameter ◽  
Optical Switching ◽  
Rapid Change ◽  
Electrical Characterization ◽  
Optical Switching Devices ◽  
The Impact ◽  
Orientation Of Molecules

In this work, different parameters of E7 liquid crystal (LC) have been calculated under the influence of an electric field in THz frequency. The E7 LC parameters have positive as well as negative values of order parameter and birefringence under the influence for an electric field. The director angle of E7 LC shows fast fluctuations above the angle θ=45° and due to rapid change in the orientation of molecules, fast electro-optical switching devices based on E7 LC can be designed. The refractive index of the E7 LC maintains stability in THz frequency.

scholarly journals Sonic and Impact Test for Structural Assessment of Historical Masonry

2019 ◽  
Vol 9 (23) ◽  
pp. 5148 ◽  
Author(s):  
Alessandro Grazzini
Keyword(s):  
Impact Test ◽  
Structural Parameters ◽  
Historical Masonry ◽  
2016 Amatrice Earthquake ◽  
The Impact ◽  
Santa Maria ◽  
Non Destructive ◽  
Non Destructive Techniques

Diagnostics is a very important tool of knowledge in the field of historical buildings. In particular, non-destructive techniques allow to deepen the study of the mechanical characteristics of the historical walls without compromising the artistic value of the monumental building. A case study of the use of sonic and impact tests was described, performed using the same instrumented hammer, for the characterization of the masonry walls at the Sanctuary of Santa Maria delle Grazie at Varoni, one of the churches damaged in the 2016 Amatrice earthquake. Sonic tests showed the presence of a discontinous masonry texture, as well as confirming the ineffectiveness of the strengthening work made by injections of lime mortar. The impact test allowed us to obtain the elastic modulus of the omogeneous stones of the masonry. The results obtained from the non-destructive techniques were confirmed by the flat jacks test carried out on the building, confirming the great potential of the non-destructive diagnostics suitable for analyzing important structural parameters without affecting the preservation of historical masonry structures.

scholarly journals Chemistry for Audio Heritage Preservation: A Review of Analytical Techniques for Audio Magnetic Tapes

Heritage ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 1551-1587
Author(s):  
Federica Bressan ◽  
Richard L. Hess ◽  
Paolo Sgarbossa ◽  
Roberta Bertani
Keyword(s):  
Analytical Techniques ◽  
Video Data ◽  
Cultural Resources ◽  
Chemical Identification ◽  
Heritage Preservation ◽  
The World ◽  
Instrumental Approaches ◽  
The Impact ◽  
Non Destructive

Vast and important cultural resources are entrusted to magnetic tape around the world, but they are susceptible to degradation, which may lead to severe replay problems. Audio magnetic tapes are complex and multicomponent devices containing organic compounds and metal systems, which can be potential catalysts for many degradative reactions in the presence of water, light, or heating. The aim of this review is to collect the literature concerning the analytical determinations and instrumental approaches that can achieve the chemical identification of the components in the tape and the degradation state. Thus, a combination of destructive (such as acetone extraction) and non-destructive techniques (such as ATR FTIR spectroscopy) have been proposed, together with SEM, ESEM, XRD and TGA analyses to assess the chemical and physical characterization of the tape with the purpose to individualize restoration treatments and optimize conditions for preservation. The impact of the studies reviewed in this paper may go beyond audio, being potentially relevant to video, data, instrumentation, and logging tapes.

Characterization of the Degradation Processes in SiO2-Si Structure by Means of Electrolyte-Insulating-Semiconductor Systems

1993 ◽  
Vol 309 ◽  
Author(s):  
S.A. Bota ◽  
J.R. Morante ◽  
A.P. Baraban ◽  
V.V. Bulavinov ◽  
P.P. Konorov
Keyword(s):  
Electric Field ◽  
Hole Injection ◽  
Insulating Layer ◽  
Oxide Breakdown ◽  
Structure Degradation ◽  
Injection Zone ◽  
The Stability ◽  
Non Destructive

AbstractA non destructive method to characterize the properties of SiO2 films in SiO2-Si structures and analyze their variations under different external actions is presented and discussed. The method is based on the properties of the Electrolyte-SiO2 contact under polarization which allows us to study the SiO2 film in different injection conditions, in a hole injection zone, in a predominant electron injection zone, and finally, in a region of electron heating as a result of the electric field action before to reach the oxide breakdown. Moreover, using this method, higher electric field values than in the metal-SiO2-Si system can be applied.The characterization of hole traps, electron traps and defect precursors states in SiO2 films are carried out as well as their evolution and influence on the SiO2-Si structure degradation and electrical behaviour. Results measured on SiO2-Si structures obtained from different technological processes and submitted to different treatments are reported in order to discuss the possibilities of this method as a power tool to assess the stability and quality of insulating layer on semiconductors.

scholarly journals Elastic Properties Estimation of Masonry Walls through the Propagation of Elastic Waves. An Experimental Investigation

2021 ◽  
Vol 11 (19) ◽  
pp. 9091
Author(s):  
Jacopo Marazzani ◽  
Nicola Cavalagli ◽  
Vittorio Gusella
Keyword(s):  
Elastic Waves ◽  
Structural Parameters ◽  
Masonry Walls ◽  
Artistic Value ◽  
Masonry Material ◽  
Historical Masonry ◽  
The Impact ◽  
Propagation Of Elastic Waves ◽  
Non Destructive

Structural identification is one of the most important steps when dealing with historic buildings. Knowledge of the parameters, which define the mechanical properties of these kinds of structures, is fundamental in preparing interventions aimed at their restoration and strengthening, especially if they have suffered damage due to strong events. In particular, by using non-destructive techniques it is possible to estimate the mechanical characteristics of load-bearing structures without compromising the artistic value of the monumental buildings. In this paper, after recalling the main theoretical aspects, the use of elastic waves propagation through impact tests for the characterization of the masonry walls of a monumental building is described. The impact test allowed us to estimate the elastic characteristics of the homogeneous solid equivalent to masonry material. This confirms the great potential of the non-destructive diagnostics suitable for analyzing important structural parameters without affecting the preservation of historical masonry structures.

Characterization of Carbonatation Rate of Alkali-Activated Blast Furnace Slag in Various Environments

2021 ◽  
Vol 325 ◽  
pp. 40-46
Author(s):  
Richard Dvořák ◽  
Petr Hrubý ◽  
Libor Topolář
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Destructive Testing ◽  
Time Intervals ◽  
Impact Echo ◽  
The Impact ◽  
Non Destructive ◽  
Furnace Slag ◽  
Alkali Activated

Carbonatation represents one of the potential degradation processes whose can negatively affect the service life of constructions based on the inorganic binders. The carbonatation depth of the constructions when exposed to various environments is significantly dependent on the existing conditions. The most crucial parameters are the partial pressure of carbon dioxide and humidity. There were selected four environments for the deposition of samples made of the alkali-activated blast furnace slag mortars (exterior, interior, water and CO2 chamber) in this study. These types of environments guarantee the variation of desired parameters influencing the carbonatation rate. The progress of carbonatation was evaluated with a selected technique in time intervals of 28; 56 and 84 days of the sample's exposition to the selected environments. The characterization was done using the destructive techniques (compressive and flexural strength, phenolphthalein method) as well as the non-destructive one like the Impact-Echo or the Ultrasound time passage measurement. The combination of these techniques allows to determine and evaluate the progress of carbonation without the destructive testing of the samples which is necessary for the real applications of these materials.

scholarly journals The Influence of Sensitivity Field of Dual Transducer Probes on Accuracy of Discontinuity Sizing and Evaluation in Terms of Testing of Forgings According to EN 10228-3

2016 ◽  
Vol 61 (3) ◽  
pp. 1677-1682
Author(s):  
R. Kaczmarek ◽  
K. Kaczmarek
Keyword(s):  
Significant Influence ◽  
Ultrasonic Testing ◽  
Sensitivity Distribution ◽  
Moving Direction ◽  
The Impact ◽  
Non Destructive ◽  
Transducer Probe ◽  
Sensitivity Field

Abstract The article presents results of research on the impact of sensitivity distribution of double transducer probes, which are often used in non-destructive ultrasonic testing of components such as forgings. Distribution of sensitivity measured in two orientations, parallel and perpendicular to the plane of separation of a double transducer probe has been tested and analyzed. A significant influence of orientation of a probe on echo envelope of an artificial point discontinuity has been studied. It has revealed great differences in length and shape of an echo envelope, depending on a type of probe and orientation of a probe separation plane to the moving direction. Eventually, the analysis of practical consequences of dual transducer probes usage for characterization of a type, dimensioning and evaluation of internal discontinuities, in accordance to the methodology specified in EN 10228, has been conducted.

The Analyses of Learning Strategies in English as a Second Language: Theoretical Classification and Measurement Test

2020 ◽  
Vol 4 (2) ◽  
pp. 118-129
Author(s):  
Asti Gumartifa ◽  
◽  
Indah Windra Dwie Agustiani
Keyword(s):  
Language Learning ◽  
Learning Outcomes ◽  
Learning Strategies ◽  
Learning Process ◽  
English Learners ◽  
English Language ◽  
Point Of View ◽  
Effective Learning ◽  
The Impact

Gaining English language learning effectively has been discussed all years long. Similarly, Learners have various troubles outcomes in the learning process. Creating a joyful and comfortable situation must be considered by learners. Thus, the implementation of effective learning strategies is certainly necessary for English learners. This descriptive study has two purposes: first, to introduce the classification and characterization of learning strategies such as; memory, cognitive, metacognitive, compensation, social, and affective strategies that are used by learners in the classroom and second, it provides some questionnaires item based on Strategy of Inventory for Language Learning (SILL) version 5.0 that can be used to examine the frequency of students’ learning strategies in the learning process. The summary of this study explains and discusses the researchers’ point of view on the impact of learning outcomes by learning strategies used. Finally, utilizing appropriate learning strategies are certainly beneficial for both teachers and learners to achieve the learning target effectively.

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