Tesi: "Textile Electrode"

1

Backe, Carin. "Enhancing textile electrode performance : Regulating moisture management through textile structure". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12389.

Testo completo

Abstract (sommario):

The medical field has been a part of the smart textile area for quite some time. With time come technological advancement and the two fields converge on more and more areas. One such area is that of using textile electrodes, textrodes, for measuring bioelectrical activity, such as heart rate for ECG analysis. There are many components that make for a successful textile electrode and though many studies have been made in the subject there are several aspects that still are difficult. By using textile electrodes the problem with skin irritation from electrolyte gels, commonly used for conventional electrodes, is avoided, however dry textrodes create disturbances in the output signal (heart rate) while subjected to movement and internal dimensional changes. The addition of moisture to a textrode has shown to decrease these intermittent disturbances but the knowledge about fundamental textile structural influence in the matter has not been fully investigated. This study investigates a flat, a 2-thread fleece and an open structure, and their relation to moisture both as textile structures and as textrodes. This way the possibilities of utilising moisture to increase performance in a textrode purpose can be examined and to what extent the textile structure plays a part in that exploitation. The material composition of textile structures also affects their properties The introduction of assistive materials, polyester and viscose, into the Shieldex (conductive yarn) structures is done to test core moisture management properties such as surface tension, absorption and moisture content, and correlate them to electrical properties necessary for textrode function. In the end the gap between textile structure and end product in form of a textrode is closed as the impedance and microclimate of the textrodes are studied. This is mainly to tie together the fundamental textile structures with a complex textile construction. In conclusion the complexity is also confirmed as structural, materialistic and external influences has an impact on the results. The influence of moisture on lowered resistance and impedance in the structures is confirmed but the impact of textile structure can also be seen. The 2-thread fleece and open structures often has a more positive impact on results and therefore has the possibility of enhancing performance of a textrode for bioelectrical signal monitoring. With these results a more effective way of producing long-lasting, patient-friendly, textrodes can be derived and in the future lead to better care in the medical areas.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Taji, Bahareh. "Reconstruction of ECG Signals Acquired with Conductive Textile Eletrodes". Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/26303.

Testo completo

Abstract (sommario):

Physicians’ understanding of bio-signals, measured using medical instruments, becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments’ readings exactly reflect what is happening in the patient’s body so that the detected signal is the real one or at least as close to the real in-body signal as possible and carries all of the appropriate information. This is such an important issue that sometimes physicians use invasive measurements in order to obtain the real bio-signal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction,” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this research, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. In order to evaluate the performance of the device, we use it to measure ECG and apply conductive textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results. Next, we propose a method to reconstruct the ECG signal from the signal we detected with our device with respect to the interface characteristics and their relation to the detected ECG. The interface in this study is the skin-electrode interface for conductive textiles. In the last stage of this work, we explore the effects of pressure on skin-electrode interface impedance and its parametrical variation.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Euler, Luisa. "Impedance and Stimulation Comfort of Knitted Electrodes for Neuromuscular Electrical Stimulation (NMES) : Influence of electrode construction and pressure application to the electrode". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-23896.

Testo completo

Abstract (sommario):

Neuromuscular electrical stimulation (NMES) is a modality of electrotherapy which is aiming to restore and improve muscle function by injecting small levels of current into the muscle using different types of electrodes. Advantages are seen in using textile electrodes which can be integrated into wearables. Previous research has been done for the development of textile stimulation electrodes. However, the focus has not been on the electrode construction itself. Therefore, the influence of electrode construction parameters of knitted electrodes as well as of the electrode condition, i.e. wet or dry, on the skin-electrode impedance and on the perceived stimulation comfort were analysed. Further, the application of pressure to the electrode was investigated. It was found that the electrode condition is the most important parameter for the electrode performance as a wet electrode showed a lower impedance and an improved stimulation comfort with a better skin contact. Followed by this, the pressure was the second most important factor, especially for dry electrodes. A higher pressure reduced the skin-electrode impedance and improved the skin contact in dry condition. Nevertheless, dry electrodes with a high applied pressure still performed worse than wet electrodes. Regarding the electrode design, the most important factor was the electrode size. A bigger size reduced the impedance. Nevertheless, for the application in NMES, a smaller electrode size is to be preferred as it improved the stimulation selectivity and thus, a lower NMES level was required to induce a plantarflexion without affecting the stimulation comfort. The other investigated construction parameters (binding, yarn density, shape) only showed minor influences on the electrode performance. Therefore, the possibilities of applying pressure to the electrode to improve the performance of dry textile electrodes should be further investigated.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Lee, Graham. "An investigation into the feasibility of the integration of microwave circuitry into a woven textile". Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13560.

Testo completo

Abstract (sommario):

To investigate the integration of a textile antenna into a woven substrate at the point of production. The antenna was to have the characteristics of a conventional fabric interms of the handle and drape.

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Jafari, Ehsan. "Novel Approaches in Functional Electrical Stimulation for Rehabilitation : Development, Analysis, and Optimization". Electronic Thesis or Diss., Lyon, École normale supérieure, 2024. http://www.theses.fr/2024ENSL0008.

Testo completo

Abstract (sommario):

Cette thèse vise à surmonter les limites de la stimulation électrique fonctionnelle (SEF) grâce à une approche novatrice et multimodale, qui explore aussi bien le développement d'électrodes transcutanées, que les stratégies de stimulation, ainsi que les perspectives d'optimisation biomécanique. Une première étude compare l'efficacité des électrodes textiles intégrées dans les vêtements, utilisées avec une lotion hydratante, par rapport aux électrodes conventionnelles à hydrogel auto-adhésives. L'évaluation porte sur des aspects tels que le confort de la stimulation, la cohérence temporelle, l'efficacité, et le comportement de l'impédance électrique dans des conditions isométriques. Les participants à l'étude ont effectué des tests avec les deux types d'électrodes, nous permettant d’évaluer des paramètres tels que les intensités minimales générant une contraction musculaire ou une sensation de brûlure, et l'intensité maximale tolérable. Les résultats indiquent que les électrodes textiles, lorsqu'elles sont complétées par une lotion, sont comparables aux électrodes à hydrogel en termes de confort, de consistance et d'efficacité. Une seconde étude examine l'impact de la stimulation séquentielle distribuée spatialement (SSDS) à intensité moyenne ou haute, sur la réduction de la fatigue chez les personnes souffrant d'une lésion de la moelle épinière. L'étude révèle que la SSDS est significativement plus efficace à moyenne intensité. En outre, une étude de cas a été réalisée pour évaluer les différences de puissance et fatigue produites lors d’un exercice de cyclisme électrostimulé utilisant la SSDS. Il s'agissait de stimuler les quadriceps de quatre participants paraplégiques moteurs complets. L’étude a montré que la SSDS génère non seulement plus de puissance que la configuration à une seule électrode, mais également sans avoir d'impact significatif sur le niveau de fatigue. La dernière étude se concentre sur l'optimisation des propriétés biomécaniques du cyclisme et de la séquence de stimulation afin d'obtenir une puissance de sortie maximale avec une stimulation appliquée minimale. Un modèle musculaire précis et facile à utiliser, associé à des fonctions de transfert de couple basées sur le Jacobien, a été adopté pour déterminer la position assise optimale, l'angle du tronc, la longueur du bras de manivelle et les séquences de stimulation. En outre, l'impact de la fonction force-vitesse du muscle sur la détermination de la position assise optimale et des séquences de stimulation a été étudié. Les modèles de simulation ont montré un effet insignifiant de la fonction force-vitesse sur la position assise optimale de six sujets sains simulés. Nous pensons que les contributions de cette thèse augmenteront l'efficacité de la SEF en tant que technique de rééducation fonctionnelle
This thesis aims to overcome the limitations of functional electrical stimulation (FES) through a multifaceted novel approach that concentrates on developing transcutaneous electrodes, stimulation strategies, and biomechanical optimization perspectives. The first study investigates the effectiveness of garment-embedded textile electrodes, used with a moisturizing lotion, against conventional self-adhesive hydrogel electrodes. The evaluation encompasses aspects such as stimulation comfort, temporal consistency, efficiency, and electrical impedance behavior under isometric conditions. Participants in the study underwent tests with both electrode types, evaluating parameters like motor threshold intensity, burning sensation intensity, and maximum tolerable intensity. The results indicate that textile electrodes, when supplemented with lotion, perform comparably to hydrogel electrodes in terms of comfort, consistency, and efficiency. The next study investigates the impact of spatially distributed sequential stimulation (SDSS) at high and moderate intensities on reducing fatigue in individuals with spinal cord injury. The study, focusing on the quadriceps muscle group, found that moderate-intensity SDSS is significantly more effective than high-intensity SDSS. Additionally, a case study was conducted to assess the differences in power generation and fatigue levels between FES cycling using SDSS and a single electrode setup. This involved stimulating the paralyzed quadriceps muscles of four participants over multiple days during motor-assisted FES cycling. The results indicated that SDSS not only generated more power compared to the single electrode setup but did so without significantly impacting fatigue levels. The last study focuses on the optimization of the cycling biomechanical properties and stimulation pattern to achieve maximum output power with minimum applied stimulation. In this work, an easy-to-use and precise muscle model in conjunction with Jacobian-based torque transfer functions was adopted to determine the optimal seating position, trunk angle, crank arm length, and stimulation intervals. Furthermore, the impact of muscle force-velocity factor in finding the optimal seating position and stimulation intervals was investigated. The simulation models showed the trivial effect of the force-velocity factor on the resulting optimal seating position of six healthy simulated subjects. We believe that the contributions of this thesis will increase the efficacy of FES as a rehabilitation technique

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Ekhagen, Sebastian. "Stability of electron acceptor materials for organic solar cells : a work function study of C60/C70 derivatives and N2200". Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-72727.

Testo completo

Abstract (sommario):

Thin films of the fullerenes PC60BM and PC70BM and the non-fullerene N2200, three popular electron acceptor materials in organic photovoltaics, have been studied, using both the Kelvin probe method as well as ultraviolet photoelectron spectroscopy. With these methods the work function was measured, as well as the highest occupied molecular orbital (HOMO) onset. Additionally band bending effects were studied by illuminating the samples while measuring the work function with the Kelvin probe so called surface photovoltage. Sample of each material was exposed to either air and simulated sunlight or N2 and simulated sunlight, for different length of time, to observe how the materials work function evolves after exposure to the different conditions. It was observed that, as expected from previous studies, that PC60BM was less photo-stable than PC70BM. Additionally, the work function of PC60BM changed significantly by storage in N2. Each material after exposure for 24h to air and light, was annealed and measured with the Kelvin probe. A restoring effect was observed, for the non-fullerene material N2200. All three materials developed an increasing surface photovoltage, which suggest increased band bending, when exposed to air and light, indicating that due phot-oxidization, charges are redistributed at the surface of the film. The fullerenes showed a larger surface photovoltage effect than the non-fullerene materials. A difference between the work function values obtained from the Kelvin probe method and the ultraviolet photoelectron spectroscopy could be seen, however the exact reason for this couldn't be isolated within this thesis, but was discussed.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Marquez, Juan Carlos. "On the Feasibility of Using Textile Electrodes for Electrical Bioimpedance Measurements". Licentiate thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-3607.

Testo completo

Abstract (sommario):

The application of textile electrodes has been widely studied for biopotential recordings,especially for monitoring cardiac activity. Commercially available applications, such as theAdistar T-shirt and the Numetrex Cardioshirt, have shown good performance for heart ratemonitoring and are available worldwide.Textile technology can also be used for electrical bioimpedance (EBI) spectroscopymeasurements in home and personalized health monitoring applications, however solid basicresearch about the measurement performance of the electrodes must be performed prior to thedevelopment of any textile-enabled EBI application.This research work studies the performance of EBI spectroscopy measurements whenperformed with textile electrodes. An analysis using an electrical circuit equivalent model andexperimental data obtained with the Impedimed spectrometer SFB7 was carried out. Theexperimental study focused on EBI spectroscopy measurements obtained with different types oftextile electrodes and in different measurement scenarios. The equivalent model analysis focusedon the influence of the electrode polarization impedance Zep on the EBI spectroscopymeasurements in the frequency range of 3 kHz to 500 kHz.The analysis of the obtained complex EBI spectra shows that the measurements obtainedwith textile electrodes produce constant and reliable EBI spectra. The results also indicate theimportance of the skin-electrode interface in EBI spectroscopy measurement.Textile technology, if successfully integrated, may enable the performance of EBIspectroscopy measurements in new scenarios, which would allow the generation of novel,wearable, or textile-enabled applications for home and personal health monitoring

Thesis Supervisors: Kaj Lindecrantz and Fernando Seoane

Sponsorship:

Mexican CONACYT

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Jenkins, L. "Development of environmental scanning electron microscopy for textile hydration studies". Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605085.

Testo completo

Abstract (sommario):

The possibility of supporting a saturated water vapour atmosphere together with the presence of liquid water in the Environmental Scanning Electron Microscope (ESEM) presents new opportunities for the observation of water-textile interactions. It is important to understand such interactions because they will affect many manufacturing and performance processes, including dyeing, finishing, comfort and washing behaviour. Control of temperature and pressure conditions surrounding the sample in the ESEM allows the performance of in situ hydration experiments at high magnification and resolution. Many organic materials are very susceptible to the effects of the beam in an electron microscope. Beam specimen interactions will change the nature and therefore behaviour of the sample. Experiments with cellulosic fibres showed that some of the visible signs of damage are identical to those indicating interaction with water. These signs include smoothing of the fibre surfaces, and loss of surface and edge detail. Experiments were performed to investigate the effect of various experimental parameters on the time of onset of damage. From the results of these experiments, conditions were found which delayed the onset of visible damage for 40-50 minutes. Using the damage-free conditions, mounting and hydration techniques were developed which allow the observation of cross-section area increase in fibres as they interact with liquid water. The results obtained for the lyocell fibres chosen for these experiments show good agreement with similar swelling experiments in the optical microscope performed to confirm the temperature independence of swelling at low temperature. The possibility of assessing the effect of packing density on swelling using the same hydration technique has also been investigated, but limitations of the mounting method prevent the acquisition of useful data for this purpose. A method has been developed for the observation of the wetting behaviour of various textile fabrics. It has been shown that the ESEM provides a quick and easy method of comparing the behaviours of sample materials. Ability to interpret the images produced in the microscope depends on a knowledge of wetting processes. Conditions have been found which allow the condensation of water droplets onto individual textile fibres. Initial assessment has been made to determine the suitability of the ESEM micrographs for the measurement of contact angles.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Awad, Hernández Fahmi. "Desafíos de la capa física para el monitoreo y control remoto de pacientes". Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/142483.

Testo completo

Abstract (sommario):

Ingeniero Civil Eléctrico
En la actualidad existe una gran necesidad de monitorear pacientes en forma remota dado que hay capacidades limitadas en centros médicos, tanto de profesionales como de instrumental e insumos. Más allá de esto, respecto al electrocardiograma en particular, se utiliza un método en el cual se coloca doce electrodos en el cuerpo del paciente, además de filtrar los datos con máquinas bastante grandes, lo que se traduce en incomodidad para el sujeto y una maquinaria costosa que puede ser reemplazada. Este trabajo se enfoca en el desarrollo de un sistema de amplificación y filtrado simplificado para un electrocardiograma utilizando el método de Einthoven, y en la implementación de electrodos de una composición química diferente, denominados PEDOT:PSS. Se trabaja con éstos como reemplazo de los comúnmente utilizados dado que son hidrofílicos, lavables y no producen irritación, por lo cual son considerados un avance respecto al ámbito invasivo de la detección. La amplificación sin ruido es una parte crítica en el diseño del circuito, por lo tanto es imperativo obtener el filtrado necesario. Se diseñan circuitos para la inversión de voltaje necesaria, el amplificador y los filtros pasa bajos de 150 Hz, pasa altos de 0.1 Hz y notch de 50 Hz a utilizar. Los resultados obtenidos se pueden organizar de la siguiente forma: inicialmente se obtiene una señal alimentando con 3 y 5 V, con y sin filtro notch, en una prueba con sensores comunes, midiendo con osciloscopio Rigol. Luego se analiza el mismo circuito alimentado con baterías y medido con el DSO Nano V3 y finalmente se examina con un electrodo PEDOT:PSS. Se opta por una alimentación independiente ya que se disminuye el ruido y se tiene un sistema aislado de la red. Se describe la construcción de los nuevos electrodos y se presentan los experimentos realizados con éstos. Se concluye por medio de una prueba de concepto que es posible obtener un sistema ECG no invasivo, pero que al tener una fuente dependiente de la red eléctrica existe una alta filtración de ruido de 50 Hz. La señal obtenida con el circuito y el electrodo PEDOT:PSS es satisfactoria y similar a la representación con electrodos convencionales, alimentando con un voltaje independiente de la red. Se indica los trabajos futuros respecto a esta memoria.

Gli stili APA, Harvard, Vancouver, ISO e altri

10

ACHILLI, ANDREA. "Conception, development and evaluation of polymer-based screen-printed textile electrodes for biopotential monitoring". Doctoral thesis, Università degli studi di Genova, 2019. http://hdl.handle.net/11567/977988.

Testo completo

Abstract (sommario):

Wearable technologies represent the new frontier of vital signs monitoring in different applications, from fitness to health. With the progressive miniaturization of the electronic components, enabling the implementation of portable and hand-held acquisition and recording devices, the research focus has shifted toward the development of effective and unobtrusive textile electrodes. This work deals with the study, development and characterization of organic-polymer-based electrodes for biopotentials. After an overview of the main materials and fabrication technologies presented so far in the scientific literature, the possibility to use these electrodes as an alternative to the Ag/AgCl disposable gelled electrodes usually adopted in clinical practice was tested. For this purpose, several textile electrode realization techniques were studied and optimized, in order to create electrodes with adequate features to detect two fundamental physiological signals: the electrocardiogram (ECG) and the electromyogram (EMG). The electrodes were obtained by depositing on the fabric the organic bio-compatible polymer poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT:PSS) with three deposition procedures: dipcoating, ink-jet printing and screen printing. The physical–chemical properties of the polymer solution were varied for each procedure to obtain an optimal and reproducible result. For what concerns the ECG signal, the research activity focused on screen-printed textile electrodes and their performance was first assessed by benchtop measurements and then by human trials. The first tests demonstrated that, by adding solid or liquid electrolytes the electrodes, the largest part of the characteristics required by the ANSI/AAMI EC12:2000 standard for gelled ECG electrodes can be achieved. Tests performed in different conditions showed that the skin contact impedance and the ECG morphological features are highly similar to those obtainable with disposable gelled Ag/AgCl electrodes (ρ > 0.99). A trial with ten subjects revealed also the capability of the proposed electrodes to accurately capture with clinical instruments an ECG morphology with performance comparable to off-the-shelf disposable electrodes. Furthermore, the proposed textile electrodes preserve their electrical properties and functionality even after several mild washing cycles, while they suffered physical stretching. Similar tests were performed on screen-printed textile electrodes fabricated in two different sizes to test them as EMG sensors, with and without electrolytes. After a series of controlled acquisitions performed by electro-stimulating the muscles in order to analyze the waveform morphologu of the M-wave, the statistical analysis showed a high similarity in terms of rms of the noise and electrode-skin impedance between conventional and textile electrodes with the addition of solid hydrogel and saline solution. Furthermore, the M-wave recorded on the tibialis anterior muscle during the stimulation of the peroneal nerve was comparatively analyzed between conventional and textile electrodes. The comparison provided an R2 value higher than 97% in all measurement conditions. These results opened their use in smart garments for real application scenarios and for this purpose were developed a couple of smart shirts able to detect the EGC and the EMG signal. The results indicated that this approach could be adopted in the future for the development of smart garments able to comfortably detect physiological signals.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Marquez, Ruiz Juan Carlos. "Sensor-Based Garments that Enable the Use of Bioimpedance Technology : Towards PersonalizedHealthcare Monitoring". Doctoral thesis, KTH, Medicinska sensorer, signaler och system (MSSS) (Stängd 20130701), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-107493.

Testo completo

Abstract (sommario):

Functional garments for physiological sensing purposes have been utilized in several disciplinesi.e. sports, firefighting, military and medical. In most of the cases textile electrodes (Textrodes)embedded in the garment are employed to monitor vital signs and other physiologicalmeasurements. Electrical Bioimpedance (EBI) is a non-invasive and effective technology that canbe used for detection and supervision of different health conditions. In some specific applicationssuch as body composition assessment EBIS has shown encouraging results proving good degreeof effectiveness and reliability. In a similar way Impedance Cardiography (ICG) is anothermodality of EBI primarily concerned with the determination of Stroke Volume SV, indices ofcontractility, and other aspects of hemodynamics.EBI technology in the previously mentioned modalities can benefit from a integration with agarment; however, a successful implementation of EBI technology depends on the goodperformance of textile electrodes. The main weakness of Textrodes is a deficient skin-electrodeinterface which produces a high degree of sensitivity to signal disturbances. This sensitivity canbe reduced with a suitable selection of the electrode material and an intelligent and ergonomicgarment design that ensures an effective skin-electrode contact area.This research work studies the performance of textile electrodes and garments for EBIspectroscopy for Total Body Assessment and Transthoracic Electrical Bioimpedance (TEB) forcardio monitoring. Their performance is analyzed based on impedance spectra, estimation ofparameters, influence of electrode polarization impedance Zep and quality of the signals using asreference Ag/AgCl electrodes. The study includes the analysis of some characteristics of thetextile electrodes such as conductive material, skin-electrode contact area size and fabricconstruction.The results obtained in this research work present evidence that textile garments with a dry skinelectrodeinterface like the ones used in research produce reliable EBI measurements in bothmodalities: BIS for Total Body Assessment and TEB for Impedance Cardiography. Textiletechnology, if successfully integrated, may enable the utilization of EBI in both modalities andconsequently implementing wearable applications for home and personal health monitoring.

QC 20121213

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Bashir, Tariq. "Conjugated Polymer-based Conductive Fibers for Smart Textile Applications". Doctoral thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-3649.

Testo completo

Abstract (sommario):

Electrically conductive or electro-active fibers are the key components of smart and interactive textiles, which could be used in medical, sports, energy, and military applications in the near future. The functionalization of high-performance textile yarns/fibers with conjugated polymers can produce conductive fibers with better electro-mechanical properties, which is difficult with commonly used spinning techniques. In this thesis work, textile-based conductive yarns/fibers were prepared by coating viscose and polyester (PET) yarns with the conjugated polymer PEDOT. For coating purposes, an efficient technique called chemical vapor deposition (CVD) was used, which is a solventless technique and can produce PEDOT polymer layers with high conductivity values. The polymerization of EDOT monomer vapors and coating of oxidant (FeCl3 or FepTS) enriched viscose and PET yarns took place simultaneously. The PEDOT-coated viscose and polyester yarns showed relatively high conductivity values, which could be sufficient for many electronic applications. The polymerization process and the quality of PEDOT polymer strongly depends on different reaction conditions. In this research work, the impact of most of these reaction parameters on the electrical, mechanical, and thermal properties of PEDOT-coated conductive yarns was considered separately. Under specific reaction conditions, it was found that viscose fibers were successfully coated with PEDOT polymer and showed rather high electrical conductivity (≥ 15 S/cm). However, due to the acid hydrolysis of viscose fibers in FeCl3 solutions, the mechanical properties were drastically reduced. In order to improve the mechanical properties of conductive yarns, a relatively stable and chemical-resistant substrate (PET) was coated with PEDOT polymer. Comparative studies between PEDOT-coated viscose and PET conductive yarns showed that the electrical and mechanical properties were enhanced by changing the substrate material. Later on, PEDOT-coated conductive fibers were treated with silicone elastomer solution and due to the thin silicone layers, the hydrophobic properties, flexibility, and durability of coated yarns was improved. Furthermore, a novel electrical resistance-measuring setup was developed, which can be used not only for fibers but also for fabric structures. The electrical characterization of PEDOT-coated conductive yarns showed that it can be used effectively for sensitive fibers without damaging their surface morphology. Finally, the use of conductive yarns as stretch sensors was evaluated. For this purpose, small rectangular knitted patches of conductive yarns were prepared and then the change in electrical resistance values at different extension percentages (5–50%) was investigated. The constant variations in electrical resistance values at different extension and relaxation cycles for longer periods of time revealed that the conductive yarns produced have the potential to be used as stretch sensors for monitoring of vital signs in medical and sports applications.

Thesis for the Degree of Doctor of Philosophy to be presented on March 08, 2013, 10.00 in KA-salen, Kemigården 4, Chalmers University of Technology, Gothenburg

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Nazari, Asl Sara [Verfasser], Meinhard [Akademischer Betreuer] Schilling e Peter [Akademischer Betreuer] Werning. "Development of a non-contact EEG hat using textile capacitive electrodes / Sara Nazari Asl ; Meinhard Schilling, Peter Werning". Braunschweig : Technische Universität Braunschweig, 2020. http://d-nb.info/1206334347/34.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Gismera, García Isaac. "System implementation of functional characterization of textiles electrodes for ECG measurements Software & Hardware components integration". Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20103.

Testo completo

Abstract (sommario):

The development in textile technology has led to electrodes and wearable measuringsystems. For the implementation of wearable systems is necessary to characterize properly theelectrodes and its influence in generating measurements. The validation of the performance oftextiles electrodes must be made with real ECG measurements.To obtain this ECG with textiles electrodes, a system must be implemented. This systemshould integrate an ECG amplifier, an USB DAQ system, the obtained data is received by aLabview application which stored this data in an ASCII text file. This text file is used tosubsequent study in a power analytical application, for example, Matlab.

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Bergman, Henrik Dan. "Increasing the Writing Resolution for Electro-hydrodynamic 3D-Printing : by Active Steering of e-jet". Thesis, Uppsala universitet, Mikrosystemteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-393068.

Testo completo

Abstract (sommario):

Additive manufacturing has grown considerably during the last couple of decades, whether it comes to the printing of metal structure or living cells. Additive manufacturing techniques relays on the successive addition of material to create the wanted structure. Among the diversity of these many printing techniques, electrohydrodynamic 3D-printing is of particular interest, as the technique has a promising outlook for high-resolution printing on the microscale. The technique is compatible with a myriad of thermoplastics, but its writing resolution is limited due to the inherent affect the manufacturing process has on the material. Electrostatic forces between already deposited fibres and the fibre in light affect the final position of printed fibre. This thesis evaluates the possibility to increase the writing resolution in melt electrohydrodynamic 3D printing by a closed-loop feedback system. Components were built and added to an already existing printing setup to implement in-situ measurements of the fibres position as well as active electrostatic guiding of the fibre. The setup consisted of a camera that determined the position of the fibre; the position was then used in a PID controller to calculate an appropriate potential. The potential was forwarded to a high voltage amplifier, connected to a steering electrode, mounted in the vicinity of the jet. The setup built for one-dimensional steering of the fibre improved the printing accuracy by ten times through suppressing the repulsive/attractive forces, where the process variable of the PID controller was measured. However, the precision decreased roughly four times as it was deposited on the substrate. The limitations of the system have been evaluated, and possible improvements for the two-dimensional control of the fibre are further discussed.

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Chen, Yixin. "Electron diffraction analysis of amorphous Ge2Sb2Te5". Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669987.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

17

MORAIS, ALINE V. de. "Avaliação da toxicidade e remoção da cor de um efluente têxtil tratado com feixe de elétrons". reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23903.

Testo completo

Abstract (sommario):

Submitted by Maria Eneide de Souza Araujo (mearaujo@ipen.br) on 2015-08-31T18:37:24Z No. of bitstreams: 0
Made available in DSpace on 2015-08-31T18:37:24Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Saba, Rita. "Caractérisation et conception de tags RFID-UHF dédiés aux produits textiles". Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4783.

Testo completo

Abstract (sommario):

Cette thèse s’inscrit dans le cadre d’une collaboration entre l’IM2NP et la société Tagsys, dans le cadre du projet PACID-TEXTILE. L'objectif de la thèse est de créer un tag RFID UHF packagé, très robuste et qui puisse facilement s’intégrer de manière discrète dans les produits textiles. L’idée est de concevoir deux antennes couplées et adaptées aux puces choisies pour l’application. Ces deux antennes sont conçues afin de favoriser le couplage entre elles. La première entité est packagée afin de protéger la puce de l’environnement d’utilisation. Dans une première partie, l’antenne primaire est caractérisée. Le packaging fait l’objet d’études particulières pour répondre aux contraintes de robustesses liées aux domaines du textile (blanchisserie, produit chimique). Une seconde partie du travail vise à caractériser le fil conducteur de manière à en établir une modélisation la plus fidèle possible pour pouvoir être utilisé par les outils de simulation et de conception d’antennes. Des essais de résistances du fil sont également réalisés.Enfin, une troisième partie traite de la conception d'antennes. Les tags conçus doivent avoir une portée minimale de 4m, résister à la déformation et à l'empilement. Ces tags sont soumis à différents tests pour établir leurs performances. A l’aide des moyens de caractérisations disponible au laboratoire IM2NP (plate forme de pré certification RFID), un « Benchmarking » est réalisé sur les différents tags en vue de proposer une étiquette répondant au mieux aux exigences du cahier des charges
This thesis is part of a collaboration between the company Tagsys and IM2NP, under the PACID-TEXTILE project. The aim of the thesis is to create a robust UHF RFID tag antenna that can be easily and discreetly integrated into textile products.The idea is to design two antennas electromagnetically coupled and adapted for selected chips. Both antennas are designed to facilitate the coupling between them. The first antenna is packaged in a robust material in order to protect the chip from laundry cycles. The second antenna is made up by electro-thread. The first part of the work is to characterize the packaged antenna and packaging material. The second part is to measure the conductivity of the used thread, to establish the most accurate model possible. Tests of wire resistance are also made. Toughness of each wire is also tested.The third part deals with the antenna design. The tags are designed to have a minimum range of 4m. They have to resist deformation and stacking. These tags are subjected to various tests to determine their performance. Using resources available in the laboratory IM2NP (RFID platform), a "Benchmarking " is carried on different tags to find the best that meet the requirements of the specifications

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Ezzahar, Samira. "Electro-extraction des cations en solution diluée par l'association de membranes et textiles échangeurs d'ions". Montpellier 2, 1996. http://www.theses.fr/1996MON20272.

Testo completo

Abstract (sommario):

L'epuration de solutions diluees contenant des cations metalliques a ete etudiee par la mise en uvre combinee de membranes et textiles echangeurs de cations, et du courant electrique. La faisabilite de ce procede d'electro-extraction a ete demontree. Le traitement de solutions synthetiques contenant des ions sodium, zinc et plomb, a des concentrations de quelques dizaines de ppm a ete realise sous differentes conditions. L'etude a tout d'abord ete developpee sur une cellule de laboratoire presentant une surface active de membrane de 20cm#2, puis transposee a l'echelle pre-industrielle avec un pilote presentant une surface de membrane 100 fois plus grande. Des textiles echangeurs de cations a groupement fonctionnel sulfonique ou carboxylique ont ete utilises. L'analyse des resultats obtenus, a montre que l'introduction d'un textile echangeur de cations permet d'ameliorer le procede d'electrodialyse en solution diluee: d'une part en reduisant la fuite ionique a la sortie de l'electrodialyseur, et d'autre part en augmentant la conductivite de la solution traitee. Des taux d'epuration importants, superieurs a 90%, ont ete obtenus aussi bien avec les textiles a groupement sulfonique que carboxylique, conduisant a des rejets finaux de concentration inferieure a 1ppm. La mesure de la resistance electrique des textiles a ete mise au point pour cette etude, et a permis de verifier que le textile equilibre dans une solution diluee (de concentration inferieure a 100ppm) etait plus conducteur que la solution seule. La determination des facteurs de separation relatifs a differents textiles echangeurs de cations a groupement carboxylique et sulfonique, a montre que les textiles, comme les resines, ont plus d'affinite pour les ions bivalents et les ions de numero atomique plus important, quand la solution est diluee

Gli stili APA, Harvard, Vancouver, ISO e altri

20

O'Harrow, Amber Joy Wood. "Words for a wordless world". Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/867.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Luo, Wenchen. "Excitations avec texture de spin et de pseudospin dans le graphène". Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5442.

Testo completo

Abstract (sommario):

Résumé : Nous étudions dans cette thèse plusieurs propriétés du gaz d’électrons bidimensionnel (GE2D) dans le graphène et la bicouche de graphène (BG). Nous commençons par étudier la nature des excitations à une particule du GE2D dans le graphène près des facteurs de remplissage entiers dans les niveaux de Landau N [pas égal à] 0. Nous utilisons une approche de type Hartree-Fock (HF) pour comparer l’énergie de l’excitation d’une paire électron-trou à celle d’une paire skyrmion (SK)-antiskyrmion (ASK). Dans le graphène, les excitations SK et ASK sont des excitations chargées avec une texture de spin et/ou de pseudospin de vallée qui est quantifiée topologiquement. Nos calculs montrent que les paires SK-ASK sont les excitations chargées de plus basse énergie jusqu’au niveau de Landau |N| = 3. Notre approche permet en plus de calculer le domaine de couplage Zeeman pour lequel les paires SK-ASK sont les excitations de plus basse énergie et de déterminer comment l’énergie de ces paires est modifiée par les corrections d’écrantage. Le diagramme de phase du GE2D dans la bicouche de graphène a fait l’objet d’intenses recherches théoriques et expérimentales [8, 13, 15, 16], mais jusqu’à maintenant, seuls les états uniformes ont été considérés. Nous adaptons notre approche HF à l’étude des états non uniformes pour montrer que le GE2D dans la BG à remplissage ν = −1 dans le niveau de Landau N = 0 subit une série de transitions de phase lorsqu’un champ électrique perpendiculaire à la BG est appliqué. Nous étudions tout particulièrement les phases comportant une texture de pseudospin orbital soit un cristal de skyrmions et une phase spirale. Nous calculons les modes collectifs de ces phases ainsi que leur absorption électromagnétique. Nous poursuivons ensuite avec une étude des phases cristallines autour de certains remplissages entiers dans la BG. Le GE2D dans la bicouche de graphène a principalement été étudié dans le niveau de Landau N = 0. Comme dernier problème, nous étudions le diagramme de phase lorsqu’un nombre entier de niveaux de Landau est occupé dans les niveaux supérieurs |N| > 0. Alors que l’état fondamental du GE2D dans le graphène pour ces mêmes niveaux est un ferroaimant de Hall quantique (FHQ) avec une symétrie SU(2) pour le spin (en l’absence de couplage Zeeman) et le pseudospin de vallée, le GE2D dans la BG a plutôt un comportement FHQ de type Ising avec une symétrie Z[indice inférieur 2] à champ électrique nul. Cette différence de comportement a une grande influence sur la nature des transitions de phase possibles ainsi que sur celle des excitations topologiques. // Abstract : In this thesis, we study several properties of the two-dimensional electron gas (2DEG) in graphene and bilayer graphene. We first study the nature of the single-particle excitations in graphene near integer filling factors in Landau levels (LLs) N [not equal to] 0. We use a Hartree-Fock approach to compare the energy of an electron-hole excitation pair with that of a Skyrmion-antiskyrmion pair. In graphene, Skyrmions are charged excitations with a topological quantized spin and/or valley pseudo-spin texture. We give the range of Zeeman coupling for which Skyrmion-antiskyrmion has the lowest energy up to LL N = 3. Then we discuss how screening corrections modifies these results. The phase diagram of the 2DEG in bilayer graphene had been studied previously by a number of authors [8, 13, 15, 16] but only uniform states had been considered. Extending the Hartree-Fock approach to non-uniform states, we show that at filling factor ν = −1 in LL N = 0, the 2DEG goes through a series of phase transitions as the bias from an external electric field between two layers is increased. We study a crystal phase with orbital SK textures and a spiral state with the orbital pseudospin rotating in space. We compute the collective mode of these phases and their signatures in electromagnetic absorption experiments. We finally extend the Hartree-Fock approach to study the crystal states with valley or orbital textures near integer filling factors. The research on the 2DEG in bilayer graphene has been focussed almost exclusively in LL N = 0. As our last problem, we study the phase diagram at quarter and half fillings of the quartet of states in LLs |N| > 0. While the ground state of the 2DEG in graphene in |N| > 0 is a valley and spin quantum Hall ferromagnet with SU(2) symmetry in the absence of Zeeman coupling, the ground state in bilayer graphene is an Ising quantum Hall ferromagnet with a Z[subscript 2] valley symmetry at zero bias. We note that this change has important consequences on the nature of the transport properties and the single-particle excitations at integer fillings.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Kylberg, Gustaf. "Automatic Virus Identification using TEM : Image Segmentation and Texture Analysis". Doctoral thesis, Uppsala universitet, Avdelningen för visuell information och interaktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217328.

Testo completo

Abstract (sommario):

Viruses and their morphology have been detected and studied with electron microscopy (EM) since the end of the 1930s. The technique has been vital for the discovery of new viruses and in establishing the virus taxonomy. Today, electron microscopy is an important technique in clinical diagnostics. It both serves as a routine diagnostic technique as well as an essential tool for detecting infectious agents in new and unusual disease outbreaks. The technique does not depend on virus specific targets and can therefore detect any virus present in the sample. New or reemerging viruses can be detected in EM images while being unrecognizable by molecular methods. One problem with diagnostic EM is its high dependency on experts performing the analysis. Another problematic circumstance is that the EM facilities capable of handling the most dangerous pathogens are few, and decreasing in number. This thesis addresses these shortcomings with diagnostic EM by proposing image analysis methods mimicking the actions of an expert operating the microscope. The methods cover strategies for automatic image acquisition, segmentation of possible virus particles, as well as methods for extracting characteristic properties from the particles enabling virus identification. One discriminative property of viruses is their surface morphology or texture in the EM images. Describing texture in digital images is an important part of this thesis. Viruses show up in an arbitrary orientation in the TEM images, making rotation invariant texture description important. Rotation invariance and noise robustness are evaluated for several texture descriptors in the thesis. Three new texture datasets are introduced to facilitate these evaluations. Invariant features and generalization performance in texture recognition are also addressed in a more general context. The work presented in this thesis has been part of the project Panvirshield, aiming for an automatic diagnostic system for viral pathogens using EM. The work is also part of the miniTEM project where a new desktop low-voltage electron microscope is developed with the aspiration to become an easy to use system reaching high levels of automation for clinical tissue sections, viruses and other nano-sized particles.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Hammami, Samiha. "Étude de dégradation des colorants de textile par les procédés d'oxydation avancée : application à la dépollution des rejets industriels". Phd thesis, Université de Marne la Vallée, 2008. http://tel.archives-ouvertes.fr/tel-00740155.

Testo completo

Abstract (sommario):

Cette étude porte sur l'application de différents procédés d'oxydation avancée, POA (plasma d'air humide, électro-Fenton, photo-Fenton et oxydation anodique avec BDD) pour le traitement des colorants de textile. La particularité de ces procédés tient à la génération dans le milieu d'entités très réactives et très oxydantes, les radicaux hydroxyles *OH qui sont capables d'oxyder n'importe quelle molécule organique jusqu'au stade ultime d'oxydation, c'est-à-dire la minéralisation (transformation en CO2 et H2O). Le plasma d'air humide a été appliqué pour l'oxydation d'un colorant azoïque, l'OD 61. Différents catalyseurs (Fe2+, Fe3+ et TiO2) ont été ajoutés dans leurs conditions optimisées afin d'améliorer les performances du système Glidarc. La combinaison des deux catalyseurs: Fe2+ et TiO2 a permis de décolorer 91% de l'OD 61 au bout de 3 heures et d'atteindre un taux d'abattement du COT de l'ordre de 52% après 10 heures de traitement. La méthodologie de la recherche expérimentale a été appliquée dans ce mémoire afin d'étudier l'influence de: l'intensité du courant, la concentration du colorant et le temps d'électrolyse sur la vitesse de disparition de l'OD 61 et afin de déterminer les conditions optimales de sa minéralisation. Dans les conditions optimales obtenues ([colorant] = 0,53.10-3 mol.L-1, I = 250 mA), le procédé électro-Fenton (EF) permet d'atteindre des taux de minéralisation de l'ordre de 98% dans le cas de l'OD 61 et l'AO 7 et de 88% dans le cas de l'indigo carmine. L'identification des produits intermédiaires au cours de l'électrolyse a permis de proposer un mécanisme de minéralisation de l'AO7. Les constantes cinétiques apparentes et absolues ont été déterminées. La dégradation de l'indigo a été étudiée par oxydation anodique avec BDD (OA-BDD) et par procédé photo-Fenton (PF). Cette étude a montré que l'électrolyse de l'indigo suit une cinétique de pseudo premier ordre et que le taux d'abattement du COT était de l'ordre de 97% et 63% respectivement avec OA-BDD et PF. Une étude comparative pour l'oxydation de l'AO 7 a été menée par trois procédés d'oxydation avancée: PF, OA- BDD et EF-Pt et EF-BDD. Cette étude a montré que le procédé photo-Fenton permet d'atteindre des taux d'abattement supérieurs à 90% après seulement 2 heures de traitement. Toutefois, le PF s'est révélé le plus coûteux suite à l'utilisation de la lumière artificielle UV et l'ajout des réactifs. Par ailleurs, le traitement d'un effluent réel issu de l'industrie de textile par le procédé électro-Fenton avec une anode de platine a permis la minéralisation presque totale du rejet initial (94% du COT initial ont été éliminés).

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Pinheiro, Alessandro de Sá. "Avaliação da toxicidade e genotoxicidade dos corantes azo reativos Remazol Preto B e Remazol Alaranjado 3R e da eficácia da radiação com feixe de elétrons na redução da cor e efeitos tóxicos". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-02032012-135231/.

Testo completo

Abstract (sommario):

As indústrias têxteis desempenham um importante papel na economia nacional e mundial. Entretanto, do ponto de vista ambiental, suas atividades são consideradas como potencialmente poluidoras e utilizadoras de recursos naturais. Os corantes azo reativos são os principais corantes utilizados no setor para o tingimento do algodão no Brasil e no mundo. Devido à sua baixa fixação à fibra e a variações no processo de produção, cerca de 30 % da concentração inicial utilizada nos banhos de tingimento são perdidos e vão compor o efluente final. Esses compostos apresentam uma baixa biodegradabilidade e elevada solubilidade em água e, por isso, não são completamente removidos pelos processos biológicos convencionais. Os corantes quando descartados sem tratamento adequado no corpo dágua receptor podem causar modificações estéticas, alterar a fotossíntese e a solubilidade dos gases, além de serem tóxicos e genotóxicos para a biota. Os principais objetivos do trabalho foram avaliar a toxicidade e genotoxicidade de dois diferentes corantes azo reativos (Remazol Preto B RPB e Remazol Alaranjado 3R R3AR) e a eficiência de redução da cor e toxicidade após o uso da radiação com feixe de elétrons. Também foi analisada a toxicidade dos corantes em diferentes formas químicas, que podem ser encontradas nos efluentes. Os ensaios de toxicidade aguda realizados com Vibrio fischeri, Daphnia similis e Biomphalaria glabrata evidenciaram diferentes padrões de resposta para os corantes. Os dois corantes em suas formas químicas foram levemente tóxicos para Vibrio fischeri, com exceção da forma vinilsulfona do corante RPB que foi tóxico (CE(I)5015min = 6,23 mg L-1). Nos ensaios com Daphnia similis, o corante RPB foi levemente tóxico na sua forma original, sulfatoetilsulfona (CE(I)5048h = 91,25 mg L-1) e não apresentou toxicidade nas demais formas químicas. Entretanto, o corante RA3R foi tóxico para o dafnídeo, sendo muito tóxico na forma vinilsulfona (CE(I)5048h = 0,54 mg L-1). Não foi observada toxicidade nos ensaios com o organismo Biomphalaria glabrata. A toxicidade crônica foi avaliada com o organismo Ceriodaphnia dubia e o corante RPB apresentou valores de CENO e CEO iguais a 12,5 e 25 mg L-1, respectivamente, para a forma sulfatoetilsulfona. Após a hidrólise do corante (vinilsulfona e hidroxietilsulfona) foi observado um aumento os valores obtidos de CENO e CEO. Não foi verificado efeito crônico para o corante R3AR e suas formas químicas. O teste do cometa adaptado para o caramujo Biomphalaria glabrata foi utilizado para avaliar a genotoxicidade dos corantes. O corante RPB apresentou genotoxicidade nas concentrações mais elevadas (1 e 2 g L-1), com valores de dano quantitativo de 117 e 112 e o R3AR não foi genotóxico. O uso da radiação com feixes de elétrons demonstrou eficácia na remoção da cor dos corantes. Com a dose de 10 kGy foi possível uma redução de 97,64 % para RPB e de 96,8 % para R3AR. Após irradiação do corante RPB com a dose de 10 kGy foi evidenciada uma redução de 59,52 % da toxicidade aguda avaliada com Vibrio fischeri. Nas demais doses não houve redução significativa, assim como na avaliação com Daphnia similis, onde os valores de CE(I)5048h obtidos foram menores que o corante não irradiado. O corante R3AR apresentou diminuição da toxicidade mais acentuada após a radiação quando comparado com o RPB, com reduções de 82,95 % (V. fischeri) e 71,26 % (D. similis) com 10 kGy.
The textile industries play an important role in national and global economy. But, their activities are considered potentially polluting. The use of large volumes of water and the production of colored wastewater with high organic matter are among the main issues raised, especially during the stage of dyeing and washing of the textile process. The reactive azo dyes are the main colors used in the industry for dyeing of cotton in Brazil and worldwide. Because of its low setting and variations in the fiber production process, about 30% of the initial concentration used in the dyeing baths are lost and will compose the final effluent. These compounds have a low biodegradability, are highly soluble in water and therefore are not completely removed by conventional biological processes. In addition, other processes do not promote degradation but the tranference to solid environment. The dyes discarded without treatment in the water body can cause aesthetic modifications, alter photosynthesis and gas solubility, as well as being toxic and genotoxic. The main objectives of this study were to evaluate the toxicity and genotoxicity of two reactive azo dyes (Remazol Black B - RPB and Remazol Orange 3R R3AR) and the percentage of color and toxicity reduction after the use of electron beam radiation. The acute toxicity assays performed with Vibrio fischeri, Daphnia similis and Biomphalaria glabrata showed different response patterns for dyes. The different chemical forms of dyes were slightly toxic to Vibrio fischeri and only the RPB dye (vinylsulphone) was toxic (EC5015min = 6,23 mg L-1). In tests with Daphnia similis, the dye RPB was slightly toxic in its patern form, sulphatoethylsulphone, (CE5048h = 91,25 mg L-1) and showed no toxicity in other chemical forms. However, the RA3R dye was toxic to the dafnids and the vinylsulphone form very toxic (EC5048h = 0,54 mg L-1). No toxicity was observed in Biomphalaria glabrata assays. Chronic toxicity was assessed with the organism Ceriodaphnia dubia and the NOEC and OEC values of RPB dye (sulphatoethylsulphone) were 12.5 and 25 mg L-1, respectively. After hydrolysis of the dye (vinylsulphone and hydroxyethylsulphone) was shown to increase the values obtained from the NOEC ans OEC. There was no chronic effect for the R3AR dye and its chemical forms to C. dubia. The comet assay adapted to hemocytes of Biomphalaria glabrata was used to assess the genotoxicity of the dyes. The RPB dye was genotoxic at highest concentrations (1 and 2 g L-1), with quantitative values of DNA damage equal to 117 and 112 and the R3AR dye was not genotoxic. The use of radiation with electron beams have proven effective in removing the color dyes. With a dose of 10 kGy a reduction of 97.64% and 96.8% for R3AR and RPB, respectively, was achievied. Possibly, the color removal was mainly due to the interaction of reactive species such as hydroxyl radicals generated in the radiolysis of water after the radiation beam of electrons. After radiation of the RPB dye a dose of 10 kGy reduced 59.52 % of the acute toxicity measured with Vibrio fischeri. For the other doses there was no significant reduction, as well as with Daphnia similis, where the values of EC5048h obtained were smaller than the non-irradiated dye. The R3AR dye showed better decreased toxicity after radiation when compared with the RPB, with reductions of 82.95% (V. fischeri) and 71.26% (D. similis) with 10 kGy.

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Hamdany, Nowfal al [Verfasser]. "Texture and stress characterization of a Copper Tube by neutron, synchrotron and electron diffraction / Nowfal Al-Hamdany". Clausthal-Zellerfeld : Universitätsbibliothek Clausthal, 2015. http://d-nb.info/1078228248/34.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Woerner, Rachel Anna. "Development of cryopreparation methods and improved staining techniques for transmission electron microscopy of wool". Thesis, Queensland University of Technology, 2002.

Cerca il testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Ong, Hannah Chien Leing. "Virus recognition in electron microscope images using higher order spectral features". Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16186/1/Hannah_Chien_Leing_Ong_Thesis.pdf.

Testo completo

Abstract (sommario):

Virus recognition by visual examination of electron microscope (EM) images is time consuming and requires highly trained and experienced medical specialists. For these reasons, it is not suitable for screening large numbers of specimens. The objective of this research was to develop a reliable and robust pattern recognition system that could be trained to detect and classify different types of viruses from two-dimensional images obtained from an EM. This research evaluated the use of radial spectra of higher order spectral invariants to capture variations in textures and differences in symmetries of different types of viruses in EM images. The technique exploits invariant properties of the higher order spectral features, statistical techniques of feature averaging, and soft decision fusion in a unique manner applicable to the problem when a large number of particles were available for recognition, but were not easily registered on an individual basis due to the low signal to noise ratio. Experimental evaluations were carried out using EM images of viruses, and a high statistical reliability with low misclassification rates was obtained, showing that higher order spectral features are effective in classifying viruses from digitized electron micrographs. With the use of digital imaging in electron microscopes, this method can be fully automated.

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Ong, Hannah Chien Leing. "Virus recognition in electron microscope images using higher order spectral features". Queensland University of Technology, 2006. http://eprints.qut.edu.au/16186/.

Testo completo

Abstract (sommario):

Virus recognition by visual examination of electron microscope (EM) images is time consuming and requires highly trained and experienced medical specialists. For these reasons, it is not suitable for screening large numbers of specimens. The objective of this research was to develop a reliable and robust pattern recognition system that could be trained to detect and classify different types of viruses from two-dimensional images obtained from an EM. This research evaluated the use of radial spectra of higher order spectral invariants to capture variations in textures and differences in symmetries of different types of viruses in EM images. The technique exploits invariant properties of the higher order spectral features, statistical techniques of feature averaging, and soft decision fusion in a unique manner applicable to the problem when a large number of particles were available for recognition, but were not easily registered on an individual basis due to the low signal to noise ratio. Experimental evaluations were carried out using EM images of viruses, and a high statistical reliability with low misclassification rates was obtained, showing that higher order spectral features are effective in classifying viruses from digitized electron micrographs. With the use of digital imaging in electron microscopes, this method can be fully automated.

Gli stili APA, Harvard, Vancouver, ISO e altri

29

LOW, MARJORIE. "Estudo do desenvolvimento da textura durante a recristalização primária de aços ferríticos por difração de raios X e difração de elétrons retroespalhados". reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11449.

Testo completo

Abstract (sommario):

Made available in DSpace on 2014-10-09T12:52:01Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T13:57:53Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Lacson, Carmina, e Alice Johansson. "Undersökning av lämpligt tryck att tillämpa i medicinska sensoriska plagg : Vilket tryck mot huden krävs för tillförlitliga signaler från textila sensorer". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-26576.

Testo completo

Abstract (sommario):

För att kunna underlätta för sjukvården, både med avseende att belastning och för att underlätta för patienter med allergier mot t.ex. limmet som används för att fästa elektroder mot kroppen, arbetas det med att ta fram sensoriska plagg. Ett sensoriskt plagg kan användas för att kontrollera olika mätvärden i vardagen så som hjärtsignaler eller liknande och ska vara lätt för patienten att använda själv hemma. Eller som ett alternativ för någon som är allergisk mot det lim som vanligtvis används för att fästa sensorer mot kroppen. För att sensorerna i plagget ska kunna ge tydliga och användbara mätningar behöver de sitta stilla med ett jämt tryck på sensorerna mot kroppen. För att användaren av det sensoriska plagget ska vilja använda plagget och finna det bekvämt kan inte trycket mot kroppen vara för högt. Därför är det viktigt att ta reda på vilket tryck som uppfattas som bekvämt och vara funktionellt, men också är tillräckligt högt för att få en tydlig och användbar mätning. I denna rapport undersöks därför vilket tryck som uppfattas som gångbart ur användarsynpunkt. Undersökningen genomfördes med hjälp av elva deltagare som testat olika tryck och hur dessa tryck förändras under rörelse. Detta för att hitta vilket tryck deltagarna uppfattade som användbart och tillräckligt bekvämt för att använda i vardagen. Denna undersökning visa stora skillnader på vilket tryck som uppfattas som bekvämt och hur mycket trycket förändras under rörelse. Samt att statisk position inte påverkar signalerna från hjärtat anmärkningsvärt vid de undersökta trycken.
To relieve and ease a small part of the healthcare from work overload and help patients with allergies to glue used to attach the standard sensors, a sensor-equipped wearable garment could be used. The wearable garment could be used to monitor a patient´s values during the day and should be easy for the patient to use themselves at home and comfortable to use every day, or for a patient who is allergic to the glue usually used to attach the sensors. To make the sensors on the sensor-equipped garment work the sensors must sit with pressure against the body to get readable and useful measurement. The pressure from the sensors around the body can not be too tight if it gets too uncomfortable. Therefore it is important to find what pressure that is comfortable enough for the patient to use everyday but still get good enough readings from the measuring devise to be used to monitor the patient´s values. This study looks into what pressure that the participants perceive as comfortable to use on an everyday basis. In this study the pressure is measured on eleven different participants, the pressure was measured at different times and when the participants performed different movements too document the changes in the pressure at movement to find what pressure the participants perceive as comfortable enough for everyday use. This study shows that the pressure perceived as comfortable varies between participants and that the pressure change during movement. It also shows that static position do not affect the quality of the signals from the heart at the used pressures.

Gli stili APA, Harvard, Vancouver, ISO e altri

31

SERNA, MARILENE M. "Estudo comparativo da analise de macrotextura pelas tecnicas de difracao de raios X e difracao de eletrons retroespalhados". reponame:Repositório Institucional do IPEN, 2002. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11013.

Testo completo

Abstract (sommario):

Made available in DSpace on 2014-10-09T12:46:56Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:09:47Z (GMT). No. of bitstreams: 1 09060.pdf: 8685574 bytes, checksum: 4cca556c554e4dce4f2f896a6cd6f9fd (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Vafaee, Maedeh. "Conception, développement et caractérisation des fibres spécifiques activées (composite nanoweb) pour le traitement des rejets de l'industrie textile". Thesis, Mulhouse, 2019. http://www.theses.fr/2019MULH3062.

Testo completo

Abstract (sommario):

Dans cette recherche, dans un premier temps, un nouveau catalyseur a été synthétisé par une nouvelle méthode de combustion et il a été également caractérisé et mis en oeuvre dans un réacteur photo catalytique afin de dégrader les composés organiques. Puis, ces photo-catalyseurs ont été immobilisés sur la surface de non-tissés de nano fibres polyamide obtenues par le procédé d'électro-filage (electro-spinning) en utilisant une machine semi-industrielle. Ensuite, les comportements mécaniques de non tissés de nano-fibre de polyamide (PA) ont été étudiés à court et à long terme par test de traction et de fluage. Ceci a permis d'une part d'évaluer finement les propriétés des non tissés et d'autre part de modéliser leur comportement au moyen de modèles analogiques. Le modèle de Kelvin-Voigt généralisé a montré sa robustesse. Ces non tissés de nanofibres ont été installés sur 1a paroi du réacteur afin d'avoir un réacteur en inox à lit fixe et d'éviter des inconvénients d'un système hétérogène. Les résultats d'analyse des solutions, nous ont montré une dégradation favorable des composés organiques et les produits intermédiaires dans un système de circulation fermée. La mise sous pression du réacteur a confirmé, comme montré dans les essais mécaniques, que les propriétés mécaniques des fibres dopées étaient suffisantes pour supporter les contraintes mécaniques liées au flux du liquide
In this research, at first, a new catalyst was synthesized by a new combustion method and it was also characterized and applied in a photo-catalytic reactor to degrade the organic compounds. Then, these photocatalysts were immobilized on the surface of nonwovens of polyamide nano fibers obtained by the electro-spinning process using a semi-industrial machine. Then, the mechanical behaviors of polyamide (PA) nano-fiber nonwovens were studied in the short and long term by tensile and creep test. This allowed on the one hand to evaluate finely the properties of nonwovens and on the other hand to model their behavior on average of analog models. The generalized Kelvin-Voigt model has shown its robustness. They were installed on the reactor wall in order to have a stainless steel fixed bed reactor and to avoid the disadvantages of a heterogencous system. The solution analysis results showed us a favorable degradation of organic compounds and intermediate products in a closed circulation system. Pressurizing the reactor confirmed, as shown in the mechanical tests, that the mechanical properties of the doped fibers were sufficient to withstand the mechanical stresses associated with the flow of the Jiquid

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Bastos, da Silva Fanta Alice. "Characterization of the microstructure, grain boundaries and texture of nanostructured electrodeposited CoNi by use of electron backscatter diffraction (EBSD)". Göttingen Cuvillier, 2007. http://d-nb.info/991032845/04.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Bastos, da Silva Fanta Alice. "Characterization of the microstructure, grain boundaries and texture of nanostructured electrodeposited CoNi by use of Electron Backscatter Diffraction (EBSD) /". Göttingen : Cuvillier, 2008. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=017078787&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Annan, Kofi Ahomkah. "Effect of hot working characteristics on the texture development in AISI 430 and 433 ferritic stainless steel". Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/25436.

Testo completo

Abstract (sommario):

The last seven hot rolling passes of the ferritic stainless steels (FSS) AISI 430 and AISI 433 (the latter an Al-added variant of 430) were simulated on Gleeble-1500D® and Gleeble-3800TM® thermo-mechanical simulators to investigate the effect of temperature, strain rate and inter-pass time on the development of texture in these steel grades and its subsequent influence on ridging. The compression tests were carried out over a wide range of strain rates (0.1 s-1 to 5 s-1, 25 s-1 and 50 s-1) and temperatures (1100 to 820 oC) with different inter-pass times (2 s, 10 s, 20 s and 30 s). The transition temperature from dynamic recrystallization (which may introduce a texture change) to dynamic recovery (in which no texture changes are expected) was determined by examining the relationship between the mean flow stress and the deformation temperature in multi-pass tests. Both macrotexture (XRD) and microtexture (EBSD) analyses were employed to characterise and study the texture present in these steels. It was found that the texture in the central layer of the compressed sample is a strong recrystallization-type. The through-thickness textural and microstructural banding was found to be responsible for ridging in these grades of stainless steels. Dynamic recrystallization which promotes the formation of the desired ã-fibre texture leading to high ductility, formability and eventually reduction or elimination of ridging, was found to occur in both AISI 430 and AISI 433 at high temperatures, low strain rates and longer inter-pass times with multi-pass testing. Generally AISI 433 has a stronger gamma texture developed than the AISI 430 when hot rolled under similar conditions, which leads to improved ductility and less ridging in AISI 433 than AISI 430.
Dissertation (MSc)--University of Pretoria, 2012.
Materials Science and Metallurgical Engineering
unrestricted

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Shim, Sohie. "Analytical techniques for differentiating huacaya and suri alpaca fibers". Connect to this title online, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1064202091.

Testo completo

Abstract (sommario):

Thesis (Ph. D.)--Ohio State University, 2003.
Document formatted into pages; contains x, 108 p. Includes bibliographical references (p. 102-108). Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2006 Sep. 22.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Bouafia-Chergui, S. "Dégradation des colorants textiles par procédés d'oxydation avancée basée sur la réaction de Fenton. Application à la dépollution des rejets industriels". Phd thesis, Université de Marne la Vallée, 2010. http://tel.archives-ouvertes.fr/tel-00740134.

Testo completo

Abstract (sommario):

Les procédés dits d'oxydation avancés (POA) permettent la dégradation totale (minéralisation) en milieu aqueux des polluants organiques persistants et/ou toxiques pour l'homme et pour l'environnement. Cette étude porte sur l'application de deux POA principaux : électro-Fenton et photo-Fenton, au traitement des eaux polluées par des colorants de textile. La particularité de ces procédés tient à la génération dans le milieu d'entités oxydantes très réactives, les radicaux hydroxyles (..OH) qui sont capables d'oxyder n'importe quelle polluant organique ou organométallique jusqu'au stade ultime d'oxydation, c'est-à-dire la minéralisation (transformation en CO2 et H2O). Dans le cas des colorants étudiés (BB41, BR46 et BY28), il a été montré que le taux de minéralisation par le procédé électro-Fenton dépend des paramètres expérimentaux tels que la concentration du catalyseur, l'intensité du courant appliqué, le pH du milieu, etc.. Cette étude a montré que l'électrolyse du colorant suit une cinétique de pseudo premier ordre. Dans les conditions expérimentales optimales (I = 225 mA et [Fe3+]0 = 0,1 mM), les taux de minéralisation obtenus pour des solutions aqueuses des trois colorants étudiés étaient de 93, 82 et 73% pour le BB41, BR46 et BY28 respectivement après 6 h de traitement. Le taux de minéralisation par le procédé photo-Fenton (UV/Fe3+/H2O2) est fonction des doses des réactifs utilisés et des rapports R = [H2O2]/[Fe3+] et R' = [Fe3+]/[substrat]. Ainsi, les taux de minéralisation obtenus sont de l'ordre de 93% pour le BB41, 85% pour le BR46 et de 95% pour le BY28 pour une durée de traitement de 5 heures avec des rapports R = 10 et R' = 40. L'étude de la dégradation du colorant BB41 sur une unité pilote utilisant le rayonnement solaire a montré que le procédé hélio-photo-Fenton est très efficace. Ce procédé s'inscrit dans une perspective de développement durable et son fonctionnement est basé sur une énergie renouvelable. Une comparaison des performances de minéralisation d'un mélange de colorants par les deux procédés étudiés par l'estimation de l'énergie électrique consommée a montré que les procédés photo-Fenton et électro-Fenton permettent d'atteindre des taux de minéralisation très importants et que le procédé électro-Fenton semble être favorisé avec non utilisation de réactifs chimiques et une faible consommation d'énergie électrique.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

FERREIRA, PATRICIA C. "Remoção de corantes de efluente textil por zeólita de cinzas de carvão modificada por surfactante e avaliação dos efeitos tóxicos". reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/25302.

Testo completo

Abstract (sommario):

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-12-10T17:52:55Z No. of bitstreams: 0
Made available in DSpace on 2015-12-10T17:52:55Z (GMT). No. of bitstreams: 0
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Waters, Brent R. "Mechanical Properties of Inconel 718 Processed Using Electron Beam Free Form Fabrication (EBF³)". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/6717.

Testo completo

Abstract (sommario):

Electron beam freeform fabrication (EBF3) is a rapid metal deposition process that works efficiently with the wieldable alloy Inconel 718 (IN 718). EBF3 is a developing additive manufacturing (AM) process that can manufacture IN 718 parts directly from computer aided design (CAD) data. EBF3 can produce parts significantly faster and more energy efficient than competing IN 718 AM technologies. The EBF3 process utilizes metal wire feedstock which is induced into a molten pool using a focused electron beam in a vacuum environment. This allows parts to be built layer by layer, creating intricate shapes that can be produced cheaper and faster than traditionally manufactured IN 718 parts. Furthermore, it allows traditionally manufactured parts to be modified as additional form is added to them using EBF3. Multiple industries rely on IN 718 parts and can utilize this technology including aerospace engineering, oil refinery, nuclear power generation, and food processing.A main drawback of EBF3 is the lack of knowledge of the effect different EBF3 build techniques will have on the properties of the deposited materials. Most of the reliable data on the mechanical properties relate to a linear build-up strategy and focus on the mechanical properties in the deposition direction (DD). There is no data related to other build-up techniques such as rotation build-up or transitional builds from forged material to EBF3 material. Reliable data on the behavior and microstructure of EBF3 material in a direction other than the DD is also difficult to find. Previous studies showed build-up height influenced mechanical properties but its role is not fully understood yet. This paper presents the mechanical properties and microstructure of an IN 718 plate built using a EBF3 rotational build-up strategy through utilizing a forged plug in the center. The tensile properties of samples at the transition from forged to EBF3 material showed higher ductility and reduced strength than pure EBF3 material. This is likely due the influence of the forge material in one half of the specimen. Samples taken at approximately 15 degree increments from 0 to 90 degrees rotation to the DD in the additive portion of the plate were subjected to tensile testing. Along the build height, or the transverse direction (TD), the lowest strength was demonstrated and the TD aligned strongly to a <001> texture. Samples 45 degrees to the DD showed the greatest strength due to their preference for aligning to a <111> texture. Samples low on the build height demonstrated a higher strength than those on the top and displayed grain structures along the TD which were long, linear, and narrow across multiple deposition layers.

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Marashi, Seyed Pirooz Hoveida. "Transmission electron microscopy study of nanostructured Nd-Fe-B hard magnetic materials". Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366102.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Leroy, Joël. "Caractérisation et qualification de cokes industriels : relations entre texture poreuse, microtexture, sites actifs et carboxyréactivité". Vandoeuvre-les-Nancy, INPL, 1991. http://docnum.univ-lorraine.fr/public/INPL_T_1991_LEROY_J.pdf.

Testo completo

Abstract (sommario):

Ce travail a pour but de relier carboxyréactivité et caractéristiques de 5 cokes. On étudie en fonction de la gazéification: texture poreuse, microtexture et sites actifs. La confrontation des résultats conduit à des conclusions concordantes et complémentaires. Plus un coke est microporeux, plus il est réactif. Cependant la mésoporosité ouvre l'accès aux réactifs. Une forte réactivité résulte de la présence simultanée de micro- et de mésoporosité ce qui est en accord avec le fait que les cokes les plus réactifs présentent une grande diversité dans les dimensions des domaines d'O. M. Les variations de la réactivité au cours de la gazéification, dont le régime est essentiellement diffusionnel dans le domaine exploré, sont liées à l'évolution de la porosité. Il est possible de calculer les gazéifications interne et externe. La microtexture renseigne sur l'existence d'une microporosité et de sites actifs, pour la plupart inaccessibles, donc sur la réactivité potentielle. Cependant la réactivité effective dépend de la surface accessible. Les sites actifs ont été étudiés par T. D. P des oxydes de surface. L'Aire de la Surface Active (A. S. A. ) ainsi mesurée sur les cokes bruts est en très bonne corrélation avec leur carboxyréactivité à 900°C ce qui s'interprète comme suit: les oxydes thermodésorbés des cokes bruts proviennent des complexes formes au cours de l'extinction humide sur les sites accessibles, la carboxyréactivité considérée est liée aux sites accessibles au CO2 à 900°C. Ces deux types de sites ne sont vraisemblablement pas très différents. On teste donc ainsi directement sur un coke brut une grandeur caractéristique de sa carboxyréactivité à 900°C
This work was intended to connect the carboxyreactivity of 5 cokes samples with their physico-chemical properties. Porous textures, microtextures and active sites were studied with respect to the gasification extent. Analysis of the results leads to concordant and complementary conclusions. The more microporous a sample the more reactive. However mesoporosity gives access to the reactants. The simultaneous presence of micro-and of mesoporosity results in a high reactivity. This agrees with the fact that the most reactive cokes exhibit a wide distribution of the sizes of M. O. Dormains. Variations of reactivity during gasification, whose mode is mainly diffusional, are linked to the alterations of the porosity. It was possible to compute the extent of internal and of external gasification. Microtexture gives informations about the presence of a microporosity and of active sites, mainly non accessible, therefore about “potential reactivity”. However “effective reactivity” depends on surface accessibility. Active sites were studied by TPD of surface oxides. The Active Surface Area (A. S. A. ) determined on raw cokes correlates well with their carboxyreactivity at 900° C. This is interpreted as follows : desorbed oxides from raw cokes originate in complexes formed on accessible sites during quenching, the carboxyreactivity studied at 900°C is related to accessible sites ; these two types of sites are likely to be not too different. So it seems possible to determine on a raw coke a feature relevant of its carboxyreactivity at 900°C

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Morais, Aline Viana de. "Avaliação da toxicidade e remoção da cor de um efluente têxtil submetido ao tratamento com feixe de elétrons". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-18052015-144706/.

Testo completo

Abstract (sommario):

A indústria têxtil está entre uma das principais atividades do Brasil, sendo relevante em número de empregos, quantidade e diversidade de produtos e principalmente pelo volume de água utilizado nos processos industriais e na geração de efluentes. Esses efluentes são misturas complexas que se caracterizam pela presença de corantes, surfactantes, metais, sequestrantes, sais entre outras substâncias químicas com potencial tóxico a biota aquática. Considerando a escassez de tratamentos adequados a esses efluentes, novas tecnologias são essenciais em que se destacam os processos de oxidação avançada como a radiação ionizante por feixe de elétrons. Esse estudo contempla o preparo de um efluente têxtil padrão em laboratório de química têxtil e seu tratamento por feixe de elétrons proveniente de acelerador de elétrons a fim de diminuir a toxicidade e coloração intensa decorrente do corante C.I. Blue 222. O tratamento promoveu diminuição de toxicidade aguda aos organismos expostos, com eficiência de 34,55% para o micro-crustáceo Daphnia similis e de 47,83% para o rotífero Brachionus plicatilis na dose de 2,5 kGy. No ensaio com a bactéria Vibrio fischeri foi obtido o melhor resultado após o tratamento com dose de 5 kGy e eficiência de 57,29%. A redução da cor foi superior a 90% a partir da dose de 2,5 kGy. Neste trabalho também foram realizados ensaios preliminares de toxicidade aguda quanto à sensibilidade dos organismos D. similis e V. fischeri à exposição de alguns dos produtos utilizados no processo de alvejamento e tingimento, além de duas simulações de reuso de água em novos processos têxteis a partir do efluente tratado com feixe de elétrons.
The textile industry is among the main activities Brazil, being relevant in number of jobs, quantity and diversity of products and mainly by the volume of water used in industrial processes and effluent generation. These effluents are complex mixtures which are characterized by the presence of dyes, surfactants, metal sequestering agents, salts and other potentially toxic chemicals for the aquatic biota. Considering the lack of adequate waste management to these treatments, new technologies are essential in highlighting the advanced oxidation processes such as ionizing radiation electron beam. This study includes the preparation of a standard textile effluent chemical laboratory and its treatment by electron beam from electron accelerator in order to reduce the toxicity and intense staining resulting from CI. Blue 222 dye. The treatment caused a reduction in toxicity to exposed organisms with 34.55% efficiency for the Daphnia similis micro-crustacean and 47.83% for Brachionus plicatilis rotifer at a dose of 2.5 kGy. The Vibrio fischeri bacteria obtained better results after treatment with a dose of 5 kGy showing 57.29% efficiency. Color reduction was greater than 90% at a dose of 2.5 kGy. This experiment has also carried out some preliminary tests on the sensitivity of the D. similis and V. fischeri organisms to exposure of some of the products used in this bleaching and dyeing and two water reuse simulations in new textile processing after the treating the effluent with electron beam.

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Jakubíček, Marek. "Nositelná anténa pro komunikaci v blízkosti lidského těla". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221243.

Testo completo

Abstract (sommario):

This thesis describes the possibilities of wearable antennas and the basic properties description. Numeric model for ISM 2,4 GHz band is created by CST Microwave Studio®. The thesis also deals with the human body proximity effect by two models of human tissue. The effect of flexibility to antenna parameters is evaluated. Several samples of the antenna has been created and measured. Obtained results has been compared with numeric model and with the literature.

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Bernier, Jeremy Scott. "Evolution and Characterization of Partially Stabilized Zirconia (7wt% Y2O3) Thermal Barrier Coatings Deposited by Electron Beam Physical Vapor Deposition". Digital WPI, 2002. https://digitalcommons.wpi.edu/etd-theses/826.

Testo completo

Abstract (sommario):

Thermal barrier coatings (TBCs) of ZrO2-7wt% Y2O3 were deposited by electron beam physical vapor deposition (EB-PVD) onto stationary flat plates and cylindrical surfaces in a multiple ingot coater. Crystallographic texture, microstructure, and deposition rate were investigated in this thesis. The crystallographic texture of EB-PVD TBCs deposited on stationary flat surfaces has been experimentally determined by comparing pole figure analysis data with actual column growth angle data. It was found that the TBC coating deposited directly above an ingot exhibits <220> single crystal type crystallographic texture. Coatings deposited between and off the centerline of the ingots the exhibited a <311>-type single crystal texture. For coatings deposited in the far corners of the coating chamber either a <111> fiber texture or a <311> single crystal type texture existed. The crystallographic texture of EB-PVD TBCs deposited on cylindrical surfaces was characterized using x-ray diffraction (XRD) at different angular positions on the cylinder substrate. XRD results revealed that crystallographic texture changes with angular position. Changes in crystallographic texture are attributed to the growth direction of the columns and substrate temperature. Growth direction is controlled by the direction of the incoming vapor flux (i.e. vapor incidence angle), in which competition occurs between crystallites growing at different rates. The fastest growing orientation takes over and dominates the texture. Substrate temperature variations throughout the coating chamber resulted in different growth rates and morphology. Morphology differences existed between cylindrical and flat plate surfaces. Flat cross sectional surfaces of the coatings exhibited a dense columnar structure in which the columns grew towards the closest vapor source. Surface features were found to be larger for coatings deposited directly above an ingot than coatings deposited away from the ingots. Morphological differences result from substrate temperature changes within the coating chamber, which influences growth kinetics of the coating. Cylindrical surfaces revealed a columnar structure in which columns grew towards the closest vapor. Porosity of the coating was found to increase when the angular position changed from the bottom of the cylinder. Change in angular position also caused the column diameter to decreases. Morphology changes are attributed to self-shadow effects caused by the surface curvature of the cylinder and vapor incidence angle changes. Overall, the microstructure and crystallographic texture of EB-PVD coatings was found to depend on the position in the coating chamber which was found to influence substrate temperature, growth directions, and shadowing effects. The coating thickness profiles for EB-PVD TBCs deposited on stationary cylinders have been experimentally measured and theoretically modeled using Knudsen's cosine law of emissions. A comparison of the experimental results with the model reveals that the model must to be modified to account for the sticking coefficient as well as a ricochet factor. These results are also discussed in terms of the effects of substrate temperature on the sticking coefficient, the ricochet factor, and coating density.

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Chergui, Souâd. "Dégradation des colorants textiles par procédés d'oxydation avancée basée sur la réaction de Fenton : application à la dépollution des rejets industriels". Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00582374.

Testo completo

Abstract (sommario):

Les procédés dits d'oxydation avancés (POA) permettent la dégradation totale (minéralisation) en milieu aqueux des polluants organiques persistants et/ou toxiques pour l'homme et pour l'environnement. Cette étude porte sur l'application de deux POA principaux : électro-Fenton et photo-Fenton, au traitement des eaux polluées par des colorants de textile. La particularité de ces procédés tient à la génération dans le milieu d'entités oxydantes très réactives, les radicaux hydroxyles (●OH) qui sont capables d'oxyder n'importe quelle polluant organique ou organométallique jusqu'au stade ultime d'oxydation, c'est-à-dire la minéralisation (transformation en CO₂ et H₂O). Dans le cas des colorants étudiés (BB41, BR46 et BY28), il a été montré que le taux de minéralisation par le procédé électro-Fenton dépend des paramètres expérimentaux tels que la concentration du catalyseur, l'intensité du courant appliqué, le pH du milieu, etc.. Cette étude a montré que l'électrolyse du colorant suit une cinétique de pseudo premier ordre. Dans les conditions expérimentales optimales (I = 225 mA et [Fe³⁺]₀ = 0,1 mM), les taux de minéralisation obtenus pour des solutions aqueuses des trois colorants étudiés étaient de 93, 82 et 73% pour le BB41, BR46 et BY28 respectivement après 6 h de traitement. Le taux de minéralisation par le procédé photo-Fenton (UV/Fe³⁺/H₂O₂) est fonction des doses des réactifs utilisés et des rapports R = [H₂O₂]/[Fe³⁺] et R' = [Fe³⁺]/[substrat]. Ainsi, les taux de minéralisation obtenus sont de l'ordre de 93% pour le BB41, 85% pour le BR46 et de 95% pour le BY28 pour une durée de traitement de 5 heures avec des rapports R = 10 et R' = 40. L'étude de la dégradation du colorant BB41 sur une unité pilote utilisant le rayonnement solaire a montré que le procédé hélio-photo-Fenton est très efficace. Ce procédé s'inscrit dans une perspective de développement durable et son fonctionnement est basé sur une énergie renouvelable. Une comparaison des performances de minéralisation d'un mélange de colorants par les deux procédés étudiés par l'estimation de l'énergie électrique consommée a montré que les procédés photo-Fenton et électro-Fenton permettent d'atteindre des taux de minéralisation très importants et que le procédé électro-Fenton semble être favorisé avec non utilisation de réactifs chimiques et une faible consommation d'énergie électrique

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Medy, Jean Rony. "Évaluation des effets de taille et d'architecture sur les propriétés mécaniques et électriques de fils composites métalliques cuivre/niobium fabriqués par déformation plastique sévère". Thesis, Poitiers, 2016. http://www.theses.fr/2016POIT2312/document.

Testo completo

Abstract (sommario):

Les fils composites Cu/Nb étudiés ici sont d'excellents candidats pour les bobines non destructives générant des champs magnétiques pulsés intenses (B ≥ 100T). Ils sont fabriqués par Accumulative Drawing and Bundling (ADB) et sont constitué de renforts continus de Nb dans une matrice multi-échelles de Cu. Ces travaux rentrent dans le cadre du projet METAFORES (ANR-12-BS09-0002), visant l’évaluation des effets de taille et d’architecture sur les propriétés des conducteurs Cu/Nb. L’objectif principal consiste donc à caractériser leur microstructure et leurs propriétés à chaque étape de la fabrication par différentes techniques de caractérisation. Des essais mécaniques et électriques montrent une augmentation de la limite d’élasticité avec l’affinement de la microstructure tout en conservant une conductivité électrique adéquate. Les études de la texture globale par DRX ont mis en évidence trois composantes de texture de fibre dont deux pour la matrice de Cu (<111> et <100>) et une composante unique <110> pour le Nb. On retrouve ces trois composantes de texture dans les analyses locales (EBSD), cependant les proportions relatives des composantes du Cu varient en fonction du nombre de cycles ADB.Les essais de déformation in-situ sous neutrons ont mis en évidence des comportements élasto-plastique et purement élastique des familles de grains {111} du Cu et {110} du Nb respectivement, quels que soient les échantillons. Pour la famille {200} du Cu, le comportement mécanique varie en fonction du nombre de cycles ADB. Tous ces résultats viendront nourrir les simulations effectuées dans le cadre du projet METAFORES (Thèse de Tang Gu, ENSAM-Paris/Mines ParisTech)
High strength and high conductivity Cu/Nb composites studied here are very good candidates for the design of magnets generating high pulsed magnetic fields (B ≥ 100T). They are fabricated by Accumulative Drawing and Bundling (ADB) and are constituted with a multi-scale Cu matrix embedding continuous Nb filaments that are distributed in a controlled manner. This study is performed within the framework of the METAFORES project (ANR-12-BS09-0002) aiming at assessing size and architecture effects on properties of these Cu/Nb conductors. The main purpose is therefore to characterize the microstructure and properties of these conductors at different stages of the fabrication process. Mechanical and electrical results show an increase in yield strength while maintaining adequate electrical conductivity. Global texture studies confirm three fiber texture components: two for the Cu matrix (<111> and <100>) and a single component <110 > for Nb. These three texture components are also observed at the local scale analysis (EBSD); however the volume fractions of the Cu components locally depend on the number of ADB cycles.In-situ deformation tests under neutrons reveal elasticplastic and purely elastic behaviors of the {111} Cu and {110} Nb grains family respectively, whatever the samples. However, for the {200} Cu grains family, mechanical behavior strongly depends on the number of ADB cycles. These results will feed the simulations conducted in the METAFORES project (Thesis of Tang Gu, ENSAM-Paris / Mines ParisTech)

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Sojiphan, Kittichai. "Effects of Very High Power Ultrasonic Additive Manufacturing Process Parameters on Hardness, Microstructure, and Texture of Aluminum 3003-H18 Alloy". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1418667794.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Vitero, Pérez Felipe Nicolás. "Aplicación de métodos de electro-generación de cloro activo y H2O2 al blanqueo de tejidos de algodón". Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/115486.

Testo completo

Abstract (sommario):

Previamente al ennoblecimiento textil, los tejidos de algodón son sometidos a procesos de preparación (desencolado, descrudado y blanqueo) que consiguen la eliminación de impurezas presentes en la superficie de la fibra. El presente trabajo aborda el estudio del proceso de blanqueo de tejidos de algodón crudo y descrudado, por medio de técnicas electroquímicas. Para ello se han empleado metodologías basadas en la electro-oxidación indirecta, concretamente la electro-generación de cloro activo (o electrocloración) o de H2O2 (a veces denominados electro-peroxidación) en ausencia o presencia de catalizadores de hierro (proceso electro-Fenton). En estos métodos, el agente blanqueante se forma por electrolisis de precursores inocuos (cloruro en el caso de la electro-cloración y oxígeno disuelto en el caso del H2O2), evitando el transporte, almacenaje y manipulación de sustancias peligrosas e inestables, lo que contribuye a mejorar el control, reproducibilidad y seguridad del proceso. El objetivo principal de esta Tesis Doctoral es el estudio de la influencia de diferentes variables de electrolisis en la evolución del grado de blanco, con el fin de determinar el conjunto de condiciones operacionales más adecuado para obtener un grado de blanco aceptable, considerando además las modificaciones de la estructura y composición química superficial, de la resistencia mecánica de los tejidos y el daño químico de las fibras. Estas propiedades se han analizado mediante espectroscopia de fotoelectrones emitidos por rayos X (XPS), espectroscopia infrarroja con transformada de Fourier con accesorio de reflectancia total atenuada (FTIR-ATR), microscopio electrónico de barrido (SEM), ensayos de tracción y medida del grado de polimerización. De la morfología de los tejidos, la microscopía SEM no revela alteraciones significativas tras los tratamientos de blanqueo mediante electro-generación de cloro activo. Los ensayos de XPS revelan que la relación O/C va aumentando con la duración de la electrólisis. Esto es debido a la oxidación/eliminación de impurezas no celulósicas y fenómenos de oxidación superficial, que implican un aumento de la concentración relativa de grupos funcionales de tipo C-O y C-OH. En el tratamiento 'ex situ', el índice O/C aumenta linealmente con el tiempo de proceso. En el tratamiento 'in situ' se observa un aumento brusco de la relación O/C en las fases tempranas de electrolisis y una evolución lineal posterior similar al tratamiento 'ex situ'. El índice O/C es semejante al medido en tejido blanqueados químicos con lejía y sensiblemente inferior al alcanzado en los procesos de descrudado alcalino o blanqueo químico con peróxido. El FTIR ATR confirma que el tratamiento de electro-cloración implica la eliminación de constituyentes de ceras y grasas de la superficie de las fibras de algodón, material protéico y posiblemente parte de sustancias pécticas y hemicelulosas. El cociente entre la intensidad de la banda de OH asociada al sistema de puente de hidrógeno y la intensidad de la banda de tensión C-H experimenta un aumento similar a la relación O/C determinada por XPS. No se ha logrado identificar ningún pico de fotoemisión o banda vibracional que sirva como diagnóstico del contenido de materia coloreada, ni se ha logrado establecer una correlación clara entre el aumento del grado de blanco del tejido y el cambio de los parámetros cuantitativos relativos a la composición superficial de los tejidos de algodón.
Previ al ennobliment tèxtil, els teixits de cotó són sotmesos a processos de preparació (desencolat, descruat i blanqueig) que aconsegueixen l'eliminació de les impureses presents a la superfície de la fibra. Aquest treball aborda l'estudi del procés de blanqueig de teixits de cotó cru y descruat, mitjançant tècniques electroquímiques. Per a açò s'han emprat metodologies basades en la electro-oxidació indirecta, concretament la electro-generació de clor actiu (O electrocloració) o de H2O2 (de vegades anomenada electro-peroxidació) en absència o presència de catalitzadors de ferro (procés electro-Fenton). En aquests mètodes, l'agent blanquejant es forma per l'electròlisi de precursors innocus (clorur en el cas de l'electro-cloració i oxigen dissolt en el cas del H2O2), evitant el transport, emmagatzematge i manipulació de substàncies perilloses i inestables, el que contribueix a millorar el control, reproduïbilitat i seguretat del procés. L'objectiu principal d'aquesta Tesi Doctoral és l'estudi de la influència de diferents variables d'electròlisi en l'evolució del grau de blanc, amb el fi de determinar el conjunt de condicions operacionals més adequat per a obtenir un grau de blanc acceptable, considerant-se amés les modificacions de l'estructura i composició química superficial, de la resistència mecànica dels teixits, i del dany químic de les fibres. Aquestes propietats s'han analitzat mitjançant espectroscòpia de fotoelectrons emesos per rajos X (XPS), espectroscòpia infraroja b transformada de Fourier amb accessori de reflectància total atenuada (FTIR-ATR), microscopi electrònic d'escombrat (SEM), assajos de tracció i mesura del grau de polimerització. De la morfologia dels teixits, la microscòpia SEM no revela alteracions significatives després dels tractaments de blanqueig mitjançant electró-generació de clor actiu. Els assajos de XPS revelen que la relació O/C va augmentant amb la durada de l'electròlisi. Aquest fet es deu a la oxidació/eliminació de impureses no cel·lulòsiques i fenòmens d'oxidació superficial, que impliquen un augment de la concentració relativa de grups funcionals del tipus C-O i C-OH. Al tractament 'ex situ', 'l'índex O/C augmenta linealment amb el temps de procés. Al tractament 'in situ' s'observa un augment brusc de la relació O/C a les fases primerenques de l'electròlisi i una evolució lineal posterior similar al tractament 'ex situ'. L'índex O/C es semblant al mesurat a teixits blanquejats químicament amb lleixiu i sensiblement inferior a l'assolit als processos de descruat alcalí o blanqueig químic amb peròxid. El FTIR ATR confirma que el tractament d'electro-cloració implica l'eliminació de constituents de ceres i greixos de la superfície de les fibres de cotó, material proteic i possiblement part de substàncies pèctiques i hemicel·luloses. El quocient entre la intensitat de la banda OH associada al sistema pont d'hidrogen i la intensitat de la banda de tensió C-H experimenta un augment similar a la relació O/C determinada per XPS. No s'ha aconseguit identificar cap pic de fotoemissió o banda vibracional que serveixi com a diagnòstic del contingut de matèria acolorida, ni s'ha aconseguit establir una correlació clara entre l'augment del grau de blanc del teixit i el canvi dels paràmetres quantitatius relatius a la composició superficial dels teixits de cotó.
Prior to the textile finishing, cotton fabrics are subjected to preparation processes (desizing, scouring and bleaching) in order to remove noncellulosic impurities present on the fiber surface. The present work deals with the study of the bleaching process of raw and scoured cotton fabrics by means of electrochemical techniques. To this end, methodologies based on indirect electro-oxidation have been used, namely the electro-generation of active chlorine (or electro-chlorination) or H2O2 (sometimes called electro-peroxidation) in the absence or presence of iron catalysts (electro-Fenton process). In these methods, the bleaching agent is formed by electrolysis of harmless precursors (chloride in the case of electro-chlorination and dissolved oxygen in the case of H2O2), thus avoiding the transport, storage and handling of hazardous and unstable substances, which contributes to improve the control, reproducibility and safety of the process. The main objective of this Doctoral Thesis is the study of the influence of different electrolysis variables on the evolution of the whiteness index, in order to determine the most suitable set of operational conditions to obtain an acceptable whiteness index, considering also the modifications of the structure and chemical composition of the surface, of the mechanical resistance of the cotton fabrics and the chemical damage of the fibers. These properties have been analyzed by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy with attenuated total reflectance accessory (ATR-FTIR), scanning electron microscope (SEM), tensile tests and degree of polymerization. As to the morphology of the textile cotton fabric, SEM microscopy reveals no significant modifiations after the bleaching treatments by electro-generation of active chlorine. The XPS tests reveal that the O/C ratio increases with the duration of electrolysis. This is attributed to the oxidation/elimination of non-cellulosic impurities and superficial oxidation phenomena, which involve an increase in the relative concentration C-O and C-OH functional groups. In the 'ex situ' treatment, the O/C index increases linearly with the process time. In the 'in situ' treatment an abrupt increase in the O/C ratio in the early stages of electrolysis and a subsequent linear evolution similar to the 'ex situ' treatment are observed. The O/C index is similar to that measured in cotton fabrics treated with bleach, but it is significantly lower than those achieved in alkaline scouring or peroxide chemical bleaching processes. The ATR-FTIR confirms that the electro-chlorination treatment involves the elimination of constituents of waxes and fats from the surface of cotton fibers, together with proteins and possibly part of pectic and hemicellulosic substances. The ratio of the OH stretching intensity associated with the cellulose hydrogen-bonding system to the C-H stretching intensity undergoes an increase similar to the O/C ratio as determined by XPS. We could not find any any photoemission peak or vibrational band as a diagnostic signal of the content of colored matter; nor has it been possible to establish a clear correlation between the increase in the whiteness index of the bleached cotton fabrics and the change in the quantitative parameters relative to their surface composition.
Vitero Pérez, FN. (2018). Aplicación de métodos de electro-generación de cloro activo y H2O2 al blanqueo de tejidos de algodón [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/115486
TESIS

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Varanytsia, Andrii. "Augmenting Electro-Optic and Optical Behavior of Cholesteric and Nematic Liquid Crystals". Kent State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=kent1532526040658373.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Hennequin, Didier. "Composition, structure et texture des fromages à pate molle : une analyse multidimensionnelle pour une approche scientifique de l'innovation". Vandoeuvre-les-Nancy, INPL, 1993. http://www.theses.fr/1993INPL001N.

Testo completo

Abstract (sommario):

L'analyse des relations entre la composition, la structure et la texture des fromages à pate molle constitue la base de cette étude. La méthodologie utilisée a pour but de classer scientifiquement, au moyen de critères objectifs, les fromages à pate molle parmi les autres catégories de fromages. Une première partie de l'étude est consacrée à la caractérisation des propriétés texturales des fromages en relation avec leur composition physicochimique. Dans ce but, des méthodes rhéologiques et d'évaluation sensorielle ont été mises en œuvre. Le traitement statistique des résultats permet de situer objectivement les fromages sur des représentations graphiques de leurs propriétés texturales. L'analyse de la microstructure des fromages est abordée dans une deuxième partie. La microscopie électronique à balayage (MEB) permet de relier les caractéristiques structures des fromages a leurs propriétés texturales. L'influence de la composition sur la structure est quantifiée par la technique d'analyse d'images. Par ailleurs, la technique de cisaillement sous contrainte normale imposée donne des informations sur le degré de liaison de la caille. L'ensemble des résultats constitue une aide à l'innovation en particulier pour la définition et l'optimisation technologique de produits originaux et pour la reformulation de certains types de fromages

Gli stili APA, Harvard, Vancouver, ISO e altri

Tesi sul tema "Textile Electrode"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili