Rheology and Fourier-Transform Rheology on Water-Based Systems

Rheology and Fourier-Transform Rheology on Water-Based Systems PDF

Author: Christopher Klein

Publisher: Logos Verlag Berlin GmbH

Published: 2008

Total Pages: 249

ISBN-13: 3832519882

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The influence of shear fields on water-based systems was investigated within this thesis. The non-linear rheological behaviour of spherical and rod-like particles was examined with Fourier-Transform rheology under LAOS conditions. As a model system for spherical particles two different kinds of polystyrene disper- sions, with a solid content higher than 0.3 each, were synthesised within this work. Due to the differences in polydispersity and Debye-length, differences were also found in the rheology. In the FT-rheology both kinds of dispersions showed a similar rise in the intensities of the magnitudes of the odd higher harmonics, which were predicted by a model. The, in some cases additionally appearing second harmonics, were not predicted. A novel method to analyse the time domain signal was developed, that splits the time domain signal up in four characteristic functions. Those characteristic functions correspond to rheological phenomena. In some cases the intensities of the Fourier components can interfere negatively. FD-virus particles were used as a rod-like model system, which already shows a highly non-linear behaviour at concentrations below 1. % wt. Predictions for the dependence of the higher harmonics from the strain amplitude described the non-linear behaviour well at large, but no so good at small strain amplitudes. Ad- ditionally the trends of the rheological behaviour could be described by a theory for rod-like particles. An existing rheo-optical set-up was enhanced by reducing the background birefringence by a factor of 20 and by increasing the time resolution by a factor of 24. Additionally a combination of FT-rheology and rheo-optics was achieved. The influence of a constant shear field on the crystallisation process of zinc oxide in the presence of a polymer was examined. The crystallites showed a reduction in length by a factor of 2. The directed addition of polymers in combi- nation with a defined shear field can be an easy way for a defined change of the form of crystallites.

Rheology and Fourier-transform Rheology on Water-based Systems

Rheology and Fourier-transform Rheology on Water-based Systems PDF

Author:

Publisher:

Published: 2005

Total Pages:

ISBN-13:

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The influence of shear fields on water-based systems was investigated within this thesis. The non-linear rheological behaviour of spherical and rod-like particles was examined with Fourier-Transform rheology under LAOS conditions. As a model system for spherical particles two different kinds of polystyrene dispersions, with a solid content higher than 0.3 each, were synthesised within this work. Due to the differences in polydispersity and Debye-length, differences were also found in the rheology. In the FT-rheology both kinds of dispersions showed a similar rise in the intensities of the magnitudes of the odd higher harmonics, which were predicted by a model. The in some cases additionally appearing second harmonics were not predicted. A novel method to analyse the time domain signal was developed, that splits the time domain signal up in four characteristic functions. Those characteristic functions correspond to rheological phenomena. In some cases the intensities of the Fourier components can interfere negatively. FD-virus particles were used as a rod-like model system, which already shows a highly non-linear behaviour at concentrations below 1. % wt. Predictions for the dependence of the higher harmonics from the strain amplitude described the non-linear behaviour well at large, but no so good at small strain amplitudes. Additionally the trends of the rheological behaviour could be described by a theory for rod-like particles. An existing rheo-optical set-up was enhanced by reducing the background birefringence by a factor of 20 and by increasing the time resolution by a factor of 24. Additionally a combination of FT-rheology and rheo-optics was achieved. The influence of a constant shear field on the crystallisation process of zinc oxide in the presence of a polymer was examined. The crystallites showed a reduction in length by a factor of 2. The directed addition of polymers in combination with a defined shear field can be an easy way for a defined change of t.

Fourier Transform Rheology on Dispersions Based on Newtonian Fluids

Fourier Transform Rheology on Dispersions Based on Newtonian Fluids PDF

Author: Kathrin Reinheimer

Publisher: Logos Verlag Berlin GmbH

Published: 2012

Total Pages: 200

ISBN-13: 3832531386

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Dispersionen sind ein heterogenes Gemisch aus zwei Stoffen, die sich nicht miteinander mischen. In der vorliegenden Arbeit werden sowohl Suspensionen bestehend aus einer festen dispersen Phase in einem flussigen Dispersionsmedium, Emulsionen bestehen aus zwei nicht mischbaren Flussigkeiten als auch Schaume, gebildet aus einer Gasphase dispergiert in einer Flussigkeit, untersucht. Als Hauptcharakterisierungsmethode dient die Fourier Transformations-Rheologie (FT-Rheologie), welches eine mechanische Charakterisierungsmethode im nichtlinearen Bereich darstellt.

Techniques in Rheological Measurement

Techniques in Rheological Measurement PDF

Author: A.A. Collyer

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 346

ISBN-13: 9401121141

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In an earlier book, Rheological Measurement (A. A. Collyer & D. W. Clegg, Elsevier Applied Science, 1988), the basic rheological methods of measurement presently used were discussed in the light of the basic underlying principles and current theories. The same approach is adopted in this companion book, which is concerned with some newer or more sophisticated techniques that have resulted from a fresh understanding of the subject, or as a result of improvement in computer control, data acquisition and computational power, or more simply from an industrial need, particularly with regard to process control. The first two chapters deal with the extensional flow properties of fluids and their measurement. This inclusion is in response to a greater awareness in industry of the importance of these flows. Chapter 3 intro duces and develops the subject of surface rheology and the measurement of its properties, again a subject of increasing significance. The methods of measurement of the dynamic mechanical properties of fluids and the calculation of the resulting rheological parameters are discussed in Chap ters 4-7 inclusive. The subject areas covered are: large-amplitude oscilla tory shear, a model for viscoelastic fluids and solids, a new method of measuring dynamic mechanical properties, particularly for curing sys tems, and the use of complex waveforms in dynamic mechanical analysis.

Rheology and Quality Research of Cereal-Based Food

Rheology and Quality Research of Cereal-Based Food PDF

Author: Anabela Raymundo

Publisher: MDPI

Published: 2021-06-21

Total Pages: 132

ISBN-13: 3036505040

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New trends in the cereal industry deal with the persistent need to develop new food goods tailored to consumer requirements and, in the near future, to the scarcity of food resources. Concepts of sustainable food production and food products as health and wellness promoters, the use of organic ingredients such as new ancient cereals to produce redesigned old staple foods, or the use of byproducts in designed food or feed formulations, in accordance with the bioeconomy and sustainability principles, are current topics that act as driving forces for innovation. The structure of cereal-based food products, especially in the case of gluten- or wheat-free foods, has proven to be a determinant for food appeal and strongly impacts consumer acceptance. It is well known that products with the same chemical composition can present very different structures, resulting in differently perceived texture and sensory properties and, therefore, rheology is an important tool for the food cereal industries. These are topics that act as driving forces for innovation and will be discussed in the present Special Issue.

Polymer Physics

Polymer Physics PDF

Author: Leszek A. Utracki

Publisher: John Wiley & Sons

Published: 2011-02-14

Total Pages: 677

ISBN-13: 1118062957

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Providing a comprehensive review of the state-of-the-art advanced research in the field, Polymer Physics explores the interrelationships among polymer structure, morphology, and physical and mechanical behavior. Featuring contributions from renowned experts, the book covers the basics of important areas in polymer physics while projecting into the future, making it a valuable resource for students and chemists, chemical engineers, materials scientists, and polymer scientists as well as professionals in related industries.

Electrorheological Fluids And Magnetorheological Suspensions (Ermr 2004) - Proceedings Of The Ninth International Conference

Electrorheological Fluids And Magnetorheological Suspensions (Ermr 2004) - Proceedings Of The Ninth International Conference PDF

Author: Kunquan Lu

Publisher: World Scientific

Published: 2005-06-14

Total Pages: 1013

ISBN-13: 9814481181

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This volume covers the most recent progress of research work on electrorheological (ER) and magnetorheological (MR) industrial applications related to controllable damping, ER/MR fundamental mechanisms, and understanding the potential of new classes of field responsive materials.The proceedings have been selected for coverage in:• Materials Science Citation Index®• Index to Scientific & Technical Proceedings® (ISTP® / ISI Proceedings)• Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings)• CC Proceedings — Engineering & Physical Sciences

Science and Technology of Fibers in Food Systems

Science and Technology of Fibers in Food Systems PDF

Author: Jorge Welti-Chanes

Publisher: Springer Nature

Published: 2020-04-15

Total Pages: 464

ISBN-13: 3030386546

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This text provides comprehensive coverage of fibers used in food formulations, starting with the understanding of their basic chemical structure and how they are present and organized in the cell wall structure, their physicochemical and functional properties, their impact on the digestive process and their role and preventive action against various chronic diseases including colon cancer. The book focuses on traditional and new fiber rich sources, incorporating an integrated approach in terms of the technological and engineering processes used to obtain and incorporate them in traditional foods, plus their characterization, extraction and modification. The study of processing conditions including the chemical, physical and enzymatic processes of fiber extraction and modification are also covered, including traditional and emerging processing technologies, plus the application of fibers in the development of new products and processes. Science and Technology of Fibers in Food Systems integrates knowledge of fibers from their basic structural and property aspects and the applications of these ingredients to extraction process analysis, modification and feasibility for use at the industry level. The chapters incorporate the physiological aspects related to the consumption of fiber for prevention of serious diseases.

Flow and Transport Properties of Unconventional Reservoirs 2018

Flow and Transport Properties of Unconventional Reservoirs 2018 PDF

Author: Jianchao Cai

Publisher: MDPI

Published: 2019-07-23

Total Pages: 364

ISBN-13: 3039211161

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Unconventional reservoirs are usually complex and highly heterogeneous, such as shale, coal, and tight sandstone reservoirs. The strong physical and chemical interactions between fluids and pore surfaces lead to the inapplicability of conventional approaches for characterizing fluid flow in these low-porosity and ultralow-permeability reservoir systems. Therefore, new theories and techniques are urgently needed to characterize petrophysical properties, fluid transport, and their relationships at multiple scales for improving production efficiency from unconventional reservoirs. This book presents fundamental innovations gathered from 21 recent works on novel applications of new techniques and theories in unconventional reservoirs, covering the fields of petrophysical characterization, hydraulic fracturing, fluid transport physics, enhanced oil recovery, and geothermal energy. Clearly, the research covered in this book is helpful to understand and master the latest techniques and theories for unconventional reservoirs, which have important practical significance for the economic and effective development of unconventional oil and gas resources.