Role of dispersed phase in the creep of ferritic steels

1989 ◽  
Vol 39 (10) ◽  
pp. 1133-1137 ◽  
Author(s):  
Václav Foldyna ◽  
Jaroslav Purmenský
Keyword(s):  
Ferritic Steels ◽  
Dispersed Phase

The role of dispersed phase morphology on toughening of epoxies

Polymer ◽  
1997 ◽  
Vol 38 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Julie Y. Qian ◽  
Raymond A. Pearson ◽  
Victoria L. Dimonie ◽  
Olga L. Shaffer ◽  
Mohamed S. El-Aasser
Keyword(s):  
Phase Morphology ◽  
Dispersed Phase

The Role of Excess Attractive Particles in the Elasticity of High Internal Phase Pickering Emulsions

Soft Matter ◽  
2021 ◽  
Author(s):  
Junsu Chae ◽  
Siyoung Choi ◽  
KyuHan Kim
Keyword(s):  
Volume Fraction ◽  
Dispersed Phase ◽  
Pickering Emulsions ◽  
High Internal Phase Emulsion ◽  
Internal Phase

A high internal phase emulsion (HIPE), which has a volume fraction of dispersed phase of over 74%, shows a solid like property because of concentrated polyhedral droplets. Although many studies...

scholarly journals Veiled Extra Virgin Olive Oils: Role of Emulsion, Water and Antioxidants

2020 ◽  
Vol 4 (3) ◽  
pp. 38
Author(s):  
Giuseppe Cinelli ◽  
Martina Cofelice ◽  
Francesco Venditti
Keyword(s):  
Olive Oil ◽  
Current Knowledge ◽  
Virgin Olive Oil ◽  
Extra Virgin Olive Oil ◽  
Bioactive Molecules ◽  
Dispersed Phase ◽  
Colloidal System ◽  
Oil Processing

This review traces the current knowledge on the effects of various factors and phenomena that occur at interface, and the role of dispersed phase on the physicochemical, sensorial and nutritional characteristics of veiled extra virgin olive oil (VVOO). Since 1994 there have been numerous articles in the literature regarding the peculiar characteristic of unfiltered olive oil, so-called veiled or cloud virgin olive oil. It is a colloidal system (emulsion–sol), where the continuous lipidic phase dispreads mini droplets of milling water, fragments of cells and biotic fraction obtained from oil processing. During storage, the dispersed phase collapses and determines the quality of the virgin olive oil (VOO). The observed phenomena lead to worsening the quality of the product by causing defects such as oxidation of phenols, triacylglycerols hydrolysis and off-flavor formation. The addition of bioactive compounds, such as vitamins, on product based on VVOO, must take into account the eventual synergistic effect of individual substances. The role of the interphase is crucial to the synergic activity of bioactive molecules in improving oxidative stability, sensorial and health characteristics of VVOO.

An Assessment of Low Alloy Steel EAC Corrosion Fatigue Relationships for BWR Environment

2005 ◽  
Author(s):  
Hardayal Mehta ◽  
Ron Horn
Keyword(s):  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Water Chemistry ◽  
Crack Growth ◽  
Corrosion Fatigue ◽  
Growth Rates ◽  
Ferritic Steels ◽  
Asme Code ◽  
Crack Growth Rates

The fatigue crack growth rates for ferritic steels in water environments given in A-4300 of Appendix A, Section XI, ASME Code, were developed from data obtained prior to 1980. Subsequently, updated assessments by Eason, et al. and recent laboratory test results from Seifert and Ritter demonstrated that under certain conditions, ferritic steels exposed to oxygenated water environments may be susceptible to high fatigue crack growth rates that exceed the current disposition curves. In the light of ASME adopting Code Case N-643 for PWRs, there is a need for a similar Code Case for the BWR water environments (for both the normal water chemistry and hydrogen water chemistry/NobleChem) that takes into account these findings. This could mean modification of current EAC curves in the ASME Code. A joint program of EPRI and GE was developed to address this need for updated evaluations of the corrosion fatigue. The program’s first task has been to re-assess the role of rise time, environment, alloy, heat treatment and impurity levels on the established ASME codified disposition curves/methodologies. The data was then used as a basis to assess the impact of on modified cyclic curves on the disposition approaches that are currently used to evaluate postulated flaws in the BWR reactor pressure vessel or RPV head and the feed water nozzle regions. The presentation would include a discussion of the appropriate BWR plant transients and the GE process for performing evaluations. The role of the evaluations on the establishment of inspection intervals currently determined using NUREG-0619 and the latest BWROG Report would also be presented. Finally, the relationship between cyclic load and constant load behavior in these steels are discussed in the context of the mechanisms for environmentally assisted cracking.

Investigation on Corrosion Base Characteristics and Deep Dehydration Technology of Micro-Droplets in Oil Pipelines

2019 ◽  
Author(s):  
Kai Guo ◽  
Yuling Lv ◽  
Limin He ◽  
Xiaoming Luo ◽  
Donghai Yang
Keyword(s):  
Particle Size ◽  
Electric Field ◽  
Crude Oil ◽  
Pitting Corrosion ◽  
Dispersed Phase ◽  
Water Droplets ◽  
Size Change ◽  
Long Distance ◽  
Oil Pipelines

Abstract Corrosion is an important cause of steel pipeline failure and oil leakage, especially local pitting corrosion in long distance crude oil pipelines. Deep dehydration is of great significance to pipeline anticorrosion, however, further experimental results show that it is very difficult to achieve deep dehydration by a single electric field. Recent studies have shown that the particle size change of dispersed phase for the emulsion with large droplets after electromagnetic synergistic treatment is more obvious than that of a single electric field. In this study, the effect of micro-droplets on corrosion of oil pipelines are revealed. The role of micro-droplets in the process of microbial corrosion and electrochemical corrosion in a strong or weak acid solution for oil pipelines was summarized. A structural model of on-line tubular electromagnetic synergistic intensification coalescing device was established. The size change of particle of the dispersed phase in emulsions was studied. Crude oil and water were used as experimental materials, and the particle size distribution of dispersed phase in emulsions was tested by the evaluation system. The results showed that mean radius, d10 and d50 of water droplets in emulsion treated by electromagnetic synergism are larger than those treated by a single electric field. Strengthening droplets coalescence by electromagnetic synergism is also effective on emulsions whose particle size of the dispersed phase is less than 100μm. The role of micro-droplets in pitting corrosion is summarized based on corrosion channels. In the process of microbial corrosion and electrochemical corrosion in strong or weak acid solution, the role of water is presented in two aspects like participating in the reaction and providing ion electron transmission media. Analogous to culture medium, micro water droplets can be called corrosion medium for pitting corrosion in long-distance crude oil pipelines. A structural model of on-line tubular electromagnetic synergistic intensification coalescing device was established, including an electric field generation device and a magnetic field excitation component with orthogonal distribution and synchronous synergy. And emulsions are treated by electric and magnetic fields while flowing through the medium channel. The particle size change of dispersed phase in emulsions with average particle size of dispersed phase less than 100μm was experimental studied. It is found that mean radius, d10 and d50 of water droplets in emulsion treated by electromagnetic synergism are larger than that by a single electric field. Therefore, electromagnetic synergism can further enhance the dehydration depth compared with a single electric field.

The Influence of Base Oil and Thixotropy on Magnetorheological Property of MRF

2013 ◽  
Vol 320 ◽  
pp. 19-24
Author(s):  
Jian Jian Yang ◽  
Hua Yan ◽  
Zhi De Hu ◽  
Shi Xiang Xu
Keyword(s):  
Shear Stress ◽  
Shear Rate ◽  
Magnetorheological Fluid ◽  
Mineral Oil ◽  
Dispersed Phase ◽  
Zero Field ◽  
Rotational Viscometer ◽  
Base Oil ◽  
Low Shear

Adopting carbonyl iron powder and silicone/mineral oil as suspend phase and dispersed phase separately,and silica, kaolin as lubricant additives,magnetorheological (MR) fluid was prepared by ball milling. The apparent viscosity of base oil and shear stress were measured on a modified rotational viscometer. The experimental results demonstrated that an appropriate viscosity of base oil contributed to the rheology of MRF. Adding a small amount of thixotropy into MRF had little influence on zero-field viscosity, which facilitated the application of MRF to maintain adequate liquidity. Under low shear rate conditions, the shear stress was improved by adding thixotropy to some extent, especially in the mineral oil-based magnetorheological fluid, in which the role of silica was superior to kaolin.

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