scholarly journals Mechanical phase inversion of Pickering emulsions via metastable wetting of rough colloids

Soft Matter ◽  
2019 ◽  
Vol 15 (39) ◽  
pp. 7888-7900 ◽  
Author(s):  
Michele Zanini ◽  
Alberto Cingolani ◽  
Chiao-Peng Hsu ◽  
Miguel Ángel Fernández-Rodríguez ◽  
Giuseppe Soligno ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Phase Inversion ◽  
Mechanical Energy ◽  
Pickering Emulsions ◽  
Energy Inputs ◽  
Wetting Hysteresis

We exploit the surface-roughness-induced wetting hysteresis of individual colloids to achieve Pickering emulsions undergoing phase inversion upon mechanical energy inputs.

Responses of Sea-Ice Microalgae to Climatic and Fortnightly Tidal Energy Inputs (Manitounuk Sound, Hudson Bay)

1985 ◽  
Vol 42 (5) ◽  
pp. 999-1006 ◽  
Author(s):  
M. Gosselin ◽  
L. Legendre ◽  
S. Demers ◽  
R. G. Ingram
Keyword(s):  
Light Intensity ◽  
Sea Ice ◽  
Light Adaptation ◽  
Mechanical Energy ◽  
Vertical Mixing ◽  
Tidal Energy ◽  
Tidal Mixing ◽  
Hudson Bay ◽  
Energy Inputs ◽  
Ice Water

Variations of sea-ice microalgae at the ice–water interface (Manitounuk Sound, Hudson Bay, Canada) were studied in relation to various energy inputs (light, tidal mixing, and heat) in April and May 1982. Seasonal photosynthetic activity does not start before the light intensity reaches 7.6 μEinst∙m−2∙s−1. Above this value, the seasonal increase in cell numbers and chlorophyll and in the photoadaptation index (Ik) is related to the increase in underice light intensity. The sea-ice community changes from shade to light adaptation to optimize the use of ambient light energy. Photosynthetic efficiency (αB) is mainly controlled by the fortnightly tidal vertical mixing, which governs the amount of phosphate (or of another nutrient factor) in the upper brackish layer. The ice microflora, which grows at a stable interface, takes advantage of nutrient replenishment during mixed water column conditions. We conclude that production of microalgae depends upon three forms of energy: (1) the flux of solar light, (2) the inputs of auxiliary mechanical energy (here, the fortnightly tides), and (3) the energy exchanges (here, the heat flux) responsible for the maintenance or destruction of energetic interfaces (ergoclines).

Effects of starch nanoparticles on phase inversion of Pickering emulsions

2018 ◽  
Vol 96 (5) ◽  
pp. 1089-1097 ◽  
Author(s):  
Sileola B. Ogunlaja ◽  
Rajinder Pal ◽  
Kaveh Sarikhani
Keyword(s):  
Phase Inversion ◽  
Pickering Emulsions ◽  
Starch Nanoparticles

scholarly journals Engineering hybrid microgel as particulate emulsifier for reversible Pickering emulsions

2021 ◽  
Author(s):  
To Ngai ◽  
Hang Jiang ◽  
Shengwei Zhang ◽  
Guanqing Sun ◽  
Yunxing Li ◽  
...  
Keyword(s):  
Phase Inversion ◽  
The State ◽  
Pickering Emulsions ◽  
Stimuli Sensitive

Thermo-responsive microgels are unique stabilizers for stimuli-sensitive Pickering emulsions that can be switched between the state of emulsification and demulsification by changing temperature. However, directly temperature-triggering phase inversion of microgel...

In-Process Laser Re-Melting of Thin Walled Parts to Improve Surface Quality after Laser Metal Deposition

2019 ◽  
Vol 813 ◽  
pp. 191-196
Author(s):  
Francesco Bruzzo ◽  
Guendalina Catalano ◽  
Ali Gökhan Demir ◽  
Barbara Previtali
Keyword(s):  
Surface Roughness ◽  
Energy Density ◽  
Surface Quality ◽  
Metal Deposition ◽  
Laser Metal Deposition ◽  
Average Roughness ◽  
Thin Walls ◽  
Energy Inputs ◽  
Thin Walled

Laser metal deposition (LMD) is an additive manufacturing process highly adaptable to medium to large sized components with bulky structures as well as thin walls. Low surface quality of as-deposited LMD manufactured components with average roughness values (Ra) around 15-20μm is one of the main drawbacks that prevent the use of the part without the implementation of costly and time-consuming post-processes. In this work laser re-melting is applied right after LMD process with the use of the same equipment used for the deposition to treat AISI 316L thin walled parts. The surface quality improvement is assessed through the measurement of both areal surface roughness Sa(0.8mm) QUOTE and waviness Wa QUOTE (0.8mm) parameters. Moreover, roughness power spectrum is used to point out the presence of principal periodical components both in the as-deposited and in the re-melted surfaces. Then, the transfer function is calculated to better understand the effects of laser re-melting on the topography evolution, measuring the changes of individual components contributing to the surface roughness such as the layering technique and the presence of sintered particles. Experiments showed that while low energy density inputs are not capable to properly modify the additive surface topography, excessive energy inputs impose a strong periodical component with wavelength equal to the laser scan spacing and directionality determined by the used strategy. When a proper amount of energy density input is used, laser re-melting is capable to generate smooth isotropic topographies without visible periodical surface structures.

Mount Etna and the 1971 eruption - Rheological features of the 1971 Mount Etna lavas

1973 ◽  
Vol 274 (1238) ◽  
pp. 99-106 ◽  
Keyword(s):  
Surface Roughness ◽  
Reynolds Number ◽  
Laminar Flow ◽  
Mechanical Energy ◽  
Critical Value ◽  
Heat Energy ◽  
Mount Etna ◽  
Two Dimensional ◽  
Spiral Motion ◽  
Rapid Transition

Rheological studies on the 1971 M ount Etna lavas indicate they underwent rapid transition from Newtonian to non-Newtonian fluids near their point of emission and that the non-Newtonian regime may be coincidental with high mechanical energy/low heat energy regime further from the boccas. Darcy’s equation quantifies the surface roughness of channels using the Chezy coefficient and is plotted against Reynolds number on a Stanton diagram. The relation is linear, and the critical value Re0 is not exceeded, proving wholly laminar flow. The lava underwent a divergent, twin spiral motion involving two dimensional laminar flow. Convergent, twin spiral motion occurred only where lava passed through a constriction at a relatively high velocity.

Near-Infrared Spectroscopic Measurements of Structural Changes in Starch-Containing Extruded Products

1996 ◽  
Vol 50 (9) ◽  
pp. 1134-1139 ◽  
Author(s):  
S. Millar ◽  
P. Robert ◽  
M. F. Devaux ◽  
R. C. E. Guy ◽  
P. Maris
Keyword(s):  
Structural Changes ◽  
Near Infrared ◽  
Mechanical Energy ◽  
Principal Component ◽  
Physical Structure ◽  
Extrusion Cooking ◽  
Absorption Bands ◽  
Energy Inputs ◽  
Specific Mechanical Energy ◽  
Extruded Products

Near-infrared spectroscopy was evaluated as a means of following physical and chemical changes in starch during the extrusion cooking of wheat flour under the Measurements and Testing Program of the European Commission. With the use of principal component (PC) and canonical correlation (CC) analyses, samples could be classified according to the severity of the extrusion cooking conditions. An interpretation of the spectra showed that the different processing conditions modified the physical structure of the starch molecules. At low values of specific mechanical energy inputs, starch was partially crystalline and the near-infrared spectra exhibited characteristic absorption bands at about 1428, 1520, and 1587 nm. As the energy inputs increased, causing a change to molten starch, the intensity of the bands at 1520 and 1587 nm decreased, with a shift of the 1428-nm absorption band towards longer wavelengths also being observed. The changes that occurred were thought to be due to a disruption of the intra- and intermolecular hydrogen bonding of the starch. At the higher levels of specific mechanical energy inputs, the starch molecules underwent further structural modification, resulting in their partial degradation.

Phase Inversion of Pickering Emulsions by Electrolyte for Potential Reversible Water-in-Oil Drilling Fluids

2020 ◽  
Vol 34 (2) ◽  
pp. 1317-1328 ◽  
Author(s):  
Lu Liu ◽  
Xiaolin Pu ◽  
Yan Zhou ◽  
Xiaodong Wu ◽  
Dan Luo ◽  
...  
Keyword(s):  
Phase Inversion ◽  
Drilling Fluids ◽  
Pickering Emulsions ◽  
Oil Drilling

scholarly journals Structure and rheology during catastrophic phase inversion of Pickering emulsions stabilized with fumed silica particles

2020 ◽  
Vol 593 ◽  
pp. 124630
Author(s):  
Frederico Macedo Fernandes Barros ◽  
Christophe Chassenieux ◽  
Marli Miriam de Souza Lima ◽  
Lazhar Benyahia
Keyword(s):  
Fumed Silica ◽  
Phase Inversion ◽  
Silica Particles ◽  
Pickering Emulsions

Tensiometric studies on wetting. I. Some effects of surface roughness (theoretical)

1981 ◽  
Vol 59 (13) ◽  
pp. 1954-1961 ◽  
Author(s):  
Erdal Bayramli ◽  
Theodore G. M. van de Ven ◽  
Stanley G. Mason
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Contact Angle Hysteresis ◽  
Solid Surfaces ◽  
Surface Slopes ◽  
Receding Contact ◽  
Receding Contact Angle ◽  
Wetting Hysteresis ◽  
Non Equilibrium ◽  
Roughness Size

The effect of roughness on the wettability of an axisymmetric cylinder is investigated theoretically by making use of equilibrium meniscus shapes on solid surfaces analogously to previous studies for drops on horizontal surfaces. Employing circumferential sinusoidal and saw-toothed grooved structure, and using mechanistic arguments, one can explain wetting hysteresis, the formation of composite surfaces, and the presence of non-equilibrium jumps during contact line motion.On unidirectionally random surfaces the maximum surface slopes mainly determine the value of the advancing, and the minimum slopes of the receding contact angle. These effects of surface slopes diminish with decreasing roughness size. Diminishing roughness size also gives rise to numerous small non-equilibrium jumps imposed upon larger jumps during wetting. The contact angle hysteresis is found to show a nearly linear relationship with the spread in the distribution of solid surface slopes.

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