Spontaneous inversion of the submicron ceramic layer deposited on steel and the copper droplet positioned on their top (case of ceramic poorly wetted by liquid Cu)

In this paper, 50 … 680 nm thick AlN-Al2O3 coatings are deposited by magnetron sputtering on the surface of a steel substrate and a piece of copper is melted on top of the ceramic. Upon heating the ceramic layer is cracked, and the phase inversion of the two top phases from steel/ceramic/copper configuration to the steel/copper/ceramic configuration takes place within 30 s of liquid time of copper. This phase inversion process is accompanied by a Gibbs energy change of about − 1.78 J/m2, due to good wettability of solid deoxidized steel by liquid copper in contrary to poor wettability of the ceramic by the copper. When copper is melted on AlN-Al2O3 coating with its thicknesses smaller than a critical value of about 170 ± 60 nm, liquid copper droplets hanging down into the cracks within the ceramic reach the solid steel surface at the bottom of the cracks, thus the flow of Cu down along the cracks is enabled. However, when copper is melted on AlN-Al2O3 with its thickness larger than the critical value of 170 ± 60 nm, Cu first forms a non-wetting droplet on top of the ceramics, and only after a certain incubation time it starts flowing down the cracks. This incubation time was found to depend linearly on the thickness of the ceramic, as cracks are filled from the bottom upwards by liquid copper via the evaporation–condensation mechanism. By the end of the process, the steel/copper/ceramic configuration is further stabilized by gravity. Graphical abstract

Heavy Loaded Parts of Petrochemical Equipment Destruction Cause Investigation

The problem of using specialized passivating metals and alloys lies in a rather narrow range of the protecting film performance. With a slight change in operating conditions, the film is destroyed and an avalanche-like process of local corrosion begins at the place of film breakdown. A sequence has been developed for determining parts destruction causes, including a sequential analysis of operating conditions; nature of the part destruction; corrosion products composition; phase inversion in the alloy during overheating or mechanical stress in the part.

Cellulose Blended Membranes for High-Salinity Water Pervaporation Desalination

In the current study, cellulose acetate (CA)/cellulose triacetate (CTA) nanocomposite membranes blended with zirconium dioxide (ZrO2) are prepared via phase inversion for pervaporation desalination performance. ZrO2 nanoparticles are added to enhance the hydrophilicity and porosity of the nanocomposite membranes. The fabricated nanocomposite membranes are characterized by SEM, FTIR, TGA, and DSC to study the surface morphology, chemical composition, thermal stability and strength. Nanocomposite membranes’ performance for pervaporation desalination is assessed as a function of feed concentration. Pervaporation results revealed that the nanocomposite membrane consisting of 2% ZrO2 achieved a maximum water flux of 6.5 kg/m2h, whereas the salt rejection was about 99.8%.

Statistical Analysis of Synthesis Parameters to Fabricate PVDF/PVP/TiO2 Membranes via Phase-Inversion with Enhanced Filtration Performance and Photocatalytic Properties

Non-solvent induced phase-inversion is one of the most used methods to fabricate membranes. However, there are only a few studies supported by statistical analysis on how the different fabrication conditions affect the formation and performance of membranes. In this paper, a central composite design was employed to analyze how different fabrication conditions affect the pure water flux, pore size, and photocatalytic activity of polyvinylidene fluoride (PVDF) membranes. Polyvinylpyrrolidone (PVP) was used to form pores, and titanium dioxide (TiO2) to ensure the photocatalytic activity of the membranes. The studied bath temperatures (15 to 25 °C) and evaporation times (0 to 60 s) did not significantly affect the pore size and pure water flux of the membranes. The concentration of PVDF (12.5 to 17.5%) affected the viscosity, formation capability, and pore sizes. PVDF at high concentrations resulted in membranes with small pore sizes. PVP affected the pore size and should be used to a limited extent to avoid possible hole formation. TiO2 contents were responsible for the decolorization of a methyl orange solution (10−5 M) up to 90% over the period studied (30 h). A higher content of TiO2 did not increase the decolorization rate. Acidic conditions increased the photocatalytic activity of the TiO2-membranes.

Improvement of Properties and Performances of Polyethersulfone Ultrafiltration Membrane by Blending with Bio-Based Dragonbloodin Resin

Polyethersulfone (PES) is the most commonly used polymer for membrane ultrafiltration because of its superior properties. However, it is hydrophobic, as such susceptible to fouling and low permeation rate. This study proposes a novel bio-based additive of dragonbloodin resin (DBR) for improving the properties and performance of PES-based membranes. Four flat sheet membranes were prepared by varying the concentration of DBR (0–3%) in the dope solutions using the phase inversion method. After fabrication, the membranes were thoroughly characterized and were tested for filtration of humic acid solution to investigate the effect of DBR loading. Results showed that the hydrophilicity, porosity, and water uptake increased along with the DBR loadings. The presence of DBR in the dope solution fastened the phase inversion, leading to a more porous microstructure, resulted in membranes with higher number and larger pore sizes. Those properties led to more superior hydraulic performances. The PES membranes loaded with DBR reached a clean water flux of 246.79 L/(m2·h), 25-folds higher than the pristine PES membrane at a loading of 3%. The flux of humic acid solution reached 154.5 ± 6.6 L/(m2·h), 30-folds higher than the pristine PES membrane with a slight decrease in rejection (71% vs. 60%). Moreover, DBR loaded membranes (2% and 3%) showed an almost complete flux recovery ratio over five cleaning cycles, demonstrating their excellent antifouling property. The hydraulic performance could possibly be enhanced by leaching the entrapped DBR to create more voids and pores for water permeation.

Study of the stability of lipid nanoemulsions with oleic acid

This work presents the results of a study on the effect of ionic surfactant cetriltrimethylammonium chloride (CTAB) on the size and ζ-potential of lipid nanoemulsions composed of oleic acid, prepared by temperature phase inversion method and stabilized by nonionic surfactants — Tween 60, Span 60

A REVIEW ON VARIOUS FORMULATION OF NANOEMULSIONS IN COSMETICS WITH PLANT EXTRACTS AS THE ACTIVE INGREDIENTS

This review conducted to compare the difference of the formulation of nanoemulsion cosmetics by plant extracts between Centella asiatica, seed oil from Rubus idaeus, Phyllanthus urinaria, Garcinia mangostana L., Vellozia sauamata, and Cordyceps militaris extract. Materials and methods was taken from several literature in valid databases that focuses on current status of the formulation of nanoemulsion and its characteristics, nanoemulsion cosmetics, and formulation of nanoemulsion cosmetics that are made by plant extract as the active ingredient. Comparison of the formulas above can be seen from various aspects. Referring to each article, 4 out of 6 formulas use high energy techniques and the rest use low energy techniques. Formula 1, 3, 6 use high energy technique with high pressure homogenization, and formula 4 uses ultrasonication, which is still a high energy technique. Formulas 2 and 5 use low energy techniques, namely formula 2 using Phase Inversion Composition (PIC) and formula 5 using Phase Inversion Temperature (PIT). High-Pressure Homogenizer (HPH) is the most widely used for the manufacture of nanoemulsions. In terms of formula, the use of components such as surfactant, cosurfactant, oil phase, and water phase is also different from the 6 formulas presented. Even though all of the six formulas are different, the active ingredients in the form of nanoemulsions need to be tested until finally the goal of the cosmetic product is achieved.

Encapsulation of agrichemicals by renewable cellulosic derivatives

<p>Cellulose derivatives, charged with fungicides, have been prepared as particles for use as a wood preservative. The particles were designed to encapsulate the current industry-standard chemical agents used to minimise wood degrading fungal action and to deter termites. A detailed study on the most effective methodology that would be suitable for scaled-up production was undertaken. The methods explored included: double emulsions, solvent diffusion by dialysis membrane and phase inversion emulsification. Particles formed by these methods were characterised by scanning electron microscopy, dynamic light scattering, nuclear magnetic resonance spectroscopy and infrared spectroscopy. The fungicide incorporation was confirmed by nuclear magnetic resonance studies and gas-chromatography analytical analysis. The phase inversion emulsion process was found to be highly effective and readily manipulated to modify particle formation. Particles were successfully prepared containing fungicides in a yield of 35-75% (method dependant), containing the biocide at approximately 50% mass of biocide to total particle mass. Thus, this process was optimised through modifying the addition time of the aqueous phase, as well as variation of the surfactant and salt concentrations. With an optimised particle forming method, three fungicides were incorporated into the formulation and subsequently analysed to demonstrate successful biocide incorporation. The biocide charged mesoparticles underwent testing for antifungal action by our industrial partners Lonza.</p>