Emulsion Thickness Research Articles

Design methodology for multi-parallel pipe separator (MPPS)

The Multiple Parallel Pipe Separator (MPPS) is a design for bulk oil-water separation that utilizes multiple horizontal pipe segments connected in parallel. Drainage of water is performed through tapping points on the pipe’s bottom. Pipe segments can be added in series (stacked) if needed. The aim of this study is to develop a design methodology for the MPPS that can be adapted to varying flow conditions.The methodology employs different types of models: flow pattern, drainage potential curves, and oil-water dispersion in pipe. The flow pattern model is used to determine the number of branches and pipe diameter to ensure segregated flow patterns. The batch dispersion-separation model is used to predict the thickness of the water oil and dispersion layers approaching the tapping point. The drainage potential model is used to determine tapping point separation performance and the number of required tapping points. All models are validated with experimental data available from previous and current experimental campaigns with inlet water cut, WCinlet, from 30 % to 90 % and total flow rate from 300 to 700 L/min.The results indicate that when the flow is oil-continuous (e.g., with an WCinlet, of 30 %) and the mixture velocity is high (e.g., 0.33 m/s), the droplet coalescence is limited, and the change of the emulsion layer thickness is less than 14 % of initial emulsion thickness. However, if the number of parallel branches is increased, the mixture velocity decreases, and consequently the residence time becomes longer enough to facilitate dissolving the emulsion layer. Furthermore, when the inlet water cut is low (e.g., 30 %), increasing the number of tapping points assists in extracting the water phase with a higher water cut. Conversely, when the inlet water cut is higher (e.g., 60 %), achieving a moderate water cut requires fewer tapping points.

Drying kinetics modeling of hot air drying of emulsion templated oleogels employing hydroxypropyl methylcellulose as structuring agent

This work focused on the drying of O/W emulsions employed to obtain templated structured oils with hydroxypropyl methylcellulose (HPMC) as oleogelator. Sunflower oil/water emulsions with different HPMC content (1%–3% w/w) were dried at different air temperatures (from 70 to 100 °C) employing two different initial thicknesses (0.25 and 0.50 cm). Drying kinetics showed the existence of an initial constant drying rate period followed by a falling drying rate period below critical moisture content. This critical content was constant (0.38 kg water/kg dry solid) independently of drying conditions and HPMC content. Drying rate decreased linearly with moisture content during the falling rate periods. A 3-parameter model was proposed to simulate drying kinetics in the range of drying temperature and HPMC content of tested oleogels. Physical properties of fresh and stored (20 days) oleogels such as oil binding capacity, color, and hardness were measured to evaluate drying conditions effect on product quality. Temperatures above 70 °C were necessary to promote the HPMC gelation. Best characteristics of oleogels in terms of texture, color and oil binding capacity were obtained with HPMC content of 2% w/w, 0.25 cm of emulsion thickness and 80 °C of drying temperature. These results are useful for the design of large-scale dryers for this new kind of products.

Steady-state analysis of the 1970 Windscale nuclear criticality incident

This paper presents several steady-state neutron transport models which are used to determine the behaviour of the nuclear criticality incident that occurred at the Windscale Works in 1970. The transfer vessel involved in this incident contained two immiscible fissile liquids (an aqueous phase and an organic phase) which had been disturbed such that an emulsion layer formed between them. Infinite domains of the aqueous, organic, and emulsion phases were modelled to enable the understanding of the effects of nuclear data library, neutron transport code and material on the calculated kinetics data, effective multiplication factor and macroscopic neutron cross sections. Six possible configurations of the 1970 Windscale criticality incident were simulated using three-dimensional models in MCNP, two-dimensional models in academic research code EVENT, and one-dimensional models in a collision probability (CP) code. Quantities of interest, such as reactivity, scalar neutron flux, neutron absorption and production rates, and kinetics data are presented. System reactivity, mean neutron generation time and neutron absorption and production rates are shown to increase with increasing emulsion thickness, whereas the total scalar neutron flux is shown to decrease. It is determined that the volume of organic phase present during the transient was likely to be around 39.0 L, as the emulsion thickness required to reach criticality (6.5 cm) was within the range cited in the literature. EVENT and the CP code showed deficiencies when calculating the scalar neutron flux through the plenum gas at the top of the transfer vessel, with the CP code overestimating the total scalar neutron flux in the system by as much as 19 %. The intrinsic neutron source, subcritical multiplication and subcritical power of the system were computed using Monte Carlo simulations. It was shown, by use of the Hansen criteria, that the subcritical system was likely to be in a strong neutron source regime (such that stochastic variations in neutron population are negligible when regarding nuclear criticality transients). In addition, it was computed that a vessel containing 39.0 L of organic solvent had a subcritical power of 10.81 ±0.03μW.

Polarized radiative transfer in seawater-in-oil emulsions floated on seawater considering the impact of oil absorption on seawater droplet scattering.

Among various remote sensing approaches, optical polarization remote sensing shows great advantages in identifying oil-water emulsions in seawater and has become one of the most promising detection technologies. Herein, we focus on exploring the sensitivity of polarized radiative transfer properties for oil emulsion polarization detection to the influence factors of viewing angle, droplet volume fraction and radius, incident wavelength, and emulsion thickness. The radiative properties of seawater droplets dispersed in crude oil are calculated using the improved Lorenz-Mie theory considering the absorption of crude oil as the host medium, after which the reflected Stokes vector and the degree of linear polarization (DOLP) of seawater-in-oil emulsions floating on seawater are obtained using the spectral element method. By analyzing the calculation results of a 0° viewing azimuth angle, the detection wavelength and viewing zenith angles corresponding to the highest sensitivity of the DOLP to the above factors are significantly different; thus, quantitative remote sensing detection of the droplet volume fraction, droplet diameter, and emulsion thickness is possible. Exploring the sensitivity of polarized remote sensing signals for oil emulsion polarization detection to the above factors is a prerequisite for quantitative polarization detection of oil emulsions.

스크린 제판의 표준화에 관한 연구 - 이형지를 중심으로 한 인쇄시 -

In this study, we attempt to standardize each process in screen printing. Everything cannot be standardized based on the device and material of screen printing in an experimental environment (temperature: 23–25°C and humidity: 50–60%). The purpose of the experiment is to determine the data for each variable and obtain an optimal print through stabilization according to the screen mesh strap and exposure amount according to the thickness of the photosensitive emulsion. Screen printing is considerably difficult to standardize owing to the wide variety of substrates used. In this study, the release paper that is closest to the most widely used synthetic resin was used as the print.

INFLUENCE OF THE PROPERTIES OF THE MATERIAL OBTAINEDBY COLD MILLING OF NON-RIGID PAVEMENTS ON THE DEFORMATIONOF THE LAYER DURING THE CONSTRUCTION OF THE PAVEMENT

Statement n of the problem. Establish the effect of the size of material fractions, thickness and percentage of bitumen emulsion obtained by milling non-rigid pavements on the deformation of the layer during pavement construction.Results. It has been experimentally proven that there is a correlation between the density, strength and deformation of the layer under the action of a sealing load. The material obtained by cold milling of old non-rigid coatings has its own characteristics that must be taken into account when using it. The introduction of a binder into asphalt granulate affects not only the properties of the asphalt-granular concrete mixture, but also the formation of the structure of the pavement layer. Conclusion. Dependencies for calculating the deformation of the pavement layer have been obtained, which make it possible to predict the strength characteristics of the layer by deformation at different sizes of material fractions, layer thickness and percentage of bitumen emulsion in the mixture under the existing load during the compaction process.

Providing interlayer adhesion of dissimilar layers of top road surfaces

The article reviews the option of how to make the top pavement of asphalt-concrete mixture adhere reliably to the base, which is the underlying cement-concrete coating. The bitumen-latex emulsion is suggested as a binder for the two pavement layers. The research aimed to determine the optimal layer thickness of the bituminous-latex emulsion to be applied and achieve the maximum interlayer adhesion between the top asphalt-concrete pavement and the cement-concrete base. After full-scale experiments, the required layer thickness of the bitumen-latex emulsion was 2 mm. With this layer thickness of the binder, road pavement layers do not delaminate and shear when stressed by the intensive flows of vehicles moving on the roads. The results obtained are important for the road construction industry for suggesting the formulation of bitumen-latex emulsion and finding the most effective layer thickness to be applied. The suggested formulation of a bitumen-latex emulsion is frost-resistant. The article describes the experimental steps for determining the optimal application thickness at a fair length. The maintenance-free life of roads with an asphalt-concrete mixture on a cement-concrete base interlayered with a bitumen-latex emulsion as a binder is assumed to get much longer.

Laboratory Study of the Effect of Salinity on the Demulsification Process in High Temperature Crude Oil

In the process of drilling and servicing oil wells, KCl and NaCl used to provide hydrostatic pressure into the bowels of the earth. The brine solution was produced accidentally to the surface facility when the oil lifting process was carried out and induces the thickness of the oil-water emulsion in the separation tank. Emulsions must be broken down into oil and water phases so that they do not interact with the oil treatment process in the refinery unit. Emulsion stability was influenced by pH, salinity, temperature and concentration of asphaltene, resin and wax. The purpose of this study was to determine the effect of salinity on the oil-water demulsification process. This research was conducted by varying the salinity of 5%, 15%, 25%, and 35% in a 100 ml oil-water emulsion sample with a ratio of 1: 1 oil and water. Demulsification of the emulsion sample using the precipitation method for 120 minutes by recording the% of oil volume separate every 20 minutes, at temperatures of 30 ° C and 110 ° C. The higher the temperature given, the more stable the emulsion in crude oil. From the final result after 120 minutes of pricipitation shows that the emulsion separation process which influenced by NaCl salinity is more difficult than the effect of KCl salinity.

Graphitic Carbon Nitride Stabilizers Meet Microfluidics: From Stable Emulsions to Photoinduced Synthesis of Hollow Polymer Spheres.

Graphitic carbon nitride (g-CN) has been utilized as a heterogeneous catalyst, but is usually not very well dispersible. The amphiphilic character of g-CN can be altered by surface modifications of g-CN nanopowders. Introducing hydrophilicity or hydrophobicity is a promising avenue for producing advanced emulsion systems. In this study, a special surface-modified g-CN is used to form stable Pickering emulsions. Using a PDMS-based microfluidic device designed for stable production of both single and double emulsions, it is shown that surface-modified g-CNs allow the manufacture of unconventionally stable and precise Pickering emulsions. Shell thickness of the double emulsions is varied to emphasize the robustness of the device and also to demonstrate the extraordinary stabilization brought by the surface-modified carbon nitride used in this study. Due to the electrostatic stabilization also in the oil phase, double emulsions are centered. Finally, when produced from polymerizable styrene, hollow polymer microparticles are formed with precise and tunable sizes, where g-CN is utilized as the only stabilizer and photoinitiator.

Recording Ultra-Realistic Full-Color Analog Holograms for Use in a Moving Hologram Display.

This paper demonstrates a method to record a set of twelve ultra-realistic full-color analog holograms presenting the same brightness, transparency and homogeneous colors for the fabrication of a Fantatrope, a dynamic holographic 3D display, without the need for special viewing aids. The method involves the use of 3D printer technology, a single-beam full-color Denisyuk optical setup with three low-power lasers (red, green, and blue) and an iso-panchromatic high-sensitive silver-halide holographic emulsion specially designed for recording analog holograms without any diffusion. A cyclic animation is created with a 3D computer graphics program and different elements are 3D printed to form models for the holograms. Holograms are recorded with a full-color holographic setup and developed using two simple chemical baths. To prevent any emulsion thickness variations, the holograms are sealed with optical glue. Results confirm that all holograms recorded with this protocol present the same characteristics, which allow them to be used in the Fantatrope.

Impact of process parameters on printing resolution and dielectric properties of LTCC substrate

Purpose The low-temperature co-fired ceramics (LTCC) microfluidic-microwave devices fabrication requires careful consideration of two main factors: the accuracy of deposition of conductive paths and the modification needed to the standard process of the LTCC technology. Neither of them are well-described in the literature. Design/methodology/approach The first part of this paper deals with the individual impact of screen parameters such as aperture, photosensitive emulsion thickness and mounting angle on the precision of the screen-printed conductive paths fabrication. For the quantitative analysis purposes, the design of experiment method with Taguchi orthogonal array and analysis of variance was used. The second part contains the characterization of the complex permittivity measured for different values of LTCC substrates lamination pressure. Findings It can be concluded, that the combination of aperture, equal to 24 µm, emulsion thickness 20 µm and mounting angle 22.5° ensures the highest quality of printed conductive metallization. Furthermore, the obtained results indicate, that the modification of the lamination pressure does not affect significantly the dielectric parameters of the LTCC substrates. Originality/value This paper shows two aspects of the fabrication of the microfluidic-microwave LTCC devices. First, the resolution of the applied metallization is critical in manufacturing high-frequency structures. The obtained experimental results have shown that optimal screen parameters, in terms of conductive pattern quality, can be found. Second, the received outcomes indicate that the changes in the lamination pressure do not affect significantly the electrical parameters of the substrate. Hence, this effect does not need to be taken into account.

Numerical simulation of double emulsion formation in cross-junctional flow-focusing microfluidic device using Lattice Boltzmann method

This paper presents an analysis of double emulsion formation through a cross junctional flow-focusing microchannel which uses an improved color gradient lattice Boltzmann method. The model with the potential to simulate a ternary system of immiscible fluids was employed. Two double emulsion formation regimes, one-step and two-step, were simulated. The effect of the inner flow rate, as well as inner and outer flow viscosity was investigated on double emulsion formation. The inner flow rate had a significant influence on the inner liquid jet detachment point in the two-step process. However, the viscosity of the inner and outer fluid considerably affected the double jet detachment point in the one-step formation. The shell thickness of a double emulsion can be adjusted by altering the inner flow rate.

Screen Printing Fine Pitch Stretchable Silver Inks onto a Flexible Substrate for Wearable Applications

Abstract This article presents the development and optimization of the screen printing process for printing stretchable silver ink onto a stretchable thermoplastic polyurethane substrate. A test vehicle was designed including 50 μm/5 mm (line width/line length) to 350 μm/35 mm lines (at four biases). A two-level factorial design with three replicates was selected to investigate the effect of process parameters on the quality of prints. We proposed calculated sheet resistance based on the measured resistance value, trace width, and trace length, which can replace trace height measurements on rough profile substrates. We found that squeegee pressure and emulsion thickness have statistically significant effects on calculated sheet resistance of print traces, whereas print speed does not have statistically significant effects. In our experiment setting levels, the lower the squeegee pressure, the lower the calculated sheet resistance that is achieved. The emulsion with higher emulsion over mesh (EOM) is better than the emulsion with lower EOM because it can achieve lower sheet resistance. After optimizing the screen printing process, we were able to print 100 μm (4 mils) trace width and spacing with high consistency.

Screen Printing Fine Pitch Stretchable Silver Inks onto a Flexible Substrate for Wearable Applications

Abstract The lightweight and bendable features of printed flexible electronics are increasingly attractive. Currently stretchable silver inks are formulated for wide traces, typically larger than 2 mm. To attach ultra-thin silicon chips that have fine pitch onto printed organic substrate, it is necessary to print fine trace width/space that matches the pitch of the chips, which may be less than 200 microns. This paper presents the development and optimization of the screen printing process for printing stretchable silver ink onto stretchable thermoplastic polyurethane (TPU) substrate. A test vehicle was designed including 50 μm/5 mm (line width/line length) to 350 μm/35 mm lines (at 4 biases). The stretchable ink selected was DuPont PE 873 and Dupont's PE 5025 ink (non-stretchable conductive flake silver) was used as a “control” to baseline the printing process. The substrate used was Bemis TPU ST604. The experiment was done on a DEK Horizon 03i printer. A DEK squeegee 200 (Blue) and a DEK 265 flood bar (200 mm) were used. A 2-level factorial design with three replicates was selected to investigate the effect of process parameters on the quality of prints. The quality of the prints is characterized by 1) resistance of traces, 2) sheet resistance, 3) z-axis height, and 4) trace width/spacing. We observed significant noise in the z-axis printed silver ink height measured by profilometry and concluded z-axis height is not a good response variable for characterizing screen printing stretchable silver ink onto TPU substrate, mainly due to high roughness of the TPU substrate. We proposed calculated sheet resistance based on the measured resistance value, trace width, and trace length, which can replace trace height measurements on rough profile substrates. We found that squeegee pressure and emulsion thickness have statistically significant effects on calculated sheet resistance of print traces while print speed does not have statistically significant effects. In our experiment setting levels, the lower the squeegee pressure, the lower the calculated sheet resistance that is achieved. The emulsion with higher emulsion over mesh (EOM) is better than the emulsion with lower EOM since it can achieve lower sheet resistance. After optimizing the screen printing process, we were able to print 100 μm (4 mils) trace width and spacing with high consistency.

Scalable production of double emulsion drops with thin shells.

Double emulsions are often used as containers to perform high throughput screening assays and as templates for capsules. These applications require double emulsions to be mechanically stable such that they do not coalesce during processing and storage. A possibility to increase their stability is to reduce the thickness of their shells to sufficiently low values that lubrication effects hinder coalescence. However, the controlled fabrication of double emulsions with such thin shells is difficult. Here, we introduce a new microfluidic device, the aspiration device, that reduces the shell thickness of double emulsions down to 240 nm at a high throughput; thereby, the shell volume is reduced by up to 95%. The shell thickness of the resulting double emulsions depends on the pressure profile in the device and hence on the fluid flow rates in the channels and is independent of the shell thickness of the injected double emulsions. Therefore, this device enables converting double emulsions with polydisperse shell thicknesses into double emulsions with well-defined, uniform thin shells.

The distribution of oil film on work piece and rollers in cold rolling using O/W emulsions

Abstract Oil film plays a key role in lubrication. However, the distribution of oil film on work piece and rollers is not clear. In order to explore the regularities of distribution on oil film, cold rolling experiments were conducted by Ф400/170 × 300mm 4-high millers. Ellipsometry measurement was used to measure oil film thickness. The results show that 60 percent of oil deposits on work piece and the rest 40 percent remains on the rollers, which differs from the equal distribution assumption that is usually thought. Furthermore, parameters which can affect oil film thickness were analyzed. The relationships among oil film thickness and concentrations of emulsion, viscosity of emulsion and maximum rolling pressure were investigated. The results have certain guiding significance to the choice of lubricating parameters and the determination of lubrication state.

High pressure pre-treatment of Moringa oleifera seed kernels prior to aqueous enzymatic oil extraction

Abstract High pressure processing (HPP) was applied as a pre-treatment on Moringa oleifera (MO) kernels, for the first time, prior to aqueous enzymatic extraction (AEE) of the MO oil, and the effect of this pre-treatment is reported in terms of the free oil recovery and the nature of the cream emulsions formed. The HPP pre-treatments (50–250 MPa, 20–60 °C, 10–60 min) generally resulted in higher free oil recoveries and thinner emulsion layers from ground-sieved kernels than the whole kernels. Optimization of the HPP parameters indicated linear increment in free oil recovery with increase in temperature and time, but not the pressure level. Without the pre-boiling step in the AEE process, the use of HPP pre-treatment at 50 MPa and 60 °C for 35 min resulted in approximately 73% (w/w) free oil recovery with thinner emulsion layer than the use of AEE alone. These findings highlighted the ability of HPP in altering the MO protein structure into a form of less emulsifying functional properties, thus further de-emulsification method may not be necessary. Industrial relevance High pressure processing (HPP) applications are increasing in the food industry. High pressure application allows the use of relatively lower temperatures in processes, in order to achieve comparable outcomes of higher temperature processing. This study explores the application of HPP on Moringa oleifera (MO) kernels prior to aqueous enzymatic extraction (AEE) of oil. In general, the main disadvantage of AEE is its lower oil recovery in comparison with solvent extraction, which is attributed to the formation of a relatively stable cream emulsion after extraction. This study shows that the thickness of the creamy emulsion can be significantly reduced, and oil recoveries improved, by subjecting the kernels to HPP prior to extraction. The improvement in recoveries did not depend strongly on the level of high pressure applied, but downstream processes for free oil separation and recovery were considerably simplified.

Reducing the shell thickness of double emulsions using microfluidics

Double emulsion drops are well-suited templates to produce capsules whose dimensions can be conveniently tuned by adjusting those of the drops. To closely control the release kinetics of encapsulants, the composition and thickness of the capsule shell must be precisely tuned; this is greatly facilitated if the shell is homogeneous in its composition and thickness. However, the densities of the two drops that form the double emulsion are often different, resulting in an offset of the two drop centers and therefore in an inhomogeneous shell thickness. This difficulty can be overcome if the shell is made very thin. Unfortunately, a controlled fabrication of double emulsions with thin shells is difficult. In this paper, we present a microfluidic squeezing device that removes up to 93 vol% of the oil from the shell of water–oil–water double emulsions. This is achieved by strongly deforming drops; this deformation increases their interfacial energy to sufficiently high values to make splitting of double emulsions into double emulsions with a much thinner shell and a single emulsion oil drop energetically favorable. Therefore, we can reduce the shell thickness of the double emulsion down to 330 nm. Because this method does not rely on solvent evaporation, any type of oil can be removed. Therefore, it constitutes a new way to produce double emulsions with very thin shells that can be converted into thin-shell capsules made of a broad range of materials.

Gafchromic EBT3 film dosimetry in electron beams - energy dependence and improved film read-out.

For megavoltage photon radiation, the fundamental dosimetry characteristics of Gafchromic EBT3 film were determined in 60Co gamma ray beam with addition of experimental and Monte Carlo (MC)‐simulated energy dependence of the film for 6 MV photon beam and 6 MeV, 9 MeV, 12 MeV, and 16 MeV electron beams in water phantom. For the film read‐out, two phase correction of scanner sensitivity was applied: a matrix correction for scanning area and dose‐dependent correction by iterative procedure. With these corrections, the uniformity of response can be improved to be within ±50 pixel values (PVs). To improve the read‐out accuracy, a procedure with flipped film orientations was established. With the method, scanner uniformity can be improved further and dust particles, scratches and/or dirt on scanner glass can be detected and eliminated. Responses from red and green channels were averaged for read‐out, which decreased the effect of noise present in values from separate channels. Since the signal level with the blue channel is considerably lower than with other channels, the signal variation due to different perturbation effects increases the noise level so that the blue channel is not recommended to be used for dose determination. However, the blue channel can be used for the detection of emulsion thickness variations for film quality evaluations with unexposed films. With electron beams ranging from 6 MeV to 16 MeV and at reference measurement conditions in water, the energy dependence of the EBT3 film is uniform within 0.5%, with uncertainties close to 1.6% (k=2). Including 6 MV photon beam and the electron beams mentioned, the energy dependence is within 1.1%. No notable differences were found between the experimental and MC‐simulated responses, indicating negligible change in intrinsic energy dependence of the EBT3 film for 6 MV photon beam and 6 MeV–16 MeV electron beams. Based on the dosimetric characteristics of the EBT3 film, the read‐out procedure established, the nearly uniform energy dependence found and the estimated uncertainties, the EBT3 film was concluded to be a suitable 2D dosimeter for measuring electron or mixed photon/electron dose distributions in water phantom. Uncertainties of 3.7% (k=2) for absolute and 2.3% (k=2) for relative dose were estimated.PACS numbers: 87.53.Bn, 87.55.K‐, 87.55.Qr

Investigation into heat transfer and fluid flow characteristics of liquid two-layer and emulsion in microwave processing

Numerical study of fluid flow and heat transfer within two types of liquid (liquid two-layer and oil–water emulsion) when subjected to microwave energy are discussed. In order to obtain the simulation of microwave heating from room temperature, a 2D comprehensive model was integrated with electromagnetic field, incompressible laminar flow and heat transfer. The effects of layered configuration, layered thickness and dispersed fraction of emulsions were investigated. Temporal profiles obtained using fiber optic sensors at four discrete points were compared with the simulated temperature profiles. The simulated outlet temperatures of liquid had a good agreement with experimental data within the maximum prediction error of 5%. The theory presented in this paper can be effectively used to explain fluid transport during microwave heating system using the rectangular waveguide.