Average Droplet Diameter Research Articles

Effect of impinging angles of liquid–liquid distributor on the extraction and mass transfer performance in a rotating packed bed

Liquid-liquid extraction is a typical separation process that is widely used in various chemical processes. However, the effect of two-liquid feeding mode on the liquid–liquid Murphree efficiency (E) of rotating packed bed (RPB) remains unclear, limiting its applications. In this work, liquid–liquid distributor with different impinging angles (2θ) of two feeding liquid jets in the RPB was designed to evaluate the E, taking water as the extractant to extract benzoic acid from kerosene into the aqueous phase. The effects of operating conditions such as the 2θ, high gravity level (β), and liquid initial velocity (u0) on the E and overall volumetric mass transfer coefficient (KLa) of the RPB were studied. Experimental results revealed that both E and KLa increased with the increase of 2θ, β, and u0. In particular, when 2θ = 90°, E and KLa exhibit optimal values. At β = 49.25, u0 = 1.75 m/s, and 2θ = 90°, since the average diameter of the daughter droplets was smaller and the effective mass transfer area was larger, E reached a maximum of 64.7 % and KLa was 0.489 s−1. A correlation for predicting KLa has been established, with deviations falling within ± 20 %. This work provides theoretical basis for guiding the enhancement of mass transfer in liquid–liquid systems.

Novel bigel based on nanocellulose hydrogel and monoglyceride oleogel: Preparation, characteristics and application as fat substitute

In the present study, bigels containing nanocellulose hydrogel and monoglyceride oleogel were prepared as a novel fat substitute. The nanocellulose was derived from chestnut shells via TEMPO oxidation, resulting a yield of 59.6 %. The impact of varying the oleogel/hydrogel ratio on the macroscopic and microscopic structures, chemical interactions, and the textural, thermal and rheological properties of the bigels was explored. As the hydrogel content increased from 20 % to 50 %, the average droplet diameter in the bigels increased. The bigels transitioned from a water-in-oil structure to a bi-continuous structure, and the textural hardness, cohesiveness, and rheological properties improved significantly. Shortbread cookies were prepared by incorporating different proportions of the bigels to replace animal butter as shortening, and the color, spreadability, hardness and baking loss rate of cookies were analyzed. The result showed that replacing butter with bigels in cookie preparation could reduce fat content without significantly altering the appearance or properties of the cookies. These prepared bigel have the potential to serve as a healthy and sustainable solid fat substitute in the food industry.

Investigation of airflow thermal ice melting process under various flight conditions

The challenge of preventing and removing ice from exposed regions of aircraft is a significant engineering concern. Understanding the melting process of ice due to aerodynamic heating during flight is essential for developing UAV flight strategies in icy conditions. This paper analyzes the heat transfer mechanisms involved in airflow over ice and introduces a theoretical model to estimate the ice melting rate, using principles of turbulent heat transfer at the stagnation point. The study also discusses the impact of environmental conditions on ice melting rates. Findings indicate that the melting speed of the ice surface exhibits a negative linear correlation with the initial temperature of the ice, whereas it shows a nonlinear correlation with airflow velocity and total temperature of the incoming flow. Lower airflow velocity or total temperature of the incoming flow enhances the sensitivity of ice melting speed to changes. Additionally, lower ice density results in a higher melting speed, showing an exponential relationship with factors like average droplet diameter, airflow velocity, and airfoil leading edge diameter in the cloud field during icing. Experiments conducted using a small jet test bench and an icing wind tunnel confirmed the impact of varying conditions on ice melting rates. The deviation between experimental results and theoretical predictions was under 5 %. These conclusions offer valuable insights for flight safety planning of unprotected iced aircraft in challenging environments.

Edge-affected droplet dynamic and subsequent frost growth characteristics for horizontal cold plate under different humidity levels

Frosting widely exists in engineering applications and mostly has negative impacts. To better avoid or utilize frosting, more micro and systematic investigations into the frosting mechanisms are necessary. In this study, the combined effect of humidity and plate edge on droplet dynamic and the subsequent frost growth characteristics of a horizontal cold plate is experimentally investigated. The results show that the difference in the durations of droplet condensation stage between edge-affected and unaffected regions is little, and both decrease from around 480 to 43 s when relative humidity (RH) increases from 30% to 80%. In contrast, the difference in the durations of droplet freezing stage between edge-affected and unaffected regions is significant. The former is around 9 s at all humidity levels, while the latter decreases from around 100 s to 40 s when RH increases from 30% to 80%. Meanwhile, the average equivalent droplet diameters in the edge-affected region are 87.3 × 10−3–122.1 × 10−3 mm, which are 31.0 × 10−3–45.5 × 10−3 mm larger than in the unaffected region. The frost layer surface roughness at 80% RH is smaller than others due to the frost crystal reverse melting. This paper can help better understand the frosting mechanism from a microscopic scale and guide the accurate prediction of frost formation.

Dynamic behavior regulation of droplet transfer based on arc-bubble control by ultrasound-induced during underwater wet welding

In comparison to welding in air, the periodic formation of unstable arc bubbles is a significant factor contributing to the unstable mass transfer process during underwater wet welding (UWW). Up to now, there is no ideal method to control droplet transfer and improve arc stability. In this study, the ultrasound-induced method (UIM) was used to regulate the droplet transition behavior and improve the process stability. The behavior features and key mechanisms of arc-bubble and droplet transfer induced by ultrasound were revealed with the employment of highspeed camera and X-ray observation, respectively. The incident angle of ultrasound was taken as a variable to reveal its effects and mechanism of action on the behaviors of arc bubble and droplet transfer, weld formation quality, microstructure, and property of weld joint. The results show that ultrasound-induced a new rising mode of arc bubble, which can significantly reduce the repulsive resistance that come from the bubble rising on the droplet transfer process. Compared with underwater wet welding without ultrasound, the average diameter of molten droplets reduces from 3.2 mm to 1.7 mm, and the droplet transfer frequency increases from 7.8 Hz to 13 Hz as the incident angle of ultrasound increases to 60°. In addition, the weld seam without obvious defects could be produced by UWW with UIM, of which the Variation coefficient of weld reinforcement is reduced from 21.3 to 11.6 and 17.4 at an ultrasonic incident angle of 30° and 45°. With increasing of ultrasound incident angle, it showed that the microhardness of the weld joint has a slight increase. In the heat-affected zone, the microhardness for the joint increased from 290 HV to 320 HV while the incident angle increased to 60°. This research shows that an appropriate incident angle of ultrasound can obtain good-quality joints which has a stable metal transfer process in underwater wet welding.

ПРИМЕНЯЕМОСТЬ ВОДОГАЗОВЫХ ФОРСУНОК ДЛЯ ПОЖАРОТУШЕНИЯ ТОНКОРАСПЫЛЕННОЙ ВОДОЙ

The low efficiency of traditional water extinguishing systems is due to the formation of large droplets. Large droplets have a small external surface area, which causes poor heat removal from the ignition source. A large external surface area of droplets is provided by fire extinguishing systems with thinly sprayed water. They are effective in extinguishing fires at the initial stage of a fire in confined spaces and ensure the formation of droplets less than 150 microns. The analysis showed that water-gas nozzles with co-directional flows of water and gas are suitable for creating finely dispersed water with a droplet size of less than 100 microns. To ensure significant heat removal from the ignition source, the average diameter of the droplets of finely dispersed water should be less than 80 microns. A technique for determining the size of droplets when sprayed with water-gas nozzles is presented. According to the method, the calculation of the average diameter of droplets was carried out depending on the ratio of volume flow rates of gas and water. It is shown that fire extinguishing with finely sprayed water with the help of water-gas nozzles is effective at a gas pressure in front of the annular gap from 0,4 MPa to 0,6 MPa and the ratio of volumetric air flow to volumetric water flow is more than 2 000.

Application of modified corn starch in stabilization of ultrasonic-assisted pickering oil in water emulsion

Starch is a sustainable and cheap raw material claimed as a good emulsion stabilizer for edible products either in food or pharmaceutical industry. To produce an emulsion stabilized by food based edible stabilizer, this study focused on the non-chemical starch modification for oil in water (O/W) emulsion stabilization produced by ultrasonic emulsification. The results showed that the finest emulsion was obtained at power rate of 500 W for 7 mins of sonication. The stability of the emulsion was investigated by turbidity, centrifugal stability values and droplet size. Pre-gelatinized corn starch (PCS) stabilizer showed better emulsion stability compared to gelatinized corn starch (GCS) due to the different polysaccharide components of the two modified cornstarch. GCS mainly contained amylose while the PCS contained both amylose and amylopectin. The emulsion, stabilized by 6 wt.% of PCS and addition of 3 wt.% of tween-80 exhibited excellent storage stability, along the 30 days storage. The results showed the lowest turbidity of 1.01 cm-1 , centrifugal stability value of 36.85% and average droplet diameter of 14.27 µm.

Experimental study on the film droplet production from a bubble burst on the free surface

The aerosol released during a severe reactor accident may be retained in the liquid pool. During the venting stage of the suppression pool, bubbles generated in the pool will rise to the free surface and burst to generate droplets. The airflow re-entrains aerosols from the liquid to the air via droplets. Accurate evaluation of droplet entrainment needs to acquire the diameter and number of droplets generated by a bubble, so studying the various behaviors that affect the above parameters is necessary. In this paper, high-speed photography is used to visualize the phenomenon of a single bubble burst to generate film droplets in deionized water and TiO2 suspensions at different phase temperatures. Image processing is used to obtain the bubble film opening rate, the bubble burst position, the bubble lifetime, and the diameter and number of film droplets. The results show that the film thickness decays with time in a power law with a parameter of 2/3, and the newly defined film thickness also decays with time in a power law after considering the bubble radius and physical parameters. This rule is applicable in different liquid temperatures and solutes. Besides, the film thickness increases with liquid temperature and aerosol concentration; the bubble lifetime obeys the Weibull distribution, with the average bubble lifetime of deionized water varies non-monotonically with the liquid temperature, the average lifetime increase with aerosol concentration and liquid temperature in aerosol suspension; The average droplet diameter decreases with bubble lifetime in a power law with a parameter of 5/16, the droplet diameter distribution can be calculated by the gamma distribution of the normalized droplet diameter and the bubble lifetime, and in good agreement with the experimental data, the droplet entrainment factor can also be calculated from the critical droplet diameter and bubble lifetime, which decreases with bubble lifetime.

Condensation and droplet characteristics in hydrogen recirculation ejectors for PEM fuel cell systems

The hydrogen recirculation ejector plays a pivotal role in proton exchange membrane fuel cell systems. Nevertheless, a comprehensive grasp of the intricate two-phase flow characteristics within hydrogen recirculation ejectors remains elusive. This investigation delves into the condensation and droplet behaviors of an ejector designed for a 100 kW fuel cell stack. The analysis relies on a two-phase flow model that takes into account both homogeneous and heterogeneous condensation. The findings reveal that homogeneous condensation nuclei manifest within the mixing chamber when the stack power surpasses 31 kW. The average median diameter of homogeneous droplets at the ejector outlet measures 0.367 μm, whereas that of heterogeneous droplets stands at 1.265 μm, signifying a 26.5 % augmentation compared to their initial size. Additionally, two crucial factors impact droplet size: residence time and subcooling degree. At the 100 kW condition, the droplet residence time is a mere 0.272 ms, yielding a meager droplet flow rate of merely 1.79 mg/s. In contrast, at the 53 kW condition, the downstream of the mixing chamber exhibits the maximum subcooling degree, resulting in the maximum droplet flow rate of 22.12 mg/s. A temperature elevation of 2.68 K at the ejector outlet is observed due to the latent heat of condensation. Furthermore, condensation has a marginal impact on the entrainment ratio, with the most significant reduction being 4.18 %, averaging at 1.42 %.

The Effect of High-Pressure Homogenization Conditions on the Physicochemical Properties and Stability of Designed Fluconazole-Loaded Ocular Nanoemulsions.

The growing interest in high-energy emulsification is a result of its scalability, which is important from an industrial perspective and allows for a more reproducible and efficient production of pharmaceutical formulations. The aim of this study was to evaluate the effect of composition, mainly a fixed surfactant/cosurfactant (Smix) ratio, their concentration, and the parameters of high-pressure homogenization (HPH) processing on the quality and stability of ophthalmic fluconazole-loaded nanoemulsions. After a physicochemical analysis of nanoemulsions containing 20% w/w of oil, as optimal conditions for the HPH process, three cycles at a pressure of 1000 bar were established, obtaining formulations with an average droplet diameter size in the range of 80.63-129.68 nm and PDI values below 0.25. While it was expected that an increasing cosurfactant concentration decreased the droplet size, in the case of formulations containing Tween 20 and 10% w/w of cosurfactants, "over-processing" was observed, identified by the droplet size and polydispersity index increase. Consecutively, the selected formulations were evaluated for in vitro drug release in Franz's cell, antifungal activity, and 30-day stability using NMR spectroscopy. An antifungal activity test showed no significant difference in the antifungal activity between optimal fluconazole-loaded nanoemulsions and a 0.3% aqueous drug solution, but previously, research showed that prepared formulations were characterized by a higher viscosity and satisfactory prolonged release compared to a control. In a 30-day stability study, it was observed that higher HLB values of the used surfactants decreased the stability of the formulations in the following order: Kolliphor EL, Tween 80, Tween 20. The NMR spectra confirmed that Kolliphor EL-based formulations ensured the higher stability of the nanoemulsion composition in comparison to Tween 80 and a better stabilizing effect of propylene glycol as a cosurfactant in comparison to PEG 200. Therefore, the optimization of HPH technology should be focused on the selection of Smix and the Smix:oil ratio in order to prepare stable formulations of high quality.

Study on the coupling effect of chemical color and structural color for Lushan speckle porcelain glaze in the Tang Dynasty (618-907 A.D.)

The Lushan speckle porcelain glaze with charming color fired in the Tang Dynasty (618-907A.D.), is the earliest high-temperature kiln-changed glaze. To clarify its coloring mechanism, the correlation among composition, microstructure and visual appearance of the shards excavated from Lushan kiln site was investigated by XRF, XPS, SEM and TEM. The results indicated that the coloring of sky-blue or moon-white opalescence glaze of the Lushan speckle porcelain was the combination of the chemical color of iron ions and the structural color formed by the coherent scattering of phase-separated droplets. The high atomic ratio of Fe2+/Fe3+ and the small average diameter of phase-separated droplets were beneficial for the formation of the blue opalescence with high color saturation. In addition, it was precisely the presence of black bottom-glaze that incoherent scattering light was greatly absorbed, leading to a higher contrast and a more pronounced structural color of the opalescence glaze.

A study on the model of solar radiation transfer in multi-layer glass facade with attached droplets

To obtain the optical properties of the spray cooling double skin façade (SC-DSF), a solar radiation transfer model of the multi-layer glass system with attached droplets is proposed in this study. The solar radiation is segmented into direct and diffuse radiation, and the monte carlo ray tracing method and angle discretization method are used to obtain the optical properties of the single layer glass with attached droplets. And then, the energy balance equation of the multilayer glass system is established based on the net-radiation method, and the transmittance, reflectance and absorptance of the multilayer glass system are calculated. The effectiveness of the proposed method is verified by the experimental results, which shows the numerical results are in good agreement with the experimental data. In addition, some important influence factors are analyzed and discussed, including the solar incidence angle, the droplet contact angle, the droplet coverage rate, and the average droplet diameter. It is found that there is little influence on the system transmittance when the incidence angle is smaller than 40°. However, the transmittance decreases with the increase of the incidence angle when the solar incidence angle is greater than 40°. When the droplet contact angle is small (less than 40°) or large (larger than 140°), its influence on the transmittance of the system is negligible. Subsequently, with the increase in the droplet contact angle within 40–140°, the transmittance firstly decreases and then increases. Adjusting the droplet coverage rate and droplet size is an effective measure to decrease transmittance and solar heat gain.

The effects of aerosol concentration on the evolution, transport, and deposition of hygroscopic droplets in the highly idealized MT model: A numerical study

Inhalation therapy is widely used to treat various respiratory diseases. Nebulizers have been widely adopted due to their ease of operation, high drug delivery efficiency, and low residual volume. Traditional studies on drug delivery in the respiratory tract typically use a one-way coupled method to track drug transport and deposition for non-hygroscopic drug particles. However, neglecting the concentration of nebulized hygroscopic droplet aerosols can lead to significant discrepancies in the deposition efficiency (DE) of nebulized drugs in the airways. To investigate the effect of different nebulization rates on the evolution, transport, and deposition of droplets, a highly idealized mouth-throat (MT) model was selected as a testbed for the in silico trials of drug delivery to the respiratory tract. The interaction between continuous and discrete phases was modeled using a two-way coupled model of highly concentrated droplet aerosol-water vapor interaction, innovated by the particle parcel method. The effects of different coupling methods and boundary conditions on the average droplet diameter and droplet deposition distribution pattern at the outlet of the MT model were compared using a computational fluid dynamics (CFD) method. Simulation results indicate that neglecting the effect of water vapor evaporated from the droplets on the relative humidity (RH) in the oral cavity could lead to a 2.2-fold prediction error of the average droplet diameter at the outlet of the MT model for a conventional nebulization rate of 0.386 g/min. As the nebulization rate increases, the difference in the predicted average droplet diameter at the outlet of the MT model between the one-way coupled method and the two-way coupled method also increases. Increasing the nebulization rate during inhalation therapy could lead to incomplete evaporation of drug droplets, resulting in deposition of larger diameter drug droplets in the oral cavity. In contrast, a lower nebulization rate can reduce the droplet diameter at the outlet of the MT model, allowing it to enter deeper airways.

Formation of Nigella Sativa L. seed oil nanoemulsion‐based delivery systems by sonication: Factors affecting particle size and stability

AbstractDue to their unique functional properties, nanoemulsions help enrich many hydrophobic compounds in water‐based beverages. In this study, using two nonionic surfactants (Tween 40 and Tween 80), separately, nanoemulsions containing Nigella Sativa L. oil were prepared by ultrasound method and tested to determine their size, polydispersity index, morphology, turbidity, and stability during 60 days of storage. In this study, the type of nonionic surfactants used significantly affected the average droplet diameter in the formed systems. Hence, Tween 40 produced tiny droplets, while using Tween 80 produced larger droplets. The comparison of the mean particle sizes by the Duncan method at a 95% confidence level showed that the effect of different surfactant concentrations (2, 4, 6, and 8 wt%) on the particle size was significant. The results showed that the lowest particle size corresponding to the formulation with 4 wt% Tween 40 and the 15‐min sonication was 59.2 nm, and the particle size distribution was monomodal. The results indicated that in the absence of a cosurfactant (glycerol), both pasteurization and boiling processes increased in particle size. However, adding glycerol before the thermal process improved the thermal stability of the samples. The results of this study revealed that ultrasound could be used to prepare nanoemulsions with microscopic particles in the nanometer size without high concentrations of synthetic surfactants.

Characterization of Sprays Generated by the Expansion of Emulsions with Liquid Carbon Dioxide

AbstractExpanding emulsions with liquid CO2 facilitates the creation of aerosols with an average droplet diameter in the low micrometer size range, which is challenging with conventional atomizers. The droplet formation process of the expansion of high‐pressure emulsions was investigated using a plain‐orifice atomizer and different swirl nozzles. The local droplet size and droplet velocities were measured and used to estimate the local Weber number and thus infer the droplet size reduction. Measurements of the local mass concentration in the aerosol showed that, for the swirl nozzle, the highest concentration was found outside of the central axis, indicating radial momentum generated by the swirl nozzle. Furthermore, it was shown that the type of expansion nozzle used has an influence on the resulting median droplet size in the aerosol. For a water mass load of 0.01, the median droplet diameter was reduced from 8 to 3 μm by increasing the swirl number from 0.01 to 0.1.

Effects of clove essential oil (Caryophyllus aromaticus L.) nanoemulsion incorporated edible coating on shelf-life of fresh cut apple pieces

Fresh cut fruit is ready to eat and can be taken on the go. Freshly cut apple pieces are perishable and prone to contamination that can damage its quality. In the current investigation, clove essential oil was used to formulate nanoemulsion (NE) in three distinct concentrations, NE-1 (0.1%), NE-2 (0.5%), and NE-3 (1%), which were then incorporated with Sodium Alginate (SA) based coating solution to impart their qualities to the outer surface of apple pieces. Sodium alginate layer helps to extend the shelf life of fruits by reducing moisture loss, inhibiting microbial growth, and protecting against physical damage. Physico-chemical properties of this solution were investigated using Box–Behnken design after it was employed to coat the freshly cut apple pieces and stored at 4 °C for 14 days. The clove essential oil nanoemulsion's average droplet size and Zeta Potential were in the nanometric range. The addition of increasing concentrations of clove nanoemulsion to the alginate coating solution decreased the zeta potential of the colloidal dispersion from −51.0 to −3.02 mV. The average droplet diameter of the edible coatings containing different clove nanoemulsion concentrations (81.04–3342 nm), whereas sodium alginate edible coating solution (SA) was in micrometric range. The Total phenol content and Antioxidant content of CEO based samples were found to be high as 38.9 mg/ml and 79.1% respectively because of bioactive chemicals and essential oil properties. NE-3 coated apple samples were found to more affective compared with the control and SA coated samples in terms of sensory and shelf-life metrics among all the treatments.

Development of a spray-ejector condenser for the use in a negative CO2 emission gas power plant

One promising solution for developing low-emission power technologies is using gaseous fuel combustion in pure oxygen when the exhaust gas mixture is composed of H2O and CO2, and where CO2 is separated after steam condensation. The paper presents the results of computational analyses providing to the Spray-Ejector Condenser (SEC) development, which is one of the crucial components of the negative CO2 gas power plant (nCO2PP) cycle development. The proposed design of the ejector-condenser to ensure the high effectivity of vapor condensation and CO2 compression with preparation to separation, ready for application in gas power cycle, is a novelty of this research. Different computational techniques leading to the development and better understating of ejector operation were applied. The main operating conditions in the characteristic connected with the developed nCO2pp cycle points were investigated to evaluate the impact of the operating conditions on SEC performances. The amount of motive water needed for the cooling purpose is susceptible to the inlet water pressure and temperature and strongly affects the generated pressure of the suction stream. The preliminary results confirm that the SEC's basic design and geometrical dimensions can be applied in the negative CO2 power plant cycle. Results from CFD modeling give the possibility to investigate the turbulent flow of water/steam/CO2 mixture together with the condensation process occurring at this same time. It is found that the average droplet diameter and motive water supplying method significantly effects the condensation intensity. The further direction of the presented computational research activities and results is to test various designs of Spray-Ejector Condensers that will enable the evaluation of the direct contact condensation process and develop the final geometrical design.

Are Most Micrometer Droplets (>10 μm) Wasted in Electrospray Ionization? An Insight from Real-Time High-Speed Imaging.

Electrospray ionization (ESI) is one of the main techniques used in mass spectrometry (MS) of nonvolatile compounds. ESI is a disordered process, in which a large number of polydisperse droplets are projected from a fluctuating Taylor cone and jet protruding ESI emitter. Here, we disclose a system for sectioning electrospray plumes to discrete packets with millisecond and submillisecond lifetime, which are introduced to the MS orifice, one at a time. A high-speed camera was triggered at 10,000 frames per second to capture consecutive images of the electrospray packets transmitted to the mass spectrometer. We further correlated the high-speed images of electrospray packets with MS signals of a test analyte (acetaminophen). Following computational treatment of the images, we determined the number of droplet observations (<300), average diameter of droplets (∼10-20 μm), and average volume of droplets (few tens of picoliters) in the individual electrospray packets. The result shows that most micrometer droplets (>10 μm) do not have any significant contribution to the MS signals. This finding is in agreement with the prior conjecture that most of the MS signals are mainly attributed to nanodroplets. Based on this finding, one can deduce that only a small number of the initial microdroplets effectively carry analyte molecules that undergo ionization. We discuss that, in future, one may propose a way to "recharge" the emitted initial micrometer droplets to increase the efficiency of conventional ESI setups.

Nanoemulsions and Solid Lipid Nanoparticles with Encapsulated Doxorubicin and Thymoquinone

Nanoemulsions (NEs) and solid lipid nanoparticles (SLNs) are promising drug delivery systems. In this work, paraffin oil NEs and stearic acid SLNs stabilized with Tween 60 and Span 60 have been studied. NEs with an average droplet diameter of ~50 nm and suspensions of SLNs with an average size of ~30 nm are stable to aggregation for more than 90 days. The rates of penetration of lipid particles into cancer cells (C6 and MCF-7) depend on their sizes. After incubation for 1 h, lipid nanoparticles ~50 nm in size penetrate into cells, are distributed in their internal space, and concentrate in the nuclei. The cytotoxicity of doxorubicin- or thymoquinone-loaded NEs and SLNs against MCF-7 and HTC 116 cell lines is higher than the cytotoxicity of the individual substances. Wherein, unloaded NEs and SLNs show low cytotoxicity. The obtained results demonstrate that paraffin oil NEs and stearic acid SLNs are promising to be used as carriers of both lipophilic and amphiphilic drugs, including doxorubicin and thymoquinone. The accumulation of lipid nanoparticles with sizes smaller than 100 nm in cell nuclei is an advantage of such systems for the delivery of anticancer drugs, because this leads to DNA replication suppression followed by cell apoptosis.

Temperature-sensitive and amphiphilic silica nanoparticle-stabilized Pickering emulsion for water shutoff

Due to the shale matrix's low permeability and narrow pore throats, conventional Pickering emulsion plugging agents are unable to effectively seal the formation, making it challenging to create a reliable mud cake that prevents fluid penetration. To address this issue, SiO2 nanoparticles (PEG200-SiO2-OTES) with amphiphilic and temperature-sensitive properties were synthesized for this study. These modified particles were used to prepare temperature-sensitive Pickering emulsions. The aim was to use the emulsion as a carrier to transport the nanoparticles to the specified stratum to release and seal the pore throat. This temperature-sensitive smart Pickering emulsion-based plugging agent (POOP) is used to water shutoff. The produced material had a particle size of around 20 nm, according to structural studies, and had a sensitive temperature response (response temperature of 80 °C). Furthermore, laboratory tests and characterizations revealed that the average diameter of the POOP emulsion droplets was measured to be 1.62 µm, with the emulsion exhibiting a response temperature for breakage at approximately 80 °C.The plugging agent could release PEG200-SiO2-OTES particles at the response temperature of the formation. At this temperature, the plugging agent particles undergo a transition from hydrophilic to hydrophobic, effectively sealing the low permeability (100 mD) and high permeability (1000 mD) formations with sealing efficiencies of up to 83.56% and 75.07% respectively.