Low-energy Method Research Articles

Effects of sputtering gas on the microstructure of Ir thin films deposited by HiPIMS and pulsed DC sputtering

Abstract Due to its chemical inertness, hardness and thermal stability Ir finds a lot of industrial applications. One of the most important field is it use as a substrate material for the monocrystalline diamond heteroepitaxy. However, due to the extreme iridium price, as well as its high melting point, production of bulk iridium substrates is economically unfavorable. In this article we are focused on the Ir thin films production by pulsed DC and HiPIMS sputtering and study the effect of Ar and He working gases on the structure of the growing films. We have found that a sputtering rate reduction given by using of HiPIMS discharge in He is a one of the key factors of the intensified influence of the seed substrate and a growth of thermodynamically unfavorable iridium orientation. This combination can be used as a possible low-energy ion-assisted method for epitaxial growth of materials.

Lead extraction as metallic phase from waste lead oxide-containing glass by redox reaction in hydrothermal treatment

A new low-energy and eco-friendly method for extracting lead from waste PbO-containing funnel glass is required. Conventional methods use either energy intensive smelting reduction at temperatures higher than 1273 K or involve phase separation of the glass, requiring an acid treatment to extract elemental Pb partitioned in one of the decomposed phases as Pb2+ ion. In this study, the mechanism of a unique phenomenon is investigated, involving spontaneous precipitation of metallic lead when PbO-containing glass is subjected to a hydrothermal water environment in a stainless-steel container. The roles of the hydrothermal environment and container materials on the metallic lead precipitation were investigated. The synthesized PbO-containing glass was placed in a container made of stainless steel or pure iron and set in a sealed autoclave with water, which was held at 613 K to provide the hydrothermal conditions. As a result, metallic lead droplets precipitated either on the surface of the glass or the container, whereas an iron oxide (Fe3O4) phase was detected on the surface of the container. Conversely, no metallic lead was observed when the glass and stainless-steel container were heated in dry air. The above results indicate that a hydrothermal environment is necessary for metallic lead precipitation because subcritical water or steam leaches Pb2+ from the glass. In addition, a redox reaction was suggested between the Pb2+ ions transported to the surface of the container and metallic iron in the container to explain metallic lead droplets precipitation.

Synthesis of Hierarchical Porous Silica by Sol‐Gel of Sodium Silicate and Nanoemulsion Templating: Effective Combination Conditions

AbstractHierarchical porous materials have attracted a considerable attention owing to the increased interest in their applications. Hierarchical Porous Silica (HPS) was synthesized by combining the sol‐gel of sodium silicate (SS) and oil in water nanoemulsion (O/W‐NE) templating. The oil droplets of NE acted as pore forming agent and the sol‐gel built the silica framework. The O/W‐NE was prepared by a low energy method, i. e., the phase inversion composition (PIC) method. The influence of pH of SS and NE on HPS was studied. The volume of ammonia, used to induce gelling, was studied as a factor influencing the HPS. The calcined samples were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), FTIR, N2 adsorption and small‐angel X‐ray scattering (SAXS). The results show that the microstructure is highly affected by pH and can be; macropores inserted in a dense matrix; a blend of a dense and a porous structure; or fully hierarchical porous silica. HPS has a specific surface area of 240 m2/g and a large pore volume (1.5 cm3/g) and a surface roughness of 2.95.

Besifloxacin-loaded ocular nanoemulsions: design, formulation and efficacy evaluation.

The purpose of this study was to develop and evaluate nanoemulsions (NEs) containing besifloxacin for ocular drug delivery. Pseudo ternary phase diagrams were constructed using Triacetin (oil), Cremophor® RH 40 (surfactant), and Transcutol®P (co-surfactant) to identify NE regions. Six formulations were developed by low-energy emulsification method and then evaluated for size, refractive index, pH, osmolality, viscosity, anddrug release.After accelerated physical stability and bovine conrneal permeation studies,NE2 was chosen as optimized formulationforantimicrobial efficacy, and hen's egg test-chorioallantoic membrane (HET-CAM)tests. The particle size of optimum NE was 14nm with a narrow size distribution. Moreover, other physicochemical characterizations were in the acceptable range for ocular administration. Besifloxacin-loaded NEs demonstrated sustained release pattern and 1.7-fold higher permeation compared with the control suspension in the ex vivo transcorneal permeation study. HET-CAM test indicated no irritation, and HL% revealed no damage to the tissue, so the optimum NE is well tolerated by the eye. In vitro antimicrobial evaluation, showed comparative efficacy of lower drug-loaded NE (0.2%) versus 0.6% besifloxacin suspension (equal concentration to commercial besifloxacin eye drop). In conclusion, besifloxacin-loaded NEs could be considered as a suitable alternative to the marketed suspension for treatingbacterial eyeinfections.

Low-Energy Separation Technique on Purification of Unsaturated Fatty Acids of Palm Stearin using Methanol Crystallization Method

This paper discussed the development of a low-energy and cost-effective separation technique of saturated fatty acids (S FAs) from Malaysian Palm Stearin to purify the unsaturation level of its fatty acids. Unsaturated fatty acids (U FAs) pose great benefits in nutritional value and also can be utilized as a raw material in various food or non-food applications. A methanol crystallization separation method was introduced by manipulating the storage temperature as well as the mixture ratio of palm stearin fatty acids (PSFAs) and methanol as a solvent. The separated compounds were characterized using Fourier-transform infrared (FTIR) spectroscopy, proton (1H-NMR), and carbon (13C-NMR) spectroscopy analysis techniques. The fatty acids composition for both U FAs and S FAs were determined through gas chromatography (GC)analysis technique. The highest separation yield was about 98% (wt.), using a mixture of PSFA:methanol; 1:9 (w/v) at the temperature of -20 °C. This method was successfully separated and purified the U FAs by increasing the unsaturation level of fatty acids about 172% as the final iodine value was about 98 compared to the initial value was at 36. The low-energy methanol crystallization separation method is a cheaper method compared to the conventional high-energy fractional distillation process and positively to be up scaled at industrial level.

Nano-emulsions of the essential oil of Baccharis reticularia and its constituents as eco-friendly repellents against Tribolium castaneum

Nanoproducts based on natural products have been studied as ecologically and economically sustainable alternatives for crop pest control. Baccharis reticularia DC. is a shrub endemic to Brazil, which leaves are traditionally used in aromatic medicinal baths. This study aims to evaluate the repellent activities of nano-emulsions containing the B. reticularia phytochemically characterized essential oil and some of its monoterpene constituents (limonene, α-pinene, and β-pinene) against Tribolium castaneum (Herbst). Essential oil was obtained by hydrodistillation of fresh leaves and stems and yielded 0.28 % (w/w). The main constituents of the essential oil were: limonene (14.6 %), β-myrcene (12.6 %), and bicyclogermacrene (12.5 %). The required hydrophile-lipophile balance (rHLB) of the nano-emulsions were: 13 (α-pinene) and 15 (essential oil, limonene, and β-pinene). All nano-emulsions showed mean droplet sizes bellow 200 nm and remain stable, at least, for 28 days (limonene), 90 days (β-pinene), or 150 days (essential oil and α-pinene). All nano-emulsions exhibited repellent activity against T. castaneum at 8.8 μg/cm2. Limonene and α-pinene were the most active nano-emulsions, showing significant repellent action at 1.1 μg/cm2, which indicates that these compounds contribute to the repellent action of the essential oil of B. reticularia. The present study opens perspectives for the utilization of B. reticularia essential oil and its constituents as raw material of new promising nanopesticides produced using a low energy, solvent-free and ecofriendly method. Thus, this work contributes significantly to the search for new ecologically correct strategies for the control of T. castaneum.

Black pepper essential oil nanoemulsions formulation using EPI and PIT methods

In this study, black pepper essential oil nanoemulsions formulated using low-energy methods (emulsion phase inversion and phase inversion temperature) were compared. In both the methods, optimum components' concentration was 10% of essential oil, 20% of Tween 80, and 70% of distilled water. All nanoemulsions were unchanged after centrifuging at 825 or 1,467 g for 10 min and were more stable when kept at 30°C. Phase inversion temperature nanoemulsions quickly increased droplet size and polydispersity index after 2 weeks, then separated, and created creaming layer on the top after 4 weeks while emulsion phase inversion nanoemulsions were still homogeneous for 4 weeks. However, phase inversion temperature nanoemulsions were more stable than emulsion phase inversion nanoemulsions during heating–cooling cycles. In addition, the loading efficiency of emulsion phase inversion samples was also higher than phase inversion temperature samples, 92.13% and 81.52%, respectively. Practical applications Black pepper essential oil such as other plant essential oils has proved their bioactivity of antimicrobial, antioxidant. Therefore, utilization of essential oil in food industry has set a new trend as a natural food additive. However, essential oils are not easy to add into food products due to the presence of hydrophobic and volatile components. Nanoemulsion is expected to be one of suitable systems for dispersing essential oil in food environment. Essential oil nanoemulsion made from black pepper, very popular spice all over the world, has potential for using as a food preservative for not only many food techniques, but also many kinds of food: dripping fresh food material, spraying on food material, using as seasoning for canning food, or other processing food. Novelty impact statement In this study, Vietnamese black pepper (Piper nigrum) essential oil nanoemulsions were successfully formulated using the phase inversion temperature (PIT) method. Both the emulsion phase inversion (EPI) and PIT methods formed small droplet of 32.4 and 82.4 nm, respectively. However, EPI nanoemulsions were not only more homogeneous, but also more steady than PIT nanoemulsions in our experiment condition.

Hydrothermal Synthesis of Nd–Fe–B Nanoparticles with Enhanced Magnetic Properties by Nd Content Tunning and Dy Doping

This paper reports a novel, facile and low-energy consumption chemical method to synthesise Nd–Fe–B and Dy-substituted Nd–Fe–B magnetic nanoparticles with enhanced magnetic properties. NdxFe95-xB5 (15≤ x≤ 40) and Nd35-yDyyFe60B5 (0≤ y ≤8) magnetic nanoparticles were synthesised using a hydrothermal method, followed by a reduction-diffusion annealing process. We carried out a detailed experimental study of the effects of Nd content and Dy substitution on the phase assemblage and magnetic properties in the two systems. The results indicated that the coercivity of the Nd–Fe–B powders increased with increasing Nd content, and the maximum coercivity measured was 262.5 kA/m for Nd40Fe45B5 (by weight percentage). Conversely, the saturation magnetisation decreased with increasing Nd content. When the addition of Dy was less than 8 wt%, both the coercivity and the saturation magnetisation varied monotonically with the amount of Dy added, and a coercivity of 548.9 kA/m was measured for Nd27Dy8Fe60B5. The results show that hydrothermal method followed by a reduction-diffusion process is simple and economical in preparing Dy-substituted Nd2Fe14B magnetic nanoparticles, and the controllable and enhanced magnetic properties can be realised by simply adjusting the ratio of raw materials. This is also a good complement to the preparation of Nd–Fe–B nanoparticles by chemical methods.

Potential Development of Sustainable 3D-Printed Meat Analogues: A Review

To mitigate the threat of climate change driven by livestock meat production, a multifaceted approach that incorporates dietary changes, innovative product development, advances in technologies, and reductions in food wastes/losses is proposed. The emerging technology of 3D printing (3DP) has been recognized for its unprecedented capacity to fabricate food products with intricate structures and reduced material cost and energy. For sustainable 3DP of meat substitutes, the possible materials discussed are derived from in vitro cell culture, meat byproducts/waste, insects, and plants. These material-based approaches are analyzed from their potential environmental effects, technological viability, and consumer acceptance standpoints. Although skeletal muscles and skin are bioprinted for medical applications, they could be utilized as meat without the additional printing of vascular networks. The impediments to bioprinting of meat are lack of food-safe substrates/materials, cost-effectiveness, and scalability. The sustainability of bioprinting could be enhanced by the utilization of generic/universal components or scaffolds and optimization of cell sourcing and fabrication logistics. Despite the availability of several plants and their byproducts and some start-up ventures attempting to fabricate food products, 3D printing of meat analogues remains a challenge. From various insects, powders, proteins (soluble/insoluble), lipids, and fibers are produced, which—in different combinations and at optimal concentrations—can potentially result in superior meat substitutes. Valuable materials derived from meat byproducts/wastes using low energy methods could reduce waste production and offset some greenhouse gas (GHG) emissions. Apart from printer innovations (speed, precision, and productivity), rational structure of supply chain and optimization of material flow and logistic costs can improve the sustainability of 3D printing. Irrespective of the materials used, perception-related challenges exist for 3D-printed food products. Consumer acceptance could be a significant challenge that could hinder the success of 3D-printed meat analogs.

Nanoemulsions with Chloroaluminium Phthalocyanine and Paromomycin for Combined Photodynamic and Antibiotic Therapy for Cutaneous Leishmaniasis.

BackgroundPhotodynamic therapy (PDT) using chloroaluminium phthalocyanine (ClAlPc) and paromomycin sulfate (PM) can be effective against New World Leishmania species involved in cutaneous leishmaniasis (CL). The aim of this study is to assay the skin permeation and the antileishmanial effects of a nanoemulsion (NE) containing both ClAlPc and PM in experimental CL by Leishmania (Viannia) braziliensis.Material and MethodsCremophor ELP/castor oil-based NEs were prepared by a low-energy method and characterized for their physicochemical parameters. The NEs were used to deliver both ClAlPc and PM to leishmania cells. The in vitro toxicity of NEs were tested in vitro against L. (V.) braziliensis and THP-1 cells. The in vivo toxicity was assessed in non-infected BALB/c mice. Ex-vivo permeation and retention studies using healthy mice skin were also conducted. Finally, the in vivo activity of NE-PM+ClAlPc after PDT was tested in BALB/c mice infected with parasites.ResultsNEs are colloidally stable with average droplet diameter of 30 nm, polydispersity index (PDI) below 0.2, and zeta potential near zero. Both promastigotes and intracellular amastigotes treated with NE-PM, NE-ClAlPc and NE-PM+ClAlPc were inhibited at >50%, >95%, >88%, respectively, after PDT with a phototoxic index (PI) >1.2. No skin ClAlPc permeation was observed. In contrast, PM skin permeation was 80-fold higher using PM-loaded NE formulation in comparison to aqueous PM solution. Topical treatment with NE formulations showed no signs of local toxicity or genotoxicity. In addition, concentrations of PM between 27.3 - 292.5 μM/25 mg of tissue were detected in different organs. In vivo, the NE-PM+ClAlPc treatment did not reduce skin lesions.ConclusionThe Cremophor ELP/castor oil NE formulation increases the permeation of PM through the skin and can be used to co-deliver PM plus ClAlPc for combined PDT protocols. However, the lack of efficacy in the in vivo model evidences that the therapeutical scheme has to be improved.

Optimization of Surfactant- and Cosurfactant-Aided Pine Oil Nanoemulsions by Isothermal Low-Energy Methods for Anticholinesterase Activity.

Highly stable pine oil-loaded nanoemulsions were evaluated for nutraceutical and storage stability applications. Pine oil-loaded nanoemulsion preparation was done with pine oil as the oily phase and additionally with different ratios of the non-ionic surfactant (Tween 80) and cosurfactant (ethanol) in an aqueous solution using the isothermal low-energy or spontaneous emulsification method. A transparent and stable nanoemulsion was obtained with a combination of pine oil (5 wt %), surfactant mixture (35 wt %), and water quantity sufficient (qs) by the isothermal low-energy method. The mean droplet size and ζ-potential of the fabricated nanoemulsion were ≈14 nm and −3.4 mV, respectively. The size of the transparent nanoemulsion increased to ∼45 nm and showed turbidity at 60 °C. Microrheological investigation highlighted the gel–sol–gel conversion in the presence of applied angular frequency at 25 °C. The loss modulus shifted to lower frequency at 60 °C in comparison to other temperatures. The anticholinesterase (AChE) inhibition activity of the pine oil-loaded nanoemulsion suggested a possible therapeutic value, and at 0.10% concentration of the nanoemulsion, the AChE inhibition activity was ≈95.72 ± 5.59%. These studies have important implications in fabrication and optimization of a nanoemulsion as a delivery system for combating reminiscence in Alzheimer’s disease and application in the nutraceutical-based industry. This isothermal low-energy method offers an advantage of preparing an edible oil delivery system using simple and rapid operational parameters.

Novel Magnetic Nano Silica Synthesis Using Barley Husk Waste for Removing Petroleum from Polluted Water for Environmental Sustainability

Water contamination by petroleum and its byproducts presents a major challenge worldwide. It is critical that sustainable treatment methods be employed for the removal of such contaminants from polluted water. For this investigation, magnetic nano silica (M-NS) was synthesized using agricultural waste from barley husk using a two-step process that is environmentally friendly and uses green chemistry synthesis. The barley husk waste was used as a precursor for the synthesis of nano-silica following a low energy and sustainable method of acid reflux and heat treatment. Nano-silica was then used for the synthesis of M-NS, with the addition of a magnetic solution of Fe3O4 nanoparticles. The magnetic nano-silica particles were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Zeta potential analysis (ZETA) and X-Ray Diffraction (XRD). Magnetic nano-silica particles were observed to have an average diameter of 162 nm and appeared to be hydrophobic, with a large surface area of ~120 m2/gm. Due to these characteristics, magnetic nano-silica was used as an adsorbent for the removal of petrol contaminants from water. The experimental procedure showed that only 0.6 gm. of M-NS was used on 40 mg/L concentration of petroleum and the experiments recorded a high uptake efficiency of 85%. The sorption was shown to be an effective process since a high amount of petroleum was removed. The study further demonstrates that as the amount of sorbent is increased, the sorption capacity also increases until an equilibrium is reached. The results of this study establish that synthesis of M-NS, using environmentally sustainable processes, has the required characteristics to serve as sorbent for petroleum and its byproducts from contaminated water, thus enhancing environmental sustainability.

Efficacy of nanoemulsion with Pterodon emarginatus Vogel oleoresin for topical treatment of cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) is a neglected tropical skin disease caused by the protozoan genus Leishmania. The treatment is restricted to a handful number of drugs that exhibit toxic effects, limited efficacy, and drug resistance. Additionally, developing an effective topical treatment is still an enormous unmet medical challenge. Natural oils, e.g. the oleoresin from P. emarginatus fruits (SO), contain various bioactive molecules, especially terpenoid compounds such as diterpenes and sesquiterpenes. However, its use in topical formulations can be impaired due to the natural barrier of the skin for low water solubility compounds. Nanoemulsions (NE) are drug delivery systems able to increase penetration of lipophilic compounds throughout the skin, improving their topical effect. In this context, we propose the use of SO-containing NE (SO-NE) for CL treatment. The SO-NE was produced by a low energy method and presented suitable physicochemical characteristic: average diameter and polydispersity index lower than 180 nm and 0.2, respectively. Leishmania (Leishmania) amazonensis-infected BALB/c mice were given topical doses of SO or SO-NE. The topical use of a combination of SO-NE and intraperitoneal meglumine antimoniate reduced lesion size by 41 % and tissue regeneration was proven by histopathological analyses. In addition, a reduction in the parasitic load and decreased in the level of IFN-γ in the lesion may be associated, as well as a lower level of the cytokine IL-10 may be associated with a less intense inflammatory process. The present study suggests that SO-NE in combination meglumine antimoniate represents a promising alternative for the topical treatment of CL caused by L. (L.) amazonensis.

Solution Combustion-Mechanochemical Syntheses of Composites and Core-Shell xLi2MnO3·(1 – x)LiNi0.5Mn0.3Co0.2O2 (0 ≤ x ≤ 0.7) Cathode Materials for Lithium-Ion Batteries

A combination of the solution combustion and mechanochemical syntheses (SC-MS) presents a facile, low-energy, and cost-effective method to prepare layered lithium-rich oxide (LLO) composites and co...

Larvicide Activity on Aedes aegypti of Essential Oil Nanoemulsion from the Protium heptaphyllum Resin.

The aim of this work was to prepare a nanoemulsion containing the essential oil of Protium heptaphyllum resin and to evaluate the larvicidal activity and the residual larvicidal effect against Aedes aegypti. The essential oil was identified by gas chromatography coupled to a mass spectrometer, and the nanoemulsions were prepared using a low-energy method and characterized by photon correlation spectroscopy. The results indicated the major constituents as p-cimene (27.70%) and α-Pinene (22.31%). Nanoemulsions had kinetic stability and a monomodal distribution in a hydrophilic-lipophilic balance of 14 with particle diameters of 115.56 ± 1.68 nn and zeta potential of −29.63 ± 3.46 mV. The nanoemulsion showed larvicidal action with LC50 = 2.91 µg∙mL−1 and residual larvicidal effect for 72 h after application to A. aegypti larvae. Consequently, the nanobiotechnological product derived from the essential oil of P. heptaphyllum resin could be used against infectious disease vectors.

Physicochemical Characteristics of Four Limonene-Based Nanoemulsions and Their Larvicidal Properties against Two Mosquito Species, Aedes albopictus and Culex pipiens molestus.

Simple SummaryThe repeated use of synthetic insecticides against mosquitoes has posed negative impacts on the environment; hence, the utilization of more ecofriendly mosquito control products is deemed necessary. Nanoformulations of phytochemical substances with a safer profile for the environment have been considered potential larvicidal agents against mosquitoes. In this perspective, we formulated 4 (R)-(+)-limonene based oil-in-water nanoemulsions by low and high energy methods, and we studied their physicochemical characteristics (e.g., viscosity, stability, mean droplet diameter, polydispersity index). In addition, we evaluated their larvicidal properties against two mosquito species of great medical importance, Culex pipiens molestus and Aedes albopictus. Laboratory bioassays showed that limonene-based nanoemulsions either improved or did not affected limonene toxicity, depending on the delivery system and mosquito species. In conclusion, all tested limonene-based nanoemulsions provided sufficient toxic effects against mosquito larvae, serving as potential formulations for mosquito control applications.Negative impacts on the environment from the continuous use of synthetic insecticides against mosquitoes has driven research towards more ecofriendly products. Phytochemicals, classified as low-risk substances, have been recognized as potential larvicides of mosquitoes; however, problems related to water solubility and stability are limiting factors for their use in mosquito control programs in the field. In this context, many researchers have focused on formulating essential oils in nanoemulsions, exploiting innovative nanotechnology. In the current study, we prepared 4 (R)-(+)-limonene oil-in-water nanoemulsions using low and high energy methods, and we evaluated their physicochemical characteristics (e.g., viscosity, stability, mean droplet diameter, polydispersity index) and their bioactivity against larvae of two mosquito species of great medical importance, namely, Cx. pipiens molestus and Ae. albopictus. According to the dose–response bioassays with the limonene-based nanoemulsions and pure limonene (dissolved in organic solvent), the tested nanoformulations improved the activity of limonene against Ae. albopictus larvae, while the performance of limonene was either the same or better than limonene against Cx. pipiens molestus, depending on the applied system. Overall, we achieved the production of limonene-based delivery nanosystems, with sufficient lethal properties against mosquito larvae to consider them promising larvicidal formulations applicable to mosquito breeding sites.

Studies on the quality and moisture distribution of kiwifruit dried by freeze drying combined with microwave vacuum drying

AbstractThe drying quality of kiwifruit dried by a combination of freeze drying and microwave vacuum drying (FD‐MVD) in terms of drying time, appearance quality and microstructure. The results showed that the quality of FD‐MVD products was highest with FD 12 h because the lowest volume density and close to the color of single FD samples. The optimal microwave power for the MVD process was found to be 0.30 W/g. The microstructure of FD 8 h samples was maintained very well due to the whole cell structure between the center and the edge of the kiwifruit. This is because that the moisture content at the edges and centers was identical in the FD‐MVD samples with FD 8 h. However, in FD‐MVD samples with FD 10 h and FD 12 h, the moisture content at the center was significantly higher than at the outer ring, which resulted in obvious shrinking and folding of cell structure. Therefore, FD 12 h was considered the optimal moisture conversion point because it resulted in a good appearance quality. FD 8 h was the optimal moisture transfer point when the microstructure, drying time and drying energy were considered jointly.Practical ApplicationsKiwifruit is rich in nutrients and is planted in over 80 countries worldwide. FD method used to dry kiwifruit consumes large amounts of energy although results in good quality products. FD‐MVD dried kiwifruit requires less energy to produce and its quality is similar to that of kiwifruit subjected to FD only. This study describes a new, low energy method of kiwifruit drying that has possible implications for large‐scale commercial production. In addition, effect of different cell structure of center and edge in kiwifruit on microstructure afford a new quality judgment method during drying for similar materials.

A feasibility assessment of a retrofit Molten Carbonate Fuel Cell coal-fired plant for flue gas CO2 segregation

This work considers the use of a Molten Carbonate Fuel Cell (MCFC) system as a power generation and CO2 concentrator unit downstream of the coal burner of an existing production plant. In this way, the capability of MCFCs for CO2 segregation, which today is studied primarily in reference to large-scale plants, is applied to an intermediate-size plant highlighting the potential for MCFC use as a low energy method of carbon capture. A technical feasibility analysis was performed using an MCFC system-integrated model capable of determining steady-state performance across varying feed composition. The MCFC user model was implemented in Aspen Custom Modeler and integrated into the reference plant in Aspen Plus. The model considers electrochemical, thermal, and mass balance effects to simulate cell electrical and CO2 segregation performance. Results obtained suggest a specific energy requirement of 1.41 MJ kg CO2−1 significantly lower than seen in conventional Monoethanolamine (MEA) capture processes.

Application of Osmotic Dehydration and Ultrasound to Enhance Hazelnut Oil Extraction

Hazelnut oil is a valuable product which can be used in various applications not limited to food processing, cosmetic product, and pharmaceutical industry. Traditionally, heating process is used to remove the moisture in various nuts and seeds prior to oil extraction stage in the industry which is relatively energy consuming. In this study, osmotic dehydration which is normally used as a pretreatment in fruit dehydration process was applied as a low-energy moisture removal method during the ultrasound-assisted extraction of oil from hazelnut. The effects of ultrasound amplitude, concentration of osmotic solution, and dehydration time on the yield and characteristics of hazelnut oil obtained were investigated in this study. Concentration of osmotic solution and dehydration time showed more significant effects on water removal as compared with ultrasound amplitude. Higher oil yield of 93% was achieved with the introduction of osmotic dehydration as pretreatment without negative impacts on quality of oil as compared with 88% oil yield in extraction without dehydration aid. The values for quality of oil obtained were in the range of 25–40 g/100 g oil, 0.5–1.1 g/100 g oil, and 2–6 mEq/kg for iodine, free fatty acid, and peroxide values, respectively. All the values were in the range of edible oil standard. Therefore, osmotic dehydration is a promising pretreatment method to enhance oil yield during extraction process in food industry.

Evaluation and manipulation of the key emulsification factors toward highly stable PCM-water nano-emulsions for thermal energy storage

PCM emulsions represent a common type of fluid media for thermal energy storage (TES) systems. However, a major challenge for their application is to maintain a stable homogeneous fluid. Reduction of the droplet size is one of the most effective approaches for improving stability, such as the preparation of nano-emulsions. This work aims to develop stable PCM-water nano-emulsions prepared with n-hexadecane by manipulating the key emulsification factors, particularly the emulsifier combinations and process conditions. Two low-energy emulsification methods, phase inversion temperature (PIT) and emulsion inversion point (EIP), were applied to prepare the nano-emulsions, using Brij L4 as the emulsifier. Several important properties of the emulsions were evaluated including droplet size distribution, conductivity, and rheological characteristics and the stability of emulsions over extended periods and multiple freeze-thaw cycles. Moreover, the thermal performance for their potential application in TES systems were examined. Eventually, nano-emulsions with small and uniform droplets were obtained by both PIT and EIP methods with suitable emulsifier concentrations. The smallest droplet size (~60 nm) was attained with 11% emulsifier and 30% PCM by the PIT method, and the most stable emulsion attained with 15% of emulsifier and 30% of PCM. The PCM nano-emulsions behaved as a Newtonian liquid with a good fluidity and a superior stability over long-time storage and freezing-cycles. The degree of supercooling was reduced with the addtion of nano SiO2 as a nucleating agent. The findings from the study are useful for better understanding of the controlling factors and further development of stable and effective nano-emulsions.