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This study aimed to investigate the effect of the application of different freeze-drying conditions on the process's kinetics and the sorption properties of dried apples. Slices of apples were frozen and subjected to a freezing-drying process with different combinations of shelf temperature (−20, 10, 20, and 30 °C) and pressure (37, 63, 103, and 165 Pa). During the freeze-drying, the temperature in the centre of the material was recorded. The moisture content in the dried material and changes in the water content in dried apples stored at a humidity of 75.3% were obtained. The Midilli et al. model was used to describe the drying kinetics of the freeze-drying with a good fit. Drying time increased from 660 (variant with a constant shelf temperature of 30 °C, pressure 63 Pa) to 1305 min (variants with temperatures −20:10:20:30 °C, pressure 63 Pa). For this reason, the most favourable experimental parameters were a temperature of 30 °C and a pressure of 63 Pa. However, applying these parameters caused higher absorption of water vapour during storage. Therefore, the selection of freeze-drying parameters should also be related to the expected properties of the final product. [ABSTRACT FROM AUTHOR]

Grapes are widely consumed worldwide in various forms, including fresh and dried, or processed into products like juice, vinegar, wine, and so on. Anthocyanins, mainly found in grapes, are responsible for various health-promoting effects and contribute to their colours such as red, purple, and blue. Although grapes contain a high quantity of anthocyanins, their bioavailability is considered limited. Anthocyanins may be absorbed by the gastrointestinal wall, undergo intensive first-pass metabolism, and emerge as metabolites in systemic circulation. A significant percentage of some anthocyanins can enter the large intestine and undergo breakdown induced by digestive system microorganisms. Several factors, such as pH, temperature, light, and solvents, can affect anthocyanin bioavailability, and processing grapes into products may impact their bioavailability. Considering the high market share of grapes and grape products, it is important to understand the effects of processing on anthocyanin bioavailability. This review discusses changes in the bioavailability of anthocyanins found in grapes and grape products during food processing, the effect of extraction conditions on bioavailability, as well as the health-promoting effects of grapes and grape products.

Grapes are widely consumed worldwide in various forms, including fresh and dried, or processed into products like juice, vinegar, wine, and so on. Anthocyanins, mainly found in grapes, are responsible for various healthpromoting effects and contribute to their colours such as red, purple, and blue. Although grapes contain a high quantity of anthocyanins, their bioavailability is considered limited. Anthocyanins may be absorbed by the gastrointestinal wall, undergo intensive first-pass metabolism, and emerge as metabolites in systemic circulation. A significant percentage of some anthocyanins can enter the large intestine and undergo breakdown induced by digestive system microorganisms. Several factors, such as pH, temperature, light, and solvents, can affect anthocyanin bioavailability, and processing grapes into products may impact their bioavailability. Considering the high market share of grapes and grape products, it is important to understand the effects of processing on anthocyanin bioavailability. This review discusses changes in the bioavailability of anthocyanins found in grapes and grape products during food processing, the effect of extraction conditions on bioavailability, as well as the healthpromoting effects of grapes and grape products. [ABSTRACT FROM AUTHOR]

Electrolytic copper foils are functional basic raw material in the electronics manufacturing industry. Due to different electrolytic process conditions (such as types of additives, current density, electrodeposition time, etc.), different microstructures will be formed during the raw foil manufacturing process, such as grain size, morphology, twinning, and texture. These microstructures are closely related to the performance of the electrolytic copper foil (ECF). Texture is one key aspect among them, as it affects various properties of ECF to a certain extent, including tensile strength, elongation, and hardness. Therefore, texture is receiving increasing research attention. This article reviews recent studies on the texture of ECF, analyzes the influence of electrolytic process conditions on the formation of texture, and explores the intrinsic relationship between texture and the mechanical properties of ECF. It also provides an outlook on the mechanisms for the study of ECF texture and its future development. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is a promising technology for renewable energy production from organic waste. In order to maximize the produced biogas quantity and quality, this paper deals with the optimization of the AD process in a CSTR bioreactor of a full-scale biogas plant. For this purpose, a novel approach was adopted coupling, a highly complex BioModel for AD simulation, and a gradient-based optimization method. In order to improve AD performance, the dosages of various types of biological additives, the dosages of inorganic additives, and the temperature in the bioreactor were optimized in three different scenarios. The best biogas quality was obtained using multi-objective optimization, where the objective function involves the following two conflicting objectives: the maximization of biogas production and minimization of the needed heating energy. The obtained results show that, potentially, the content of C H 4 can be increased by 11%, while the contents of H 2 , H 2 S , and N H 3 can be reduced by 30%, 20%, and 81% when comparing the simulation results with the experimental data. The obtained results confirm the usefulness of the proposed approach, which can easily be adapted or upgraded for other bioreactor types. [ABSTRACT FROM AUTHOR]

The aim of copper hydrometallurgy is to produce high-quality cathode copper with the lowest energy consumption and the highest current efficiency. How to achieve this objective has become the focus of research. The anode material significantly influences the anode overpotential, current efficiency and cathode copper quality. Therefore, developing energy-saving anodes holds great practical significance for the copper electrowinning industry. The introduction of alloying element such as Ag, Ca, Co and Re into the lead alloy anode can enhance the mechanical strength of lead alloy, inhibit lead dissolution, and improve its electrocatalytic activity and corrosion resistance; the fabrication of composite anodes with active layers such as β-PbO2, IrO2-Ta2O5, TiB2/β-PbO2 and Co3O4 on conductive substrates, which possess excellent conductivity and catalytic activity, can enhance the anode’s corrosion resistance and reduce the oxygen evolution overpotential; it is found that graphite, lead with a three-dimensional structure and the PANI/Co3O4 composite can enhance both the active specific surface area and current efficiency of anode. By adjusting the copper acid ratio in the electrolyte from 0.25 to 0.30, and adding guar gum, thiourea and Co2+, the performance of the anode can be enhanced and the quality of the cathode copper can be improved. Furthermore, optimizing process conditions such as the temperature of the electrolyte and electrode spacing can also impact the anode’s lifespan and catalytic activity. In this paper, energy-saving measures for hydrometallurgical copper refining were mainly introduced from three aspects: the development of oxygen-evolving anodes, adjustments to the solution system, and optimization of process parameters. Finally, the future development direction of energy-saving in copper electrowinning was discussed.

The aim was optimization of sweet potatoes (Ipomoea batatas) drying process conditions with RSM to obtain high quality product is very vital as improper drying conditions can affect the composition of the dried sweet potatoes and thereby increases the risk of running into deterioration of the nutrient contents of the product and loss. Matured sweet potatoes were processed by washing, peeling and cut into required size. Samples obtained were dried in triplicate using DHG-9101 laboratory drying oven at different temperatures of 60, 65, and 70°C and time of 480, 540 and 600 minutes at thickness size of 4, 5 and 6 mm by employing Design of Experiment (DOE). Statistical analysis based on central composite design was carried out. The significant factors were identified. The optimum conditions obtained were at a temperature of 60°C, time of 480 minutes and thickness of 4 mm which resulted in final moisture content of 13.96%. From these results obtained, the use of response surface methodology in drying operation for optimizing sweet potatoes could be used. For further research, higher temperatures at lower drying time could be implemented. Also, other drying methods such as freeze drying and osmotic drying can be explored. [ABSTRACT FROM AUTHOR]

Summary: Herein, some quality characteristics (water content, pH, antioxidant activity and sugar contents) of fresh garlic (Taşköprü, Türkiye) and black garlic, which were produced under various ageing temperatures (60 °C, 70 °C and 80 °C) and durations (30, 45 and 60 days), and the effect of ageing processes on these quality characteristics were determined. The ageing process caused a reduction (P < 0.01) in the water content and pH value of the samples, while enhanced (P < 0.01) antioxidant activity and increased (P < 0.01) the content of glucose, fructose, sucrose and reducing sugar. Both the water content and pH value of the black garlic declined significantly with increasing ageing temperature, while only pH value of the black garlic declined significantly with increasing ageing duration. Ageing samples at 60 °C and 70 °C exhibited higher antioxidant activity than those aged at 80 °C, which had similar activity to the fresh samples. A similar status was observed when the ageing temperature was prolonged to 60 days. Sucrose concentration of the black garlic samples raised with elevating the ageing temperature and declined with prolonging the duration. While a remarkable decline in the reducing sugars of the black garlic samples was observed with elevating the ageing temperature, the maximum concentration was recorded on the 45th day of the ageing process. However, the black garlic samples produced at 60 °C for 60 days or 70 °C for 30 days could be recommended to get a final product with good antioxidant capacity, adequate amount of free sugars, pH value and water content. [ABSTRACT FROM AUTHOR]

The comparison of ion concentrations, pH index, and conductivity in distilled and ground water after exposure to low-temperature plasma formed by barrier and bubble discharges is performed. It has been found that in the case of groundwater, the best performance for the production of NO3− anions is provided by the discharge inside the gas bubbles. For distilled water, the barrier discharge in air, followed by saturation of water with plasma products, is the most suitable from this point of view. In both treatments, the maximum energy input into the stock solution is ensured. After 10 min treatment of ground water, the pH index increases and then it decreases. The obtained numerical indicators make it possible to understand in which tasks the indicated treatment modes should be used, their comparative advantages, and disadvantages. From the point of view of energy consumption for obtaining approximately equal (in order of magnitude) amounts of NO3− anions, both types of discharge treatment are suitable. The research results point to a fairly simple way to convert salts (calcium carbonates) from an insoluble form to soluble one. Namely, when interacting with NO3− anions, insoluble carbonates pass into soluble nitrates. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hot water shower sterilization is a crucial part in the production of liquid pharmaceutical products. This work was conducted to experimentally investigate the heat transfer for hot water shower sterilizers by examining the effects of various parameter changes. Heating and cooling runs were performed using a lab-scale test bench for a 1000 ml glass bottle and 500 ml flexible polypropylene infusion bag. The temperature range under investigation spanned from 20 °C to 80 °C, covering a significant portion of the range for heating and cooling of the sterilization process as well as typical temperatures used in food pasteurization. Temperature measurements were taken at three distinct locations within the products. High-speed and infrared photography was employed to explore the varying film regimes on the products. The results indicated that increasing the surface-averaged volume flow rate from 20 m3 h-1 to 40 m3 h-1 per m2 of spraying surface reduced the cooling and heating rates for the bag. However, increasing the surface-averaged volume flow rate correlated to an increase in cooling and heating rates for the bottle. Additionally, configuring a distribution tray above the products with a greater number of smaller holes resulted in reduced sensitivity of the surface-averaged volume flow rate on the cooling rates and an overall decrease in cooling time. A higher hole plate porosity was identified to increase the heating rate of bags. In summary, this study offers valuable insights into how various parameter changes impact the heat transfer in bottles and bags during hot water shower sterilization. • Decreased heating and cooling rates for higher volume flow rates for bags identified. • Faster cooling with a greater number of smaller distribution tray holes achievable. • Agitation effect of flexible bag wall on temperature stratification in bags measured. • Importance of heat transfer of the bags' underside in sterilizers identified. • Increased hole plate porosity increased heating rate. [ABSTRACT FROM AUTHOR]

The present work, first detailed study in its nature, introduces wall curl as a source of geometric inaccuracy in the novel Incremental Sheet Forming (ISF) process, and aims at investigating role of the residual stresses, stretching force and process conditions on formation of the curl. A series of metal components are formed by varying the conditions. The curl height, residual stresses (surface, mean and equivalent) and stretching force are determined and their correlations are analyzed. The analysis reveals that curling is strongly influenced by the residual stresses in a way that the curl height increases linearly as their magnitude increases. Similarly, an increase in degree of non-uniformity in the through-thickness stress distribution promotes curling. The increase in stretching force, however, diminishes curling reasoning to reduction in the residual stresses. As regard the conditions, feed rate does not show any effect while mild annealing, greater tool diameter, smaller step size, and lower forming angle and rotation are found conducive to minimize curling. The geometric errors in wall and bottom of the produced parts (i.e., curling and pillowing) are found to show an interesting inverse relationship. The reported results are very useful to deepen the process mechanics and will also prove helpful in simultaneously controlling the two types of errors.

The performance of Polystyrene microporous foaming (PS-MCF) materials is influenced by their microstructures. Therefore, it is essential for industrializing them to investigate the relationship between their microstructure and material properties. In this study, the relationship between the microstructure, compressive property, and thermal conductivity of the PS-MCF materials was studied systematically. The results show that the ideal foaming pressure of PS-MCF materials, obtaining compression performance, is around 20 MPa. In addition, the increase of temperature causes the decrease of sample density. It effects that the compression modulus and strength increase with the decrease of foaming temperature. Because the expansion rate and cell diameter of the PS-MCF materials reduce the thickness of cell wall, they are also negatively correlated with their mechanical properties. Moreover, there is a negative linear correlation between the thermal conductivity and cell rate, whereas the cell diameter is positively correlated with the thermal conductivity.

This research studied the optimization of the production of alkyd resin from dehydrated castor oil (Ricinus communis) and soybean oil (Glycine max) respectively. The natural content of iodine in soybean oil was sufficient for producing drying alkyd resin while refined castor oil has low iodine content; hence it was severely dehydrated at high temperature to increase its iodine value from 83 to 130, which made it suitable for alkyd resin production. Nine different samples of medium oil alkyd resins of 50% oil length were synthesized from each oil at different reaction conditions using monoglyceride method, which involved mixing of appropriate amount of each oil with glycerol via alcoholysis, followed by the addition of phthalic anhydride via esterification. The acid value was observed to decrease with time during the esterification process and this decrease was a measure of alkyd resin production. The outcomes of the standardization of the soybean and castor oil modified resins through coating analyses revealed that both have desirable commercial attributes in terms of chemical resistance, set to touch, solubility in solvent media and drying time though at any given similar production conditions, soybean oil modified resins have better qualities due to their lower acid values. The kinetic studies carried out indicated that only first order and second order kinetics fitted into the experiment data. Time, temperature and phthalic anhydride dosage were the three independent factors studied and optimized using Composite Rotatable Design (CCRD) of Response Surface Methodology (RSM) while the response was percentage conversion. The suggested model and the process variables were significant as depicted by their p-values. The model validation showed that the optimal conversions, 87.3% and 76.7%, obtained for soybean and castor oil modified resins respectively, at a reaction temperature of 247.5 °C, reaction time of 155.3mins and 46.2 g of phthalic anhydride conformed wholly with the actual conversions, 84.7% and 75.2%, obtained respectively at the same conditions. Therefore, it can be deduced that soybean oil modified resins have better yield and offered more desirable features.

The comparison of ion concentrations, pH index, and conductivity in distilled and ground water after exposure to low-temperature plasma formed by barrier and bubble discharges is performed. It has been found that in the case of groundwater, the best performance for the production of NO3− anions is provided by the discharge inside the gas bubbles. For distilled water, the barrier discharge in air, followed by saturation of water with plasma products, is the most suitable from this point of view. In both treatments, the maximum energy input into the stock solution is ensured. After 10 min treatment of ground water, the pH index increases and then it decreases. The obtained numerical indicators make it possible to understand in which tasks the indicated treatment modes should be used, their comparative advantages, and disadvantages. From the point of view of energy consumption for obtaining approximately equal (in order of magnitude) amounts of NO3− anions, both types of discharge treatment are suitable. The research results point to a fairly simple way to convert salts (calcium carbonates) from an insoluble form to soluble one. Namely, when interacting with NO3− anions, insoluble carbonates pass into soluble nitrates.

In this paper, the three-dimensional bowl surface was obtained by reasonably planning the radial heating path by taking the laser as the heat source and the stainless steel composite plate (06Cr19Ni10/1Cr17Mn6Ni5N/06Cr19Ni10) as the research object, and the forming process of the three-dimensional bowl surface was studied. It was found that the target surface bending forming obtained by inside-outside symmetric scanning strategy (strategy d) had the highest accuracy. The plate deformation increased with the increase of laser power (P), increased then decreased with the increase of heating line length (L), and decreased with the increase of scanning speed (V). Moreover, the deformation was approximately linear with the number of repeated heating (N), with the optimal process conditions of P = 500 W, V = 10 mm/s, L = 20 mm, N = 7. A three-dimensional thermodynamic coupling model of a three-layer composite plate was established and verified experimentally. [ABSTRACT FROM AUTHOR]

Several studies have searched for new antigens to produce pneumococcal vaccines that are more effective and could provide broader coverage, given the great number of serotypes causing pneumococcal diseases. One of the promising subunit vaccine candidates is untagged recombinant pneumococcal surface protein A (PspA4Pro), obtainable in high quantities using recombinant Escherichia coli as a microbial factory. However, lipopolysaccharides (LPS) present in E. coli cell extracts must be removed, in order to obtain the target protein at the required purity, which makes the downstream process more complex and expensive. Endotoxin-free E. coli strains, which synthesize a nontoxic mutant LPS, may offer a cost-effective alternative way to produce recombinant proteins for application as therapeutics. This paper presents an investigation of PspA4Pro production employing the endotoxin-free recombinant strain ClearColi® BL21(DE3) with different media (defined, auto-induction, and other complex media), temperatures (27, 32, and 37 °C), and inducers. In comparison to conventional E. coli cells in a defined medium, ClearColi presented similar PspA4Pro yields, with lower productivities. Complex medium formulations supplemented with salts favored PspA4Pro yields, titers, and ClearColi growth rates. Induction with isopropyl-β-d-thiogalactopyranoside (0.5 mM) and lactose (2.5 g/L) together in a defined medium at 32 °C, which appeared to be a promising cultivation strategy, was reproduced in 5 L bioreactor culture, leading to a yield of 146.0 mg PspA4Pro/g dry cell weight. After purification, the cell extract generated from ClearColi led to 98% purity PspA4Pro, which maintained secondary structure and biological function. ClearColi is a potential host for industrial recombinant protein production. Key points: • ClearColi can produce as much PspA4Pro as conventional E. coli BL21(DE3) cells. • 10.5 g PspA4Pro produced in ClearColi bioreactor culture using a defined medium. • Functional PspA4Pro (98% of purity) was obtained in ClearColi bioreactor culture. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To develop a novel material that can be used as a substitute for phenol foam, tannins are used instead of the phenol components to prepare tannin-based foams at room temperature. The impact of the blowing agent content ( n-pentane and diethyl ether), crosslinking agent(formaldehyde and glyoxal), and furfuryl alcohol on the density, microstructure, heat preservation, flame retardant property, and mechanical properties were examined and the processing conditions were optimized. The results show that the density of tannin-based foam was controllable in the range of 70-330 kg.m -3 by adjusting the experimental conditions. The pore sizes of these tannin-based foams were in the range of 96-3 615 µm. The pore size decreases with increased density and exhibits a linear relationship. In addition, the density of tannin-based foams decreased with an increase in foaming agent and furfuryl alcohol. The influence of different cross-linking agents, formaldehyde, and glyoxal, were not significant. Under different content of foaming and cross-linking agents, the compression strength and density of the solid tannin-based foam material were found to be positively correlated. The effect of furfuryl alcohol on mechanical properties is caused by the density and the cross-linking degree of the foam. Compared with traditional phenolic foam, the tannin-based foam has excellent flame resistance, thermal insulation, and mechanical properties. Tannin-based foam is a new and green foam material with high application potential. [ABSTRACT FROM AUTHOR]

Optimization of process parameters for the regeneration of used mobil oil by acid/clay method using sulphuric acid as washing agent was successfully carried out. Used mobil oil was characterized before and after regeneration to determine the changes in the physicochemical properties of the oils. The viscosity, flash point and fire point of the oil increased after regeneration while the specific gravity and sulphur content decreased. The Atomic Absorption Spectrometry (AAS) carried out revealed the presence of eight different metals in the fresh mobil whose concentration increased during use but reduced after regeneration. The FTIR instrumentation analysis revealed that the used mobil oil has high concentration of some ester groups, aromatic materials, glycol and sulphur oxidation products while the proportion of these materials plunged significantly after treatment. Changes in the process conditions like acid concentration, settling time and bleaching temperature affected the effectiveness of the regeneration process by affecting the desired changes in the physicochemical properties. The process parameters were optimized using Central Composite Rotatable Design (CCRD) of Response Surface Methodology (RSM), with the aid of design expert. The design, which use purity as the response of the experiment, considered three independent factors of acid concentration, settling time and bleaching temperature; and the effects of these factors on the response are significant since their P-values are less than 0.05. An optimum theoretical purity of 0.86 was obtained at 6.5mol/lit acid concentration, 5.5hours settling time and 95.5 °C bleaching temperature, which agreed excellently with 0.85 actual purity obtained at the same conditions. Therefore, the regenerated mobil oil at these optimal conditions is capable of meeting commercial expectations.

Hot embossing has been widely used in fabricating microlens arrays because of its low cost, high efficiency, and high quality. The process parameters such as molding temperature, molding pressure, and holding temperature affect the microlens array's replication quality. This work selected the stainless steel S136H tool steel as the mold material to process an aspheric microlens array structure through ultra-precision milling. Polymethyl methacrylate (PMMA) microlens arrays with different surface replication were prepared by controlling the molding temperature, molding pressure, and holding temperature. By analyzing the surface quality, contour replication, and optical imaging of hot-embossed samples, the optimal molding temperature of PMMA for optimal replication of aspheric lens arrays was determined as 130 °C. Besides, the internal elastic recovery of PMMA affected the dimensional accuracy and optical performance of the lens. The results showed that, at the molding pressure of 400 N and the holding temperature of 60 °C, the surface defects were eliminated, and the aspheric lens array had perfect replication with a profile deviation of only 4 μm. The aspheric microlens array with good quality was eventually achieved by these optimal process parameters, which provides a foundation for producing aspheric microlens arrays in a low-cost and high-efficiency way. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The properties of foamed glass are substantially determined by interaction between glass and foaming agent during sintering process. Knowing the foaming mechanism and the influence of process conditions will help to reduce the defects of foamed glass. In this research, the TG–DSC–DTG thermal analysis was used to investigate the thermal behavior of waste glass, graphite (foaming agent) and their mixture to explore the foaming mechanism, as well as the effect of process conditions on the properties of foamed glass was discussed. Results indicate four stages in the weight-loss can be distinguished during the heating process: (I) 25–300 °C, (II) 300–450 °C, (III) 450–748 °C and (IV) above 748 °C. The (IV) stage between 748 and 909 °C is the main stage of foaming. Foaming temperature, holding time, foaming agent content and milling time have difference effects on the properties of foamed glass. Foaming temperature and holding time mainly affect the distribution of pores and average aperture respectively. The thickness of the pore wall and density of the foam are determined by foaming agent content, while milling time can control the quality of foamed glass by affecting the particle size of the mixture. The foamed glass showed the best properties when the mixture with 2 wt% foaming agent was sintered at 880 °C for 10 min after milling for 2.5 h. [ABSTRACT FROM AUTHOR]

In a batch electro-electrodialysis (EED), sodium sulphate solution with an initial concentration of 80.90 g/dm3 was converted to obtain solutions of sodium hydroxide (13.96%) and sulphuric acid (10.15%) and a dialysate (3.23 g/dm3 of sulphate ions). Changes in the EED process′ performance (temperature, cell voltage, concentrations, energy consumption) with an increasing conversion degree of salt are presented. Based on the presented results of the batch experiment, conditions necessary to run the process continuously are discussed. A single pass method is inapplicable due to excessive heating of the electro-electrodialyser. A cascade method enables interstage cooling of the solutions, providing temperatures suitable for ion-exchange membranes to work. Increasing the number of stages in the cascade reduces both the number of electro-electrodialysers and specific electric energy consumption, providing the same production capacity. However, this increases the investment cost.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Small-size cutting inserts for assembly cutters are widely used to manufacture a variety of parts for the aerospace, automotive and mechanical engineering industries. Due to their high hardness and chemical stability, cutting Al2O3-TiC ceramics significantly outperform hard alloys in machining heat-resistant and difficult-to-machine materials. However, grinding on CNC machines, the most common technology for manufacturing ceramic inserts, is associated with numerous issues when it comes to manufacturing small-size cutting inserts. For example, high cutting forces and high grinding wheel wear rates cause a rapid loss of dimensional accuracy and deterioration of the quality of the surface being machined, while the interference of the grinding wheel with the surface being treated imposes serious limitations on the geometry of the small-size ceramic inserts to be grinded. Here we show that Wire Electrical Discharge Machining (WEDM), which is a contactless and, thus, a more flexible method in terms of the size and geometrical properties of a workpiece to be machined, can be used as a replacement for grinding operations in machining small ceramic inserts. A composite of 70% aluminum oxide and 30% titanium carbide was chosen as a ceramic material because a further increase in the TiC fraction causes a marked decrease in wear resistance, while its decrease results in an undesirable loss of electrical conductivity. While in order to replace grinding with WEDM, WEDM has to be stable in the sense of occurring without frequent wire breakages, achieving WEDM stability is not an easy task due to the low electrical conductivity of Al2O3-TiC ceramics and high operational temperatures, which promote the diffusion of dielectric and electrode products in the surface layer of the cutting inserts being machined. These factors may lower the quality of the final product due to damage to the insert surface, marked increases in the roughness RA and in diffusion in the surface layer, which increases the friction coefficient and, hence, reduces the life of the manufactured cutting inserts. We have increased stability of the WEDM process by identifying and applying rational process conditions that lead to a reduced, by a factor of 2.63, roughness Ra and also a reduced, by a factor of 1.3, depth of craters. Performing a chemical and structural analysis, we found that the application of high energies combined with an increasing interelectrode gap (IG) (technological parameter SSol, a complex indicator that determines the speed of the wire electrode depending on the number of pulses per unit of time and the IG size, is set at 80, EDM3 technology) causes increased surface damage and contamination, while a small IG (SSol = 45, EDM1 technology) reduces the material removal rate due to contamination of the working zone between the surface being machined and the electrodes. After reducing the IG by lowering SSol from 80 to 45, the roughness Ra of 0.344 µm was achieved, which allows for replacing grinding operations with WEDM in machining hardening chamfers, front surfaces and, to a lesser degree, the rear and support surfaces of cutting inserts. In this case, when the IG is reduced to SSol = 45, the electroerosion products in the dielectric promote local breakdowns, which in turn produce a large number of deep craters which adversely affect the performance of cutting inserts. However, we found that a slight increase in SSol from 45 to 55 (EDM3 technology) significantly reduces the number of craters and lowers their depth from 50 μm to 37 μm. Although in this case the roughness grows to 0.534 μm due to increased discharge energy, the improved flushing of the IG and the reduced occurrence of local high-temperature breakdowns—evidenced by a decrease in the depth and number of deep craters formed due to current localization during short circuits—significantly reduced contamination of the surface layer and the crater formation rate. Therefore, WEDM can be recommended for use in machining reinforcing chamfers and, to a lesser degree, front surfaces. These considerations lead us to conclude that WEDM is a viable alternative to grinding in machining Al2O3-TiC ceramic cutting inserts of a small size and a complex shape, and that its application to manufacturing cutting inserts from poorly conductive cutting ceramics should be studied further.

The hydroisomerization of pure n-pentane over H-mordenite supported Pt-catalyst was investigated in a fixed bed reactor by changing reaction parameters such as temperature, pressure, and WHSV, as well as the H2/HC ratio. The maximum yield of isopentane over Pt/mordenite catalyst was achieved at 220 °C and a relatively low reaction pressure. To address the effect of feed composition on the catalytic performance of the samples, the catalysts were assessed for activity and selectivity in the isomerization of a mixture consisting of n-pentane (70 wt.%) and isopentane (30 wt.%) at 220 °C. The effects of pressure, WHSV, and H2/HC ratio on the catalyst performance were also studied using binary mixtures of the pentane isomers as a feedstock. It was observed that an effect of WHSV and H2/HC on the catalytic performance was similar to its behavior in pure n-pentane isomerization, while the conversion of n-pentane in the binary mixture showed a different trend and had a minimum value at 1.5 bar. It could be due to the presence of isopentane in feed and adsorption phenomenon of binary mixture on mordenite-supported catalyst.

This paper presents a modeling approach implemented to consider the effects of the process parameters of Abrasive Jet Machining (AJM), namely applied pressure (Pr), standoff distance (SoD), nozzle diameter (dn) and particle grain size (dg) on machining performance. In particular, a previously reported model of the AJM was adapted to improve its capability to predict material removal rate (MRR) more accurately. In order to validate the developed model experimentally and at the same time to examine the influence of the machining conditions on the MRR, a series of drilling tests have been carried out on glass workpieces using sand as an abrasive powder. After each cutting trial, the MRR was quantified which enabled characterizing the influence of the applied process parameters on the machining performance in terms of resultant MRR. In addition, the experimental results were compared with those obtained by the proposed model, where a relatively acceptable agreement between both results was achieved with an average error of 39%. Also, the experimental results have revealed that MRR is highly dependent on the kinetic energy of the abrasive particles and the applied pressure was found to be the most significant parameter that dominated the material removal rate

Hot embossing has been widely used in fabricating microlens arrays because of its low cost, high efficiency, and high quality. The process parameters such as molding temperature, molding pressure, and holding temperature affect the microlens array’s replication quality. This work selected the stainless steel S136H tool steel as the mold material to process an aspheric microlens array structure through ultra-precision milling. Polymethyl methacrylate (PMMA) microlens arrays with different surface replication were prepared by controlling the molding temperature, molding pressure, and holding temperature. By analyzing the surface quality, contour replication, and optical imaging of hot-embossed samples, the optimal molding temperature of PMMA for optimal replication of aspheric lens arrays was determined as 130 °C. Besides, the internal elastic recovery of PMMA affected the dimensional accuracy and optical performance of the lens. The results showed that, at the molding pressure of 400 N and the holding temperature of 60 °C, the surface defects were eliminated, and the aspheric lens array had perfect replication with a profile deviation of only 4 μm. The aspheric microlens array with good quality was eventually achieved by these optimal process parameters, which provides a foundation for producing aspheric microlens arrays in a low-cost and high-efficiency way.

Hydrothermal carbonization (HTC) reactor systems used to convert wet organic wastes into value-added hydrochar are generally classified in the literature as liquid water-based (HTC) or vapor-based (VTC). However, the distinction between the two is often ambiguous. In this paper, we present a methodological approach to analyze process conditions for hydrothermal systems. First, we theoretically developed models for predicting reactor pressure, volume fraction of liquid water and water distribution between phases as a function of temperature. The reactor pressure model predicted the measured pressure reasonably well. We also demonstrated the importance of predicting the condition at which the reactor system enters the subcooled compression liquid region to avoid the danger of explosion. To help understand water–feedstock interactions, we defined a new solid content parameter %S(T) based on the liquid water in physical contact with feedstock, which changes with temperature due to changes in the water distribution. Using these models, we then compared the process conditions of seven different HTC/VTC cases reported in the literature. This study illustrates that a large range of conditions need to be considered before applying the label VTC or HTC. These tools can help in designing experiments to compare systems and understand results in future HTC research.

Microwave sintering process was employed to agglomerate ferromanganese alloy powders. The effects of sintering temperature, holding time and particle size composition on the properties and microstructure of sintering products were investigated. The results was shown that increasing sintering temperature or holding time appropriately is beneficial to increase the compressive strength and volume density. SEM and EDAX analysis shows that the liquid phase formed below the melting point in the sintering process, which leads to densification. XRD patterns indicate that the main reaction during microwave sintering is the decarbonization and carburization of iron carbide phase. The experiment demonstrate that the optimum microwave sintering process condition is 1150°C, 10 min and 50% content of the powders with the size of –75 μm

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Graphical abstract Highlights • Process conditions have a major effect on the competition between ethylene oligomerisation and ethylene polymerisation. • Optimisation of process conditions drastically reduced solids that were obtained from sulfur-based ligands. • Catalysts that were overlooked due to high solids formation can be improved by simply optimising the process conditions. Abstract Sulfur-based bidentate ligands are active in Cr-catalysed selective ethylene oligomerisation but generally produce large amounts of solids. Through a systematic process condition optimisation study, the amount of solids formed with two P,S-bidentate ligands was reduced from 88% and 57% to 13% and 6% respectively, while maintaining reasonable oligomerisation activities and achieving high liquid product selectivities (>50% 1-octene and >75% 1-hexene and 1-octene combined). The selective suppression of solids formation indicated that ethylene oligomerisation and polymerisation reactions are possibly facilitated by different catalytic species. [ABSTRACT FROM AUTHOR]

Microwave sintering process was employed to agglomerate ferromanganese alloy powders. The effects of sintering temperature, holding time and particle size composition on the properties and microstructure of sintering products were investigated. The results was shown that increasing sintering temperature or holding time appropriately is beneficial to increase the compressive strength and volume density. SEM and EDAX analysis shows that the liquid phase formed below the melting point in the sintering process, which leads to densification. XRD patterns indicate that the main reaction during microwave sintering is the decarbonization and carburization of iron carbide phase. The experiment demonstrate that the optimum microwave sintering process condition is 1150°C, 10 min and 50% content of the powders with the size of -75 μm. [ABSTRACT FROM AUTHOR]

Electrospinning is a simple and highly versatile method for generating ultrathin fibers (mainly polymers) with diameters ranging from a few micrometres to tens of nanometres. This technique has attracted tremendous recent interest in both academia and industry, owing to its unique ability to produce ultrafine fibers of different materials in various fibrous assemblies. Electrospinning is a process that uses an electric potential to overcome the surface tension of a solution to produce an ultra-fine jet, which elongates, thins and solidifies as it travels through the electric field to a collector.. In this research, we studied the effect of conditions of the cabin “specifically humidity” on the diameter of nanofibers manufactured by electrospinning. We used Polyvinyl alcohol (PVA) polymeric solution with weight concentration of 10%, voltage 20 kv, under different values of relative humidity. Fiber morphology and fiber diameter were determined using scanning electron microscope, and measuring the fiber diameter by using image j program. It was found that the diameter of the fibers increased with increasing the relative humidity within our studying area .

The present study was focused on establishing guidelines for successful friction stir welding of Al alloys and Cu lap joints. Detailed investigations in respect to tool geometry, tool material, work-piece material, welding parameters, stacking sequence, and heat sink were carried out. The soundness of welded joints was tested through microscopic analysis and the lap shear test. The results revealed that the tungsten carbide (WC) tool with square-pin produced sound joints in terms of minimized defects and high strength. Further, the use of heat sink proved as an important pre-requisite when the stacking sequence was inversed (i.e., Cu-Al), and this stacking configuration in comparison with the Al-Cu stacking yielded weaker joints. The influence of the tool welding speed (F, mm/min) was found to depend upon the tool material. A range of tool welding speed (23.5−37.5 mm/min) worked well for the WC tool. However, only two values of welding speed (30 mm/min and 37 mm/min) were observed to be conducive when the tool material was HSCo (high-speed cobalt)-steel. Finally, it was concluded to employ the WC tool with square-pin, a welding speed of 30 mm/min, the rotational speed (S, rpm) of 1500 mm/min, and Al-Cu stacking sequence to successfully process the Al/Cu lap joints.