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In this study, solid formaldehyde, benzoguanamine and butanol were used to synthesize butylated benzo-amino resin by one-step-two-stage method.

This research first examined the influence of solid formaldehyde content on the hydroxymethylation phase. Subsequently, the effects of butanol content, etherification time and hydrochloric acid content on the formation of benzo-amino resin during the etherification stage were studied in detail. In addition, the reaction process was further analyzed through interval sampling withdrawing during the hydroxymethylation and etherification stages. Finally, the synthesized benzo-amino resins were used in the production of high solid content polyester and acrylic coatings and the properties of that were also evaluated.

Based on the experimental findings, the authors have successfully determined the optimal process conditions for the one-step-two-stage method in this study. The hydroxymethylation stage demonstrated the most favorable outcomes at a reaction temperature of 60°C and a pH of 8.5. Similarly, for the etherification stage, the optimal conditions were achieved at a temperature of 45°C and a pH of 4.5. Furthermore, the investigation revealed that a ratio of benzoguanamine to solid formaldehyde to n-butanol, specifically at 1:5.2:15, produced the best results. The performance of the resulting etherified benzo-amino resin was thoroughly evaluated in high solid content coatings, and it exhibited promising characteristics. Notably, there was a significant enhancement in the water resistance, solvent resistance and glossiness of canned iron printing varnish coatings.

Amino resin, a versatile chemical compound widely used in various industries, presents challenges in terms of sustainability and operational efficiency when synthesized using conventional methods, primarily relying on a 37% formaldehyde solution. To address these challenges, the authors propose a novel approach in this study that combines the advantages of the solid formaldehyde with a two-stage catalytic one-step synthesis process. The primary objective of this research is to minimize the environmental impact associated with amino resin synthesis, optimize resource utilization and enhance the economic feasibility for its industrial implementation. By adopting this alternative approach, the authors aim to contribute toward a more sustainable and efficient production of amino resin.

Soy beverage is becoming more and more popular because it is touted as a healthy food containing useful phytochemicals and is free from lactose and cholesterol. The purpose of this paper is to optimize the spray drying process parameters for obtaining soy beverage powder with good reconstitution and handling properties.

Pre-concentrated soy beverage was dried in a laboratory model spray dryer, and the effects of inlet air temperature (180-220°C), feed rate (20-40 ml/min) and feed solid content (15-25 per cent) on some physical parameters and reconstitution properties (wettability and dispersibility) of spray-dried soy beverage powders were investigated. Second order polynomial response surface model was selected for the analysis of data and optimization of the process.

Spray drying of soy beverage at different processing conditions resulted in powders with particle size (volume mean diameter) in the range of 86 to 156 µm. Dispersibility and wetting time of the spray-dried soy beverage powders was found to be in the range of 56 to 78 per cent and 30 to 90 s respectively, under various drying conditions. Inlet air temperature was found to be the main factor affecting most of the quality parameters, followed by solid content of the feed. Temperature significantly affected the wettability, dispersibility, colour parameters, particle size and flowability of the powder at p ≤ 0.01. Lower temperature and higher feed solid content produced bigger-sized powder particles with better handling properties in terms of flowability and cohesiveness. A moderate inlet air temperature (196°C), higher feed solid content (24 per cent) and lower feed rate (27 ml/min) were found suitable for drying of soy beverage.

The study implied the possibility of producing powder from soy beverage using the spray-drying method and optimized drying conditions for obtaining soy beverage powder with good reconstitution properties.

The finding of this study demonstrated for the first time how the inlet air temperature, feed solid content and feed rate during spray-drying influenced different quality parameters of soy beverage powder. Further, an optimized drying condition has been identified.

The purpose of this paper is to carry out a comprehensive experimental investigation into the role of screen and conductive carbon material formulation on line conductivity and printing capability in the screen printing process, to provide design knowledge and further understanding of the screen printing for printed carbon.

A full factorial experiment was carried out where six carbon materials were printed through ten screens to a polyester substrate under a set of standard conditions.

Material characterization showed that viscosity and the corresponding viscous and elastic material modulli increased with solids content and that the elastic properties at low shear are significant. The solids carbon content materials were unable to produce the minimum printable line features possible with the low carbon materials. Increasing the solids contents reduced the final cured line resistance, reduced the printed line width, increased the film thickness, increased the cross sectional area and reduced the material resistivity. Material resistivities were around 700 to 950 μΩcm were obtained in the printed lines.

Lower material resistivities were obtained with higher solids materials and it is postulated that the increased visco‐elastic nature of the solids content materials, play a role in determining the microscopic structure of the cured film through alignment of the carbon graphite platelets.

A dataset which allows material, screen and print characteristics has been created allowing process optimization and formulation development to be accelerated.

The work provides insight into the role of material properties and process settings on the electrical and physical characteristics of printed carbon.

Evaluations of food aid products such as corn soy blend (CSB) suggest that higher nutrient-dense weaning foods are needed. CSB at 20 per cent solids was suggested, but it is too thick for weaning use. The purpose of this paper is to examine if high or low pressure extrusion or a change from corn to sorghum could reduce viscosity without major sensory changes compared to CSB, a widely used fortified blended food (FBF).

A 2×2 factorial design of grain (corn or sorghum) and extrusion pressure (low or high) was used to produce fortified extruded CSB and sorghum soy blend (SSB) that match new nutritional recommendations at 20 per cent solids. A control CSB sample was also produced. Porridge was made and a descriptive panel measured sensory properties and a Bostwick Consistometer determined viscosity.

Control CSB was thicker, lumpier, and stickier than the extruded samples. Sorghum samples had more sorghum flavour and corn samples had more corn flavour, but generally other flavour characteristics differed only slightly from the control product. None of the samples were as thin as recommended for infant swallowing, but the extruded sorghum samples were less viscous than other samples.

Nutrient-dense FBFs at high solids content have been recommended but not yet well tested. This paper provides a sensory examination of high solids FBFs with the potential for use as supplementary foods for infants and children.

Automotive coating materials are very important items for this industry. However, their performance is limited by the use of excessive amounts of solvents in their formulations, whereas the emission of volatile organic solvents is against the widely ascending principle of green chemistry. Thus, this study aims to overcome this global problem to save the environment without affecting the properties and performance of the coating.

High solid content paint formulation for automotive applications has been designed with low amount of volatile organic solvents with the aid of a functionalized hyperbranched modifier.

It was found that the presence of a hyperbranched additive allows a high solid content to be designed and facilitate the processing, which indicates its liability to compensate the role played by excessive solvents amounts. In addition, the mechanical properties and physical characteristics of the modified coatings showed outstanding performance and preservation of clarity in comparison with the commercial counterparts.

A high solid content coating with facile processing and improved performance leads to cheaper price beside the positive impact on the environment considering the limited emission of volatile organic contents.

Limitation of the used volatile organic compounds in any industry helps to save the health of humans and keep the environment unaffected.

The use of functionalized hyperbranched additive to automotive coatings is a very promising additive for automotive coatings with optimized characteristics.

The interaction between the silver powder and organic vehicle largely determines the rheological behavior of silver conductive paste. This study aims to prepare silver conductive paste with an organic vehicle system consisting of ethyl cellulose (EC) and terpineol/butyl carbitol acetate solvent mixtures. The study also aims to measure the rheological behaviors of the silver conductive pastes with different solvent mixtures, EC molecular weights and silver content, to investigate the interaction among the polymer, solvent and silver powder and determine the main factors affecting the thixotropic index and maximum silver content.

The rheological behaviors of silver conductive pastes with different solvent mixtures, EC molecular weights and silver content were investigated using viscometer.

The shear thinning became significant with increasing EC molecular weight. The EC solvation with higher molecular weight in solvent is better than that of EC with lower molecular weight. This leads to a stronger interaction between the silver powder and EC with higher molecular weight and consequently good silver particle dispersion. The relative viscosity of silver conductive paste at 10 s⁻¹ increases significantly with increasing silver content, but the relative viscosity at 100 s⁻¹ is much less sensitive to the silver content. The viscosities at low and high shear rate can be increased by increasing the silver content and EC molecular weight, respectively.

The interaction among the polymer, solvent and silver powder was investigated for the silver paste with high solid content. The main factors affecting the viscosities at high and low shear rates, thixotropic index and maximum silver content were determined.

This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors such as hydraulic retention time and hydraulic loading rate and its influence on the treatment dynamics. Because of intermittent feeding mode of VFCW systems and variation in its loading, its hydraulic behaviour is highly variable and need to be understood to optimize its treatment performance.

Tracer test were carried out using bromide ion with varying hydraulic loading rates (HLR) of 6.82 cm/d, 9.09 cm/d and 11.40 cm/d (i.e. equivalent to 75 L/d, 100L/d and 125 L/d). Tracer data is then analysed using the Residence Time Distribution (RTD) method.

RTD analysis showed that the increase in HLR increases the average hydraulic retention time (HRT). Subsequently, the increase in HLR results in a lower recovery of effluent, resulting in poor productivity in treatment. The study also showed that the removal of nitrogen and organic matter improved with increasing HRT. However, observations show no correlation between HRT and total solids removal.

A performance evaluation method (by tracer) is proposed to understand the hydraulics of flow in constructed wetlands, which has not been widely studied. Additionally, the dynamics of treatment in VFCWs treating septage may also be revealed by the tracer method. The study can be applied to any constructed wetlands designed for treatment of wastewater, septage or sludge.

The rheological properties of coating suspensions containing a blend of clay and CaCO3 as a pigment have been evaluated at 22°C, using a rheometer with shear rates from 0.5 to 100rpm. The state of dispersion of the pigment, the structure viscosity of the suspension as a result of pigment‐pigment or pigment‐binder interactions, and its behaviour by changing the solid content and ionic strength, were limited from the examination of the flow curves. The flow parameters for each suspension were calculated. The results showed that changes in solid content and ionic strength by the addition of divalent simple electrolyte (CaCl2) and pH level have a more profound effect on the flow parameters than that obtained by the addition of monovalent simple electrolyte (NaCl) or polyelectrolyte soluble polymers (CMC) with different degrees of substitution. The type of acid used to adjust the pH of the suspension also has a great influence on the flow parameters.

This paper aims to focus on the liquefaction of soybean protein to obtain a homogeneous protein solution with a high solid/protein content but low viscosity, which may improve the bond properties and technological applicability of soybean protein adhesive.

The liquefactions of soybean protein in the presence of various amounts of sodium sulphite, urea and sodium dodecyl sulphate (SDS) are investigated, and their effects on the main properties of liquefied soybean protein and soybean protein adhesives are characterized by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), viscosity tracing and plywood evaluation. Meanwhile, the applicability of soybean protein adhesive composed of liquefied protein for particleboard is also investigated.

Soybean protein can be effectively liquefied to form a homogeneous protein solution with a soybean protein content of 25 per cent and viscosity as low as 772 mPa.s; the addition of sodium sulphite, urea and SDS are beneficial for the liquefaction of soybean protein and have important effects on the technological applicability and water resistance of the obtained adhesive. The optimal liquefying technology of soybean protein is obtained in the presence of 1.5 Wt.% of sodium sulphite, 5 Wt.% of urea, 1.5 Wt.% of SDS and 3 Wt.% of sodium hydroxide. The optimal soybean protein adhesive has the desired water resistance in terms of the boiling-dry-boiling aged wet bond strength, which is up to 1.08 MPa higher than the required value (0.98 MPa) for structural use according to the commercial standard JIS K6806-2003. The optimal liquefied protein has the great potential to prepare particleboard.

The protein content of liquefied soybean protein is expected to further increase from 25 to 40 Wt.% or even higher to further reduce the hot-pressing cycle or energy consumption of wood composites bonded by soybean protein adhesives.

The soybean protein adhesive composed of optimal liquefied protein has potential use in the manufacturing of structural-use plywood and has comparable applicability as a commercial urea-formaldehyde resin for the manufacturing of common particleboard.

Soybean protein adhesive is an environmentally safe bio-adhesive that does not lead to the release of toxic formaldehyde, and the renewable and abundant soybean protein can be used with higher value added by the application as wood adhesive.

A novel liquefaction approach of soybean protein is proposed, and the soybean protein adhesive based on the liquefied protein is obtained with good technological applicability and desired bond properties that extend the applications of the soybean protein adhesive from interior plywood to particleboard and exterior or structural plywood.

The purpose of this study was to determine differences in taste-related and bioactive compounds of organically (OR) and conventionally (CONV) cultivated commercially produced strawberries (Fragaria × ananassa Duch.). Addresses the question if the consumers buying OR strawberries are likely to purchase fruits with better taste and richer in bioactive compounds than those buying CONV fruits.

Only information commonly available to the consumers [cultivar, quality class, product origin (country) and eco-labelling], was considered in selecting experimental material. “Polka” strawberries from 14 farms (7 OR and 7 CONV) from South Estonia were used for analyses.

No evidence was found that OR strawberries contain more bioactive compounds or have higher soluble solids content and titratable acids ratio (associated with better taste) compared to CONV strawberries. There were significant differences in content of total phenolics, anthocyanins, ascorbic acid, vitamin E, total antioxidant capacity, titratable acids and soluble solids between strawberries from individual farms irrespective of cultivation system.

Our study was limited to strawberry “Polka” and some other cultivars might response differently to production systems.

Consumers get information that by choosing an organic product in the marketplace, it is not guaranteed that this product has higher content of bioactive compounds.

Comparative studies of organic and conventional products are preferably performed with products grown at the same location with the same amount of nutrients etc. However, information of production site’s microclimate, soil texture or the amount of plant available nutrients is never available to the consumers. Therefore, our consumer-oriented approach might be valuable.