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This paper aims to study the direct synthesis of imino methyl ether amino resin using commercially available formaldehyde, melamine and methanol through one-step two-stage catalysis.

Initially, melamine undergoes a reaction with formaldehyde to form hydroxylmethylation melamine in a basic setting. Subsequently, hydrochloric acid is incorporated to facilitate the etherification process. The study delves into the impact of various factors during the etherification phase, including the quantity of methanol, the temperature at which etherification occurs, the number of etherification cycles and the amount of catalyst used, on the synthesis of imino methyl-etherified amino resins. Ultimately, the most favorable conditions for etherification are identified through comparative analysis to evaluate the resulting synthesized products.

The methyl-etherified amino resin, characterized by a stable structure and consistent performance, was efficiently synthesized through a one-step, two-stage catalytic process. Optimal conditions for the etherification stage were determined to be a reaction temperature of 35°C, a melamine to methanol ratio of 1:24 and an addition of hydrochloric acid ranging from 2.2 mL to 2.5 mL. Remarkably, the resulting resin notably enhanced the water resistance, salt resistance and gloss of the canned iron printing varnish coatings.

Amino resins, known for their broad applications across numerous industries, face sustainability and operational efficiency hurdles when produced through traditional methods, which predominantly involve the use of a 37% formaldehyde solution. To tackle these issues, our research introduces an innovative method that add 37% formaldehyde to facilitate industrial production. The use of 37% liquid formaldehyde in this paper has two benefits: first, it is convenient for industrial application and production; Second, it is convenient to provide mild reaction conditions at lower concentrations because the amino group is relatively active, which is convenient for the preservation of the amino group and integrates it with a one-step, two-stage catalytic process. The primary objective of our study is threefold: to reduce the environmental footprint of amino resin synthesis, to optimize the use of resources and to improve the economic viability for its large-scale production. By employing this new strategy, we try to provide a more sustainable and efficient manufacturing process for amino resins.

The objective was to investigate the utility of cottonseed oil (CSO) as a raw material for the synthesis of CSO water-based alkyd resin. The synthesis involved the polymerization of CSO, trimethylolpropane, phthalic anhydride (PA) and trimellitic anhydride (TMA). The prepared resin coating material was subsequently applied to the surface of steel structure material.

This study aimed to synthesize water-based alkyd resins using CSO. Therefore, the alkyd resin was introduced with TMA containing carboxyl groups and neutralized with triethylamine (TEA) to form a water-soluble salt. Then, the esterification kinetics of CSO water-based alkyd resin were investigated, and finally, the basic properties of CSO water-based alkyd resin coating were evaluated.

It was demonstrated that CSO water-based alkyd resin exhibited excellent water solubility and that the esterification kinetic of the synthesis reaction could be described by a second-order reaction. The coating properties of the material were investigated and found to have good basic properties, with 40% resin addition having the best corrosion resistance. Consequently, it could be effectively applied to the surface of steel structural materials.

This study not only met the requirement of environmentally friendly development but also expanded the application of CSO through the synthesis of CSO water-based alkyd resin via alcoholysis. Compared to fatty acid process, the alcoholysis reduced the need for fatty acid pre-extraction, simplifying the alkyd resin synthesis process. Thus, economic costs are effectively reduced.

Bisphenol A (BPA) is a compound commonly used in the production of plastic bottles and containers, where it is used as a plasticizer and can migrate into food. Its intake may impair the functioning of endocrine glands and have a negative impact on the health of human, especially infants. Because it is also found in baby bottles. Generally BPA can enter the body through daily, cumulative and long-term consumption of various foods. The purpose of this study is to investigate the level of BPA and its migration through some food containers and bottles. It also explains the potential risks associated with its consumption.

In this study, some of the research conducted in this field has been used by searching in various Web databases, including ScienceDirect, Scopus and PubMed. Therefore, this study provides an overview of the migration of BPA from different packages and compares the obtained values with standard ranges.

Most studies showed samples below the reference value. However, the use of containers made with BPA should be controlled and government policies should be implemented to eliminate or reduce the use of these containers.

This paper collects evidence of migration of BPA to some foods through bottles and food containers.

Environmental pollution has increased as a result of modern settlements' expanding demand and rapid population growth. In Ebonyi State, Nigeria, quarrying is one of the activities that has an impact on the environment and ecosystem. The aim of the study is to assess stream water’s quality in order to ascertain how quarry operations affect the streams’ water quality. The present study investigated the environmental impact of quarrying on the physicochemical properties of surface water in Ebonyi State, Nigeria.

A total of 288 surface water samples were taken in 2018, 2019 and 2020 from quarry locations and a Control location for the determination of physicochemical properties and heavy metal contents using standard analytical methods. Datasets were analysed using Fisher’s significance least difference (F-LSD) at the 0.05 probability level.

This study discovered that surface waters around quarries are severely polluted, according to the results of the physico-chemical and heavy metal contents of the surface waters. Most of the physical and chemical properties of the water downstream of the Ishiagu, Umuoghara and Ngbo did not meet World Health Organisation (WHO) standards, such as colour and pH. The heavy metal levels in the Ishiagu, Umuoghara and Ngbo streams were above WHO criteria for Pb, Cd and Fe. The results point to the obvious conclusion, without prejudice to other unexplained factors that the pollution is most likely the result of quarry contamination. Strict measures should be taken to regularly monitor the water quality of the streams.

This study focused on the assessment of physicochemical properties using standard analytical methods to evaluate the environmental impact of quarrying on surface water qualities. The study used the World Health Organisation (WHO, 2011) water guideline as a standard to compare with the study dataset and control measures.

The purpose of this study is to improve the mechanical property and processing performance and reduce the cost of the polylacticacid/polybutyleneadipate-co-terephthalate(PLA/PBAT) composites, the calcium carbonate (CaCO₃) and compatibilizer styrene-maleicanhydride copolymer (SMA-2025) were added to the PLA/PBAT system, and the effect of CaCO₃ and SMA-2025 on the morphology, structure, mechanical property, thermal property, thermalstability and shape memory property of the CaCO₃/PLA/PBAT composites were studied and discussed.

The CaCO₃/PLA/PBAT shape memory composites were prepared via melt-blending and hot-pressing methods, and the effect of CaCO₃ and SMA-2025 on the property of the composites was investigated via scanning electron microscope, universal testing instrument, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis and DMA, respectively.

The interface property, mechanical property, thermal stability, shape memory recovery ratios and recovery stresses, and processing performance of the CaCO₃/PLA/PBAT shape memory composites were significantly improved by adding of CaCO₃ and SMA-2025. Moreover, the CaCO₃/PLA/PBAT composites have good blowing film processing performance.

This study will provide a reference for the research, processing and application of the high-performance CaCO₃/PLA/PBAT shape memory composites.

Natural food colors used in food are generally perceived as additives. Therefore, many studies have been conducted to prove the health benefits and risks of using natural food colors, which play an important role in the food industry, and to identify realistic stabilization methods. This paper aims to examine the health effects of natural food colors from a pharmacological approach.

The paper searches for relevant literature using keywords such as “natural food coloring”, “stabilization” and “antioxidant effects”. For the case study area, this paper added “food science and technology” to identify methods for stabilizing natural food coloring. From this review, the authors ultimately selected 79 articles that appeared to meet the research objectives.

When using natural food coloring in food, there are concerns about stabilization. However, with the development of food science and technology, the authors have found that there are multi-layer emulsification methods that can be applied before, during and after food manufacturing, and storage standards are also important. Natural food coloring is playing a diverse role in food science.

Natural food coloring has been reported in various types of literature to have antioxidant, anti-inflammatory and antitumor effects. The most common pigments are carotenoids. Considering the positive effects of natural food coloring on human health, the authors suggest future directions for the development of food science and technology and provide a perspective for changing consumer perceptions.

Additive manufacturing (AM), also known as three-dimensional (3D) printing technology, has been used in the health-care industry for over two decades. It is in high demand in the health-care industry due to its strength to manufacture custom-designed and personalized 3D constructs. Recently, AM technologies are being explored to develop personalized drug delivery systems, such as personalized oral dosages, implants and others due to their potential to design and develop systems with complex geometry and programmed controlled release profile. Furthermore, in 2015, the US Food and Drug Administration approved the first AM medication, Spritam® (Apprecia Pharmaceuticals) which has led to tremendous interest in exploring this technology as a bespoke solution for patient-specific drug delivery systems. The purpose of this study is to provide a comprehensive overview of AM technologies applied to the development of personalized drug delivery systems, including an analysis of the commercial status of AM based drugs and delivery devices.

This review paper provides a detailed understanding of how AM technologies are used to develop personalized drug delivery systems. Different AM technologies and how these technologies can be chosen for a specific drug delivery system are discussed. Different types of materials used to manufacture personalized drug delivery systems are also discussed here. Furthermore, recent preclinical and clinical trials are discussed. The challenges and future perceptions of personalized medicine and the clinical use of these systems are also discussed.

Substantial works are ongoing to develop personalized medicine using AM technologies. Understanding the regulatory requirements is needed to establish this area as a point-of-care solution for patients. Furthermore, scientists, engineers and regulatory agencies need to work closely to successfully translate the research efforts to clinics.

This review paper highlights the recent efforts of AM-based technologies in the field of personalized drug delivery systems with an insight into the possible future direction.

Material extrusion (ME) is a low-cost additive manufacturing (AM) technique that is capable of producing metallic components using desktop 3D printers through a three-step printing, debinding and sintering process to obtain fully dense metallic parts. However, research on ME AM, specifically fused filament fabrication (FFF) of 316L SS, has mainly focused on improving densification and mechanical properties during the post-printing stage; sintering parameters. Therefore, this study aims to investigate the effect of varying processing parameters during the initial printing stage, specifically nozzle temperatures, T_n (190°C–300°C) on the relative density, porosity, microstructures and microhardness of FFF 3D printed 316L SS.

Cube samples (25 x 25 x 25 mm) are printed via a low-cost Artillery Sidewinder X1 3D printer using a 316L SS filament comprising of metal-polymer binder mix by varying nozzle temperatures from 190 to 300°C. All samples are subjected to thermal debinding and sintering processes. The relative density of the sintered parts is determined based on the Archimedes Principle. Microscopy and analytical methods are conducted to evaluate the microstructures and phase compositions. Vickers microhardness (HV) measurements are used to assess the mechanical property. Finally, the correlation between relative density, microstructures and hardness is also reported.

The results from this study suggest a suitable temperature range of 195°C–205°C for the successful printing of 316L SS green parts with high dimensional accuracy. On the other hand, T_n = 200°C yields the highest relative density (97.6%) and highest hardness (292HV) in the sintered part, owing to the lowest porosity content (<3%) and the combination of the finest average grain size (∼47 µm) and the presence of Cr23C6 precipitates. However, increasing T_n = 205°C results in increased porosity percentage and grain coarsening, thereby reducing the HV values. Overall, these outcomes suggest that the microstructures and properties of sintered 316L SS parts fabricated by FFF AM could be significantly influenced even by adjusting the processing parameters during the initial printing stage only.

This paper addresses the gap by investigating the impact of initial FFF 3D printing parameters, particularly nozzle temperature, on the microstructures and physical characteristics of sintered FFF 316L SS parts. This study provides an understanding of the correlation between nozzle temperature and various factors such as dimensional integrity, densification level, microstructure and hardness of the fabricated parts.

The purpose of this study is to investigate the effects of a pigment coating on the mechanical properties of fluting paper.

Two different calcium carbonate pigments were used in the preparation of the coated color, precipitated calcium carbonate (PCC) and ground calcium carbonate (GCC). Fluting paper produced by recycling waste paper was used as base paper. The effects of PCC and GCC pigments on mechanical properties were compared. Ring crush test (RCT), corrugating medium test (CMT), corrugating crush test (CCT), tensile and burst strength tests were applied to the coated papers, and the results were compared to the mechanical properties of base paper.

The tensile and burst indices of the coated papers were found to be higher than base papers about 13.9% and 6.05%, respectively. While the coating process positively affected the RCT and CCT values, it did not show a significant impact on the CMT values. GCC, one of the pigments used in coating colors, had a more effective effect on the mechanical properties of fluting papers compared to PCC.

These results suggest that coating of fluting papers has a positive effect on mechanical properties and the use of GCC as a pigment is more effective than PCC.

This study aims to prepare activated carbon (AC) and activated biochar (BC) from sugarcane bagasse (SCB) can be used as carbon black (CB) replacement for styrene butadiene rubber (SBR) composites cured by electron beam (EB) radiation.

This study is carried out to investigate the effect of partial replacement of CB (as traditional filler) by AC or BC prepared from low-cost agricultural wastes (SCB) to improve the properties of SBR rubber cured by EB radiation (doses from 25 to 150 kGy).

The results indicated that the addition of AC or BC leads to improve the physical and mechanical properties of SBR with increasing irradiation dose [especially at concentration of 10 parts per hundred part of rubber (phr) from BC]. Also in this study, this paper examines how exposure of SBR rubber composites to ultraviolet (UV) radiation changes the mechanical properties for these composites, to do that, the specimens were examined before and after they were exposed to UV radiation for 300 h. The results showed that, the irradiated SBR composites, UV exposure, exhibit better retention in mechanical properties as compared with unirradiated ones, and the samples loaded with CB hybrid with ACs had an increased value of tensile strength (TS) retention as compared with blank sample.

The importance of this study is that, the production of AC from SCB offers a huge opportunity to overcome the problem of the disposal of SCB.