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The objective of the research is to evaluate the carbon footprint of the green asparagus (Asparagus officinalis L.) supply chain, encompassing the agricultural production to the packaging stage in Italy, as it is the sixth largest producer and the second largest in Europe. It provides an assessment in the province of Foggia and highlights the global perspective of the carbon footprint application in agro-food systems.

The carbon footprint (ISO 14067:2018) considers 1 t of packaged fresh asparagus as a functional unit in the agricultural production and packaging stage and is based on primary data collected in one of the leading companies of asparagus production in the province of Foggia, which markets about 0.21 kt of asparagus per year produced in about 31 ha. Data were integrated with face-to-face in-depth interviews and pre-filled checklists.

Findings show that the carbon footprint of 1 t of packaged fresh asparagus is equivalent to 335.31 kgCO2eq, of which 61% in the agricultural stage and 39% in the packaging one. The majority of the emissions are associated with the fertigation and the diesel consumption for the transportation of workers. Farmers should adopt green electricity so as to reduce the emissions associated with the electric pump for the extraction of water from artesian wells. Moreover, it would be desirable to replace mineral urea phosphate with organic fertilizers.

To the best of the authors’ knowledge, scholars have not yet investigated the environmental impacts of the green asparagus supply chain, even if it represents one of the most cultivated vegetables worldwide, with a global production that amounts to 8.5 Mt per year.

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.

This study aims to investigate the factors influencing the citrus trade in Indonesia, the effects of tariff and non-tariff policies on the industry and the welfare of producers and consumers.

The research used annual series data from 1991 to 2021 and employed inferential, simulation, and descriptive analyses. The two-stage least squares (2SLS) of 19 simultaneous equations were used to estimate parameters.

The results indicate that free trade policies and restrictions have influenced the citrus industry, leading to a reduction in Indonesian citrus imports, and increased consumer and producer prices. However, eliminating import tariff policies on citrus from China and import restrictions increased producer surplus while decreasing consumer surplus, government revenue, and total welfare. Therefore, trade policies should be combined with non-trade policies such as citrus region development policies and advancing cultivation technology.

This study provides empirical evidence for the Indonesian government to formulate effective citrus trade and development policies. It emphasizes the importance of carefully considering the impact of trade policy on the citrus industry and the need to implement non-trade policies such as citrus zone development policies and advancing cultivation technology to benefit both producers and consumers.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-02-2023-0148

The purpose of this study is to improve the mechanical properties, thermal insulation properties and flame retardant properties of polyethylene terephthalate (PET), the organic montmorillonite (OMMT)/SiO₂ aerogel/PET composites and fibers were prepared, and the effects of the OMMT/SiO₂ aerogel on the structure, thermal conductivity and flame retardance of the OMMT/SiO₂ aerogel/PET composites and their fibers were systematically investigated.

The OMMT/SiO₂ aerogel/PET composites and fibers were prepared by in-situ polymerization and melt spinning using SiO₂ aerogel as thermal insulation filler and OMMT (DK2) as comodified filler.

The experimental results showed that OMMT improved the crystallization properties of PET. Compared with the crystallinity of SiO₂ aerogel/PET composites (34.8%), SiO₂ aerogel/PET composites and their fibers reached 45.1% and 49.2%, respectively. The breaking strength of the OMMT/SiO₂ aerogel/PET composite fibers were gradually increased with the OMMT content. When the content of OMMT was 0.8 wt.%, the fracture strength of the composite fibers reached 4.40 cN/dtex, which was 54% higher than that of the SiO₂ aerogel/PET fiber. In addition, the thermal insulation properties of the composites and their fibers were improved by addition of fillers, and at the same time reached the flame retardant level. The thermal conductivity of the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites was 101.78 mW/(m·K), which was 49.3% and 58.8% lower than that of the SiO₂ aerogel/PET composites and the pure PET, respectively. The thermal conductivity of the fiber fabrics woven from the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites was 28.18 mW/(m·K), which was 29.0% and 44.6% lower than that of the SiO₂ aerogel/PET composite fiber fabrics and PET fiber fabrics. The flame retardancy of the composites was improved, with an limiting oxygen index value of 29.2% for the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites, which was 4.1% higher compared to the SiO₂ aerogel/PET composites, and achieved the flame retardant level.

The SiO₂ aerogel/PET composites and their fibers have good mechanical properties, flame retardant properties and thermal insulation properties, exhibited good potential for application in the field of thermal insulation, such as warm clothing. Nowadays, as the energy crisis is becoming more and more serious, it is very important to improve the thermal insulation properties of PET to reduce energy losses and mitigate the energy crisis.

In this study, PET based composites and their fibers with excellent mechanical properties, thermal insulation properties and flame retardant property were obtained by using three-dimensional network porous silica aerogel with low density and low thermal conductivity as the thermal insulation functional filler and two-dimensional layered OMMT as the synergetic modified filler.

To improve the corrosion resistance of magnesium alloys, the construction of protective coatings is necessary to extend the service life of Mg-based materials.

SiO₂ nanoparticles modified by dodecyltrimethoxysilane (DTMS) were added to the PP and a superhydrophobic Mg(OH)₂/PP-60mSiO₂ composite coating was fabricated on the surface of AZ31 magnesium alloy via the hydrothermal method and subsequently the immersion treatment.

Hydrophilic SiO₂ nanoparticles become hydrophobic after modified by DTMS, showing a higher dispersibility in xylene. By incorporating modified SiO₂ nanoparticles into the composite PP coating, the hydrophobicity of the layer was enhanced, resulting in a contact angle of 166.3° and a sliding angle of 3.4°. It also improved the water repellency and durability of the coating. Furthermore, the intermediate layer of Mg(OH)₂ significantly strengthened the bond between the PP layer and the substrate. The Mg(OH)₂/PP-60mSiO₂ composite coating significantly enhances the corrosion resistance of the magnesium alloy by effectively blocking the infiltration of the corrosion anions during corrosion. The corrosion current density of the Mg(OH)₂/PP-60mSiO₂ composite coating is approximately 8.23 × 10^–9 A·cm^-2, which can achieve a magnitude three times lower than its substrate, making it a promising surface modification for the Mg alloy.

The composite coating effectively and durably enhances the corrosion resistance of magnesium alloys.