Search Results (49)

Due to the absence of engine noise in new energy vehicles, road noise and wind noise become particularly noticeable. Therefore, studying the noise transmission through car doors is essential to effectively reduce the impact of these noises on the passenger compartment. To address the optimization of the sound absorption performance of single-layer porous plates combined with lightweight glass wool used in the doors of electric vehicles, this study established a microscopic acoustic performance analysis model based on the transfer matrix method and sound transmission loss theory. The effects of medium type, perforation rate, perforation radius, material thickness, and porosity on the sound absorption coefficient, impedance characteristics, and reflection coefficient were systematically investigated. Results indicate that in the high-frequency range (above 1200 Hz), the sound absorption coefficients of both rigid and flexible media can reach up to 0.9. When the perforation rate increases from 0.01 to 0.2, the peak sound absorption coefficient in the high-frequency band (1400–2000 Hz) rises from 0.45 to 0.85. Increasing the perforation radius to 0.03 m improves acoustic impedance matching. This research provides theoretical support and a parameter optimization basis for the design of acoustic packaging materials for electric vehicles, contributing significantly to enhancing the interior acoustic environment. Full article

Plums are one of the most important stone fruits worldwide. Surprisingly, the effect of UV-C light on improving their bioactive compounds and its effect during storage has not been explored. This research aimed to assess the effect of UV-C light on the bioactive compounds and antioxidant capacity of plums, as well as to evaluate the storage conditions on the quality attributes of these fruits. Plums were UV-C light-irradiated (0, 0.175, and 0.356 kJ/m²) to analyze their effect on phenolic compounds, total anthocyanins, and antioxidant capacity. A selected dose of UV-C light treatment was applied to plums as a pretreatment to assess the effect of packaging (non-packed, packed in closed polyethylene boxes, and packed in closed polyethylene boxes with perforations) and temperature (5, 15, and 20 °C) on the quality characteristics of plums using a 3² experimental design. The results showed that phenolic compounds (3–10%), total anthocyanins (22–39%), and antioxidant capacity (8–15%) increased with the UV-C light treatment (0.356 kJ/m²). In storage, firmness remained constant, and color parameters (a* and b*) were reduced in all conditions, whereas weight loss was lower in plums stored in closed packages. Moreover, total anthocyanins and antioxidant capacity were enhanced under all storage conditions. The microbial load decreased due to the UV-C light treatment and remained constant during storage time (<100 CFU/g). Storing the plums at a low temperature in a closed package effectively preserved the quality attributes of plums for 40 days without affecting the sensory acceptance. Full article

Background: Chronic otitis media (COM) with tympanic perforation sometimes requires tympanoplasty. Many factors can interfere with surgical success; however, the histological status of the remaining epithelium of the perforation has not been studied as a risk factor for surgical failure. Methods: This was an observational, longitudinal, and analytical study in patients with COM, candidates for tympanoplasty who met the inclusion criteria, between August and December 2024. Tympanoplasty was performed, and the tympanic ring epithelium was sent for histological analysis. After 30 days, closure or non-closure of the perforation was determined, and the results were collected. Descriptive and analytical statistics were performed according to data distribution using the SPSS 26.0 statistical package. Results: Twenty subjects were included, 80% with tubal dysfunction, 60% with central perforation, and 65% with medium-sized. In total, 13 were successful, and 7 failed. Histopathological analysis revealed dystrophic calcification, chronic lymphocytic infiltrate, histiocytic infiltrate, fibrosis, loose keratin sheets, metaplasia, and spongiosis. The logistic regression model showed an OR of 7.3 for marginal perforation and 3.4 for the OPSS score. Of the patients with surgical failure, 57.4% had epithelial inflammation. Conclusions: epithelial inflammation affected surgical success in more than 50%. Full article

This study aimed to develop an active biodegradable bio-based (polylactic acid/PLA) equilibrium modified atmosphere packaging (EMAP) containing a carvacrol-emitting sachet (created by poly-hydroxybutyrate) (PLA-PHB-CARV) to extend the shelf-life of cherry tomatoes at 15 °C and 25 °C. Cherry tomatoes in macro-perforated polypropylene (PP) films (mimicking the commercial packaging) or in PLA-based micro-perforated film without the carvacrol sachet (PLA) were also tested. Weight loss, decay, headspace gases, pH, titratable acidity (TA), total suspended solids (TSS), ripening index, color, texture, total viable counts (TVC), and sensory analysis were performed. Decay was 40% in PLA-PHB-CARV, and 97% in PP after 20 days at 25 °C. PLA-PHB-CARV showed lower weight loss (p < 0.05) and stable firmness compared to PP and PLA at both temperatures. TSS and TA were not affected by the packaging at 15 °C, while at 25 °C, the TSS accumulation was inhibited in PLA-PHB-CARV compared to in PLA and PP (p < 0.05), indicating a notable delay in the ripening process. PLA-PHB-CARV retained their red color during storage compared to PP and PLA. Carvacrol addition inhibited TVC compared to PP and PLA by ca. 2.0 log CFU/g during storage at 25 °C, while at 15 °C, the packaging did not reveal a significant effect. Overall, the results indicated that the developed active EMAP may be adequately used as an advanced and alternative packaging for tomatoes or potentially other fruits with a similar respiration rate versus their conventional packaging, showing several advantages, e.g., a reduction in petrochemical-based plastics use, shelf-life extension of the packaged food, and consequently, the perspective of limiting food waste during distribution and retail or domestic storage. Full article

Very large quantities of stone waste sludge are disposed in exhausted quarries and have a very low reuse rate to date. The paper considers the possibility of using these types of industrial waste in partial substitution of natural aggregates for the production of lime-based plasters. Traditional materials based on lime, the only material with a carbon neutrality life cycle, have considerable potential for use as components of green materials for plastering and finishing building surfaces in both new construction and historic heritage conservation. The paper presents the preliminary results of a research activity aimed at developing pre-packaged products based on Traditional Lime Putty (TLP) by partially replacing natural aggregates with Stone Waste Sludge (SWS), with a low rate of recovery from the Apricena limestone production district in Apulia. The mineralogical and chemical analysis carried out using XRD (X-Ray Diffraction), TG-DTA (Thermo Gravimetry-Differential Thermal Analysis), and hydrochloric acid attack test showed that the SWS consisted of 98.4 % CaCO₃ by mass. The particle sizes measured by laser diffraction technique are below 22.5 μm for the 92% mass of the sample. The high fineness of the stone waste was confirmed by the Blaine-specific surface method, which equals to 9273.79 cm²/gr. The behavior of three fresh mixtures for prepacked coarse plaster, fine plaster, and finishing plaster with 12.90%, 17.94%, and 18.90 by mass of SWS, respectively, was evaluated by spreading test and applicability tests on a perforated ceramic slab. The finishing plaster has the highest consistency value of 235 mm, while the fine plaster and the coarse plaster have values of 205 mm and 155 mm, respectively. The coarse plaster is suitable for use as base plaster (arriccio) or second layer rendering (tonachino) up to a thickness of approximately 1 cm. Both the fine plaster and finishing plasters can be used for the surfaces finishing with the application of layers of a few millimeters thick. Full article

This research concerns the development and implementation of ground-breaking strategies for improving the sorting, separation, and recycling of common flexible laminate packaging materials. Such packaging laminates incorporate different functional materials in order to achieve the desired mechanical performance and barrier properties. Common components include poly(ethylene) (PE), poly(propylene) (PP), and poly(ethylene terephthalate) (PET), as well as valuable barrier materials such as poly(vinyl alcohol) (PVOH) and aluminium (Al) foils. Although widely used for the protection and preservation of food produce, such packaging materials present significant challenges for established recycling infrastructure and, therefore, to our future ambitions for a circular economy. Experience from the field of ionic liquids (ILs) and deep eutectic solvents (DESs) has been leveraged to develop novel green solvent systems that delaminate multilayer packaging materials to facilitate the separation and recovery of high-purity commodity plastics and aluminium. This research focuses on the development of a hydrophobic DES and the application of a Design of Experiments (DoE) methodology to investigate the effects of process parameters on the delamination of PE/Al/PET laminate packaging films. Key variables including temperature, time, loading, flake size, and perforations were assessed at laboratory scale using a 1 L filter reactor vessel. The results demonstrate that efficient separation of PE, Al, and PET can be achieved with high yields for material and solvent recovery. Recovered plastic films were subsequently characterised via Fourier-transform infra-red (FTIR) spectroscopy, Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) to qualify the quality of plastics for reuse. Full article

This study aimed to assess the cold storage preservation of ‘BRS Vitoria’ seedless grape by combining SO₂-generating pads. ‘BRS Vitoria’ grapes were freshly harvested from a commercial vineyard in Marialva, PR, Brazil. The trial was carried out in a completely randomized design with four treatments and five replications, and each plot consisted of five bunches individually packaged in clamshells. Treatments included (a) control (without SO₂ pads), (b) field ultrafast SO₂-generating pad before packaging (FieldSO₂), (c) dual-release SO₂-generating pad during cold storage (DualSO₂), and (d) FieldSO₂ + DualSO₂. After being harvested, bunches subjected to FieldSO₂ treatments were placed in a 20 kg harvest box with perforated liners. Subsequently, the FieldSO₂ was placed on top of the grapes, and the liner was sealed for 4 h. Afterwards, bunches were packaged according to the treatments, and the boxes were kept in cold storage (1 °C ± 1 °C) for 60 days and at room temperature for 3 days. After 60 days of cold storage, by using a combination of FieldSO₂ and DualSO₂ pads, the cold preservation of ‘BRS Vitoria’ grape bunches can be extended up to 60 days with total absence of gray mold with fresh stems, with no negative impact on weight loss, shattered berries or even bleaching. This treatment can be used to optimize the cold storage period of ‘BRS Vitoria’, especially for export markets, where long periods of cold preservation are required. Full article

The impact of perforation patterns on the compressive strength of cardboard packaging is a critical concern in the packaging industry, where optimizing material usage without compromising structural integrity is essential. This study aims to investigate how different perforation designs affect the load-bearing capacity of cardboard boxes. Utilizing finite element method (FEM) simulations, we assessed the compressive strength of packaging made of various types of corrugated cardboards, including E, B, C, EB, and BC flutes with different heights. Mechanical testing was conducted to obtain accurate material properties for the simulations. Packaging dimensions were varied to generalize the findings across different sizes. Results showed that perforation patterns significantly influenced the compressive strength, with reductions ranging from 14% to 43%, compared to non-perforated packaging. Notably, perforations on multiple walls resulted in the highest strength reductions. The study concludes that while perforations are necessary for functionality and aesthetics, their design must be carefully considered to minimize negative impacts on structural integrity. These findings provide valuable insights for designing more efficient and sustainable packaging solutions in the industry. Full article

A crop pretreatment with silicon was combined with passive modified atmosphere packaging (PMAP) in a thermoformed recycled PET packaging format as a novel approach to minimize the quality degradation in mushrooms. This study was aimed to evaluate the effects of (a) two preharvest treatments, namely preharvest control (PHTC) and preharvest silicon treatment (PHTS) and (b) four packaging lid formats, namely PMAP1: a single hole of 1.1 mm size, PMAP2: two holes of 0.53 mm size, PMAP3: three holes of 0.53 mm size, and PMAPC: OMNI-PW micro perforated cling film as a control on the quality and shelf life of mushrooms during five days of storage at 4 °C and 99.9% RH. The results of the analysis of variance showed that packaging type, storage days, and the double interaction effects of storage days × packaging type had significant effects (p < 0.0001) on the changes in O₂, CO₂, colour L* and a* values, ΔE, total soluble solids (TSS), and the density of mushrooms. Density, electrolyte leakage (EL), and TSS were significantly affected by the double interaction effects of preharvest treatment × packaging type. Overall, PMAP1, PMAP2, and PMAP3 resulted in lower O₂ + higher CO₂ within packages compared with the conventional control. A preharvest silicon treatment had little overall effect. PMAP 1, 2 and 3 had a significantly lower ΔE (=better quality) after 5 days storage compared to PMAPC which had the highest ΔE (lowest quality) overall. PMAP1 and PMAP2 had the lowest EL values compared to PMAP3 and PMAPC. PMAP1, PMAP2, and PMAP3 all gave better TSS levels and density compared to PMAPC. Notably, this study proved that a perforation-mediated MAP design for mushrooms packaged in a thermoformed recycled PET packaging format maintained improved CO₂, lowered O₂, and reduced EL while maintaining TSS and the density of the mushrooms during the storage period. Full article

Poly-(Lactic Acid) (PLA) is regarded as one of the most promising bio-based polymers due to its biocompatibility, biodegradability, non-toxicity, and processability. The investigation of the potential of PLA films in preserving the quality of strawberries is fully in line with the current directives on the sustainability of food packaging. The study aims to investigate the effects of PLA films on strawberries’ physical and chemical properties, thereby determining whether they can be used as a post-harvest solution to control antioxidant loss, reduce mold growth, and extend the shelf-life of strawberries. Well-designed PLA films with different-sized holes obtained by laser perforation (PLA₀, PLA₁₆ and PLA₂₃) were tested against a conventional packaging polypropylene (PP) tray for up to 20 days of storage. Weight loss and mold growth were significantly slower in strawberries packed in PLA films. At the same time, PLA-based films effectively preserved the deterioration of vitamin C content, polyphenols and antioxidant activity compared to the control. Furthermore, among all, the micro-perforated PLA film (PLA₂₃) showed better preservation in the different parameters evaluated. These results could effectively inhibit the deterioration of fruit quality, showing promising expectations as an effective strategy to extend the shelf-life of strawberries. Full article

Polymers generally form incompatible mixtures that make the process of recycling difficult, especially the mechanical recycling of mixed plastic waste. One of the most commonly used films in the packaging industry is multilayer films, mainly composed of polyethylene (PE) and polyamide (PA). Recycling these materials with such different molecular structures requires the use of compatibilizers to minimize phase separation and obtain more useful recycled materials. In this work, commercial polyisoprene–graft–maleic anhydride (PI-g-MA) was tested as a compatibilizer for a blend of PE and PA derived from the mechanical recycling of PE/PA multilayer films. Different amounts of PI-g-MA were tested, and the films made with 1.5% PI-g-MA showed the best results in terms of mechanical properties and dart impact. The films were also characterized thermally via thermogravimetric analysis (TG) and differential scanning calorimetry (DSC), using Fourier-transform infrared spectroscopy (FTIR), and morphologically using a scanning electron microscope (SEM). Other parameters, such as tearing and perforation, were analyzed. Full article

Prickly pears (Opuntia ficus-indica), which are well known for their beneficial properties for human health, are the subject of many studies due to their high content of bioactive compounds. However, the presence of spines on the fruit’s surface is a factor that limits consumption. Therefore, the viability and nutritional quality of peeled and packaged white, orange, and pink prickly pears were studied during storage. Refrigerated whole fruits stored at 8 °C and 85% RH for 0, 1, 2, 3, or 4 weeks were electrically peeled and packaged with micro-perforated film. At each time point, their microbial quality; physical parameters, such as hardness, texture, and color; and chemical parameters, including pH, titratable acidity, total soluble solids content, sugar content, ascorbic acid content, antioxidant capacity, and total phenol content, were analyzed. The mesophilic aerobic counts were lower than the values established by Spanish legislation (7 log (CFU/g f.w.)) until day 8 after packaging (or until day 6 after 4 weeks of storage). The hardness, texture, pH, sugar content, ascorbic acid content, and antioxidant capacity decreased significantly between day 0 and day 8 after packaging, independently of the number of weeks for which the whole fruits had been refrigerated previously. Furthermore, the changes in the parameters analyzed for whole fruits during storage were less remarkable. The evaluation of the sensory features was positive throughout the preserved period. The minimally processed prickly pears retained suitable microbial, nutritional, and sensory qualities when the whole fruits had been refrigerated for 1, 2, 3, or 4 weeks, facilitating their management in small processing companies. Full article

One of the main trends in the development of the modern electronics industry is the miniaturization of electronic devices and components. Miniature electronic devices require compact cooling systems that can dissipate large amounts of heat in a small space. Researchers are exploring ways to improve the design of the heat sink of the cooling system in such a way that it increases the heat flow while at the same time reducing the size of the heat sink. Researchers have previously proposed different designs for heat sinks with altered fin shapes, perforations, and configurations. However, this approach to optimizing the design of the heat sink results in an increase in the labor intensity of its production. Our goal is to optimize the heat sink design to reduce its size, reduce metal consumption, and increase heat flow. This goal is achieved by changing the number of fins and the distance between them. In this case, there is no significant difference in the geometry of a conventional plate-fin heat sink, and a low labor intensity of production is ensured. A numerical investigation of heat flow and pressure drop in models of plate-fin heat sinks of various sizes and metal volumes was conducted using the ANSYS Fluent software package (v. 19.2) and computational fluid dynamics employing the control volume method. We used the SST k-ω turbulence model for the calculations. The research results showed that by changing the number of fins and the distance between them, it is possible to increase the heat flow from the heat sink to 24.44%, reduce its metal consumption to 6.95%, and reduce its size to 30%. The results of this study may be useful to manufacturers of cooling systems who seek to achieve a balance between the compactness of the heat sink and its ability to remove large amounts of heat. Full article

Sulfur dioxide (SO₂)-generating pads associated with perforated plastic liners are often used to control gray mold in table grapes during cold storage; however, SO₂ may cause bleaching, shattered berries, and an unwanted taste. To overcome this difficulty, a field ultrafast SO₂-generating pad was designed to be used for a few hours before packaging grape bunches as an alternative for eradicating spores of fungi from berry skin. This study aimed to assess the postharvest conservation and shelf life of ‘Italia’ table grapes packaged in plastic clamshells and perforated plastic liners using the field ultra-fast SO₂-generating pads before packaging, associated with or without slow- or dual-phase SO₂-generating pads during cold storage. The packaged grapes were cold stored (1.0 ± 1.0 °C; 95% relative humidity), and after 45 d, grapes were placed at room temperature (22.0 ± 1.0 °C) without plastic liners and SO₂-generating pads for 3 d. Before and after the grapes had been subjected to the field ultra-fast SO₂-generating pads, the quantification of filamentous fungi on the surface of the berries was assessed. The use of field ultra-fast SO₂-generating pads before packaging, associated with slow- or dual-phase SO₂-generating pads during cold storage, resulted in a lower incidence of gray mold after 45 d of storage, with low weight loss and shattered berries, good preservation of stem freshness, and no impairment in the color and firmness of the berries. Additionally, a significant decrease in disease incidence was observed when using only the dual-phase SO₂-generating pads in cold storage, with good maintenance of bunch quality. Full article

Marketing melons (Cucumis melo) as convenient fresh-cut products is popular nowadays. However, damage inflicted by fresh-cut processing results in fast quality degradation and food safety risks. The life of fresh-cut produce can be extended by a modified atmosphere (MA), either generated in a package by tissue respiration (a passive MA) or injected by gas flushing (an active MA). This work investigated the effect of passive and active MA formed in packages of different perforation levels on the quality of fresh-cut melons of two genetic groups: C. melo var. cantalupensis, characterized by climacteric fruit behavior, and non-climacteric C. melo inodorus. The best product preservation was achieved in passive MA packages: non-perforated for inodorus melons and micro-perforated for cantalupensis ones. The optimal packages allowed for the preservation of both genotypes for 14 days at 6–8 °C. The major factors limiting the shelf life of fresh-cut melons were microbial spoilage, translucency disorder and hypoxic fermentation associated with cantalupensis melons with enhanced ethyl acetate accumulation. Inodorus melons were found to be preferable for fresh-cut processing since they were less prone to fermented off-flavor development. Full article