Polyethylene Films Research Articles

Analysis and Research on Production Effects of Full-Film Double Ridge-Furrow Mulching with Polyethylene Film and Biodegradable Film Based on AquaCrop

Water is an important factor limiting the development of arid rain-fed agriculture. Film mulching is an effective way to ensure yield in arid areas. However, whether biodegradable film can be used instead of polyethylene film for agricultural production in arid areas is a matter of contention. In this study, AquaCrop model simulation and field experiment were used to analyze the production effect of corn whole film double ridge furrow sowing technology covering polyethylene film (PM) and biodegradable film (BM) in Dingxi City from 2016 to 2020. The results showed that the AquaCrop simulation data have a high fitting with the field test data, and the model was suitable for simulating dry farming in Dingxi City. The best sowing time in Dingxi City is to select the average temperature to be stable at about 15 °C (around 15 April to 25 April each year), and the yield is the highest after sowing during this period. Although BM can achieve environmental protection and energy saving, it is weaker than PM in water storage and soil evaporation inhibition in arid areas. The average yield, aboveground biomass, water productivity, and harvest index of PM were 63.95%, 18.57%, 76.35%, and 38.22% higher than those of BM, respectively. In drought years, BM water stress on leaf expansion, induced stomatal closure, and premature senescence were 61%, 17%, and 9.5% higher than PM, respectively, and the stress time was 28.5 d, 5 d, and 26 d, respectively. The maximum canopy coverage and effective root zone water content were 24.5% and 30.49% lower, respectively. In the wet year, water stress under BM only had a certain effect on the leaf expansion of crops but had no effect on the induction of stomatal closure and premature senescence. The maximum canopy coverage and effective root zone water content were 13.56% and 31.35% lower, respectively. The above studies show that BM has a certain ability to store water and preserve moisture, but the parameters of PM are better than BM. Especially in dry years, the crop production efficiency of PM is more significant. It can be seen that in rain-fed agricultural areas with rainfall less than 500 mm, biodegradable film can not replace polyethylene film.

МОДИФИЦИРОВАННЫЕ В ПЛАЗМЕ СКОЛЬЗЯЩЕЙ ДУГИ ГИДРОИЗОЛЯЦИОННЫЕ ПОЛИМЕРНЫЕ ПЛЕНКИ

The article considers the use of polyethylene modified in sliding arc plasma as a waterproofing material. It assesses influence of plasma modification on physical and mechanical properties of polyethylene films by testing for relative elongation and maximum load. The study establishes increase in the size of supramolecular structures in crystalline parts, changing the strength properties of polymer film. It has been experimentally proven that application of 10-second plasma modification by sliding arc using the developed plasma installation results in formation of activated layer on the surface of polyethylene films, which increases the strength characteristics of the material. It has been determined that modifying the polyethylene within 10 seconds increases the strength of the polymer films. Due to increased mechanical strength and changed surface structure, modified polyethylene films are of interest as a base material for creating polymer-roll waterproofing materials.

Effect of duration and infection control barriers of light curing unit on hardness of Bulk Fill composite resin.

This study aimed to investigate the impact of the duration of light curing unit (LCU) usage and the use of infection control barriers on the hardness of Bulk Fill composite resin after curing. The hypotheses were that extended usage of the LCU would not reduces its output power and resin hardness, and that the presence of polyethylene film barriers exacerbates the reduction in resin hardness. Based on the absence or presence of polyethylene film (PE) and the number of layers used, a 3M LED curing light (EliparTM DeepCure-S; 3M ESPE, St Paul, MN, USA) was divided into three groups: PE0, PE1, and PE3. The curing light was used 30 times daily for 20 s per exposure, at frequencies of 0, 6, and 12 months. Maximum output power tests were conducted for each group of curing lights. Custom-made plastic modules were used to stack Bulk Fill composite resin (Filtek Bulk Fill Posterior Restorative; 3M ESPE) to a thickness of 4 mm. Each group of curing lights was used to cure the modules in a direct contact manner for 20 s. Vickers hardness measurements were taken at the top and bottom surfaces of the resin specimens using a digital microhardness tester. A one-way or two-way ANOVA analyzed the power of LCUs, Vickers hardness of Bulk Fill composite resin, and hardness decrease percentage across groups. Pairwise comparisons used the Tukey test (α = 0.05). As the duration of usage increased, both the power of the curing light and the hardness of the resin significantly decreased. Significant differences were observed in power and resin hardness among the PE0, PE1, and PE3 groups. When the duration of usage was 6 months or less, only multi-layered PE films led to a significant increase in the percentage decrease of hardness of cured resin from top to bottom. However, at 12 months, both single-layer and multi-layered PE films resulted in a significant increase in the percentage decrease of hardness of cured resin from top to bottom. The output power of the light curing unit decreases with prolonged usage, thereby failing to meet the curing requirements of Bulk Fill composite resin. The use of single-layer PE as an infection control barrier is recommended.

Watermelon yield in both mulched and unmulched fields: The impact of drip irrigation on watermelon production

Four irrigation regimes were established, varying the amount of irrigation water applied: 60%, 65%, 70%, and 75% of the soil moisture. The fields were left without mulch or covered with white and black polyethylene films. Prior to irrigation, the soil moisture in this case ranged from 60% to 75% in the 0-20 cm soil layer during the “sowing -shatrik” phase and in the 0-40 cm soil layer during the “shatrik -bloom” period, according to the experimental alternatives. During the time of “bloom fruit formation,” the soil layer from 0 to 50 cm was maintained at levels of 70%, 75%, 80%, and 85%. Similarly, during the “fruit formation ripening” period, the soil layer from 0 to 50 cm was maintained at levels of 60%, 65%, 70%, and 75%. One of the study options was the use of drip irrigation, which maintained soil moisture levels at 70%, 80%, or 70% depending on the phenophases of the watermelon plant. This approach led to a significant increase in both the production and quality of the watermelon crop.

Bio-high density polyethylene films embedded with organoclay and zinc pyrithione

Bio-high density polyethylene films embedded with organoclay and zinc pyrithione

Linear dichroism and linearly polarised luminescence spectra of oriented samples collected on a new integrated instrument.

Linearly polarised luminescence (LPL) has a wide range of potential applications giving optical and geometric parameters for oriented lumiphores. In this work we present the first wavelength scanned LPL spectra. Analytes are either oriented on stretched polyethylene films or in flow. Applications of the wavelength-dependence of g-factors are illustrated.

Weathering of agricultural polyethylene films in cold climate regions: which parameters influence fragmentation?

A combination of parameters is involved during the natural weathering of plastic much films, which could lead to the acceleration of their fragmentation into microplastics or the leaching of additives.

A porous micro/nano-structured polyethylene film prepared using a picosecond laser for agricultural passive cooling.

Passive cooling materials, as a promising choice for mitigating the global energy crisis, have limited use as their cooling effects are usually weakened or lost by dust contamination. In this study, a passive cooling polyethylene (PE) film with self-cleaning properties is prepared by picosecond laser ablation. Numerous root-like hierarchical porous micro/nano-structures were obtained on the double side of the PE film. The outside (toward air) shows excellent self-cleaning, corrosion resistance, and anti-friction properties. The inside (towards crops) further reduced the transmittance and water vapor evaporation (keeping the soil moist). Compared with the pristine PE film, the transmittance of the as-prepared double-sided micro/nano-structured PE film decreased by about 40%. In addition, during the crop cultivation experiment, the temperature of the crop leaves was reduced by 2.7-7 °C and showed a higher plant height and greater leaf width under the cover of the laser-treated film. This demonstrates that the passive cooling PE film has an excellent temperature regulation ability and good practical application effects. This study proposes a simple strategy based on a picosecond laser for the preparation of passive cooling materials, which are beneficial for alleviating energy crises and promoting sustainable development.

The Influence of Scanning Speed on the Removal of Polyethylene Films with Different Colors by 1 μm Continuous Laser was Studied

The Influence of Scanning Speed on the Removal of Polyethylene Films with Different Colors by 1 μm Continuous Laser was Studied

Determination of the ability of a solar dryer based on a polyethylene ceramic composite to dry vegetables of various thicknesses

This article compares the results of drying red and green bell peppers in solar dryers based on polyethylene ceramic composite and traditional solar dryers made of polyethylene film. In particular, samples with a height of 5 mm and 10 mm were analyzed. As a result, the influence of the ability of pulsed energy of the infrared spectrum generated by the composite to penetrate into the product on efficiency was determined. It has been established that red bell peppers are effective up to 3% and green bell peppers up to 10%.

IMPROVED LEVEL OF TECHNOGENIC SAFETY IN PLANTS INTENDED MUNICIPAL SOLID WASTE INCINERATION

Solid municipal waste can be an alternative and renewable type of fuel. Waste incineration provides effective disposal, significant volume reduction and utilization of the energy potential of the carbon waste part. In order to protect the components of the biosphere and service personnel from harmful substances that are formed in the furnace space, it is first necessary to assess the chemical composition and volume of emissions. The purpose of the work is to study the process of burning municipal waste, determine the heat energy obtained, determine the amount of air required for the complete combustion reaction, and determine the volume of flue gases produced as a result of combustion. To achieve the goal of the research, a complex of methods of system analysis and the method of data analysis was applied. An analysis of modern international literary sources, an analysis of the morphological composition of the combustible part of solid household waste, and an analysis of the interaction of chemical substances was carried out. For the research, several components of waste were collected, which were conditionally divided into two main groups - paper and plastic. The first group includes waste, which includes wood, cardboard, and paper. The second group (plastic) includes waste, which includes plastic in the form of scraps of polyethylene film, disposable dishes. As a result of the research, a theoretical volume of combustion products was obtained for the further design of the system of protection of the environment and service personnel from emissions of thermal disposal of solid household waste. Research results can be used in the design of municipal waste incineration equipment. The system of using the heat of flue gases generated after burning waste to dry the waste before feeding it to the furnace is of great importance for saving additional fuel.

EVALUATION OF SOME CUCUMBER HYBRIDS (CUCUMIS SATIVUS L.) FOR QUALITY TRAITS

Cucumber (Cucumis sativus L.) is a species of the Cucurbitaceae family cultivated mainly in protected areas in Romania. Cucumber fruits are sources of nutrients necessary for human health, and awarness of quality attributes can satisfy the demands of consumers who are becoming more informed lately. The aim of the study was to analyze of some quality indices in two hybrids of cucumbers, Amour F1 and Capricorn F1 grown in solar, on a soil mulched with black polyethylene film. The quality analyzes were performed immediately after harvesting, at technological maturity and were focused on: ph, titratable acidity, SSC, reducing sugars, glucose, fructose, ascorbic acid, total phenolics and flavonoids content. The results showed that the hybrid Amour F1 recorded higher values in terms of content in SSC, ascorbic acid and total phenolics and in mulched variants compared to the variantes without mulching.

RESEARCH ON THE INFLUENCE OF SOME TECHNOLOGICAL FACTORS ON PRODUCTION IN PLASTIC TUNNEL TOMATO CULTIVATION

Tomatoes (Lycopersicon esculentum Mill.) are native to Central and South America. The comparative experiments with the two tomato varieties took place in the period 2022-2023 and were organized in a 160 m2 plastic tunnel from the Lovrin Research and Development Station, Timiș County, Romania. The experimental variants were placed according to the model of bifactorial experiments with subdivided plots, in 3 repetitions, namely: factor A (genetic factor – variety) with two gradations: a1 – 'Elisabeta' and a2 – 'Ruxandra', respectively factor B (technological factor) with two gradations: b1 – unmulched and b2 – mulched. To evaluate the production capacity, observations were made at the time of harvesting in terms of the number of fruits in each inflorescence and fruit weight, using current work techniques and precision equipment. The combined influence of genetic and technological factors highlights a distinctly significant difference in the average production per plant in the case of the tomato variety 'Ruxandra' grown on soil mulched with polyethylene film in the plastic tunnel. Soil mulching, as an experimental technological factor, causes a 20-25% increase in production, compared to the control variant.

Computational fluid dynamics and artificial neural networks for modelling lined irrigation canals with low‐density polyethylene and cement concrete liners

AbstractThis study numerically investigated the lining effect on the discharges and seepage losses of five reaches which belong to the El‐Sont Canal, Asyut, Egypt, using FLOW‐3D and Slide2 models, respectively. Two lining materials were considered, cement concrete (CC) and CC with low‐density polyethylene (LDPE) film. A cost analysis was performed to explore the feasibility of the proposed lining materials. Moreover, a parametric study was conducted by the Slide2 model to investigate the effect of canal geometry and liner properties on seepage losses. An artificial neural network (ANN) model was developed based on the Slide2 model scenarios to estimate the seepage losses from lined irrigation canals. The results showed that reach the discharge calculated from the FLOW‐3D model increased by 92%–97% and 149%–156%, while the calculated seepage losses from the Slide2 model decreased by 81%–87% and approximately 97% under CC and CC with LDPE film liners, respectively. Cost analysis revealed that the overall cost of CC with LDPE film was higher by 14% than CC. Relying on the importance of saving irrigation water and conveying water to the last reaches, CC with LDPE film is recommended for lining irrigation canals. A parametric study showed that the seepage losses were reduced by more than 96% when the ratio between liner and soil hydraulic conductivities was less than 0.01. A thick liner could maximally decrease the seepage losses by 68%, regardless of the canal geometry. As the developed ANN model showed a close agreement with the Slide2 results with coefficient of determination (R2) and mean squared error values of 0.99 and 0.05, respectively, the ANN model is recommended as a robust and rapid tool for estimating seepage losses from lined irrigation canals.

Superabsorbent whey protein isolates/chitosan-based antibacterial aerogels: Preparation, characterization and application in chicken meat preservation

Traditional absorbent pads are composed of hard-to-degrade polyethylene film and non-woven bottom layer, which have the characteristic of low absorption rate, without antibacterial effect. The objective of this study is to fabricate a novel superabsorbent and antibacterial aerogel, which consists of whey protein isolate (WPI) and chitosan (CS). The citric acid (CA) and ε-polylysine hydrochloride (ε-PLH) are incorporated into WPI/CS-based aerogel as cross-linking and antibacterial agent, respectively. The application in meat preservation as an absorbent pad is investigated. Results of water absorption, water vapor absorption and stress-strain show that aerogel comprised of 6 % WPI, 1.2 % CS, 2.0 % CA, and 2.0 % ε-PLH have the best water absorption capacity and stress. The density of WPI/CS/CA/ε-PLH aerogel is 82.7 ± 6.4 mg/cm3, and has a uniform and polyporous microstructure, resulting in superabsorbent capacity. Antibacterial rate of WPI/CS/CA/ε-PLH aerogel against Staphylococcus aureus, Escherichia coli, Salmonella and Listeria monocytogenes reach around 80 %. The WPI/CS/CA/ε-PLH aerogel significantly reduces increased velocity of b⁎, pH, total volatile base nitrogen, and total viable counts and decreased velocity of L⁎ and b⁎ of chicken meat (P < 0.05). Results indicate WPI/CS/CA/ε-PLH aerogel effectively extends shelf-life of chicken meat to 7 days, and could be used as an absorbent pad in meat preservation.

Green synthesis of carbon nanoparticle-reinforced nanocomposites with gallic acid as a crosslinking agent on poly(butylene adipate-co-terephthalate): Preparation, characterization, and performances

In this work, we performed green processing of Couroupita guianensis carbon nanoparticle (CNPs). The plants of Couroupita guianensis have been carbonized at successive temperatures at 700 °C for 2 h. Solution casting methods was performed for the fabrication of poly(butylene adipate-co-terephthalate) (PBAT) nanocomposites via addition of 0.5, 1.0, 3.0, and 5.0 wt% of CNPs to PBAT and gallic acid (GA) in a 70/30 (w/w) ratio, GA acting as a crosslinking agent. The PBAT-GA/CNPs nanocomposites have been studied with FTIR, XRD, SEM, TGA, and DSC. Barrier (O2 and H2O), and mechanical (tensile strength and elongation) tests were investigated and compared. The mechanical properties of the PBAT nanocomposites were enhanced due to the CNPs and GA addition. The nanocomposites with 3.0 wt% CNP added had a tensile strength that was greater than pure PBAT (PBAT-GA filled to 3.0 wt% at 24.19 MPa vs. PBAT filled to 11.22 MPa), which had the least tensile strength. The smallest, WVTR and OTR values have been observed in the PBAT nanocomposites with 5.0 wt% CNPs filler added. The 5.0 wt% CNPs added film exhibited the greatest barrier property. Increased antimicrobial activity has been shown by the PBAT-GA/CNPs nanocomposites against the microorganisms that are pathogenic to foods (S. aureus and E. coli). In addition, according to the results on food quality test, PBAT nanocomposites were used to exceed the performance of commercial polyethylene (PE) film in increasing the shelf-life of edible grapes from 1 to 15 days. The results of the study suggested that PBAT loaded nanocomposites with GA and CNPs could be good choices for uses in food packaging.

SiO2 Nanoparticle Coating to Enable Polyethylene-Based Na-Ion Battery Separators

The increasing demand for Li-ion batteries (LIBs), pushed even more by the electrical vehicle industry, has highlighted the concern with the scarcity and uneven distribution of LIB raw materials. Electrochemical energy storage based on alternative chemistries, once properly developed, may provide sufficient energy density to partly supply that demand, reducing the dependence on Li natural reserves. Among the studied chemistries, Na-ion-based storage is currently attracting a lot of research attention. This is partly due to the similarities between Li and Na, which allow for the utilisation of analogous materials and methods already in place for LIBs. However, not every component of LIBs can be directly applied to Na-ion batteries (SIB).[1] This is the case for battery separators, the membranes used to avoid physical contact between the two battery electrodes to prevent short circuiting while conducting ions from one battery pole to the other. Porous polyolefin films, such as polyethylene (PE) and polypropylene (PP), have been successfully used in LIBs, but are not compatible with SIB electrolytes. In the latter case, issues arise from the poor wettability of the separator with the electrolyte, which leads to low ionic conductivity, and creates an uneven flux of ions that can cause cell failure. To address this issue, previous reports have shown that the presence of inorganic oxides such as ZrO2 [2] and SiO2 [3] on polyolefin films can increase the affinity of the separator with commonly used LIB and SIB electrolytes. Moreover, ceramic-modified films also show higher thermal stability and hindered thermal shrinkage, which improves battery safety.In this work, we investigated PE coated with spherical SiO2 particles (designed by Glantreo, Ireland) with different sizes of 85 and 200 nm. The coatings were made by tape casting both sides of a PE film with slurries containing SiO2 particles and a binder. Binder type, SiO2 concentration and SiO2/binder ratio were optimized for each particle size. The obtained films were characterized by scanning electron microscopy and infrared spectroscopy, and were compared regarding their wettability, thermal stability, and ionic conductivity. The films were tested as separators in hard-carbon half-cells with 1 mol/L NaClO4 in either diethylene glycol dimethyl ether (DEGDME) or ethylene carbonate (EC)/ propylene carbonate (PC) electrolyte. With carbonate-based electrolyte, PE has very low wettability and cells short circuit within the first cycle. However, SiO2-PE samples showed higher wettability, which allowed for cycling at low current densities. In DEGDME-based electrolyte, cells with PE separator presented capacity fade, with 50% capacity loss after 250 cycles at 400 mA/g. On the other hand, cells with SiO2-PE separator had stable cycling for more than 300 cycles and no short-circuiting was observed, even when high active mass loading electrodes (8 mg/cm2) were used. These are promising results showing that a surface layer of SiO2 particles can make PE a viable option for SIB separators.

Melon management using agrotextile and plasticulture and its prospects for Roraima

The melon (Cucumis melo L.) is a crop of great economic importance for the world, and in Brazil it is mainly intended for the export of its fresh fruits to the European market. In the North region, especially in Roraima, the cultivation of melon is one of the alternatives for exploring the cerrado areas, as its favorable edaphoclimatic conditions enable cultivation during the off-season in Brazil. The yellow melon is grown by most producers in Roraima, however, the technology adopted by the producers implies low yields and quality of the fruits required by the foreign market. The Northeast region of the country adopts techniques for the use of mulching (soil cover using polyethylene film), where beneficial factors are associated with curcubitaceae, protecting the soil against evaporation, saving water, energy, fertilizers and hindering pest infestation. (weeds and insects), and diseases. In addition, they use agrotextile to cover plants, which reduces the attack of pests and diseases in the melon crop. Thus, proper management provides good perspectives for the cultivation of melons with excellent quality, reducing the use of pesticides and being profitable for the producer. Therefore, in view of this context, this study sought to review inherent information on the efficiency of the use of mulching management associated with TNT in the melon crop.

Antimicrobial potential of linear low-density polyethylene food packaging with Ag nanoparticles in different carriers (Silica and Hydroxyapatite)

Silver nanoparticles incorporation into polymeric packaging aims to prevent microbiological contamination in food products, thus ensuring superior food safety and preservation. In this context, this study aimed to verify the antimicrobial efficacy of linear low-density polyethylene (LLDPE) films incorporated with silver nanoparticles (AgNPs) dispersed in silica (SiO2) and hydroxyapatite (HAP) carriers at different concentrations. AgNPs + carriers polymer films were characterized at 0.2, 0.4, and 0.6% concentrations using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission gun-scanning electron microscope (FEG-SEM), thermogravimetric analyzer (TGA), differential scanning calorimetry (DSC), and migration in acidic and non-acidic simulants. Antimicrobial action was investigated on Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and the Penicillium expansum and Fusarium solani fungi with antimicrobial activity by direct contact test and bacterial imaging by scanning electron microscopy. AgNPs addition to the LLDPE matrix did not interfere with the films' chemical and thermal properties and presented no significant migration to the external medium. For antimicrobial action, silver nanoparticles showed, in most concentrations, an inhibition percentage higher than 90% on all microorganisms studied, regardless of the carrier. However, a greater inhibitory action on S. aureus and between carriers was found, making hydroxyapatite more effective. The results indicated that nanostructured films with AgNPs + hydroxyapatite showed more promising antimicrobial action on microorganisms than AgNPs + silica, making hydroxyapatite with silver nanoparticle potentially useful in food packaging, improving safety and maintaining quality.

A compact meander flexible UHF tag for industrial applications

The objective of this paper is to introduce a novel design for a flexible Ultra-High Frequency tag (UHF tag) through the utilization of the meander line technique (MLA) and loop antenna method. The primary goal is to achieve a compact UHF tag operating at 868 MHz. The physical dimensions of the UHF tag are 110×12×0.1mm3. The proposed UHF tag is manufactured using the inkjet printing method on a polyamide substrate featuring a relative dielectric constant of 3.5, a tangent loss of 0.0027, and a height of 0.0508 mm. Through electromagnetic simulation and validation, the functionality of the proposed UHF tag covers the UHF band ranging from 854.57 to 883.89 MHz, with a bandwidth of 29.32 MHz. The reflection coefficient at 868 MHz is approximately -22.46 dB. The simulated gain measures 1.79 dBi, while the theoretical read range is estimated at 5 m. The UHF tag is produced using silver ink with a thickness of 0.05 mm and assembled using an anisotropic conductive paste (ACP). Subsequent to electromagnetic simulation, the UHF tag’s performance is confirmed through a reading test conducted with a radio frequency identification (RFID) base station. The results are consistent with the theoretical expectations, showcasing a commendable read range of 5 m. To safeguard the UHF tag from challenging environmental conditions, it is enclosed within a polyethylene film (PE). Following encapsulation, the read range decreases to 3 m, making it suitable for RFID applications requiring mid-range capabilities.