Polyethylene Sheets Research Articles

Growth and yield responses of fluted pumpkin (Telfairia occidentalis hook F.) to mulching and varying seed sizes in Nsukka Enugu State Nigeria

This experiment studied the effects of seed weight and mulching material on the growth and productivity of fluted pumpkin (Telfairia occidentalis), an important leafy vegetable crop widely cultivated in southern Nigeria. The study aimed to optimize the conditions for improved fluted pumpkin cultivation in Nsukka area of Enugu State, Nigeria. A field experiment with a 2 x 3 factorial in randomized complete block design (RCBD) was conducted to evaluating two factors: seed weight (1-9.9g vs >10g) and mulching material (dry grass, black polyethylene sheet, and no mulch). Parameters measured included vine length, number of nodes and leaves, vine girth, survival count, and above-ground biomass at 5, 7, and 9 weeks after planting. The results showed that while mulch type did not significantly influence the measured agronomic parameters, seed size had a considerable impact. Larger seeds (>10g) consistently outperformed smaller seeds across all growth parameters, with significant differences observed in survival count and vegetative traits. The interaction effects revealed synergistic benefits when combining larger seeds with polyethylene mulch, enhancing leaf production, node development, and vine extension. Additionally, the combination of larger seeds with shredded grass mulch boosted vine girth and biomass accumulation, likely due to improved soil moisture conditions. The study recommends utilizing larger Telfairia seeds (>10g) in combination with shredded grass mulch to maximize vegetative growth development and yield. These findings provide practical recommendations to local farmers for optimizing seed quality and mulching practices in fluted pumpkin cultivation in Nsukka and regions with similar agro-ecological conditions.

EFFECT OF EROSION CONTROL METHODS ON THE SOIL PHYSICAL PROPERTIES AND YIELD OF ONION IN KABBA, NIGERIA

Field experiments was conducted at the Horticultural Section of Kabba College of Agriculture, in Kabba, Kogi state, Nigeria in 2021 and 2022 seasons. The experiment was laid out in a 6 x 2 factorial in a randomized complete block deign (RCBD). The two factors evaluated were erosion control method and cultivar of onion planted. The erosion control method used were A1= plough + harrow + ridge (P+H+R) (conventional method), A2 =Plough + Harrow twice + plastic polyethylene(sheet cover) (P + H2+ PS), A3 = Plough + Harrow + mulches (P+H+MS), A4 = plough + Harrow twice with raise edges (P+H+RE),A5 = Strip cultivation of onion and cowpea (Strip) and A6 = Use of herbicide (Herb). The varieties of onion used were B1 = Red creole (red) and B2 = white creole (white). Data collection on agronomic parameters includes plant height (cm), number of leaves per plant, crop growth rate and onion yield. Soil physical properties observed were soil bulk density, soil moisture content and soil porosity. From the result of the experiment, plots with mulch materials either polyethylene or grass was better than non- mulch plots. However, erosion control method Plough + Harrow + mulches (A3) gave the highest onion yield (8.67 t/ha). Also, variety B2 gave a yield of 8.78 t/ha better than variety B1. For Optimum production of onion, farmers should grow variety B2 and control soil erosion using erosion control Plough + Harrow + mulches.

Quantitative Effects of Ecuadorian Silicon-Aluminum Materials on the Degradation Rate and Mechanical Strength Enhancement of Recycled Polyethylene

This study presents an innovation in the use of a native Ecuadorian nanoporous material known as allophane for the reprocessing of greenhouse plastics to obtain a functional polymer that allows for reuse, improving its mechanical properties and/or increasing its lifespan. By achieving this objective, three problems are simultaneously addressed: 1) the need to recycle used plastics in a prominent Ecuadorian flower company committed to environmental preservation, 2) the scientific viability work carried out by the Central University of Ecuador, and 3) the industrial application of recycled plastics and pellet production. Blown film extrusion was used to prepare low-density polyethylene sheets with different amounts of Ecuadorian allophane microparticles (30±5 micrometers) (0.1%, 0.3%, and 0.5% by weight). Mechanical property studies were conducted following ASTM D 882 standards, and thermal stability was characterized using thermogravimetry. The results showed an increase in elongation at break and Young's modulus percentages as the concentration of the additive increased, demonstrating its physical-chemical compatibility. Additionally, the effect on the polymer’s thermal degradation was analyzed, resulting in a directly proportional relationship between activation energy and the concentration of the material. Finally, these results demonstrate that allophane as an additive enhances the mechanical properties of recycled low-density polyethylene (12-36%) and accelerates its thermal degradation process, reducing environmental impact.

Single-screw extrusion performance for LLDPE resin as a function of compression ratio

High-quality polyethylene film and sheet must be free of solid polymer fragments and degraded resin. Moreover, the products must be produced at high rates to minimize conversion costs. Thus, the extruder must produce a homogenous extrudate at the proper discharge temperature and pressure. The screw design and process operating parameters are key. A key screw design parameter is the compression ratio. This paper experimentally studies how the compression ratio affects a linear low-density polyethylene (LLDPE) resin extrusion process. A 2.8 compression ratio screw was optimal for LLDPE resin. Significant solid polymer fragments were observed in the extrudate for 2.8 to 3.6 compression ratio screws at 110 rpm and higher. For 2.0 and 2.4 compression ratio screws at less than 50 rpm, the internal pressures in the extruder were relatively low. At screw speeds 50 rpm and higher, the specific rates for all screws were higher than the calculated specific rotational rate, creating negative axial pressure gradients in the metering sections.

Passive sampling of polycyclic aromatic hydrocarbons with low-density polyethylene: Equilibration limitations in aqueous suspensions

Polyethylene (PE) and other polymers are widely and successfully used as passive samplers for organic pollutants in the environment. This study provides high-resolution experimental data from batch shaking tests on the uptake, reversibility, and linear equilibrium partitioning of polycyclic aromatic hydrocarbons (PAHs) using two different PE sheets of 30 µm and 80 µm thickness. Kinetics for phenanthrene are well described by a mechanistic first-order model with mass transfer limited by an aqueous boundary layer (with a mean thickness of 170 µm). Equilibration in laboratory batch systems during uptake and desorption is very rapid with characteristic times of 1–2 h but this depends on the boundary condition, e.g., the ratio of PE mass to water volume. Therefore, equilibration of PE in other setups, e.g., in soil slurries or sediment suspensions, may take orders of magnitude longer because the boundary condition for PE changes from finite to infinite bath conditions (soil or sediment particles may keep the concentration in water almost constant). Solid precipitates for high molecular weight PAHs explain partition coefficients below expected values because of kinetic limitations in such a system. Nevertheless, passive sampling can be employed safely if such limitations are considered; furthermore, partition coefficients can be estimated accurately by empirical relationships (e.g., within 0.1 log unit) based on molecular weight, octanol/water partition coefficients, or subcooled liquid solubilities.

Effect of Triton X-100 surfactant concentration on the wettability of polyethylene-based separators used in supercapacitors

Polyethylene-based separators are generally unsuitable for aqueous supercapacitors due to their poor wettability with the electrolyte, which impedes ion transport. However, incorporating Triton X-100 (2-[4-(2,4,4-trimethylpentan-2-yl)phenoxy]ethanol) into the aqueous sulfuric acid (H2SO4) electrolyte improves the wettability of polyethylene and facilitates ionic movement through its pores. In this study, Triton X-100 was added to 1.0 M H2SO4 at various concentrations (0.122%–1.210% V/V) to evaluate its impact on supercapacitor performance. Supercapacitors were assembled using activated carbon-filled carbon cloth electrodes, each of the above electrolytes and polyethylene sheet separators. Scanning electron microscopy revealed that the carbon cloth exhibited a uniform fiber distribution and high surface area for activated carbon integration. The polyethylene separator displayed a porous structure with an average pore size of 165 ± 35 nm. Triton X-100 significantly reduced the water contact angle from 101.5° (without surfactant) to 30.2° (with 1.21% V/V Triton X-100), enhancing polyethylene’s wettability. This change from hydrophobic to hydrophilic characteristics enabled the formation of an electrical double layer at the separator/electrolyte interface, improving ionic transport. However, higher Triton X-100 concentrations increased the electrolyte's viscosity, which impeded ion movement. The highest specific capacitance of 55.3 F/g (at a scan rate of 0.005 V s−1) was achieved with 0.488% V/V Triton X-100. The specific capacitance varied with surfactant concentration in a complex manner, influenced by micelle formation and precipitation. These findings were corroborated by cyclic voltammetry and AC impedance spectroscopy.

Salinity Studies in Quinoa (Quinoa Chenipodoum Willd) from Haditha Desert, Western of Iraq

The present studies were conducted to determine the effect of various concentrations of NaCl salinity on germination and growth of four genotypes of Quinoa Chenopodium Willd, namely G1 (KVL-SR2), G2 (Q-21), G3 (Q-37), and G4 (Regalona), exposed to 0, 60, 120, and 300 mM NaCl. The study was conducted at the Center of Desert Research, Egypt, and the experiment was carried out in the Plant Physiology Laboratory of the Center of Desert Studies. Seeds were treated with four different levels of NaCl concentration: 0, 60, 120, and 300 mM. The experiment followed a Completely Randomized Design with three replications. The germination experiment aimed to determine the effect of NaCl salinity on seed germination percentage. Seeds were placed in autoclaved petri dishes lined with two layers of filter paper, with fifty seeds per dish. Seeds were treated with 0, 60, 120, and 300 mM NaCl solutions (5 mL). The petri dishes were kept in the laboratory at temperatures ranging from 25°C to 28°C for four weeks. Water loss from the petri dishes due to evaporation was monitored using control petri dishes, and water was added every 24 hours as needed. A pot experiment was conducted using plastic pots containing 1700 grams of fine-sieved soil. Seeds of the aforementioned genotypes were sown in 500 grams of soil, separated from the rest of the pot's soil by a polythene sheet. Plants were watered on alternate days and subjected to salinity treatment 25 days after sowing. Fifty milliliters of nutrient solution (N ratio of 6:4) were also added to the salt solution per pot. The salt solution was applied to the 1200 grams of soil in the pot, and after complete absorption, the polythene sheet separating the soil containing plantlets was removed, allowing the roots of the seedlings to grow into the saline soil in the lower half of the pot. Thinning was done after one week, maintaining five plants per pot. The plants were harvested one month after the salinity treatment. It was observed that the germination percentage decreased as the salinity level increased. G1 was tolerant, while G4 was salt-sensitive compared to the other genotypes. Plant height, number of leaves, and number of nodes per plant decreased with increasing salt concentration. G3 was least affected, followed by G2, G1, and G4. Fresh weight, dry weight, and percentage water content of the plants also significantly decreased with increased salinity. The distribution of Na+ ions in various plant parts showed a high concentration in the roots, stem, leaf blade, and leaf sheath of all genotypes. The highest concentration of Na+ ions was found in the leaf sheath of all genotypes, followed by the stem, root, and leaf blade, with high water content even under the highest salt levels. An effective partition of Na+ and Cl- ions in the leaf sheath and the transport of K+ to the physiologically important leaf blade were observed in G1, while other genotypes did not exhibit this efficiency. The specific ion effect of NaCl on the total N status of plants was most pronounced in G1, followed by G2 and G3, while G4 maintained optimal N levels in the root and leaf blade. The tolerant genotype G1 could be utilized for rehabilitation in salt-affected areas.

Study of Factors Affecting UV-Induced Photo-Degradation in Different Types of Polyethylene Sheets.

Enhancing the degradability of polyethylene plastics could provide a potential solution to the overwhelming crisis of plastic waste. Conventional studies have focused on the degradation of polyethylene thin films. This study investigated UV-induced photo-degradation according to ASTM D5208-14 in polyethylene sheets with thicknesses ranging from 0.4 to 1.2 mm. The impacts of sample thickness, metal pro-oxidants, polyethylene resin types and foaming were explored through the characterization of the carbonyl index, molecular weight, tensile properties and crystallinity. As pro-oxidants, single iron or manganese stearate demonstrated a concentration-dependent trend in accelerating the photo-degradation of polyethylene sheets. The thickness, foaming and resin type-such as low-density polyethylene (LDPE) and high-density polyethylene (HDPE)-significantly impacted the rate of photo-oxidation. Thick polyethylene sheets (1.2 mm) exhibited a heterogenous and depth-dependent degradation profile. As the photo-degradation progressed, the enhanced crystallinity, reduced UV transmittance and formation of crosslinks were able to prevent further oxidative cleavage of the polyethylene chain. This study investigated the time course and factors affecting the photo-degradation of polyethylene sheets, which could provide insights into the formulation design of photo-degradable polyethylene plastics.

The evaluation of the effects of different curing methods on concrete

This research explores the impact of various curing methods on the water absorption and compressive strength of concrete. To evaluate these properties, 45 cubes of mix ratio 1:2:4 were tested under different curing methods namely water ponding, sand, polythene sheet coverage, sawdust and water sprinkling. All the cubes were cured at an average laboratory temperature. Water absorption, compressive strength and SEM-EDX tests were conducted on the concrete cubes after curing for 7, 14 and 28 days. The study found that the water absorption and compressive strength values at 7, 14, and 28 curing days ranged from 1.53 to -1.12% and 21.30 to 31.40 N/mm2, respectively and varied depending on the curing method used. All the cementitious compositions of the concrete cubes of all the curing methods showed an increase with the increase in curing age and ranged between 0.01 and 81.67, while their SEM images revealed heterogeneous microstructures consisting of aggregates, cement paste, and voids.Sand and sawdust curing produced the highest and lowest compressive strength values, respectively. Based on these findings, sand curing was identified as the most favourablemethod. Further investigation should be carried out.

Selection and modification of thermoplastic polymer films for orthotonology

The possibility of using thermoplastic polymer films low density polyethylene and polyethylene terephthalate of domestic marks for the production of elixirs and soft molds intended for polymerization of dental composites used in orthodontics was established. The supramolecular structure and composition of the low-density polyethylene and polyethylene sheets of domestic brands, as well as their mechanical properties are different from the structure and properties of Shueu-Dental’s signature polymer materials. The difference in composition and degree of crystallinity of the sheets is determined by differential scanning calorimetry. The base of soft films for matrices is low density polyethylene with a crystallinity of 35±5%, and the base of hard films for the manufacture of elixers is an amorphous copolymer of ethylene terephthalate with a glassing temperature of 76-81 оС. The deformation properties of imported low density polyethylene are similar to the properties of domestic polymers of various brands. The deformation properties and crystallinity of imported polyethylene terephthalate are significantly different from those of domestic brands, which are similar in composition for the conformity of the polymer materials of Shueu-companyDental and domestically produced films produced modified heat treatment of domestic materials in the muffler furnace. By selecting the temperature and time of heat treatment of polyethylene terephthalate sheets, a material with reduced crystallinity is obtained without the content of «volatile» components. The suitability of a modified plastic terephthalate plate of domestic production for the manufacture of the aligner was tested by measuring its rigidity. Hardness was estimated by the size of the module Jung measured by stretching samples of original and modified materials at constant stretching speed. After the modified heat treatment, the degree of local pull and diversity of finished products (liners) made of low-density polyethylene and polyethylene terephthalate were investigated. Measured thickness at characteristic points and established a quantitative relationship between the thickness of the products and the degree of extraction of polymers used in orthodontics.

Synthesis of amidoxime adsorbent prepared by radiation grafting on upcycled low-density polyethylene sheet for removal of heavy metals from wastewater

The issue of discharging waste, especially heavy metals from industrial activities into the environment, not only adversely impacts environmental quality but also has impacts on communities and human health. Removal and reduction of heavy metal contamination in rivers and wastewater are, therefore, critical initiatives that require significant attention. This work studied the removal of heavy metals, including Zn(II), Cu(II), As(III), and Pb(II) by utilizing an upcycled amidoxime low-density polyethylene sheet (AO-sheet). The synthesized AO-sheet was analyzed for various physical properties, including scanning electron microscope, energy-dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. For the batch adsorption experiment, parameters affecting adsorption capacity were studied: initial concentration, submerging time, and pH. Adsorption isotherms were also studied. The results of the heavy metal adsorption study showed that the initial concentration was the most significant parameter; the higher the initial concentration, the greater the adsorption capacity. The adsorption capacity of Zn(II) and Pb(II) increased with submersion time, which achieved 21.07 and 0.855 mg/g-adsorbent, respectively, after four weeks of submersion under the highest initial concentration studied. The adsorption capacity of Cu(II) was 7.98 mg/g-adsorbent after two weeks of optimal adsorption duration under the highest initial concentration studied. The adsorption capacity of As(II) was 1.07 mg/g-adsorbent after one week of optimal submersion time under the highest initial concentration studied. Moreover, the appropriate pH range for effective adsorption of Zn(II), Cu(II), and Pb(II) was identified as 8–9, while for As(III), it was 6–8, with an adsorption duration of 0.43 weeks (3 days). From the Langmuir isotherm, it was found that the adsorption of this work was characterized by monolayer adsorption. The results demonstrate that the AO-sheet can be effectively used to remove heavy metals from wastewater. Its potential for reusability was up to 8 cycles, with the Zn(II) adsorption capacity being reduced to about 20.37%.

UK Museums and Heritage Sustainable Packing Group: Exploring Sustainable Strategies for Soft Wrapping Paintings

ABSTRACT This paper explores methods to improve the sustainability of packing artworks, focusing on soft wrapping of framed paintings. In 2022, the UK Museums and Heritage Sustainable Packing Group was formed. The research described in this paper focuses on one aspect of the group’s activity: seeking to find materials and methods which reduce environmental burdens and comply with conservation standards for soft wrapping two-dimensional artworks for short journeys between display, storage locations and conservators’ studios. The project investigated the physical qualities of recycled content polyethylene (PE), bioplastics and paper-based alternatives, along with common barrier materials such as virgin PE sheet and Bubble Wrap®, to form comparative datasets. Each material’s environmental impact, potential for reuse, interaction with artworks and ability to maintain adequate buffering against environmental changes during transport was researched. Alternative methods were also explored to reduce the quantity of sealing tape and promote its reversibility and reuse. The environmental impacts of the materials were assessed by sustainability specialists at the University of Manchester’s Sustainable Materials Innovation Hub. Reusable and recycled content films offered the most promising alternatives to the PE wrapping most used at present. The use of a tying method, eliminating the need for adhesive tape, also showed potential for further investigation. The low-cost testing methodology should be refined to better control the variables and allow for more repeatable testing, but these preliminary results will help to refine future research directions.

Performance study of solar tunnel dryer for medicinal plants

A solar tunnel dryer is a poly house framed structure covered with UV-stabilized polythene sheet, where agricultural and industrial products on large scale could be dried under at least partially controlled environment. A solar tunnel dryer accelerates and improves the drying process, it protects the product from insects and other pests-infestation thereby, reducing the contamination or product loss. As a result, the solar tunnel dryer lowers post-harvest losses compared to traditional sun drying. In this study, Adhatoda vasica and Moringa oleifera leaves were dried using a simple, low-cost solar tunnel drier and then it was compared with the open sun-dried products. The drying efficiency and the pick-up efficiency of the solar tunnel dryer for the drying of medicinal plant leaves was found to be 12.14% and 26.45%, respectively. The total drying cost of Adhatoda vasica and Moringa oleifera leaves was calculated as Rs. 16.26/- and Rs.16.87/- per kg, respectively as compared to the cost of sun drying which was Rs.114.1/- and Rs. 135.68/- per kg, respectively. The payback period of the dryer was found to be 1 year and 20 days.

Effects of two types of surface treatments on the structural elasticity of human fingernails.

The human nail has a three-layered structure. Although it would be useful to quantitatively evaluate the changes in deformability of the nail due to various surface treatments, few studies have been conducted. The effects of two types of surface treatment-a chemically acting nail softener and a physically acting nail strengthener-on the deformability of human fingernails were investigated. The Young's modulus of each plate of the nail samples before and after softening treatment was determined by nanoindentation. The Young's modulus of the strengthener was determined by conducting a three-point bending test on a polyethylene sheet coated with the strengthener. Young's modulus decreased in order from the top plate against the softening treatment time, and the structural elasticity for bending deformation (SEB) of the nail sample, which expresses the deformability against bending deformation independent of its external dimensions, decreased to 60% after 6h of treatment. The Young's modulus of the nail strengthener was 244.5MPa, which is less than 10% of the SEB of the nail. When the nail strengthener was applied to the nail surface, the SEB decreased to 73%, whereas the flexural rigidity increased to 117%. Changes in nail deformability caused by various surface treatments for softening and hardening were quantitatively evaluated successfully.

Design modification of elliptical vessel solar receiver by response surface methodology

Design modification of elliptical vessel solar receiver system by response surface methodology has been carried out. The materials used in this study were locally sourced from Kenyeta Market Enugu, Onitsha Bridge Head Market, and Idumota Market Lagos. These materials were sourced based on categories of components element: support mechanisms made of mild steel plates, bolts, nuts, clamps, and water as heat transfer fluid. The reflector is made of aluminum foil tape while the vessel has a glass cover fitted with bolts and nuts, the receiver is made of copper pipe, aluminum pipe, galvanized iron pipes, and stainless steel pipes. The pipes were fitted into the vessel with chlorinated polyvinyl chloride 3⁄4 joint pipes, and journal-bearing mechanisms. Other features include the tracking system made of light dependent resistance sensors, a direct current motor, a pulley, a belt, an Arduino controller, and a thermal energy storage tank. The lagging material was an expanded Polyethylene sheet. Experimental data were measured with thermocouples, a digital panel, a Uni-T digital anemometer (UT363), and a digital solar power meter (SM206-SOLAR). Matrix Experimental design was used to develop an experimental model for the system. The developed system was tested to investigate the effect of various heat collectors with and without coating on its performance. It was established from the response optimization that the intercept factor was improved by 32.2%. Similarly, the theoretical efficiency was improved by 8.19% while the experimental thermal efficiency was improved by 6.99%.

Plasticlusters: A marine litter microhabitat in a marina of Tunisia, N Africa

Plastic debris is a significant and rapidly developing ecological issue in coastal marine ecosystems, especially in areas where it accumulates. This study introduces “plasticlusters”, a new form of floating debris agglomeration found in the Yasmine Hammamet marina (Tunisia, North-Africa), loosely attached to pontoon ropes around the water surface level. The analysis of two samples revealed that they were formed primarily by average 2.11 mm polystyrene fragments, 3.43 mm fibers, 104 mm polypropylene and polyethylene sheets, and 122 mm decomposing seagrass leaves. They were inhabited by several taxa, including at least 2 cryptogenic and 5 non-indigenous species (NIS). Unlike other plastic formations, plasticlusters provide a novel and potentially temporal microhabitat to fouling assemblages due to their loose and unconsolidated structure which, combined with marinas being NIS hubs, could enhance NIS dispersion. The results of this study raise concerns about the combined ecological effects of debris accumulation and biocontamination inside marinas.

Plastiome: Plastisphere-enriched mobile resistome in aquatic environments

Aquatic microplastics (MPs) act as reservoirs for microbial communities, fostering the formation of a mobile resistome encompassing diverse antibiotic (ARGs) and biocide/metal resistance genes (BMRGs), and mobile genetic elements (MGEs). This collective genetic repertoire, referred to as the “plastiome,” can potentially perpetuate environmental antimicrobial resistance (AMR). Our study examining two Japanese rivers near Tokyo revealed that waterborne MPs are primarily composed of polyethylene and polypropylene fibers and sheets of diverse origin. Clinically important genera like Exiguobacterium and Eubacterium were notably enriched on MPs. Metagenomic analysis uncovered a 3.46-fold higher enrichment of ARGs on MPs than those in water, with multidrug resistance genes (MDRGs) and BMRGs prevailing, particularly within MPs. Specific ARG and BMRG subtypes linked to resistance to vancomycin, beta-lactams, biocides, arsenic, and mercury showed selective enrichment on MPs. Network analysis revealed intense associations between host genera with ARGs, BMRGs, and MGEs on MPs, emphasizing their role in coselection. In contrast, river water exhibited weaker associations. This study underscores the complex interactions shaping the mobile plastiome in aquatic environments and emphasizes the global imperative for research to comprehend and effectively control AMR within the One Health framework.

Synthesis of Hybrid Composites from Bio-Based Fillers: Chicken Feather, Groundnut Shell, Sawdust

Experimental research has investigated the mechanical characteristics and water absorption performance of polyethylene-based composites reinforced with sawdust, chicken feathers and groundnut shells. Composite samples have been produced with preset volumetric ratios (20%, 30%, 40%, and 50%) at 160°C and 25 kN pressure. A compression molding machine was used to produce specimens of composite materials. The findings indicate that the composites exhibit promising mechanical properties, making them potentially suitable for various applications. However, the waste polyethylene sheet was tested for comparison. It displayed a tensile strength of 7.56 MPa, impact strength with an average energy absorption of 0.093 J, and hardness strength with an average energy value of 92.72 J. The water absorbency data showed minimal water absorption for composite samples, indicating their resistance to water penetration. Similarly, the thickness swelling data revealed no significant change in thickness after immersion, demonstrating dimensional stability in the presence of moisture. This article presents the details of these experiments conducted systematically.

Temperature and salt concentration behavior of a compact rectangular salinity gradient solar pond

Design of economical and effective solar ponds which are useful thermal energy storage devices, remains a huge challenge. The present work aims at investigating the thermal performance of low cost mini salt gradient solar pond. The portable pond was fabricated as a rectangular configuration having a volume of 0.5m3. Polystyrene and high density polyethylene sheets were employed for insulating the walls. The top of the pond was covered with a slender glass so that the dust accumulation could be prevented without affecting the absorption of solar radiation. Sodium chloride salt was used as the medium and the three salt gradient regions namely lower convective, non-convective, and upper convective regions were established through injection filling technique. The temperature and salt gradient data were observed experimentally for a period of 20 days at Coimbatore, India. The pond could absorb significant amount of available radiation (around 65%) and the maximum temperature of the pond was observed to be 49oC. Frequent washing of the water surface is necessary to maintain stable salt gradient. Nevertheless, portable pond fabricated with low cost materials exhibited good potential of storing solar energy for solar thermal applications.

Effect of Inorganic and Organic Weed Management Practices on Growth and Economics in Wheat (Triticum aestivum L.)

An experiment comprising twelve treatments viz., Sulfosulfuran 75 WP @ 25 g a.i., Sulfosulfuran 75 WP + Metsulfuran 5 WP @ 32 g a.i. , Fenoxaprop 10 WP @100 g a.i., Pinoxaden 5 EC @ 50 g a.i. Clodinofop 15% propargyl + Metsulfuran 5 WP @ 19.71 g a.i., Halauxifen-Methyl 6.96 % W/W + Pyroxsulam 25% WG @ 19.71 g a.i., Carfentrazone ethyl 20 % + Sulfosulfuran 25 % WG @ 100 g a.i. each ha-1 at 30-35 DAS, Paddy straw within two rows @ 6.0 t ha-1 , Polythene sheet within two rows both at 8-10 DAS, Hand weeding (20 DAS and 40 DAS), Weed free, Unweeded Control was conducted in randomized block design with 3 replications at Crop Research Farm, Nawabganj, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (Uttar Pradesh) in wheat cv. K 1006 during Rabi 2019-20. The growth characters plant height, number of effective tillers m-2 and dry matter accumulation (g m-2) at 30, 60, 90 DAS and harvest of the crop and economics [Cost of cultivation (₹ ha-1), gross income (₹ ha-1), net income (₹ ha-1) and B:C ratio] of the treatments were recorded. The maximum plant height (28.60, 70.95, 91.65 and 104.65 cm), maximum effective tillers m-2 (184.64, 397.24, 427.76 and 418.23) and dry matter accumulation (98.60, 387.42, 748.34 and 1191.34 g m-2) at above successive crop growth stages were recorded under weed free practice. However, the net return (Rs. 60776 ha-1) and B: C ratio (1.45) was higher with the use of polythene sheet. Thus, mulching with polythene sheet could be exploited as cost effective practice for sustaining wheat production.