Plastic Sheet Research Articles

High plasticity mechanism of high strain rate rolled Mg-Ga alloy sheets

• The mechanism of high plasticity of Mg-Ga alloy is revealed. • The activation of the non-basal slip leads to the high plasticity of Mg-Ga alloy. • Ga element can promote the activation of the non-basal slip • HSRR is the application of dislocation engineering in wrought magnesium alloys. By observing the microstructure evolution of Mg-Ga alloy during tensile deformation, it is found that the prismatic < a > slip and the pyramidal < c + a > slip occur during the tensile process at room temperature, which finally leads to the plenty of dislocation accumulation. After 8% tensile deformation, the { 10 1 ¯ 2 } extension twin is the main way to coordinate the strain in the c-axis direction for the alloy with the Ga content lower than 2 wt.%, but the pyramidal < c + a > slip is the main way to coordinate the strain along the c-axis direction for the alloy with the Ga content higher than 2 wt.%. The Ga addition can promote the activation of the non-basal slip, which is beneficial to the work-hardening of the alloy to achieve better plasticity. Dynamic precipitation can slightly reduce the increment of dislocations. The preparation method of high strain rate rolling (HSRR) is another important reason for the plasticity of magnesium alloy sheets, and it is an important embodiment of the application of the dislocation engineering concept in magnesium alloy. The non-basal dislocations derived from the HSRR deformation can provide the non-basal dislocation sources when magnesium alloy is deformed at room temperature, resulting in good ductility. This study can be used as a reference for preparing wrought magnesium alloy with high strength and high plasticity by Ga alloying and hot deformation. The initiation of the prismatic <a> slip and pyramidal <c+a> slip is the reason for the high plasticity of Mg-Ga alloy, and the Ga element can promote the activation of the non-basal slip. In addition, high strain rate rolling (HSRR) is another important reason for the high plasticity of magnesium alloy sheet, which is the embodiment of the application of dislocation engineering in wrought magnesium alloys.

Edge rippling and petal shape of lilies

Ripples arise along flower petal edges of the species, Lilium casablanca, likely due to differential growth rates at the edges. Torn plastic sheets also exhibit edge ripples analogous to lily ripples. In both cases, the ripples are a consequence of excess edge length. Using both time-lapse videos of blooming lilies and still images of torn plastic sheets, we find that ripples in both systems are well-described by a scaling relationship where ripple amplitude is proportional to an expression dependent on ripple wavelength and arc length.

Mechanical Analysis of Laminated Structures Consisting of Denim Fabric and Recycled HDPE / LDPE Bottle Caps

Industrialization and the increase in population in the world have led to a great increase in the amount of solid waste. Plastic and textile wastes have an important share among the solid wastes, which include many different waste groups. While the increase in disposable products increases the amount of plastic waste, the understanding of fast fashion is among the most important reasons for the increase in textile waste. In this study, cotton based woven textile wastes (2nd quality denim fabric) are laminated with plastic packaging wastes (high density polyethylene (HDPE) and low density polyethylene (LDPE) water bottle caps) in various sequences and thickness, areal density and fiber weight ratio values of these structures are examined. In addition, the impact properties of the produced laminated composite structures are analyzed via drop-weight impact testing machine. The results show that the increase in the number of fabric layers contributes positively to the energy absorption rate thus the samples including two layers of fabrics and one layer of either LDPE or HDPE plastic sheet have the highest maximum loads and absorbed energy values. In addition, it is also seen that HDPE lamination results in higher absorbed energy values compared to LDPE lamination.

Reliability and limitations of GPR for identifying objects embedded in concrete – Experience from the lab

This paper presents laboratory application of the Ground Penetrating Radar technique on six concrete specimens, with intentionally embedded objects made of different materials, in an effort to demonstrate the capabilities of the radar technique and to assist practitioners in using this technique in real applications.Conclusions are drawn on the effectiveness in identifying objects including rebars and (dense) mesh, polyethylene, steel and plastic tubes, steel sheets, wood and brick. The impact of data acquisition parameters is discussed and practical guidance is given for high-quality scans and data interpretation.It is concluded that cross-polarized antennas are an efficient way for the detection and identification of different rebar diameters. The signal penetrability is reduced for moist concrete; however, by suitable signal modification, the raw data quality can be considerably enhanced. The use of the technique for the investigation of laboratory concrete specimens with known content allows for the understanding of the limits of the technique.

Development of an Innovative Mechatronic Binder Machine

This paper describes the development of a mechatronic punch and bind office machine. Integrating smart technologies in the existing traditional business machines will ease the evolution of these systems, enabling productivity and efficiency. The development of an experimental platform that enables further advances in servitization is required. To increase the binding rate of the office document, as well as to reduce the likelihood of errors, efforts have been made to develop a measuring system that allows the document to be properly measured and specifies the appropriate binding spine at the same time. As a complement, developments have been conducted in a system that enables the verification of the inserted spine. In addition, a system for automated document binding along with an integrated platform that allows the communication between all systems is presented. In both its hardware design and its underlying sensors, the new system has several advantages, providing significant performance improvements and upgradability over existing systems. This alternative comprises a system that enables a variety of sheets of paper, plastic or other materials to be punched.

Numerical and Experimental Studies on Hydro-Forming of a Thin Metallic Disc

This paper deals with the hydro-forming of a flat thin metallic disc to achieve a forward domed disc which will be subsequently adopted to manufacture a rupture disc. The plastic deformation induced by the hydraulic energy is numerically simulated through an isotropic hardening plasticity model using a non-linear explicit finite element analysis (FEA). The variation in disc’s central deformation, thickness, equivalent plastic stress and equivalent plastic strain with respect to the applied hydraulic pressure are determined from FEA simulations. The hydro-forming setup is then designed and manufactured, and the metallic disc is experimented under hydro-forming process. The reduction in thickness due to stretching of the thin disc is evaluated from experiment and simulation and a close agreement is found. This research attempt helped in finalizing the hydro-forming fluid pressure, the feasibility and the accuracy of practically achieving the desired geometry of the metallic disc. The near-fixidity effects on abrupt variation in sheet thickness and plastic strain are well captured through simulations which are very difficult to be studied through hydro-forming experiments.

Microwave pyrolysis of polyethylene terephthalate (PET) plastic bottle sheets for energy recovery

Recovering energy from plastics not only mitigates the energy crisis, but also reduces the environmental pollution. In this study, microwave pyrolysis of polyethylene terephthalate (PET) plastic bottle sheets as affected by sheet size (2.5 × 2.5, 5.0 × 5.0, 7.5 × 7.5 and 10 × 10 mm2), silicon carbide load (20, 25, 30, 35 and 40 g), and pyrolysis temperature (450, 500, 550, and 600 °C) was investigated. The results showed that increases in the sheet size increased the average heating rate (19.99–33.22 °C/min), solid yield (10.33–24.33 wt%), gas yield (15.00–35.67 wt%), recovered energy efficiency (10.16–25.34%) and overall energy efficiency (4.62–14.12%). Increases in the silicon carbide load first decreased and then increased the average heating rate (22.04–104.64 °C/min), whereas increased the solid yield (4.33–25.33 wt%), gas yield (8.00–40.33 wt%), recovered energy efficiency (4.21–25.34%) and overall energy efficiency (2.51–14.12%). Increases in the pyrolysis temperature first increased and then decreased the solid yield (22.33–35.67 wt%), gas yield (24.00–40.00 wt%), and the recovered energy efficiency (22.16–34.35%). The optimum condition was at 10 × 10 mm2 sheet size, 35 g silicon carbide load and 550 °C pyrolysis temperature with 35.67 wt% solid yield, 40.00 wt% gas yield, 34.38% recovered energy efficiency and 18.35% overall energy efficiency. The results presented in this study supply method and data for energy recovery from PET plastic bottle sheets.

Aerosol-generating procedures, how best did anesthesiologists use available personal protective equipment during early COVID-19 pandemic in a tertiary care center of southern India? A prospective cross-sectional study.

Background and Aims:Anesthesiologists are involved in high-risk procedures for transmission of SARS-CoV-2 like aerosol-generating procedures (AGPs). The present study was conducted to assess the compliance toward the use of personal protective equipment (PPE) and proposed modifications in anesthesia techniques to prevent dissemination of the virus among healthcare workers.Material and Methods:This prospective cross-sectional study was conducted during the first wave of the COVID-19 pandemic and included all elective surgeries involving AGPs inside operation theatres and remote areas. Participants were anesthesia consultants and trainees. Trained anesthesia technicians observed and documented all the AGPs and data entry with analysis was done using EPI Data 3.1, SPSS 21.0. Descriptive statistics were reported using mean ± SD for continuous variables.Results:Preoperative COVID-19 test was done in 96.3% of patients. Most (74.8%) of the AGPs were performed by consultants. In our study, compliance for N95 masks usage and hand hygiene was found to be 99.2% and 55.9%, respectively. Avoidance of crowding was followed in only 38.9% during intubation. To contain the aerosol-based spread of virus, modification of anesthesia practices like acrylic boxes (6.4%), plastic sheets (5.5%), video laryngoscopy (39%), rapid sequence intubation (RSI) (42.7%), and 59.3% of deep extubation were incorporated.Conclusion:In our study, we found satisfactory compliance toward usage of N95 masks alone, whereas compliance toward other available PPE and modification in anesthesia practice was found to be unsatisfactory.

Navier Slip and Heat Transfer in a Nanofluid Due to a Stretching/Shrinking Sheet: An Analytical Study

This paper is devoted to the analysis of the heat transfer and Navier’s slip effects in a non-Newtonian Jeffrey fluid flowing past a stretching/shrinking sheet. The nanoparticles, namely, Cu and Al2O3 are used with a water-based fluid with Prandtl number 6.272. Velocity slip flow is assumed to occur when the characteristic size of the flow system is small or the flow pressure is very small. By using the similarity transformations, the governing nonlinear PDEs are turned into ordinary differential equations (ODE’s). Analytical results are presented and analyzed for various values of physical parameters: Prandtl number, Radiation parameter, stretching/shrinking parameter and mass transpiration for the flow and heat transfer. The considered problem is relevant to various physical applications in the field of engineering, e.g., the production of certain materials, the preparation of plastic and rubber sheets and glass blowing. It is shown that the considered nanofluid increases the thermal efficiency. The nanoparticles act as a heater by increasing the solid volume fraction and thermal radiation. Vice versa, they can act as a cooler if the strength of magnetic field is increased. The flow strength decreases by increasing the values of Deborah number.

Comparison between Direct Laryngoscopy with and without Aerosol Box for Intubation in Patients Undergoing General Anaesthesia during COVID-19 PandemicA Randomised Controlled Study

Introduction: The airway management of patients with COVID19 is a high risk task for anaesthesiologists. Several innovations have been born as a result of this problem, including aerosol boxes and clear plastic sheets. Aim: To compare the timing and attempt of direct laryngoscopy with and without aerosol box for intubation in patients undergoing general anaesthesia during the COVID-19 pandemic. Materials and Methods: This was a randomised controlled study was conducted in Parul Sevashram Hospital, Parul University, Vadodara, Gujrat, India from April 2021 to September 2021. A total of 50 patients were randomly divided into two equal groups as group A was intubated with an aerosol box and a macintosh laryngoscope, while group B was intubated with a clear plastic sheet and macintosh laryngoscope. With proper airway precautions and Personal Protective Equipments (PPE) comparative assessment of patients undergoing surgery in general anaesthesia was done. Time to intubate, number of attempts, ease of Endotracheal Tube (ETT) tube insertion, quality of Laryngoscopy view and Cormack Lehane scores were assessed in both the groups. Results: The mean time for intubation was high at 29.72 seconds in group A, while it was 23.16 seconds in group B; the difference was significant. Overall, 20 out of 25 (80%) patients could be intubated in 1st attempt in group B as compared to 15 out of 25 (60%) in group A. Airway visualisation using Percentage of Glottic Opening (POGO) scoring and Cormack Lehane staging were suggestive of better visualisation in group B than group A. Difficulties encountered during intubation like laryngoscopy, glottic visualisation, arm movement restriction, ETT negotiation, and stylet removal were lesser in group A as compared to group B. The incidence of complications like sore throat and airway bleeding were lower in group B as compared to group A. Conclusion: In the COVID-19 era, aerosol box and clear plastic sheets are effective barrier measures for airway management to prevent the anaesthesiologists from the aerosol transmission. But airway management with clear plastic sheet is technically easier than aerosol box.

A COMPARATIVE STUDY TO ASSESS EASE OF INTUBATION WITH C-MAC VS DIRECT LARYNGOSCOPE, WHEN USED FOR INTUBATION WITH CLEAR PLASTIC DRAPES OVER MAYO STAND FOR IN COVID NEGATIVE PATIENTS DURING A PANDEMIC IN RESOURCE LIMITED SETTING

The aim of the study was to assess the time to endotracheal intubation, First-pass success when intubating with C-MAC and Direct laryngoscope with clear plastic drapes over a mayo stand. Standard anaesthesia machine and monitors Drugs for pre-medication &amp; general anaesthesia Anatomical face masks, video laryngoscope with blades 3 &amp; 4 Macintosh blade 3 &amp; 4, endotracheal cuffed tubes, Bougie, Clear plastic sheets, Mayo stand. Mayo stands containment setup is suspended over the patient’s head, neck and chest. The necessary Anaesthesia equipment required for intubation will be kept inside the containment setup. General anaesthesia induced with fentanyl, Propofol &amp; Succinylcholine. C- Mac laryngoscope with appropriate size blade will be kept with Group A patients, while Direct laryngoscope with appropriate size blade will be kept with Group B patients. The mean duration of intubation in secs was longer in Group B compared to group A ( 27.47 sec vs 21.4 sec). Based on the intubation difficulty scale score, Group B had more second attempts needed (26.67%) than Group A 6.67%) and also the second operator required in (16.67% vs 3.33%) Group B compared to Group A (p&lt;0.05). Based on CL grades among Group B vs Group A a statistically significant association was observed in relation to grade 1 (63.33%vs93.34%), Grade2a ( 23.34% vs 3.33%) and grade 2b ( 13.33%vs3.33%). We conclude that intubation with a C-MAC laryngoscope has a better glottis view, takes a lesser duration, and lesser number of attempts required for successful intubation when compared to that of the Macintosh laryngoscopy with a plastic drape on a mayo trolley.

Effect of transparent glass cover material on double slope solar still productivity

Solar water distillation apparatus has been developed for the Thoothukudi coastal people in Tamilnadu, India, where drinking water is rare. This analysis focused on the possibility of employing stretched transparency PVC cover instead of usual clear glass sheet for solar distillation equipment. To increase the evaporative surface area, black cotton cloths with enlarged fibres were placed on the bottoms of stills. When the angle of inclination (13°) was equivalent to that of a glass sheet-covered still, more distilled water was recovered from the clear PVC sheet covered still. The solar still's collector received less sunlight than it might have because of an accumulation of water droplets sticking to the PVC lid. A plastic sheet material with reduced water surface adhesion is the ideal choice, or an anti-water surface adhesion chemical should be sought. Until this is achievable, the preferable cover material will remain traditional glass-covered solar distillation machines.

Mechanical properties of lettuce (Lactuca sativa L.) for horticultural machinery design

Currently, there is a growing need to develop machines that replace human work efficiently and effectively in horticulture with the same sensibility of the human hand, since horticultural foods are notably very fragile to handle and process, especially considering machinery and systems. This work aimed to determine the mechanical properties of lettuce (Lactuca sativa L.) variety Crispa. For that, two methodologies were used in the field of material engineering: one specific for polymers and composites – the standard ASTM D3039 – Standard test method for tensile properties of polymer matrix composite materials (ASTM, 2002a) and the other specific for plastic films – the ASTM 882 – Standard test method for tensile properties of thin plastic sheeting (ASTM, 2002b). The tests were adapted for lettuce samples. The mechanical properties for the leaf and stem of head lettuce (var. Crispa) were obtained with appropriate statistical rigor, which can be considered valid initial estimates for dimensioning mechanisms and systems of machines for horticultural works specialized in lettuce. These properties provide fundamental engineering parameters to design machine elements that interact with biological materials, allowing to develop devices that generate minor damage to biological structures in lettuce.

Luminescent Solar Concentrators: A Review of Nanoengineering Opportunities for Reducing Surface Losses

Luminescent solar concentrators are a lesser-known solar power technology that have the potential to make their way into the constellation of building integrated photovoltaics products. A transparent plastic sheet with solar cells on its edges incorporating luminescent species acts as a wave guide to concentrate light entering through its exposed surface to smaller area photovoltaics. Although they have many advantages, the technology&#x0027;s low efficiency constitutes a major barrier to potential commercialization. While there are several factors contributing to this issue, the low efficiency is largely attributed to the escape cone losses through the light-receiving, large area surfaces. Advances in nanoengineering have provided new, promising ways to reduce these losses. Spectrally selective mirrors, cholesteric mirrors, photonic crystals, asymmetric light transmission interfaces, and quantum dots and dyes with anisotropic emission are all possible solutions that can be engineered at the nanoscale to reduce surface losses and improve overall performance of luminescent solar concentrators. Continued research and improvements in these fields could enable luminescent solar concentrators to become staple products for green buildings.

Thermal boundary layer analysis of MHD nanofluids across a thin needle using non-linear thermal radiation.

An analysis of steady two-dimensional boundary layer MHD (magnetohydrodynamic) nanofluid flow with nonlinear thermal radiation across a horizontally moving thin needle was performed in this study. The flow along a thin needle is considered to be laminar and viscous. The Rosseland estimate is utilized to portray the radiation heat transition under the energy condition. Titanium dioxide (TiO$ _2 $) is applied as the nanofluid and water as the base fluid. The objective of this work was to study the effects of a magnetic field, thermal radiation, variable viscosity and thermal conductivity on MHD flow toward a porous thin needle. By using a suitable similarity transformation, the nonlinear governing PDEs are turned into a set of nonlinear ODEs which are then successfully solved by means of the homotopy analysis method using Mathematica software. The comparison result for some limited cases was achieved with earlier published data. The governing parameters were fixed values throughout the study, i.e., $ k_1 $ = 0.3, $ M $ = 0.6, $ F_r $ = 0.1, $ \delta_\mu $ = 0.3, $ \chi $ = 0.001, $ Pr $ = 0.7, $ Ec $ = 0.5, $ \theta_r $ = 0.1, $ \epsilon $ = 0.2, $ Rd $ = 0.4 and $ \delta_k $ = 0.1. After detailed analysis of the present work, it was discovered that the nanofluid flow diminishes with growth in the porosity parameter, variable viscosity parameter and magnetic parameter, while it upsurges when the rate of inertia increases. The thermal property enhances with the thermal conductivity parameter, radiation parameter, temperature ratio parameter and Eckert number, while it reduces with the Prandtl number and size of the needle. Moreover, skin friction of the nanofluid increases with corresponding growth in the magnetic parameter, porosity parameter and inertial parameter, while it reduces with growth in the velocity ratio parameter. The Nusselt number increases with increases in the values of the inertia parameter and Eckert number, while it decliens against a higher estimation of the Prandtl number and magnetic parameter. This study has a multiplicity of applications like petroleum products, nuclear waste disposal, magnetic cell separation, extrusion of a plastic sheet, cross-breed powered machines, grain storage, materials production, polymeric sheet, energy generation, drilling processes, continuous casting, submarines, wire coating, building design, geothermal power generations, lubrication, space equipment, biomedicine and cancer treatment.

Preparation of Naturally Colored Biodegradable Plastic Sheet from Raw Jute and Evaluation of its Multifunctional Properties

Preparation of Naturally Colored Biodegradable Plastic Sheet from Raw Jute and Evaluation of its Multifunctional Properties

Preparation of fixed length carbon fiber reinforced plastic composite sheets with isotropic mechanical properties

Preparation of fixed length carbon fiber reinforced plastic composite sheets with isotropic mechanical properties

Organic phosphor doped thermoplastics with ultralong and memorable room temperature phosphorescence different from crystals

Organic room temperature phosphorescence (RTP) crystals have been extensively reported but encounter poor mechanical properties and processing and application flexibility, which inspires much interest in developing amorphous RTP polymers. However, the current RTP polymers are mainly solution-processed films, and their thermoplasticity and shape and size flexibility and retainability as well as RTP properties need to be improved. Herein, we dissolve two classes of carbazole derivatives starting from commercial (CCZ) and self-made (LCZ) carbazole into solution of PMMA and find the solution-processed films show very poor RTP properties, however, when they are thermoplastic processed into plastic sheets, ultralong blue-yellow dual RTP and blue RTP are observed after photo-activation, which are distinctly different from their crystal RTP. These results reveal that thermoplasticizing can not only alter dispersion states but also local environment of carbazole derivatives, enabling LCZ derivative without crystal RTP to also emit ultralong molecular RTP in polymer matrix. Since RTP generation of polymer films requires photoactivation and the photoactivated RTP patterns show ultralong memory effect, promising information storage and anti-counterfeiting is enabled. This work demonstrates that organic hetero-cyclic molecules can exhibit very interesting and unpredictable RTP properties in polymers different from crystals, opening up a vast research space and a simple processing strategy for tuning and/or enhancing RTP properties of organic doped polymers.

Analisis Pengaruh Temperatur Terhadap Sifat Termal dan Gugus Fungsi Proses Thermoforming Material Polivinilklorida

Forming sheet plastic into various new shapes and applications, this plastic is adjusted to the design we want with the help of heat, pressure and molding. The purpose of this study was to determine the energy and heat value released by PVC material with variations in heating and cooling temperatures in the forming unit,to determine the effect of PVC process temperature on thermal properties with DSC tools and to determine the effect of PVC process temperature on functional groups using FTIR tools.The calculation results show that the heat released by the A.1 material is 1,740 Watt and A.2 is 1,938 Watt. The energy received by the cooling water in the 30th minute on specimen A.1 is 5.571 Watt and A.2 is 14,857 Watt with each temperature increase of 0.5℃. The results of the DSC test samples A.1 (defective) and A.2 (good) show that the melting temperature of the two is almost the same, which is around 78oC but there is a difference in Tg (temperature glass) of 0.013 J/goC faster than the A.2 test specimen 115oC (Very nice). The results of the FTIR test samples A.1 (disabled), A.2 (good) showed the highest difference in wavelength up to 8.4% at the wave values of 3749.77cm-1 and 3740.90cm-1.

Replacing glyphosate in the garden

The city of Davis, California, started phasing out the use of glyphosate-based herbicides in public spaces in the fall of 2017. The public works department warned residents that the change might mean more weeds, but complaints still rolled in. City Council member Dan Carson put it bluntly at a public meeting in 2020 when he complained about the medians on city roads: “It looked horrible,” he said. “It looked absolutely horrible.” Davis decided to stop using glyphosate, one of the world’s most widely used herbicides, over concerns that it could be harmful to human health. Instead, workers pull weeds, suffocate them under plastic sheets, steam them with hot water, or burn them with torches. Those methods are more work, adding $400,000 to the city’s annual budget. Gardeners in the US will soon face a similar challenge. Earlier this year, Bayer announced it would remove glyphosate from lawn and garden versions