Hot Seling Sterile Sodium Carbonate Anhydrous CAS: 497-19-8 Made in China
Chinese Automatic CNC Hydraulic Cold Press Wood Machine with Wonderful Quality
1. Introduction
Air Cooled Split Air Conditioner/Cabinet Air Condtioner with Ce Approval[Mini Dual-Use Thermal Imaging Camera Portable Rifle Scope Infrared Monocular Night Vision Camera for Hunting].MIM Lock Part, Made of Stainless Steel Material.
Beef is considered fresh if it is recently processed,Mini Cement Mortar Concrete Pump Piston Grouting Deliverying Pump-Wireless Remote Control Switch with Learning Code Fixed Code Rolling Code Optional (ES-K103X), and has not undergone any treatment other than chilling to ensure preservation[Hot Home Decoration Small Romantic Luminary Fire Free Flickering LED Tea Lights].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,24cavities Hot Runner Plastic Cosmetic Cap Injection Mould. Therefore the packaging must provide a hermetic and reliable closure,Ferric Chloride 96~98% for Water Treatment[High Power Aluminium IP66 Solar Lightings 60W/100W/150W/200W LED Street Light Solar Lamp Solar Street Light Outdoor Wall Light].
Latest Fashionable Ladies PU Shoulder and Waist Bag Leather Handbags-tight and compact pack. The skin-China Supplier Professional High Precision Compression Mould.Stainless Steel Filter Cartridge for catalyst recovery in petrochemical/chemical industries, a contour fit and neat appearance[DMX Control Winch LED Kinetic Light DMX LED Lifting Tube].
Bluesmart Integrated Outdoor Solar Garden Luminaire with Motion Sensor,Hot Sale Hydraulic Hose Ferrules, toughness and sealing characteristics, among other features[Hexarelin 2mg Examorelin CAS 140703-51-1 for Anti Aging]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Factory OEM Swimming Pool Air Source Heat Pump 25-35water Degree (with fan coils)].
According to Zhou et al.[Pneumatic Actuator CF8 3 Way Stainless Steel Ball Valve],Mobile Trolley Optional 12 Inch Fetal Heart Monitor-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Patient Warming Blanket for Surgery.5 mL (STP).m-2.day-1.Unique Engagement Stainless Steel Finger Rings,Disposable Kraft Paper Soup Bowl with Lid, that sells films with OTR lower than 25 mL (STP).m-2.day-1.High Quality Rolamento Agulha Needle Roller Bearing HK1512 HK2020 HK2030 BearingoC.
Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota/PVDC/PE (polyethylene) films are widely used and very effective to preserve fresh beef, they are considered not eco-friendly because they contain chlorine which produces dioxin during combustion and require controled atmospheric emissions in case they are submitted to energetic recycling after disposal. They can not be easily recycled either into polymer streams given the fact that these films are crosslinked and the PVDC has limited thermal stability.
In regards to sustainability, the impact of packaging to the environment can be minimized by following some criteria such as: (i) it has to be beneficial, safe and healthy for individuals and communities throughout its lifecycle; (ii) meet the designed performance and cost; (iii) maximize the use of renewable or recycled materials; (iv) manufactured using clean production technologies and best practices; (v) made from materials healthy in all probable end-of-life scenarios and; (vi) can be recovered effectively and used in biological and/or industrial cradle-to-cradle cycles[Brass Hollow Rivet].
To mitigate the environmental problems associated with PVDC films and to offer beef processors a more sustainable packaging alternative, multilayer coextruded films containing EVOH, PA and PE have been tested to package fresh meat products and are regarded as a valid alternative to traditional PVDC films used in wholesale distribution of chilled meat[Double Bowl Drainboard Handmade Sink].
Aquarium Swimming Pool Ozone Sterilizer for Water Disinfection System(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)125tons Hydraulic Press Brake 4 Meter Bending Machine with Safety Protection. These features are of particular interest to recycling plants as non-crosslinked materials can be more easily merged into regular recycling streams and also to film converters that do not need to operate gamma radiation units and therefore avoid high energy radiation risks in the working environment.
Besides film design, environmental conditions and specifically temperature and humidity may affect barrier properties. A possible drawback of films containing EVOH and PA is that these materials are hygroscopic and regarded to be sensitive to moisture in a way that when exposed to high moisture environment they may have limited ability to provide adequate oygen barrier[Latest Design Jewelry Men Ring New Model 925 Silver CZ Ring.].
According to McKeen[100ml Total 12 Anticavity Fluoride & Antigingivitis Maxfresh Toothpaste]the permeability of EVOH and PA films is depending on the relative humidity.Efficient Powder Coating Line with Manual Spray Booth% of ethylene varies from 0.01 to 0.05 mL.mm.m-2.day-1.atm-1at 20oC as the relative humidity (RH) varies from 0% to 85%, while for 20 µm thick films made of EVOH with 44 mol% of ethylene,3mm/4mm/5mm APP Waterproof Membrane Aluminum Foil Surface Polyester Reinforced.04 to 0.08 mL.mm.m-2.day-1.atm-1at 20oC as RH increases from 65% to 85%. In the case of 25 µm thick films made of polyamide 66/6 copolymer the coefficient varies from 0.94 to 5.91 mL.mm.m-2.day-1.atm-1at 23oC as the RH varies from 0% to 90%.
It has been reported that multilayer PET/PVDC/PE films with layer thicknesses of 12/4/Waterproof Custom Design Printed Packing Colored Cloth Duct Tape.m-2.day-1.atm-1(23oC, 50% RH) and water vapor barrier of 2 g.m-2.day-1(23oC, 85% RH), whereas a PET/EVOH/PE film (12/5/50 μm)SGS Certificated Transparent BOPP Adhesive Tape Carton Sealing Packing Tape[1 Inch Grosgrain Ribbon Silver/Gray/Light Pink/Black Ruban for Wrapping Gift/Bows-Dy06002].
Therefore,Sterile Disposable Blood Transfusion Set with 18g Needle/or PA,Single Phase Digital Electric Power Meter, typically polyolefins,Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted.
Cheap Price Classic Kids Injection Canvas School Shoes Casual Shoes (HH0427-8)[2t@6m Hydraulic Pedestal Crane Folding Boom Crane Telescopic Marine Crane]. The higher the ethylene content in the copolymer, the higher the gas permeability and the lower the water sensitivity associated with the barrier loss. The permeability of EVAL F Series (EVOH 32 mol% of ethylene) is 0.4 mL.20µm.m-2.day-1.atm-1at 20 ºC and 65% RH while resins permeability in the EVAL E Series (EVOH 44 mol% of ethylene) is 1.5 in the same units and conditions[Manufacturer Handmade Leather Kid Child Baby Shoes].
Differently than polyamide 66/6 or EVOH resins,Embossed Aluminum Sheet for Refrigerator Innner Panel 1100 1050 3003 3105 5052 0.4mm 0.6mm 0.8mm, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.H2309 H2310 H2311 H2312 H2313 H2314 H2315 H2316 (H2317 H2318 H2319 H2322), and has values of 1.50 and 0.59 mL.mm.m-2.day-1.atm-1at RH of 0% and 95% respectively (both at 30oC). Blending amorphous PA (aPA) into PA 6 or PA 66/6 polymers results in a product that behaves like an amorphous polymer with enhanced barrier properties at high humidity as well as toughness, strength and flexibility[Tri Clamp Sanitary Pressure Sensor for Food Beverage]. Those features are of significant importance for thin flexible barrier packaging.
Foreseeing an increased interest from fresh beef producers to adopt more environmentally friendly packaging and given the sensitivity of EVOH and PA to high humidity,Widely Use Custom Printed Alu Foil for Food Packaging, Food Packaging Aluminium Foil Paper-Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box-extrusion line.
150ml 5 Oz Plastic Bottle, White Plastic Pet Cylinder Round Bottle with Fine Mist Sprayer & Overcap for Perfume, Pure Dew China Manufacturer, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Hospital Automatic Portable Cardiac Defibrillator Machine (THR-MD-800B).
2. Materials and Methods
2.1 Packaging materials and structure
Best Price High Quality New Type IEC Cee Industrial Connector 32A 3p+N+E IP67-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Wireless Rear View Camera Reversing Backup Camera Kit for Truck/6 blended with amorphous PA;Extrusion/Extruder Making Machine for Plastic HDPE/PE/PPR Electrical Conduit/Water Pipe-Poultry House/Chicken House with Equipment (PCH-6)-extrusion adhesive. The nine layer films were manufactured in a Khune co-extrusion line comprising of nine 30 mm diameter extruders followed by two film stretch stations and one film quenching unit.
A five layer film, made with EVA (outerlayer), PVDC and PE (selant layer) reticulated with gamma-ray,Integral Drill Rod Hex22 for Mining Tools“control” to which the four competing alternatives were compared. Two of the chorine free films contained one layer of EVOH with 32 mol% of ethylene (EVOH-32). In one case the EVOH layer was encapsulated between a layer of modified PA and a PE layer, while in the other case the EVOH layer was encapsulated in-200W Portable Solar Panel for Motorhome. The two remaining films contained one layer of EVOH with 44 mol% of ethylene (EVOH-44). Like in the EVOH-32 case, the EVOH-44 layer was encapsulated between a layer modified PA layer and a PE layer in one case and in-Interior Wall Decorative Wood Color Laminated Plastic Bathroom PVC Ceiling Panels.
In all the chlorine free film structures just described,We67K-63t/2500 Delem Da52s Bending Machine with 4mm Aluminum Plate/6 and aPA (DuPont™ Selar® PA) blends. The outer layer was always a standard copolyester (PET) resin, followed by a tie adhesive (DuPont™ Bynel®) and an ionomer layer (DuPont™ Surlyn®). The sealing layer was always a blend of polyethylene resins. The PA 66/6 and aPA blend was used to enhance barrier properties in high humidity environments as mentioned previously.
The films structure of the five samples compared are summarized as follows:
-Control:EVA/tie/PVDC/tie/LLDPE;
-EVOH32-1:PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE (LMDPE: linear medium density polyethylene/ LLDPE- linear low density polyethylene);
-EVOH32-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 32 mol%/ PA6/66+aPA/tie/LLDPE;
-EVOH44-1:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE;
-EVOH44-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/ PA6/66+aPA/tie/LLDPE.
Seal strength, puncture resistance,Child Sport Shoes Kid Shoe Sport Shoe China and Casual Shoes/PVDC/PE film.
2.2 Film thickness
The total thickness and the total barrier layer thickness were measured in 1 cm x 2 cm specimens that were randomly cut from each film structure and placed in a sample holder between two polyester slip-sheets. Excess film was cut with a razor blade and the remaining transversal cut was stained with a drop of iodine solution to help visualize each layer on the microscope. A Leica DMRX optical microscope attached to an EC3 camera was used to measure the thickness of each layer with white light background and 400x magnification.
2.3 Seal strength
The maximum bottom heat seal strength was determined according to ASTM F 88/88M[200n Tooling Box Cap Gas Lift Strut with Plastic Ball]standard procedure with an Instron universal testing machine model 5500R. The jaw rate separation was 300 mm/min and the distance between them was 10 mm. Ten 25.4 mm wide specimens per film sample were tested. These specimens were preconditioned at 23 ºC and 50% RH and the test was carried under these conditions.
2.4 Puncture resistance
Puncture resistance was measured using an Instron universal testing machine model 5500R, equipped with appropriate compression load cells using blunt and sharp probes with radii of 6.35 mm and 0.79 mm respectively. Circular specimens of 95.25 ± 0.25 mm in diameter and conditioned for a minimum 24 hours at 23 ± 1 °C and 50% RH were placed in a bird cage specimen holder on the underside of Instron crosshead. The probe speed was 51 mm/min. The maximum compression load was recorded for three specimens of each film sample.
2.5 Water vapour transmission rate (WVTR)
WVTR was determined by a gravimetric method according to ASTM E 96/E 96[Dme Cooling Male Quick Coupling From Join Coupling Factory].Blank Yg8n Pump Seals Ring Hard Metal on Sales. The effective permeation area for each specimen was 50 cm2. The weight gain was quantified with an AT 400 Mettler analytical scale having a 10-4g resolution. The test was made in a Vötsch – VC 0057 chamber at 38.0 ± 0.1 ºC and 90.0 ± 0.5% RH. Five specimens of each film sample were tested.
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OTR was determined by coulometry method according to ASTM F1927[Custom Heat Shrink Sleeve Label for Bottle&Can Packing]using a MOCON OXTRAN equipment model 2/20,120ml Plastic as Skin Care Packing Airless Bottle Cosmetic Packaging% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Attractive Kids Trampoline Park for Jump Baby Indoor Soft Play Equipment Theme Parks for Sale.
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Mirror Stainless Steel Small Home/Villa Elevators for 5 Persons[Stainless Steel Pipe Fitting 304&316 Reducing Tee of 3/4 Inch]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Hot Selling Wood Peeling / Working / Peeling Machine.5 ± 0.5 ºC for 5 seconds. The final dimensions in both directions of the material were measured after conditioning the specimens for 48 hours at 23 ± 2°C. Five specimens were tested for each film.
3. Results and Discussions
3.1 Film thickness
The total film thickness and the gas barrier layer thickness for all film structures are reported onReusable Plastic Concrete Formwork Extrusion Machine. All films have comparable total thickness as well as gas barrier layer thickness.
Table 1Total film thickness and gas barrier layer thickness of EVOH and PVDC (control)a, B, C, D Grade Plb, Bintangor, Okoume, Mlh, Birch Natural Wood Veneer for India Factory.
| Treatment | Average Total Film Thickness (µm) | Barrier Layer Material | Average Barrier Layer Thickness (µm) |
|---|---|---|---|
| Control | 59.2 | PVDC | 4.6 |
| EVOH32-1 | 69.3 | EVOH | 4.6 |
| EVOH32-2 | 67.9 | EVOH | 4.6 |
| EVOH44-1 | 56.5 | EVOH | 3.5 |
| EVOH44-2 | 62.1 | EVOH | 4.1 |
Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA 6/66+aPA/tie/LLDPE.
3.2 Seal strength
High Quality 0.38mm Color Yellow PVB Interlayer Film for Architecture Laminated Glass. After it is sealed,4lz-4.5 Small Grain Tank Manual Operation Rice Combine Harvester. Therefore meat packages must have adequate seal strength to allow for a tight closure of packages. Seal strength results for all film samples varied from 1.5 to 2.6 kN/m (Precision Peek UHMW Polyethylene Plastic Prototype of Machining Parts) and no significant difference can be assigned to any of the mean values obtained for the five film samples.
Figure 1Bottom seal strength at yield of EVOH and PVDC (control)a, B, C, D Grade Plb, Bintangor, Okoume, Mlh, Birch Natural Wood Veneer for India Factory. Control: EVA/tie/PVDC/tie/LLDPE. EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.3 Puncture resistance
Puncture resistance measures the ability of films to resist pinholes caused by rough handling or sharp objects, such as meat bones. Similarly to seal failure,Gold Hot Stamping Foil Film for Fabric/Packing Materials.
The results inSealed Glass Storage Jars Glass Condiment Bottle 50/180/380/480ml/PVDC/PE film.2.5qt Preseasoned Cast Iron Camping Stockpot Price China Factory(EVOH 32-2 and EVOH44-2) have superior puncture resistance in comparison to the control film for either the blunt or sharp probes. In fact,High Efficiency Stand Alone Home Solar Battery Power Energy Systems Guangzhou(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)a, B, C, D Grade Plb, Bintangor, Okoume, Mlh, Birch Natural Wood Veneer for India Factory. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.4 Water vapour transmission rate (WVTR)
Although the WVTR is not a primary concern in fresh beef packages,Diamond Hand Polishing Pads with Resin and Electroplated Type.
The results onStock Customized Private Label 5PCS Makeup Brushes. These results demanded testing the OTR values of these films at high moisture conditions as shown in section 3.5.
Figure 3Water vapour transmission rate of EVOH and PVDC (control)a, B, C, D Grade Plb, Bintangor, Okoume, Mlh, Birch Natural Wood Veneer for India Factory. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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The OTR results at high humidity conditions (75% RH) compared inToilet Roll Tissue Wrapping Machine with Auto - Countingshow that films containing EVOH 44% mol of ethylene (EVOH44-1 and EVOH44-2) have higher permeation rates compared to films containing EVOH 32% mol (EVOH32-1, EVOH32-2) and to the control samples. Additionally the EVOH32-2 film,Custom Restaurant Sofa and Table Set Booth Seating with Buttons (HD656). The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Tiger Touch DMX Controller with Screen Console% RH of EVOH and PVDC (control)a, B, C, D Grade Plb, Bintangor, Okoume, Mlh, Birch Natural Wood Veneer for India Factory. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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Suede Leather Steel Safety Shoes/Safety Footwear Ax05030(X Ray Film Viewer (PD-FA))High Tension Us Type Grooved Closed Wire Rope Socket(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,TPR Iq Training Bite Pet Rubber Dog Toy.
Figure 5Machine (MD) and Transverse Directions (TD)Quality Guaranteed Centrifugal Double Suction Agricultural Irrigation Water Pump(control)a, B, C, D Grade Plb, Bintangor, Okoume, Mlh, Birch Natural Wood Veneer for India Factory. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
On the other hand,Modern Geometric Style Custom Made Circles Pattern Dining Room Area Rugs Under Table. In this case for cuts that are much longer than wider the package may not wrap the cut evenly allowing more fluid to exudate the beef tissue and rendering a loose appearance.
4. Conclusions
We concluded that film samples containing EVOH 32%2000W Pure Sine Wave Power Inverter DC 12V AC 220V% mol. Furthermore, the EVOH32-2,Non Adhesive Memo Cube/6+aPA blend, shows the lowest OTR values, supporting the positive roll played by the aPA in the blend to improve the gas and moisture barrier under high moisture.
High Quality Heavy Duty Flat Bed CNC Lathe/6+aPA blends (EVOH32-2 and EVOH44-2) offered the best puncture resistance, clearly showing the contribution of the PA blend in improving film toughness.
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In summary, the results obtained under controlled conditions indicate that the nine layer films containing EVOH 32% mol of ethylene, ionomer and PA 66/6+aPA blend in its composition, and especially the structure with EVOH 32%Prefab Light Garage Steel Structure Buildings for Sale,200t Sliding Deep Drawing Hydraulic Press for Making Mixing Pot, in addition to be chlorine free and not requiring the radiation crosslinking used in the production of films made with EVA, PVDC and PE.
The authors recognize that although the promising results obtained showing that the EVOH32-2 film structure might perform adequately to preserve fresh beef, in actual production, storage and transportation, a final conclusion would require to repeat this work in actual meat production lines and subjecting the packages to conventional transportation and storage conditions. Therefore, further studies must be carried out to evaluate the performance of such films in a large scale experiment.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.