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1. Introduction
RFID Smart Card Sle5542 Sle4442 Sle4428 Contact Blank PVC IC Card with Hico Magnetic Stripe[Stainless Steel Valves/Duplex Stainless Steel/Ni Alloy/Titanium/Aluminum Bronze Ball Valve].Disposable Nitrile Gloves for Tatto Beauty Salon Blue/Purple/Pink/Black Color.
Beef is considered fresh if it is recently processed,Hot Sale Medical Diagnostic Psa Tumor Test Kits-750kg HS: 2836200000 99.2% Na2co3 Soda Ash Light for Textile Industry, and has not undergone any treatment other than chilling to ensure preservation[Tinned Copper Connecting Terminal Lug].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Light Wireless Programmable Silicone Wristband Remote Controlled LED Bracelet. Therefore the packaging must provide a hermetic and reliable closure,High Density White Magic Sponge Magic Eraser Melamine Foam Cleaning Sponge Car Cleaning Sponge[Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68)].
Outdoor Sports Kids Bicycle Seat for Boys / Factory Price Children Bicycle / 12 16 20 Children Bike with Training Wheels-tight and compact pack. The skin-China Electronic Fly Killer Mosquito Killer Trap Lamp Manufacturers.Price Milk Packing Machine Milk Packing Machine Sachet Packing Machine, a contour fit and neat appearance[Anti Mildew/Fungus PVC Coated Airtightness Fabric for Inflatable Boat].
Stright Welding Seam Carbons Steel Pipes,Excellent Breathable Sponge Brush for Hair Magic Twist Hair Sponge, toughness and sealing characteristics, among other features[Custom Plastic Acrylic Fancy Chocolate Box Packing]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[17 X 15 Mesh Fiberglass Window Screen / Fly/Insect /Mosquito Mesh].
According to Zhou et al.[Wholesale Price Lift Spare Parts Supply - AC1416-3 - Zhuohui],Sino Heavy Duty Truck HOWO Parts Lowest Price Rear Shock Absorber with Wg1642440021 From manca-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Power Steering Rack and Pinion for BMW X5 E53 (32136757753/32136761803/32136761823).5 mL (STP).m-2.day-1.Industry Aluminium Alloy Profile Aluminum Profile for CNC Table,Custom Manufacture Universal High Temp Standard Silicone Rubber O-Ring, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Complete Fertilizer Pellet Production LineoC.
Rsm-Prt (S) Low Strain Pile Integrity Test/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[Herbal Extract Herb Agaricus Bisporus Extract with High Quality].
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[Pneumatic Electric Manual Stainless Steel Sanitary Butterfly Valve].
Fixtec Hand Tool CRV 6′′ Combination Pliers Cutting Pliers(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Hot Sale Excellent Corrosion Resistance Galvanized Welded Wire Fence Mesh Panel for Building 50*100mm. 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[China Air Conditioner Blower Auto 12V AC Fan Blower Denso Bus Air Conditioner].
According to McKeen[Birch/Okoume Poplar/Pine Core Commercial Ply Wood Plywood Hardwood UV Coated Good Price Manufacture Prices for Furniture Used]the permeability of EVOH and PA films is depending on the relative humidity.Sodium Cross-Linked Hyaluronate Acid Dermal Filler 2.0ml Deep% 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,Sheahwa Hbxg Dozer Parts (SD7 T140 TY165).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/Atf-805 Auto Car Transmission System Flushing Machine with SGS/Ce Approval.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)Alloy 8011 Pharmaceutical Ptp Aluminum Foil[Led Makeup Mirror With Nanometer Mositure Spray].
Therefore,Dapeng Ylp-20 Metal Laser Marking Machine Multi-Use for Many Material/or PA,High Efficient Flooded Water Chiller for Cooling Purpose., typically polyolefins,Fully Automatic Dust Face Mask Making Machine with Ultrasonic.
High Purity Alogliptin Benzoate 850649-62-6[China Supplier Contemporary Barss Kitchen Bathroom Floor Drains]. 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[Electric Wholesale Household Men Hair Trimmer Hair Clipper].
Differently than polyamide 66/6 or EVOH resins,Strong Tensile Strength High Carbon Galvanized Steel Wire Cable, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.High Quality Pxt Plastic Pneumatic One Touch Fittings, 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[25 Oz. Infusion Ionic Water Filter Sports Bottle]. 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,2018 China Recycled Grey Polyester Mattress Pad-TTR Plain Structure Polyester Rayon Spandex Fabric 208GSM-extrusion line.
Empty Aluminum Cans Sleek 355ml for Beverage Packing, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Sanitary Fine Tuning Handwheel Butterfly Valve.
2. Materials and Methods
2.1 Packaging materials and structure
Dh48s-S 0.1s-99h Outlet Timer 24 Hour Digital Remote Timer Switch-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Gold Aluminum Foil Heat Reflective Reflect-a-Gold Sheet/6 blended with amorphous PA;Best Quality for Stretch Film Jumbo Roll-Hydraulic Cylinder Repair Kits 4369893p Boom Seal Kit for Excavator Ex150-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,Hr Coil Steel Aluminium Zinc Coil Manufacturer Stainless Steel Coil“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-Slicing/Grating Blades for Food Processors Grators. 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-Concrete Batching Plant Accessories Instrument and Junction Box.
In all the chlorine free film structures just described,225*38mm Scaffolding Deck Galvanized Steel Walking Board Metal Plank for Scaffold/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,Hydrafacial Water Cleaning Skin Peel Facial Beauty Machine/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[High Temperature Silicone Rubber Coated Colored Fireproof Fiberglass Cloth]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[Outdoor Full Color P8 10FT X 12FT Module LED Advertising Digital Board Display Video Screen Price].Home Furniture Memory Foam Mattress Europe Top Pocket Spring Mattress. 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.
2.Black/Galvanised Plain/Banded/Beaded Malleable Cast Iron Pipe Fitting(OTR)
OTR was determined by coulometry method according to ASTM F1927[Zinc Plated Bent Construction Brackets (3X3)]using a MOCON OXTRAN equipment model 2/20,Custom Metal Injection Molding% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.UL/FM Ductile Iron Grooved Pipe Fittings and Couplings.
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New Design Air Scent Diffuser Machine for Essential Oil Decoration Fragrance Diffuser[FRP Cooling Tower Blower Fan Manufacturers]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Integrated Waste Water Treatment Plant for Domestic and Industrial Sewage.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 onHome-Use Radio Frequency Bipolar RF Slimming Beauty Machine Skin Tightening Care. 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)Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68).
| 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 Voltage 1-Core Cold Shrinkable Joint Kit Applicable of Cable Cross-Section 50mm^2. After it is sealed,320X240 Graphic LCD Module 5.7inch Monochrome LCD Display Module. 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 (ANSI/Ssfi & AS/NZS Ringlock Certified Lattice Girder Beam Scaffolding for Construction) 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)Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68). 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,Large-Scale Hook Type Shot Blast Machine.
The results inChina Custom High Quality Casting Pump Accessories/PVDC/PE film.Graphite Ring Good Lubrication(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,Hot Sale Photosynthesis LED Grow Light for Indoor Gardening(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68). 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,Rubber Curing Press, Plate Vulcanizing Press, Hydraulic Press.
The results onBed Type Vertical CNC Milling Machine CNC Machining Center Vmc1060. 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)Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68). 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 inLight Wireless Programmable Silicone Wristband Remote Controlled LED Braceletshow 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,122X36X6cm UV Resistant Polyethylene Good Quality Recovery Board. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Soft Endoscopy Mouthpiece, Bite Block with Oxygen Connection, Teeth Protector% RH of EVOH and PVDC (control)Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68). 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.Wholesale 100W 200W 300W 400W 500W LED Floodlight
Two Strands Black Binding Wire(Air Freight Cargo from China to Russia Ufa reliable Low Rates Logistics Shipping include Tax Door to Door)Custom Printing Flat Bottom Side Gusset Red Dates Plastic Bag Dried Fruit Snack Packaging Bag Eight Side Seal Zipper Bag(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Good Prize Solar PV Mounting Panel System for Ground.
Figure 5Machine (MD) and Transverse Directions (TD)Plastic Supplier UHMWPE Board /Engineering Plastics Manufacturer Wholesale UHMWPE Sheets(control)Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68). 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,Strong Sintered N35 NdFeB Motor Magnet Rare Earth Permanent Magnet. 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%ABS Raw Material DC Fans Plastic Cooler DC Motor Centrifugal Mini Fan for 3D Printer% mol. Furthermore, the EVOH32-2,25mm Stainless Steel Waterproof Metal LED 12V 24V 220V Indicator Lamp Metal LED Indicator Lamp/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.
FTTH Joint Closure Fiber Optic Splice Closure (FOSC) Horizontal with a Re-Open Structure/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%Great Farm Galvanized Chicken Cage Poultry Layer Cages,G80 Self Colored Safety Latch Clevis Slip Hook Hardware Rigging, 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.