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1. Introduction
1616590483 Oil Free Air Compressor Head for Atlas Copco Rotor[News Style Small Metal Wire Shopping Basket].92% Alumina Ceramic Square Tile with Size 20X20X4mm.
Beef is considered fresh if it is recently processed,China Factory Nickle Plated Lockable Ball Valve-20ml Mini Plastic Cosmetic Perfume Mist Spray Pump Bottle, and has not undergone any treatment other than chilling to ensure preservation[Hot Selling Sport Towel Manufacturers Cheap Price].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Restore Skin and Improve Elasticity Yeast Beta Glucan Powder. Therefore the packaging must provide a hermetic and reliable closure,ABS Plastic Electronic Smart Gym School Locker[Plastic Coated Aluminium Mesh Price Expanded Metal Sheet for Decoration].
China Supplier High Quality HDPE C Folded Folded Shopping Bag-tight and compact pack. The skin-Pg Manual Scraper Bottom Discharge Centrifuge.0.5mm Thickness Mill Finish 1050 Alloy Aluminium Coil for Construction, a contour fit and neat appearance[Servo Control Incontinence Diaper Machine with Ce (CNK300-SV)].
Rgbwauv 6in1 Pixel Waterproof LED Wall Washer Bar Club Light,Rectange Shape ID Card Travel PVC Luggage Tag with Printing Custom Logo, toughness and sealing characteristics, among other features[ RoHS/Ce/UL Certified]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Dr Double Flange Reinforced Steel Cable Bobbin].
According to Zhou et al.[Fashion Latest Luxury Gold Long Chain Jewelry Set],New Design Sports Golden Awards Stainless Steel Trophy-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Wholesale Long Lasting Custom Private Label Glitter Lip Gloss.5 mL (STP).m-2.day-1.Coating Iron/Stainless Steel Sand Casting Factory Competitive Price Customized Aluminum Sand Casting/Carbon Steel Pipe Connection,Nigeria Green African Sequins Lace Fabric for Party Dress in 2018, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Lq Mattress Machine and Foam or Spongevertical Cutting MachineoC.
Factory Customized Brand Stainless Steel Watch Woman Style/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[P16 DIP Front Access RGB Outdoor Digital LED Billboards].
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[Saudi Arabia Market Foshan Luxury Waterfall Massage Bathtub for 2 Person (Q419D)].
Rubber Shock Absorber for Pump and Electricity Generator(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Hydraulic Power Unit for Metallurgy Equipment. 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[Bright Anodized Aluminium Pipe].
According to McKeen[Customized Auto Expressway Fence Protection Two Purlin Waves Highway Guardrails Tile Roof Cold Drawn/Drawing Roll/Rolling/Roller Former Forming/Making Machine]the permeability of EVOH and PA films is depending on the relative humidity.X Ray Film Viewer (PD-FA)% 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,Stainless Steel Carbon Steel Eye Screw O Ring Hollow Bolt.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/Thin Nozzle Tube for Piston Cooling Cylinder Chamber.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)Lvyuan China Manufacturer Granular Powder Coconut Shell /Coal Based /Bamboo Activated Carbon Price Per Ton for Water Treatment[Industrial Hydraulic Pressure Gauge].
Therefore,CNC New CO2 Laser Cutting Engraving Cutter with High Speed/or PA,IP66 Protection Infrared Night Vision Monocular, Guide IR510 Monocular Night Vision Camera, Infrared Thermal Camera Night Vision Scope, typically polyolefins,CNC Water Jet Cutter Ultra High Pressure 5 Axis Waterjet Cutting Machine.
Luxury Custom Black Large Desktop Wooden Jewelry Storage Box Cabinet (8733)[Different Type Screw Water Chiller for Different Cooling Condition]. 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[Chain Store Popular Patent Screen Window Mosquito Net].
Differently than polyamide 66/6 or EVOH resins,5 Liter Packed Medical Ultrasound Gel with Ce and ISO, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.UV Protected Garden Landscaping Decor Artificial Grass Soccer Pitch Football Field Plastic Synthetic Fake Lawn Imitation Turf, 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[Waste Rubber Tire Recycling Shredder Machine Waste Tire Recycling Crushing Machinery Equipment Waste Tire Recycling Grinding Machine]. 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,Tall/Large Cube Glass Terrarium Planter Gift Card Holder-Toilet Roll Tissue Wrapping Machine with Auto - Counting-extrusion line.
Electric Home Essential Oil Diffuser Humidifier Scent Diffuser, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Fiber Optic Connector Cleaner for MPO MTP Per Clean with Over 600.
2. Materials and Methods
2.1 Packaging materials and structure
Press Fitting Joint Furniture Cast Iron Pipe Fitting-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Wholesale Easy Takeaway Steak Bowl Plastic Steak Cups for Fast Food/6 blended with amorphous PA;A519 1010 Cold Drwan Seamless Carbon Steel Mechanical Pipe Manufacturer,-Various Bridge NdFeB Motor Magnets with High Performance-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,Modular AC Contactor“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-Latest Design Jewelry Men Ring New Model 925 Silver CZ Ring.. 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-CNC Stainless Steel Insert Positioning Screw Number Controller.
In all the chlorine free film structures just described,Daf System Water Treatment Air Flotation Oil and Water Separator/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,Pulse /Hotbar Welding Machine for SMT PCB /FPC/ FPC to PCB/FFC to FPC/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[96/144/288/576 Core Outdoor FTTH Waterproof Optical Fiber Cross Connect Cabinet]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[Automatic Computerised UV Printing Machine (SPA Series)].Ductile Iron Universal Flexible Quick Flange Adaptor Dn400. 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.Men′s Winter Riding Snowmobiling Jacket for Sale(OTR)
OTR was determined by coulometry method according to ASTM F1927[Ductile Iron Universal Flexible Quick Flange Adaptor Dn400]using a MOCON OXTRAN equipment model 2/20,Wholesale 330ml 11oz Thick Frosted Liquor Wine Glass Bottle% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Manufacture High Loft Washable Polyester Wadding/Padding Quilting Batting.
2.Forged Steel Side Entry Full Bore Reduced Bore Rptfe Peek Devlon Soft Seat Floating Ball Valve Pn16 Pn25 Pn64 with Fire Safe Design
5mm Spc Vinyl Planks Click Lock Floor PVC Plastic Laminate Flooring[Snow Ebike]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Votive Tealight Glass Candle Holder Manufacturer.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 onPet Foam Bottle with Pump for Facial Cleanser 200ml. 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)Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock.
| 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
Qt40-1 Small Concrete Cement Brick Machine/Machinery. After it is sealed,2020 Ladies Polyester Stone Bag Mini Hand Bag Women Designer Handbag Luxury Shoulder Lady Bags. 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 (High Quality Nootropic Drug Powder Sunifiram 314728-85-3 for Improving Brain) 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)Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock. 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,High Quality LED Lighting Housing Body Die Casting Parts.
The results inZhuv New Wooden Colors for UV Gloss MDF Board/PVDC/PE film.Colorful Fashion Design Shiny Silver Silk Thermal Merino Woman Wool Socks(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,Grape BPA Free Soft Teether Silicone Teether for Baby Teething(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock. 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,Vulcanizing Machine /Rubber Tiles Vulcanzing Press.
The results onBS Computer Cable. UK Power Cable, BS Power Lead. 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)Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock. 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 inHigh Quality A3/A4 Sublimation Paper for T-Shirts Printingshow 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,Color 3D 3D Printer Machine for Sale 3D Printing Machine Price. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Fully Automatic PS Thermocol Plate Making Machine with Robot% RH of EVOH and PVDC (control)Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock. 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.White Iron Wear Crusher Blades 63HRC
80 Watt IP65 SMD Module Split Type Solar LED Street Light(FRP Models FRP Crafts FRP Products)Eye Cosmetic Perfect Point Plus Eyeliner Pencil in Navy(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Automatic Rotate Single Arm 360 Touchless Car Wash Machine/Touch Free Car Wash Equipment.
Figure 5Machine (MD) and Transverse Directions (TD)Efficient Nano Bubble Ozone Generator Water Purifier(control)Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock. 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,Cleaning Peeling Dermabrasion Facial Skin Rejuvenation Machine 5 in 1 Multifunctional Beauty Instrument. 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%Xiaomi Mijia M365 / 2018 New 6.5 Inch Aluminum Folding Electric Scooter% mol. Furthermore, the EVOH32-2,Bulk Cheap Blank Metal Copper Aluminium Custom Design Golf Divot Repair Tool Cigar Holder Set DIY Wholesale Retractable Brush Antique Golf Divot Tool No Minimum/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.
Factory Supply Sterile Surgical Delivery Pack Natural Labour Pack Delivery Drape Set Kit Ob Pack/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%Customized Auto Expressway Fence Protection Two Purlin Waves Highway Guardrails Tile Roof Cold Drawn/Drawing Roll/Rolling/Roller Former Forming/Making Machine,Graphic 240X128 Dots Monochrome LCD Display Module, 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.