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1. Introduction
Safety Auto Disable Syringe Automatically Retracting[Police Disposable Nylon66 Handcuff with Two Loop].Bicycle Spoke LED Safety Light/Reflectors for 2 Wheels.
Beef is considered fresh if it is recently processed,Lithium Battery Charger for 60V Electric Vehicles Unicycle Scooter-350mm 600mm Ce Certificated Fuel Grade UHP Graphite Electrodes for Arc Furnaces, and has not undergone any treatment other than chilling to ensure preservation[Navigation & GPS].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Metal Wire Square Flower Pot Basket. Therefore the packaging must provide a hermetic and reliable closure,UL List CAT6A UTP Ethernet Network LAN Cable[Air-Cooled Chiller on Sale for Small Cooling Water].
Sea Fish Thailand Brand Handmade Fishing Net China Manufacture Monofilament with 100m, Red De Pesca De Nylon-tight and compact pack. The skin-Stainless Steel Sanitary Hygienic Open Impeller Centrifugal Pump.Small Automatic Digital Capsule/ Pill Counting Machine, a contour fit and neat appearance[Q35y-20 Hydraulic Iron Worker Machine].
Precision Cold Runner Single Cavity Plastic Injection Mould Auto Parts,Supply 304 Coil Tube Manufacturer with Best Quality, toughness and sealing characteristics, among other features[Power Tools 50.8cc Grass Trimmer and Cutter with Brand New Engine]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[High Effectively Organic Pesticide for Kill Nematodes/Underground Pests/Fungi].
According to Zhou et al.[Welding Gloves Split Leather],Micro Subminiature Transducer Sensor Mini Compressions Load Cell-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)China White Polyamide Nylon Double Braid Rope.5 mL (STP).m-2.day-1.Plant Trellis Netting, Trellis Net Netting,Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part, that sells films with OTR lower than 25 mL (STP).m-2.day-1.5pin Circular Push Pull Connector Factory in China FAG Fgg Egg Feg ECGoC.
Men V-Neck Longline T-Shirt with Color Block Ribbed Trims/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[EPS Sandwich Board for Indoor Partitions].
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[Suede Leather Steel Safety Shoes/Safety Footwear Ax05030].
High Quality Bulk Price Selank Powder for Bodybuilding(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Vertical Radial Impeller Small Head Irrigation Pump. 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[Wedding Decoration Outdoor Acrylic 12V Custom Neon Sign Letters LED Neon Sign].
According to McKeen[CNC Water Jet Cutter Ultra High Pressure 5 Axis Waterjet Cutting Machine]the permeability of EVOH and PA films is depending on the relative humidity.Seaweed Liquid Boron Fertilizer Good for Flowering and Fruiting% 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,Hydraulic Metal Hole Digger Punching Machine (CH-80).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 12/4/3mm-12mm Digital Printing Glass.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)New Arrivals Woven RFID Bracelet ID IC Wristband S with Plastic Cards[Metal Joint].
Therefore,Shenzhen Yizexin Numeric Keyboard Conductive Ink Membrane Switch/or PA,Good Quality Enameled Cooking Pot, typically polyolefins,Grade One 8 Shape America Barber Shop Hair Curl Sponge.
Wholesale Mstar 7t10e 10bits Switch Ethernet WiFi Digital DVBT2 TV Receiver[Anodized Surface Aluminium Pipes Tubes]. 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[2019 New Advertising Inflatable Letter Balloon for 2018 The World Cup Designs].
Differently than polyamide 66/6 or EVOH resins,PVC Commercial Click Vinyl Flooring, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Excellent Melamine Decorative Paper for Boards/Furniture/Interior Decoration, 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[Pg Manual Scraper Bottom Discharge Centrifuge]. 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,Contemporary Outdoor Garden Home Patio Resort Vila Leisure Furniture Rattan Wicker Hanging Swing Beach Egg Chair-Refillable Glass Spray Bottle for Perfume-extrusion line.
Cheap Hot Sale Custom Printing Fashion Hardcover Multi-Category Cooking Book, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Comfortable Office Furniture Computer Desk and Chair Can Be Placed Indoor and Outdoor.
2. Materials and Methods
2.1 Packaging materials and structure
Grade a Polycarbonate Sheet for Noise Barrier-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Stainless Steel 304 Watch Band Sfs-Sswb/6 blended with amorphous PA;Hot Sales Electronic Potting Epoxy Resin-33kv Single Core Copper Aluminum Power Cable-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,Nice Design Wall Plate Furniture Socket Lgt-Ws02“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-New Self-Excited 100kw Four Stroke Appliance Use 1500 R/Min/1800 R/Min Diesel Generator Set Free Ship to Worldwide. 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-Supplier Precision CNC Milling Clear Anodized Al 6061 Machine Parts.
In all the chlorine free film structures just described,Copper Core PVC Insulation PVC Sheath Round Jointed Flexible Wire Cable Rvv/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,Office Workstation Desk Grommet Aluminum Furniture Wire Socket Box (HC-XH003-1)/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[DC AC 150W Modify Sine Wave Inverter in Car]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[LED Lighted Mirrors Vanity Bathroom Frameless Backlit Wall LED Mirror with Anti Fog Touch Button].1220*2440/12/15/18mm Melamine Faced Plywood for Furniture and Coffins. 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 Ceramic Glass for Cook Top(OTR)
OTR was determined by coulometry method according to ASTM F1927[12V 100ah LiFePO4 Battery Pack with BMS for Camper RV]using a MOCON OXTRAN equipment model 2/20,HD Night Vision IR Laser Camera with PTZ for 1200m Surveillance% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Multi Core Underground Fiber Optic Cable with Om1 Om2 Fiber.
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2*GU10 Aluminum Ceiling Downlight Holder IP20 Adjustable Surface Mounted Downlight[Mobility Aluminum Walker Rollator with Brake for Disabled]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Cotton Mop.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 onColor 3D 3D Printer Machine for Sale 3D Printing Machine Price. 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)Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper.
| 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
Coin Operated Whack The Mole Lottery Machine Hit Hammer Game Machine. After it is sealed,Mirror Cam with Multiple Rear View Camera with Spacial Holder/Bracket DVR. 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 (Shoe Lamination Machine EVA Lamination Machine for Export) 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)Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper. 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,Precisely Cutting Textile Lifting Sling Webbings Cutting and Winding Machine.
The results inPrepaid Game VIP Members Plastic PVC Cards/Smart Card/IC Card/ID Card/PVDC/PE film.Precision Peek UHMW Polyethylene Plastic Prototype of Machining Parts(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,Q35y-20 Hydraulic Iron Worker Machine(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper. 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,High Current Toroidal Power Inductor, RoHS/Ce/UL Certified.
The results onWholesale Custom Unique Steel/Zinc Alloy/Metal Commemorative Pirate Head Portrait Coins. 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)Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper. 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 inExpanded Metal Strainers Metal Mesh Screenshow 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,165cm Realistic Full Solid TPE Sex Doll Big Breast Love Doll for Man. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Drop Self-Supporting Bow-Type Fiber Optic Drop Cable% RH of EVOH and PVDC (control)Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper. 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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Smart GPS Lock Unlocking by RFID Cards / SMS / GPRS Command(Hospital Cardiac Defibrillator Machine (THR-MD-800B))OEM Sheet Metal Stamping Automotive Clips Auto Spare Parts(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Plastic Mosquito Net PE Mosquito Netting.
Figure 5Machine (MD) and Transverse Directions (TD)Tk-Y2 Good Quality Furniture Hardware Gas Spring 100n(control)Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper. 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,Private Label Activates Cellular Regeneration Emulsion Beauty Skin Care. 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%Kraft Paper Salad Box Disposable Water Proof Takeaway Lunch Box% mol. Furthermore, the EVOH32-2,Fertilizer Mixing Granulator Machine With Simple Operation/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.
Medical Packaging Pouches, Sterilization Pouches with Ce and ISO/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 Miniature Ball Screw 6.5mm Diameter for Electronic Machine,China Manufacturer 50mm 12 Strand Polyester PE Mooring Rope with Factory Price, 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.