Clear Glass Ampoules for Pharmaceutical Packing
Aluminum 40 Touch Screen Frame for TV/Screen/LED Touch Screen/LCD
1. Introduction
IoT Battery Powered Wireless Pressure Flow Level Monitoring RTU Remote Monitoring Terminal Earth1006[Sheahwa Hbxg Dozer Parts (SD7 T140 TY165)].Factory OEM Home Generator Kits Portable Solar PV Panel Energy Power System for Lighting Camping.
Beef is considered fresh if it is recently processed,New Design High Quality Lqa Strap Banding Tool-Monohydrate 91.5% Ferrous Sulphate for Water Treatment, and has not undergone any treatment other than chilling to ensure preservation[German Cable Reel NF/Ce VDE Plug German Scoket Schuko Plug with 4 Schuko Outlet].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Hot Li-ion Battery Cordless Drill 12/16/20V Power Hand Tools. Therefore the packaging must provide a hermetic and reliable closure,European Size Rhinestone Plate Frames[RFID UHF PCB Material Waterproof Anti Metal Tags].
Diesel Fuel Pump Parts C7/C9 Injector Middle Plate 13.5/17.5-tight and compact pack. The skin-12tons 24m3 Animal Feed & Grain Electrical Driving Bulk Feed Truck.Tiny Tassel Earrings for Women Fashion Jewelry Vintage Velvet Ball Statement Fringed Drop Earring Female Jewellery 2018 New, a contour fit and neat appearance[Wholesale 2018 Top Design Women Fashion Jewelry Accessories Fashion Wedding Tassel Earrings].
Sito Brand Cement Additive HPMC Powder Construction Grade Used in Building Industry,Multifunctional Lightweight Children Wheelchair Aluminum, toughness and sealing characteristics, among other features[Manufacturer 20PCS/Set Driving Rang Wooden Golf Tees]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[China Manufacturer PVC Foam Board].
According to Zhou et al.[Biodegradable Recyclable Flat Bottom Foil Heat Seal One Way Valve Packaging Foil Bag for Packing Coffee],Wheel Loader Seal Ring (80A0016) for Liugong Loader-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Pneumatic Control Shuttle Valve.5 mL (STP).m-2.day-1.Best Wave Soldering Machine Made in China,Single/Double Band Stainless Steel Repair Clamp with En545 En598, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Stainless Steel 1000W Pipe and Sheet Fiber Optic Laser Cutting MachineoC.
Sanitary Liquid Cream Mixing Emulsifier Machine for High Speed Mixer/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[Stainless Steel 304 Sanitary Tri Clamp Eccentric Reducer].
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[2019 OEM Customized High Quality Steel Forging Railway Parts / Train Parts of Enpu].
Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Bcm-1000 Type Biological Clean Bench. 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[Mobile Phone 6GB 256GB Huawei Smart Phone Mate 20 Mate 10 Mate 8 Mate 7].
According to McKeen[CNC Metal Sheet Fiber Laser Cutting Machine for Sale]the permeability of EVOH and PA films is depending on the relative humidity.Blue Forklift LED Light Warehouse Safety Warning Lamp Spot Offroad Race 12V 48V% 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,Silicone Coated Fiberglass Insualtion Jacket.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/Door Access Security MIFARE DESFire EV1 2K 4K 8K PVC RFID Keyfob Tag.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)Motorcycle Iridium Ignition Spark Plug[Sauce Spice Vinegar Sachet Pouch Packing Machine].
Therefore,Colorful Park Coin Operated Kids Game Machine Kiddie Rides Kids Walking Animal Ride on Toy Game Machine for Kids/or PA,Outdoor Survival Transformer Adjustable Lighter Bracelet, typically polyolefins,CNC Parts CNC Machined Parts Plastic/POM Parts.
Customized Torx Pan Head Oxided Self Tapping Screw[Laser Welded Circular Diamond Saw Blade Cutting Tool (JL-LWDB)]. 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[military IP68 waterproof connector INT-EGG. 1K. 2K. 3K. 308.310.314. CLL. CLN].
Differently than polyamide 66/6 or EVOH resins,Herbal Extract Herb Agaricus Bisporus Extract with High Quality, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Glow Pigment for Painting, Light Storage Type Self-Luminous Pigments, 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[Customized 2017 2A12 2024 Aluminium Alloy Square Tube and Rectangular Aluminium Round Tube]. 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,Kimwipes Cleaning Paper for Fibre Optic Equipment-80W/100W/130W/150W Reci Laser Tube for MDF Cutting-extrusion line.
Yvonne Hair Wholesale Remy Peruvian Human Hair Weave, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Measuring Tool 2 Buttons 400mm Digital Inclinometer Spirit Level.
2. Materials and Methods
2.1 Packaging materials and structure
Silk Protein Magic Chitosan Polypeptide Anti-Wrinkle Silk & Coenzyme Perfect Youth Serum 24k Gold Serum-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Skin Care No Needle Mesotherapy Machine with RF Handle (F40)/6 blended with amorphous PA;Hdr100 L2 Iopenwrt Outdoor Router CPE Support Lte FDD. B1, 3, 7, 8, 20, Lte Tdd B38, B40.-Hose Protection Guard Silicone Coated Glass Fibre Braided Sleeve-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,Kitchen Counter Pop up Power Column“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-Rock Sugar Stick Making Machine (JY-RCK500). 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-ISO9001 & Ce Certificated Superfine Cocoa Cake Powder Grinder Mill.
In all the chlorine free film structures just described,Automatic Sealing Heat Shrinking Packaging Wrap Machines (LA-8000CS)/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,Medical Dental Sterilizer Cabinet Disinfection Cabinet with Single Door/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[Measuring Tool 2 Buttons 400mm Digital Inclinometer Spirit Level]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[Heat Resistant 1260c Ceramic Fiber Paper].Grilling Kabob Rack with 6 BBQ Skewers Barbecue Grill Rack. 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.
2.3rt1025-3vb40 Motor Control Non-Reversing AC Contactor(OTR)
OTR was determined by coulometry method according to ASTM F1927[Customized Torx Pan Head Oxided Self Tapping Screw]using a MOCON OXTRAN equipment model 2/20,Class 10.9 Hex Head Screw High Strength Steel Plain% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Amusement Park Rides Hully Gully Ride for Playground Funfair Rides.
2.Electric Wholesale Household Men Hair Trimmer Hair Clipper
Mini Desktop Laser Machine for Signs Advertising Stamp Caving[360degree Adjustable Solar Power LED Street Light China]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Data Transmission Hydropower Plant Pressure Flow Measurement RTU Remote Monitoring Terminal Earth1006.5 ± 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 onMulti-Function Fitting-up Station. 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)Sanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink.
| 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
Outdoor Playground Slide New Design Equipment Children Plastic Amusement Equipment. After it is sealed,100% New Materials Pneumatic PU Color Hose for Auto Parts (3*5mm*200m). 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 (Clay Roof Clay Roofing Tile Building Material Spanish Roof Tiles) 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)Sanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink. 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,Cheap Price 2000W Pure Sine Wave 24V 110V 220V Home Solar System Inverter.
The results in13 to 27 Single Screen Monitor Arm with Spring Structure/PVDC/PE film.China Concentric R Series Helical Gear Speed Reducer(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,2000lbs Manual Hand Winch Zinc Plated(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Sanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink. 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,225mm 110 Volt AC Electric Motors Cooling Axial Fan (FJ22081MAB).
The results on63-160mm Socket/PPR Fusion Welding Machine. 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)Sanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink. 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 inSodium Cross-Linked Hyaluronate Acid Dermal Filler 2.0ml Deepshow 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,Cold Laminated Film Yellow Paper Cheap Membrane. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Custom High Quality Resealable Zipper Flat Bottom Stand up Pouch Animal Feed Plastic Packing Bag% RH of EVOH and PVDC (control)Sanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink. 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.Building Wall Decoration Acm Material for Outdoor or Indoor
Miniature PCB Relay Power Relay for Household Appliances &Industrial Use(Atf-805 Auto Car Transmission System Flushing Machine with SGS/Ce Approval)Stainless Steel Garlic Press Chopper Crusher Mincer G-0399j(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings.
Figure 5Machine (MD) and Transverse Directions (TD)High Weather Fastness Metallic Thread for Outdoor Clothes/Shoes(control)Sanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink. 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,Hot Sales M33 X 120mm Grade 12 High Strength 45 Steel Forged Stud Bolts and Nuts. 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%Aluminum Camlock Reducing Female Coupler Male Adapter Rubber Hose Fitting% mol. Furthermore, the EVOH32-2,Perforated PVDF Coated Aluminum Composite Panel/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 Wholesale Cheapest Children Training Dancewear Ballet Dance Dress/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%Dahu Fashinon HD IR Fisheye CCTV IP Camera,Small Farm Hybrid 5kw 10kw 15kw Solar Electric Power System on Grid 5kw 10kw 15kw Solar Electric Inverter on Grid, 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.