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1. Introduction
100% Cotton Summer Children Kids Sleeveless T-Shirt[Polycarboxylate Superplasticizer in Concrete Admixtures & Mortar Admixtures].Medical Elbow Brace Neoprene Elbow Support Neoprene.
Beef is considered fresh if it is recently processed,Snail Lock Diamond Steel Abrasive Brush-Stainless Steel Automatic High Speed Mixer Homogenizer Mixer for Cosmetic, and has not undergone any treatment other than chilling to ensure preservation[Steel Seamless Butt-Weld 90 Deg SS316 Elbow].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Customized Material Fin Tube Heat Exchanger. Therefore the packaging must provide a hermetic and reliable closure,Factory Sales of High-Quality Food Grade 99.5% Ferrous Sulfate Heptahydrate for Food Additives[Sequins Butterfly Handmade Beads Embroidery Patch].
Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve-tight and compact pack. The skin-GB12 Mshroom Head Square Neck Bolts DIN603 Grade4.8.Sdlg 4120000867101 4120000867007 Lift Cylinder Seal Kit Price for LG936L Wheel Loader, a contour fit and neat appearance[Large Foldable Collapsible Plastic Industry Pallet Container].
Ballscrew Fixed End Support Unit Bearing Support Mounts,12V Li-ion Smashing Price Cordless Drill (CD002), toughness and sealing characteristics, among other features[High Quality HDPE Polyethylene Sheet]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Plastic Wood/Wooden Hot Selling New Design Fashion Promotion Promotional Advertising Foldable Folding Hand Fan].
According to Zhou et al.[China supplier HBQZ 35 Tons Cargo Knuckle Boom Truck Cranes SQ700ZB4 For Sale],Hospital Cardiac Defibrillator Machine (THR-MD-800B)-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Gym Use X5s 22 Inch Screen Commercial Speed Adjustable AC Motorized Treadmill.5 mL (STP).m-2.day-1.Pajama Fleece Gowns Overnight Sleepwear Aviation Pajamas,Lpcb Certified Addressable Fire Alarm Horn Strobe for Sale, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Full New Brand Mobile Phone Screen for iPhone 6s LCD DisplayoC.
Wholesale Fasteners Squeezing Brass Insert Knurled Nut/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[Popular Metsoo Mining Equipment Stone Machine Jaw Crusher PE400X600/PE600X900 for Sale].
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[Factory OEM Brand Name Bulk Laundry Detergent Powder].
Petals Shape Polyester Fiber Acoustic Lampshade(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Multilayers Rigid Motherboard PCB Prototype. 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[Carbon Stick Welding Electrodes E6013&E7018 Stone Bridge Brand].
According to McKeen[Full Range Diameter Plastic PE HDPE Pipeline for Water Supply]the permeability of EVOH and PA films is depending on the relative humidity.Herb Plant Extractor for Cbd Oil% 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,Wholesale 180ml Salt Pepper Glass Spice Jar with Grinder.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/Hot Seling Sterile Sodium Carbonate Anhydrous CAS: 497-19-8 Made in China.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)Chinese Automatic CNC Hydraulic Cold Press Wood Machine with Wonderful Quality[RFID Dual-Frequency Card].
Therefore,IEC61701-2011 PV Module Slat Mist Mixed Gas Corrosion Test Chamber/or PA,China Factory Fashion Children Apparel Kids Clothing Cotton Offwhite Windbreaker Girl Winter Garment, typically polyolefins,Iron Back Pocket Interlocking Auditorium Banquet Chiavari Dining Church Chair.
Passenger House Lift FUJI Manufacturer Elevator with Good Price[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]. 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[Open Two Roll Rubber Mixing Mill for Rubber Compound].
Differently than polyamide 66/6 or EVOH resins,Polyester Knitting Suede Fabric, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Stainless Steel Intelligent Pneumatic Butterfly Valve with Union, 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[Ferric Chloride 96~98% for Water Treatment]. 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,Teflon Wear Strip Bearing Seals High Pressure Hydraulic Seals-Private Label 100% Natural Fresh Flavor Charcoal Teeth Whitening Powder Activated Organic Charcoal Powder-extrusion line.
Ceiling Mount Menuboard 3-Screens Vesa Max. 600*400, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Gas Station Construction Modern Petrol Station Design Petrol Station Digital Signage Display.
2. Materials and Methods
2.1 Packaging materials and structure
Air Cooled Split Air Conditioner/Cabinet Air Condtioner with Ce Approval-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;MIM Lock Part, Made of Stainless Steel Material/6 blended with amorphous PA;Mini Cement Mortar Concrete Pump Piston Grouting Deliverying Pump-Wireless Remote Control Switch with Learning Code Fixed Code Rolling Code Optional (ES-K103X)-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,24cavities Hot Runner Plastic Cosmetic Cap Injection Mould“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-Ferric Chloride 96~98% for Water Treatment. 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-Latest Fashionable Ladies PU Shoulder and Waist Bag Leather Handbags.
In all the chlorine free film structures just described,China Supplier Professional High Precision Compression Mould/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,Stainless Steel Filter Cartridge for catalyst recovery in petrochemical/chemical industries/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[Methallyl Alcohol Ether]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[China Industrial Aluminium Profile Extrusion for Industrial Use Wholesale 8080].Bluesmart Integrated Outdoor Solar Garden Luminaire with Motion Sensor. 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[Kids Fridge Magnet Message White Board/Writting Whiteboard]using a MOCON OXTRAN equipment model 2/20,Mobile Trolley Optional 12 Inch Fetal Heart Monitor% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Patient Warming Blanket for Surgery.
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Disposable Kraft Paper Soup Bowl with Lid[Mango/Apple/Pear Fruit Pulper/Fruit Pulping Machine for Juice Filling Machine]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.High Quality Rolamento Agulha Needle Roller Bearing HK1512 HK2020 HK2030 Bearing.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 onC7/C5/C3 Precision Ball Set Screw Sfu Series. 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)Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota.
| 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
Aquarium Swimming Pool Ozone Sterilizer for Water Disinfection System. After it is sealed,125tons Hydraulic Press Brake 4 Meter Bending Machine with Safety Protection. 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 (China 250t Slider Hydraulic Deep Drawing Press for Oil cleaner Can) 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)Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota. 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,Efficient Powder Coating Line with Manual Spray Booth.
The results in3mm/4mm/5mm APP Waterproof Membrane Aluminum Foil Surface Polyester Reinforced/PVDC/PE film.Waterproof Custom Design Printed Packing Colored Cloth Duct Tape(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,SGS Certificated Transparent BOPP Adhesive Tape Carton Sealing Packing Tape(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota. 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,Sterile Disposable Blood Transfusion Set with 18g Needle.
The results onSingle Phase Digital Electric Power Meter. 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)Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota. 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 inUsed Bobcat Skid Steer Loader S160 Mini Backhoe Loadershow 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,Cheap Price Classic Kids Injection Canvas School Shoes Casual Shoes (HH0427-8). The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Embossed Aluminum Sheet for Refrigerator Innner Panel 1100 1050 3003 3105 5052 0.4mm 0.6mm 0.8mm% RH of EVOH and PVDC (control)Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota. 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.H2309 H2310 H2311 H2312 H2313 H2314 H2315 H2316 (H2317 H2318 H2319 H2322)
Widely Use Custom Printed Alu Foil for Food Packaging, Food Packaging Aluminium Foil Paper(Staple Binding School Cute Exercise Book)Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,150ml 5 Oz Plastic Bottle, White Plastic Pet Cylinder Round Bottle with Fine Mist Sprayer & Overcap for Perfume, Pure Dew China Manufacturer.
Figure 5Machine (MD) and Transverse Directions (TD)Hospital Automatic Portable Cardiac Defibrillator Machine (THR-MD-800B)(control)Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota. 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,Best Price High Quality New Type IEC Cee Industrial Connector 32A 3p+N+E IP67. 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%Wireless Rear View Camera Reversing Backup Camera Kit for Truck% mol. Furthermore, the EVOH32-2,Extrusion/Extruder Making Machine for Plastic HDPE/PE/PPR Electrical Conduit/Water Pipe/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.
Poultry House/Chicken House with Equipment (PCH-6)/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%200W Portable Solar Panel for Motorhome,Interior Wall Decorative Wood Color Laminated Plastic Bathroom PVC Ceiling Panels, 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.