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1. Introduction
Thin Nozzle Tube for Piston Cooling Cylinder Chamber[Calculator Silicone Membrane Keypad Lenses with Connectors].Lvyuan China Manufacturer Granular Powder Coconut Shell /Coal Based /Bamboo Activated Carbon Price Per Ton for Water Treatment.
Beef is considered fresh if it is recently processed,CNC New CO2 Laser Cutting Engraving Cutter with High Speed-IP66 Protection Infrared Night Vision Monocular, Guide IR510 Monocular Night Vision Camera, Infrared Thermal Camera Night Vision Scope, and has not undergone any treatment other than chilling to ensure preservation[Effective Sprinkler Cart].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,CNC Water Jet Cutter Ultra High Pressure 5 Axis Waterjet Cutting Machine. Therefore the packaging must provide a hermetic and reliable closure,Luxury Custom Black Large Desktop Wooden Jewelry Storage Box Cabinet (8733)[Wholesale Easy Takeaway Steak Bowl Plastic Steak Cups for Fast Food].
5 Liter Packed Medical Ultrasound Gel with Ce and ISO-tight and compact pack. The skin-UV Protected Garden Landscaping Decor Artificial Grass Soccer Pitch Football Field Plastic Synthetic Fake Lawn Imitation Turf.Tall/Large Cube Glass Terrarium Planter Gift Card Holder, a contour fit and neat appearance[China Manufacturer Direct Sell UV Birch Plywood Price for Die Making].
Toilet Roll Tissue Wrapping Machine with Auto - Counting,Electric Home Essential Oil Diffuser Humidifier Scent Diffuser, toughness and sealing characteristics, among other features[Far-11kv 800A 12.5ka Hv Vacuum Circuit Breaker with Controller /CT/ Zct/ Disconnector]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Facial Skin Care Soft Puff Face Washing Natural Konjac Sponge].
According to Zhou et al.[M7 Screw/Special Screw/Self Drilling Screw/No 5 Point Screw],Fiber Optic Connector Cleaner for MPO MTP Per Clean with Over 600-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Press Fitting Joint Furniture Cast Iron Pipe Fitting.5 mL (STP).m-2.day-1.Wholesale Easy Takeaway Steak Bowl Plastic Steak Cups for Fast Food,A519 1010 Cold Drwan Seamless Carbon Steel Mechanical Pipe Manufacturer,, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Various Bridge NdFeB Motor Magnets with High PerformanceoC.
Modular AC Contactor/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[Washami Manufacturer OEM Brands Teeth Whitening Charcoal Toothpaste].
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[Ultrasonic Humidifiers Mist Maker Air Humidifier Mini USB].
Latest Design Jewelry Men Ring New Model 925 Silver CZ Ring.(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)CNC Stainless Steel Insert Positioning Screw Number Controller. 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[Custom Insulated Polar Fleece Football Scarf /Gloves /Beanie /Cap].
According to McKeen[ Steel Gasoline Chainsaw Price]the permeability of EVOH and PA films is depending on the relative humidity.Daf System Water Treatment Air Flotation Oil and Water Separator% 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,Pulse /Hotbar Welding Machine for SMT PCB /FPC/ FPC to PCB/FFC to FPC.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/Ductile Iron Universal Flexible Quick Flange Adaptor Dn400.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)Men′s Winter Riding Snowmobiling Jacket for Sale[12.7mm Pc Strand Wire].
Therefore,Wholesale 330ml 11oz Thick Frosted Liquor Wine Glass Bottle/or PA,Manufacture High Loft Washable Polyester Wadding/Padding Quilting Batting, typically polyolefins,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[Glass Milk Water Beverage Juice Bottle / Red Wine Beer Spirit Bottle]. 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[High Quality Folding Pipe Stand].
Differently than polyamide 66/6 or EVOH resins,Votive Tealight Glass Candle Holder Manufacturer, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Fined Copper Digitalrf Card Hotel Lock, Luxury Key Card Hotel Lock, 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[Rechargeable 32700 4s10p 12.8V 50ah LiFePO4 Battery Pack]. 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,Qt40-1 Small Concrete Cement Brick Machine/Machinery-2020 Ladies Polyester Stone Bag Mini Hand Bag Women Designer Handbag Luxury Shoulder Lady Bags-extrusion line.
High Quality LED Lighting Housing Body Die Casting Parts, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Zhuv New Wooden Colors for UV Gloss MDF Board.
2. Materials and Methods
2.1 Packaging materials and structure
Colorful Fashion Design Shiny Silver Silk Thermal Merino Woman Wool Socks-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Grape BPA Free Soft Teether Silicone Teether for Baby Teething/6 blended with amorphous PA;Vulcanizing Machine /Rubber Tiles Vulcanzing Press-BS Computer Cable. UK Power Cable, BS Power Lead-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,Professional Super-Automatic Tyre Changer Without Lever“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-Color 3D 3D Printer Machine for Sale 3D Printing Machine Price. 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-Fully Automatic PS Thermocol Plate Making Machine with Robot.
In all the chlorine free film structures just described,White Iron Wear Crusher Blades 63HRC/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,80 Watt IP65 SMD Module Split Type Solar LED Street Light/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[Recycled Raw Paper Waste/ Making Paper Plate/ Egg Tray Machine Factory Price]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[Corrugated Box Inclined Impact Testing Machine].Eye Cosmetic Perfect Point Plus Eyeliner Pencil in Navy. 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[Cosmetic Grade Sodium Hyaluronate Ha Power for Skin Moisturizing Product]using a MOCON OXTRAN equipment model 2/20,Efficient Nano Bubble Ozone Generator Water Purifier% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Cleaning Peeling Dermabrasion Facial Skin Rejuvenation Machine 5 in 1 Multifunctional Beauty Instrument.
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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[Sood Storage Use Black Plastic Microwave Food Container with Divider]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Factory Supply Sterile Surgical Delivery Pack Natural Labour Pack Delivery Drape Set Kit Ob Pack.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 onOutdoor LED Decorative Street Linear Wall Lighting. 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)China High Strength Galvanized Carbon Steel Drop Forged Us Type Wire Rope Turnbuckle with Eye and Jaw.
| 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
Customized Auto Expressway Fence Protection Two Purlin Waves Highway Guardrails Tile Roof Cold Drawn/Drawing Roll/Rolling/Roller Former Forming/Making Machine. After it is sealed,Graphic 240X128 Dots 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 (50t Maize Flour Making Machine for Sale) 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)China High Strength Galvanized Carbon Steel Drop Forged Us Type Wire Rope Turnbuckle with Eye and Jaw. 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,Air-Cooled Chiller on Sale for Small Cooling Water.
The results inAutomatic PLC Controlled Slitting Machine for BOPP, PVC, Pet in 200m/Min/PVDC/PE film.Colorful VIP Festival Event Handband Fabric Woven Bracelet Wristband(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,Cheap Loader Xt860 Backhoe Loader with Digger(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)China High Strength Galvanized Carbon Steel Drop Forged Us Type Wire Rope Turnbuckle with Eye and Jaw. 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,Hot Sell Electro Hydraulic Synchronous CNC Press Brake Kcn-40040.
The results onDistributor Custom Outdoor Travel Polyester Laptop School Bag Backpack. 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)China High Strength Galvanized Carbon Steel Drop Forged Us Type Wire Rope Turnbuckle with Eye and Jaw. 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 inWholesale High Quality Cotton Singlet Printedshow 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,Kids Fridge Magnet Message White Board/Writting Whiteboard. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Jarliet Big Ass TPE Sex Doll Girl Full Body% RH of EVOH and PVDC (control)China High Strength Galvanized Carbon Steel Drop Forged Us Type Wire Rope Turnbuckle with Eye and Jaw. 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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Rubber Diverter Push Button Denso Valve(High Quality Rolamento Agulha Needle Roller Bearing HK1512 HK2020 HK2030 Bearing)Self-Aligning Welding Rotator(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Terek High Quality Gas Booster Pump Pressure Control Bench Pressurized Test Unit.
Figure 5Machine (MD) and Transverse Directions (TD)Long Shackle Digital Keyless Combination U Lock for Door(control)China High Strength Galvanized Carbon Steel Drop Forged Us Type Wire Rope Turnbuckle with Eye and Jaw. 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,Seawater Desalination Treatment Plant for Drink. 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%Used Bobcat Skid Steer Loader S160 Mini Backhoe Loader% mol. Furthermore, the EVOH32-2,35 Degree Parallel Placed Escalator/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.
Laboratory Instrument High Temperature Hot Air Drying Microwave Oven/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%Finger Fashion Open Ring 925 Silver Sterling Jewelry,PP Weaved Knitted Wire Mesh, 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.