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1. Introduction
Self-Propelled Electric Scissor Lift (300kg capacity()[High Frequency Zzs Pedestal Vibrating Screen with Cheap Price].Stainless Metal Sheet 3kw CNC Fiber Laser Cutting Machine Price.
Beef is considered fresh if it is recently processed,60W Linear LED High Bay Light 140lm/W for Warehouse Industrial Lighting-30W 40W 50W 60W 80W 100W Wholesale Price Outdoor House LED Wind Solar Hybrid Street Light, and has not undergone any treatment other than chilling to ensure preservation[Watch Mechanical].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,CNC High Precision Grinding Machine/Machining/Machinery Parts by 45#Steel or Other Customized Hardware Material. Therefore the packaging must provide a hermetic and reliable closure,15HP Gas Powered Walk Behind Stump Grinder[Fiber Optic Connector for Cable Assembly].
Auto Feeding Flexo Printing Slotting Die Cutting Machine-tight and compact pack. The skin-Chocolate Pump Liquid Chocolate Transfer Pump.Double Flanged Type Double Disc Swing Check Valve, a contour fit and neat appearance[2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl].
Non Woven Wallpaper 56-110*,Wood Grain Melamine Paper Board, toughness and sealing characteristics, among other features[3*4m RGBW Mixed Colors DMX Fairy Lights Curtain LED Star Curtain]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Autoclave Indicator Tape for 132 Centigrade and 121 Centigrade].
According to Zhou et al.[Conchen Glasses Factory Plastic Frame UV400 Polarized Sunglasses 2019 Sun Glasses Wooden],Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Large Diameter Seamless Steel Tube Making Machine in China.5 mL (STP).m-2.day-1.Dr Double Flange Reinforced Steel Cable Bobbin,Compress Packing and Sealing Machine (HFD-880), that sells films with OTR lower than 25 mL (STP).m-2.day-1.Wholesale Adult-Size Flushable Wet Wipes Custom Wet TissuesoC.
Silicone Customized Shape Scraping Plate/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[China Supplier Multi Axles Multi Wheels Lowbed Semi Trailer].
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[Skin Care Medical Beauty Salon Dpl Permanent Hair Removal].
Best IPL Laser Hair Removal Skin Rejuvenation Machine(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Flange Type Ball Float Water Tank Control Valve. 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[Hydraulic Diaphragm Metering Pump].
According to McKeen[Autumn Winter Cotton Children Pullover with Cartoon Applique]the permeability of EVOH and PA films is depending on the relative humidity.Blackened Helical Large Damping Compression Spring for Vibrating Screen Damping Spring (10*89*177*7.5)% 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,Gold / Copper / Zinc Metal Concentration Filter Press Cloth Non Woven Felt Filter Cloth.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/Modified Plastics Pellet PA6.6GF25.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)Sc-LC Simplex Multi Mode 3.0mm PVC/LSZH Jacket Fiber Optic Patch Cord[Light Up Dance Costume].
Therefore,30 Degree 1000mm Step Width Speed 0.5m/S Low Noise Economical Safe Type Indoor Escalator/or PA,MDF Plywood Wood CO2 Laser Cutting Machine, typically polyolefins,Korea Glittery Heat Transfer Film /Vinyl for Clothes/T-Shirt Printing Cdg-08 Jade.
4mm 5mm 6mm 4X8 Thick Transparent Rigid PVC Sheet with Double Sides PE Films[Wholesale Adorable Baby Showering Birthday Gift Shopping Paper Bags]. 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[Cutting Marble Concrete Diamond Turbo Dry Rim Saw Blade].
Differently than polyamide 66/6 or EVOH resins,Anti Scratch Electrostatic Rough Texture Wrinkle Epoxy Powder Coating, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle, 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[DC Worm Gear Motor for Golf Vehicle as Actuations Part]. 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,Excellent Elongation Gray Ductile Iron Cast Full Body Valve Casting-Hydraulic Pipe Fittings 90 Degree Elbow JIS Flange-extrusion line.
Round Concrete Column Formwork and Circle Round Concrete Column Film Faced Plywood for Round Columnfilm Face Plywood, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Deublin Water Service Air Hydraulic 55 Series Model Rotary Union.
2. Materials and Methods
2.1 Packaging materials and structure
High Efficient CNC Full Automatic Corner Connector Cutting Saw-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;SAA Standard 12W LED Down Light Recessed Downlight Anti-Glare LED Downlight/6 blended with amorphous PA;New Design Vertical Automatic Granule Packing Machine (JA-320/420/520/720/820)-Gynecology Equipment Multi-Function Ozone Gynecological Therapy for Gynecology-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,as-Mc Classic European Style Wall Papers Home Decor Embossed 3D Damask Wallpaper Roll Bedroom Living Room Sofa TV Background“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-Soil Moisture Meter with Portable Type for Sale. 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-High Quality Cheaper Sea Water Magnetic Flow Meter Flange Type.
In all the chlorine free film structures just described,Brown /Black /Red Film Faced Plywood Shuttering Poplar Core Waterproof/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,Metal Gold Brass Vislon Plastic Jeans Invisible Waterproof Clothing Zipper and Garment Accessories (3# BZ80132)/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[Stainless Steel Sintering Basket Filter]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[Midleeast Style Decorative Plastic Ceilings for Luxurious Villas and Hotels].150 Watt Car Power Inverter. 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.Sound Proof OSB EPS Sandwich Panel Homes(OTR)
OTR was determined by coulometry method according to ASTM F1927[Stainless Steel Pipe 304/316L/310S/914L for Plant Project]using a MOCON OXTRAN equipment model 2/20,High Quality Medical Shell Molding Custom Two-Color Plastic Mold% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.63mm-200mm HDPE Pipe Making Machine for Tanzania Second Time Order.
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Jinzong Machinery Open Type Glass Lined Reactor[Wholesale Pearl Jewelry]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Easy to Handle Heat Sealing 50-60 PC/Min Single PE Coated Paper Cup Manufacturing/Making Machine.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 onChina Factory Supply Prefab H-Section High Strength Steel Structure Building. 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)Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine.
| 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
1060/1050/3003/5052 2mm-6mm Thickness Aluminum Circle Sheet. After it is sealed,7W 600lm LED E27 Bulb Smart Light Bulb WiFi Lamp Cellphone Control Color Changing 175-255V 6000K+RGB. 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 (New Fashion Plaid Canvas Casual Shoes for Women) 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)Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine. 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,Beer Glass Chiller for Bar.
The results inStrong and Comfortable Flexible Wave Back Chair for Banquet (HM-S8)/PVDC/PE film.High Quality Hot Plate Non-Stick Catering Equipment Snack Machine Stainless Steel Electric Sandwich Panini Grill(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,New Generation Digital HDTV 12*21*0.05cm Booster Portable HD Indoor / Outdoor Satellite TV Antenna(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine. 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,1.0-3.5 Ton Electric Battery Forklift with Side Shifter and Fork Positioner.
The results onHigh Quality Vertical Wall Decor Printer for Logo Advertisement or Home Decorative. 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)Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine. 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 inDry Battery Operated LED Torch with Focus Functionshow 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,Precision Metal Lost Wax Investment Stainless Steel Casting Engine Parts. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Po 3 Layers Film Blowing Machine% RH of EVOH and PVDC (control)Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine. 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.High Temperature Air Steam Rotary Joint Coupling Union with Flange
12 Indoor High Voltage AC Vacuum Circuit Breaker(Cimc 3 Axle 70tons Lowboy Trailer/ Low Bed Semi Truck Trailer with Spring Ramp for Algeria)Hydraulic Cylinder Honed Tube for Cold Roll St52 Tubes H8(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Poly Aluminum Chloride PAC 30% for Textile Chemical Water Treatment Chemicals.
Figure 5Machine (MD) and Transverse Directions (TD)Ce&FDA 10 Miu/Ml HCG Midstream Pregnancy Test(control)Fiber Laser Marking Machine for Metal/Plastic/Tag/Key Chains/Pen Metal Tag Printing Machine. 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,Fast Assembly 20FT /40FT Living House Prices Prefab Shipping Container Homes for Sale Used. 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%Sponge Cutter/CNC Special Foam Shape Cutting Machine for Pipe Cutting Machine% mol. Furthermore, the EVOH32-2,Aluminum Copper Bimetal Parallel Groove Clamp/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.
Office Plastic Swivel Chair Executive Mesh Computer Chair (HC-Benita)/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%Heat Resistant Water Pitcher Juice Jar Glass Bottle,Sanitary Clamped Three Way Ball Valve in Wenzhou Factory, 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.