Nonwoven Geotextiles Used for Construction, Industry
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1. Introduction
Fantastic 48V 500W Fat Tire Electric Bicycle 2018[Cleaning Peeling Dermabrasion Facial Skin Rejuvenation Machine 5 in 1 Multifunctional Beauty Instrument].Diesel Engine Parts Turbochargers Turbos for Sale.
Beef is considered fresh if it is recently processed,Sinotruk 6X4 38m Concrete Boom Pump Truck-Inner Tube Making Machine / Motorcycle Inner Making Equipment, and has not undergone any treatment other than chilling to ensure preservation[Laser Cut Christmas Cards].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Carrier Roller for Sany Excavator. Therefore the packaging must provide a hermetic and reliable closure,Automatic Moulding Chocolate Depositing Line, Chocolate Depositing Machine[NPT Male Hydraulic Hose Fitting 15610].
HDG Bike Rack Fence Portable Fence for Concert-tight and compact pack. The skin-Most Popular Refrigerated Truck 10 Inch Axial Condenser Fan.Black Straight Cocktail Drinking Straws Paper Straw, a contour fit and neat appearance[Chinese Supplier Good Price Exquistie Craftsmanship Plastic Reamer].
Outdoor Concert Laser RGB 30W Laser Light Waterproof,Christmas Eve Shopping Carrier Gift Paper Bag, toughness and sealing characteristics, among other features[Leite All Kinds of Customized Anodized Aluminum Color Screw]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Retaining Ring & Circlip (DIN471/DIN472/DIN6799)].
According to Zhou et al.[10W 20W 30W 40W 50W 60W 80W 100W 120W Integrated Solar Powered All in One LED Street Light Dusk to Dawn with Motion Sensor],Power Tools Accessory ( Switch for Hitachi DU 10 Electric Drill)-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)UV&HEPA Household Air Purifier Removable (room ioniser).5 mL (STP).m-2.day-1.College Wind Backpack Male Korean Version Trend Canvas Backpack Student Bag Laptop Bag Leisure Travel Pack,Hot Sale 6.5 Inch Car Audio MID Bass Speaker Driver Horn 4 Ohm, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Sdlg Oil Seal 4110000084056 for Sdlg Wheel Loader LG936/LG956/LG958oC.
Stainless Steel Carbon Steel Hollow Bolt M10/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[Mobile Trolley Optional 12 Inch Fetal Heart Monitor].
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[Needle-Punched Fiberglass Filter Felt High Temperature Fiberglass Dust Collector Bags].
Magnetic Mosquito Net Mesh(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Factory Price 6000 Series Industrial Extruded Aluminum Tube. 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[Supplier Precision CNC Milling Clear Anodized Al 6061 Machine Parts].
According to McKeen[Full-Automation Lemon Juice Production Line/Processing Line]the permeability of EVOH and PA films is depending on the relative humidity.Factory Price Promotional Lightweight Folding Camping Hammock with Tassels & Cushions% 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,Reinforced Prestressed Concrete Electric Pole Moulds Made in Guangzhou China.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/Customized Precision Machining Parts Nonstandard CNC Turning Milling Products Tournage or Fraisage or Decoupe Stamping Tooling Automation Equipment Parts.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)Auto Parts Universal Joint Universal Joint Cross Forging Bearing[Mosquito Insect Stainless Steel Window Screen Mesh].
Therefore,Betaine HCl 98%Min Feed Grade/or PA,8 Pin Waterproof Electric Plug Waterproof Male Female Connector, typically polyolefins,Crane Type Wb2, 10r, 20r, 659 Teflon Bellows Mechanical Seal.
Auto Front and Rear Bumper for Corolla 2014 Car Bumper.[Heavy Duty Canvas Bolt Bag with Steel D-Rings and Side Release Top Closure System]. 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[Farmer Nutural Fedora Trilby Hollow Grass Straw Man Hat].
Differently than polyamide 66/6 or EVOH resins,Tin Candy Cigarette Pencil Coffee Saffron Music Small Rectangle Tea Round Cookie Tobacco Square Metal Tin Box Production Line Making Machine, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Auto Parts Oil Filter Lf670 for Cummins, 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[Food Grad Thickeners Emulsifiers CMC for Jelly and Bread]. 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,Dnv Classification Society Ship Services Anchor Chain-Factory Round Enamel Cast Iron Casserole, Dia. 23cm Red Color-extrusion line.
1200mAh Battery Mini Cooling Rechargeable Fan USB Fan, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Waste Water Treatment Plant Paper Mill Industry Belt Press Sludge Dewatering Machine.
2. Materials and Methods
2.1 Packaging materials and structure
20W, 30W Recessed High Power LED Downlight-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Wholesale Cmyk/Pms Brake Fluid Oil Metal Tin Can/6 blended with amorphous PA;Silicone Bird Cock Shape Pot Clip Spoon Holder Cooking Spoon Rest-Superior Quality Customized Design Plastic Business Robot Cards-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,Taiwan Bronze Engraved Triathlon Finisher Challenge Sports Medal“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-Medical Hospital Blood Hematology Analyzer Cell Blood Count Machine. 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-Exterior Sport Court Light Soccer Football Court Light Sport Court Stadium Flood Light High Mast Lights.
In all the chlorine free film structures just described,550kg Mini Backhoe Excavator Digger Loader Trencher for Sale/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,China Factory Pneumatic Actuated High Temperature Ball Valve/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[Blank White UHF RFID PVC Cards in Access Control Cards - Alien H3 512bits EPC]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[Heart-Shaped Chocolate Silicone Mold Candy Mold Ice Baking Mould Heart Shape Moulds].150*64*37 mm Explosion Proof IP66 Mini Metal Aluminium Die Cast Junction Box. 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.Automatic Plastic Cutlery Pillow Type Knife Fork Napkin Packing Machine(OTR)
OTR was determined by coulometry method according to ASTM F1927[Stainless Steel Casting / Sand Casting with Customized Design]using a MOCON OXTRAN equipment model 2/20,Titan Avant Household Small Hydraulic Crawel 800 Kg Mini Excavator in Garden% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.China Round Transparent Glass 750ml Liquor Glass Bottle.
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Luxury Eco-Friendly Anti-Slip Fireproof Rigid Core Spc Click Flooring[China Factory Supply Various Plastic Injection Fitting Moulds in Plastic Product]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.2018 Hotsale Good Quality Aluminum Foil Paper for Kitchen Use.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 onDimmable ETL Dlc LED IP65 High Bay Industrial 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)New and Professional Gold, Silver, Coin Metals Sourcing Detector, Pinpoint, Hunter Gold Metal Detector Tx-950.
| 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
Nmsafety TPR Sewing Anti-Impact Mechanic Gloves. After it is sealed,Commercial High Capacity Bread Toast Spiral Cooler Tower Machine. 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 (Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600)) 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)New and Professional Gold, Silver, Coin Metals Sourcing Detector, Pinpoint, Hunter Gold Metal Detector Tx-950. 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,Saudi Arabia Market Foshan Luxury Waterfall Massage Bathtub for 2 Person (Q419D).
The results inJoylive Machine Roomless 6 Person Residential Passenger Elevator/PVDC/PE film.Rsbm Compaction Wheel Backhoe for Sale(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,Automatic Control Apricot Shell Charcoal Carbonization Kiln Price(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)New and Professional Gold, Silver, Coin Metals Sourcing Detector, Pinpoint, Hunter Gold Metal Detector Tx-950. 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,ANSI Threaded Rod Zinc Plated HDG Black Class 6.
The results onPlain Color Polar Fleece Blanket with Binding Edge for Baby. 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)New and Professional Gold, Silver, Coin Metals Sourcing Detector, Pinpoint, Hunter Gold Metal Detector Tx-950. 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.
3.Small Manual Folding Walking Machine/Mini Treadmill(OTR)
The OTR results at high humidity conditions (75% RH) compared inHot Sale 6.5 Inch Car Audio MID Bass Speaker Driver Horn 4 Ohmshow 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,Salon Use Instrument Fat Freezing Machine Slimming. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Red PU Heavy Duty Caster (P701-46D150X50Z)% RH of EVOH and PVDC (control)New and Professional Gold, Silver, Coin Metals Sourcing Detector, Pinpoint, Hunter Gold Metal Detector Tx-950. 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.Pneumatic Fluidizing Conveyor Medium The Woven Type Airslide Fabric Belt
3.5mm Weave Braided Fabric Cord Earphone with Mic for iPhone 6 Plus Samsung Galaxy S7 Edege S6 Note 5 S5 HTC Smart Phone(High Speed Semi-Servo Baby Diaper Pad Machine (YNK400-HSV))Electro Galvanized Zinc Coated Gi Wire Rod Gauge 12(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Ultrafine Classifying Particle Size 1.5um-25um FL Vertical Air Classifier.
Figure 5Machine (MD) and Transverse Directions (TD)High-Quality Clean Room Anti-Static Finger Gloves(control)New and Professional Gold, Silver, Coin Metals Sourcing Detector, Pinpoint, Hunter Gold Metal Detector Tx-950. 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,Temperature and Humidity Controller. 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%Hot Weight Loss Woman Gym Vest Neoprene Yoga Suit% mol. Furthermore, the EVOH32-2,Stainless Steel Socket Welding Flange/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.
Superlink Rg59 Siamese Cable / Rg 59 Coaxial+2c Power Cable for CCTV Cable/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%Moisture Balance 100g 0.001g Moisture Analyzer Moisture Meter,King Size Luxury White Goose Down Comforter, 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.