PET has a resin identification code of 1. The technique minimizes patient movement artifacts and decreases scanning times to about 50 to 100 msec. For PET we have found 422 definitions. ADH – antidiuretic hormone, Vasopressin. Starting from bottle flakes, the viscosity can be set via the degree of drying. Q. Finally, the cool dry air leaving the desiccant bed is re-heated in a process heater and sent back through the same processes in a closed loop. The destruction of the hydro peroxide groups is, with other processes, already carried out during the last step of flake treatment for instance by adding H3PO3. Drying is achieved through the use of a desiccant or dryers before the PET is fed into the processing equipment. [13], The PET bottle was patented in 1973 by Nathaniel Wyeth. Polyethylene terephthalate is produced from ethylene glycol and dimethyl terephthalate (DMT) (C6H4(CO2CH3)2) or terephthalic acid.[19]. ACT – activated clotting time. In general, one can say that the processes to make PET bottle flakes from collected bottles are as versatile as the different waste streams are different in their composition and quality. [citation needed], In 2016, it was estimated that 56 million tons of PET are produced each year. It is used in the diagnosis of osteopenia and osteoporosis. PET medical abbreviation meaning with flashcards ICD-10 codes. Number of polyfunctional macromolecules increases. Biaxially oriented PET film (often known by one of its trade names, "Mylar") can be aluminized by evaporating a thin film of metal onto it to reduce its permeability, and to make it reflective and opaque (MPET). [12], In the Soviet Union, PET was first manufactured in the laboratories of the Institute of High-Molecular Compounds of the USSR Academy of Sciences in 1949, and its name "Lavsan" is an acronym thereof (лаборатории Института высокомолекулярных соединений Академии наук СССР). Appreciate any info including how to source free/low cost as money is tight. My nose plugged and I had to blow almost constantly. The number of possible impurities and material defects that accumulate in the polymeric material is increasing permanently—when processing as well as when using polymers—taking into account a growing service lifetime, growing final applications and repeated recycling. PET, like many plastics, is also an excellent candidate for thermal disposal (incineration), as it is composed of carbon, hydrogen, and oxygen, with only trace amounts of catalyst elements (but no sulfur). One field of increasing interest where recycled materials are used is the manufacture of high-tenacity packaging stripes, and monofilaments. Besides chemical contaminants and degradation products generated during first processing and usage, mechanical impurities are representing the main part of quality depreciating impurities in the recycling stream. Tube movements can be linear, curvilinear, circular, elliptical, figure eight, hypocycloidal, or trispiral. On the other hand, crystallization is important in other applications where mechanical and dimensional stability are important, such as seat belts. A PET scan uses a radioactive drug (tracer) to show this activity. The ester bonds in polyethylene terephthalate may be cleaved by hydrolysis, or by transesterification. Possible PET meaning as an acronym, abbreviation, shorthand or slang term vary from category to category. [27] This discovery may prove to be an important step towards the concept of a circular PET economy. PET is subject to various types of degradations during processing. This procedure is known as solid-state crystallization. [28] Proposed mechanisms include leaching of phthalates as well as leaching of antimony. The influence of the microscopic particles, which—because they are many—increase the frequency of defects in the polymer, is relatively greater. The task consists in feeding 10–25% bottle flakes while maintaining the quality of the bottle pellets that are manufactured on the line. Besides this process approval it is nevertheless necessary that any user of such processes has to constantly check the FDA limits for the raw materials manufactured by themselves for their process. FDG-PET is listed in the World's largest and most authoritative dictionary database of abbreviations and acronyms FDG-PET - What does FDG-PET stand for? For example, cyclohexanedimethanol (CHDM) can be added to the polymer backbone in place of ethylene glycol. The intrinsic viscosity of the material, found by extrapolating to zero concentration of relative viscosity to concentration which is measured in deciliters per gram (dℓ/g). I also came down with a sore throat and a bad cough. When filled with glass particles or fibres, it becomes significantly stiffer and more durable. It may also be referred to by the brand names Terylene in the UK,[5] Lavsan in Russia and the former Soviet Union, and Dacron in the US. In April 2020, a French university announced the discovery of a highly efficient, optimized enzyme that outperforms all PET hydrolases reported so far. Besides this external (post-consumer) polyester bottle recycling, numbers of internal (pre-consumer) recycling processes exist, where the wasted polymer material does not exit the production site to the free market, and instead is reused in the same production circuit. Intrinsic viscosity is dependent upon the length of its polymer chains but has no units due to being extrapolated to zero concentration. PET is commonly recycled, and has the number "1" as its resin identification code (RIC). When PET degrades, several things happen: discoloration, chain scissions resulting in reduced molecular weight, formation of acetaldehyde, and cross-links ("gel" or "fish-eye" formation). Thus, before the resin can be processed in a molding machine, it must be dried. The body of the tube is significantly thicker, as it will be inflated into its final shape in the second step using stretch blow molding. Polyethylene Terephthalate (more common than PETE) PET. Medical professionals for humans instead use the term qd (an abbreviation for quaque die). Depending on its processing and thermal history, polyethylene terephthalate may exist both as an amorphous (transparent) and as a semi-crystalline polymer. PET is used as a 3D printing filament, as well as in the 3D printing plastic PETG. All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. Mohawk Industries released everSTRAND in 1999, a 100% post-consumer recycled content PET fiber. Bio-PET is the bio-based counterpart of PET.[6][7]. Q. Common causes of malnutrition are inadequate calorie consumption; inadequate intake of essential vitamins, minerals, or other micronutrients; improper absorption and distribution of foods within the body; overeating; and intoxication by nutrient excesses. A PET bottle which has been heated by a candle and has recrystallized, making it opaque. formation of vinyl ester end groups through dehydration or decarboxylation of terephthalate acid, reaction of the OH- or COOH- end groups with mono-functional degradation products like mono-carbonic acids or alcohols. This compound is purified by vacuum distillation, and is one of the intermediates used in polyester manufacture (see production). For adjusting the viscosity, however, an addition of chain length modifier like ethylene glycol or diethylene glycol can also be used. PET has the energy content of soft coal. Dx has come to be an abbreviation for diagnosis. Antimony also remains in the material itself and can, thus, migrate out into food and drinks. In addition to pure (homopolymer) PET, PET modified by copolymerization is also available. In this case, too, the required viscosity can be adjusted via drying or vacuum adjustment in case of vacuum extrusion. Non-oriented PET sheet can be thermoformed to make packaging trays and blister packs. At room temperature the molecules are frozen in place, but, if enough heat energy is put back into them by heating above Tg, they begin to move again, allowing crystals to nucleate and grow. An injury that has occurred in which one or more of the topmost layers of the skin are scraped away. In order to save costs, an increasing number of polyester intermediate producers like spinning mills, strapping mills, or cast film mills are working on the direct use of the PET-flakes, from the treatment of used bottles, with a view to manufacturing an increasing number of polyester intermediates. The resultant crude terephthalic acid can be purified by recrystallization to yield material suitable for re-polymerization: This method does not appear to have been commercialized yet. The high plasticization temperature of PET in the range of 280 °C (536 °F) is the reason why almost all common organic impurities such as PVC, PLA, polyolefin, chemical wood-pulp and paper fibers, polyvinyl acetate, melt adhesive, coloring agents, sugar, and protein residues are transformed into colored degradation products that, in their turn, might release in addition reactive degradation products. Excess ethylene glycol is distilled off at higher temperature with the aid of vacuum. Pharmacology and Experimental Therapeutics (journal) PET. PETG can be colored during processing. Can a pet allergy cause your nose to plug, give you a sore throat and a bad cough? These properties are useful in many applications, including flexible food packaging and thermal insulation (such as space blankets). After manufacturing, a detectable amount of antimony can be found on the surface of the product. Definition A positron emission tomography (PET) scan is an imaging test that allows your doctor to check for diseases in your body. With regard to the consumption of PET bottle flakes, the main portion of about 70% is converted to fibers and filaments. An examination from head to toe of the body with computed tomographic imaging, promoted as a screening test for cancer and other illnesses. Terylene (a trademark formed by inversion of (polyeth)ylene ter(ephthalate)) is also spliced into bell rope tops to help prevent wear on the ropes as they pass through the ceiling. The treatment of polyester waste through total glycolysis to fully convert the polyester to bis(2-hydroxyethyl) terephthalate (C6H4(CO2CH2CH2OH)2). The reactions are simply the reverse of those used in production. [23] [19], In the terephthalic acid process, esterification of ethylene glycol and terephthalic acid is conducted directly at moderate pressure (2.7–5.5 bar) and high temperature (220–260 °C). Author: Angela M Alleman Created Date: Dry, heated compressed air is circulated through the PET pellets as in the desiccant dryer, then released to the atmosphere. [citation needed], Japanese scientists have isolated a bacterium Ideonella sakaiensis that possesses two enzymes which can break down the PET into smaller pieces that the bacterium can digest. In order to protect the spinnerets, an efficient filtration of the melt is, in any case is necessary. MSD and the MSD Veterinary Manual Merck & Co., Inc., Kenilworth, NJ, USA (known as MSD outside of the US and Canada) is a global healthcare leader working to help the world be well. Fertility - In stud dogs, the ability to impregnate the female. What does PET stand for in Military? [20] It uses a radioactive substance called a tracer to look for disease in the body. Top PET acronym definition related to defence: Performance Evaluation Tool Reactive polyester OH- or COOH- end groups are transformed into dead or non-reactive end groups, e.g. A radiographic technique that selects a level in the body and blurs out structures above and below that plane, leaving a clear image of the selected anatomy. One way to alleviate this is to use a copolymer. Once freed of the impurities, the oligomers can be fed back into the production process for polymerization. and Bashir, Z. The role of this procedure is to detect metabolically active malignant lesions including lung cancer, colorectal cancer, lymphoma, melanoma, breast cancer, ovarian cancer, brain cancer and multiple myeloma. The WHO has published a risk assessment for antimony in drinking water. PET-Recycling Forum; "Current Technological Trends in Polyester Recycling"; 9th International Polyester Recycling Forum Washington, 2006; São Paulo; Boos, Frank and Thiele, Ulrich "Reprocessing pulverised polyester waste without yellowing", German Patent, Learn how and when to remove this template message, Polycyclohexylenedimethylene terephthalate, Institute for Occupational Safety and Health, "poly(ethylene terephthalate) macromolecule_msds", Bio-based drop-in, smart drop-in and dedicated chemicals, Duurzame bioplastics op basis van hernieuwbare grondstoffen, SIPA: Lightweight compressed gas cylinders have plastic liners / PET provides high oxygen barrier, Ullmann's Encyclopedia of Industrial Chemistry, "Could a new plastic-eating bacteria help combat this pollution scourge? Recycled materials are increasingly introduced into manufacturing processes, which were originally designed for new materials only. This is accomplished by moving the x-ray tube in the opposite direction from the imaging device around a stationary fulcrum defining the plane of interest. It is characterized by: Persistent high blood pressure at or above 140/90mmHg. Because of the recyclability of PET and the relative abundance of post-consumer waste in the form of bottles, PET is rapidly gaining market share as a carpet fiber. Free. This is because drying the material in less than 4 hours would require a temperature above 160 °C, at which level hydrolysis would begin inside the pellets before they could be dried out. Therefore, efficient sorting, separation and cleaning processes become most important for high quality recycled polyester. It is a clear amorphous thermoplastic that can be injection-molded, sheet-extruded or extruded as filament for 3D printing. Choosing the re-pelletizing way means having an additional conversion process that is, at the one side, energy-intensive and cost-consuming, and causes thermal destruction. Antimony (Sb) is a metalloid element that is used as a catalyst in the form of compounds such as antimony trioxide (Sb2O3) or antimony triacetate in the production of PET. The chemical recycling where transesterification takes place and other glycols/polyols or glycerol are added to make a polyol which may be used in other ways such as polyurethane production or PU foam production, PET bottle collection and waste separation: waste logistics, Production of clean bottle flakes: flake production, Conversion of PET flakes to final products: flake processing, Sorting and selection for different colors, foreign polymers especially PVC, foreign matter, removal of film, paper, glass, sand, soil, stones, and metals, Coarse cutting dry or combined to pre-washing, Air sifting to remove film, paper, and labels, Removal of low-density polymers (cups) by density differences, Caustic wash, and surface etching, maintaining intrinsic viscosity and decontamination, Water circuit and water treatment technology. PET works as a much better barrier to oxygen than earlier used (LD)PE.[10]. [citation needed], "PETE" redirects here. Depending on purity of the recycled materials, polyester can be used today in most of the polyester manufacturing processes as blend with virgin polymer or increasingly as 100% recycled polymer. Reconstruction of brain sections by using positron-emitting radionuclides. The success of any recycling concept is hidden in the efficiency of purification and decontamination at the right place during processing and to the necessary or desired extent. [clarification needed][citation needed] Then, the number of defects in the polymer chain increases considerably. PET is also used as a waterproofing barrier in undersea cables. In dimethyl terephthalate(DMT) process, this compound and excess ethylene glycol are reacted in the melt at 150–200 °C with a basic catalyst. Staple fibers are spun in an intrinsic viscosity range that lies rather somewhat lower and that should be between 0.58 and 0.62 dℓ/g. (2002) Chapter 7, p. 320 in Fakirov, Stoyko (ed.). This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. Recycling processes with polyester are almost as varied as the manufacturing processes based on primary pellets or melt. The current owner of the trademark is DuPont Teijin Films US, a partnership with a Japanese company. It is achieved by digital processing of x-ray attenuation coefficients from a 360° wedge scan of ionizing radiation. Dx: Most of us are familiar with the abbreviation Rx, for prescriptions, which is thought to come from the Latin “recipere,” or recipe. Prevention, Education and Training. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world. Helpful, trusted answers from doctors: Dr. Fried on pet medical abbreviation: it is recommended that you see your doctor in 1 to 2 weeks after your abortion you ensure that the procedure has been completed and you are no longer pregnant. Number, concentration, and variety of nonpolymer-identical organic and inorganic foreign substances are increasing. abscess. Return to: Medical Student Instruction Below is a list of abbreviations that you may see while rotating on the otolaryngology service: ABR: auditory brainstem response; ACC: adenoid cystic carcinoma Polyester makes up about 18% of world polymer production and is the fourth-most-produced polymer after polyethylene (PE), polypropylene (PP) and polyvinyl chloride (PVC). Results are decreased reactivity during re-polycondensation or re-SSP and broadening the molecular weight distribution. 'President Elect Training Seminar' is one option -- get in to view more @ The Web's largest and most authoritative acronyms and abbreviations resource. In conventional radiology, tomographic images (body section radiographs) are produced by motion of the x-ray tube and film or by motion of the patient that blurs the image except in a single plane. abrasion. This process consists of transforming bottle waste into flakes, by drying and crystallizing the flakes, by plasticizing and filtering, as well as by pelletizing. Pre-eclamptic toxaemia (PET) is also called Toxemia of Pregnancy or pregnancy induced hypertension. Depending on composition and impurity level of input material, the general following process steps are applied.[37]. Special feature are: Acetaldehyde and oligomers are contained in the pellets at lower level; the viscosity is reduced somehow, the pellets are amorphous and have to be crystallized and dried before further processing. Commentary published in Environmental Health Perspectives in April 2010 suggested that PET might yield endocrine disruptors under conditions of common use and recommended research on this topic. Cost-efficiency can already be achieved with plant capacities within a range of 5000–20,000 tons/year. Veterinary technicians should be able to understand those abbreviations and convert them into drug labels or instructions that pet owners will understand. The additional use of TiO2 is necessary for full dull or semi dull yarn. The drinking water limit assessed by WHO is 20 parts per billion (WHO, 2003), and the drinking water limit in the United States is 6 parts per billion. See copolymers, above. [32] The prime uses for recycled PET are polyester fiber, strapping, and non-food containers.[32]. The highest rates appear red, those lower appear yellow, then green, and the lowest rates appear blue. Typically, residual moisture levels in the resin must be less than 50 parts per million (parts of water per million parts of resin, by weight) before processing. High-speed spinning processes for the manufacture of POY normally need a viscosity of 0.62–0.64 dℓ/g. The recycling of PET bottles is meanwhile an industrial standard process that is offered by a wide variety of engineering companies.[38]. These kinds of processes are typical of small and medium-size industry. Based on how it is processed, PET can be semi-rigid to rigid, and it is very lightweight. This step can be more or less complex and complicated depending on required final flake quality. Those abbreviations stand for: fluorodeoxyglucose (FDG)-positron emission tomography (PET). The motto "What the eye does not see the heart cannot grieve over" is considered to be very important in many recycling processes. 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