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System Of A Down - Toxicity
 
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System of a Down's official music video for 'Toxicity'. Click to listen to System of a Down on Spotify: http://smarturl.it/SystemSpotify?IQid=SystemToxicity As featured on Toxicity. Click to buy the track or album via iTunes: http://smarturl.it/SystemToxicity?IQid=SystemToxicity Google Play: http://smarturl.it/ToxicityGPlay?IQid=SystemToxicity Amazon: http://smarturl.it/ToxicityAmazon?IQid=SystemToxicity More from System of a Down Chop Suey!: https://youtu.be/CSvFpBOe8eY Aerials: https://youtu.be/L-iepu3EtyE B.Y.O.B: https://youtu.be/zUzd9KyIDrM More great Alternative videos here: http://smarturl.it/Alternative00?IQid=SystemToxicity Follow System of a Down Website: http://www.systemofadown.com/ Facebook: https://www.facebook.com/systemofadown Twitter: https://twitter.com/systemofadown Instagram: https://instagram.com/systemofadown/ Subscribe to System of a Down on YouTube: http://smarturl.it/SYODSub?IQid=SystemToxicity --------- Lyrics: Conversion, software version 7.0 Looking at life through the eyes of a tire hub Eating seeds as a pastime activity The toxicity of our city, of our city New, what do you own the world? How do you own disorder, disorder Now, somewhere between the sacred silence, sacred silence and sleep Somewhere between the sacred silence and sleep Disorder, disorder, disorder More wood for their fires, loud neighbours Flashlight reveries caught in the headlights of a truck Eating seeds as a pastime activity The toxicity of our city, of our city
Views: 339737985 systemofadownVEVO
Tata Lpt 3118c Stuck in Mud Rescue By Jcb Machine.
 
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Bricks load tata lpt truck Is passing through the mud road in rainy days. The condition of the road is very bad,Nevertheless tata 12 wheeler lorry crosses some pits,but the tata motors truck trapped in big pit. In an attempt to remove the lpt truck from the pit,the truck is even more trapped in mud because of overloads. When the truck driver & helper feel that it is difficult to remove the truck from the pit,they call the truck owner and tell the whole story. Truck owner comes to the spot and after seeing the truck status,calls the jcb. After half an hour,jcb 3dx xtra reaches to the scene and gets into work. Initially jcb backhoe try lift the truck by pushing it from the rear,but success is not achieve. Finally the tata 12 wheeler lorry is pulled from backwards,where by the truck comes out from the pit. So watch this great jcb working video. Shop On Amazon - https://amzn.to/2oiZWOg #jcbvideo #tata3118truck #tatatrucks #jcbmachine
Views: 21425016 Entertainment World
What is CRYSTALLINITY? What does CRYSTALLINITY mean? CRYSTALLINITY meaning & explanation
 
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What is CRYSTALLINITY? What does CRYSTALLINITY mean? CRYSTALLINITY meaning - CRYSTALLINITY definition - CRYSTALLINITY explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ Crystallinity refers to the degree of structural order in a solid. In a crystal, the atoms or molecules are arranged in a regular, periodic manner. The degree of crystallinity has a big influence on hardness, density, transparency and diffusion. In a gas, the relative positions of the atoms or molecules are completely random. Amorphous materials, such as liquids and glasses, represent an intermediate case, having order over short distances (a few atomic or molecular spacings) but not over longer distances. Many materials, such as glass-ceramics and some polymers, can be prepared in such a way as to produce a mixture of crystalline and amorphous regions. In such cases, crystallinity is usually specified as a percentage of the volume of the material that is crystalline. Even within materials that are completely crystalline, however, the degree of structural perfection can vary. For instance, most metallic alloys are crystalline, but they usually comprise many independent crystalline regions (grains or crystallites) in various orientations separated by grain boundaries; furthermore, they contain other crystallographic defects (notably dislocations) that reduce the degree of structural perfection. The most highly perfect crystals are silicon boules produced for semiconductor electronics; these are large single crystals (so they have no grain boundaries), are nearly free of dislocations, and have precisely controlled concentrations of defect atoms. Crystallinity can be measured using x-ray crystallography, but calorimetric techniques are also commonly used.
Views: 669 The Audiopedia
Living Polymers in Nanomaterials and Medicines
 
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A brief explanation of the uses of living polymers in nanomedicine. Sources I used: Multifunctional polymeric micelles with folate-mediated cancer cell targeting and pH-triggered drug releasing properties for active intracellular drug delivery - Younsoo Bae, Woo-Dong Jang, Nobuhiro Nishiyama, Shigeto Fukushima and Kazunori Kataoka - Molecular BioSystems Issue 3, 2005: 252-250 Doxorubicin-Loaded Polymeric Micelle Overcomes Multidrug Resistance of Cancer by Double-Targeting Folate Receptor and Early Endosomal pH - Dongin Kim, Eun Seong Lee, Kyung Taek Oh, Zhong Gao Gao, and You Han Bae - Small. 2008 Nov; 4(11): 2043–2050. (Adriamycin loaded micelle with folic acid diagram also taken from here) Nanotechnology: Carrying drugs - Katherine Bourzac - Nature 491: S58–S60 Themed issue: synthesis of polymeric nanomaterials for medicine - Cyrille Boyer and Thomas P. Davis - Polymer Chemistry Issue 5, 2014: 1501-1502 http://www.futuremedicine.com/doi/pdf/10.2217/nnm.11.182 http://www.nanocarrier.co.jp/en/research/pipeline/02.html (Nanoplatin diagram and efficacy graph also taken from here) Images: http://www.newworldencyclopedia.org/entry/Polyethylene (Polyethylene structure) https://cornellbiochem.wikispaces.com/Ethylene (Ethene pic) http://www.esterindustries.com/product.aspx?clink-id=7&mcat-id=54 (Nylon struture) http://www-ics.u-strasbg.fr/etsp/lecture/mchem_poly/glos.php (Kevlar structure) http://what-when-how.com/molecular-biology/polypeptide-chain-molecular-biology/ (Polypeptide general structure) http://www.eastman.com/Markets/Tackifier_Center/Pages/Block_Copolymer.aspx (Block copolymer picture) http://www.sigmaaldrich.com/technical-documents/articles/materials-science/plga-drug-delivery.html (Amphiphilc copolymer structure) http://journal.frontiersin.org/article/10.3389/fphar.2014.00077/full (Drug loaded micelle diagram) https://en.wikipedia.org/wiki/Micelle (Simple micelle diagram) http://www.scbt.com/datasheet-200896-cisplatin.html (Cisplatin structure) https://dermatology.wisc.edu/mukhtar.htm (Tumour blood vessels diagram) http://test.gbiosciences.com/ResearchProducts/Doxorubicin.aspx (Doxorubicin structure) http://www.rsccaerodefense.com/polymer-cross-linking.php (Polyethylene diagram) http://chemwiki.ucdavis.edu/Core/Organic_Chemistry/Organic_Chemistry_With_a_Biological_Emphasis/Chapter_17%3A_Radical_reactions/Section_17.2%3A_Radical_chain_reactions (Radical polymerisation initiation mechanism) https://en.wikipedia.org/wiki/Cationic_polymerization (Cationic polymerisation initiation mechanism) Both the anionic polymerisation initiation and propagation steps were drawn by me using ChemDraw software.
Views: 428 Luke Reeve
Yaar Jigree Kasooti Degree | Episode 4 - Interconnection | Punjabi Web Series 2018 | Troll Punjabi
 
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Here we present you the Episode 4 of "Yaar Jigri Kasuti Degree" A Punjabi Tv Web Series written and directed by Rabby Tiwana. In this Ep 4 " Interconnection" Anmol and Daizy will argue with each other over assignment row; Ekam & Jass will discover a common interest between them; Roop and Keerat meets Simran; Lucky flirts with Jessica; Whereas Lalli as usual nashe di lorr ch lol U-Dictionary Download Link : https://https://udictionary.page.link/yaarjigreekasootidegreeudsep18 Episode 4 Cast :- Written & Directed by Rabby Tiwana (Insta : @rabbytiwana) (Email - [email protected] Contact No. +919569453006) Starring :- Pukhraj Bhalla (Insta : @pukhrajbhalla), Sukhdeep Sapra (Insta : @sukhdeep_sapra_official ), Karan Sandhawalia (Insta : @karansandhawalia ), Amrit Amby (Insta : @amritamby), Jasmin Bajwa (Insta : @jasminbajwa22 ) , Pawan Johal (Insta : @ipawanjohal ), Prateek Singh Rai (Insta : @prateek.singh.rai ) Karanvir Deol(Insta : @karan.deol ) Co-Starring :- Sukhi Patran, Sukhchain Singh, Chamkaur Billa, Baabar Khan, Hashneen Chauhan, Charanpreet Maan, Satnam Dhuri, Dalveer Dill, Nirbhay Dhaliwal, Enayat Jugnu Surjit, Meet Kaur, Bhindi Tolewal, Baabar Khan, Surinder Sager, Kaka Kautki, Sagun Bhullar, Mohan Kamboj, Jagjit Singh, Rang Harjinder, Charanjeet Kaur, Shivranjini Sharda, Asawari Sharda, Jagdeesh Papda, Jasvir Kaur, Mani Lubana, Harinder Hundal, Pooja Kaithwas and many Yaar Jigree Kasoti Degree Punjabi TV Serial Crew of Episode Four:- Cinematographer - Gagandeep Singh Sarao Casting - Sukhchain Singh Editing - Rabby Tiwana & Prince K. Makkar Background Score - Sarang Sikander 1st Camera Assistant - Karanveer Singh Monga & Paramveer Sharma 2nd Camera Assistant - Robin Robbie & Manish Bhardhwaj Asst. Director - Mohit Kapoor Script Supervisor - Smyle Sachdeva & Karan Kamra VFX - Diljot Garcha, Simardeep Garcha Singers - Sharry Maan, Sardool Sikander, Sarang Sikander, Preet Hundal, Daman Kaushal, Pukhraj Bhalla, Karan Sandhawalia, Rabia Sagoo & Harinder Samra Music Composers - Mista Baaz, Sarang Sikander, Preet Hundal, Sharan Shergill, Kru172, Dreamboy & JT Bhatti Sound Recordist - Narbhey Singh Atwal Foley - Rabby Tiwana, Alaap Sikander & Husandeep Mehal. Production Managers - Asis Anshuman Mohapatara, Gurkirat Virk & Sukhjinder Singh Making & Still - Prince K. Makkar & Sukhmeet Dahiya Makeup - Siddhi Kamboj & Pushpinder Sharma Publicity Design - Mehange Bande yaar jigri kasuti degree episode 4 #YJKD #trollpunjabi #5thEp13Oct Follow Yaar Jigri Kasuti Degree :- Like us on FB - https://www.facebook.com/YaarJigreeKasootiDegree/ Follow us on Insta - https://www.instagram.com/yaar_jigree_kasooti_degree/ Troll Punjabi :- Like us on FB - https://www.facebook.com/troll.punjabi/ Follow us on Insta - https://www.instagram.com/troll_punjabi/ Snapchat - troll-punjabi
Views: 9812976 Troll Punjabi
What does electropolymerization mean?
 
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What does electropolymerization mean? A spoken definition of electropolymerization. Intro Sound: Typewriter - Tamskp Licensed under CC:BA 3.0 Outro Music: Groove Groove - Kevin MacLeod (incompetech.com) Licensed under CC:BA 3.0 Intro/Outro Photo: The best days are not planned - Marcus Hansson Licensed under CC-BY-2.0 Book Image: Open Book template PSD - DougitDesign Licensed under CC:BA 3.0 Text derived from: http://en.wiktionary.org/wiki/electropolymerization
Explain Configuration and Conformation | Stereochemistry | Organic Chemistry
 
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Download our Android app at https://goo.gl/5JM1G2 Stereochemistry: It is a branch of chemistry which deals with the 3 dimensional arrangements of different atoms of a molecule with respect to each other in a space around it. Configuration of an organic molecule represents an exact 3D arrangement of all the atom in a molecule with respect to each other. e.g. consider a molecule of methane with molecular formula CH4. Its 2D and 3D configurations are Conformation: Conformation can be discussed only for those organic molecules which posses at least two carbon atom is directly attached with each other. e. G. Consider a molecule of ethane C2H6. It has been observed that the entire molecule of ethane can undergo different structural arrangements / changes just by single bond rotation. Different structural arrangement obtained as a result of free rotation around C -C single bond are treated as the conformation of that molecule, more over the relative study of stability of different conformation possible for same molecule is known as conformational analysis. For Details Visit http://cepekmedia.co.nf http://cepek.hol.es/ http://edmerls.66Ghz.com/ http://edmerls.tk/
Views: 8776 Cepek Media
Stereoregular Meaning
 
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Video shows what stereoregular means. Having small regularly oriented units in a single sequential arrangement.. Stereoregular Meaning. How to pronounce, definition audio dictionary. How to say stereoregular. Powered by MaryTTS, Wiktionary
Views: 337 ADictionary
EICHER TRACTORS - THE MEANING OF POWER
 
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Tractors are generally associated with power. But the EICHER range of tractors from TMTL - TAFE Motors and Tractors Limited are not just about power, but way beyond that. Power is not only about HP or muscle, it means a lot more. Power must be meaningful and with a sense of purpose. The ad, featuring the brand-ambassador of EICHER Tractors and Olympic medalist Sushil Kumar, captures the this expression beautifully. Watch the video NOW! http://eichertractors.tmtl.in http://tafe.com http://tafecafe.com https://www.facebook.com/TAFECorporate https://www.linkedin.com/company/TAFE---Tractors-and-Farm-Equipment-Limited https://plus.google.com/+TAFETractors/posts https://in.pinterest.com/TAFECorporate https://www.flickr.com/photos/[email protected]
Views: 234274 TAFECorporate
Branching (polymer chemistry) | Wikipedia audio article
 
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This is an audio version of the Wikipedia Article: https://en.wikipedia.org/wiki/Branching_(polymer_chemistry) 00:02:05 1 Special types of branched polymer 00:03:25 2 Branching in radical polymerization 00:05:37 3 Branching index Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago. Learning by listening is a great way to: - increases imagination and understanding - improves your listening skills - improves your own spoken accent - learn while on the move - reduce eye strain Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone. Listen on Google Assistant through Extra Audio: https://assistant.google.com/services/invoke/uid/0000001a130b3f91 Other Wikipedia audio articles at: https://www.youtube.com/results?search_query=wikipedia+tts Upload your own Wikipedia articles through: https://github.com/nodef/wikipedia-tts Speaking Rate: 0.9822041450093175 Voice name: en-AU-Wavenet-A "I cannot teach anybody anything, I can only make them think." - Socrates SUMMARY ======= In polymer chemistry, branching occurs by the replacement of a substituent, e.g., a hydrogen atom, on a monomer subunit, by another covalently bonded chain of that polymer; or, in the case of a graft copolymer, by a chain of another type. Branched polymers have more compact and symmetrical molecular conformations, and exhibit intra-heterogeneous dynamical behavior with respect to the unbranched polymers. In crosslinking rubber by vulcanization, short sulfur branches link polyisoprene chains (or a synthetic variant) into a multiply branched thermosetting elastomer. Rubber can also be so completely vulcanized that it becomes a rigid solid, so hard it can be used as the bit in a smoking pipe. Polycarbonate chains can be crosslinked to form the hardest, most impact-resistant thermosetting plastic, used in safety glasses.Branching may result from the formation of carbon-carbon or various other types of covalent bonds. Branching by ester and amide bonds is typically by a condensation reaction, producing one molecule of water (or HCl) for each bond formed. Polymers which are branched but not crosslinked are generally thermoplastic. Branching sometimes occurs spontaneously during synthesis of polymers; e.g., by free-radical polymerization of ethylene to form polyethylene. In fact, preventing branching to produce linear polyethylene requires special methods. Because of the way polyamides are formed, nylon would seem to be limited to unbranched, straight chains. But "star" branched nylon can be produced by the condensation of dicarboxylic acids with polyamines having three or more amino groups. Branching also occurs naturally during enzymatically-catalyzed polymerization of glucose to form polysaccharides such as glycogen (animals), and amylopectin, a form of starch (plants). The unbranched form of starch is called amylose. The ultimate in branching is a completely crosslinked network such as found in Bakelite, a phenol-formaldehyde thermoset resin.
Views: 7 wikipedia tts
What Is The Meaning Of Extracellular?
 
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Extracellular matrix (video) what is extracellular matrix? What does fluid dictionary definition vocabulary. Extracellular isn't just a way to refer the outside of cell there's whole lot going on out there that has do with growth, work, extracellular definition situated or occurring cells. Learn more 28 jul 2015liquid containing proteins and electrolytes including the liquid in blood plasma interstitial fluid situated or taking place outside a cell cells meaning, pronunciation, example sentences, from oxford dictionaries extracellular. Definition of extracellular by medical dictionarydefinition fluid dictionary. And this devidef into two the interstitial fluid and means between cells; The other is inter intracellular digestionthe digestion of food occurs within cellthe outside cell in cavity alimentary 20 may 2013 extracellular bacteria bacterial pathogens do not invade proliferate instead environment which. Definition from wiktionary, the free dictionary. See more medical definition of extracellular. Meaning, pronunciation, translations and examples extracellular fluid in biology, body that is not contained cells. It is found in blood, lymph, body cavities lined with serous (moisture exuding) read medical definition of extracellular located or occurring outside a cell cells fluid meaning, definition, what the space surrounding. Occurring or found outside of a cell the extracellular fluid this is cells. Extracellular definition and meaning wordnik. This space is usually taken to be outside the plasma membranes, and occupied by fluid (see extracellular matrix). Extracellular meaning in the cambridge english dictionary. Extracellular wikipediadefine extracellular at dictionary definition of by merriam websterextracellular. The term is used in contrast to intracellular (inside the cell) extracellular definition, outside a cell or cells. Extracellular wikipedia in cell biology, molecular biology and related fields, the word extracellular (or sometimes space) means 'outside cell'. Extracellular definition of extracellular in english what is the difference between fluid and intracellular distinguish saral study. Extracellular and intracellular bacteria their preferred growth. Situated or occurring outside a cell the cells of body extracellular digestion enzymes 24 jun 2009 for example, fluid is found (or cells) in contrast to intracellular which inside looking online definition medical dictionary? Extracellular explanation free. Extracellular definition & structures extracellular and meaning fluid medical of medicinenet. Extracellular (not comparable). What is extracellular? Meaning of extracellular medical fluid (ecf),the interstitial and the plasma, constituting about 20. Jump to adjective[edit].
Views: 97 Bun Bun 3
Polymer | Wikipedia audio article
 
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This is an audio version of the Wikipedia Article: https://en.wikipedia.org/wiki/Polymer 00:02:36 1 Common examples 00:04:05 2 Synthesis 00:05:47 2.1 Biological synthesis 00:06:38 2.2 Modification of natural polymers 00:07:50 3 Properties 00:08:45 3.1 Monomers and repeat units 00:09:56 3.2 Microstructure 00:10:33 3.2.1 Polymer architecture 00:11:36 3.2.2 Chain length 00:13:49 3.2.3 Monomer arrangement in copolymers 00:15:58 3.2.4 Tacticity 00:16:26 3.3 Morphology 00:16:42 3.3.1 Crystallinity 00:18:23 3.3.2 Chain conformation 00:18:52 3.4 Mechanical properties 00:19:12 3.4.1 Tensile strength 00:19:46 3.4.2 Young's modulus of elasticity 00:20:34 3.5 Transport properties 00:20:56 3.6 Phase behavior 00:21:04 3.6.1 Melting point 00:21:41 3.6.2 Glass transition temperature 00:22:13 3.6.3 Mixing behavior 00:24:40 3.6.4 Inclusion of plasticizers 00:25:34 3.7 Chemical properties 00:27:35 3.8 Optical properties 00:28:36 4 Standardized nomenclature 00:29:39 5 Characterization 00:31:38 6 Degradation 00:34:12 6.1 Product failure Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago. Learning by listening is a great way to: - increases imagination and understanding - improves your listening skills - improves your own spoken accent - learn while on the move - reduce eye strain Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone. Listen on Google Assistant through Extra Audio: https://assistant.google.com/services/invoke/uid/0000001a130b3f91 Other Wikipedia audio articles at: https://www.youtube.com/results?search_query=wikipedia+tts Upload your own Wikipedia articles through: https://github.com/nodef/wikipedia-tts "There is only one good, knowledge, and one evil, ignorance." - Socrates SUMMARY ======= A polymer (; Greek poly-, "many" + -mer, "part") is a large molecule, or macromolecule, composed of many repeated subunits. Due to their broad range of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass relative to small molecule compounds produces unique physical properties, including toughness, viscoelasticity, and a tendency to form glasses and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (polus, meaning "many, much") and μέρος (meros, meaning "part"), and refers to a molecule whose structure is composed of multiple repeating units, from which originates a characteristic of high relative molecular mass and attendant properties. The units composing polymers derive, actually or conceptually, from molecules of low relative molecular mass. The term was coined in 1833 by Jöns Jacob Berzelius, though with a definition distinct from the modern IUPAC definition. The modern concept of polymers as covalently bonded macromolecular structures was proposed in 1920 by Hermann Staudinger, who spent the next decade finding experimental evidence for this hypothesis.Polymers are studied in the fields of biophysics and macromolecular science, and polymer science (which includes polymer chemistry and polymer physics). Historically, products arising from the linkage of repeating units by covalent chemical bonds have been the primary focus of polymer science; emerging important areas of the science now focus on non-covalent links. Polyisoprene of latex rubber is an example of a natural/biological polymer, and the polystyrene of styrofoam is an example of a synthetic polymer. In biological contexts, essentially all biological macromolecules—i.e., proteins (polyamides), nucleic acids (polynucleotides), and polysaccharides—are purely polymeric, or are composed in large part of polymeric components—e.g., isoprenylated/lipid-modified glycoproteins, where small lipidic molecules and oligosaccharide modifications occur on the polyamide backbone of the protein.The simplest theoretical models for polymers are ideal chains.
Views: 4 wikipedia tts
Branching (chemistry) | Wikipedia audio article
 
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This is an audio version of the Wikipedia Article: https://en.wikipedia.org/wiki/Branching_(polymer_chemistry) 00:02:09 1 Special types of branched polymer 00:03:32 2 Branching in radical polymerization 00:05:49 3 Branching index Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago. Learning by listening is a great way to: - increases imagination and understanding - improves your listening skills - improves your own spoken accent - learn while on the move - reduce eye strain Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone. Listen on Google Assistant through Extra Audio: https://assistant.google.com/services/invoke/uid/0000001a130b3f91 Other Wikipedia audio articles at: https://www.youtube.com/results?search_query=wikipedia+tts Upload your own Wikipedia articles through: https://github.com/nodef/wikipedia-tts Speaking Rate: 0.96470202252444 Voice name: en-US-Wavenet-E "I cannot teach anybody anything, I can only make them think." - Socrates SUMMARY ======= In polymer chemistry, branching occurs by the replacement of a substituent, e.g., a hydrogen atom, on a monomer subunit, by another covalently bonded chain of that polymer; or, in the case of a graft copolymer, by a chain of another type. Branched polymers have more compact and symmetrical molecular conformations, and exhibit intra-heterogeneous dynamical behavior with respect to the unbranched polymers. In crosslinking rubber by vulcanization, short sulfur branches link polyisoprene chains (or a synthetic variant) into a multiply branched thermosetting elastomer. Rubber can also be so completely vulcanized that it becomes a rigid solid, so hard it can be used as the bit in a smoking pipe. Polycarbonate chains can be crosslinked to form the hardest, most impact-resistant thermosetting plastic, used in safety glasses.Branching may result from the formation of carbon-carbon or various other types of covalent bonds. Branching by ester and amide bonds is typically by a condensation reaction, producing one molecule of water (or HCl) for each bond formed. Polymers which are branched but not crosslinked are generally thermoplastic. Branching sometimes occurs spontaneously during synthesis of polymers; e.g., by free-radical polymerization of ethylene to form polyethylene. In fact, preventing branching to produce linear polyethylene requires special methods. Because of the way polyamides are formed, nylon would seem to be limited to unbranched, straight chains. But "star" branched nylon can be produced by the condensation of dicarboxylic acids with polyamines having three or more amino groups. Branching also occurs naturally during enzymatically-catalyzed polymerization of glucose to form polysaccharides such as glycogen (animals), and amylopectin, a form of starch (plants). The unbranched form of starch is called amylose. The ultimate in branching is a completely crosslinked network such as found in Bakelite, a phenol-formaldehyde thermoset resin.
Views: 2 wikipedia tts
Conductive polymer
 
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If you find our videos helpful you can support us by buying something from amazon. https://www.amazon.com/?tag=wiki-audio-20 Conductive polymer Conductive polymers or, more precisely, intrinsically conducting polymers (ICPs) are organic polymers that conduct electricity.Such compounds may have metallic conductivity or can be semiconductors. =======Image-Copyright-Info======= Image is in public domain Author-Info: Smokefoot Image Source: https://en.wikipedia.org/wiki/File:ConductivePoly.png =======Image-Copyright-Info======== -Video is targeted to blind users Attribution: Article text available under CC-BY-SA image source in video https://www.youtube.com/watch?v=wQsOKbKmnuA
Views: 3131 WikiAudio
Polymer | Wikipedia audio article
 
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This is an audio version of the Wikipedia Article: Polymer 00:02:36 1 Common examples 00:04:05 2 Synthesis 00:05:46 2.1 Biological synthesis 00:06:37 2.2 Modification of natural polymers 00:07:50 3 Properties 00:08:44 3.1 Monomers and repeat units 00:09:55 3.2 Microstructure 00:10:31 3.2.1 Polymer architecture 00:11:34 3.2.2 Chain length 00:13:40 3.2.3 Monomer arrangement in copolymers 00:15:48 3.2.4 Tacticity 00:16:16 3.3 Morphology 00:16:32 3.3.1 Crystallinity 00:18:12 3.3.2 Chain conformation 00:18:42 3.4 Mechanical properties 00:19:02 3.4.1 Tensile strength 00:19:35 3.4.2 Young's modulus of elasticity 00:20:23 3.5 Transport properties 00:20:45 3.6 Phase behavior 00:20:54 3.6.1 Melting point 00:21:30 3.6.2 Glass transition temperature 00:22:02 3.6.3 Mixing behavior 00:24:29 3.6.4 Inclusion of plasticizers 00:25:23 3.7 Chemical properties 00:27:24 3.8 Optical properties 00:28:24 4 Standardized nomenclature 00:29:27 5 Characterization 00:31:48 6 Degradation 00:34:22 6.1 Product failure Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago. Learning by listening is a great way to: - increases imagination and understanding - improves your listening skills - improves your own spoken accent - learn while on the move - reduce eye strain Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone. You can find other Wikipedia audio articles too at: https://www.youtube.com/channel/UCuKfABj2eGyjH3ntPxp4YeQ You can upload your own Wikipedia articles through: https://github.com/nodef/wikipedia-tts "The only true wisdom is in knowing you know nothing." - Socrates SUMMARY ======= A polymer (; Greek poly-, "many" + -mer, "part") is a large molecule, or macromolecule, composed of many repeated subunits. Due to their broad range of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass relative to small molecule compounds produces unique physical properties, including toughness, viscoelasticity, and a tendency to form glasses and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (polus, meaning "many, much") and μέρος (meros, meaning "part"), and refers to a molecule whose structure is composed of multiple repeating units, from which originates a characteristic of high relative molecular mass and attendant properties. The units composing polymers derive, actually or conceptually, from molecules of low relative molecular mass. The term was coined in 1833 by Jöns Jacob Berzelius, though with a definition distinct from the modern IUPAC definition. The modern concept of polymers as covalently bonded macromolecular structures was proposed in 1920 by Hermann Staudinger, who spent the next decade finding experimental evidence for this hypothesis.Polymers are studied in the fields of biophysics and macromolecular science, and polymer science (which includes polymer chemistry and polymer physics). Historically, products arising from the linkage of repeating units by covalent chemical bonds have been the primary focus of polymer science; emerging important areas of the science now focus on non-covalent links. Polyisoprene of latex rubber is an example of a natural/biological polymer, and the polystyrene of styrofoam is an example of a synthetic polymer. In biological contexts, essentially all biological macromolecules—i.e., proteins (polyamides), nucleic acids (polynucleotides), and polysaccharides—are purely polymeric, or are composed in large part of polymeric components—e.g., isoprenylated/lipid-modified glycoproteins, where small lipidic molecules and oligosaccharide modifications occur on the polyamide backbone of the protein.The simplest theoretical models for polymers are ideal chains.
Views: 4 wikipedia tts
Mod-01 Lec-24 Polymer Stereochemistry and Coordination Polymerization (Contd.)
 
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Polymer Chemistry by Dr. D. Dhara,Department of Chemistry and Biochemistry,IIT Kharagpur.For more details on NPTEL visit http://nptel.ac.in
Views: 1953 nptelhrd
What does homopolymerization mean?
 
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What does homopolymerization mean? A spoken definition of homopolymerization. Intro Sound: Typewriter - Tamskp Licensed under CC:BA 3.0 Outro Music: Groove Groove - Kevin MacLeod (incompetech.com) Licensed under CC:BA 3.0 Intro/Outro Photo: The best days are not planned - Marcus Hansson Licensed under CC-BY-2.0 Book Image: Open Book template PSD - DougitDesign Licensed under CC:BA 3.0 Text derived from: http://en.wiktionary.org/wiki/homopolymerization Text to Speech powered by TTS-API.COM
वेजिटेबल बिरयानी (Vegetable Biryani) by Tarla Dalal
 
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Vegetable Biryani,a most popular and common rice dish. Recipe link : http://www.tarladalal.com/Vegetable-Biryani-(-Chawal)-37251r Subscribe : http://goo.gl/omhUio Tarla Dalal App: http://www.tarladalal.com/free-recipe-app.aspx Facebook: http://www.facebook.com/pages/TarlaDalal/207464147348 YouTube Channel: http://www.youtube.com/user/TarlaDalalsKitchen/featured Pinterest: http://www.pinterest.com/tarladalal/ Google Plus: https://plus.google.com/107883620848727803776 Twitter: https://twitter.com/Tarla_Dalal Tarla Dalal Blogspot: http://tarladalal.blogspot.in/ Vegetable Biryani Vegetable biryani is the most popular and the most common rice dish that comes to one's mind when you think of indian cuisine. . . It is very tasty and definately worth a try ! Preparation Time: 15 minutes Cooking Time: 55 minutes Soakeing Time : 30 minutes Makes 6 servings Ingredients For The Rice 1 bayleaf (tejpatta) 25 mm (1") stick cinnamon (dalchini) 1 clove 1 cardamom (elaichi) 1 1/2 cups long grained rice ( basmati), soaked for 30 minutes and drained salt to taste For The Vegetable Gravy 1 1/2 cups boiled mixed vegetables (carrots , peas , cauliflower , french beans , potatoes) cut into cubes 1/4 cup paneer (cottage cheese) , cut into cubes 2 tbsp oil 1/2 tsp cumin seeds (jeera) 3/4 cup finely chopped onions 2 tsp ginger-green chilli paste 1/4 tsp turmeric powder (haldi) 2 tsp coriander (dhania) powder 1 tsp chilli powder 1/2 tsp garam masala 1 cup roughly chopped tomatoes salt to taste 1/4 cup milk a pinch of sugar Other Ingredients 1/4 cup curds (dahi) 1/4 cup finely chopped coriander (dhania) a few drops of edible saffron colour 2 tbsp ghee Method For the rice 1. Combine 4 1/2 cups of water, bayleaf, cinnamon, clove, cardamom, rice and salt in a deep non-stick pan and cover and cook on a medium flame for 10 minutes or till the rice is cooked. 2. Strain the rice using a strainer and keep aside. For the vegetable gravy 1. Heat the oil in a kadhai and add the cumin seeds. 2. When the seeds crackle, add the onions and sauté on a medium flame for 1 to 2 minutes or till the onions turn translucent. 3. Add the ginger-green chilli paste, turmeric powder, coriander powder, chilli powder and garam masala and sauté on a medium flame for a few seconds. 4. Add the tomatoes and 2 tbsp of water, mix well and cook on a medium flame for 4 to 5 minutes. 5. Add the mixed vegetables, paneer, salt and milk and cook on a medium flame for another 2 to 3 minutes, while stirring occasionally. 6. Add the sugar, mix well and cook on a medium flame for 1 more minute. How to proceed 1. Combine the curds, coriander and saffron colour in a bowl and mix well. 2. Add the prepared rice mixture and mix well. 3. Transfer 1/2 of the rice mixture in a handi and spread it evenly with the back of a spoon. 4. Add all the prepared vegetable gravy on it and spread it evenly. 5. Top it with the remaining 1/2 of the rice mixture and spread it evenly. 6. Pour the ghee evenly over it and cover it with a lid. 7. Place the handi on a non-stick tava (griddle) and cook on a slow flame for 25 to 30 minutes. 8. Serve hot.
Views: 1406095 Tarla Dalal
What does stereospecific polymer mean?
 
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What does stereospecific polymer mean? A spoken definition of stereospecific polymer. Intro Sound: Typewriter - Tamskp Licensed under CC:BA 3.0 Outro Music: Groove Groove - Kevin MacLeod (incompetech.com) Licensed under CC:BA 3.0 Intro/Outro Photo: The best days are not planned - Marcus Hansson Licensed under CC-BY-2.0 Book Image: Open Book template PSD - DougitDesign Licensed under CC:BA 3.0 Text derived from: http://en.wiktionary.org/wiki/stereospecific_polymer
Gharapudhe Thambla Tanga | Superhit Marathi Balgeet 2018 | Kids Songs by Jingle Toons
 
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Gharapudhe Thambla Tanga, Pahune Kon Kon Ale Sanga Very interesting Marathi Balgeet. Watch the favorite guests coming home in the Tanga. Jingle Toons brings the memorable moments and guest in the form of animation. Song from "Chandoba Chandoba" album.
Views: 13507530 Jingletoons Marathi
Jodi thake nosibe Chisty Baul | Baul Songit | Chisty Baul | ONE VERSUS ALL
 
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Jodi thake nosibe Chisty Baul | Baul Songit | Chisty Baul | ONE VERSUS ALL Please all of my friends subscribe my channel
Views: 1170635 ONE VERSUS ALL
What is GLASS TRANSITION? What does GLASS TRANSITION mean? GLASS TRANSITION meaning & explanation
 
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What is GLASS TRANSITION? What does GLASS TRANSITION mean? GLASS TRANSITION meaning - GLASS TRANSITION definition - GLASS TRANSITION explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. The glass–liquid transition or glass transition for short is the reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. An amorphous solid that exhibits a glass transition is called a glass. The reverse transition, achieved by supercooling a viscous liquid into the glass state, is called vitrification. The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs. It is always lower than the melting temperature, Tm, of the crystalline state of the material, if one exists. Hard plastics like polystyrene and poly(methyl methacrylate) are used well below their glass transition temperatures, that is in their glassy state. Their Tg values are well above room temperature, both at around 100 °C (212 °F). Rubber elastomers like polyisoprene and polyisobutylene are used above their Tg, that is, in the rubbery state, where they are soft and flexible. Despite the change in the physical properties of a material through its glass transition, the transition is not considered a phase transition; rather it is a phenomenon extending over a range of temperature and defined by one of several conventions. Such conventions include a constant cooling rate (20 kelvins per minute (36 °F/min)) and a viscosity threshold of 1012 Pa·s, among others. Upon cooling or heating through this glass-transition range, the material also exhibits a smooth step in the thermal-expansion coefficient and in the specific heat, with the location of these effects again being dependent on the history of the material. The question of whether some phase transition underlies the glass transition is a matter of continuing research. The glass transition of a liquid to a solid-like state may occur with either cooling or compression. The transition comprises a smooth increase in the viscosity of a material by as much as 17 orders of magnitude without any pronounced change in material structure. The consequence of this dramatic increase is a glass exhibiting solid-like mechanical properties on the timescale of practical observation. This transition is in contrast to the freezing or crystallization transition, which is a first-order phase transition in the Ehrenfest classification and involves discontinuities in thermodynamic and dynamic properties such as volume, energy, and viscosity. In many materials that normally undergo a freezing transition, rapid cooling will avoid this phase transition and instead result in a glass transition at some lower temperature. Other materials, such as many polymers, lack a well defined crystalline state and easily form glasses, even upon very slow cooling or compression. The tendency for a material to form a glass while quenched is called glass forming ability. This ability depends on the composition of the material and can be predicted by the rigidity theory. Below the transition temperature range, the glassy structure does not relax in accordance with the cooling rate used. The expansion coefficient for the glassy state is roughly equivalent to that of the crystalline solid. If slower cooling rates are used, the increased time for structural relaxation (or intermolecular rearrangement) to occur may result in a higher density glass product. Similarly, by annealing (and thus allowing for slow structural relaxation) the glass structure in time approaches an equilibrium density corresponding to the supercooled liquid at this same temperature. Tg is located at the intersection between the cooling curve (volume versus temperature) for the glassy state and the supercooled liquid.
Views: 7286 The Audiopedia
What is RANDOM COIL INDEX? What does RANDOM COIL INDEX mean? RANDOM COIL INDEX meaning
 
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What is RANDOM COIL INDEX? What does RANDOM COIL INDEX mean? RANDOM COIL INDEX meaning - RANDOM COIL INDEX definition - RANDOM COIL INDEX explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel - https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ Random coil index (RCI) predicts protein flexibility by calculating an inverse weighted average of backbone secondary chemical shifts and predicting values of model-free order parameters as well as per-residue RMSD of NMR and molecular dynamics ensembles from this parameter. The key advantages of this protocol over existing methods of studying protein flexibility are 1. it does not require prior knowledge of a protein's tertiary structure, 2. it is not sensitive to the protein's overall tumbling and 3. it does not require additional NMR measurements beyond the standard experiments for backbone assignments. The application of secondary chemical shifts to characterize protein flexibility is based on an assumption that the proximity of chemical shifts to random coil values is a manifestation of increased protein mobility, while significant differences from random coil values are an indication of a relatively rigid structure. Even though chemical shifts of rigid residues may adopt random coil values as a result of comparable contributions of shielding and deshielding effects (e.g. from torsion angles, hydrogen bonds, ring currents, etc.), combining the chemical shifts from multiple nuclei into a single parameter allows one to decrease the influence of these flexibility false positives. The improved performance originates from the different probabilities of random coil chemical shifts from different nuclei being found among amino acid residues in flexible regions versus rigid regions. Typically, residues in rigid helices or rigid beta-strands are less likely to have more than one random coil chemical shift among their backbone shifts than residues in mobile regions. The actual calculation of the RCI involves several additional steps including the smoothing of secondary shifts over several adjacent residues, the use of neighboring residue corrections, chemical shift re-referencing, gap filling, chemical shift scaling and numeric adjustments to prevent divide-by-zero problems. 13C, 15 N and 1H secondary chemical shifts are then scaled to account for the characteristic resonance frequencies of these nuclei and to provide numeric consistency among different parts of the protocol. Once these scaling corrections have been done, the RCI is calculated. The ‘‘end-effect correction’’ can also be applied at this point. The last step of the protocol involves smoothing the initial set of RCI values by three-point averaging.
Views: 84 The Audiopedia
Polyethylene Terephthalate (PET)
 
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Title: Polyethylene Terephthalate (PET) Description: This video is a project for Chemistry in Sacred Heart School - Ateneo de Cebu. This video will provide you informations about Polyethylene terephthalate, which is popularly used for packaging purposes and also in fibers for clothing. The video talks about its chemical formula, structure and components. It includes about how Polyethylene terephthalate is formed and its properties. Also, it shows the different uses, application and environmental effect. Lastly, this video talks about the pros and cons of Polyethylene terephthalate. #shsadcgenchem #mrsnarca The group gathered sources from the internet. One member was tasked to create the video using the information and pictures that the group collected. The assigned member uses iMovie to create and edit the short video. Script: Polyethylene Terephthalate (Picture of PET Resin) Chemical Formula (with picture) Components: 10 Carbon, 8 Hydrogen and 4 Oxygen How is it formed? (Picture of Terephthalic acid) + (Picture of Ethylene Glycol) = Polyethylene Terephthalate Properties of PET It is a hard, stiff, strong, dimensionally stable material that absorbs very little water. It has good gas barrier properties and good chemical resistance except to alkalis (which hydrolyse it). Its crystallinity varies from amorphous to fairly high crystalline. PET can be highly transparent and colourless but thicker sections are usually opaque and off-white. (Picture of properties) Uses of PET PET containers are popular for packaging sodas, water, juices, salad dressings, cooking oil, peanut butter, shampoo, tennis balls etc. PET resin is also used in fabrics for clothing. (Picture of PET's uses) Application of PET Like glass, PET is hygienic, strong, resistant to attack by micro-organisms, does not react with foods or beverages, and will not biologically degrade. Its safety for food and beverage use is recognized by health authorities around the world. But unlike glass, PET is extremely lightweight, simple to transport and won't break, which is why it's preferred for packaging many foods and beverages. Although PET bottles are approved for both single and repeated use, the refilling and re-use of any bottle first requires careful cleaning. Always use soap and hot water. Dry thoroughly to make sure it is free of any moisture that might promote bacterial growth. Consumers should avoid re-using any bottle that has been scratched inside, since bacteria can become lodged in scratches. Environmental Effect (Logo of PET as recycling material) PET is a remarkably energy-efficient packaging material, with an environmental impact that compares very favorably to glass, aluminum and other container materials. Although PET's feedstocks are derived from crude oil and natural gas, approximately 40% of that energy is trapped within the PET polymer for recapture and reuse every time PET is recycled. And because PET is very strong yet lightweight, it allows more product to be delivered with less packaging, less weight and less fuel for transport. (Picture of Pros and Cons) ✔️Easily recycled Durable and safe to use Doesn't react with foods Positive environmental effects Comes in a variety of shapes and colors. Low transmission rates between inside and outside of container slows oxidation and evaporation of products. Shatterproof and ideal for slippery bathroom ✖️PET has a low heat tolerance. If sanitized with a Hydrogen Peroxide solution , water marks can be left on the containers as they dry. Credits: iMovie theme music (Travel) For pictures: http://f.tqn.com/y/chemistry/1/W/v/l/2/formulas-157378066.jpg https://s3.amazonaws.com/skooli-wp/wp-content/uploads/2015/02/why_is_chemistry_so_hard.jpg http://s3-ap-southeast-1.amazonaws.com/subscriber.images/cbse/2016/03/12081121/Chemistry-leaked2.jpg https://chemistry.georgetown.edu/sites/chemistry/files/styles/rotator_image_overlay_unit_profile/public/molecules.jpg Sources: Source 1: https://en.m.wikipedia.org/wiki/Polyethylene_terephthalate Source 2: http://www.petresin.org Source 3: http://www.azom.com/article.aspx?ArticleID=2047 Submitted by: Bowenn Sy, Isabella Alyssa Marie Pil, Shajanna Claire Tan 11-Humilitas
Views: 5722 Shajanna Tan
DAK DIYACHEN DOYAL AMARE
 
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androw kishor
Views: 1304934 mahk136
Stereospecific polymer Meaning
 
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Video shows what stereospecific polymer means. A polymer that has a specific spatial arrangements of its constituent atoms, leading to an almost crystalline structure. stereospecific polymer synonyms: stereoregular polymer. Stereospecific polymer Meaning. How to pronounce, definition audio dictionary. How to say stereospecific polymer. Powered by MaryTTS, Wiktionary
Views: 674 ADictionary
Sonare Sonare kache aynare।।Kids Songs | Baby Songs | Don't Miss Video
 
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Sonare Sonare kache aynare।।Kids Songs | Baby Songs | Don't Miss Video 2017 Sonare Sonare kache aynare।।Kids Songs | Baby Songs | Don't Miss Video 2017 আপনাদের এই ভিডিও কেমন লাগছে তা লাইক কমেন্ড করে জানাবেন। আমার চেনেল সাবচক্রাইব করবেন। Please Subscrbe Channel............... https://www.youtube.com/channel/UCL8K... Facebook_https://www.facebook.com/groups/1086019908245357/?ref=bookmarks @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ -----------------------------------KEYWORD-------------------------------
Views: 35234 MY YOUTUBE
What is ADDITION POLYMER? What does ADDITION POLYMER mean? ADDITION POLYMER meaning & explanation
 
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What is ADDITION POLYMER? What does ADDITION POLYMER mean? ADDITION POLYMER meaning - ADDITION POLYMER definition - ADDITION POLYMER explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. An addition polymer is a polymer which is formed by an addition reaction, where many monomers bond together via rearrangement of bonds without the loss of any atom or molecule under specific conditions of heat, pressure, and/or the presence of a catalyst. This is in contrast to a condensation polymer which is formed by a condensation reaction where a molecule, usually water, is lost during the formation. An addition polymer is formed by a reaction known as polyaddition or addition polymerization. This can occur in a variety of ways including free radical polymerization, cationic polymerization, anionic polymerization and coordination polymerization. Most of the common addition polymers are formed from unsaturated monomers (usually having a double bond). This includes polyethenes, polypropylene, PVC, Teflon, Buna rubbers, polyacrylates, polystyrene, and PCTFE. Addition polymers are also formed from monomers that have a closed ring. Through coordination polymerization, even saturated monomers can form addition polymers. When two or more types of monomer undergo addition polymerization, the polymer formed is known as an addition copolymer. Saran wrap, formed from polymerization of vinyl chloride and vinylidene chloride, is an addition copolymer. With exception of combustion, the backbone of addition polymers are generally chemically inert. This is due to the very strong C-C and C-H bonds and lack of polarisation within many addition polymers. For this reason they are non-biodegradable and hard to recycle. This is, again, in contrast to condensation polymers which are bio-degradable and can be recycled. Many exceptions to this rule are products of ring-opening polymerization, which tends to produce condensation-like polymers even though it is an additive process. For example, poly is chemically identical to polyethylene glycol except that it is formed by opening ethylene oxide rings rather than eliminating water from ethylene glycol. Nylon 6 was developed to thwart the patent on nylon 6,6, and while it does have a slightly different structure, its mechanical properties are remarkably similar to its condensation counterpart. One universal distinction between polymerization types is development of molecular weight by the different modes of propagation. Addition polymers form high molecular weight chains rapidly, with much monomer remaining. Since addition polymerization has rapidly growing chains and free monomer as its reactants, and condensation polymerization occurs in step-wise fashion between monomers, dimers, and other smaller growing chains, the effect of a polymer molecule's current size on a continuing reaction is profoundly different in these two cases. This has important effects on the distribution of molecular weights, or polydispersity, in the finished polymer. The first useful addition polymer was made by accident in 1933 by ICI chemists Reginald Gibson and Eric Fawcett. They were carrying out a series of experiments which involved reacting organic compounds under high temperatures and high pressures. They set up an experiment to react ethene with benzaldehyde in the hope of producing a ketone. They left the reaction vessel overnight, and the next morning they found a small amount of a white waxy solid. It was shown later that this solid was polyethylene.
Views: 1865 The Audiopedia
ESP Painting & "Dreams"
 
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A look inside our strange world.. Cobalt-60 After entering a living mammal (such as a human being), some of the 60 Co is excreted in feces. The remainder is taken up by tissues, mainly the liver, kidneys, and bones, where the prolonged exposure to gamma radiation can cause cancer. Over time, the absorbed cobalt is eliminated in urine Used for : As a tracer for cobalt in chemical reactions Sterilization of medical equipment. Radiation source for medical radiotherapy. Cobalt therapy, using beams of gamma rays from 60 Co teletherapy machines to treat cancer, has been widely used since the 1950s. Radiation source for industrial radiography. Radiation source for leveling devices and thickness gauges. Radiation source for pest insect sterilization. As a radiation source for food irradiation and blood irradiation. As a radiation source for laboratory mutagenesis use. As a radiation source for stereoregular polymerization reactions, for example in preparation of syndiotactic polymethyl methacrylate. https://en.wikipedia.org/wiki/Cobalt-60 Stolen cobalt-60 found in Mexico; thieves may be doomed December 5, 2013 https://www.washingtonpost.com/world/stolen-cobalt-60-found-in-mexico-curious-thieves-likely-doomed/2013/12/05/262ef990-5d66-11e3-8d24-31c016b976b2_story.html https://duckduckgo.com/?q=cobalt+60&t=h_&ia=web Mineral industry of Africa https://en.wikipedia.org/wiki/Mineral_industry_of_Africa Central African Mining and Exploration Company https://en.wikipedia.org/wiki/Central_African_Mining_and_Exploration_Company THE COBALT PIPELINE Tracing the path from deadly hand-dug mines in Congo to consumers’ phones and laptops https://www.washingtonpost.com/graphics/business/batteries/congo-cobalt-mining-for-lithium-ion-battery/ https://duckduckgo.com/?q=cobalt+60+in+africa&t=h_&ia=web 1,100-year-old Mayan ruins found in North Georgia http://www.rawstory.com/2011/12/1100-year-old-mayan-ruins-found-in-north-georgia/ Pyramids in Florida and Georgia Constructed by Mayans? http://www.mayainamerica.com/2012/01/pyramids-in-florida-and-georgia.html Kenimer Site https://en.wikipedia.org/wiki/Kenimer_Site https://duckduckgo.com/?q=pyramids+in+georgia&t=h_&ia=web https://www.google.com/search?q=Kenimer+Mound&oq=Kenimer+Mound&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8 Georgia Guidestones https://en.wikipedia.org/wiki/Georgia_Guidestones Elbert County, Georgia https://en.wikipedia.org/wiki/Elbert_County,_Georgia
Views: 50 Reblyn Bradley
Hindi Essay on 'Dr Sarvepalli Radhakrishnan' | 'डा0 सर्वपल्ली राधाकृष्णन' पर निबंध
 
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Essay | निबन्ध is a Channel developed especially for online free essays, articles, speeches, debates, biographies, stories & poems in Hindi and English languages. There are many videos in various categories and topics which may help the kids and students. This Channel is an effort to bring it viewers with the best possible essays, articles, speeches, debates, biographies, stories & poems on variety of topics. Please Like, comment and Subscribe to show your support and for more videos......All likes/ dislikes, comments, shares and subscribers are appreciated. THANK YOU!!!!! You may read text version of related essays at my blogs--- English Essay► http://all-essay.blogspot.in/ Facebook► https://www.facebook.com/All-Essay-561719073853471/ Twitter► https://twitter.com/all_essay Google+► https://plus.google.com/117008186045777807329 Hindi Essay► http://hindi-essay.blogspot.in/ Facebook► https://www.facebook.com/Hindi-Essay-303284096461209/ Twitter► https://twitter.com/hindiessay Google+► https://plus.google.com/110850739187943423288
Crystallization of polymers
 
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Crystallization of polymers is a process associated with partial alignment of their molecular chains. These chains fold together and form ordered regions called lamellae, which compose larger spheroidal structures named spherulites. Polymers can crystallize upon cooling from the melt, mechanical stretching or solvent evaporation. Crystallization affects optical, mechanical, thermal and chemical properties of the polymer. The degree of crystallinity is estimated by different analytical methods and it typically ranges between 10 and 80%, thus crystallized polymers are often called 'semicrystalline'. The properties of semicrystalline polymers are determined not only by the degree of crystallinity, but also by the size and orientation of the molecular chains. Polymers are composed of long molecular chains which form irregular, entangled coils in the melt. Some polymers retain such a disordered structure upon freezing and thus convert into amorphous solids. In other polymers, the chains rearrange upon freezing and form partly ordered regions with a typical size of the order 1 micrometer. Although it would be energetically favorable for the polymer chains to align parallel, such alignment is hindered by the entanglement. Therefore, within the ordered regions, the polymer chains are both aligned and folded. Those regions are therefore neither crystalline nor amorphous and are classified as semicrystalline. Examples of semi-crystalline polymers are linear polyethylene, polyethylene terephthalate, polytetrafluoroethylene or isotactic polypropylene. Whether or not polymers can crystallize depends on their molecular structure – presence of straight chains with regularly spaced side groups facilitates crystallization. For example, crystallization occurs much easier in isotactic than in the atactic polypropylene form. Atactic polymers crystallize when the side groups are very small, as in polyvinyl and don't crystallize in case of large substituents like in rubber or silicones. Nucleation starts with small, nanometer-sized areas where as a result of heat motion some chains or their segments occur parallel. Those seeds can either dissociate, if thermal motion destroys the molecular order, or grow further, if the grain size exceeds a certain critical value. Apart from the thermal mechanism, nucleation is strongly affected by impurities, dyes, plasticizers, fillers and other additives in the polymer. This is also referred to as heterogeneous nucleation. This effect is poorly understood and irregular, so that the same additive can promote nucleation in one polymer, but not in another. Many of the good nucleating agents are metal salts of organic acids, which themselves are crystalline at the solidification temperature of the polymer solidification. Crystal growth is achieved by the further addition of folded polymer chain segments and only occurs for temperatures below the melting temperature Tm and above the glass transition temperature Tg. Higher temperatures destroy the molecular arrangement and below the glass transition temperature, the movement of molecular chains is frozen. Nevertheless, secondary crystallization can proceed even below Tg, in the time scale of months and years. This process affects mechanical properties of the polymers and decreases their volume because of a more compact packing of aligned polymer chains. The chains interact via various types of the van der Waals forces. The interaction strength depends on the distance between the parallel chain segments and it determines the mechanical and thermal properties of the polymer. Video Empire produces videos read aloud. Use the information in this video at your own risk. We cannot always guarantee accuracy. This video uses material from https://en.wikipedia.org/wiki/Crystallization_of_polymers, licensed with CC Attribution-ShareAlike 3.0. This video is licensed with CC Attribution-Share-Alike 3.0 https://creativecommons.org/licenses/by-sa/3.0/us/ In order to adapt this content it is required to comply with the license terms. Image licensing information is available via: https://en.wikipedia.org/wiki/Crystallization_of_polymers
Views: 2830 Video Empress