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  1. The 828-metre (2,717 ft) tall Burj Khalifa in Dubai has been the tallest building since 2010. The Burj Khalifa has been classified as megatall. A diagram showing the tallest buildings as of 2024 This is a list of the tallest buildings.Tall buildings, such as skyscrapers, are intended here as enclosed structures with continuously occupiable floors and a height of at least 340 metres (1,120 ft).

  2. en.wikipedia.org › wiki › Burj_KhalifaBurj Khalifa - Wikipedia

    The Burj Khalifa [a] (known as the Burj Dubai prior to its inauguration) is a skyscraper in Dubai, United Arab Emirates. It is the world's tallest structure. With a total height of 829.8 m (2,722 ft, or just over half a mile) and a roof height (excluding antenna, but including a 242.6 m spire) [2] of 828 m (2,717 ft), the Burj Khalifa has been ...

  3. en.wikipedia.org › wiki › SwastikaSwastika - Wikipedia

    The swastika is a symbol with many styles and meanings and can be found in many cultures. The appropriation of the swastika by the Nazi Party is the most recognisable modern use of the symbol in the Western world. The swastika (卐 or 卍) is an ancient religious and cultural symbol, predominantly found in various Eurasian cultures, as well as some African and American ones.

    • History
    • Chemical and Physical Properties
    • Production
    • Manufacturing from Polypropylene
    • Applications
    • Repairing
    • Health Concerns
    • Combustibility
    • External Links

    Phillips Petroleum chemists J. Paul Hogan and Robert Banks first demonstrated the polymerization of propylene in 1951. The stereoselective polymerization to the isotactic was discovered by Giulio Natta and Karl Rehn in March 1954. This pioneering discovery led to large-scale commercial production of isotactic polypropylene by the Italian firm Monte...

    Polypropylene is in little aspects similar to polyethylene, especially in solution behavior and electrical properties. The methyl group improves mechanical properties and thermal resistance, although the chemical resistance decreases.: 19 The properties of polypropylene depend on the molecular weight and molecular weight distribution, crystallinity...

    Polypropylene is produced by the chain-growth polymerization of propene: The industrial production processes can be grouped into gas phase polymerization, bulk polymerization and slurrypolymerization. All state-of-the-art processes use either gas-phase or bulk reactor systems. 1. In gas-phase and slurry-reactors, the polymer is formed around hetero...

    Melting process of polypropylene can be achieved via extrusion and molding. Common extrusion methods include production of melt-blown and spun-bond fibers to form long rolls for future conversion into a wide range of useful products, such as face masks, filters, diapers and wipes. The most common shaping technique is injection molding, which is use...

    As polypropylene is resistant to fatigue, most plastic living hinges, such as those on flip-top bottles, are made from this material. However, it is important to ensure that chain molecules are oriented across the hinge to maximise strength. Polypropylene is used in the manufacturing of piping systems, both ones concerned with high purity and ones ...

    PP objects can be joined with a two-part epoxyglue or using hot-glue guns. PP can be melted using a speed tip weldingtechnique. With speed welding, the plastic welder, similar to a soldering iron in appearance and wattage, is fitted with a feed tube for the plastic weld rod. The speed tip heats the rod and the substrate, while at the same time it p...

    The advocacy organization Environmental Working Group classifies PP as of low to moderate hazard.[why?]PP is dope-dyed; no water is used in its dyeing, in contrast with cotton.

    Like all organic compounds, polypropylene is combustible. The flash point of a typical composition is 260 °C; autoignition temperatureis 388 °C.

  4. en.wikipedia.org › wiki › StoicismStoicism - Wikipedia

    Stoicism is a school of Hellenistic philosophy that flourished in Ancient Greece and Ancient Rome. [1] The Stoics believed that the practice of virtue is enough to achieve eudaimonia: a well-lived life. The Stoics identified the path to achieving it with a life spent practicing the four virtues in everyday life: wisdom, courage, temperance or ...

  5. en.wikipedia.org › wiki › MaldivesMaldives - Wikipedia

    The Maldives is the smallest country in Asia. Including the sea, the territory spans roughly 90,000 square kilometres (35,000 sq mi), and a land area of 298 square kilometres (115 sq mi). The Maldives is one of the world's most geographically dispersed sovereign states, and the smallest Muslim-majority country by land area.

  6. The Internet of things (IoT) describes devices with sensors, processing ability, software and other technologies that connect and exchange data with other devices and systems over the Internet or other communications networks.[1][2][3][4][5] The Internet of things encompasses electronics, communication, and computer science engineering ...

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