صفحه محصول - پاورپوینت نانو متر چیست

پاورپوینت نانو متر چیست (pptx) 29 اسلاید


دسته بندی : پاورپوینت

نوع فایل : PowerPoint (.pptx) ( قابل ویرایش و آماده پرینت )

تعداد اسلاید: 29 اسلاید

قسمتی از متن PowerPoint (.pptx) :

What is nanotechnology? A Nanometer There are 1 billion (1,000,000,000) nanometers in 1 meter There are 1 million (1,000,000) micrometers (or microns) in 1 meter A line of ten hydrogen atoms lined up side by side is 1 nanometer long Your finger nail grows 1 nanometer in 1 second The diameter of your hair is approximately 50,000 nanometers The abbreviation for nanometer is “nm” Nanostructures/Nanomaterials Nanostructures are materials that, in at least one dimension, measure approximately 1 – 100 nm Nanostructures or nanomaterials exhibit properties different from their macroscale counterparts (their “big brothers”) such as: Mechanical strength (how hard they are to break) Electrical conductivity (how fast electrons flow through them) Thermal conductivity (how fast heat flows through them) Chemical reactivity (how well/fast they react with other chemicals) Transparency (how well you can see through them) Magnetism (whether or not they are magnetic) … and many more… Microstructures, the cousin to nanostructures, typically measure between 100 nanometers and 100 micrometers in at least one dimension, but likely do not exhibit unique properties like nanostructures do Types Of Nanostructures/Nanomaterials Nanoparticles or nanospheres: nanoscale lengths are measured in all three dimensions Nanotubes or nanowires or nanorods: nanoscale lengths are measured in two dimensions only Nanoscale thin films or ultra-thin films: nanoscale lengths are measured in one dimension only Nanocomposites: a material comprised of many nanoscale inclusions (such as nanoparticles) Nanostructured materials: a material that exhibits a unique structure that can be measured at the nanoscale Common Examples of Nanostructures/Nanomaterials Quantum dots: nanoparticles 2–10 nm in diameter, made from semiconductors, emit light in a specific wavelength range Carbon nanotubes: hollow cylinders one to tens of nanometers in diameter, extremely strong (hard to break), conduct heat faster than any other known material Buckyballs: nanoparticles comprised of exactly 60 carbon atoms (though there are other types), forming a network that resembles a soccer ball Why does this happen? Nanostructures obey the same fundamental laws of the universe as everything else in nature But… some things that are negligible (can be ignored) at big scales cannot be ignored at small scales For example: Imagine you are an electron moving through a “big” copper wire 1 cm in diameter – you may never see the boundaries of the wire because you are so small compared to its diameter Imagine you are an electron moving through a “small” copper wire 1 nm in diameter (more comparable to the electron’s size) – now you bump into the boundaries of the wire often, which affects how you move through that wire Therefore, the 1 nm diameter copper wire exhibits different electrical properties than its macroscale counterpart! So What is Nanotechnology? Nanotechnology is: Comprised of nanomaterials with at least one dimension that measures between approximately 1 and 100 nm Comprised of nanomaterials that exhibit unique properties as a result of their nanoscale size Based on new nanoscale discoveries across the various disciplines of science and engineering The manipulation of these nanomaterials to develop new technologies/applications or to improve on existing ones Used in a wide range of applications from electronics to medicine to energy and more Some Current Applications of Nanotechnology Solar Cells Nanotechnology enhancements provide: Improved efficiencies: novel nanomaterials can harness more of the sun’s energy Lower costs: some novel nanomaterials can be made cheaper than alternatives Flexibility: thin film flexible polymers can be manipulated to generate electricity from the sun’s energy

فایل های دیگر این دسته

مجوزها،گواهینامه ها و بانکهای همکار

دانلود پروژه دارای نماد اعتماد الکترونیک از وزارت صنعت و همچنین دارای قرارداد پرداختهای اینترنتی با شرکتهای بزرگ به پرداخت ملت و زرین پال و آقای پرداخت میباشد که در زیـر میـتوانید مجـوزها را مشاهده کنید