STS The Nano World PDF

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Introduction Scientific researchers  Developed new technological tools that improve aspects of our lives Nanoscale  One important interdisciplinary area generated by science and technological advancements  About 1 to 100 nanometers Scientists and researchers  Build materials with innovative prop...

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Introduction Scientific researchers  Developed new technological tools that improve aspects of our lives Nanoscale  One important interdisciplinary area generated by science and technological advancements  About 1 to 100 nanometers Scientists and researchers  Build materials with innovative properties by manipulating nanomaterials Nanomaterials  Research: widespread implications in society (health care, environment, energy, food, water,agriculture Nanotechnology  Science, engineering, and technology conducted at the nanoscale Nanoscience and nanotechnology  Study and application of exceptionally small things  Concepts: Started in Dec. 29,1959 o Richard Feyman - physicist; methods in which scientists can direct and control individual atoms and molecules  Talk: “There’s Plentyof Room at the Bottom” o Professor Norio Taniguchi - coined the term “nanotechnology” How Small is a Nanoscale Nanometer - billionth of a meter; 10-9 of a meter Nanomaterials  Manipulation: need an adept understanding of types and dimensions  Classified according to their shapes and sizes How to View Nanomaterials Scientists use special types of microscopes:  Electron microscopes  Field microscopes Modern and remarkable advancements in microscopy:  Scanning tunneling microscopes  Atomic force microscopes 1. Electron Microscope  Ernst Ruska and Max Knoll - German engineers; built the first electron microscopein1930s  Utilizes a particle beam of electrons to light up and develop  Produces a higher and better resolution  Can magnify objects up to million times

 (Conventional light microscopes - magnify up to 1500 times only)  2 general types of electron microscopes: o SEM - Scanning electron microscope o TEM - Transmission electron microscope 2. Atomic Force Microscope  Gerd Binig, Calvin Quate, and Christoph Gerber - developed this in 1986  Makes use of mechanical probe - gathers info from surface of materials 3. Scanning tunneling microscope  Gerd Binig and Heinrich Roher - won the Nobel Prize in Physics bec of this  Special type of microscope that enables scientists to view and manipulate nanoscale particles Nanomanufacturing  Refers to scaled-up, reliable,and costeffective manufacturing of nanoscale  Involves research, improvement,and incorporation  Leads to the development of new products and improved materials Two Fundamental Approaches to nanomanufacturing: 1. Bottom-up fabrication  Build products from atomic-and molecular-scale components  Can be time-consuming  Scientists and engineers are still in search for the effective ways of putting up components that self-assemble 2. Top-down fabrication  Trims down to large pieces of materials into nanoscale  Needs larger amounts of materials and discards excess raw materials New approaches to the assembly of nanomaterials based from the top-down and bottom-up fabrications 1. Dip-pen lithography  Tip of an atomic force microscope is”dipped” into a chemical fluid and then utilized to “write” on a surface 2. Self-assembly  Set of components join together to mold an organized structure in the absence of an outside direction 3. Chemical vapor deposition  Chemicals act in response to form very pure, high-performance films 4. Nanoimprint lithography  Generating nanoscale attributes by “stamping” or “printing” them on a surface 5. Molecular beam epitaxy

 Depositing extremely controlled thin films 6. Roll-to-roll processing  Hgh-volume practice for constructing nanoscale devices on a roll of ultrathin plastic or metal 7. Atomic layer epitaxy  Laying down one-atom-thick layers on a surface  These techniques made nanomaterials more durable, stronger, lighter, waterrepellent, etc. Computers  Near future: better, more efficient, larger storage, faster, energy-saving  Entire memory of a computer will be aved in a single tiny chip Nanotechnology  Construct high-efficiency, low-cost batteries and solar cells Distinct Features of Nanoscale Nanotechnology – operating at a very small dimension; allows scientists to make use of the exceptional optical, chemical, physical, mechanical, and biological qualities of materials 1. Scale at which much biology occurs  Various cell activities at the nanoscale  Deoxyribonucleic acid (DNA) – genetic material of the cell ; only about 2 nanometers in diameter  Hemoglobin – transports oxygen to tissues throughout the body; 5.5 nanometers in diameter  Bio-barcode assay – fairly inexpensive approach for identification of specific disease markers in the blood despite their small number in a particular specimen 2. Scale at which quantum effects dominate properties of materials  Particles with dimensions of 1-100 nanometers have properties significantly discrete from particles of bigger dimensions  Quantum effects – direct the behavior and properties of particles  Size of material = properties  Essential properties of nanoscale that change as a function of size: o Chemical reactivity o Fluorescence o Magnetic permeability o Melting point o Electrical conductivity

Nanoscale gold – yellow-colored element which may appear red or purple;  Gold’s electron – display restricted motion in nanoscale  Nanoscale gold particles – build up in tumors; permit both precise imaging and targeted laser destruction of the tumor 3. Nanoscale materials have far larger surface areas than similar masses of larger-scale materials  Surface area per mass of a material = greater amount of the material comes in contact with another material [ affects the reactivity] Material: Filled with: Result: Total surface 1 cubic Micrometerarea: 6 centimeter sized cubes square (trillion 1012 meters of them) Surface area: 6 square micrometers each 1 cubic 1-nanometer- Total surface centimeter sized cubes area: 6,000 (1012 of square them) maters Surface area: 6 square nanometers each 

Government Funding for Nanotechnology in Different Countries (Dayrit, 2005) US National Nanotechnology Initiative (NNI)– best-known, most-funded program; 2001; 2008 budget: $1.4B; 2009 budget: $1.5B Europe European Commission (EC) – Feb 2008; launched the ENIAC (European Nanoelectronics Initiative Advisory Council) Japan Nanotechnology Research Institute Taiwan Taiwan National Science and Technology Program for Nanoscience and Nanotechnology India Nanotechnology Research and Education Foundation China National center for Nanoscience and Technology Israel Israel National Nanotechnology Initiative Australia Australian Office of Nanotechnology Canada National Institute for

South Korea Thailand Malaysia

Nanotechnology (NINT) Korea National Nanotechnology Initiative National Nanotechnology Center (NANOTEC) National (Malaysia) Nanaotechnology Initiatives or NNI

Possible Applications of Nanotechnology in the Philippines (Dayrit, 2005) 1. ICT and semiconductors 2. Health and medicine 3. Energy 4. Food and agriculture 5. Environment Nanotech Roadmap for the Philippines (funded by PCAS-TRD-DOST) 1. ICT and semiconductors 2. Health and biomedical 3. Energy 4. Food and agriculture 5. Environment 6. Health and environmental risk 7. Nano-metrology 8. Education and public awareness Benefits and Concerns of Using Nanotechnology Nanotechnology – various applications in different sectors of society and environment Addressing Global Challenges Using Nanotechnology – initiative by SalamancaBuentello; accelerate the use of nanotechnology to address critical sustainable development challenges; possible contributions of community to overcome global challenges Concerns that need to be addressed before using and promoting materials derived from nanotechnology (Dayrit, 2005): 1. Nanotechnology is not a single technology; it may become pervasive 2. Nanotechnology seeks to develop new materials with specific properties 3. Nanotechnology may introduce new efficiencies and paradigms 4. It may be complicated to detect its presence unless one has the specialist tools of nanotechnology Benefits and Concerns of the Application of Nanotechnology in Different Areas Example of Areas Possible Concerns Affected by Benefits Nanotechnol ogy Environment - Detection - High

Health

Economy

and removal of contaminants Development of benign industrial processes and materials Improved medicine

- Better products - New jobs

reactivity and toxicity - Pervasive distribution in environment - No nanospecific EPA regulation - Ability to cross cell membranes and translocate in the body - No FDA approval for cosmetics and supplements Redistribution of wealth - Potential cost of cleanups Accessibility to all income levels

Summary Nanotechnology  Advanced interdisciplinary field  Manufactures materials of great help to the improvement  Field that needs to be explored by experts and neophytes  Before engaging with nanotechnology, we need to account the social, ethical, and environmental concerns of using such nanomaterials...