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  2. 2. Nanotechnology Definition Nanotechnology, shortened to "nanotech", is the study of the control of matter on an atomic and molecular scale. Generally nanotechnology deals with structures of the size 100 nanometers or smaller, and involves developing materials or devices within that size. Introduction Nanotechnology is very diverse, ranging from extensions of conventional device physics, to completely new approaches based upon molecular self-assembly, to developing new materials with dimensions on the nanoscale, even to speculation on whether we can directly control matter on the atomic scale. Nanotechnology has the potential to create many new materials and devices with wide- ranging applications, such as in medicine,electronics, and energy production. On the other hand, nanotechnology raises many of the same issues as with any introduction of new technology, including concerns about the toxicity and environmental impact of nanomaterials,[1] and their potential effects on global economics. These concerns have led to a debate among advocacy groups and governments on whether special regulation of nanotechnology is warranted. Implications Most applications are limited to the use of "first generation" passive nanomaterials which includes titanium dioxide in sunscreen, cosmetics and some food products; Carbon allotropes used to produce gecko tape; silver in food packaging, clothing, disinfectants and household appliances; zinc oxide in sunscreens and cosmetics, surface coatings, paints and outdoor furniture varnishes; and cerium oxide as a fuel catalyst.The Truth Behind the Nanotechnology Buzz. This published study (with a foreword by Mikhail Roco, Senior Advisor for Nanotechnology at the National Science Foundation) concludes that much of what is sold as “nanotechnology” is in fact a recasting of straightforward materials science, which is leading to a “nanotech industry built solely on selling nanotubes, nanowires, and the like” which will “end up with a few suppliers selling low margin products in huge volumes." Further applications which require actual manipulation or arrangement of nanoscale components await further research. Though technologies branded with the term 'nano' are sometimes little related to and fall far short of the most ambitious and transformative technological goals of the sort in molecular manufacturing proposals, the term still connotes such ideas. According to Berube, there may be a danger that a "nano bubble" will form, or is forming already, from the use of the term by scientists and entrepreneurs to garner funding, regardless of interest in the transformative possibilities of more ambitious and far-sighted work. Nano-membranes have been produced that are portable and easily- cleaned systems that purify, detoxify and desalinate water meaning that third-world countries could get clean water, solving many water related health issues. Health and environmental concerns Some of the recently developed nanoparticle products may have unintended consequences. Researchers have discovered that silver nanoparticles used in socks only to reduce foot odor are being released in the wash with possible negative consequences.[32] Silver nanoparticles, which are bacteriostatic, may then destroy beneficial bacteria which are important for breaking down organic matter in waste treatment [33] plants or farms. A study at the University of Rochester found that when rats breathed in nanoparticles, the particles settled in the brain and lungs, which led to significant increases in biomarkers for inflammation and stress [34] response.
  3. 3. A major study published more recently in Nature Nanotechnology suggests some forms of carbon nanotubes – a poster child for the “nanotechnology revolution” – could be as harmful as asbestos if inhaled in sufficient quantities. Anthony Seaton of the Institute of Occupational Medicine in Edinburgh, Scotland, who contributed to the article on carbon nanotubes said "We know that some of them probably have the potential to cause mesothelioma. So those sorts of materials need to be handled very carefully." [35]. In the absence of specific nano-regulation forthcoming from governments, Paull and Lyons (2008) have called for an exclusion of engineered nanoparticles from organic food.[36] A newspaper article reports that workers in a paint factory developed serious lung disease and nanoparticles were found in their lungs. Applications Medicine : Main article: NanomedicineThe biological and medical research communities have exploited the unique properties of nanomaterials for various applications (e.g., contrast agents for cell imaging and therapeutics for treating cancer). Terms such as biomedical nanotechnology, bionanotechnology, and nanomedicineare used to describe this hybrid field. Functionalities can be added to nanomaterials by interfacing them with biological molecules or structures. The size of nanomaterials is similar to that of most biological molecules and structures; therefore, nanomaterials can be useful for both in vivo and in vitro biomedical research and applications. Thus far, the integration of nanomaterials with biology has led to the development of diagnostic devices, contrast agents, analytical tools, physical therapy applications, and drug delivery vehicles. [edit]Diagnostics Nanotechnology-on-a-chip is one more dimension of lab-on-a-chip technology.Magnetic nanoparticles, bound to a suitable antibody, are used to label specific molecules, structures or microorganisms. Gold nanoparticles tagged with short segments of DNA can be used for detection of genetic sequence in a sample. Multicolor optical coding for biological assays has been achieved by embedding different- sized quantum dots into polymeric microbeads. Nanopore technology for analysis of nucleic acids converts strings of nucleotides directly into electronic signatures. [edit]Drug delivery The overall drug consumption and side-effects can be lowered significantly by depositing the active agent in the morbid region only and in no higher dose than needed. This highly selective approach reduces costs and human suffering. An example can be found in dendrimers and nanoporous materials. They could hold small drug molecules transporting them to the desired location. Another vision is based on small electromechanical systems; NEMS are being investigated for the active release of drugs. Some potentially important applications include cancer treatment with iron nanoparticles or gold shells. A targeted or personalized medicine reduces the drug consumption and treatment expenses resulting in an overall societal benefit by reducing the costs to the public health system. Nanotechnology is also opening up new opportunities in implantable delivery systems, which are often preferable to the use of injectable drugs, because the latter frequently display first-order kinetics (the blood concentration goes up rapidly, but drops exponentially over time). This rapid rise may cause difficulties with toxicity, and drug efficacy can diminish as the drug concentration falls below the targeted range. [edit]Tissue engineering Nanotechnology can help to reproduce or to repair damaged tissue. “Tissue engineering” makes use of artificially stimulated cell proliferation by using suitable nanomaterial-based scaffolds and growth factors. Tissue engineering might replace today’s conventional treatments like organ transplants or artificial implants. Advanced forms of tissue engineering may lead to life extension.
  4. 4. [edit]Chemistry and environment Chemical catalysis and filtration techniques are two prominent examples where nanotechnology already plays a role. The synthesis provides novel materials with tailored features and chemical properties: for example, nanoparticles with a distinct chemical surrounding (ligands), or specific optical properties. In this sense, chemistry is indeed a basic nanoscience. In a short-term perspective, chemistry will provide novel “nanomaterials” and in the long run, superior processes such as “self-assembly” will enable energy and time preserving strategies. In a sense, all chemical synthesis can be understood in terms of nanotechnology, because of its ability to manufacture certain molecules. Thus, chemistry forms a base for nanotechnology providing tailor-made molecules, polymers, etcetera, as well as clusters and nanoparticles. [edit]Catalysis Chemical catalysis benefits especially from nanoparticles, due to the extremely large surface to volume ratio. The application potential of nanoparticles in catalysis ranges from fuel cell to catalytic converters and photocatalytic devices. Catalysis is also important for the production of chemicals. [edit]Filtration Main article: Nanofiltration A strong influence of nanochemistry on waste-water treatment, air purification and energy storage devices is to be expected. Mechanical or chemical methods can be used for effective filtration techniques. One class of filtration techniques is based on the use of membranes with suitable hole sizes, whereby the liquid is pressed through the membrane. Nanoporous membranes are suitable for a mechanical filtration with extremely small pores smaller than 10 nm (“nanofiltration”) and may be composed of nanotubes. Nanofiltration is mainly used for the removal of ions or the separation of different fluids. On a larger scale, the membrane filtration technique is named ultrafiltration, which works down to between 10 and 100 nm. One important field of application for ultrafiltration is medical purposes as can be found in renal dialysis. Magnetic nanoparticles offer an effective and reliable method to remove heavy metal contaminants from waste water by making use of magnetic separation techniques. Using nanoscale particles increases the efficiency to absorb the contaminants and is comparatively inexpensive compared to traditional precipitation and filtration methods. Some water-treatment devices incorporating nanotechnology are already on the market, with more in development. Low-cost nanostructured separation membranes methods have been shown to be effective in producing potable water in a recent study.[5] [edit]Energy Main article: Energy applications of nanotechnology The most advanced nanotechnology projects related to energy are: storage, conversion, manufacturing improvements by reducing materials and process rates, energy saving (by better thermal insulation for example), and enhanced renewable energy sources. [edit]Reduction of energy consumption A reduction of energy consumption can be reached by better insulation systems, by the use of more efficient lighting or combustion systems, and by use of lighter and stronger materials in the transportation sector. Currently used light bulbs only convert approximately 5% of the electrical energy into light. Nanotechnological approaches like light-emitting diodes (LEDs) or quantum caged atoms (QCAs) could lead to a strong reduction of energy consumption for illumination. [edit]Increasing the efficiency of energy production Today's best solar cells have layers of several different semiconductors stacked together to absorb light at different energies but they still only manage to use 40 percent of the Sun's energy. Commercially available solar cells have much lower efficiencies (15-20%). Nanotechnology could help increase the efficiency of light conversion by using nanostructures with a continuum of bandgaps.
  5. 5. The degree of efficiency of the internal combustion engine is about 30-40% at the moment. Nanotechnology could improve combustion by designing specific catalysts with maximized surface area. In 2005, scientists at the University of Toronto developed a spray-on nanoparticle substance that, when applied to a surface, instantly transforms it into a solar collector.[1] [edit]The use of more environmentally friendly energy systems An example for an environmentally friendly form of energy is the use of fuel cells powered by hydrogen, which is ideally produced by renewable energies. Probably the most prominent nanostructured material in fuel cells is the catalyst consisting of carbon supported noble metal particles with diameters of 1-5 nm. Suitable materials for hydrogen storage contain a large number of small nanosized pores. Therefore many nanostructured materials like nanotubes, zeolites or alanates are under investigation. Nanotechnology can contribute to the further reduction of combustion engine pollutants by nanoporous filters, which can clean the exhaust mechanically, by catalytic converters based on nanoscale noble metal particles or by catalytic coatings on cylinder walls and catalytic nanoparticles as additive for fuels. [edit]Recycling of batteries Main article: Nanobatteries Because of the relatively low energy density of batteries the operating time is limited and a replacement or recharging is needed. The huge number of spent batteries and accumulators represent a disposal problem. The use of batteries with higher energy content or the use of rechargeable batteries or supercapacitors with higher rate of recharging using nanomaterials could be helpful for the battery disposal problem. [edit]Information and communication Current high-technology production processes are based on traditional top down strategies, where nanotechnology has already been introduced silently. The critical length scale of integrated circuits is already at the nanoscale (50 nm and below) regarding the gate length of transistors inCPUs or DRAM devices. [edit]Memory Storage Electronic memory designs in the past have largely relied on the formation of transistors. However, research into crossbar switch based electronics have offered an alternative using reconfigurable interconnections between vertical and horizontal wiring arrays to create ultra high density memories. Two leaders in this area are Nantero which has developed a carbon nanotube based crossbar memory called Nano-RAM andHewlett-Packard which has proposed the use of memristor material as a future replacement of Flash memory. [edit]Aerospace Lighter and stronger materials will be of immense use to aircraft manufacturers, leading to increased performance. Spacecraft will also benefit, where weight is a major factor. Nanotechnology would help to reduce the size of equipment and thereby decrease fuel-consumption required to get it airborne. Hang gliders halve their weight while increasing their strength and toughness through the use of nanotech materials. Nanotech is lowering the mass of supercapacitors that will increasingly be used to give power to assistive electrical motors for launching hang gliders off flatland to thermal-chasing altitudes. [edit]Construction Nanotechnology has the potential to make construction faster, cheaper, safer, and more varied. Automation of nanotechnology construction can allow for the creation of structures from advanced homes to massive skyscrapers much more quickly and at much lower cost. [edit]Refineries Using nanotech applications, refineries producing materials such as steel and aluminium will be able to remove any impurities in the materials they create. [edit]Vehicle manufacturers
  6. 6. Much like aerospace, lighter and stronger materials will be useful for creating vehicles that are both faster and safer. Combustion engines will also benefit from parts that are more hard-wearing and more heat- resistant. [edit]Consumer goods Nanotechnology is already impacting the field of consumer goods, providing products with novel functions ranging from easy-to-clean to scratch-resistant. Modern textiles are wrinkle-resistant and stain-repellent; in the mid-term clothes will become “smart”, through embedded “wearable electronics”. Already in use are different nanoparticle improved products. Especially in the field of cosmetics, such novel products have a promising potential. [edit]Foods Complex set of engineering and scientific challenges in the food and bioprocessing industry for manufacturing high quality and safe food through efficient and sustainable means can be solved through nanotechnology. Bacteria identification and food quality monitoring using biosensors; intelligent, active, and smart food packaging systems; nanoencapsulation of bioactive food compounds are few examples of [7] emerging applications of nanotechnology for the food industry . Nanotechnology can be applied in the production, processing, safety and packaging of food. A nanocomposite coating process could improve food packaging by placing anti-microbial agents directly on the surface of the coated film.Nanocomposites could increase or decrease gas permeability of different fillers as is needed for different products. They can also improve the mechanical and heat-resistance properties and lower the oxygen transmission rate. [edit]Nano-foods New consumer products Emerging Nanotechnologies (PEN), based on an inventory it has drawn up of 609 known or claimed nano-products. On PEN's list are three foods -- a brand of canola cooking oil called Canola Active Oil, a tea called Nanotea and a chocolate diet shake called Nanoceuticals Slim Shake Chocolate. According to company information posted on PEN's Web site, the canola oil, by Shemen Industries of Israel, contains an additive called "nanodrops" designed to carry vitamins, minerals and phytochemicals through the digestive system. The shake, according to U.S. manufacturer RBC Life Sciences Inc., uses cocoa infused "NanoClusters" to enhance the taste and health benefits of cocoa without the need for extra sugar.[8] [edit]Household The most prominent application of nanotechnology in the household is self-cleaning or “easy-to-clean” surfaces on ceramics or glasses. Nanoceramic particles have improved the smoothness and heat resistance of common household equipment such as the flat iron. [edit]Optics The first sunglasses using protective and anti-reflective ultrathin polymer coatings are on the market. For optics, nanotechnology also offers scratch resistant surface coatings based on nanocomposites. Nano- optics could allow for an increase in precision of pupil repair and other types of laser eye surgery. [edit]Textiles The use of engineered nanofibers already makes clothes water- and stain-repellent or wrinkle-free. Textiles with a nanotechnological finish can be washed less frequently and at lower temperatures. Nanotechnology has been used to integrate tiny carbon particles membrane and guarantee full-surface protection from electrostatic charges for the wearer. Many other applications have been developed by research institutions such as the Textiles Nanotechnology Laboratory at Cornell University [edit]Cosmetics One field of application is in sunscreens. The traditional chemical UV protection approach suffers from its poor long-term stability. A sunscreen based on mineral nanoparticles such as titanium dioxide offer
  7. 7. several advantages. Titanium oxide nanoparticles have a comparable UV protection property as the bulk material, but lose the cosmetically undesirable whitening as the particle size is decreased. [edit]Agriculture Applications of nanotechnology have the potential to change the entire agriculture sector and food industry chain from production to conservation, processing, packaging, transportation, and even waste treatment. Strategic applications of Nano Science can do wonders in the agriculture scenario. NanoScience concepts and Nanotechnology applications have the potential to redesign the production cycle, restructure the processing and conservation processes and redefine the food habits of the people. Major Challenges related to agriculture like Low productivity in cultivable areas, Large uncultivable areas,Shrinkage of cultivable lands, Wastage of inputs like water, fertilisers, pesticides, Wastage of products and of course Food security for growing numbers can be addressed through various applications of nanotechnology. More details at [9] ````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````` The next few paragraphs provide a brief introduction to the core concepts of molecular nanotechnology, followed by links to further reading. Manufactured products are made from atoms. The properties of those products depend on how those atoms are arranged. If we rearrange the atoms in coal we can make diamond. If we rearrange the atoms in sand (and add a few other trace elements) we can make computer chips. If we rearrange the atoms in dirt, water and air we can make potatoes. Todays manufacturing methods are very crude at the molecular level. Casting, grinding, milling and even lithography move atoms in great thundering statistical herds. It's like trying to make things out of LEGO blocks with boxing gloves on your hands. Yes, you can push the LEGO blocks into great heaps and pile them up, but you can't really snap them together the way you'd like. In the future, nanotechnology will let us take off the boxing gloves. We'll be able to snap together the fundamental building blocks of nature easily, inexpensively and in most of the ways permitted by the laws of physics. This will be essential if we are to continue the revolution in computer hardware beyond about the next decade, and will also let us fabricate an entire new generation of products that are cleaner, stronger, lighter, and more precise.
  8. 8. It's worth pointing out that the word "nanotechnology" has become very popular and is used to describe many types of research where the characteristic dimensions are less than about 1,000 nanometers. For example, continued improvements in lithography have resulted in line widths that are less than one micron: this work is often called "nanotechnology." Sub-micron lithography is clearly very valuable (ask anyone who uses a computer!) but it is equally clear that conventional lithography will not let us build semiconductor devices in which individual dopant atoms are located at specific lattice sites. Many of the exponentially improving trends in computer hardware capability have remained steady for the last 50 years. There is fairly widespread belief that these trends are likely to continue for at least another several years, but then conventional lithography starts to reach its limits. If we are to continue these trends we will have to develop a new manufacturing technology which will let us inexpensively build computer systems with mole quantities of logic elements that are molecular in both size and precision and are interconnected in complex and highly idiosyncratic patterns. Nanotechnology will let us do this. When it's unclear from the context whether we're using the specific definition of "nanotechnology" (given here) or the broader and more inclusive definition (often used in the literature), we'll use the terms "molecular nanotechnology" or "molecular manufacturing." Whatever we call it, it should let us  Get essentially every atom in the right place.  Make almost any structure consistent with the laws of physics that we can specify in molecular detail.  Have manufacturing costs not greatly exceeding the cost of the required raw materials and energy. There are two more concepts commonly associated with nanotechnology:Positional assembly. Massive parallelism. Clearly, we would be happy with any method that simultaneously achieved the first three objectives. However, this seems difficult without using some form of positional assembly (to get the right molecular parts in the right places) and some form of massive parallelism (to keep the costs down). The need for positional assembly implies an interest in molecular robotics, e.g., robotic devices that are molecular both in their size and precision. These molecular scale positional devices are likely to resemble very small versions of their everyday macroscopic counterparts. Positional assembly is frequently used in normal macroscopic manufacturing today, and provides tremendous advantages. Imagine trying to build a bicycle with both hands tied behind your back! The idea of manipulating and positioning individual atoms and molecules is still new and takes some getting used to. However, as Feynman said in a classic talk in 1959: "The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom." We need to apply at the molecular scale the concept that has demonstrated its
  9. 9. effectiveness at the macroscopic scale: making parts go where we want by putting them where we want! One robotic arm assembling molecular parts is going to take a long time to assemble anything large — so we need lots of robotic arms: this is what we mean by massive parallelism. While earlier proposals achieved massive parallelism through self replication, today's "best guess" is that future molecular manufacturing systems will use some form of convergent assembly. In this process vast numbers of small parts are assembled by vast numbers of small robotic arms into larger parts, those larger parts are assembled by larger robotic arms into still larger parts, and so forth. If the size of the parts doubles at each iteration, we can go from one nanometer parts (a few atoms in size) to one meter parts (almost as big as a person) in only 30 steps Nanotechnology- its functions, benefits and dangers Nanotechnology Def: Functions Benefits Dangers Rh@saser
  10. 10. Electromagnetic Spectrum Measuring the electromagnetic spectrum You actually know more about it than you may think! The electromagnetic (EM) spectrum is just a name that scientists give a bunch of types of radiation when they want to talk about them as a group. Radiation is energy that travels and spreads out as it goes-- visible light that comes from a lamp in your house and radio waves that come from a radio station are two types of electromagnetic radiation. Other examples of EM radiation are microwaves, infrared and ultraviolet light, X-rays and gamma-rays. Hotter, more energetic objects and events create higher energy radiation than cool objects. Only extremely hot objects or particles moving at very high velocities can create high-energy radiation like X-rays and gamma-rays. Here are the different types of radiation in the EM spectrum, in order from lowest energy to highest: Radio: Yes, this is the same kind of energy that radio stations emit into the air for your boom box to capture and turn into your favorite Mozart, Madonna, or Justin Timberlake tunes. But radio waves are also emitted by other things ... such as stars and gases in space. You may not be able to dance to what these objects emit, but you can use it to learn what they are made of. Microwaves: They will cook your popcorn in just a few minutes! Microwaves in space are used by astronomers to learn about the structure of nearby galaxies, and our own Milky Way! Infrared: Our skin emits infrared light, which is why we can be seen in the dark by someone using night vision goggles. In space, IR light maps the dust between stars. Visible: Yes, this is the part that our eyes see. Visible radiation is emitted by everything from fireflies to light bulbs to stars ... also by fast-moving particles hitting other particles. Ultraviolet: We know that the Sun is a source of ultraviolet (or UV) radiation, because it is the UV rays that cause our skin to burn! Stars and other "hot"
  11. 11. objects in space emit UV radiation. X-rays: Your doctor uses them to look at your bones and your dentist to look at your teeth. Hot gases in the Universe also emit X-rays . Gamma-rays: Radioactive materials (some natural and others made by man in things like nuclear power plants) can emit gamma-rays. Big particle accelerators that scientists use to help them understand what matter is made of can sometimes generate gamma-rays. But the biggest gamma-ray generator of all is the Universe! It makes gamma radiation in all kinds of ways. A Radio Wave is not a Gamma-Ray, a Microwave is not an X-ray ... or is it? We may think that radio waves are completely different physical objects or events than gamma- rays. They are produced in very different ways, and we detect them in different ways. But are they really different things? The answer is 'no'. Radio waves, visible light, X-rays, and all the other parts of the electromagnetic spectrum are fundamentally the same thing. They are all electromagnetic radiation. Radio waves, visible light, X-rays, and all the other parts of the electromagnetic spectrum are fundamentally the same thing, electromagnetic radiation. Electromagnetic radiation can be described in terms of a stream of photons, which are massless particles each traveling in a wave-like pattern and moving at the speed of light. Each photon contains a certain amount (or bundle) of energy, and all electromagnetic radiation consists of these photons. The only difference between the various types of electromagnetic radiation is the amount of energy found in the photons. Radio waves have photons with low energies, microwaves have a little more energy than radio waves, infrared has still more, then visible, ultraviolet, X-rays, and ... the most energetic of all ... gamma-rays.
  12. 12. Actually, the electromagnetic spectrum can be expressed in terms of energy, wavelength, or frequency. Each way of thinking about the EM spectrum is related to the others in a precise mathematical way. So why do we have three ways of describing things, each with a different set of physical units? After all, frequency is measured in cycles per second (which is called a Hertz), wavelength is measured in meters, and energy is measured in electron volts. The electromagnetic spectrum can be expressed in terms of energy, wavelength, or frequency. The answer is that scientists don't like to use big numbers when they don't have to. It is much easier to say or write "two kilometers or 2 km" than "two thousand meters or 2,000 m". So generally, scientists use whatever units are easiest for whatever they are working with. In radio astronomy, astronomers tend to use wavelengths or frequencies. This is because most of the radio part of the EM spectrum falls in the range from about 1 cm to 1 km (30 gigahertz (GHz) to 100 kilohertz (kHz)). The radio is a very broad part of the EM spectrum. Infrared astronomers also use wavelength to describe their part of the EM spectrum. They tend to use microns (or millionths of meters) for wavelengths, so that they can say their part of the EM spectrum falls in the range 1 to 100 microns. Optical astronomers use wavelengths as well. Scientists use both angstroms (0.00000001 cm, or 10 -8 cm in scientific notation) and nanometers (0.0000001, or 10- 7 , cm). In the newer "SI" version of the metric system, we think of visible light in units of nanometers or 0.000000001 meters (10-9 m). In this system, the violet, blue, green, yellow, orange, and red light we know so well has wavelengths between 400 and 700 nanometers. This range is only a small part of the entire EM spectrum, so you can tell that the light we see is just a little fraction of all the EM radiation around us! By the time you get to the ultraviolet, X-ray, and gamma-ray regions of the EM spectrum, lengths have become too tiny to think about any more. So scientists usually refer to these photons by their energies, which are measured in electron volts. Ultraviolet radiation falls in the range from a few electron volts (eV) to about 100 eV. X- ray photons have energies in the range 100 eV to 100,000 eV (or 100 keV). Gamma-rays then are all the photons with energies greater than 100 keV. Question : Complete the table on the different types of electromagnetic waves and their uses.
  13. 13. GRAPHIC ORGANIZER A) Helicopters have both advantages and disadvantages compared to fixed-wing aircraft. The helicopter’s ability to manoeuvre in and out of hard-to-reach areas and to hover efficiently for long periods of time makes it valuable for operating in places where airplanes cannot land. Helicopters can perform important military tasks such as ferrying troops directly into combat areas or quickly transporting wounded soldiers to hospitals. However, helicopters use more fuel than airplanes and cannot fly as fast. This is because the helicopter rotor must produce both lift, which raises the craft into the sky, and thrust, which enables it to move about. In an airplane, the wings create lift and the engine produces thrust. Despite its poor cruising performance, the helicopter is the obvious choice for tasks where vertical flight is necessary. Helicopters Advantages 7………………………………. Ability to manoeuvre in and out of 1……………………………………………………………….. Uses 8………………………………………….. . Ability to hover 2……………………………………. Cannot fly 9……………………………………… for long periods of time ……………………………………………………….. Ability to 3. …………………………………………. Poor 10. ………………………………………… ………………………………where airplanes cannot land. Ability to perform military tasks. 4………………………………………………………………………………………....... 5…………………………………………………………………………………………….. Ability to do 6. …………………………………. …………………………………………………………
  14. 14. MCQ; Before mechanical refrigeration systems were introduced, people cooled their food with ice and snow, either found locally or brought down from the mountains. The first cellars were holes dug into the ground and lined with wood or straw and packed with snow and ice: this was the only means of refrigeration for most of history. Refrigeration is the process of removing heat from an enclosed space, or from a substance, to lower its temperature. A refrigerator uses the evaporation of a liquid to absorb heat. The liquid, or refrigerant, used in a refrigerator evaporates at an extremely low temperature, creating freezing temperatures inside the refrigerator. 1. The invention of refrigeration works along the idea of A. the need to keep food fresh B. The natural resources of ice and snow C. The evaporation of a liquid that absorbs heat D. Keeping high temperatures in an enclosed area 2. Based on the text, which of the following statements is true? A. The first refrigeration system was created in a cellar. B. The freezing liquid inside the refrigerator will be released. C. The refrigeration system releases heat when the inside is too hot. D. The materials used for the refrigeration system are only ice and snow. Rational cloze: Microwave ovens are popular because they cook food 1. ……………... They are also extremely 2………………… their use of electricity because a microwave oven heats only the food. A microwave oven uses microwaves to heat 3. ………………. food. Microwaves are radio waves. The commonly used radio wave frequency is 4…………………………….. 2,500 megahertz (2.5 gigahertz). Radio waves in this frequency 5…………… have an interesting property: they are absorbed by water, fats and sugars. Once absorbed, they are 6………………. directly into atomic motion – heat. Microwaves in this frequency range are not 7……………………… by most plastics, glass or ceramic. Metal 8………………………microwaves, which is why metal pans do not work well in a microwave oven. 1. A. well B. fully C. easily D. quickly 2. A. good B. efficient C. adequate D. systematic 3. A. at B. on C. up D. of 4. A. roughly B. generally C. naturally D. supposedly 5. A. group B. level C. value D. range 6. A. changed B. converted C. transformed D. interchanged 7. A. accepted B absorbed C. compatible D. transformed 8. A. produces B generates C. reflects D. absorbed
  15. 15. Answers; Graphic organizer: 1. hard-to-reach areas 2. efficiently 3. operate in places 4. Ferrying troops/soldiers directly into combat areas 5. Transporting wounded soldiers to hospitals 6. vertical flight 7. Disadvantages 8. more fuel 9. as fast as airplanes 10. cruising performance MCQ, 1. C 2. A Cloze text 1. D 2. B 3. C 4. A 5. D 6. B 7. B 8. C Importance of ICT 2. 1. * e-learning 3. * distance-learning 4. * lectures using teleconferencing services by lecturers from overseas 5. 2. *using ICT, doctors from different countries can exchange opinions on the diagnosis and treatment 6. of diseases. 7. 3. * monitors human activities on natural resource extractions to ensure the sustainability of the 8. natural resources 9. * helps battle against pollution through early detection of oil spillage 10. * detects climate changes and imminent disasters 11. 4. * satellites can show how crops are growing 12. *plant diseases can be detected in photographs taken from space 13. *farmers can access the web to learn how to protect their crops an dimprove crop yields 14. *fishermen can check the weather forecast and the condition of the sea from the Internet, they no 15. longer have to fish in rough waters 16. *satellites also direct fishermen to the best fishing grounds 17. 5. * record, store and distribute world stock market prices and trading 18. * transaction via banks can be done on-line
  16. 16. The Importance Of ICT Advances in ICT have brought many benefits to mankind. Give examples of benefits brought by advances in ICT. Benefits Examples 1. More opportunities for education 2.Better health 3.Protecting and managing our environment 4.More efficient use of resources 5.Budsiness and banking system
  17. 17. 1. QUESTION: Satellites play a very important role in this era of science and technology. Hundreds of artificial satellites have been sent to orbit to do what they are designed to do.Study the information given below:  Earth Resources Satellites- pictures of earth’s surface- information  Meteorology Satellites- predict weather-save lives  Military satellites- defense-search and rescue mission  Navigation satellites- navigators stay on course  Communications satellites – connect places  Relay telephone calls  Relay messages  Send and receive television signals. Write a report based on the information above. Your report must include the following; *function of satellites *benefits of satellites any other relevant information. ______________________________________________________________________________ Artificial Satellites As we move into the new era of globalization, the world starts changing and now gadgets A of modernization begin to escalate in production numbers and usage. Many of these A technologies are however connected to each other in order to work at optimum level. A One of the Earth’s most powerful and needed instrument of technology are the orbiting and floating objects in space called satellites. A One of the satellites that we use daily is the Earth Resources Satellites. This type of satellites is placed in the outer space and is used to take pictures of the earth’s surface. It is very useful when concerning agriculture as it provides information regarding the E1 P1 earth’s geology which is crucial in finding suitable places for farming. Besides that, it is E1E1 also used to study rocks and minerals available on earth. This, in turn helps in increasing E1 economic growth of a country through the discovery of natural resources and farmland. E1E1 Another useful and widely used satellites are the Meteorology satellites or the Weather Monitoring satellites. As the name goes, this type of satellites predicts the E2 weather and many of them are placed in space to fulfill the task. They help the weather forecasters in their weather prediction, and whether a thunderstorm or a typhoon is E2 E2 approaching. This helps to save lives by informing in advance of incoming weather P2E2 hazards like floods and tsunamis that might besiege the place. E2 Military satellites assist in the country’s defense system. They can detect an incoming foreign objects or entry of intruders via air, land or sea. This is vital in protecting the E3E3 country from potential enemies and at the same time, making preparations against E3 sudden enemy attacks. This helps in keeping the country safe and ensuring no entrance E3 of intruders that might harm the country. Military satellites also help in search and E3 rescue mission. Twenty four of these satellites are needed to form the Global Positioning P3E3 System (GPS) that indicates the location of a particular missing troop or person, hence E3 assisting in the search and rescue mission.
  18. 18. Navigation satellites on the other hand, ensure the navigators stay on course. Ships P4 and aeroplanes are given navigation from these satellites to help them reach their E4 destination. Navigation satellites are also used nowadays by the navigation system in cars where it helps to seek alternative roads in times of need like during emergencies or E4 E4 traffic jams. In addition, these satellites also help in informing incoming dangers or E4 turbulence in the sea or sky and at the same time giving directions to alternative routes. E4 Communication satellites connect places as they relay messages and telephone calls. P5P7P6 With the help of these satellites, communications can occur from varying places, near or E5 far. One could be in Japan and make a phone call back to Malaysia or even as far as the E5 E6 North Pole. With the help of communication satellites telephones now are wireless and E6 mobile. Satellites provide wide coverage, even to the remote areas. One can make a E6E5 phone call when deep inside a jungle or anywhere in the world. Communication satellites E6 have improved their vitality and usage as years passed and nowadays we could even E5 send video images through cell phones and with the mechanism of 3G we could E7 communicate in various ways. Messages relayed via telephone also are delivered much E7 faster compared to sending via snail mail. This is very convenient in emergency cases E7 such as when death happens in a family. These satellites also help to send and receive E7 television signals. It is via these satellites that we are able to watch live telecast of P8 football matches and all other live events on television right in your living room. This E8 definitely saves time and money as you do not have to go to the place where the event E8 or competition is held. E8 Satellites may be categorized according to their orbits. The higher the orbit of a A satellite, the longer the period taken for one orbit. The Low Earth orbits are placed at an AA altitude of 400 kilometres. On the other hand, the Geostationary satellites have high AA orbits and are positioned at a height of 36 000 kilometres above the Earth’s equator and A take exactly one day to complete an orbit. A The existence of satellites has benefited us a lot. Besides ensuring our safety they also keep us in track of everything around us and improve the system of communication. A Malaysia too has launched three satellites of its own and they are MEASAT 1 and A MEASAT 2 in 1996 and MEASAT 3 was launched in 2006. Even though launching of A satellites demands large capital their existence is much needed as they play vital role in A many aspects. Reported by, DR RAMLI BIN HUSIN
  19. 19. QUESTION : Methods Of Waste Disposal Landfills ( L ) Incineration ( I ) Reduction Campaign (R) Description *Bury waste in a hole * burning of waste * campaign- reduce, reuse, Recycle P1* restore mining * clean * reduce waste, Advantages grounds, quarries * quick solution resources P2* good management and * education- ways to control - successful reduce waste Disadvantages :* poor management * expensive * a long term plan * contaminate water * waste of resources * not all materials resources can be reused or recycled Write a report and include the following:  a waste management method of your choice  comparison of the three methods  reasons for choosing the method  any other relevant information.
  20. 20. Landfills Incinerators SYSAV incineration plant in Malmö, Sweden capable of handling 25 metric tons (28 short tons) per hour household waste. To the left of the main stack, a new identical oven line is under construction (March 2007). Incineration is a waste treatment technology that involves the combustion of organic materials and/or substances.[1] Incineration and other high temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into incinerator bottom ash, flue gases, particulates, and heat, which can in turn be used to generate electric power. The flue gases are cleaned of pollutants before they are dispersed in the atmosphere. Incineration with energy recovery is one of several waste-to-energy (WtE) technologies such as gasification, Plasma arc gasification, pyrolysis and anaerobic digestion. Incineration may also be implemented without energy and materials recovery. In several countries there are still expert and local community concerns about the environmental impact of incinerators (see The argument against incineration). In some countries, incinerators built just a few decades ago often did not include a materials separation to remove hazardous, bulky or recyclable materials before combustion. These facilities tended to risk the health of the plant workers and the local environment due to inadequate levels of gas cleaning and combustion process control. Most of these facilities did not generate electricity. Incinerators reduce the mass of the original waste by 80-85 % and the volume (already compressed somewhat in garbage trucks) by 95-96 %, depending upon composition and degree of recovery of materials such as metals from the ash for recycling.[2] This means that while incineration does not completely replace landfilling, it reduces the necessary volume for disposal significantly. Garbage trucks often reduce the volume of waste in a built-in compressor before delivery to the incinerator. Alternatively, at landfills, the volume of the uncompressed garbage can be reduced by approximately 70%[citation needed] with the use of a stationary steel compressor, albeit with a significant energy cost. In many countries simpler waste compaction is a common practice for compaction at landfills. Incineration has particularly strong benefits for the treatment of certain waste types in niche areas such as clinical wastes and certain hazardous wastes where pathogens and toxins can be destroyed by high temperatures. Examples include chemical multi-product plants with diverse toxic or very toxic wastewater streams, which cannot be routed to a conventional wastewater treatment plant. Waste combustion is particularly popular in countries such as Japan where land is a scarce resource. Denmark and Sweden have been leaders in using the energy generated from incineration for more than a century, in localised combined heat and power facilities supporting district heating schemes.[3] In 2005, waste incineration produced 4.8 % of the electricity
  21. 21. consumption and 13.7 % of the total domestic heat consumption in Denmark.[4] A number of other European Countries rely heavily on incineration for handling municipal waste, in particular Luxembourg, The Netherlands, Germany and France. [2] ALL LANDFILL LINERS AND LEACHATE COLLECTION SYSTEMS WILL FAIL ... "First, even the best liner and leachate collection system will ultimately fail due to natural deterioration, and recent improvements in MSWLF containment technologies suggest that releases may be delayed by many decades at some landfills. For this reason, the Agency is concerned that while corrective action may have already been triggered at many facilities, 30 years may be insufficient to detect releases at other landfills." Source: US EPA Federal Register, Aug 30, 1988, Vol.53, No.168, (scanned document). Check-out Peter Montegue's Rachel's for list of other comments in Federal Register by EPA. SUMMARY The U.S. has 3,091 active landfills and over 10,000 old municipal landfills, according to the Environmental Protection Agency. However, in the "good old days," every town (and many businesses and factories) had its own dump. According to the 1997 U.S. Census, there are 39,044 general purpose local governments in the United States - 3,043 county governments and 36,001 subcounty general purpose governments (towns & townships). One suspects that there are many more old and abandoned commercial, private, and municipal dumps than the 10,000 estimated by the EPA. Municipal landfills and their leachate (water) and air emissions are hazardous. Municipal landfills can accept hazardous waste under federal law. An unlimited number of 'conditionally exempt small generators' of hazardous waste have access to municipal landfills. (See 40 CFR 261.5). All landfills will eventually fail and leak leachate into ground and surface water. Plastics are not inert. State-of-the-art plastic (HDPE) landfill liners (1/10 inch or 100 mils thick) and plastic pipes allow chemicals and gases to pass through their membranes, become brittle, swell, and breakdown. "...82% of surveyed landfill cells had leaks while 41% had a leak area of more than 1 square feet," according to Leak Location Services, Inc. (LLSI) website (March 15, 2000). According to Dr. Fred Lee, "detection in new landfills can be difficult since the only way to know this is detection in the monitoring wells. The likelihood of a monitoring well at a single or double lined landfill detecting an initial leak is very small." Monitoring wells should be located in areas most likely to detect contamination (i.e., testing the ground water after it has passed under the landfill.) See: Subchapter I:
  22. 22. Solid Waste. Lined landfills leak in very narrow plumes, whereas old, unlined landfills will produce wide plumes of leachate. Old and new landfills are typically located next to large bodies of water (i.e., rivers, lakes, bays, etc), making leakage detection and remediation (clean-up) extremely difficult. This is due to the incursion of surface water in both instances. Federal and state governments have allowed landfill operators to locate landfills next to water bodies under the misguided principle: Detection by monitoring wells can also be very difficult at lined landfills. Lined landfills leak in very narrow plumes, whereas old, unlined landfills will produce wide plumes of leachate. Ground water flows downstream, or toward nearby lakes and rivers. In some cases, monitoring wells have been located around landfills in areas least likely to detect leakage (i.e., upstream of the groundwater flow). This is in violation of federal law. See Code of Federal Regulations (CFR): Chapter I - Environmental Protection Agency, Subchapter I: Solid Waste / PART 258 (Updated 1997) - Criteria for Municipal Solid Waste Landfills (Adobe PDF). If a landfill is located next to a water body, then the monitoring wells should be located between the landfill and the water; or (if there is no space left), in the water. See: EPA's Ground Water Monitoring All landfills could require remediation, but particularly landfills built in the last 60 years will require a thorough clean-up due to the disposal of highly toxic chemicals manufactured and sold since the 1940's. See:Remediation and Brownsfields
  23. 23. SAMPLE ANSWER To : The Director, Seremban City Council. From : Chief Engineer, Seremban City Council. Subject : Method Of Waste Disposal Based on the detailed findings of the three methods, I have chosen Reduction Campaign as the potential method of waste disposal. Reduction campaign is chosen mainly because of its advantages such as reducing wastage of resources. Depletion of natural resources will give rise to various environmental problems that can threaten our life. Hence, reduction campaigns which Choice encourage people to reuse, reduce and recycle must be taken seriously as this can reduce the negative effects to the environment. On the other hand, landfills where waste is buried in holes have the advantage of restoring mining grounds and quarries. In addition, with good management and control, this method can prove to be a success. Restoring mining grounds and quarries will ensure no wastage of land and balance of nature is not upset. Good management of waste includes dumping of waste according to the types of waste as well as proper management of leakage and methane gas which is the by- product of decomposition of waste. The construction of a landfill requires a well-planned approach and the primary concern is the location of the site. If the construction is not up to the predefined specifications added with poor management, landfills may lead to pollution of the local environment such as contamination of the water resources. Thus, it is vital that landfills are high above the groundwater table so as to avoid the leakage and contamination problem. Poor management of landfills may also give rise to accumulation of vectors in the area which can cause the spread of diseases. Therefore these adverse effects of landfill operations make it less desirable as a method of waste disposal. Another method of waste disposal is incineration. This method involves burning of waste at high temperature. This type of waste treatment is also described as thermal treatment. Even though this waste treatment method proves to be clean, the cost of its construction is too expensive making it too costly to set up. Building and operating incinerators involve a lot of money and require long recovery of investment capital. No doubt that it is a quick solution to waste treatment as it takes only a few hours compared to the other methods, but it is a complete wastage of resources as everything will be burnt where in actual fact, some can still be reused or recycled such as glass or plastic bottles. As the world’s population increases, there is more demand for basic needs and consequently more waste will be produced. This high amount of waste, if not properly managed, will upset the balance of nature and cause environmental problems like pollution and depletion of natural resources. Hence, reduction campaign should be carried out extensively as it is the responsibility of every individual to help manage the environment better. In the year 2000, the Ministry of Housing together with various local councils allocated RM 5 million to increase the awareness and
  24. 24. importance of recycling. About 2360 bins were distributed and placed at strategic places to collect the recyclable items. This has proven to be a success until today. Another effective way to reduce waste is through education which teaches the youngsters the right way to reduce waste. Schools for example can organize recycling campaigns where students are required to collect waste materials such as paper, aluminium cans, glass and plastics and send them to recycling centres to produce new aluminium cans, new glass bottles and plastic materials. They should also be encouraged to reuse old things such as old plastic bottles that can be turned into flower vases. Proper education should introduce school children to the many ways of reusing synthetic polymers which not biodegradable. These polymers if disposed anywhere or in open landfills without being processed, will remain in the environment for a long time and at the same time polluting the environment. Likewise, used tyres can be tied together and lowered into the sea bed to function as artificial reefs. These artificial reefs can act as a breeding ground for fish It is no doubt that not all materials can be reused or recycled and reduction campaigns need a long term plan to reach all levels of society especially in educating the public on the 3Rs as they are so used to throwing all unwanted items, but in my opinion this is still the best method as reduction campaigns help to conserve and preserve our natural environment. Of course certain wastes like food remnants and garden wastes cannot be recycled but this type of waste actually is of minimum amount. And some very harmful waste like cyanide can lead to death. This type cannot be recycled and need to be treated carefully at a special waste treatment plant such as ‘Pusat Kualiti Alam’ in Nilai, Negeri Sembilan. Thus, the obvious alternative to landfills and incineration method is reduction campaign. To reduce waste, we can use it to produce compost which is humus produced from the decomposition of organic substances such as domestic and garden wastes. The purpose of producing compost is to reduce the amount of garbage and to return useful minerals back into the soil. In recent years, some countries such as India and Netherlands have used animal dung to produced energy. Hence, based on the reasons stated, I strongly propose reduction campaign as the method of waste disposal. By; IR ELYAS B RAMLI, Chief Engineer, Seremban City Council. RH@SASER 2/2010