ENGLISH FOR SCIENCE AND TECHNOLOGY
THEME: COMMUNICATION &
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.
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, 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.
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. Silver nanoparticles, which are bacteriostatic, may then
destroy beneficial bacteria which are important for breaking down organic matter in waste treatment
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
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." . 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. A newspaper article
reports that workers in a paint factory developed serious lung disease and nanoparticles were found in
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
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.
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.
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.
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
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.
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.
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.
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.
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.
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.
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.
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
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.
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.
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.
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.
Using nanotech applications, refineries producing materials such as steel and aluminium will be able to
remove any impurities in the materials they create.
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-
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
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
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.
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.
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.
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.
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
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
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.
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 http://www.sainsce.com/agriculture.aspx 
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
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.
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
Have manufacturing costs not greatly exceeding the cost of the required raw materials and
There are two more concepts commonly associated with nanotechnology:Positional assembly.
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
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
effectiveness at the macroscopic scale: making parts go where we want by putting them where
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
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
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
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
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"
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
Radio waves, visible light, X-rays, and all the
other parts of the electromagnetic spectrum are
fundamentally the same thing, electromagnetic
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.
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-
, 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.
Complete the table on the different types of electromagnetic waves and their uses.
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.
Ability to manoeuvre in and out of
Ability to hover 2……………………………………. Cannot fly 9………………………………………
for long periods of time ………………………………………………………..
Ability to 3. ………………………………………….
Poor 10. …………………………………………
Ability to perform military tasks.
Ability to do 6. ………………………………….
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.
Microwave ovens are popular because they cook food 1. ……………... They are also extremely
2…………………..in 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
1. hard-to-reach areas
3. operate in places
4. Ferrying troops/soldiers directly into combat areas
5. Transporting wounded soldiers to hospitals
6. vertical flight
8. more fuel
9. as fast as airplanes
10. cruising performance
1. C 2. A
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
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
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
The Importance Of ICT
Advances in ICT have brought many benefits to mankind. Give examples of benefits brought by advances
1. More opportunities for
3.Protecting and managing
4.More efficient use of
5.Budsiness and banking
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
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.
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.
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
DR RAMLI BIN HUSIN
QUESTION : Methods Of Waste Disposal
Landfills ( L ) Incineration ( I ) Reduction Campaign
Description *Bury waste in a hole * burning of waste * campaign- reduce,
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
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.
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. 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
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
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. 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% 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
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. In 2005, waste incineration produced 4.8 % of the electricity
consumption and 13.7 % of the total domestic heat consumption in Denmark. A number of
other European Countries rely heavily on incineration for handling municipal waste, in particular
Luxembourg, The Netherlands, Germany and France. 
ALL LANDFILL LINERS AND LEACHATE COLLECTION SYSTEMS WILL
"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.
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:
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
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
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
Hence, based on the reasons stated, I strongly propose reduction campaign as the method of
IR ELYAS B RAMLI,
Seremban City Council.