Nanotechnology

Answer the following questions:

1. The writer begins by saying that revolutionary nanotechlogy is still to develop. What kind of nanotechnology do we then have today?
A: - The writer begins the article by saying that revolutionary nanotechnology products, materials and applications such as Nano robotics etc. is still to develop. Nanotechnology products that we have today on the market are most gradually improved products, where some form of nanotechnology enabled material (e.g. Carbon nanotubes) or nanotechnology process (e.g. Nanopatterns or quantum dots for medical imaging) is used in the manufacturing process.

2. What are the two techniques that can be used to produce nanomaterials?
A: - Nanomaterials can be constructed by 'top-down' technique and 'bottom-up' technique.

             Top-down technique produces very small structures from large pieces of material for example by etching (cutting any material) to create circuits on the surface of a silicon microchip. Nanomaterials can also be constructed by bottom-up technique, atom by atom or molecule by molecule.

3. What are the two ways in which nanomaterials are presently being used?

A: - Currently there are two ways of using nanomaterials. They are: current applications and long term applications.

Sunscreens and cosmetics, composites, clay containing nanoparticles and tougher and harder cutting tools are considered (as) current applications. Long term applications are compatible in the next 5-15 years which can be applied in: magnetic materials, carbon nanotube composites, in medical implants, machinable ceramics, water purification, military suits, fibers and fabrics, in biomedical applications and air, water and gas filtration.

4. What properties of carbon nanotubes make them suitable for future applications and in which area?
A:- Carbonnanotube applications can be applied in Carbonnanotube composites, fibre and fabrics, carbonnanotube (CNT) ceramics, biomedical applications and the use of carbon nanotubes in composites like Carbon Black etc. are the important properties of carbon nanotubes that make them suitable for future applications.

5. How can nanotechnology be used to provide potable water, help soldiers on battlefields and patients needing surgery to repair or replace diseased organs?
A: - Nanoengineered membranes can potentially lead to more energy efficient water purification process, notably in desalination by reverse osmosis.

Enhanced nanomaterial can be used to prepare battle-suits for soldiers on battlefield. There is speculation that the short term development is likely to be energy absorbing materials that will hold blast waves. Long term are the ones that will include sensors to detect or respond to chemical and biological weapons. Though the current medical implants are biocompatible, in some cases they may wear out within the life time of the patient. While Nanocrystalline Zirconium Oxide is hard, wear-resistant and biocompatible for replacing diseased organs.

 

  

 

Solar Energy in Spain

 



Write brief answers to the following questions.

1. How does the opening paragraph of the passage show that its subject is related to the general theme of unit?
A: - The opening paragraph itself suggests the tremendous contribution of Spain country in the production of solar energy. It makes us clear that Spain has laid a platform for the development of solar energy.

        Spain is forging ahead with plans to build concentrating solar power plants with which they can establish their country and their companies as world leaders in the sphere of solar energy. The paragraph states that Spain has already installed numerous photovoltaic systems and researchers of Spain have also been continuously exploring new ways to improve solar power.

2. Although it seems far from that light are coming out of high tower in a Solucar solar plant and falling on tilted mirrors, what is the truth of the situation?
A: - In the structure of solar plant, in fact, the mirrors which are positioned in upturned manner, actually trace the sun and radiate its energy onto the high tower square sheet that is arranged on the top of the solar plant.

       While, when you travel from the road to the Solucar solar plant in the outskirts of Seville city, it seems to us that glowing white rays are coming out of the high tower and are falling on the mirrors. But it is not true as appearances are deceptive, in fact.

3. Why does Spain figure among the top countries in the world as well as Europe that are using solar power?

A: - The Spanish companies and researchers have been continually exploring new methods in solar energy production like Concentrating Solar Power (CSP), a type of solar thermal power. They have been installing number of photovoltaic systems, investing huge amount on them. Expanses of mirrors are also being assembled all around the country. Due to these measures and efforts, Spain has figured among the top countries in the world as well as in Europe in its use of solar power.

4. How does solar thermal power work differently from photovoltaic panels?
A: - During the production of solar energy, solar thermal power or Concentrating Solar Power (CSP) works differently from photovoltaic panels.

Unlike photovoltaic panels,  which control the movement of electrons between layers of a solar cell when the sun strikes the material, solar thermal power works by utilizing the heat of the sun. While concentrating solar power is very expensive. CSP has until recently cost nearly twice as much as traditional natural gas or coal power plants and it is effective only on a large scale.

 

5. What are the two kinds of technologies currently used to generate solar power on a large scale? Which one is use in the Solucar plant?
A: - The most common technologies that are currently used to generate solar power are Andasol 1 and the tower technology. Andasol 1 is based on a series of parabolic troughs i.e. huge curved mirrors about 18 feet wide that collects the sun’s energy and focuses it on a receiver pipe in the middle. Oil streams (flows) through that pipe along a long loop of troughs. The mirrors slowly   track the sun from east to west during day time hours and reach about 400° C. The heat transferred oil then travels to a steam generator, where the heat is transferred to water, immediately turning the water into stream. That steam powers a turbine.

      The tower technology works also on the same principle as the troughs- the sun's heat but uses curved mirrors called heliostats. The heliostats direct the sun's light to a central receiver at the top of the tower.

 

6. What provision has been made in the Solucar plant for rainy or cloudy weather?
A: - Besides huge size of mirrors, the Solucar plant is also supported by a small amount of natural gas, used when a stretch of rainy or overcast weather conditions, which prevent the plant's entire power production and the stored energy cannot stretch far enough to compensate.

 

 

Cloud Computing

Answer the following questions.

1. How can cloud computing be simply defined?
A: - Though there is no official definition and straightforward way to explain what exactly cloud computing is, it can be expressed in general as follows:
Cloud computing is a type of computing environment where business owners outsource their computing needs including application software services to a third party and when they need to use the computing power or if the employees need to use application resources such as data base or emails, they access them via the internet.

2. What are the advantages of using cloud computing?
A: - We can clearly comprehend the advantage of cloud computing with examples: imagine that you have a small business, where you need a few small servers for database, emails, applications etc. Servers need high computing power and are very expensive. If you depend on cloud computing, you need not to purchase servers, and thus eliminate the need for an operation and maintenance team. The main advantage of using cloud computing facility is that customers do not have to pay for infrastructure installation and maintenance cost. Hence, it is cost effective as doesn't require huge number of servers, doesn't require software updates, installation, email servers, anti-viruses, backups, web servers and both physical and logical security of our data. So, cloud computing can help us focus better on our core business competencies.

3. How do the three kinds of cloud environments available differ from one another?
A: - A cloud environment can be broadly categorized into three types- public cloud, private cloud and hybrid cloud. While these three kinds differ from one another.
-->Public Cloud: - This is the most popular type of cloud system and is considered a mainstream one by cloud computing experts. In this type, a third party data centre provides both disk space and computing power for all the application software. Amazon Web and Google Apps are two of the most popular public cloud computing service providers.
-->Private Cloud: - Unlike public cloud, in this type you need to set up your own data centre and also bear all the installation and maintenance expenses. Hence it is more expensive than public cloud. While, it provides more security and privacy and you will have complete control of all your data which doesn't provide public cloud.
-->Hybrid Cloud: - This is a composition of at least one private cloud and one public cloud. A hybrid cloud is typically offered in one of two ways- a vendor has a private cloud and forms a partnership with a public cloud provider, or a public cloud provider forms a partnership with a vendor who provides private cloud platforms.

4. What are the kinds of services offered by cloud service providers?
A: - A cloud service provider offers mainly three kinds of services.
-->Infrastructure as a service: -
The service provider bears all the costs of servers, networking equipment, storage and back-ups. The user just has to pay for the computing service. The users build their own application software. Amazon EC2 is a good example of this type of service.
-->Platform as a service:-
The service provider only provides the platform or a number of solutions for the users. It helps users save on investment on hardware and software. Google Gc engine and Force.com provide this type of service.
-->Software as a service:-
The service provider will give users the service of using their software, especially any type of applications software. Examples are Google, Salesforce.com and Net Suite.

5. What are the main problems with cloud computing technology as it is today?
A: - There are two major problems with cloud computing. They are: technical developments and security and privacy.
          In an era of outsourcing, all important data resides in a third party premises; there is, therefore, always a concern (or doubt) about the trustworthiness of the cloud service providers. Any security and privacy violation can be fatal. As a result, many business owners are still to be convinced about security and privacy in cloud computing systems. Data related to banking and government is particularly sensitive, confidential. Imagine what would happen if government documents were leaked or if information relating to credit cards fell into the hands of cyber criminals. Then it would be very problematic.

 

Water: The Elixir of Life

Write brief answers to the following questions:

1. What makes water one of the most powerful and wonderful thing on the earth?

A: - Humankind always searches in vain for an imaginary elixir of life, the divine Amrita, which is believed to give us eternal life. But the true elixir of life lies near our hands. It is nothing but the commonest of all liquids, the plain water! There is a lot of difference between the climatic and geographical area of the Libyan dessert (in which we find no signs of vegetation and living atmosphere) and the Valley of the Nile in Egypt in which we can notice the most fertile and densely populated areas. This remarkable difference is responsible only due to the water of the river Nile! Geologists also tell us that the entire soil of the Nile valley is the creation of the river itself. Egypt country, in fact was made by the Nile river water.

Water has been played a vital role in shaping the course of the earth's history and continues to play the leading role on earth. There is, In fact, nothing which adds so much to the beauty of the countryside as water. Hence it is apt to consider water as the most potent and wonderful thing on the face of our earth.

 

2. How does water help in the formation of fertile land?

A: - Fertile lands can be made with the help of water as it has power to carry silt in suspension. Swiftly flowing water can carry fairly large and heavy particles. The finest particles, however, remain floating within the liquid in spite of their greater density and are carried to great distances. In this manner, large areas of fertile land have been formed by the silt that was deposited. Such land, consisting of fine soil is very fertile for agriculture.

 

3. How does soil erosion happen and what are its main causes?

A:-the transformation of a large amount of silt, soil from any particular area is called soil erosion. Soil erosion is dangerous to agriculture. The problem of soil erosion is of major significance in various countries and especially in many parts of India. Soil erosion occurs in successive steps. The earliest of which may easily pass unnoticed. In the later stages, the cutting up and washing away of the earth is apparent results in the formation of deep gullies and ravines, which make all agriculture impossible. Excessively heavy rain in a large run of surplus water is the principal factor in causing soil erosion. The slop of the land, removal of the natural protective coat of vegetation, the existence of deep narrow marks made in the ground, and the absence of any checks of such flow are also causes of soil erosion.

 

4. What are some measures that are used to prevent soil erosion?

A: - As soil erosion is very harmful to agriculture, we need to take strict measures to prevent it. The terracing of the land, construction of bunds to check the flow of water, the practice of contour cultivation, in which ploughing and planting across the slope is made, and the planting of appropriate types of vegetation are the measures that can be used to check soil erosion. The systematic plantation of trees in every possible place is also an important measure to prevent soil erosion.

 

5. How, according to Sir C. V. Raman, can rainwater as well as the water of rivers be prevented from going to waste?

A: - It is true that much of Indian agriculture depends on seasonal rainfall. So the conservation of rainwater is of utmost important for us. In the countries like India, much of the rainwater flows down into the streams and the rivers and ultimately finds its way to the sea. Thus incredibly large quantities of the precious fluid are lost to the country.

          We need to harness our rivers and the waters of which now mostly run to waste. The systematic planting of suitable trees in every possible place is one of the most urgent needs of India. Such plantation would directly prove a source of untold wealth to the country. The trees would check soil erosion and conserve the rainfall of the country from flowing away to waste. Vast areas of land can be turned into fertile land by courageous and well-planned action.

6. Why does the writer say that the study of the nature and properties of water still has plenty of scope for scientific research?

A: - Water is the basis of all life. It's a naked fact that without having water the existence of life is impossible. The conservation and appropriate utilization of water is, thus, fundamental to human welfare. In one sense, water is the commonest of liquids. In another sense, it is the most uncommon of liquids with amazing properties which are responsible for its unique power of maintaining flora and fauna.

          As we have innumerous advantages of water, the investigation of nature and properties of water is of the highest scientific interest and is far from being an exhausted field of research.