NANOMATERIALS

Reading Time: 10 minutes

INTRODUCTION

Nano means one billionth that means 10^-9 times in scientific notation. Have you ever thought how small it is? Avg human height is around 1.5-2m, size of ants are about 2mm, the diameter of a human hair is around 100mm and size of our DNA is around 2nm that means it is 10^-9 times smaller than average human height. To imagine how small is one-billionth let’s go on the other side and see how big an object would be if we are one billionth time larger than the humans. The diameter of the sun is about one billionth times larger than a human. That’s pretty big. So our DNA is as small as humans as humans are from the sun.

What are nanomaterials?? What is its importance? Where are they used? Let’s dive into the world of smallness!!!

Nanomaterials include a broad class of materials, which has at least one dimension less than 100nm. Depending on their shape, they can be 0-D, 1-D, 2-D or 3-D. You may be thinking what this small piece of material can do?? Nanomaterials have an extensive range of applications. The importance of these materials was realized when it was found that size can influence the physicochemical properties of a substance. Nanoparticles have biomedical, environmental, agricultural and industrial based applications.

Nanoparticles are composed of 3 layers-

  • The Surface Layer- It may be functionalized with a variety of small molecules, metal ions, surfactants and polymers.

  • The Shell Layer- It is a chemically different material from the core in all aspects.

  • The Core- It is the central portion of the nanoparticle and usually referred to as nanoparticle itself.

These materials got immense interest from researchers in multidisciplinary fields due to their exceptional characteristics.

CLASSIFICATION OF NANOPARTICLES

Based on the physical and chemical characteristics, some of the well-known classes of NPs are-

  1. CARBON-BASED NPs

  • FULLERENES- It contains nanomaterials that are made up of globular hollow cage such as allotropic forms of carbon. They have properties like electrical conductivity, high strength, structure, electron affinity and versatility. They possess pentagonal and hexagonal carbon units, while each carbon is sp2 hybridized. The structure of C-60 is called Buckminsterfullerene

  • CARBON NANOTUBES(CNTs)- They have elongated, tubular structure, 1-2nm in diameter. They structurally resemble graphite sheets rolling upon itself, which can have single double and many walls and therefore are named as single-walled (SWNTs), double-walled (DWNTs) and multi-walled carbon nanotubes (MWNTs) respectively. They are widely synthesized by decomposition of carbon, especially atomic carbons, vaporized from graphite by laser or by an electric arc to metal particles. Chemical Vapour Deposition (CVD) technique is also used to synthesize CNTs. They can be used as fillers, efficient gas absorbents and as a support medium for different inorganic and organic catalysts.

NANOMATERIALS

  1. METAL NPs

They are purely made up of metal precursors. Due to Localized Surface Plasmon Resonance (LSPR) characteristic, they possess unique optoelectrical properties. Due to excellent optical properties, they find their application in various research areas. For example, gold nanoparticles are used to coat the sample before analyzing in SEM.

  1. CERAMIC NPs

They are inorganic, nonmetallic solids, synthesized via heat and continuous cooling. They are made up of oxides, carbides, carbonates and phosphates. They can be found in amorphous, polycrystalline, dense, porous or hollow forms. They found their application in catalysis, photocatalysis, photodegradation of dyes and imaging application.

  1. SEMICONDUCTOR NPs

They possess wide band gaps and therefore show significant alteration in their properties with bandgap tuning. They are used in photocatalysis, photo optics and electronic devices. Some of the examples of semiconductor NPs are GaN, GaP, InP, InAs.

  1. POLYMERIC NPs

They are organic-based NPs, mostly nanospheres and nanocapsules in shape. They are readily functionalized and therefore have a wide range of applications.

  1. LIPID NPs

They contain liquid moieties and are effectively used in many biomedical applications. They are generally spheres with diameters ranging from 10 to 1000nm. They have a solid core made of lipid, and a matrix contains soluble lipophilic molecules.

SYNTHESIS OF NPs

There are various methods used for the synthesis of NPs, which are broadly classified into two main classes-

  1. TOP-DOWN APPROACH

Top-down routes are included in the typical solid-state processing of the materials. It is based on bulk materials and makes it smaller, thus using physical processes like crushing, milling and grinding to break large particles. It is a destructive approach, and it is not suitable for preparing uniformly shaped materials. The biggest drawback in this approach is the imperfections of the surface structure, which has a significant impact on physical properties and surface chemistry of nanoparticles. Examples of this approach include grinding/milling, CVD, PVD and other decomposition techniques.

NANOMATERIALS

  1. BOTTOM-UP APPROACH

As the name suggests, it refers to the build-up of materials from the bottom: atom by atom, molecule by molecule or cluster by cluster. They are more often used for preparing most of the nanoscale materials which have the ability to generate uniform size, shape and distribution. It effectively covers chemical synthesis and precisely controls the reaction to inhibit further particle growth. Examples are sedimentation and reduction techniques. It includes sol-gel, green synthesis, spinning and biochemical synthesis.

CHARACTERIZATION OF NPs

Analysis of different physicochemical properties of NPs is done using various characterization techniques. It includes techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Infrared (IR), SEM, TEM and particle size analysis.

  1. MORPHOLOGICAL CHARACTERIZATION

Morphology always influences most of the properties of the NPs. Microscopic techniques are used for characterization for morphological studies such as a polarized optical microscope, SEM and TEM.

SEM technique is based on electron scanning principle. It uses a focused beam of high energy electrons to generate a variety of signals at the surface of solid specimens. It is not only used to study the morphology of nanomaterials, but also the dispersion of NPs in the bulk or matrix.

TEM is based on electron transmission principle so that it can provide information on bulk material from very low to higher magnification. In TEM a high energy beam of electrons is shone through a skinny sample. This technique is used to study different morphologies of gold NPs. It also provides essential information about two or more layer materials.

NANOMATERIALS

  1. STRUCTURAL CHARACTERIZATION

Structural characteristics are of primary importance to study the composition and nature of bonding materials. It provides diverse information about the bulk properties of the subject material. XRD, Energy dispersive X-ray (EDX), XPS, IR, Raman and BET are the techniques used to study the structural properties of NPs.

XRD is one of the most used characterization techniques to disclose the structural properties of NPs. Crystallinity and phases of nanoparticles can be determined using this technique. Particle size can also be determined by using this technique. It worked well in identification of both single and multiphase NPs.

EDX is usually fixed with field emission-SEM or TEM device is widely used to know about the elemental composition with a rough idea of per cent weight. Nanoparticles comprise constituent elements, and each of them emits characteristic energy X-rays by electron beam eradication.

XPS is one of the most sensitive techniques used to determine the exact elemental ratio and exact bonding nature of elements in nanoparticles materials. It is a surface-sensitive technique used in-depth profiling studies to know the overall composition and the compositional variation with depth.

  1. PARTICLE SIZE AND SURFACE AREA CHARACTERIZATION

Size of the particle can be estimated by using SEM, TEM, XRD and dynamic light scattering (DLS). Zeta potential size analyzer/DLS can be used to find the size of NPs at a deficient level.

NTA is another new and exclusive technique which allows us to find the size distribution profile of NPs with a diameter ranging from 10 to 1000nm in a liquid medium. By using this technique, we can visualize and analyze the NPs in a liquid medium that relates the Brownian motion rate to particle size. It can be helpful in biological systems such as protein and DNA.

NPs have large surface areas, so it offers excellent room for various applications. BET is the most used technique to determine the surface area of nanoparticles material. Principle of this technique is adsorption and desorption and Brunauer-Emmett-Teller (BET) theorem.

  1. OPTICAL CHARACTERIZATION

Optical properties are of great concern in photocatalytic applications. These characterizations are based on Beer-lambert law and basic light principles. The techniques used to give information about absorption, luminescence and phosphorescence properties of NPs. The optical properties of NPs materials can be studied by well-known equipment like Ultraviolet-visible, photoluminescence and the ellipsometer.

PHYSICOCHEMICAL PROPERTIES OF NPs

So it’s all about the size, isn’t it? Yes and no. When a material becomes a nanomaterial is not so simple. A nanomaterial may have different properties compared to the same substance in bulk form. That means that a material could change when it goes from bulk to nanoform, but at what size that happens varies depending on the substance.Nanoparticles are used in various applications due to their unique properties such as large surface area, strength, optically active and chemically reactive.

  1. ELECTRONIC AND OPTICAL PROPERTIES

The optical and electronic properties of nanoparticles are dependent on each other. For example, gold colloidal nanoparticles are the reason for the rusty colours seen in blemished glass windows, while Ag NPs are typically yellow. The free electrons on the surface of nanomaterials are free to move across the material. The mean free path of Ag and gold is ~50nm, which is greater than the NPs size of these materials. Therefore, no scattering is expected from the bulk, when light interacts. Instead, they set into a standing resonance condition, which is responsible for LSPR in the NPs.

  1. MAGNETIC PROPERTIES

There is a class of nanoparticles known as magnetic nanoparticles that can be manipulated using magnetic fields. Such particles consist of two components- a magnetic material and chemical component that has functionality. These types of materials have a wide range of applications which includes heterogeneous and homogeneous catalysis, biomedicine, magnetic fluids, MRI and also in water decontamination. Magnetic properties of NPs dominate when its size is less than the critical value, i.e. 10-20nm. The reason for these magnetic properties is the uneven electronic distribution in NPs.

  1. MECHANICAL PROPERTIES

To know the exact mechanical nature of NPs different mechanical parameters such as elastic modulus, hardness, stress and strain, adhesion and friction are surveyed. Due to distant mechanical properties of NPs, it finds its application in fields like tribology, surface engineering, nanofabrication and nanomanufacturing. NPs shows different mechanical properties as compared to microparticles and their bulk materials.

  1. THERMAL PROPERTIES

It is well known that metals have better thermal conductivities than that of fluids. Same is the case of NPs. Thermal conductivity of copper is much higher than water and engine oil. Thermal conductivity of fluids can be increased by dispersing solid particles in them. Using the same way nanofluids are produced which have nanometric scales solid particles dispersed into a liquid such as water, ethylene glycol or oils. They are expected to exhibit superior properties relative to those of conventional heat transfer fluids and fluids containing microscopic solid particles. As heat transfer takes place at the surface of the particles, it is better to use the particles with large surface area, and it also increases the stability suspension.

APPLICATIONS

As discussed above the nanoparticles have various unique properties. Due to their properties, they find their applications in multiple fields, including drugs, medication, manufacturing, electronics, multiple industries and also in the environment.

NANOMATERIALS

Nano-sized inorganic particles have unique, physical and chemical properties. They are an essential material in the development of various nanodevices which can be used in multiple physical, biological, biomedical and pharmaceutical applications. Particles of an iron oxide such as magnetite (Fe3O4) or its oxides from maghemite (Fe2O3) are used in biomedical applications. Polyethene oxide (PEO) and polylactic acid (PLA) NPs have been revealed as up-and-coming systems for the intravenous administration of drugs. Biomedical applications require NPs with high magnetization value, a size smaller than 100nm and a narrow particle size distribution. Most of the semiconductor and metal NPs have immense potential cancer diagnosis and therapy.

Image shows the bamboo-like structure of nitrogen-doped carbon nanotubes for the treatment of cancer.

NANOMATERIALS

In specific applications within the medical, commercial and ecological sectors manufacturing NPs are used which show physicochemical characteristics that induce unique electrical, mechanical, optical and imaging properties. Nanotechnology is used in various industries, including food processing and packaging. The unique plasmon absorbance features of the noble metals NPs have been used for a wide variety of applications including chemical sensors and biosensors.

Nanomaterials are also used in some environmental applications like green chemistry, pollution prevention, the recommendation of contaminated materials and sensors for ecological stages.

NPs such as metallic NPs, organic electronic molecules, CNTs and ceramic NPs are expected to flow as a mass production process for new types of electronic equipment.

NPs can also offer applications in mechanical industries, especially in coating, lubricants and adhesive applications. Its mechanical strength can be used to produce mechanically more reliable nanodevices.

CONCLUSION

Nanomaterials are no doubt the future of technology, being the smallest material they have a wide range of applications due to their unique physical and chemical properties. Due to their small size, NPs have a large surface area which also makes them suitable candidates for many applications. Even at that size, optical properties dominate, which further increase their importance in photocatalytic applications. Though NPs are used for various applications, still they have some health hazard concerns due to their uncontrollable use and discharge to the natural environment, which should be considered to make the use of NPs more convenient and environmentally friendly.

WONDER, THINK, CREATE!!!

Keep Learning!, Keep Growing!

Team CEV

RADIOACTIVE FIRE: The Chernobyl Disaster

Reading Time: 8 minutesOn April 26, 1986, a sudden surge of power during a reactor systems test destroyed Unit 4 of the nuclear power station at Chernobyl, Ukraine, in the former Soviet Union.  A nuclear meltdown in one of the reactors caused a fire that sent a plume of radioactive fallout that eventually spread all over Europe. You know how dangerous radioactive materials involved in a fire can be and what they had done to Chernobyl. Let’s find out all these in detail.

RADIOACTIVE MATERIALS

Radioactive materials are any material which contains unstable atoms that emit ionizing radiations as it decays. Radioactive atoms have too much energy. When they spontaneously release their excess energy, they are said to decay. After releasing all their excess energy, the atoms become stable and are no longer radioactive. This radiation can be emitted in the form of positively charged alpha particles, negatively charged beta particles, gamma rays, or x-rays. Radiation is energy given off in the form of rays and high-speed particles.

Fires involving radioactive materials can result in widespread contamination. Radioactive particles can be carried easily by smoke plumes, ventilation systems. Fire in radioactive material is hazardous, and we know that Nuclear Power Plants contain lots of radioactive material. Fire in a Nuclear Power Plant is dangerous as it will result in the release of numerous radiations which is very dangerous for the environment. Most of the radiation released from the failed nuclear reactor is from fission products iodine-131, cesium-134, and cesium-137. Iodine-131 has a relatively short half-life of eight days, but is rapidly ingested through the air and tends to localize in the thyroid gland. Caesium isotopes have longer half-lives (cesium-137 has a half-life of 30 years) and are a concern for years after their release into the environment. Such incidents happened in this world, and the major one was the Chernobyl Nuclear Power Plant Incident. Let’s discover what happened there, and the steps taken.

THE INCIDENT

On April 26, 1986, the Chernobyl power plant located near the city of Pripyat in northern Ukraine became the site of the worst ever nuclear accident. A massive steam explosion destroyed the reactor hall of unit 4, and radioactive material was released, affecting large parts of Ukraine, Belarus and Russia, but also reaching western Europe. On the evening of April 25, 1986, a group of engineers, lacking knowledge in nuclear physics, planned an electrical-engineering experiment on reactor number 4. They thought of experimenting how long turbines would spin and supply power to the main circulating pumps following a loss of main electrical power supply.

CAUSE OF DISASTER

RADIOACTIVE FIRE: The Chernobyl DisasterRADIOACTIVE FIRE: The Chernobyl Disaster

Operators decided to conduct a safety test, which they have timed to coincide with a routine shutdown for maintenance. The test was to determine whether, in the event of power failure, the plant still-spinning turbines can produce enough electricity to keep coolant pumps running during the brief gap before the emergency generators kick in.

To conduct the test reactor number 4’s core cooling system was disabled to keep it from interacting with the test. The reactor had to be stabilized at about 700-1000 MW prior to shut down, but it fell to 5000 MW due to some operational phenomenon. Later the operator committed an error and caused the reactor to go into the near-shutdown state by inserting the reactor control rods, which resulted in the drop of power output to around 30 MW. This low power wasn’t adequate to make the test and will make the reactor unstable. They decided to extract the control rods to restore the power, which was the violation of safety rules due to the positive void co-efficiency of the reactor.  The positive void coefficient is the increasing number of reactivity in a reactor that changes into steam. Extraction of control rods made power to stabilize at 200 MW at which they carried out the test, but the reactors were highly unstable at the lower power level. Even though the engineers continued with the experiment and shut down the turbine engine to see if its inertial spinning would power the reactor’s water pumps, it did not adequately power the water pumps. Without the cooling water, the power level in the reactor surged.

The water pumps started pumping water at a slower rate and them together with the entry to the core of slightly warmer feed water, may have caused boiling (void formation) at the bottom of the core. The void formation, along with xenon burn out, might have increased the power level at the core. The power level was then increased to 530 MW and continued to rise. The fuel elements were ruptured and led to steam generation, which grew the positive void coefficient resulting in high power output.

The high power output alarmed the engineers who pressed the emergency shutdown button and tried to insert all the 200 control rods, which is a conventional procedure done to control the core temperature. But these rods got jammed half the way, because of their graphite tip design. So, before the control rods with their five-meter absorbent material could penetrate the core, 200 graphite tips simultaneously entered the core, which facilitated the reaction to increase.

This ended up in two explosions. The first explosion, to be quickly followed by at least one more, blows the 1,000-ton roof right off the reactor and shoots a fireball high into the night sky. A blackout roils the plant as the air fills with dust and graphite chunks, and radiation begins spewing out.

All the materials such as Fuel, Moderator and Structural materials got eject, starting several fires and the destroyed core got exposed to the atmosphere. In the explosion and ensuing fire, more than 50 tons of radioactive material got released into the atmosphere, where air currents carried it. The blast was 400 times the amount of radioactive materials released at the time of the Hiroshima bombing.

HOW FIRE WAS CONTROLLED??

The firefighters present didn’t have any clue about what they were handling. They believed that they were tackling an ordinary blaze and were wearing no protective clothing. They turned off Reactor 3  immediately followed by reactor 1 and 2. By the next morning, all the fire was extinguished except for a blaze in the reactor 4.

Soviet authorities spooked by the political fallout tried to cover up the scale of the disaster. They even denied any knowledge of the nuclear disaster after Sweden reported radioactive particles in its airspace.

After continuous pumping of radiations into the air, authorities realized that they had to stop.

The radiations coming out were getting dangerous and were needed to stop. Hence, they used Boron because of its property to absorb neutrons so it would effectively end the fire by neutralizing the uranium atoms shot about at random. With the help of helicopters, they dumped more than 5,000 metric tons of sand, clay and Boron onto the burning, exposed reactor no. 4.

The helicopters used to dump the load struggled as they were not allowed to fly directly above the open reactor.

RADIOACTIVE FIRE: The Chernobyl Disaster

While the fire got suppressed, the authorities came up with a more significant problem of a nuclear meltdown due to overheating.

Half of Europe was in the danger of getting wiped out as the core was melted and was reacting with the groundwater underneath the plant, this would have caused a second, bigger explosion.

Three volunteer divers were sent into the depths of the power plant to open valves that would drain the water To prevent the second explosion. In this way, the big bang got restricted.

But 400 miners also had to be brought in to dig underneath the power plant and install a cooling system as the groundwater was still contaminated.

The heroes completed their work, knowing they were being exposed to radiation poisoning, in just six weeks despite a three-month project projection.

The efforts of all involved saved millions of lives.

WHY BORON AND SAND?

Exposing a burning nuclear core to the air is a problem on at least two levels.

First was an ongoing nuclear fission reaction. Uranium fires off neutrons which are slamming into other atoms and splitting them, releasing more energy yet and feeding the whole hot mess. The second problem was the presence of an assortment of types of relatively lightweight elements that form when uranium atoms split in the fire coming right out of a nuclear reactor which was very dangerous for the human body.

The sand was to smother the exposed reactor, squelching that deadly smoke plume.

Boron is one of the few elements to possess nuclear properties, which warrant its consideration as neutron absorber material. Due to its atomic structure, it’s sort of neutron-thirsty. So the plan was to dump enough boron on the exposed reactor, and it would absorb so many of those wildly firing neutrons that the reaction would stop.

In Chernobyl’s case, however, dumping the boron and other neutron absorbers onto the reactor turned out not to work as helicopters were not allowed to fly directly above the open nuclear reactor.

WHY NOT WATER?

As the molten metal was present inside the reactor, it oxidises in contact with water, stripping oxygen from the water molecule and leaving free hydrogen. Hydrogen could mix with air and explode. That’s why divers were sent into the depth of the power plant to open valves which drains out the underground water.

WHAT WOULD WE DO TODAY?

The modern-day nuclear reactors are much less likely than Chernobyl to encounter any sort of disaster. They will never run as hot and operate in sturdier vessels. The buildings themselves are designed to do much of the work to squelch a nuclear reactor fire and a radioactive plume. Modern-day reactors are equipped with chemical sprays that can flood the reactor buildings and will take the isotopes out of the air before they can escape. Unlike the Chernobyl, nuclear facilities are entirely enclosed in sealed structures of cement and rebar. These structures are so strong that even the jet crash won’t affect them, and it wouldn’t expose the core.

Emergency handbooks are present for each nuclear power plant laying out information of what responders should do in the events of all sorts of somewhat- plausible to highly unlikely emergencies. As soon as the reactor fails to shut down normally, lots of boron is to be shovelled into the core.

RADIOACTIVE FIRE: The Chernobyl Disaster

CONCLUSION

The accident at the Chernobyl nuclear power plant in 1986 was a tragic event for its victims, and those most affected suffered significant hardship. The leading cause of the disaster was the technical flaws in the process of Steam Turbine Test and low safety measures taken during the test. Due to radiation emission from the reactor, several problems related to human beings and the environment. Dumping boron was a good idea, but they were not able to find a better way to drop it. Fighting a fire on an exposed uranium core will always come down to more or less fancy versions of dumping boron and sand.

REFERENCES

  1.  International Journals of Advanced Research in Computer Science and Software Engineering ISSN: 2277-128X (Volume-8, Issue-2)
  2. https://www.livescience.com/65515-chernobyl-in-modern-times-nuclear-emergency.html
  3.  Mikhail Balonov, Malcolm Crick and Didier Louvat, Update of Impacts of the Chernobyl Accident: Assessments of the Chernobyl Forum (2003-2005) and UNSCEAR (2005-2008)
  4. INSAG-7, The Chernobyl Accident: Updating of INSAG-1, A report by the International Nuclear Safety Advisory Group, International Atomic Energy Agency, Safety Series No. 75-INSAG-7, 1992, (ISBN: 9201046928)
  5. https://www.ebrd.com/what-we-do/sectors/nuclear-safety/chernobyl-overview.html
  6. http://www.unscear.org/unscear/en/chernobyl.html
  7. United Nations Scientific Committee on the Effects of Atomic Radiation – Chernobyl
  8. https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/chernobyl-bg.html
  9. https://www.livescience.com/39961-chernobyl.html
  10. https://inis.iaea.org/collection/NCLCollectionStore/_Public/12/627/12627520.pdf

FIRE: The Perception

Reading Time: 7 minutes“Fire breaks out in a building,” “Australia’s biggest forest fire ever rages.” We often hear about such devastative fire incidents in the media. We know that fire is dangerous and can cause severe damage and destruction and, at times, death. Since our earliest days, humans have sought to find out what fire is, how it starts, and what keeps it going.

Sometimes we might think that fire is a living thing! It moves, ‘eats’ things, and seems to breathe. The ancient Greeks thought it was one of four major elements, along with water, earth, and air. They could feel, see, and smell fire just like they could the earth, water, and air, but fire is something completely different.

Let us go on a journey to unveil the world of fire!

What is Fire? Which state is it? A solid or a liquid or a gas or plasma?

No, it is neither of them. Fire is just a perception of matter that is experienced by the eyes. Typically, fire results from a chemical reaction between oxygen in the atmosphere and a variety of fuels. When the volatile gases are hot enough, the compound molecules break apart, and the atoms recombine with the oxygen to form water, carbon dioxide, and other products. In other words, they burn, which results in a fire. The rising carbon atom is the reason for the production of light during the fire. Ignition temperature needs to be achieved for the combustion reaction to occur. During this reaction, the weak double bond of molecular oxygen gets converted into the stronger bonds of carbon dioxide and water, therefore, releasing energy, and this is the reason why fire is hot. The chemical reactions in a fire are self-perpetuating. The heat required by fuel is given by the heat of the flame itself, so as long as there is fuel and oxygen around it, the fire will continue.

FIRE TRIANGLE

FIRE: The Perception

The fire triangle is a triangle consisting of three components that help in the production of fire that are heat, oxygen, and fuel. Removal of any one of them will extinguish the fire. The alternative of the fire triangle is fire tetrahedron, which includes chemical reactions too, with all the other three components.

TYPES OF FIRE

  1. CLASS A- Fires involving ordinary combustibles such as wood, rubber, paper, cloth, and many plastics.
  2. CLASS B- Fires involving flammable gases such as gasoline, petroleum greases, tars, oils, oil-based paints, alcohols, solvents. It also includes combustible gases such as propane and butane.
  3. CLASS C- Fires involving energized electrical equipment such as computers, motors, transformers, and other appliances.
  4. CLASS D- Fires in combustible metals such as magnesium, titanium, zirconium, sodium, lithium, and potassium.
  5. CLASS K-Fires in cooking oils and greases such as animal and vegetable fats.

HOW FIRE SPREAD?

Once a fire has started, it grows through the transfer of heat energy from the flames. Heat energy transfers in three different ways-

  1. CONDUCTION- The heat from the fire spreads from molecule to molecule along the length of conducting materials. Materials that are good conductors absorb the heat from the fire and transfer it throughout the molecules of the substance.
  2. CONVECTION- It occurs in gases and liquids. It is the flow of fluid or gas from hot areas to colder areas. The heat of the fire raises the temperature of the air around it, which rises and spreads, which may burn the combustible materials.
  3. RADIATION- Heat of the Fire travels in the form of electromagnetic rays in air. Combustible materials can absorb the heat from the rays.

FIRE: The Perception

FIRE IN ZERO-GRAVITY

FIRE: The Perception

On earth, gravity determines how the flame burns. The product of combustion has more energy than the combustible substance and so moves around faster and takes up more space than the cooler air around them. Therefore, there is a buoyant force on them, which is higher than their weight. The hot gases in the flame are much warmer and less dense than the surrounding air, so they move upwards towards low pressure. This is why fire typically spreads upwards. However, in a zero-gravity region, there is no such thing as lighter or heavier air; thus, the fire heats the air, which just sits around the flame, causing it to burn slowly. This means the flame burns equally in all directions forming a globe instead of the flickering flame. Flames in the air can burn more slowly more coolly and with less oxygen because of which fire in space given the right conditions can expand in any direction as quickly as it can provide us to the nearby oxygen. The heat does not cause any rushing air or shockwaves. The cool thing found is that in space, combustion can happen with no visible flames. This phenomenon is demonstrated by the experiments conducted by NASA in the International Space Station, the Flame Extinguishment Experiment(FLEX). A more efficient combustion system that will not produce as much exhaust on earth can be made if these flames can be used as they burn cleaner.

FIRE: The Perception

FIRE SPREAD IN DIFFERENT SCENARIOS

  1. Fire in radioactive materials– Chernobyl incident was a nuclear accident in which radioactive material was present in the fire situation. Fire involving radioactive materials can result in widespread contamination. Radioactive particles can be carried easily by smoke plumes. Radiation includes alpha particles, which are extremely hazardous to people coming in contact with the fire because they can be inhaled and deposited in body tissues, where they can cause severe long term health effects.

FIRE: The Perception

  1. Fire in wood– Wood is a combustible material. Under the influence of heat, wood produces substances that react eagerly with oxygen, leading to the high propensity of timber to ignite and burn. Ignition and combustion of wood are mainly based on pyrolysis of cellulose and reactions of pyrolysis products with each other and with gases in the air, oxygen. When the temperature increases, cellulose starts to pyrolyze. The decomposition products either remain inside the material or are released as gases. Gaseous substances react with each other and oxygen, releasing a large amount of heat that further induces pyrolysis and combustion reactions.

Wood(C10H15O7)+heat —> Charred wood(C50H10O) + 10 CH2O(gas)

Forest fires include fire in a wood. Amazon forest fires and Bushfires in Australia are the major incidents, including the burning of wood. Fires in forests spread quickly due to the presence of combustible materials, which results in the realization of the fire triangle.

FIRE: The Perception 

  1. Fire in oil- Oils are flammable materials which are less denser than water, so floats on it. Disaster due to fire in oils includes oil well fires. Oil well fires are oil or gas wells that have caught on fire and burn. Oil well fires can be a result of human actions, resulting in accidents, which can be a result of arson or due to natural events, such as lightning. These fires are more difficult to extinguish than regular fires due to enormous fuel supply to the fire. The significant incidents include Kuwait Oil Fires and Deepwater Horizon Explosion.

FIRE: The Perception

Conclusion

Fire is a perception of our eyes to the exothermic combustion reaction. This is part of the Mini Analysis Project “Study and analysis of the phenomenon of Fire and it’s practical Implications through Case Studies”

This was an introductory blog describing the true nature of fire!

So ending this with a sneak peek of case studies we are going to elucidate in further blogs:

  1. Chernobyl Nuclear Disaster
  2. Australian BushFires
  3. Amazon Rain Forests

Intriguing blogs about the same coming soon…

Stay tuned until then.

REFERENCES

  1. “Glossary of Wildland Fire Terminology” (PDF). National Wildfire Coordinating Group. November 2009. Retrieved 2008-12-18.
  2. ^ Schmidt-Rohr, K (2015). “Why Combustions Are Always Exothermic, Yielding About 418 kJ per Mole of O2“. Chem. Educ. 92
  3. “Iraq Fires erupt in large Iraqi oil field in south Compiled from Times wires © St. Petersburg Times published March 21, 2003”. Archived from the original on July 15, 2014.
  4. ^ “Hellfighters”. Archived from the original on 2014-07-14.
  5. https://science.howstuffworks.com/environmental/earth/geophysics/fire.htm
  6. https://science.howstuffworks.com/environmental/earth/geophysics/fire1.htm
  7. https://www.space.com/13766-international-space-station-flex-fire-research.html

Author: Hardik Khandelwal

TEAM CEV!!

Rich Resources of SVNIT Surat

Reading Time: 2 minutes 

1.       Facility to download IEEE Research Papers for no cost through SVNIT  Local Area Network

IEEE is The World’s largest professional association for the advancement of technology. For us, it is a very good platform to read about all Research Papers written for all branches of Electrical & Electronics Engineers. But you need to be a member of that particular IEEE society to be able to download and read the paper. But!!! Our college provided us access to IEEE papers from our campus. So if you connect to IEEE website from our college LAN then you can access and download the papers!!!

So wait for what?? Read the latest research papers on various IEEE Societies mentioned onhttp://www.ieee.org/membership_services/membership/societies/index.html

Link to IEEE Explore for seeing a Research Paper of your interest- http://ieeexplore.ieee.org/Xplore/home.jsp

 

2.       Magazine and Journal Section in Central Library

Entering Central Library and on the second floor there is a Section for Magazines and journals for all branches which are the best way to stay in touch with the latest in technology. So go any explore your technical interest…..

 

3.       Reference Section 2nd Floor Central Library

We have a whole section of the best reference books for 100s different topics of all branches in our Reference Section. Avail that facility to read them and get your fundamentals crystal clear

 

4.       Digital Library – Store house of all well know Tech Journals ….

Go to svnit.ac.in -> Central Facility -> Central Library -> On Right Section Digital Library LINK

You need to login through our college LAN and then you can access various cool stuff like

E-BooksSpringler E-books, Cambridge University Press E-Book …….

E-JournalsScience DirectACM Digital Library, Institute of Civil Engineering Journals, Engineering Science Data Unit Series etc..

Purchased/Subscribed Standards

Previous Year Question Papers

Internship

Reading Time: 4 minutes 

Quoting what IIT Delhi Global Internship Program FAQ;s Have to say:

https://sites.google.com/site/aicetinterns/

 

  I am a student of the <>th semester, can I apply ?

Every student is (wrongly) advised by seniors to go for a internship at the earliest opportunity. Senior students often tell junior students (wrongly) that grades don’t count, and that projects are all that matter. They are wrong. Grades count – we look at your grades very carefully when we select you for the Internship.

The best time to go for a Internship is in the summer following Semester 6 + Semester 7 (nearly 9 months), or the whole of Semester 7 + winter + Semester 8 (almost a year). Without doing your discipline courses in Semesters 6 and 7, you could be very badly prepared for any internship.

Please try to follow the advice below when you choose your Internship period:

 If you are a student of Semester …. : Advice 
 Semester 1,2,3
  1. Please do not come for this internship or ANY internship for that matter in Semester 1-3.
  2. Take your textbooks for the next semester and study the chapters.
  3. Try to solve the questions and read alternative textbooks in the area.
  4. Also, do NOT join C# / .ASP / .NET coaching classes – such courses only reduce your study time. An employer will probably hire a programmer for these skills and not a software engineer. 

    Confused ? The difference between a software engineer and a programmer is like the difference between a doctor and a compounder. Both can administer a injection, perhaps even equally well – but only the doctor would knowwhy the injection was necessary. Even if the compounder, due to long practice, gets to administer the injecton more deftly than the doctor, the doctor will still be the only of the two who knows why. The compounder would always know just how to administer the injection.

    If programming also interests you, buy a good book on the language you want to program in, download linux (www.ubuntu.com) and learn it for free at home.

 Semester 4
  1. Please avoid coming for a Internship in Semester 4 unless there is something special you think you need to do. Special things could be going to Institute X because there is a Scientist X there who specialises in Algorithm Y, taking a course in a area not taught in your Institute next semester.
 Semester 5, 6
  1. Prepare for your Internship by doing all of the following:
    1. Read the latest journals in areas of interest every Friday – either in the library or on the net (see www.webproforum.com)
    2. Read alternative text books
    3. Read IEEE / IEE Journals for recent papers – don’t bother if you don’t understand everything at first (30% understood is good enough). Keep reading.
    4. Form Special Interest Groups (SIGs), meet on a weekly basis and discuss topics
    5. Give (voluntarily) a Weekly Seminar on what you read – you could give this to your Special Interest Group
    6. Talk to your own Faculty / lab technicians for possible projects you could do – whether in lab-oriented or theoretical projects.
    7. Start identifying faculty in your institute or outside your Institute in the areas of interest. Write to them.
      Do NOT write emails indiscriminately to hundreds of people – it will backfire on you when you are found out.
    8. Attend conferences, talks and lectures in your city.
    9. Watch Discovery, CNN, National Geographic and Eklavya.
    10. Join a local library. Visit the local University library. Read fiction and non-fiction. Take Art classes. Take pottery classes. Learn to play a musical instrument.
    11. Watch lectures of the courses you are being taught on YouTube.
    12. Read the course material of the courses being taught to you on MIT’s Open courseware site or IIT’s NPTEL site.
    13. Apply for Internship in time
 Semester 7,8
  1. Try to do projects within your Institute. Accomodation is not a problem. People know you and your background and the chance of being handed a task you cannot execute is minimal.

    On the other hand, a Faculty Member in another Institute is very likely to assume that you have done something in your coursework which you have not done.  You avoid all the following when you do your project in your own Institute ! It is no joke – it cuts into work time and influences work moods significantly.Only when it is absolutely unavoidable, go outside your Institute to do a Internship. And if you do go to another Institute, give first priority to availability of accomodation on campus even if it is marginally more expensive. This saves time and you get to meet more people in your peer group, have longer working hours and tend to achieve much more in your Internship.

    1. Coming to a strange city or a strange country
    2. getting accomodation, or even having to adjust yourself into a relative’s home for six long months
    3. having constantly worried parents
    4. dealing with indifferent food
    5. going through long commutes
    6. suffering irregular mealtimes

 

Things I would like to add:

2 most inspiring and knowledgeable novel that will change your thinking:

Fountainhead By Ayn Rand

 Outliers – Malcolm Gladwell

For ones who are not not good at programming read “The C Programming Language (Ansi C Version) 2nd Edition” written by creator of C – Dennis Rotchie. It costs only Rs 146!!! Link

For 1st yearites the best option to get their 1st year concepts right by watching videos @ NPTEL’s & MIT 1st year course for EC & Comps students Link1 Link2

Videos of Basic 1st and 2nd sem subjects. Just watch them at 1.5x speed as you may feel them to be bit slow!!!

 Few good place to look for Internships online: www.internshala.com, www.twenty19.com

+ List of Online Portal to see video lectures, projects, departmental magazines, some god father tech sites is provided in “Extra Edgy Things For All Engineers” Blog

Supplements for 1st and 2nd Year Chemies

Reading Time: 4 minutesHey 2nd Yearites . !!  As you are in 4th sem so first of all you might be thinking  what chemical engineering is…. We are not definitely studying it the way we used to study chemistry in XI or XII standard,instead of that we are with subjects like Electrical Technology, TMMD, Solid mechanics. I’ll tell you why these subjects are important. As chemical engineer you will be able to come up with technical solutions for problems and issues in relation to process and product technology. In finding these solutions, chemical engineers work closely with experts from other specializations, taking into account the related economical, social, environmental and ethical aspects of the problem they’re dealing with. To understand it let us see one practical situation wherein you have task to build up a transportation pipeline from point A to point B  and no qualified person is with you to help except one or two labourers. Your area of concern will be : 1) Angle of elevation of point A and point B from horizontal. 2) Diameter,length of pipe and which type of joints should be there? — So here comes Theory of machines and machine designing. 3) From what material pipe is to be made ? and what are the possibilities of failure of such a  structure? If pipeline is to be made underground then the nature of soil needs to be understood to avoid corrosion problems— So here comes Chemical Engineering Materials. Finally let’s say you have carefully made all arrangements and the pipeline is ready to use. And as you switch on the pump, you may not see the fluid coming out from the pipe!!Then what will you do??? What is the problem??? Problem was that you may not used proper motor which will provide you exact power or you have purchased correct HP motor but it is consuming more power, then you will go and see whether my motor is delta or star connected because every connection has its advantages and disadvantages. So if you have studied electrical engineering basics then you would have easily identified the problem.

  • Please don’t take any subject lightly or for the sake of getting marks. Strictly speaking what I think  from my experience is that an engineer should have the know of  basics of all disciplines of engineering. Now you may ask is coding and programming is going to help a chemie?? The answer is yes, because chemical process calculations are not as simple as solving an two variable equation and finding the answers. Practically any chemical  process or  even a small unit operation will have ‘n’ no. of variables so how you can solve them. So we need simulation software to handle these large no of variables. Now if you have basic “funda” clear in your mind that how it was designed and programmed.. You can handle the software much better than your colleague. But again I am not saying that you should be ‘phoodu’ in programming but basics are compulsory.
  • So, Chemical or process engineering is an interdisciplinary science comprising elements of mechanical Engineering, chemistry and technical physics.
  • The difference between chemical Engineering and process engineering lies in the emphasis of the degree course: while chemical engineers concentrate mainly on chemical processes, process Engineers deal primarily with the plants needed for this, their design and technical solution.
  • For General Chemical Technology (GCT) please watch you tube animation videos, NPTEL lectures. Also you can distribute these topics among your friends and then have a discussion for e.g. one can prepare about paper and pulp industry , other one on sugar industry and discuss among themselves.

I hope you are clear what are the application and importance of these subjects in the life of chemical engineer.

  • For first yearites : Observe the chemical processes occurring in day to day life and analyze them. See corrosion problems , how thermodynamics is playing in your home kitchen, analyze how propulsion systems works , analyze how energy sources like batteries, fuel cells, solar cells works.
  • Study alternate sources of energies such as bio diesel ( Jatropha seeds).Go through some basic outline of industries such as:Sugar industry, paper and pulp industry, soap and detergent industry….etc.
  • If possible visit as many industries as possible.
  • At the end of first year try to learn Microsoft Excel Software as much you can and C programming language in summer vacations.

 

  • For second yearites.. We dont have core chemical engineering subjects in 2nd year… So in 2nd year have active  participation  in techfests of various colleges; this will give you experience, direction , boost up your confidence and   will definately gives practical knowledge which helps when you will study core subjects such as (HTO, MTO, Thermo, CRE..etc)
  • You can participate in events like chemical car competition and chemistry related quizzes in 2nd yearand then in 3rd year you can participate in heat exchanger event …(I am saying this because there is a separate topic on heat echanger in 5th semester,so it is better to participate in this event later on in 3rd year.) … Do as per your interest.
  • Read magazines these are available in library, watch NPTEL lectures they are very good.
  • There are some free online courses available online these are given by profs of MIT , Harvard, Oxford, Stanford.. So make use of them. Most recommended courses are EDX and Stanford university online course.
  • My advice to you all is that don’t do industrial training in 2nd year.Instead  go to your seniors, profs and work under them  and learn as much you can from them. The best places for summer training  in chemical engineering some are: IITs, IISC , ISER, NCL, ICT, CSMCRI etc and in Private colleges we have very good Nanotechnology Lab at DDIT college in Nadiad. and in our college itself we have summer training programme so apply for that .

Some preferred courses: EDX

  1. our energetic earth
  2. Introduction to water treatment 
  3. Solar energy
  4. Introduction to solid state chemistry
  5. Thermodynamics
  6. Introduction to Drinking Water Treatment

STANFORD ONLINE COURSE

  1. Solar: Solar Cells, Fuel Cells and Batteries.
  2. Reservoir Geomechanics

Basics of Solar Cell Technology

Reading Time: 8 minutesSolar energy has enormous potential and it is highest among all the available sources of energy available whether it is renewable or non renewable sources. It is free, it is renewable and it is clean source of energy.

Now to begin, let’s start with one practical situation:

Assume that you have told to set up a solar power plant in India and you have given sufficient fund and land.  So what you will do??!!

Following are the points which you should think:

1) first you have to find a place in India where maximum solar power is hitting (Solar Ir-radiance ).solar-energy-distribution-india-map

 

2)      Lets say you have decided to put solar power plant in Gujarat. Now in Gujarat you have to see at what location exactly what amount of solar energy is hitting per square area.

Now we will  understand how it is calculated:

 

Any body which is above 0K  temperature will emit radiation according to planks law which is

given by:

download (1)

Above expression is for a body which is at particular  temperature and emitting radiation of a particular wavelength  but as we know body is  emitting radiations of all wavelengths from 0 to infinity. So we have to integrate that expression E(ƛ)d(ƛ) from o to infinity to find total emissive power emitted by the body.

Similarly consider sun as the source of solar radiations and earth is intercepting those radiations .the amount of solar radiation hitting on some area of earth will depend upon solid angle multiplied total emissive  power of sun.

rrr

 

So by doing integration of solar irradiance expression (emissive power) multiplied by solid angle of whole earth considering no atmosphere we will get a fix value known as solar flux and that is equal to 1367 W/m2.

Solar flux: The total energy flux (energy per time per area) incident on a unit area perpendicular to a beam outside the Earth’s atmosphere.

Air mass factor(AM): Air mass factor gives you idea about the relative position of sun w.r.t. to earth.

AM = 1/ CosƟ , where Ɵ equal to angle from vertcle line when sun is directly overhead to us.

download (3)

 

For e.g.  AM 1.5 = 1/CosƟ  => Ɵ=48.2*

AM0 means no atmosphere.

Now you have to calculate the solar flux which is hitting on your area in Gujarat. What you will do you will first of all find latitude of that area.

scs

After finding latitude we have to multiply that solar power density which is coming parallel to plane of equator with cosine of latitude because we want those photons which are hitting perpendicular to our solar cell.

 

3) So we have decided the location of power plant by calculating the exact solar flux hitting that area.

 

4) Now what next?? Before installing the solar panels we have to understand how solar cell works:

Working

  • The main part of solar cell is p-n junction. When p type and n type material are joined there is formation of space charge region/depletion region and It stays localized at the P-N junction and an electric field has been created.
  • If the solar cell is put in the sun, photons will strike the surface of the Silicon and pass their energy on to electrons. A typical photon can eject one electron from its nucleus creating a free electron and a vacancy. These free electrons will feel the effect of the electric field. They are pushed towards the junction on the N-side and away from the junction on the P-side. Likewise, the vacancy, which has a net positive charge, will be pulled towards the junction on P-side and pushed away from it on the N-side.
  • So there is current flowing from p type to n type material. This current is known as photo induced current and denoted by IL

 

1

  • This photo induced current generates voltage around load, but this voltage generation will also forward biased our p-n junction and there is another current  flows  through load known as forward biased current IF . so we will have net current I=I– IF   flows through our load.
  • Current vs voltage characteristics of our p-n junction is shown below:r3r
  • We can see from the graph that there is point where we are getting maximum power. so our aim is to find that point. This can be easily calculated by simple differentiation technique.
  • If still not clear , watch this video: https://www.youtube.com/watch?v=1gta2ICarDw

 

Efficiency

  • Efficiency is most important thing to any type energy system. We have reached maximum efficiency of  44% in case of solar cell.(search and find what are the efficiency of other sources of energy)
  • How to find efficiency of our solar cell???…

 

To find efficiency we have to first follow above procedure and calculate Jmax and Vmax

rgr

Above numerator term is Jmax* Vmax

Denominator is solar power denoted by Ps   at some AM value.

For e.g. Ps value at AM= 1.5 means

1367W/m2 *cos(41.8) =1000 W/m2

  5) After learning basics of solar cell, let’s build solar cell. Before we discuss the components of real solar cell,( just think what can be most imp building blocks of solar cell !!!  )

Following are the main components of solar cell:

  • P-n junction : Every p-n system is characterized by its unique band bap( ΔEg) or    forbidden energy gap.
  • Anti Reflecting Coating:  If ray of light incident on any surface ,some part is reflected and some part is transmitted.  we have to have maximize the transmittance .so we are applying the layer of such a material whose refractive index is the geometric mean of mediums which are above and below of anti reflective coating.

solar_cell

  • Glass: glass is used for two purposes first to concentrate the beam of light secondly to have self cleaning property so that any dust particle or any organic impurity can be washed off easily.

 

So to have self cleaning property of glass, two methods are used:

 

  1. We can coat a hydrophobic layer on glass which will make the contact angle for water – glass system to very large and consequently a spherical drop of water will from, which rolls down due to gravity taking away dust .
  2. We can coat a super hydrophilic coating on glass e.g. coating of TiO2. The glass cleans itself in two stages. The “photo catalytic” stage of the process breaks down the organic dirt on the glass using ultraviolet light and makes the glass super hydrophilic (normally glass is hydrophilic. During the following “super hydrophilic” stage, rain washes away the dirt, leaving almost no streaks, because water spreads evenly on super hydrophilic surfaces
  • Conducting wires: these are used to connect small -small solar cells into series and parallel.

Watch the below link to know how solar cell is manufactured. This video is of company- ‘’Sun Tech Power”.

https://www.youtube.com/watch?v=IAufbqbUS6k

6) Now you have installed solar cells and production is started. Now you have to know what maintenance is required and what are the factors which affects the performance of my cell.

Following are the factors which affects the efficiency of solar cell:

  • Loss of photons which are below the band gap:

This loss is highest among all losses. We know that light which is hitting contains photons of various energies but out of 100% photons only 30% are capable of generating current because a p-n junction is fixed for photon which have energy equal to band width rest are of no use.

g

There are multiple p-n junction kept one below the another and of variable band gaps.

 

  • Loss of energy from relaxation of carriers to band edges:

To understand this lets go to atomic level of p type material. This material when irradiated with some light electron will make jump from valence band to conduction band. Now this electron from the conduction band of p type goes to conduction band of n type via space charge region and during this journey electron losses its potential energy and relax at the band edges which results in dissipation of heat   as shown in fig:

rf

 

  • Resistance losses (shunt and series resistances) which will decrease Voc and photo current:

This is the second largest loss after loss of photons. Generally two types of resistances are there series and shunt .These resistances arises because of:

Series: 1. Resistence of connecting wires.

2. Contact resistances.

Shunt (parallel) : These are mainly due to impurities phases lying from  p type to  n type material .

  •  Junction recombination: electrons which are generated by light, some of them will lost while going through depletion region.
  • Optical losses :
  • Dirt accumulation on the glass :
  • Effect of temperature:  There is optimum range of temperature in which solar cell works efficiently ,Increasing temperature will decrease the cell efficiency.
  • Carrier recombination at defects: This effect is due to grain boundaries resulting in decrement of light current.

7) At last these are materials used in solar cell technology with their efficiencies:

aaa

 

In India we have largest solar park of Asia at Charanka village, Patan district, Gujarat. There is video on it : https://www.youtube.com/watch?v=kIhHy8X0kCg

Refrences:

Stanford university free online course: “solar cell, fuel cell and batteries”

 

Extra Edgy Things For All Engineers

Reading Time: 3 minutes

World Class Education Websites :- 

1.) edX.org

2.) coursera.org

3.) NPTEL.ac.in (watch at 1.5 x speed )

 

Internship and Workshop : Companies

 

1.) I3 Indiya

2.) Wegilant( Speacilized in Cyber Security)

3.) Robosapiens

4.) Technophilia

5.) Thinkware (Good for Matlab)

6.) Thinklabs

7.) Waayoo

8.) Learnics.in

9.) Logicbrigade.com

10.) STP.mbsgroup.in-(Also Has Course on F1 Car Design and Development)

 

To-Do Projects :-

 

Electronics Engineering

1.) SMPS

2.) POV

3.) LED CUBE

4.) FM Receiver

5.) Line Follower

6.) Temperature Controlled Fan

7.) Phone Jammer

8.) 555 Timer Projects

9.) Raspberry Pi

 

Mechanical Engineering

1.) Robotic Arm

2.) RC Plane

3.) Hovercraft

4.) Wall Climbing Robot

5.) Rope Climbing Robot

6.) Pole Climbing Robot

7.)Tricopter/Quadcopter

8.) Hydraulic Lift Arm

 

Chemical

1.) Batteries: Batteries of Your Own, like

  • Galvanic Cell
  • Zinc Air Battery
  • Al Air Battery
  • Al CU Battery

2.) Propulsion System: Car using

  • Vinegar+ Baking Soda
  • Decomposition of H2O2

3.) Search On MFC-Microbial Fuel Cell

4.) Research Alternate Source of Energy like Jatropha Seeds

 

 

 

 (continue on right column…..)

Electrical Engineering

1.) Power Generation from Moving Vehicles

2.) Power Theft Protection

3.) Booster Circuit

4.) Inverter Circuit

 

Civil Engineering

1.) Cardboard Model Building

2.) Designing On Softwares

3) Some Famous Civil Engineering Projects – Bridges, Tunnels and Dams

 

Computer Engineering

1.)Read: A Complete Reference to Java by Herbert Schildt

2.) Make Applets

3.) Android App Development

4.) Game Development

5.) AI-Artificial Intelligence: – Course on edX

6.) Read HTML: – HTML-5 for Web Development

7.) PHP

8.) Hacking

9.) Android- Learn to Root, Flash

10.) Google about Crack Paid Software using Decompiler and Disassembler!!!

11) Read  “C Programming Language” written by the creator of C – Dennis Ritchie

 

 

Extra-Edge Software

 

Civil

1.) Revit

2.) AutoCad

 

Computer Engineering

1.) Android App Development-IDE:-Eclipse

2.) Game Development Softwares

3.) Hacking-Backtrack OS

 

Chemical Engineering

1.) Aspen

2.) Super Pro Designer

3.) Open Foam

4.) Chemsketch

 

Mechanical Engineering

1.) Autodesk- AutoCad

2.)  Inventor

3.) Pro-e

4.) Google Sketch-Up

 

Electrical Engineering

1.) E-tap

2.) Matlab

3.) LabView

4.) PSCAD

5.) Simulink

6.) Lapack-Numerical Linear Algebra

 

Electronics

1.) MultiSim

2.) Proteus: Ckt and AVR MCU Simulation

3.) Eagle: PCB Designing

4.) Matlab: Mother of all things-

       Image Processing,Computer Vision,Control System Simulation, Digital Signal Processing

5.) NI’s LabView

 

Magazines

1.) ECE  – EFY

2.) Mech- Top Gear, Overdrive, AutoCar

3.) Chem- Chemical Engineering, World,Chemical Industry Digest

4.) Comps- Digit, Chip

5.) Electrical- Industrial Automation (IED Communications),IET(generation transmission and distribution)

 

Tech Fests

Even Semester

1.) IIT Bombay -Techfest Jan first week

2.) IIT Madras -Shaastra   Jan first week

3.) IIT Kharagpur -Kshitij Feb first week

4.) NIT Trichi-Pragyan-Feb End

5.) IIT Kanpur -TechKriti   March Mid

6.)BITS Pilani -Apogee   March Mid

7.) IIIT Hyderabad -Felicity

8.) IIT Roorkee -Cognizance

 

Odd Sem

1.) NIT Surathkal-Engineer – October End

2.) NIT Warangal-Technozion-   September End

 

God Father Sites

 

1.) http://www.howstuffworks.com/(Discovery’s Site-More of general Science)

2.) http://www.engineersgarage.com/

3.) http://www.extremeelectronics.com

4.) http://www.circuitstoday.com/

5.) www.societyofrobots.com (The best according to me)

6.) http://www.electronics-tutorials.ws/

7.) http://www.ece101.com/

8.) http://narobo.com/

9.) http://www.pyroelectro.com/

10.) http://students.iitk.ac.in/roboclub/tutorials.php

 

Electrical Engineering

1.) controleng.com

2.) control.com

3.) electric.net

4.) controlglobal.com

 

Mechanical Engineering

1.) pirate4x4.com

2.) carbibles.com

3.) SudhaCars.com

 

 (Continue on right column ……)

Computer Engineering

1.) code.org

2.) codechef.com

3.) spoj.com

4.) Java Applets-http://walter-fendt.de/ph14e/

 

Others

1.) internshala.com

2.) knowafest.com

3.) twenty19.com

 

 

Sites to buy robotics stuff

In India:

1.) http://nex-robotics.com/

2.) http://www.robokits.co.in/

3.) http://www.vegarobokit.com/

4.) http://www.rcbazaar.com/default.aspx

5.) http://www.rcdhamaka.com/

 

World best online robotics store:

1.) Jameco

2.) Solarbotics

3.) Digi-key

4.) Radioshack.com

 

Movies

1.) Gravity

2.) October Sky

3.) Iron Man-1, 2, 3

4.) Wall-E

5.) Batman

6.) G I Joe-1, 2

7.) Transformers-1, 2, 3

8.) The Social Network

9.) Avatar

10.) Real Steel

11.) Pirates of Silicon Valley

12.) Blade Runner

13.) 2002: A Space Odyssey

TELEVISION SHOWS

 

Discovery, Discovery Science, Discovery Turbo

1.) How Tech Works

2.) Dark matters

3.) Extreme Engineering

4.) Deconstructed

 

History TV

1.) Modern Marvels

 

NatGeo TV

1.) Big, Bigger, Biggest

2.) MegaStructures

3.) MegaFactories

4.) I Didn’t Know That

5.) Ultimate Factories

6.) Mega Factories

 

 

Mindbend Indeaz -Some Problems & Basic & Best Solution

Reading Time: 6 minutesArtificial Growth of algae & subsequent drain of nitrogen based chemicals.

  • While searching for technical solution, one has to keep in mind that technology should not induce other problems while solving one problem.
  • Also when we say water management it’s not controlling our limit of use but to artificially induce natural recycle process by studying nature. The best way to tackle waste is to match it with waste utilization. Manipulation of waste is like shifting it from one system to another without actually reducing the same.
  • Here I will be talking on a method that study natural water recycling method and adoption of the same instead of chemical processes which solve one problem and create another.

Eutrophication:-

  • Eutrophication can be human-caused or natural. Untreated sewage effluent and agricultural run-off carrying fertilizers are examples of human-caused eutrophication. However, it also occurs naturally in situations where nutrients accumulate (e.g. depositional environments), or where they flow into systems on an ephemeral basis. Eutrophication generally promotes excessive plant growth and decay, favoring simple algae and plankton over other more complicated plants, and causes a severe reduction in water quality. Phosphorus is a necessary nutrient for plants to live, and is the limiting factor for plant growth in many freshwater ecosystems. The addition of phosphorus increases algal growth, but not all phosphates actually feed algae. These algae assimilate the other necessary nutrients needed for plants and animals. When algae die they sink to the bottom where they are decomposed and the nutrients contained in organic matter are converted into inorganic form by bacteria. The decomposition process uses oxygen and deprives the deeper waters of oxygen which can kill fish and other organisms. Also the necessary nutrients are all at the bottom of the aquatic ecosystem and if they are not brought up closer to the surface, where there is more available light allowing for photosynthesis for aquatic plants, a serious strain is placed on algae populations. Enhanced growth of aquatic vegetation or phytoplankton and algal blooms disrupts normal functioning of the ecosystem, causing a variety of problems such as a lack of oxygen needed for fish and shellfish to survive. The water becomes cloudy, typically colored a shade of green, yellow, brown, or red.
  • Naturally Algal blooms occur when excess of plant nutrient (Nitrates & Phosphates) is available in the water-A natural cleansing process.
  • These blooms have been found to destroy fishes in fresh water because of the low oxygen level initiated by planktons feeding on algae after death at the lower water level.
  • It has been found that the root cause of imbalance in water is excess of nitrates & phosphates. So the target should be root cause.
  • Thus we could encourage algal growth for nitrate reduction outside the fresh water body & thereby decrease the nitrate & phosphate level and also increase food for planktons /phosphorous fixating bacterias/nitrogen fixating bacterias-which are then eaten by marine life-A natural phenomenon initiated artificially.
  • The excess of algae may be used as a bio-diesel or may be fed by phytoplankton to zooplanktons to small fishes to large fishes & the eco-logic continues.
  • Well traditionally ion exchange methods used in industries are used for nitrate reduction however nitrates do not go away from system they are just removed from water source & they appear in other system.eg:-

In ion-exchange resins the nitrate ion is removed from water source by exchanging with chloride ions. After the exchange the nitrates present in the resin bed are exchanged with HCL to regenerate resin producing HNO3 .thus we see that still overall system –the eco-system has nitrates still left & will somehow or other reappear. Also the chlorides that we exchanged are also as dangerous as nitrates if present in large quantity. So any chemical process is a curtain to existing problem it no longer solves problem as a whole. A bio-chemical process is therefore best by observing nature.

  • Also biological dentrification is used in which nitrates are converted to Nitrogen gas.
  • The process is similar to denitrification done by anaerobic bacterias but those require organic food in plenty to convert nitrates ultimately each natural process comes down to bacteria and microbes level as they are natural scavengers but those attract pests and rodents bad odor etc.

Disadvantage:-

  • The time algal growth requires, the time planktons & other organism requires to complete a food-web is high .hence this system may be only used in areas where there is no continuous addition of nitrates-small industries letting off waste in 5 days, a farming site where agricultural run-off carries phosphates & nitrates during rainy season, a waste water treatment plant having large base for each pond for cultivation.

Use of reflectors as flyers controlled by the control station to reflect the amount of power in a cellular structure:-

  • In a cellular structure the transmitting & receiver (duplex antenna) is one that radiates micro-waves for mobile communication. Generally in urban areas where concentration of mobile phones is very high the towers are placed on residential towers or offices or shops etc.
  • There is a growing debate on whether the electromagnetic exposure can cause tumors or cancer. Although few researchers have shown the opposite but practically over exposure to micro-waves can definitely lead to a disorder because these waves tend to heat the body temperature when they pass through our body. The tissues break in to cells creating disorder in the body due to high temperature.
  • Even though limits of radiation are standardized by government ,continuous exposure is dangerous for all of us. people living near towers face high dangers of exposure while people far away likely do not .since power density of the antenna is high near the antenna & starts reducing as the distance increases.
  • So we can direct a high powered beam of radiations towards a secondary tower flying in the sky over a cellular structure at heights calculated for power required & that can be used as a transmitter receiver to be communicated with the base station.
  • This will always ensure uniform power spread & the affect of heat effect of micro-waves would be reduced.
  • This will ensure constant power density on surface of earth (exceptions hills, mountains etc.) to be used for purpose of communication rather than concentrated power density.

 

Disadvantages:-

  1. Mobile base station makers will have to share extra costs for making new equipment controllable from control tower as well.
  2. Finding out space in the sky for installing each such station over which we can place the flying station which will not be interfered by birds, airplanes, ionosphere reflection, etc.

Possibility/Feasibility:-

A free wireless internet service for developing economies called “Project Loon” was announced by Google & initially was surveyed in New-Zealand by a farmer for wireless internet by sending balloons carrying transponders receptors & efficient mechanism for looming around a particular region just like a geo-synchronous satellite. This will also be in India, South-Africa.

An ICT model for empowering rural population:-

Our government spends 60000 crore in Nrega-a scheme which is aimed at providing opportunities for employment in 100 days. A worker from rural area is made to toil for breaking stones & he gets his income from that. With bundles of corruption, this scheme neither utilizes individual potential of a farmer, a child, a painter, a porter goldsmith etc. to meet their expenses rural public do .Instead of this each village can have a “centre of internet” where everything that an urban Indian gets rural India also has.

 

  • Healthcare:

Supply of generic medicines as when needed, supply essential supplements for maternal ,child health through a WLAN connections each in one village, asking possible diagnostic questions to doctors who are unwilling to go to rural side, people will tell their day to day activities & doctors would suggest diseases that can occur or a database of diseases in different languages.

  • Entrepreneurship:

Popularity of village & direct details of those involved in sale of those materials online.

  • Current trends of market:

Current Wheat, Rice, Moong, etc. to give farmers a fare share of their products

Giving their new inventions on web may be integrated with National Innovation Foundation (NIF).

  • Education.

 

Applications & Basics of Bucky Paper

Reading Time: 5 minutesBuck paper is an arrangement of carbon nanotubes in some desired fashion and orientation or we can say buckypaper is a macroscopic aggregate of carbon nanotubes (CNT’s).

The specific properties of bucky paper depends upon arrangement of CNTs . These properties include :

1)EMI ( electro- magnetic interference) Shielding.

2)Strength .

3)Electroconductivity.

4)Thermal stability.

By adding the resin and the hardener to the buckypaper and then curing it in a specific temperature and pressure, the buckypaper composite will be produced.

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Fig 1.                                                                              Fig 2

Fig1 shows picture of bucky paper composite.

Fig 2 shows SEM image of bucky paper.

Now before going in detail about bucky let us talk about its building block –CNT . We will learn what it is , its types , its preparation methods and properties.

Carbon Nanotube

Carbon is having 3 forms of allotropes: graphite, diamond and fullerene, and if we talk about graphene it has two dimensional hexagonal sheets one above the other.

Picture2Picture1Picture3

So if we roll  that two dimensional sheet we get CNT is a tubular form  with diameter as small as 1nm and length in few nm to microns.Picture4

The way that graphene is rolled up drastically change physical properties and we get different types of nanotubes.

We can define the nano tube in terms of the equation : Ch = n â1 + m â2,

Ɵ is Chiral Angle with respect to the zigzag axis and a1, a2 are chiral vectors.

The coefficients n, m define what kind of nanotube it is. For e.gPicture5

n= m armchair nanotube

m=0  zig-zag nanotube

n ≠ m chiral nanotube

and under some conditions such as n-m =3r where r= 0,1,2..we get metallic nanotubes otherwise semiconducting nanotubes.

 

Picture61So we can say that- The values of n and m determine the chirality, or “twist” of the nanotube. The chirality in turn affects the conductance of the nanotube, it’s density, it’s lattice structure, and other properties. A SWNT is considered metallic if the value n – m is divisible by three. Otherwise, the nanotube is semiconducting. Consequently, when tubes are formed with random values of n and m, we would expect that two-thirds of nanotubes would be semi-conducting, while the other third would be metallic.

Types of carbon nanotubes: 

A)Single walled carbon nanotube                 B) Multi walled carbon nanotube

 

 

MWCNTS are concentric nanotubes.

 

 

Preparation methods:

As CNT is a thin two dimensional graphene sheet we will first learn how this grapheme layer is prepared. The simplest method to produce  graphene layer is chemical method.

Procedure:

1)Take graphite powder cooked it in acid (cons H2SO4) with an oxidizing agent (cons  HNO3), thus will give graphite oxide.

2) Graphite oxide will then reduced to give graphene.

3) now this graphene is in solution form , put this solution on any substrate we get graphene layer.

Fig3 below shows schematic procedure of chemical method.

Picture9

Second method most important method is Arc Discharge method.

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This is the most common and perhaps easiest way to produce carbon nanotubes as it is rather simple to undertake. In this method two carbon rods placed end to end, separated by approximately 1mm, in an enclosure that is usually filled with inert gas (helium, argon) at low pressure (between 50 and 700 mbar) as shown in Figure 4. A direct current of 50 to 100 A driven by approximately 20 V creates a high temperature (~4000K) discharge between the two electrodes. The discharge vaporizes one of the carbon rods (anode) and forms a small rod shaped deposit on the other rod (cathode).

Third method is Chemical Vapour Deposition (CVD):

In short we can say that here we have a chamber in which substrate + catalyst is present and gas(carbon source) comes in and there will be:

Steps:

  • Adsorption
  • Dissociation of hydrocarbon.
  • Dissolution and saturation  of C atoms in metal .
  • Precipitation of Carbon.
  • Picture2

Properties of CNT:

  • Mechanical : Young’s modulus of the single walled carbon nanotubes (SWCNTs) can be as high as 2.8-3.6 TPa and 1.7-2.4 TPa for multiwalled carbon nanotubes (MWCNTs) which is approximately 10 times higher than steel, the strongest metallic alloy known.

Application:  the high stiffness and strength combined with low density implies that nanotubes could serve as ideal reinforcement in composite materials and provide them great potential in applications such as aerospace and other military applications.

  • Electrical: They can be can be metallic or semiconducting depending on their structure and their band gap .  Theoretically, metallic nanotubes having electrical conductivity of 105 to 106 S/m can carry an electric current density of 4 × 109 A/cm2 which is more than 1000 times greater than copper metal .

Application:  So the high electrical conductivity of CNTs makes them an excellent additive to impart electrical conductivity in otherwise insulating polymers. Used in fuel cell technology.

  • Thermal: SWCNT has a room-temperature thermal conductivity along its axis of about 3500 W m−1 K−1 and MWCNTs have a peak value of ~ 3000 W m−1 K−1 at 320 K; compare this to copper, a metal well-known for its good thermal conductivity, which transmits 385 W m−1 K

Application: thermal management applications, either as “heat pipes” or as an alternative to metallic addition to low thermal conductive materials,heat sinks that would allow computers and other electronic equipment to disperse heat more efficiently than is currently possible

 

Preparation of Bucky paper

 

Now we have CNT’s ready with us in both forms SWCNT’s and MWCNT’s. We have to put these nanotubes in some desired fashion to form bucky paper,figure shown below clearly explains the procedure to do it:

Picture9Picture3

 

This is just the basics of bucky paper or CNT, if someone have to study in detail their is an excellent video  lecture from Prof C.N.R Rao, check it :

https://www.youtube.com/watch?v=8WwXAwBAtfg

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