...century was the isolation of graphene. Graphene is a thin layer of pure carbon; it is a single, tightly packed layer of carbon atoms that are bonded together in a hexagonal honeycomb lattice.1 If we stack these thin layers upon each other it forms graphite, which is found in every pencil lead. When isolated, graphene exhibits remarkable properties that can be used to help improve the performance and efficiency of current materials and substances. Graphene was first studied theoretically in the 1940s. During this time, scientists felt that it was physically impossible for a 2D material to exist, so they did not pursue any form of mechanical exfoliation. Decades later, interested sparked and researchers began trying to peel apart the layers of graphite to isolate graphene. Scientists tried various techniques, but they never got to a single layer. Eventually, they were able to isolate graphene on top of another material, but not on its own. In 2003 a physics professor and his PhD student achieved the impossible; they were the first to isolate a single layer of graphene. Andre Geim, who won the 2000 Noble Prize for levitating a live frog over a magnetic field,2 asked a new PhD student to see how thin he could make a piece of graphite. That student Kostya Novoselov, was only able to produce a sample around 1,000 layers thick, but set in motion a side project for Geim that would turn into the scientific find of the century. After speaking with friends and colleagues, Geim and Novoselov...
Words: 551 - Pages: 3
...and Thermal) in two allotropic forms of Carbon (Diamond and Graphite) Graphite and Diamond both are formed from carbon (two allotropic forms of carbon). Though they have similar constituent element, they differ a lot in their properties. Diamond is a good thermal conductor but a bad electrical conductor, while graphite is a bad thermal conductor but a good electrical conductor. This is one example of their property difference. The difference in their properties arises because of different arrangement of carbon atoms present in them. Basic physical and chemical properties of graphite and diamond to highlight their differences are as follows: Differences between Graphite and Diamond Physical Appearance: Graphite is opaque and metallic- to earthy-looking while diamonds are transparent and brilliant. Another important physical difference is their hardness. The hardness of minerals is compared using the Moh's Hardness Scale, a relative scale numbered 1 (softest) to 10 (hardest). Graphite is very soft and has a hardness of 1 to 2 on this scale. Diamonds are the hardest known natural substance and have a hardness of 10. Diamond is used as an abrasive because of its great hardness, whereas graphite is used as a lubricant. Structural Differences: Diamond Space Group Fd3m face-centered cubic Atoms/unit cell 8 Cell volume 45.385 x 10-24cm3 X-ray density 3.5155 g/cm3 {draw:frame} Graphite Space Group C6/mmc; C-centered hexagonal Lattice parameters...
Words: 913 - Pages: 4
...from Latin: carbo "coal" is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity. There are several allotropes of carbon of which the best known are graphite, diamond, and amorphous carbon. The physical properties of carbon vary widely with the allotropic form. For example, diamond is highly transparent, while graphite is opaque and black. Diamond is among the hardest materials known, while graphite is soft enough to form a streak on paper (hence its name, from the Greek word "to write"). Diamond has a very low electrical conductivity, while graphite is a very good conductor. Under normal conditions, diamond has the highest thermal conductivity of all known materials. All carbon allotropes are solids under normal conditions with graphite being the most thermodynamically stable form. They are chemically resistant and require high temperature to react even with oxygen. The most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and other transition metal carbonyl complexes. The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil and...
Words: 8042 - Pages: 33
...A Magic Blanket That Is Effective Against Cancer, Insomnia, Autism and Many Other Health Issues Temple Grandin is a professor who invented the squeezing machine. She invented this machine to help her with her own sensory needs since she deals with autism on a daily basis. According to Dr. Grandin this machine is beneficial for children with ADHD – attention deficit hyperactivity disorder and children with autistic disorder. The side effects of the squeezing machine are minimal. Autism is a heterogeneous disorder. If a treatment is effective for one child, it does not mean that it will be effective for another. The squeezing machine will be excellent for autistic people who face over-sensitivity problems. Autistic people who have more cognitive problems and less sensory problems are less likely to benefit from this machine. The Grandin’s machine applies adjustable pressure. The pressure stimulates the feeling of being hugged. People with Aspergers, Autism and sensory disorders feel better when weight is pressed against them. The pressure from the weight of these blankets increases the production of endorphins and serotonin. The body naturally produces these chemicals in order to feel more calm and relaxed. The blanket is effective for people who suffer from the following disorders and health problems: • Autism spectrum disorder – ASD • Asperger’s syndrome • Attention deficit hyperactivity disorder –ADHD/ADD • Anxiety • Aggressive Behavior • Alzheimer’s disease • Agitation...
Words: 718 - Pages: 3
...on the world, but graphene has the potential to propel us further into the 21st century with astounding technological might. Much like the introduction of plastic and rubber, graphene will play a role in how we live our lives. Shaping the way we work, eat, live, and play. However, in order to understand how this wonder material will change lives, we must understand what it is, define its potential uses, and overcome the significant hurdles in cheap and efficient production. Graphene can best be described as a one atom thick layer of graphite. It was first discovered in 2004 by Andre Geim and Konstantin Novoselov at the University of Manchester. It is a 2-D crystalline allotrope of carbon, the world’s first 2-D material in fact. An allotrope is just a different arrangement of carbon, like diamond for example. Due to its sp2-hexagonal arrangement, graphene exhibits special properties. Most forms of carbon exist in a sp3 arrangement, (like graphite in the image above). What this means is that graphene can exist in a 2D state. Due to this configuration electrons are free to move across the whole compound with relative ease. Endowing it with remarkably high electron mobility. This ability allows any current to easily make its way through the molecule; making it a prime supercapacitor, meaning it can charge really quickly and give off that energy just as fast. It also exhibits incredible tensile strength, making the strongest intrinsic material ever discovered. When in a pristine...
Words: 864 - Pages: 4
...combining power with other different atoms when it is in the process of forming chemical compounds or molecules. The most common allotropes are Diamond and Graphite. The different allotropes of carbon tend to shows different properties and have a different application in different fields. Diamond is a common allotrope of carbon that exhibits hardness and has a high ability to disperse light. Diamond is the hardest discovered mineral and industries find it useful in cutting and drilling of other elements. It is also used to manufacture jewelry. Graphite is another common allotrope of carbon. Graphite is formed in a single layer by graphene that consists of carbon atoms and it is arranged in a single plane. Graphite is a good electric conductor. Graphite is known as the most stable form of carbon under the rating of standard conditions. This paper will describe the chemical and physical compounds and their industrial application in different fields. Discussion Allotropy refers to a property of a particular chemical element that exists in more than one different form when it is found in nature. There are different forms of carbon that exists and this paper will discuss the common allotropes and their application in different fields. The first allotrope of carbon is a diamond. The diagram above shows the comparison between diamond and graphite. Diamond The chemical structure of this allotrope of carbon is arranged in a lattice, which tends to resemble cubic crystal structure. Diamond has...
Words: 2013 - Pages: 9
...Nanotechnology (first used the term nanotechnology by Richard Feynman, in 1959) can be defined as the manipulation of atoms and molecules at nano (one billionth) scale (1–100 nm) to produce devices, structures or systems having at least one novel or superior property. The materials having at least one dimension in the nano scale are called nanomaterials. 10-9 meter (1 nanometer) to 10-7 meter (100 nanometer) Human eye can visualize up to 20μm only 1μm = 10-6 m DNA= 2.5nm- 3nm Protein= ̴ 5 nm Virus= ̴ 150 nm Human hair= ̴ 5000 nm Properties of Nanomaterials 1. The surface area to volume ratio of the nanomaterials is relatively larger than that of bulk materials of the same mass. This increases the chemical reactivity and affects strength and electrical properties of the material. 2. The quantum confinement is observed at nanometer sizes that changes the optical, electronic and magnetic properties of the material. The band gap increases as the size of the material is reduced to nanometer range. I II III IV Reduction in particle size increase in its Surface area Now, material is NANO so surface area will big… HOW? Let us consider a sphere of radius ‘r’ Surface Area = 4 x π x r2 Volume = (4/3) x π x r3 ratio of SA to Vol = 3/r Thus, radius of sphere decreases, Surface area will increase Let us consider a cube of sides 1 m Area= 6 x side2 = 6 x 1m2 = 6m2 Now, cut the same cube into 8 pieces, then the SA will increases Area= 6 x (1/2)2 x 8 = 12m2 Similarly, the...
Words: 2807 - Pages: 12
...ABSTRACT Simplified mechanisms are presented for the growth of DLC films. The role of hydrogen and oxygen in the deposition is mentioned and detailed reactions are shown for one of the existing models of amorphous hydrogenated carbon film growth (a-C:H). The subplantation process for hydrogen free amorphous carbon (a-C) is discussed. A simple application example for the growth of a-C:H film using an oxygen-acetylene torch is included. INTRODUCTION Several review papers portray the preparation and state of the art of DLC films [1-5]. There are basically two different types of DLC films: amorphous hydrogenated carbon (a-C:H), and amorphous carbon (a-C). They are differentiated on the number of sp3 (diamond like) vs. sp2 (graphite like) bonds, and the role that hydrogen (or OH) plays in the formation and structure of the film. A diamond like structure exists when sp3 bonds form between carbon atoms during the growing of a carbon film. The sp3 fraction is defined as: (Eq. 1) As the sp3 fraction increases the film tend more towards diamond properties and behavior. Diamond is a crystal with sp3 fraction of 1. The first kind of DLC, that we will refer to as Amorphous Hydrogenated Carbon (a-C:H), hydrogen plays a fundamental role. A diamond like structure will not form without the presence of hydrogen, which can have a concentration up to 50% (atomic) of the final film obtained. The sp3 fraction in a-C:H films is usually less than 50%. There are an assortment of...
Words: 2213 - Pages: 9
...Weighted blankets are blankets filled with either glass beads or more frequently plastic pellets, used for the purpose of calming the nervous system of children and adults with neurological disorders such as autism, sensory processing disorder and, attention deficit hyperactivity disorder as well as other mental and physical disorders. The pressure the weight delivers causes a release of serotonin and melatonin, chemicals that help to maintain mood levels and regulate sleep. Weighted blankets should be sensory friendly, useful, comforting, affordable and, easy to clean. SensaCalm weighted blankets are an excellent sensory and therapy tool with a plethora of uses and provide many benefits to those who use them. With the neuro-divergent as their primary consumer, weighted blankets should be as soft and sensory friendly as possible. SensaCalm’s weighted blankets come in many different types of fabrics including chenille, cotton, flannel, and fleece. The blankets are very soft to the touch but still incredibly sturdy. They come in a wide variety of colors and patterns, featuring everything from solid white to spaceships to cartoon characters. The blankets are filled with odorless, non-toxic poly pellets and stuffed with hypoallergenic stuffing. With so many options, in both fabrics and patterns it is nearly guaranteed SensaCalm will have a blanket available for everyone no matter their tastes or sensitivities. As a moderately pricey item, SensaCalm’s weighted blankets need...
Words: 810 - Pages: 4
...i) Electrodes that connect power supplies to liquids that conduct electricity. Due to the fact that graphite is a prime conductor of electricity it is used to make electrodes. Graphite is a prime conductor of electricity as the structure and the movements of electrons have the ability to move from one end of the sheet to the other. The moving of the electrons can transfer heat across the molecule. ii) A powder that can be used to polish gemstones. Diamond powder can be used to polish gemstones. This is because diamond has an extremely strong structural formation, where the atoms are arranged in a manner when they have the inability to maneuver. With the strong atom arrangement of this allotrope it allows diamond to be an ideal tool to scrape away dirt particles of gemstones, leaving the remaining surface smooth and with the absence of any rough areas....
Words: 470 - Pages: 2
...50th Anniversary Edition I, Pencil My Family Tree as Told to Leonard E. Read FOUNDATION FOR ECONOMIC EDUCATION 30 South Broadway Irvington-on-Hudson New York 10533 1-800-960-4FEE • 914-591-7230 www.fee.org “I, Pencil” is a superb case study of free markets in action. Half of the world’s economic problems would vanish if everyone would read “I, Pencil.” Burton W. Folsom, Jr. Professor of History Hillsdale College b There is no better, more easily understood, and more fun explanation of the complexity of markets than Leonard Read’s “I, Pencil.” It ought to give considerable pause when we listen to the arrogance of politicians who tell us they can manage an economy better than millions, perhaps billions, of independent decision makers in pursuit of their own personal goals. Its message to would-be planners is to bug out! Walter E. Williams John M. Olin Distinguished Professor of Economics George Mason University b The most valuable truths about economics and liberty can be found in a lowly lead pencil. When my children are old enough, I will read them a classic little essay by the late philosopher Leonard E. Read that turns a mundane writing instrument into an elementary lesson about free-market capitalism. Michelle Malkin Syndicated columnist b I, Pencil My Family Tree as Told to Leonard E. Read Introduction by Lawrence W. Reed Afterword by Milton Friedman This edition of “I, Pencil” is dedicated to our late esteemed colleague, Beth A. Hoffman,...
Words: 4221 - Pages: 17
...The Uses of The Nanotechnology Carbon Nanotubes and Graphene. This report will be about the scientific research and development, Carbon Nanotubes and Graphene. I will be covering the advances it could create, as well as the hurdles it will be experiencing during its research of both. While Carbon Nanotubes are soon to be obsolete to Graphene, it presents a foundation for the development and inspiration of Graphene. First I will start with carbon nanotubes. The way carbon nanotubes are produced is through multiple growth methods. One of them is Arc Discharge, which is done by running a 100 amp current through the carbon soot of graphite electrodes. It produces 30% of the weight into both single and multi-walled nanotubes with lengths of up to 50 micrometers with structural defects. Another method is Chemical Vapor Deposition, which uses a substrate that contains metal particles, commonly nickel, cobalt, iron, or a combination. The substrate is heated to approximately 700°C, and then they bleed two gases into the reactor: a process gas like ammonia, nitrogen, or hydrogen, and a carbon-containing gas like acetylene, ethylene, ethanol or methane. Once that, and a couple other, more complex processes are performed, the carbon-containing gas is broken down, and the carbon is transported to the edges of the particle and the substrate, where it forms the nanotubes. The mechanism is still being studied, and others are also being performed as well as other methods of production. The...
Words: 877 - Pages: 4
...and silicon in the sand are combined to form SiC and carbon monoxide gas. The temperatures in the core is around 2200° to 2700° C and about 1400° C at the outer layer of the furnace. The electricity requires to form the SiC is enormous and it could around 100,000 kW-h required per run. After completion of one run about 40 hours, the product consists of a core of green to black SiC crystals formed together, surrounded by partially or entirely unconverted raw material. The lumped product aggregate is crushed, ground, and screened into various sizes appropriate to the end use. Fig 2.1 Acheson’s Electrical furnace Acheson’s furnace has two electrodes which are connect to a graphite core laid within a surrounding mixture of reactant carbon, salt and sand. When an electric current is passed through the graphite core, it heats the surroundings, resulting in the formation of SiC and the expulsion of carbon monoxide (CO) gas. The main raw materials Quarts (SiO2) and C which are made to react at high temperature around 2700°C. Saw dust and salt are also added, so that saw dust burns and provides pores facilitating escape of evolved gases (at high temperatures). Firing is done for 40 hours and after cooling, the side walls are removed. The chemical reaction inside the reactor is producing the SiC which done step by step process from silica sand (SiO2) and carbon. Can be written as: 1. SiO2 + 3C = SiC + CO Beta type SiC is produced through the gaseous intermediate (SiO) with the...
Words: 1353 - Pages: 6
...1 The analysis of Graphene material Alinur Mirassov, Azat Yerkinova, Gaukhar Balbayeva Madi Aldabergenov, Takhmina Torgayeva Abstract: Recently, graphene has attracted the interest of significant number of scientists and physicians due to its exceptional properties (e.g., large surface area, thermal and chemical stability, high conductivity). This new member of the carbon family has potential to revolutionize the current applications (some of them are described in the essay) as well as creating new set of applications. In this paper, we review the background of the novel material, its comprehensive atomic structure and properties that has fascinated the scientific community since its discovery. We also cover the synthesis of the material, including different effective methods that was investigated from the year of discovery until the present day. Finally, we discuss possible challenges and future perspectives in this rapidly enhancing scientific area. Key words: Graphene; Graphene-based material; 2-dimensional (2D); monolayer; Carbon nanotubes; Dirac level; fullerene; nanostructure; graphene synthesis; graphene applications. Reference to this paper should be made as follows: Aldabergenov, M., Balbayeva, G., Mirassov, A., Yerkinova, A. & Torgayeva, T. (2013) ‘The analysis of Graphene Material’, Astana: Nazarbayev University. 1 Introduction With the time movement and generation flow, the science and engineering achievements expands and widens by...
Words: 7015 - Pages: 29
