Thursday, June 20, 2019

Larix International Material Science Conferences


Larix International is a group of ranking publishers and organizer’s for scientific conferences around the globe nesting well-known Doctors, Engineers, Scientists, and Industrialists. Larix is a self-functioning, independent organization wholly focused on arranging conferences in multi-disciplines of research on various science fields. The conferences are administered by global influential scientists and scientific excellence. We are even open for the upcoming scientists and scholars, who are in need of a platform to give their voice a much needed larger volume.

World Summit on Advanced Materials and Engineering (MATSCI 2019) is going to be organized in the beautiful city of Singapore on June 20-21, 2019 at Holiday Inn Atrium, primarily focusing on the theme “New materials and new technologies”.


Material Science

Materials science is an interdisciplinary field involving the properties of matter and its applications to various areas of science and engineering. It includes elements of applied physics and chemistry, as well as chemical, mechanical, civil and electrical engineering. With significant media attention to nanoscience and nanotechnology in recent years, materials science has been propelled to the forefront at many universities, sometimes controversially. In materials science, rather than haphazardly looking for and discovering materials and exploiting their properties, one instead aims to understand materials fundamentally so that new materials with the desired properties can be created. The basis of all materials science involves relating the desired properties and relative performance of a material in a certain application to the structure of the atoms and phases in that material through characterization.


ALL ABOUT IT

There is a wide range of applications for Materials Science and Engineering. A mix of chemical, mechanical, and civil engineering. Traditional MSE focused on metallurgy, where you look at the effects of heat treating and doping (adding other elements) to extract metal from the ground and give it specific properties. Think about the chemistry and physical process to get gold, iron, and copper out of the dirt in the ground (ore).  And the end products like spring steel, stainless steel, aircraft grade aluminum, chrome plated rims.  In aerospace, they need materials that are strong, even at extreme temperatures, usually special ceramics or composites.

In electronic materials, there is research in everything from OLED TV screens to quantum computing. Even the manufacture of tiny computer chips uses lithography, which is an application of materials science.

There are bio-materials, where research is being done to improve the quality of dental implants and hip replacements, among other materials that would be in contact with, or embedded in the human body... 3D printed tissues are becoming a popular area, e.g. for organ replacements and burn victims.

Building materials like Drywall can now be lighter weight, tougher, and better at damping sound, and even absorbing volatile organic compounds, thanks to materials engineers.
Extending the life of a nuclear reactor comes down to inspecting all the materials, and checking if and why materials are degrading. This can mean millions or billions in savings, and it requires experts to ensure the right calculations are made, ranging from Corrosion to pressure to heat and mass transfer...

And when things go bad, specifically when there are catastrophic failures, materials science, and engineering allows us to determine how and why something failed, both to determine who is liable to the insurance companies can hash it out, and prevent similar catastrophes from happening again.

Polymers and composites are used to make lightweight materials used in race cars and sports equipment.

DISCUSSIONS

Material Science and Engineering; Ceramics and Composite Materials; Electronic and Magnetic Materials; Mining, Metallurgy and Materials Science; Emerging Smart Materials; Materials Chemistry and Physics; Manufacturing Innovations; Nanomaterials and Nanotechnology; Characterization & Testing of Materials; Biomaterials and Medical Devices; Materials in Industry; Petroleum Chemistry
Electronics and Photonics; Graphene, Fullerenes and 3D Materials; Polymer Science and Technology; Smart & Hybrid Materials; Industrial Engineering; Electronic Material Development Ceramics & Composite Materials.

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Tuesday, April 2, 2019



How to produce a metal lighter than water but stronger than titanium?

A metal that can revolutionise the technology of energy efficiency. Engineers in University of Pennsylvania named it “Metallic Wood” as it is light enough to float in water.




















Metallic wood foil on a plastic backing. Credit: University of Pennsylvania

Titanium — the stuff of hip implants and aircraft parts — is strong and light. Aluminum is even lighter, but not as strong. High-performance golf clubs and airplane wings are made out of titanium, which is as strong as steel but about twice as light. These properties depend on the way a metal's atoms are stacked, but random defects that arise in the manufacturing process mean that these materials are only a fraction as strong as they could theoretically be. An architect, working on the scale of individual atoms, could design and build new materials that have even better strength-to-weight ratios.

In a lab at the University of Pennsylvania, engineers have created an improbable material that is as strong as titanium while putting aluminum to shame in the weight department. The material contains no actual wood, but it is wood-like in the sense of having pores: air spaces in between billions of miniature “struts” of nickel. Magnified thousands of times on a microscope, the material looks like honeycomb.

‘Metallic wood’ at Penn is as strong as titanium but lighter than water


“It’s like a scaffold,” said James Pikul, an assistant professor of mechanical engineering and applied mechanics.


So far, the engineers have made just small squares of the material — each about the size of a postage stamp — but they envision that it could be produced in large enough quantities to make rugged, ultralight exteriors for cell phones and other electronic devices. Depending on the cost, it might be an option for making lightweight, fuel-efficient cars.


Magnified about 12,000 times, this ultralight "metallic wood" made at the University of Pennsylvania has the appearance of honeycomb or a sponge.
Magnified about 12,000 times, this ultralight "metallic wood" made at the University of Pennsylvania has the appearance of honeycomb or a sponge.

In collaboration with engineers at Illinois and the University of Cambridge, he published his findings in January in the journal scientific reports.

The process for making metallic wood is sophisticated yet easy to describe.

Start with billions of tiny plastic spheres suspended in a small vial of water. Insert a substrate — a strip of glass-like material that conducts electricity — and heat up the water. As the water evaporates, the spheres settle on the strip in an orderly pattern, stacking themselves almost like a pyramid of oranges in a grocery-store display.











Stacked plastic spheres, white, provide a framework for nickel, blue, and are ultimately dissolved away. Once there is an open lattice of nickel, other functional coatings, yellow, can be added. Credit: University of Pennsylvania

James Pikul, an assistant professor of engineering at Penn, describes how to make "metallic wood" in his lab. In his right hand, he holds a substrate that is used in the process.
James Pikul, an assistant professor of engineering at Penn, describes how to make "metallic wood" in his lab. In his right hand, he holds a substrate that is used in the process.


Then “electroplate” the spheres with nickel, much like chrome is used for plating shiny car parts. That means placing the strip coated with spheres into a solution of nickel ions, then applying an electrical current, causing the nickel to coat the surfaces of the plastic balls.

Add a solvent to dissolve away the plastic, and presto! What’s left is a porous scaffold of nickel.
The process is modelled after the way nature creates opals, which are formed from microscopic spheres of a substance called silica. But because the spheres in metallic wood are dissolved away, it is called an inverse opal. Like the gemstone, Pikul’s metallic wood radiates a rainbow of colours when held at certain angles, as the microscopic pores are just the right size to interfere with the wavelengths of visible light.

Pikul and his colleagues have made metallic wood with densities ranging from one-tenth to one-third that of solid nickel.

It makes sense that a porous metal would be lighter than a solid. But how does it remain relatively strong?
The key is the small size of the nickel struts. Larger pieces of metal tend to have the occasional defects and gaps at the atomic level, sapping their strength. But in very small samples, such defects tend to rise to the surface and disappear, Pikul said.

That means his nickel scaffolds are small but mighty, able to shoulder a heavy load relative to their weight. Laboratory tests indicate they have a compressive strength on par with titanium. Pikul and graduate student Zhimin Jiang now are testing the tensile strength of the material, carefully tugging it apart on what looks like a miniature rack from a medieval torture chamber.

Other researchers in the field of nano-materials are taking notice, among them Timothy J. Rupert, an associate professor of materials science and engineering at the University of California, Irvine.
Though it takes the Penn team a whole day to make a small square of metallic wood, Rupert said it is easy to imagine producing the material on a cost-competitive, industrial scale. One promising application would be automotive manufacture, he said.

“One could imagine making a car with the same safety standards used today but a much, much lighter weight,” Rupert said. “This would have huge implications for energy efficiency.”

Pikul has not yet grappled with how to produce his material in such large quantities, but he looks forward to the challenge. If he could make really big slabs of metallic wood, it might even be useful as a high-tech structural component in a building, he said. It likely would be expensive compared with other building materials, but the microscopic pores could be a plus for circulating air in hotter climates.

Call it an inverse opal or metallic wood: With this material, he has only begun to scratch the surface.

If you find this topic interesting please share, comment and tweet.



Reference: https://bit.ly/2CQwY03 


Friday, March 29, 2019

How to produce Perfect Plastic ?

Memorial University Scientists say carbon dioxide has the solution.


Devastating effects of plastic on Environment

The damage to the environment by plastic use needs to be controlled.The biggest problem with this is that once they have been soiled the end up in the trash, which then ends up in the landfill or burned. Either solution is very poor for the environment. Burning emits toxic gases that harm the atmosphere and increase the level of VOCs in the air while landfills hold them indefinitely as part of the plastic waste problem throughout the globe.

Beach_strewn_with_plastic_debris
Marine debris that was washed ashore covers a beach on Laysan 
Island in the Hawaiian Islands National Wildlife Refuge.

It has been estimated that one bag has the potential to unintentionally kill one animal per every three months due to unintentional digestion or inhalation. If you consider the number of littered plastic bags ranges from 1.5 million to 3 million depending on location, this equals a lot of ecosystem sustaining lives lost.

plastic_land_dumps
Burning of plastic

Without the balance of the ecosystem food sources dry up and starvation occurs. With an increase in plastic bag use throughout the world, the eventual effects could be literally devastating even to the human population.

How MUN researchers are working toward a biodegradable plastic.
This purified polymer could be cast into a film used to make an 
environmentally friendly alternative to plastic bags.

With the provincial government continuing its research on the possibility of banning single-use plastic bags, graduate students in chemistry at Memorial University are researching new materials that would make bags biodegradable.

Kori Andrea says it would likely be difficult to ban plastics altogether, but she's part of a team of researchers working to create a better, more environmentally friendly alternative that would break down at the end of its life.
Andrea said she's using the carbon dioxide abundant in the environment as the basis for new biodegradable materials.
"What we're looking at is being able to take carbon dioxide and actually use it as a starting material in these polymers or plastics that we're making," she said.
"We're taking carbon dioxide, we're reacting it with another starting material called epoxides, and then making these alternating polycarbonates, and these are your plastics."
Reactions with carbon dioxide are done at high pressure and 
yield this material. Some trapped carbon dioxide can be seen 
in bubbles. (Kori Andrea/Submitted)
Andrea said many plastic materials now in use are made from petroleum products, which are built with carbon-hydrogen bonds and don't easily decompose.

"It's hard to break down because if you think of the organisms and bacteria in the environment today, they don't have to break down bonds like that, so of course, everything bio-accumulates over time," she said.
"With incorporating carbonate linkages, these carbon-oxygen bonds in our materials, there are bacteria out there that are capable of breaking these things down."

Modifying materials

It's a case of "Mother Nature knows best," Andrea said, using raw materials that fit with natural processes.
Andrea said some of these biodegradable plastic-like materials are already being made by companies in the United States and the United Kingdom, but they have drawbacks.
She said she and other researchers at MUN are modifying the materials they are making to make them more heat-resistant for things like lids for paper coffee cups, or to have different densities to mimic different pre-existing materials.
"We're looking at taking our materials and alternating them one way or another — can we make something similar to a plastic wrap that's very flexible? Can we make something similar to what milk jugs are made of that's a bit more durable?" said Andrea.
"We have recently found some different ways to modify them and start to really change their melting points or their durability. We are getting there. We're still at the fundamental stage and the development on the lab scale."

Scaling up

The challenge now, she said, is to make these products on a large scale with existing technologies and equipment.
Andrea said high pressure is needed to make the carbon dioxide react, so she's designing catalysts to make those reactions occur without high pressures or temperatures.
But it's hard to know what the end products will cost until they are scaled up to produce larger quantities.
"Can we make them? Yes. Can we make them cheaper than the processes that have been optimised for 50-plus years? I don't think we're there yet," she said.
"But will we get there? I think we definitely will."
Is it not cool that Carbon dioxide, a commonly known hazardous gas can be used to balance ecosystem ?
Comment below and share your thoughts.

Wednesday, March 27, 2019

Can a small lump of iron (unearthed in Turkey) will cause a paradigm shift in the chapter of Metallurgy's origin ?

Ancient iron-making included iron products processed from iron meteorites ?

The oldest-class ironmaking-related relic found in the Kaman Kalehoyuk ruins in the Anatolia region of Turkey (Provided by the Japanese Institute of Anatolian Archaeology)

A small lump of iron found in ancient ruins in Turkey may upend commonly held beliefs about the history of ironmaking, as the relic appears to have come from somewhere else.
The question is, where?
A Japanese research team uncovered the oldest ironmaking-related relic of its class at an excavation site in the Anatolia region, the central area of the Hittite Empire (1,400 B.C.-1,200 B.C.).
The empire was a major power along with the New Kingdom of Egypt in the ancient Orient.
The relic is a weight-shaped lump with a diameter of about 3 centimeters and contains a high amount of oxidized iron.
The Japanese Institute of Anatolian Archaeology (JIAA) of the Middle Eastern Culture Center in Japan (MECCJ) discovered it in September 2017 in a geological layer dating between 2,500 B.C. and 2,250 B.C.
The institute has been engaged in research into the Kaman Kalehoyuk ruins in Turkey since 1986.
The ruins are in the central area of the Hittite Empire that prospered in the ancient Orient by using iron and light tanks as weapons.
The empire is said to have acquired military advantages by adopting ironmaking invented by indigenous people. In those days, ironmaking was considered the most advanced technology.
After the empire collapsed, the ironmaking technology spread to surrounding regions, and the proliferation became a turning point toward the Iron Age.
According to JIAA director Sachihiro Omura, the unearthed relic is believed to be the oldest of its kind in the history of ironmaking.

Traces of buildings from more than 4,000 years ago, seen from above, found at the Kaman Kalehoyuk ruins in the Anatolia region of Turkey. Wooden materials that served as the foundation for the structures are set in the reddish-brown scorched soil layer. The holes are believed to have been used for storage. (Provided by the Japanese Institute of Anatolian Archaeology) 

It has been commonly believed that ironmaking originated in the Anatolia region. However, the institute's analysis of the relic showed that it was produced in a different area and brought into the region.
Iron products from the early period of the history of ironmaking include those processed from iron meteorites.
The institute thus asked Takafumi Matsui, professor emeritus of comparative planetology at the University of Tokyo, to analyze the relic.
Taking advantage of the world's most advanced technologies in microfabrication and precision analysis used to look into fine particles brought back from the Itokawa asteroid in 2010 by the Hayabusa space probe, the analysis examined cross-section surfaces of iron compound particles with a diameter of about 0.1 millimeter that the relic was composed of. The results showed that the composition of the particles differed from that of iron meteorites.
As the analysis showed a composition of concentric circles that appear when heat was artificially applied, it was determined that humans produced the lump from iron ore using fire.
Sachihiro Omura stands next to a scorched soil layer (reddish-brown part), which was newly found in the Kaman Kalehoyuk ruins in the Anatolia region of Turkey, in August 2017. The oldest-class ironmaking-related relic was found just above the layer. (Provided by the Japanese Institute of Anatolian Archaeology) 

The analysis also looked into the composition of a small amount of lead in the relic, and then found that the proportion of isotopes was different from that of iron ore widely produced in the region.
Based on the results of the analysis, Matsui said: "The lump is probably a semi-manufactured product processed from iron ore to the middle stage. Someone likely brought it from a distant region."
The team unearthed several similar lumps found just above a 1-meter-thick scorched soil layer about 12 meters beneath the ground's surface.
Traces of buildings found in the same geological layer as the lumps showed that people dug into the scorched soil, constructed foundations for the buildings by installing wooden materials and made walls of mud.
The scene of excavation at the Kaman Kalehoyuk ruins in the Anatolia region of Turkey in September 2017 (Provided by the Japanese Institute of Anatolian Archaeology)

The construction style differed from that of the region, which mainly uses sun-dried bricks.
"It shows that an ancient city that existed there was destroyed on a large scale, and then a group of people came to the area, which was swept up by flames, from the north," Omura surmised.
He added that at the time, ironmaking technologies of the initial period were likely brought to the area simultaneously.
"By making further comparisons with iron ore of other regions, we'd like to figure out where ironmaking originated and clarify the key role played by Anatolia in the arrival of the Iron Age," he said.
Tatsundo Koizumi, representative of the Institute for Archaeological Education of Mesopotamia, said, “It's an extremely important discovery that has a big impact, as it proposes a shift in the common sense of world history put forth by European and U.S. authorities.”
The challenges, he added, are to pinpoint the place of origin of the lumps and clarify how ironmaking spread and developed in Anatolia.
“To determine who invaded the region and left the scorched soil, it is necessary to gather more knowledge about various regions in a careful manner," he added.


Tuesday, March 26, 2019

Relation between Material Science and Ice-Skating is "COOL".

Physical Chemistry explains the slippery nature of Ice. 

Romantic couple ice skating outdoor on the frozen lake by RG&B Images for Stocksy United

The low friction of ice is why speedskaters can reach 35 mph, why figure skaters can twirl in dizzying circles, and why a 40-pound curling stone can glide and accomplish whatever the heck the point of curling is.
But for much of the past two centuries, scientists have struggled to explain why, exactly, ice is slippery — and why skates can glide atop it so well (or for that matter why it’s so easy to slip walking on ice).
One obstacle: Skates on ice are surprisingly hard to study. You can’t see what’s happening when a blade is cutting through the ice because the blade obscures the view. And the ice layers that skates glide on are microscopically thin.
So scientists have to rely on their knowledge of physics and chemistry for an explanation. They’ve come up with a few overlapping ones that each elucidate a fascinating property of ice. Given that winter cold has settled over the Northern Hemisphere, it’s a good time to dig in.
Ice is solid water. You know that. But what happens when it becomes a solid makes this substance unusual and fascinating.
For most substances in the universe, the solid phase is denser than the liquid phase. When a material is cooled enough to form solids, its molecules get bonded in tight arrays. But ice is different. When it drops below 32°F, the special hydrogen bonds that link water molecules together force additional space between the water molecules when they freeze.
On the left, molecules of liquid water are disorganised and dense. 

On the right, molecules of ice are orderly and spread out.

And it turns out you can fine tune ice to benefit athletes in different sports.
As Smithsonian Magazine explains, the ice used in rinks in the Olympic ice is purified water, sprayed on rinks one layer at a time to create surfaces of flawless consistency. The thickness and temperature of the ice in the Olympics depends on the sport. Figure skaters prefer ice set close to the melting point at 25°F for extra grip and control. Hockey players like a colder, harder, and ultimately faster surface.
Solid ice is actually less dense than liquid water (this is why icebergs float in the ocean). And for scientists, this was a clue to figuring out why ice is so darn slippery.

Hypothesis 1: Pressure melts ice. (This is mostly wrong. But still interesting.)

Since the 19th century, the most common answer to the question of “why is ice slippery” has been “because ice melts under pressure.”
This idea draws from the work of James Thompson, who in the 1850s worked out the math that describes a very strange property of ice: That is, under high pressure, ice turns back into water. This is due to the fact, again, that solid ice is less dense than water. If you squeeze ice, it becomes less stable and melts.
You can demonstrate this effect with a very simple experiment. Take a length of wire and tie a weight to each end. Then lay the wire across a large block of ice. The pressure of the wire will cut a clean line through the ice (which will freeze back together once the wire passes through, a process called “regelation”). Watch this video: https://youtu.be/1iIv1SuS164
It’s tempting to think this is how ice skates work — that the pressure exerted by the thin blade on the ice melts enough water to reduce the friction and allow for gliding.
But here’s the problem: “You’d have to be an incredibly massive person in order to melt ice sufficiently to be able to skate at any reasonable temperature,” David Limmer, a theoretical chemistry professor at UC Berkeley, said in an interview last year.
As the New York Times’s Kenneth Chang has explained, a 150-pound person standing on blades would only lower the melting point of ice from 32°F to 31.97° F., while ice rinks for figure skating are commonly kept around 24°F. Simply put: Skaters can’t exert enough pressure to melt the ice.
“So while the basic idea is correct — you can melt ice by pressurizing it — the numbers don’t work out at all,” Limmer says. (One paper explains if the ice is a very cold -4°F, it would take a pressure of 39,680 psi to melt enough to allow for skating. That’s more than double the pressure found at the bottom of the ocean! And yet it’s still possible to skate on ice that cold.)
Also, pressure melting doesn’t happen instantaneously, as you can see in the video above. “So it’s inconceivable that in the millisecond that a skater spends when on a certain spot on the ice, one can simply, by pressure, melt a layer of water,” Hans van Leeuwen, a retired professor of theoretical physics who has recently published a mathematical explanation of ice skating, said.

Hypothesis 2: Friction melts the ice. (Getting warmer. But it doesn’t explain everything.)

So the pressure of a thin blade on ice cannot explain why skates glide. But what about friction? Can’t the sliding motion of ice skates on the surface generate enough heat to melt the ice?
This is definitely part of the answer, but it doesn’t explain why ice is so unusually slippery to begin with. Anyone who’s walked on a slick sidewalk knows you can slip on ice the second your foot touches it. And that’s not enough time to generate the friction necessary to melt a film of water.
Friction “is a second-order effect” in the ice skating problem, Limmer explains. Friction helps us understand why ice skates can glide faster and faster when moving, but not why they can get started in the first place.

Hypothesis 3: There’s a very small layer of liquid water on top of ice. (This is key.)

A few years before James Thompson explained why pressure melts ice, physicist Michael Faraday discovered another fascinating property of ice: the thin, liquid layer on its surface. His experiment was so simple you can do it at home.
Take two ice cubes in your freezer, and very quickly — so as to not heat any part of them to their melting point — stack them on top of each another.
Come back a few hours later. They’re stuck together.
Faraday (correctly) guessed that the ice cubes stick together because of the liquid layer surrounding them. When these liquid layers meet, they freeze together.
This very thin liquid layer also makes ice extra smooth. But Faraday couldn’t prove his hypothesis at the time. The science of atoms and molecules was not yet available to aid in the explanation.
In 1987, scientists verified the existence of this “quasi-liquid” layer with X-ray imaging. And it’s super, super thin. The best estimates find its thickness at -1°C (30.2°F) is between 1 nanometer and 94 nanometers. That’s about 1,000 times smaller than a bacteria. More recently, scientists have actually seen the liquid surface using extremely sensitive microscopes.
diagram showing what’s happening on a molecular scale.
When water is frozen, the individual water molecules grab each other via hydrogen bonds, holding one another in place in a crystalline structure, as you can see in the lower half of the figure. But the molecules on the surface have fewer other molecules to cling to, which makes them more disorganized — and ultimately makes the ice slippery.

To summarise with

A British team short track speed skater practices in preparation for the 2014 Sochi Winter Olympics.

So what happens when an ice skate made from aluminum or steel touches the ice?
Van Leeuwen explains that the tiny liquid layer is the reason why skates can start moving instantaneously on ice. And as the blades move faster and faster through the ice, more friction is generated, which melts more water. As the skater propels forward, she physically plows through the ice, deforming it. This causes more friction, and more melting. All this allows skaters to glide, hydroplane-like, on a thin, thin film of water in a channel they carve. And this all happens in an instant.
Again, all this would be a very hard thing to see firsthand in an experiment. “The thickness of the layer of water is so small that you can’t distinguish it from the ice,” Van Leeuwen says. So it stands as a hypothesis for now.
But interestingly, Van Leeuwen estimates it would be very hard to skate at temperatures below -30°C. Even though there would still be a tiny liquid layer on the ice, it would take too much friction to generate enough heat to melt anything else. Also, below this temperature, the tiny liquid layer on top of ice becomes harder and harder to detect. It would be like skating on gravel. (Though why in the world you would want to go skating at -22°F is beyond me.)

What else can we skate on?

Okay. Case closed. But I was left wondering: Are there any other surfaces we could skate on? As Limmer explains, “basically all solids” will form a tiny liquid layer “when they are close to their melting temperature.”
Mercury freezes at -37.89°F. It would take far too much energy to keep a rink of mercury that cold. Plus, mercury is a potent neurotoxin.
What about gallium? It’s a metal that melts at 85.58°F — a little hot for a skating rink. But just imagine skaters doing triple axels on a silvery mirror gallium surface. “That sounds like a wonderful idea,” Limmer says. (Just make sure your skates aren’t made out of aluminum!When aluminum interacts with gallium it becomes very brittle.)
Though solid gallium would be more slippery near its melting point, would it be slippery enough for ice skating? Or easy enough to plow through? There’s only one way to find out.
Reference: https://bit.ly/2UWxDEb