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Four New Elements Officially Added to Periodic Table

The International Union of Pure and Applied Chemistry (IUPAC), which verifies claims of newly discovered elements, has announced that four new super-heavy elements have cleared the verification process and are now officially recognized.

The recognition of these four new elements completes the 7th row of the Periodic Table of the Elements, a table which most people studied in their high school chemistry class. Researchers consider the discovery and verification of new elements to be an honor greater than winning an Olympic gold medal, given that it is such a rare occurrence. In fact, researchers are already hard at work attempting to create elements in the lab that would begin an 8th row of the Periodic Table.

Teams from around the globe had created all four of these elements using particle accelerators to smash atoms together. None of them are stable elements, decaying into lighter particles almost instantly after their creation.

A press release from IUPAC provides the details of the announcement:

The fourth IUPAC/IUPAP Joint Working Party (JWP) on the priority of claims to the discovery of new elements has reviewed the relevant literature for elements 113, 115, 117, and 118 and has determined that the claims for discovery of these elements have been fulfilled, in accordance with the criteria for the discovery of elements of the IUPAP/IUPAC Transfermium Working Group (TWG) 1991 discovery criteria. These elements complete the 7th row of the periodic table of the elements, and the discoverers from Japan, Russia and the USA will now be invited to suggest permanent names and symbols. The new elements and assigned priorities of discovery are as follows:

Element 113 (temporary working name and symbol: ununtrium, Uut)
The RIKEN collaboration team in Japan have fulfilled the criteria for elementZ=113 and will be invited to propose a permanent name and symbol.

Elements 115, 117, and 118 (temporary working names and symbols: ununpentium, Uup; ununseptium, Uus; and ununoctium, Uuo)
The collaboration between the Joint Institute for Nuclear Research in Dubna, Russia; Lawrence Livermore National Laboratory, California, USA; and Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA have fulfilled the criteria for element Z=115, 117 and will be invited to propose permanent names and symbols.

The collaboration between the Joint Institute for Nuclear Research in Dubna, Russia and Lawrence Livermore National Laboratory, California, USA have fulfilled the criteria for element Z=118 and will be invited to propose a permanent name and symbol.

The priorities for four new chemical elements are being introduced simultaneously, after the careful verification of the discoveries and priorities. The decisions are detailed in two reports by the Joint Working Party (JWP), which includes experts drawn from IUPAC and IUPAP (the International Union of Pure and Applied Physics). These reports will be published in an early 2016 issue of the IUPAC journal Pure and Applied Chemistry (PAC).The JWP has reviewed the relevant literature pertaining to several claims of these new elements. The JWP has determined that the RIKEN collaboration have fulfilled the criteria for the discovery of element with atomic numbers Z=113. Several studies published from 2004 to 2012 have been construed as sufficient to ratify the discovery and priority.

In the same PAC report, the JWP also concluded that the collaborative work between scientists from the Joint Institute for Nuclear Research in Dubna, Russia; from Lawrence Livermore National Laboratory, California, USA; and from Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA (the Dubna-Livermore-Oak Ridge collaborations), starting in 2010, and subsequently confirmed in 2012 and 2013, have met the criteria for discovery of the elements with atomic numbersZ=115 and Z=117.

Finally, in a separate PAC article the Dubna–Livermore collaboration started in 2006 is reported as having satisfied the criteria for discovery of element Z=118.

“A particular difficulty in establishing these new elements is that they decay into hitherto unknown isotopes of slightly lighter elements that also need to be unequivocally identified” commented JWP chair Professor Paul J. Karol, “but in the future we hope to improve methods that can directly measure the atomic number, Z“.

“The chemistry community is eager to see its most cherished table finally being completed down to the seventh row. IUPAC has now initiated the process of formalizing names and symbols for these elements temporarily named as ununtrium, (Uut or element 113), ununpentium (Uup, element 115), ununseptium (Uus, element 117), and ununoctium (Uuo, element 118)” said Professor Jan Reedijk, President of the Inorganic Chemistry Division of IUPAC.

The discoverers now have the opportunity to propose permanent names that conform to IUPAC’s guidelines, so sometime later in 2016 the new official Periodic Table will be published with those newly named elements. See the press release on the IUPAC website for additional details.

Source: IUPAC.org – “Discovery and Assignment of Elements with Atomic Numbers 113, 115, 117 and 118“

New Technology Cuts Mining Water Recycling Process from Decades to Hours [Video]

Cleaning up the water left over from mining operations can literally take generations—25 to 50 years on average—leaving billions of gallons of the precious resource locked up and useless.

Now, researchers have figured out how to trim that time dramatically—to just two to three hours. The advance could be a potential boon to mining companies, the environment, and global regions where water is scarce.

“I think the ability to save water is going to be really big, especially when you’re talking about China and other parts of the world,” says Mark Orazem, professor of chemical engineering at the University of Florida.

Mining operations use water for mineral processing, dust suppression, and slurry transport. When they’re finished with it, the water holds particles of mineral byproducts, known in the phosphate mining business as clay effluent.

In the case of phosphate mines that are so common in Florida, the clay effluent has the consistency of milk. “It looks like a solid, but if you throw a stone into it, it’ll splash,” Orazem says.

The water is pumped into enormous settling ponds—some are as large as a mile square with a depth of about 40 feet—where the particles can sink to the bottom. Florida alone is home to more than 150 square miles of such ponds, an area that would cover about half of New York City.

But it’s a lengthy process because the particles are electrically charged. Like charges repel and opposite charges attract. The particles’ like charge causes them to repel each other, which keeps them suspended in the water instead of sticking together and sinking to the bottom.

WATER IS ‘REUSED, AND REUSED AND REUSED’

That means mining companies can re-use the water only a bit at a time—the part skimmed off the top. Not only is the particle-filled water useless, the land those settling ponds occupy is a valuable asset that could be used for other purposes.

Ideas for speeding up that process go back centuries. In 1807, an early application of the battery invented by Volta in 1800 showed that clay particles moved in response to an electric field. In the 1990s, an electric field was used to separate clay and water in batches, but that concept was deemed uneconomical.

The new design is different because it allows a continuous feed of clay effluent into a separation system. There, upper and lower plates are used as electrodes. An electrical potential difference is applied across the electrodes, creating an electric field, which causes the charged particles to move toward the bottom, where they form a wet solid called a cake. In the cake dewatering zone, the particles can’t move, so the water is forced to the top.

The cake can then be used to fill the holes created by the mining operation, while the water is now clear enough to be reused to process mined phosphate ore.

“Instead of having the water tied up in these clay settling areas, water is sent back through the process and then reused and reused and reused,” Orazem says.

The researchers have created a lab-sized prototype and say the next step is to determine how to scale it up to a point where it can work in a real-world mine.

While the concept was designed for Florida phosphate mines, it could be used anywhere and would be especially useful in arid North Africa. In Morocco and the Western Sahara, with 85 percent of the world’s phosphate reserves, water is especially in short supply.

“Recycling water is going to be critically important,” Orazem says. “So in Florida, it’s an issue. In the desert, it’s going to be a major issue.”

The Universe’s Most Miraculous Molecule

Richard Gunderman, Indiana University-Purdue University Indianapolis

It’s the second most abundant substance in the universe. It dissolves more materials than any other solvent. It stores incredible amounts of energy. Life as we know it would not be possible without it. And although it covers more than 70% of the Earth’s surface, many parts of the world are in dire straits for lack of it. What is it?

The answer, of course, is water. In some ways, water is one of the substances we know best, in part because it makes up 75% of our bodies. Every day we drink it, bathe in it, clean with it and use it to dispose of our wastes. Yet scientists are still striving to understand many of water’s remarkable properties, and the 21st century will force us to think about water like we never have before.

What makes water so remarkable?

For most of human history, water was considered to be one of the four elements, along with air, earth and fire. It was only in the 18th century that chemist Antoine Lavoisier passed an electrical current through water and realized that it gives off two gases: hydrogen (literally, “water maker”) and oxygen.

The formula of water is H2O – two atoms of hydrogen and one of oxygen. One of water’s most remarkable properties is traceable to the hydrogen bonds that continually form and reform between its slightly negatively charged oxygen and slightly positively charged hydrogen components. Thanks to these bonds, water molecules attract one another far more strongly than those of almost any other substance.

These hydrogen bonds give water a very high specific heat, meaning that it takes a great amount of energy to warm it. It also has a remarkably high boiling point compared to other chemically similar molecules, such as hydrogen sulfide. These properties enable human beings to dissipate large amounts of heat during exercise by perspiring.

Another consequence of hydrogen bonding is capillary action (the topic of Einstein’s first paper), which occurs, for example, when a liquid is drawn up between the hairs of a paintbrush. The water molecules attract one another so strongly that they defy the force of gravity. When water evaporates from the highest leaves of a tree, it draws up other water molecules from the roots far below.

Still another consequence of hydrogen bonding is water’s high surface tension. This accounts for its tendency to form droplets and enables some insects literally to walk on water. This force can be so strong that premature infants, who lack surfactant, a substance that lessens it, can become exhausted just trying to inflate their lungs. Fortunately, surfactant is now available as a medication.

The fact that water has slightly positively and negatively charged poles also makes it the “universal solvent,” perfect for dissolving salts, sugars, acids, alkalis and even gases such as carbon dioxide, accounting for the fizz in sodas. Such substances are known as hydrophilic (water-loving), precisely because they dissolve so easily in water.

By contrast, fats and oils are classified as hydrophobic, because they do not have electrical charges at their ends. As a result, they are attracted more strongly to one another than to water. To wash such substances from our hands or clothes, we need soaps, which have both hydrophobic and hydrophilic ends that help break them up into tiny droplets that can be carried away by water.

From one state to another

Even more remarkably, water is practically the only substance known to man that, as it cools from its liquid to solid state, actually expands. Virtually every other substance becomes denser as it “freezes,” but thanks to this remarkable property, ice cubes float in our drinks. More importantly for living organisms, lakes and other bodies of water freeze from the top down.

Ice’s remarkably low density is attributable to the fact that water molecules need thermal energy to maintain the random orientations they assume in liquid water. As the temperature decreases, the molecules begin to line up in a regular latticework. To do so, however, the distance between them must increase. As a result, ice is about 9% less dense than liquid water.

The adage that no two snowflakes are alike seems hard to believe until you consider the fact that the patterns in which water molecules freeze vary depending on temperature and humidity. When you add the fact that the average snow crystal contains about 10 quintillion (10 followed by 18 zeroes) water molecules, it is easy to see why the number of possible combinations is unimaginably large.

A continuous cycle

Water is also incredibly dynamic, continuously moving all over the Earth in a cycle of evaporation, condensation, precipitation and runoff back to seas and lakes. The same is true among living organisms, where the hydrogen and oxygen constituents of water are continually combining and recombining through the processes of photosynthesis and respiration.

And while we cannot live without water, it should also be said that we are water producers. Each time we break down a molecule of glucose, we produce six molecules of water, a reaction that takes place in the typical human body about six septillion (6 followed by 24 zeroes) times per day. Even so, we still don’t produce enough water to meet our own needs.

Although droughts in the western US are garnering considerable attention today, it is likely that water will become an even hotter topic over the course of this century. For one thing, only about 3% of the Earth’s water is fresh water, the other 97% being found in the oceans. And about 70% of this fresh water is found in glaciers and the ice caps of Antarctica.

As a result, even though the Earth holds enough water to make a sphere about 860 miles in diameter, only a tiny percentage of this water is easily accessible to human beings, and increasing shortages loom in the future. Some scientists have predicted that, as some point in the 21st century, fresh water will become a more valuable commodity than petroleum.

A saying often misattributed to Albert Einstein claims there are two ways to lead a life. The first is as though nothing is a miracle, and the second is as though everything is a miracle. Water is entirely natural, hugely abundant and so necessary to life that our cells are bathed in it. Yet it is also so remarkable that, as a physician and scientist, I regard it as little short of miraculous.

Richard Gunderman, Chancellor’s Professor of Medicine, Liberal Arts, and Philanthropy, Indiana University-Purdue University Indianapolis

This article was originally published on The Conversation. Read the original article.

Nobel Prize in Chemistry Awarded for Work on Natural DNA Repair

Benjamin Burke, University of Hull

The Nobel Prize in Chemistry for 2015 has been awarded jointly to Sweden’s Tomas Lindahl, USA’s Paul Modrich and Turkish-born Aziz Sancar for their discoveries in the field of natural DNA repair.

Natural DNA repair is necessary for our survival. Every day, damage occurs to our DNA, whether from external factors such as UV light, smoking, radiation or carcinogens or from the natural mistakes that happen continuously in replication of such large amount of code. If these mistakes were not repaired the DNA would decay into chaos – a word not usually a good sign for successful biology.

Lindahl, Modrich and Sangar beat off strong competition from the team behind the genome editing technique CRISPR/CAS9 which many had been considered the strongest contender in the area of molecular biology.

Tomas Lindahl: Challenging the early thinking that DNA is stable, Lindahl who currently works at the Francis Crick Institute and Clare Hall Laboratory in the UK showed that mistakes and problems occur much more often than is possible for life to develop on Earth without repair mechanisms.

He then went on to discover one of these mechanisms, base-excision repair, which removes incorrect bases from the genome and replaces it with the correct one (see video below).

Base-excision repair

Paul Modrich:Working closely with Matthew Meselson from Harvard University, Modrich, now at Duke University in the USA, was interested in DNA signalling and repair. They noticed that mismatched DNA (for example adenine (A) being paired with cytosine ( C ) instead of thymine (T)), which can happen during DNA replication and recombination, can be naturally repaired by a mechanism called “DNA mismatch repair”.

This is triggered when a specific signalling unit, a so called “methyl group” (consisting of three hydrogen atoms bonded to a carbon atom) is not present. These methyl groups act as signposts, helping a particular restriction enzyme to come and cut the DNA strand at the correct location to repair it.

Aziz Sancar: Sancar’s story is a screenwriter’s dream. He was a trained and practising physician who was so interested in biochemistry that he decided to retrain. He was forced into a technician job at Yale University after being unable to secure a postdoctoral research position. While at Yale, he discovered the mechanism by which the enzyme exinuclease finds the UV-damaged DNA and cuts the strand, allowing it to be replaced with non-damaged bases by DNA polymerase.

The discovery of the mechanism, which he called “Nucleotide Excision Repair”, led to a job offer of an associate professorship at the University of North Carolina, where he remains today. Aziz Sancar is the first Turkish winner of a Nobel Prize.

Potential for cancer treatment

These discoveries are hugely important as they deepen our understanding of how we function at a basic biochemical level. Understanding of these mechanisms is essential in the development of new treatment types for an endless number of diseases which have an effect on human DNA.

This certainly applies to cancer treatments, because many anti-cancer drugs actually damage DNA. So when developing a new drug, it is crucially important to know whether cancer cells can repair these damages.

When announcing the prize, Claes Gustafsson, a member of the Nobel assembly, commented that there are now drugs being developed based on knowledge of cancer cells that have a defect repair system. By learning from this, they are trying to find ways to actually inhibit repair in cancer cells to be able to destroy them. “This is a very interesting concept that is currently being developed and I think there are a number of different pharmaceutical industries that are currently looking into this,” he said.

Controversy?

As usual, the Nobel Prize committee is never far from controversy. The award of the Nobel Prize in Chemistry to scientists working in molecular biology may cause many chemists to question the decision, especially as it seems to be happening more and more.

But you can also look at it in the opposite way and actually celebrate the fact that chemistry has gone straight to the heart of so many scientific fields. If we want to deliver on Alfred Nobel’s will to bestow “prizes to those who… have conferred the greatest benefit on mankind” then it is certainly right that we’re looking at all the applications of chemistry.

It also can’t be left unsaid that the tradition of under-representation of women in the Nobel Prize for Chemistry unfortunately continues, with only four winners since 1901.

Benjamin Burke, Molecular Imaging Post-Doctoral Research Assistant, University of Hull

This article was originally published on The Conversation. Read the original article.

Featured Photo Credit: Reuters/Fredrik Sandberg/TT News

When it Comes to Your Smartphone’s Battery Life, You May Be Doing it All Wrong

We all want our smartphones to be charged up so they don’t die at some inopportune moment, but that concern may be driving you to stress your phone’s battery out and shorten its life. We found a super-informative article on Tech Insider that explains why it’s a bad idea to keep your phone charged to 100% all the time:

Many of us have an ingrained notion that charging our smartphones in small bursts will cause long-term damage to their batteries, and that it’s better to charge them when they’re close to dead.

But we couldn’t be more wrong.

If fact, a site from battery company Cadex called Battery University details how the lithium-ion batteries in our smartphones are sensitive to their own versions of “stress.” And, like for humans, extended stress could be damaging your smartphone battery’s long-term lifespan.

If you want to keep your smartphone battery in top condition and go about your day without worrying about battery life, you need to change a few things.

To treat your phone’s battery right and give it a long life, the article makes these four recommendations:

Unplug it when it’s fully charged: “…leaving your phone plugged in when it’s fully charged, like you might overnight, is bad for the battery in the long run. Once your smartphone has reached 100% charge, it gets “trickle charges” to keep it at 100% while plugged in. It keeps the battery in a high-stress, high-tension state, which wears down the chemistry within.”
Try not to charge it to 100%: “According to Battery University, ‘Li-ion does not need to be fully charged, nor is it desirable to do so. In fact, it is better not to fully charge, because a high voltage stresses the battery’ and wears it away in the long run.” So give your battery a break and just plug it in when you can throughout the day.
Plug it in whenever you can: “Charging your phone when it loses 10% of its charge would be the best-case scenario, according to Battery University. Obviously, that’s not practical for most people, so just plug in your smartphone whenever you can. It’s fine to plug and unplug it multiple times a day.”
Keep your phone cool: If your phone gets hot when you charge it and you have a case on it, then you should remove the case when charging. If you’re out in the sun, keep your phone covered so it doesn’t get hot.

Follow those four basic recommendations and your battery should have a longer life which will keep it from getting to a point that it discharges too fast to even be useful. Check out the great article over on the Tech Insider website for additional details and tips.

Source: TechInsider.io – “You’ve been charging your smartphone wrong“

Feature Photo Credit: r. nial bradshaw/Flickr

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That Purple Haze in the Windows of Some Boston Brownstones Explained

If you find yourself walking through the Beacon Hill neighborhood of Boston, you may notice something beautifully strange about some of the windows in the Brownstones there: they are purple! The reason for this goes back to the manufacturing of the glass in the mid-1800s when a mistake made by a European glass manufacturer caused the windows that were cryistal clear when they were delivered to turn purple over time.

A fun article on the Boston Magazine website goes on to explain:

The purple windows, known as Lavenders, are typically found in buildings from the mid-1800s, but these windows don’t incorporate violet hues for stylistic reasons—they were actually a mistake. When the glass for the windows was imported from Europe, it was crystal clear. But after the windows were installed, their exposure to sunlight resulted in a purple tint. The phenomenon was later found to be due to excess manganese oxide in the glass, much to the building owners’ dismay.

Although the chemical flaw was considered a terrible problem back then, in an interesting twist of fate, they have become a status symbol now, according to the article.

To get all the details on the purple-haze windows, see the great article on the Boston Magazine website.

Source: BostonMagazine.com – “Why Some Boston Brownstones Have Purple Windows“

Photo Credit: PHOTO BY KEVIN JARRETT ON FLICKR/CREATIVE COMMONS

Simple, Almost Magical Process Creates Carbon Nanofibers Out of Thin Air

Could this process possibly help to combat climate change? That’s what the lead researcher for this discovery hopes, but regardless of whether it does or not, it’s an incredibly amazing discovery.

We discovered this great article over on the Popular Science website, and it explains:

The process works like this: Solar power goes to two electrodes immersed in a mixture of a molten salt (in this case, lithium carbonate) and lithium oxide. Carbon dioxide from the air interacts with the lithium oxide and produces carbon nanofibers, along with more lithium carbonate and oxygen.

What’s neat about the process is that the lithium carbonate salt solution continually replenishes itself, making a self-contained, continuous generator of carbon fibers that can be used to make a wide range of useful products.

Stuart Licht, the lead researcher, has high hopes that this technology can be deployed at large scales and in fact have a positive effect on the climate by pulling large amounts of CO2 out of the atmosphere. In this video on YouTube, he explains more about that.

But other scientists are, understandably, a bit skeptical. On the next page, we’ll meet one of them…

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