For as long as I can remember, I have been fascinated by the periodic table of elements and how it relates chemical properties to an elements position in the table. Its predictive applications and its ability to teach us some of the principles behind chemical transformations are far-reaching and cannot be overestimated.

At the same time, chemical reactivity is much more nuanced than might be gleaned by looking at the rows and periods of Mendeleevs venerable classification. For example, carbon participates in an overwhelmingly diverse set of chemical transformations, yet relatively little can be concluded about carbons context-dependent reactivity by looking at the periodic table alone. So what is the most appropriate means to classify organic transformations?

The prevailing approach, prescribed by most textbooks, centres on functional groups. This method builds on sameness and categorises reactions based on the expected reactivity of atoms in particular environments. But this classification is not optimally conducive to predicting reaction outcomes and establishing the mechanism by which they proceed. While modern theoretical methods based on quantum mechanics are demonstrably appropriate at suggesting detailed ab initio explanations to countless molecular-level phenomena, there might be benefits to a simple structure-driven formalism that builds on reactivitys foundation: the driving force that is needed to run energetically uphill steps. Securing an appropriate match between the driving force and the reactive intermediate that needs to be created or channelled in a particular direction is what chemical reactivity is all about.1

At first, the driving force concept appears straightforward: favoured processes either minimise enthalpy or maximise entropy (or both). But the driving force is anything but an easy concept to understand. Try asking a colleague about how many types of driving forces they know. It is not a simple question. The usual suspects might include strain release, formation of strong bonds and the like, but the answer will be dwarfed by the overwhelming number of documented chemical transformations and their reasons to exist. Even if we had an exhaustive list of all driving forces imaginable, their actual utility would be limited. This is because, in order to benefit from a driving force, one first needs to cross a kinetic barrier. This is why, despite its universal appeal, driving force remains one of the most intangible and abstract concepts in chemistry. While the notion of the driving force is being used and misused all the time, it is not always possible to apply this concept to address chemistry challenges in a logical way.

Try asking a colleague about how many types of driving forces they know

What could help to rationalise chemical reactivity would be to categorise the known driving forces and uphill steps for comparative purposes. One particular embodiment of this way of thinking does exist. In electrochemistry, standard electrode potentials help to find productive combinations of reductants and oxidants based on thermodynamic arguments from electrochemical half-reactions. These numerical values show how easy or difficult it is for a given species to undergo electron transfer. While the experimentally measured and tabulated values for electrode potentials are useful, they are limited to electron transfer processes that involve charged intermediates on electrode surfaces. What if instead of electrode potential, we consider the broader concept of chemical potential and apply it to mechanism-driven organic chemistry? This sounds appealing but, in practice, chemical potential has not been meaningful for practitioners of organic chemistry because it is not apparent how to apply it in rationalising reactivity.

The prevailing approach, prescribed by most textbooks, centres on functional groups. But this classification is not optimally conducive to predicting reaction outcomes and establishing the mechanism by which they proceed. While modern theoretical methods based on quantum mechanics can suggest detailed ab initio explanations to countless molecular-level phenomena, there might be benefits to a simple structure-driven formalism that builds on reactivitys foundation: the driving force that is needed to run energetically uphill steps. Securing an appropriate match between the driving force and the reactive intermediate that needs to be created is what chemical reactivity is all about.1

At first, the driving force concept appears straightforward: favoured processes either minimise enthalpy or maximise entropy (or both). But the driving force is anything but an easy concept to understand. Try asking a colleague about how many types of driving forces they know. The usual suspects might include strain release, formation of strong bonds and the like, but the answer will be dwarfed by the overwhelming number of documented chemical transformations and their reasons to exist. Even if we had an exhaustive list of all driving forces imaginable, their actual utility would be limited. This is because, in order to benefit from a driving force, one first needs to cross a kinetic barrier.

What could help to rationalise chemical reactivity would be to categorise the known driving forces and uphill steps for comparative purposes. One particular embodiment of this way of thinking already exists. In electrochemistry, standard electrode potentials help to find productive combinations of reductants and oxidants based on thermodynamic arguments from electrochemical half-reactions. These numerical values show how easy or difficult it is for a given species to undergo electron transfer. While the experimentally measured and tabulated values for electrode potentials are useful, they are limited to electron transfer processes that involve charged intermediates on electrode surfaces. What if instead of electrode potential, we consider the broader concept of chemical potential and apply it to mechanism-driven organic chemistry? This sounds appealing but, in practice, chemical potential has not been meaningful for practitioners of organic chemistry because it is not apparent how to rationalise reactivity using this concept.

What is lacking is a classification of available driving forces and their matches with appropriate uphill steps. A particularly attractive proposition would be to find new and previously underappreciated correspondence between endergonic and exergonic elementary reactions. I propose that we consider each endergonic or exergonic step as a synthetic half-reaction (SHR), similar to electrochemical half-reactions. SHRs can then be linked if they have matching higher-energy states, corresponding to ionic and radical intermediates or out-of-equilibrium conformations that help drive reactions. This builds on a reasonable assumption that the energetic benefits of the driving force must operate in the area of the molecule where chemical heavy lifting causes a chemical transformation. I refer to such instances as spatioenergetic matches.2

It stands to reason that only some matches between synthetic half-reactions would be productive or interesting. While many of these combinations might correspond to already established processes, I suspect that there will be instances that have not received prior attention and experimental verification. The possibility to find new reactions by understanding how half-reactions can be spatioenergetically matched with one other is an enticing proposition. On a pedagogical level, this way of thinking might encourage new ideas and expand students horizons away from the driving force usual suspects.

There is presently no way to comprehensively evaluate productive combinations of driving forces and their cognate uphill steps. Indeed, search engines such as Reaxys and SciFinder do not offer an opportunity to evaluate higher energy states. I propose creating a continually expanding knowledge base of SHRs. The time is right for the emergence of a system that will allow intuitive understanding of the relationships
between reactive intermediates and other high energy states. This knowledge base should stand as a worthy complement to the periodic table of elements.

While the half-reaction idea should be intuitively clear to any organic chemist, there is presently no way to comprehensively evaluate productive combinations of driving forces and their cognate uphill steps. Indeed, search engines such as Reaxys and SciFinder do not offer an opportunity to evaluate higher energy states. I propose creating a continually expanding knowledge base of SHRs. The time is right for the emergence of a system that will allow understanding of the relationships between reactive intermediates and other high energy states. This knowledge base should stand as a worthy complement to the periodic table of elements.

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Space, energy and synthetic half-reactions | Opinion - Chemistry World

In a league where every movement is tracked and every statistic is measured, chemistry remains the rare, unquantifiable variable that dictates NBA wins and losses.

The intrigue: Fostering NBA chemistry has become increasingly difficult now that players change teams so often. But nothing has ever impacted chemistry-building quite like the pandemic. The question is: has it helped or hurt?

Consider this: Due to the short offseason, rookie Anthony Edwards made his NBA debut just 33 days after being drafted No. 1 overall by the Timberwolves.

The bottom line: So, amid the strangest season of their lives, have NBA teams come together or drifted apart? The truth is, we'll never know.

I reached out to Mavericks owner Mark Cuban to get his take on NBA chemistry and how it has been affected by the pandemic.

How important is chemistry in the modern NBA?

How do you think the pandemic has impacted chemistry this season?

What do the Mavericks do to foster chemistry? Has that been impacted?

Is basketball chemistry similar to chemistry in any workplace?

More here:
How the COVID-19 pandemic has affected NBA team chemistry - Axios

ExoMars observing water in the Martian atmosphere. Credit: ESA

Sea salt embedded in the dusty surface of Mars and lofted into the planets atmosphere has led to the discovery of hydrogen chloride the first time the ESA-Roscosmos ExoMars Trace Gas Orbiter has detected a new gas. The spacecraft is also providing new information about how Mars is losing its water.

A major quest in Mars exploration is hunting for atmospheric gases linked to biological or geological activity, as well as understanding the past and present water inventory of the planet, to determine if Mars could ever have been habitable and if any water reservoirs could be accessible for future human exploration. Two new results from the ExoMars team published today in Science Advances unveil an entirely new class of chemistry and provide further insights into seasonal changes and surface-atmosphere interactions as driving forces behind the new observations.

Weve discovered hydrogen chloride for the first time on Mars. This is the first detection of a halogen gas in the atmosphere of Mars, and represents a new chemical cycle to understand, says Kevin Olsen from the University of Oxford, UK, one of the lead scientists of the discovery.

Hydrogen chloride gas, or HCl, comprises a hydrogen and chlorine atom. Mars scientists were always on the look-out for chlorine- or sulfur-based gases because they are possible indicators of volcanic activity. But the nature of the hydrogen chloride observations the fact that it was detected in very distant locations at the same time, and the lack of other gases that would be expected from volcanic activity points to a different source. That is, the discovery suggests an entirely new surface-atmosphere interaction driven by the dust seasons on Mars that had not previously been explored.

In a process very similar to that seen on Earth, salts in the form of sodium chloride remnants of evaporated oceans and embedded in the dusty surface of Mars are lifted into the atmosphere by winds. Sunlight warms the atmosphere causing dust, together with water vapor released from ice caps, to rise. The salty dust reacts with atmospheric water to release chlorine, which itself then reacts with molecules containing hydrogen to create hydrogen chloride. Further reactions could see the chlorine or hydrochloric acid-rich dust return to the surface, perhaps as perchlorates, a class of salt made of oxygen and chlorine.

You need water vapor to free chlorine and you need the by-products of water hydrogen to form hydrogen chloride. Water is critical in this chemistry, says Kevin. We also observe a correlation to dust: we see more hydrogen chloride when dust activity ramps up, a process linked to the seasonal heating of the southern hemisphere.

Data plot showing measurements of hydrogen chloride in the atmosphere of Mars, as collected by the Atmospheric Chemistry Suite (ACS) onboard the ESA-Roscosmos ExoMars Trace Gas orbiter. The detections were also confirmed by the complementary instrument, Nadir and Occultation for MArs Discovery (NOMAD). The global dust storm of 2018 is indicated by the brown/orange gradient. The plot shows the locations of the measurements over time (solar longitude) and planetary latitude. Credit: Korablev et al (2021)

The team first spotted the gas during the global dust storm in 2018, observing it appear simultaneously in both northern and southern hemispheres, and witnessed its surprisingly quick disappearance again at the end of the seasonal dusty period. They are already looking into the data collected during the following dust season and see the HCl rising again.

It is incredibly rewarding to see our sensitive instruments detecting a never-before-seen gas in the atmosphere of Mars, says Oleg Korablev, principal investigator of the Atmospheric Chemistry Suite instrument that made the discovery. Our analysis links the generation and decline of the hydrogen chloride gas to the surface of Mars.

Extensive laboratory testing and new global atmospheric simulations will be needed to better understand the chlorine-based surface-atmosphere interaction, together with continued observations at Mars to confirm that the rise and fall of HCl is driven by the southern hemisphere summer.

The discovery of the first new trace gas in the atmosphere of Mars is a major milestone for the Trace Gas Orbiter mission, says Hkan Svedhem, ESAs ExoMars Trace Gas Orbiter project scientist. This is the first new class of gas discovered since the claimed observation of methane by ESAs Mars Express in 2004, which motivated the search for other organic molecules and ultimately culminated in the development of the Trace Gas Orbiter mission, for which detecting new gases is a primary goal.

As well as new gases, the Trace Gas Orbiter is refining our understanding of how Mars lost its water a process that is also linked to seasonal changes.

Liquid water is once thought to have flowed across the surface of Mars as evidenced in the numerous examples of ancient dried out valleys and river channels. Today, it is mostly locked up in the ice caps and buried underground. Mars is still leaking water today, in the form of hydrogen and oxygen escaping from the atmosphere.

Understanding the interplay of potential water-bearing reservoirs and their seasonal and long-term behavior is key to understanding the evolution of the climate of Mars. This can be done through the study of water vapour and semi-heavy water (where one hydrogen atom is replaced by a deuterium atom,a form of hydrogen with an additional neutron).

The deuterium to hydrogen ratio, D/H, is our chronometer a powerful metric that tells us about the history of water on Mars, and how water loss evolved over time. Thanks to the ExoMars Trace Gas Orbiter, we can now better understand and calibrate this chronometer and test for potential new reservoirs of water on Mars, says Geronimo Villanueva of NASAs Goddard Space Flight Center and lead author of the new result.

With the Trace Gas Orbiter we can watch the path of the water isotopologues as they rise up into the atmosphere with a level of detail not possible before. Previous measurements only provided the average over the depth of the whole atmosphere. It is like we only had a 2D view before, now we can explore the atmosphere in 3D, says Ann Carine Vandaele, principal investigator of the Nadir and Occultation for MArs Discovery (NOMAD) instrument that was used for this investigation.

The ESA-Roscosmos ExoMars Trace Gas Orbiter studies water vapour and its components as it rises through the atmosphere and out into space. By looking specifically at the ratio of hydrogen to its heavier counterpart deuterium, the evolution of water loss over time can be traced. Credit: ESA

The new measurements reveal dramatic variability in D/H with altitude and season as the water rises from its original location.Interestingly, the data show that once water is fully vapourised, it mostly displays a common large enrichment in semi-heavy water, and a D/H ratio six times greater than Earths across all reservoirs on Mars, confirming that large amounts of water have been lost over time, says Giuliano Liuzzi of American University and NASAs Goddard Space Flight Center and one of the lead scientists of the investigation.

Seasonal variability of water (left) and D/H (right) for the northern (top) and southern (bottom) hemispheres, as determined by the Nadir and Occultation for MArs Discovery (NOMAD) instrument onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter.Water is observed to reach high altitudes of greater than 80 km during regional and global dust storms, and at the onset of southern summer (labeled aspirator from the latin word to aspire, or rise/climb up). Colder temperatures at the poles and in the middle atmosphere lead to fractionation of water and an apparent decrease of the D/H. Yet, when water is fully vapourised, it displays a strong enrichment of six times that of Earths oceans, confirming that large amounts of water have been lost to spa
ce over time.Credit: Villanueva et al (2021)

ExoMars data collected between April 2018 and April 2019 also showed three instances that accelerated water loss from the atmosphere: the global dust storm of 2018, a short but intense regional storm in January 2019, and water release from the south polar ice cap during summer months linked to seasonal change. Of particular note is a plume of rising water vapor during southern summer that would potentially inject water into the upper atmosphere on a seasonal and yearly basis.

The graphic shows a simple representation (not to scale) of the three observing modes that will be used by the ExoMars Trace Gas Orbiter. In nadir mode (left) the spacecraft looks directly at the sunlight reflected from the surface and atmosphere of Mars. In limb mode (centre) it looks across the martian horizon at emission from the atmosphere. In solar occultation mode (right), the instruments point through the atmosphere toward the Sun and observe how different atmospheric ingredients absorb the Suns light. Credit: ESA/ATG medialab

Future coordinated observations with other spacecraft including NASAs MAVEN, which focuses on the upper atmosphere, will provide complementary insights to the evolution of water over the martian year.

The changing seasons on Mars, and in particular the relatively hot summer in the southern hemisphere seems to be the driving force behind our new observations such as the enhanced atmospheric water loss and the dust activity linked to the detection of hydrogen chloride, that we see in the two latest studies, adds Hkan. Trace Gas Orbiter observations are enabling us to explore the martian atmosphere like never before.

References:

Transient HCl in the atmosphere of Mars by Oleg Korablev, Kevin S. Olsen, Alexander Trokhimovskiy, Franck Lefvre, Franck Montmessin, Anna A. Fedorova, Michael J. Toplis, Juan Alday, Denis A. Belyaev, Andrey Patrakeev, Nikolay I. Ignatiev, Alexey V. Shakun, Alexey V. Grigoriev, Lucio Baggio, Irbah Abdenour, Gaetan Lacombe, Yury S. Ivanov, Shohei Aoki, Ian R. Thomas, Frank Daerden, Bojan Ristic, Justin T. Erwin, Manish Patel, Giancarlo Bellucci, Jose-Juan Lopez-Moreno and Ann C. Vandaele, 10 February 2021, Science Advances.DOI: 10.1126/sciadv.abe4386

Water heavily fractionated as it ascends on Mars as revealed by ExoMars/NOMAD by Geronimo L. Villanueva, Giuliano Liuzzi, Matteo M. J. Crismani, Shohei Aoki, Ann Carine Vandaele, Frank Daerden, Michael D. Smith, Michael J. Mumma, Elise W. Knutsen, Lori Neary, Sebastien Viscardy, Ian R. Thomas, Miguel Angel Lopez-Valverde, Bojan Ristic, Manish R. Patel, James A. Holmes, Giancarlo Bellucci, Jose Juan Lopez-Moreno and NOMAD team, 10 February 2021, Science Advances.DOI: 10.1126/sciadv.abc8843

The papers are based on data collected by the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter.

A forthcoming paper Seasonal reappearance of HCl in the atmosphere of Mars during the Mars year 35 dusty season by K. Olsen et al has been accepted for publication in Astronomy & Astrophysics.

Read the original here:
A New Chemistry: ExoMars Orbiter Discovers New Gas and Traces Water Loss on Mars - SciTechDaily

It has been nearly a month since the Nets pulled off the megadeal for James Harden, but the team still hasnt been able to fully realize its Big 3.

From injuries to quarantine to personal leave, Harden, Kevin Durant and Kyrie Irving have averaged just over a start per week together. They havent played together since an impressive Feb. 2 win over the Clippers, but the trio hopes to be reunited Saturday, when Durant is expected to make his return to Golden State.

The terrific trio have looked good on the court together (theyre 4-1 as starters), but the Nets are waiting for the day when they look truly great like the superteam they bargained for.

[Harden] is in a much better shape than when he got here; hell probably get in better condition as the season goes, as well, coach Steve Nash said. Its funny. [Its been] four weeks already, Kevin and Kai and James have played 5 games, if you include the Raptors game, together.

So its kind of astonishing to have him for a month and theyve only played five [starts] together, or 5 games. So lots of time [left], but weve got to get going here and get all three of them on the court and our complete roster going, and try to build and continually improve even if its small margins, small improvements. If we keep getting better, weve got a chance to be a special team.

The Nets agreed to the Harden deal Jan. 13, and he debuted three days later. But at that point Irving was still out following a personal leave and the ensuing quarantine.

Then they lost Durant to his second contact-tracing incident of the season, which forced another weeklong quarantine. Hes expected back when the Nets tip off a five-game Western swing with his return to the Bay Area for Saturdays game.

He gives the team confidence. Hes obviously one of the best players in the history of the game, but for our team, he gives us confidence. The guys look to him, Nash said. Whether he has the ball in his hands or doesnt, hes an important part of what were trying to do.

The Nets are 3-0 with the Big 3 starting along with Joe Harris and DeAndre Jordan. Theyre 1-0 with the trio starting with Harris and stretch-5 Jeff Green, and 0-1 using a big lineup with both Jordan and Green.

They suffered a disjointed loss to the Raptors when Durant was scratched before tipoff for contact tracing, then logged 19 minutes and finally was yanked off the court when the person he had been in contact with tested positive for COVID-19.

The Big 3 have logged 164:38 together over six games, with the Nets a plus-18 in that stretch. But theyve lived up to their billing as fourth-quarter closers.

The Nets are a stellar plus-24 in the 41 minutes Durant, Harden and Irving have logged together over five games. Their net rating is 28.9, and their offensive rating is 148.2, the best of any trio that has played at least 40 minutes together.

Still, they can get better as Harden not only gets in better shape, but also gets more aggressive both in communicating defensively and asserting himself while Durant and Irving are on court.

Thats my job. I have to do a better job of just communicating and maybe watching more film, communicating more on where guys should be, just using my voice more so guys can be in their spots, Harden said. So, as one of the leaders of this team, Ive got to do a better job communicating: And I will be.

Harden had a couple of animated talks with Jordan during Tuesdays loss in Detroit, and the center responded with a double-double in Wednesdays win over the Pacers at Barclays Center. When Harden harnesses the same aggression playing with Durant and Irving as he does on the second unit, itll unlock the Big 3s potential.

Ultimately, we want to get to a place where all three are playing basketball together offensively instead of taking turns. In theory, he should be just as aggressive when theyre in the lineup, Nash said. An aggressive James is the way we want him to play.

This trip offers the Nets and the rest of the NBA a chance to see that.

Thats going to help us on the floor, being able to just build that chemistry with guys, Jordan said. And obviously once we get Kevin back from his timeout, well incorporate. This road trip will be good for us.

Read more here:
Nets hoping Big 3 finally will get chance to build chemistry - New York Post

Saying a loved one has a heart of gold is high praise. A compliment of Shakespearean origins, heart of gold signifies the person is kind and honourable. Similarly, deeming someone as good as goldmeans they are genuine, reliable and well-behaved. Trade the gold in both idioms for arsenic, lead or thallium, and praise becomes poison. The toxicity of these other semi-metals and metals is so well known that heart of lead or as good as arsenic would be widely recognised as grievous insults. For those persons held close to our hearts, gold-themed descriptions bestow the glittering qualities of the metal to the individual and relationship splendour, stability and safety.

Bulk gold is considered safe because it is one of the least reactive metals.(Nano gold is weird.1 The fate and toxicity of gold nanoparticles are still challenging questions to answer.) Gold metal is impervious to various forms of chemical corruption that would consume lesser metals, earning its noble metal moniker and making it ideal for currency. For its shine and statement of status, pure gold has adorned weaponry throughout history for style, rather than substance. Metallic gold, for all its superior qualities, is too soft for heavy combat.2,3

Death by gold has made a splash in fiction, but many fans know this is just flashy mayhem.Consider the death of Viserys Targaryenin HBOs Game of Thrones. Viserys pushed his sister Daenerys and her husband Khal Drogo too far, even petulantly demanding a crown. Drogo happily and brutally gave Viserys a crown by pouring molten gold (which has a temperature of1064Cor more) upon his head. Viserys death was gilded, but many melted metals would have given the same gruesome outcome.

Far less gory, but just as dramatic, was the demise of Bond girl Jill Masterson in Goldfinger. Painted head to toe in gold, Masterson allegedly died due to skin suffocation a cause of death as ludicrousas Bonds double entendres. Bulk gold is considered so safe its been used as a dental prosthetic and restorativefor over 4000 years.4,5 People even eat pure gold with no ill effects like the worlds most expensive hamburger that was wrapped in gold leaf, or similarly adorned sparkling sushi and doughnuts. But just as all that glitters is not gold, not all gold is harmless. Bulk gold is considered a safe bet,6but all bets are off with gold salts.

The pharmacology and toxicology of gold(i) compounds is markedly different from metallic gold.5 This can be a boon or bane. Select gold(i) salts were literally the gold standard of treatment for rheumatoid arthritis,79with their therapeutic activity likely due to several mechanisms. Chrysotherapy, so named because gold is called chrysos in Greek, must be carefully managed. The toxicity of medicinally used gold salts follows along the lines of classic heavy metal poisoning, including the hallmark symptoms of abdominal pain, nausea and vomiting. Gold salts affect a number of bodily systems and sites including skin, mucosa, kidney, blood, bone marrow, lung, nervous system and the liver. Deaths are rare, though they have been documented in the literature for several decades.810None appear to be the result of someone poisoning the patient. To find a documented case of criminal chrysotherapy, I had to take a dramatic turn.

In an episode of the American medical TV drama House, an apparently happily married couple are treated by Dr House and his team, the husband suffering from an array of ailments. The wifes displays of devotion turn out to be masking discontent. House proves through the use of the stannous chloride colour testfor gold11 that the wife has been poisoning her spouse. She is literally caught purple handed, as the test produces a pigment called purple of Cassius.12

Houses trick of coating his hands in stannous chloride test solution and clasping the wifes is not recommended for repeating, as this solution is typically 1020% weight per weight hydrochloric acid. House names the compound responsible to be the arthritis drug gold(i) sodium thiomalate (brand name Myochrysine), quipping that either the wifes fingers are worth their weight in gold or she has been sprinkling the drug on her husbands cereal.

Given the diabolical genius of this poisoning plot, you will be happy to know that getting ones nefarious hands on gold(i) sodium thiomalate might be more difficult than prospecting for gold. Like mostgold salts-based drugs, it is administered by intramuscular injection, and doses are stored at a healthcare site and administered by a healthcare professional by prescription. Perhaps most comforting to readers is that I found no real-life murderous plots featuring chrysotherapy gold salts. Lets hope users of these compounds remain as good as gold.

1 M B Cortie,Gold Bull., 2004,37, 12 (DOI: 10.1007/BF03215512)

2 J Browne,Seven Elements that have Changed the World: Iron, Carbon, Gold, Silver, Uranium, Titanium, Silicon. Weidenfeld & Nicolson, 2013

3 C H Fulton,Principles of Metallurgy: An Introduction to the Metallurgy of the Metals. McGraw-Hill Book Company, 1910

4 H Knospet al,Gold Bull., 2003,36, 93 (DOI: 10.1007/BF03215496)

5 B Merchant,Biologicals, 1998,26, 49 (DOI: 10.1006/biol.1997.0123)

6 C J Murphyet al,Acc. Chem. Res., 2008,41, 1721 (DOI: 10.1021/ar800035u)

7 S L Best and P J Sadler,Gold Bull., 1996,29, 87 (DOI: 10.1007/BF03214741)

8 S Ueda and G A Porter,Gold salts, D-penicillamine and allopurinol. In Clinical Nephrotoxins: Renal Injury from Drugs and Chemicals (eds. M E De Broeet al). Springer US, 2008

9 A Balfourieret al,Proc. Natl. Acad. Sci USA, 2020,117, 22639 (DOI: 10.1073/pnas.2007285117)

10 J G Macleod,Ann. Rheum. Dis., 1948,7, 143 (ncbi.nlm.nih.gov/pmc/articles/PMC1030591)

11 C Fink and G Putnam,Ind. Eng. Chem. Anal. Ed., 1942,14, 468 (DOI: 10.1021/i560106a008)

12 F Habashi,Eur. Chem. Bull., 2016, 5, 416 (DOI: 10.17628/ecb.2016.5.416-419)

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Heart of gold | Opinion - Chemistry World

FREMONT, Calif., Feb. 9, 2021 /PRNewswire/ -- Thermo Fisher Scientific, the world leader in serving science, today announced a partnership with Mindray, a leading global developer, manufacturer and supplier of medical devices, to make available to customers two clinical chemistry analyzers in the United States (U.S.) and Canada for drug screening in clinical and drug court laboratories.

"Systematically and reliably testing for drugs of abuse is key to helping addicted individuals rehabilitate, ensuring prescribed drugs are not abused and ultimately, helping to combat this crisis," said Stefan Wolf, president of the clinical diagnostics business at Thermo Fisher Scientific. "Through this exclusive partnership with Mindray we are able to address the needs of our customers in commercial labs, hospitals and the criminal justice field. Now we can better cater to the needs of those laboratories seeking to expand or increase their testing volumes, and laboratories working to consolidate and centralize their testing sites with these two medium- to high-throughput instruments."

To provide access to drug testing, Thermo Fisher and Mindray have entered into an agreement to offer the FDA-cleared and Health CanadaapprovedBS-480 (400 tests/hour) and BA-800M (800 tests/hour) analyzers to toxicology labs. Thermo Fisher will also provide an extensive menu of wet labvalidated Thermo Scientific DRI and CEDIA drugs of abuse immunoassay reagents with the instruments to enable the screening of urine samples for the presence of a given drug or a class of drugs.

Taken together, the world-class DRI and CEDIA drugs of abuse immunoassay reagents, validated on Mindray's instruments, bring a combination of performance and reliability from a single source in a cost-effective, plug-and-play solution. The solution streamlines the drug screening workflow and automates it to reduce risk of human error. The instruments also come with onboard software that has many advanced features, including sample/reagent probe collision protection, sample aggregate detection and a five-minute daily push-button self-service maintenance program.

Thermo Fisher began distributing, installing, training and servicing Mindray BS-480 and BA-800M instruments in the U.S. and Canada last month.

About Thermo Fisher Scientific

Thermo Fisher Scientific Inc. is the world leader in serving science, with annual revenue exceeding $30 billion. Our Mission is to enable our customers to make the world healthier, cleaner and safer. Whether our customers are accelerating life sciences research, solving complex analytical challenges, improving patient diagnostics and therapies or increasing productivity in their laboratories, we are here to support them. Our global team of more than 80,000 colleagues delivers an unrivaled combination of innovative technologies, purchasing convenience and pharmaceutical services through our industry-leading brands, including Thermo Scientific, Applied Biosystems, Invitrogen, Fisher Scientific, Unity Lab Services and Patheon. For more information, please visit http://www.thermofisher.com.

Media Contact Information: Kathy Ruzich 510-979-5157 [emailprotected]

Secondary Contact Information: Romeo Goia 317-908-8978 [emailprotected]

SOURCE Thermo Fisher Scientific

http://www.thermofisher.com

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Thermo Fisher Scientific Partners with Mindray on Clinical Chemistry Analyzers for use with Drugs of Abuse Immunoassays - PRNewswire

How have you managed to keep your research group motivated during the pandemic?

In Japan, we actually didnt have a serious long-term lockdown, so we were able to work in the lab but with limited members in two groups. We were therefore able to maintain a sufficient level of research, so that was good. I worked from home mostly, and we used Slack to communicate as a group. Through this channel, members of the group were able to share some of their skills for others to learn from. Some members are experienced in coding, other members are experienced in the use of graphics software, and others are able to share their skills in carrying out DFT calculations. Each Slack channel was used as a learning tool tutorials were given to help other members learn a new skill, and this provided an opportunity for questions to be asked on each topic. This was completely spontaneous, but we were all able to learn a lot from this.

We also used this time to connect with other groups from around the world. It was a great opportunity to discuss our science and exchange results, and is something that Id like to continue to do in the future.

I enjoy research that explores the structural transformations of assembled systems, and that demonstrates how systems can adapt to their environment and any external stimuli. Nature can do this because of evolution of course, with millions of years being spent adapting systems to a particular environment. For materials science researchers, its much more difficult.

I have several favourite papers that represent this kind of research. One of these, a paper published in Nature by Professor Matthew Rosseinsky, demonstrated the adaptable porosity of peptide-based metal organic frameworks (MOFs), which were able to form nine different conformations depending on the guest molecule. The authors used dihedral principle component analysis to correlate the movement of the dihedral angle of the peptide to the total structure in order to understand how the structure changed. This was such beautiful work.

Another paper that I would like to highlight, by Professor F. Akif Tezcan (Nature 2018), demonstrates something similar but on a macroscopic scale and based on protein crystals. In this work, the authors were able to use polymers to alter parts of a protein, which enabled them to tune the resulting crystals. Macroscopic expansion of the crystals was demonstrated, whilst maintaining the lateral positon. The vector is therefore the same, but the proximity changes. This work demonstrated such careful control from the molecular to the macroscopic scale.

Becoming a group leader has led to some incredibly exciting moments in my career. On a few occasions, members of my group have come into my office with such a serious expression on their face when presenting data that wasnt expected. They automatically assume that something has gone wrong during the experiment. However, most of these situations are actually quite exciting because unexpected data can come from completely different reactions to what we had expected. This allows us to construct a new story. Unexpected data means that we have to rethink our hypothesis, and through reconstruction, we can carry out new experiments to confirm our results and provide the correct answer. This has happened on a number of occasions, and I always find it incredibly exciting.

From 20072017, I was working as a group leader under the guidance of Professor Susumu Kitagawa, handling one of his sub-groups. In 2017 I became an independent professor, and my group was initially made up of only three members. We therefore had to be selective in which projects we wanted to pursue. That was quite a difficult moment, but I really appreciated the input of my postdoc at that time, Dr Gavin Craig. He was really helpful and worked incredibly hard, as he had to take over quite a lot of projects, and at the same time maintain his own research.

In our first paper in 2015, we demonstrated how we were able to prepare superstructures of flexible metal organic frameworks over multiple length scales. Here, not only were we able to control the molecular structure at the nanoscopic level, but we were also able to control the positioning of the crystals to make hierarchical architectures. From this work, we realised that there was potential to propagate the structure dynamics from the macroscopic to the nanoscopic level. However, we noted that this would be very difficult to do because of the crystallinity of MOFs they become hard materials and can become brittle under mechanical stress.

We then switched to making porous materials with metal organic polyhedra, containing cage molecules, in order to prepare systems with more of a flexible nature, which led to a 2018 publication in Chemical Science that was chosen as a Pick of the Week. Our research in Chemical Science over the past five years therefore tells quite a nice story - by changing the metal material to a cage, we were able to show the first example of flexible metal organic polyhedra. In 2020, we are now working out how we can enable transpropagation of mechanical stress in these kinds of systems, which could lead to a number of interesting applications.

We only publish papers in Chemical Science that present novel and interesting concepts, so I would definitely say that I am proud of them all! If I had to choose one however, it would be our contribution from 2019, which demonstrated the induction of gradients inside porous materials through the application of gravity. We were able to achieve this through a detailed understanding of the assembly process. I really like this concept because, through controlling the gradient, we had the chance to tune the chemical potential, which means that we can initiate the unidirectional transport of molecules. On the mesoscopic level, we are therefore able to the tune the properties of these systems.

I am very happy to say that all of my submissions to Chemical Science have been accepted. I think this is for two reasons: First of all, we only ever submit research that presents a new concept to the journal, but also because I think that Chemical Science is very accepting of new ideas and fundamental research. Other journals are quite picky, and I think care too much about research that will receive citations within the first two years rather than considering the impact that research will have in the long-term. Chemical Science is very good at choosing conceptually novel papers that will really be ground-breaking in the field over the next five to ten years.

My interests lie in translating the level of control that we have in normal macroscopic systems to the corresponding nanoscale systems. In order to do that, we require an understanding of the whole structure and all of the features of the system that we are investigating, from the nano- up to centimetre scale. I also want to further explore the introduction of separate components into these kinds of systems - if we can include more components, we have an opportunity to optimise the properties further

To celebrate the 10th anniversary ofChemical Sciencewe are publishing a number of special birthday issues, to recognise and thank members of our community who have been supporting the journal and publishing inChemical Sciencesince we launched ten years ago.

Explore our collection now.

See the rest here:
Celebrating 10 years of Chemical Science: Demonstrating new ideas and concepts - Royal Society of Chemistry

The Mid-Michigan Section of the American Institute of Chemical Engineers (AIChE) invites the public to a special presentation.

The group is committed to providing a safe and healthy environment for all meeting attendees. In light of the impact of the coronavirus, all meetings will be held virtually until further notice. The next meeting will feature an address by Mary Beth Mulcahy, "Chemical Security: Protecting Chemicals from People," from noon to 1 p.m. on Tuesday, Feb. 16.

Chemical safety aims to prevent an accidental release of hazardous materials or energy, while chemical security addresses the prevention and control of threats that have the potential to result in unauthorized access, loss, theft, misuse, diversion or intentional release of hazardous materials or energy. Stated more simply, chemical safety aims to protect people from chemicals while chemical security aims to protect chemicals from people. Is this seminar, Mulcahy will provide a brief introduction to chemical weapons, introduce basic chemical security concepts, and examine a toxic release described in a U.S. Chemical Safety Board report through a chemical security lens.

Mulcahy is an R&D S&E, systems research and analysis professional in the Global Chemical and Biological Security (GCBS) program and a causal analyst with the Environmental Safety & Health (ES&H) Performance Assurance Occurrence Management team at Sandia National Laboratories. As part of GCBS, Mulcahy works with an interdisciplinary team to engage global partners for the identification and integration of technical solutions in chemical security and safety. Her work with ES&H includes performing casual analysis of safety incidents and near-misses to support Sandia's goal of continual safety learning.

In additional, Mulcahy serves as the editor-in-chief of the American Chemical Society's ACS Chemical Health & Safety journal which focuses on publishing high-quality articles of interest to scientists, EH&S professionals, and non-research personnel who manage or work in areas where chemicals are used or hazardous waste is generated.

Previously, Mulcahy worked for nine years as a chemical incident investigator with the U.S. Chemical Safety Board (CSB), an independent federal agency that determines the root causes of major chemical accidents in the United States. At the CSB, Mulcahy investigated accidents in a variety of settings; a five-worker fatality on an onshore oil rig blowout, a dust explosion at a corn milling facility in Wisconsin that killed five workers and injured 14 others, an 11-fatatilty offshore oil drilling rig (Deepwater Horizon), a 14-fatality ammonium nitrate explosion, a university laboratory, as well as explosions at a food and power plants.

Mulcahy earned her Ph.D. in physical chemistry from the University of Colorado in Boulder. After graduate school, she completed a postdoctoral fellowship funded by the National Science Foundation at the Instituto Balseiro in Bariloche, Argentina, and then spent time doing research for a biotechnology company before joining the CSB.

The lecture qualifies for one continuing education hour. CEH certificates are needed for licensed Professional Engineers to maintain their license and certificates will be provided to interested attendees.

For seminar call-in information, email Pranav Karanjkar at pranav.karanjkar@dow.com.

Read more here:
Mid-Michigan AIChE to host presentation on chemical security Feb. 16 - Midland Daily News

Chemical techniques in India can be traced back all the way to the Indus valley or Harappan civilisation (3rd millennium BCE). Following Acharya Prafulla Chandra Ray (1861-1944), the eminent Indian chemist of the last century and a historian of chemistry, five stages in its development in India can be recognised. They are: (i) the pre-Vedic stage upto 1500 BCE, including the Harappan period, (ii) the Vedic and the Ayurvedic period upto 700 CE, (iii) the transitional period from 700 CE to 1100 CE, (iv) the Tantric period from 700 CE to 1300 CE, and (v) the Iatro-Chemical period from 1300 CE to 1600 CE. The dates cannot be considered definitive.

Metallurgy was intimately linked with chemistry in India. We will discuss Indian metallurgy and metal-working in a later article, focussing our attention on chemical techniques for now. Pre-Harappan Indians were acquainted with the art of making baked or burnt clay pottery as well as painting the same with two or more colours. This implies the construction of open and closed kilns. The pottery of the Harappan culture consisted of mainly wheel-made ware, turned in various shapes, sizes and colours out of the well-levigated alluvium of the Indus.

The colour and other characteristics of the wares depended upon the composition of the clay used and techniques of firing under either oxidising or reducing conditions. The Harappans also experimented with various mortars and cements made of burnt limestone, gypsum and mica, among other components. Finely crushed quartz, once fired, produced faience, a synthetic material; it was then coated with silica (perhaps fused with soda), to which copper oxide was added to give it a shiny turquoise glaze. Faience was then shaped into various ornaments and figurines.

Addition of iron oxide, manganese oxide, etc., resulted in different colours. The Harappan artisans must have had an intimate knowledge of the processing and properties of several naturally occurring chemical substances. The craftsmen were highly skilled in the art of shaping and polishing the precious and semi-precious stones used for the production of beads. In the second stage, Rigveda (earlier than 1500 BCE) mentions many fermented drinks and methods of fermentation, apart from various metals. Soma juice from the stems of the soma plant was highly extolled and considered a divine drink. Madhu and suraa (brewed from barley grain) also find mention.

Curd or fermented milk was an important food item. Cloths were mainly made of wool and the garments were often dyed red, purple or brown. Obviously, the Vedic Indians were acquainted with the art of dyeing with certain natural vegetable colouring matters. A type of pottery, now known as Painted Grey Ware, is associated with the Vedic period. This ceramic is a thin gray deluxe ware, mostly wheel-made, well-burnt, glossy and copiously painted. Later, Northern Black Polished Ware also came into being in the eastern part of the Gangetic plains. Also, plenty of iron objects of the later period have been found throughout India.

Glass beads dating back to the 10th century BCE have been discovered. In the succeeding centuries, the glass industry gained momentum and there were notable feats of excellence, as evidenced by the archeological finds in over 30 sites spread over India. The sites include Taxila in present Pakistan, Hastinapur, Ahichchhatra and Kopia in Uttar Pradesh, Nalanda in Bihar, Ujjain in Madhya Pradesh, Nasik and Nevasa in Maharashtra, Brahmagiri in Karnataka, and Arikamedu in Puducherry. The glass objects include beads of different colours, including gold foil ones, glass vessels in green and blue colours, flasks of agate-banded type, bangles, ear-reels, eye-beads, etc.

There is no doubt that the glassmakers were skilful in controlling the temperature of fusion, moulding, annealing, blotching and gold foiling. The chemical composition of a typical glass specimen from Kopia is as follows: silica 66.6%, alumina 7%, alkalies (Na2O) 21.7%, ferric oxide 1.6%, lime 2.4%, manganese oxide .07%, and traces of titania and magnesia. Kautilyas Arthashaastra (3rd or 4th century BCE), a well-known text of governance and administration, has a lot of information on prevailing chemical practices. Apart from mines and minerals, it discusses the details of precious stones (pearl, ruby, beryl, etc.), and also of the preparation of fermented juices (sugarcane, jaggery, honey, jambu, jackfruit, mango, etc.) and oil extraction.

It also has classifications such as sour fruit juices, liquids, spices, vegetables, etc., based on their chemical practices. The earliest versions of the two great Ayurveda classics, Charaka Samhitaa and Sushruta Samhitaa, may date back to a few centuries before the common era. They give accounts of several minerals, metals, metallic compounds, salts and fermented beverages. More importantly, they discuss the preparation of various alkalis (kshaara). Alkalis are of three types: mild (mridu), caustic (teekshna) and average (madhyama).

They are prepared from some 25 plants that are mentioned in Sushruta Samhitaa. Hot alkaline solutions were used for treating thin sheets of metals like iron, gold or silver before incorporation into drugs. Caustic alkalis were also used for treating surgical instruments. Varahamihiras Brihat-samhitaa (6th century CE) gives detailed information on the preparation of various perfumes and cosmetics. It also gives recipes for the preparation of glutinous material to be applied on the roofs and walls of buildings.

M S Sriram (sriram.physics@gmail.com)Theoretical Physicist & President,Prof. K.V. Sarma Research Foundation

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Chemistry in ancient India, from Harappan to Ayurvedic period - The New Indian Express

This is probably a lesbian clich, but we played in the same soccer team, Rainer said. The two were teammates and friends for nearly three years before they began dating in the week leading up to Sinnenbergs graduation.

We found ourselves lingering, Sinnenberg said. When we would be hanging out with a group, we would stay and talk I remember standing in the Morgan staircase for an hour talking to Tyler.

Before their relationship with each other, neither Sinnenberg nor Rainer had ever dated another woman before. As they were navigating the formation of a new relationship, they were also navigating an unexplored facet of their identities.

Were obviously both gay, Sinnenberg laughed. So it was like, Oh, yeah, this is what its supposed to be like, you know what I mean?

Everything is more intense, Rainer agreed. Like more passion, more love, more fear, more all of this. All of the things are amplified.

At the same time, the fact that neither were public about their sexuality yet added a dimension of anxiety to their burgeoning relationship. Our Williams soccer community is some of the most loving, respectful, caring, open-minded humans that exist, Rainer said. But I think theres first-time fear and anxieties.

I think we had built it up, Sinnenberg agreed. It didnt end up being an issue. We used to go on dates to Northampton, so we could hold hands.

After Sinnenberg graduated, she moved to New York. While she originally planned to spend a year in South Africa, she ultimately decided to live and work closer to Rainer, who joined her the following year, after her own graduation. They separated for another year when Sinnenberg headed to Philadelphia, Pa. for medical school before Rainer joined her again.

Despite multiple periods of being long-distance, the two said they were simply happy to be together. We were basically not explicitly dating but in a romantic relationship over Skype, Sinnenberg said. It was definitely very emotional; it definitely felt like it was a relationship. So then, for it to go back to distance, I think probably felt kind of natural to us. It was sort of the way in which we had known each other.

When Sinnenberg proposed to Rainer, gay marriage had not yet been legalized nationwide. We kind of went into getting married thinking that we werent going to be able to make it legal on a federal level, Sinnenberg said.

But a month later, the Supreme Courts ruling in Obergefell v. Hodges legalized same-sex marriage across the country. We actually had friends who got married the weekend after it was legalized, Sinnenberg said. That was a pretty emotional time.

Rainer and Sinnenberg themselves were married in the Catskills, N.Y. Though they chose not to return to Williamstown for their wedding, as many other alums did, the College still has a strong presence in their lives. The home we live in currently is from Williams alums, Rainer said.

And our grill is from Williams alums, Sinnenberg added.

Read more:
The chemistry department: Alum couples reflect on College romance and beyond - The Williams record