World's most heat resistant material found

December 25, 2016

London, Dec 25: Scientists have identified materials that can withstand temperatures of nearly 4,000 degrees Celsius, an advance that may pave the way for improved heat resistant shielding for the faster-than-ever hypersonic space vehicles.heat

Researchers from Imperial College London in the UK discovered that the melting point of hafnium carbide is the highest ever recorded for a material.

Tantalum carbide (TaC) and hafnium carbide (HfC) are refractory ceramics, meaning they are extraordinarily resistant to heat. Their ability to withstand extremely harsh environments means that refractory ceramics could be used in thermal protection systems on high-speed vehicles and as fuel cladding in the super-heated environments of nuclear reactors.

However, there has not been the technology available to test the melting point of TaC and HfC in the lab to determine how truly extreme an environment they could function in. The researchers developed a new extreme heating technique using lasers to test the heat tolerance of TaC and HfC.

They used the laser-heating techniques to find the point at which TaC and HfC melted, both separately and as mixed compositions of both.

They found that the mixed compound (Ta0.8Hf0.20C) was consistent with previous research, melting at 3,905 degrees Celsius, but the two compounds on their own exceeded previous recorded melting points. The compound TaC melted at 3,768 degrees Celsius, and HfC melted at 3,958 degrees Celsius.

The findings may pave the way for the next generation of hypersonic vehicles, meaning spacecraft could become faster than ever.

"The friction involved when travelling above Mach 5 -hypersonic speeds - creates very high temperatures," said Omar Cedillos-Barraza, currently an Associate Professor at the University of Texas.

"So far, TaC and HfC have not been potential candidates for hypersonic aircraft, but our new findings show that they can withstand even more heat than we previously thought - more than any other compound known to man," said Cedillos-Barraza, who carried out the research as a PhD student at Imperial College London

"This means that they could be useful materials for new types of spacecraft that can fly through the atmosphere like a plane, before reaching hypersonic speeds to shoot out into space," he said.

"These materials may enable spacecraft to withstand the extreme heat generated from leaving and re-entering the atmosphere," he added.

Examples of potential uses for TaC and HfC could be in nose caps for spacecraft, and as the edges of external instruments that have to withstand the most friction during flight.

Currently, vehicles going over Mach 5 speeds do not carry people, but Cedillos-Barraza suggests it may be possible in
the future.

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News Network
February 5,2020

Feb 5: Tesla is making Elon Musk a lot richer without paying him a dime.

A blistering stock rally has bolstered the value of CEO Musk's 19% stake in the electric car maker by $16 billion since the start of 2020, to $30 billion.

Tuesday's steep climb in the share price could sweeten Musk's payday under his record-breaking compensation package, which is built on stock options that rely on market value targets. Two milestones have now been achieved that could see Musk unlock options worth $1.8 billion.

The controversial chief executive, who is also the majority owner and CEO of rocket maker SpaceX, recently testified that he did not have a lot of cash as he successfully defended himself in a defamation lawsuit. He previously has taken loans using his Tesla shares as collateral.

Musk does not take a salary, choosing instead a risky options package that envisions the stock market value of Tesla rising to $650 billion over 10 years, a prospect that was derided by some investors when the deal was announced in 2018.

That target now looks less crazy. Shares of Tesla have rallied over 50% since the company posted its second consecutive quarterly profit last Wednesday, which was viewed as a major accomplishment for a company competing against established automotive heavyweights including General Motors Co  and BMW.

Tesla shares have climbed about 400% since early June, helped by the company's better-than-expected financial results and ramped-up production at its new car factory in Shanghai.

On Tuesday, Tesla surged as much as 24% before falling back in the final minutes of the trading session to end the day up 13.7%. That put its market capitalization at $160 billion, almost twice the combined value of Ford Motor and General Motors.

The shares had also rallied on Monday, partly fueled by Panasonic Corp's 6752.T saying its automotive battery venture with Tesla was profitable for the first time.

The options Musk was awarded in 2018 vest incrementally based on targets for Tesla's stock market value and its financial performance. The market capitalization would have to sustainably rise by $50 billion increments over the agreement's 10-year period, with the full package payout reached if the market cap reaches $650 billion, as well as the company's meeting revenue and profit targets.

Musk is on his way to seeing his first two tranches of options vest. He achieved operational targets on revenue and adjusted earnings last year.

The rise in Tesla's market capitalization last month to a target of $100 billion opened the way for Musk's first tranche of options to vest. With Tuesday's surging share price, the market capitalization blew past the second target of $150 billion, opening the way for the second tranche to vest. Tesla's market capitalization must stay at or above each target level for one- and six-month averages for each set of options to vest.

Tesla was valued at about $52 billion when shareholders approved the pay package in March 2018, a time when the company faced a cash crunch, production delays and increasing competition from rivals.

A full payoff for Musk would surpass anything previously granted to U.S. executives, according to Institutional Shareholder Services, a proxy advisor that recommended investors reject the pay package deal at the time.

Musk currently owns about 34 million Tesla shares, and his compensation package would let him buy another 20.3 million shares if all his options tranches vest.

When Tesla unveiled Musk’s package, it said he could in theory reap as much as $55.8 billion if no new shares were issued. However, Tesla has since awarded stock to employees and last year sold $2.7 billion in shares and convertible bonds, diluting the value of the stock.

Musk has transformed Tesla from a niche car maker with production problems into the global leader in electric vehicles, with U.S. and Chinese factories. So far it has stayed ahead of more established rivals including BMW and Volkswagen.

Many investors remain skeptical that Tesla can consistently deliver profit, cash flow and growth. More Wall Street analysts rate Tesla "sell" than "buy," and the company's stock is the most shorted on Wall Street.

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News Network
May 7,2020

Toronto, May 7: Scientists have uncovered how bats can carry the MERS coronavirus without getting sick, shedding light on what triggers coronaviruses, including the one behind the COVID-19 pandemic, to jump to humans.

According to the study, published in the journal Scientific Reports, coronaviruses like the Middle East respiratory syndrome (MERS) virus, and the COVID19-causing SARS-CoV-2 virus, are thought to have originated in bats.

While these viruses can cause serious, and often fatal disease in people, bats seem unharmed, the researchers, including those from the University of Saskatchewan (USask) in Canada, said.

"The bats don't get rid of the virus and yet don't get sick. We wanted to understand why the MERS virus doesn't shut down the bat immune responses as it does in humans," said USask microbiologist Vikram Misra.

In the study, the scientists demonstrated that cells from an insect-eating brown bat can be persistently infected with MERS coronavirus for months, due to important adaptations from both the bat and the virus working together.

"Instead of killing bat cells as the virus does with human cells, the MERS coronavirus enters a long-term relationship with the host, maintained by the bat's unique 'super' immune system," said Misra, one of the study's co-authors.

"SARS-CoV-2 is thought to operate in the same way," he added.

Stresses on bats, such as wet markets, other diseases, and habitat loss, may have a role in coronavirus spilling over to other species, the study noted.

"When a bat experiences stress to their immune system, it disrupts this immune system-virus balance and allows the virus to multiply," Misra said.

The scientists, involved in the study, had earlier developed a potential treatment for MERS-CoV, and are currently working towards a vaccine against COVID-19.

While camels are the known intermediate hosts of MERS-CoV, they said bats are suspected to be the ancestral host.

There is no vaccine for either SARS-CoV-2 or MERS, the researchers noted.

Follow latest updates on the COVID-19 pandemic here

"We see that the MERS coronavirus can very quickly adapt itself to a particular niche, and although we do not completely understand what is going on, this demonstrates how coronaviruses are able to jump from species to species so effortlessly," said USask scientist Darryl Falzarano, who co-led the study.

According to Misra, coronaviruses rapidly adapt to the species they infect, but little is known on the molecular interactions of these viruses with their natural bat hosts.

An earlier study had shown that bat coronaviruses can persist in their natural bat host for at least four months of hibernation.

When exposed to the MERS virus, the researchers said, bat cells adapt, not by producing inflammation-causing proteins that are hallmarks of getting sick, but instead by maintaining a natural antiviral response.

On the contrary, they said this function shuts down in other species, including humans.

The MERS virus, the researchers said, also adapts to the bat host cells by very rapidly mutating one specific gene.

These adaptations, according to the study, result in the virus remaining long-term in the bat, but being rendered harmless until something like a disease, or other stressors, upsets this balance.

In future experiments, the scientists hope to understand how the bat-borne MERS virus adapts to infection and replication in human cells.

"This information may be critical for predicting the next bat virus that will cause a pandemic," Misra said.

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Agencies
June 12,2020

New Delhi, Jun 12: The Supreme Court on Friday asked Solicitor General Tushar Mehta to convene a meeting of the Finance Ministry and RBI officials over the weekend to decide whether interest incurred on EMIs during the moratorium period can be charged by banks.

A bench comprising Justices Ashok Bhushan, Sanjay Kishan Kaul and M.R. Shah queried Mehta as the court was concerned since the Centre has deferred loan for three months.

"Then how can interest of these 3 months be added?" the apex bench asked. Mehta replied: "I need to sit down with the RBI officials and have a meeting."

SBI's counsel, senior advocate Mukul Rohatgi, intervened during the proceedings and said "all banks are of the view that interest cannot be waived for a six month EMI moratorium period".

"We need to discuss it with the RBI," insisted Rohatgi.

Justice Bhushan then asked Mehta to convene a meeting of the RBI and Finance Ministry officials over the weekend, and listed the matter for further hearing on June 17.

The top court, during the hearing, indicated that it was not considering a complete waiver of interest but was only concerned that postponement of interest shouldn't accrue further interest on it.

After the RBI said the waiver of interest charges on EMIs during moratorium will lead to loss of 1 per cent of the nation's GDP, the top court had earlier asked the Finance Ministry to reply, whether the interest could be waived or it would continue during the moratorium period.

The top court said these are not normal times, and it is a serious issue, as on one hand moratorium is granted and then, the interest is charged on loans during this period.

"There are two issues in this (matter). No interest during the moratorium period and no interest on interest," said Justice Bhushan. The observation from the bench came on a petition by Gajendra Sharma, in which he sought a direction to declare portion of the RBI's March 27 notification as ultra vires to the extent it charged interest on the loan amount during the moratorium period.

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