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The Story Of The Quickening: Mercurial Metal

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Of all known metals, mercury is probably one of the most famous, if only for its lustrous, liquid form at room temperature. Over the centuries, it has been commonly used in a wide variety of applications, including industrial chemical processes, in cosmetics, for telescope mirrors, thermometers, fluorescent lamps, dental fillings, bearings, batteries, switches and most recently in atomic clocks.

Though hardly free from the controversy often surrounding a toxic heavy metal, it’s hard to argue the myriad ways in which mercury has played a positive role in humanity’s technological progress and scientific discoveries. This article will focus both on its historical, current, and possible future uses, as well as the darker side of this fascinating metal.

Shiny and Useful

Mercury has been highly prized for its use in art and decorations. It’s historically known to have been used in mercury fountains — exactly as it sounds, these were artistic fountains using mercury rather than water — with the most recent example being Alexander Calder’s 1937 Mercury Fountain. Yet for thousands of years, from the Mayans (Temple of the Feathered Serpent in Teotihuacan) to the Egyptians and the Chinese (Emperor’s Qin tomb), mercury was held in high esteem, with many considering it to hold special properties in addition to its remarkable physical properties.

Unfortunately, this led to it being used in medicine, especially in China and Tibet, where it was thought to prolong life, heal injuries and generally improve one’s health. It is rumored that a mixture of mercury and crushed jade given as an immortality mixture was what killed Emperor Qin. Alchemists considered mercury to be a Prima Materia (First Matter) from which other metals are derived.

A basic mercury-based switch.

Clearly more practical was the discovery around 500 BC of amalgams (from medieval Latin amalgama, “alloy of mercury”), the mixing of mercury with other metals which led to its use for dental fillings in China before 1000 AD and in Europe around 1528 AD. Much like the Chinese amalgams back then, dental amalgams today consist of mercury and a metal alloy of silver, tin, and copper.

While polymer resins are being used more commonly instead of amalgam in dentistry, amalgam remains superior in terms of longevity and durability, except for situations where the restored area would be directly visible (polymer resins being white), or the hole in the tooth is fairly small. Here polymer resins are the preferred material.

Despite the scares about mercury poisoning from the elemental mercury in amalgam dental fillings, studies have shown that the amounts of mercury released is low enough that it should pose no health risks. Regardless, dental offices in the EU are required to treat amalgam waste as hazardous waste. US dental offices are facing similar measures, but flushing the amalgam waste down the drain is still common practice.

The Distinction Between Useful and Hazardous

Even outside of dental amalgam, mercury manages to provoke fierce debates about its uses and perceived dangers. One of these involves the many organic compounds that contain mercury, the so-called organomercury compounds. This group includes methylmercury (commonly found in fish like tuna and salmon), ethylmercury , dimethylmercury, diethylmercury, and merbromin.

Commonly used as a preservative agent due to its antiseptic and antifungal properties, thiomersal is regularly used in everything from vaccines to ophthalmic (e.g. eyedrops) and nasal products as well as things like tattoo inks and mascara, where long-time sterility is essential. In the body, thiomersal is broken down into ethylmercury, which is significantly less dangerous to the body than methylmercury. While refrigeration is an alternative to thiomersal, it requires an uninterrupted cooling chain, which can be problematic in some areas, leading to the use of contaminated vaccines.

In the US, fears about the ‘mercury’ in vaccines (related to conspiracy theories involving autism caused by vaccines) led to thiomersal being removed from most vaccines despite a lack of scientific evidence for doing so. Due to a lack of data on ethylmercury’s effect on the body in the 1990s, the data for methylmercury was used instead. Later research showed this to be a wrong equivalence, instead showing just how much more harmful methylmercury is.

Incidentally, the same conspiracy theories that led to the removal of thiomersal from most vaccines is linked into a more grand conspiracy theory about autism being caused by environmental toxins, including lead, mercury and other heavy metals. Chelation therapy is supposed to remove these toxins. This is however strongly recommended against as it is not an effective treatment and can lead to kidney and other potentially fatal damage.

Don’t Eat That Fish

Methylmercury is the most common form of organomercury, as it’s formed from inorganic mercury by microbes that live in aquatic systems. The resulting methylmercury is readily consumed by algae, which in turn are consumed by ever larger fish and other aquatic organisms in a process called biomagnification. As a result, the consumption of fish is the largest source of methylmercury and mercury in general for the population.

Part of the aftermath of the TVA Kingston coal-fired plant fly ash spill, which released heavy metals into the environment.

Mercury poisoning became well known due to the sudden outbreak of the then new Minamata disease in Japan, which turned out to be caused by the release of methylmercury into the environment from chemical factories, ending up in aquatic organisms that the local population would then catch and consume. In Japan this disease would cost 1,784 lives of 2,265 officially identified victims. Other nations experienced their own outbreaks of this disease.

Even without deliberate spills of methylmercury or its precursors, the amount of mercury in the environment is such that for fish species like swordfish, tuna, cod and pike one should not eat more than 170 grams of it per week, to avoid an unhealthy bioaccumulation of mercury in one’s body. Some places like Florida’s Everglades end up acting like scrubbers for mercury that is released in the air, severely raising local mercury levels there, with the advice being to never eat fish caught in those areas.

Mercury Today and Tomorrow

It is hard to think of a world without mercury. Whether it’s in dentistry, industry, laboratories or in astronomy, an essential role is played by mercury in some fashion. In astronomy especially, mercury essentially enables liquid mirror telescopes, which provide a highly effective and low-cost alternative to expensive and fragile glass mirrors. Mercury sees common use as an electrode in chemistry and in X-ray crystallography studies of proteins in structural biology with the multiple isomorphous replacement (MIR) approach, even as its use in more mundane tasks such as diffusion vacuum pumps has diminished over time, it still remains relevant there, as recently covered on Hackaday.

Cody’s DIY Sprengel vacuum pump.

One of the most exciting new applications for mercury in the near future is that Jet Propulsion Lab’s Deep Space Atomic Clock (DSAC). The exciting thing about the DSAC is that it essentially takes the accuracy of a rubidium-based atomic clock (AC) and stuffs it into a package many times smaller. This is all courtesy of the properties of mercury ions which allowed for such a level of miniaturization, allowing it to be used in weight-sensitive applications, such as space probes and satellites.

Mercury in Space

The obvious advantage of the DSAC project is that the high clock stability improves the on-board time-tracking and thus navigation and communication abilities, which would be ideal for deep space missions. This is further detailed in a 2012 JPL paper on the project. It describes the crucial role the onboard timing source has on deep space navigation when it comes to forming multi-way coherent Doppler and range measurements. The essential benefit is that a spacecraft can do more by itself, with higher accuracy and higher useful data rates across the network.

Simplified diagram of the DSAC.

Mercury is similar to rubidium in that it has a hyperfine transition that emits a very precise electromagnetic signal. Much of the miniaturization is enabled by the fact that in a microwave-driven atomic clock (like in current rubidium ACs and the DSAC) the frequency that is required to drive the clock also determines the dimensions of the oscillator which drives the clock. Whereas a rubidium clock uses a paltry ~6.834 GHz, mercury-199 uses 40.5 GHz.

Render of the DSAC.

At those higher frequencies, the required circuitry and other components can be made much smaller, resulting in an atomic clock (current version) that’s a mere 29 by 26 by 23 cm at 17.5 kg, yet show no more drift than about 1 microsecond in 10 years of operation.

A DSAC prototype was launched on June 25th 2019 from Kennedy Space Center on a SpaceX Falcon Heavy rocket, as part of the Orbital Test Bed (OTB) satellite, which hosts four additional payloads in addition to the DSAC. NASA activated the DSAC prototype on August 23rd, with the entire mission expected to take about a year.

Being the Right Atom, in the Right Place

Throughout history, mercury has been a bit of a celebrity metal. In addition to its highly unusual liquid state at room temperature, it has enabled many areas of science to progress in ways that would have been difficult without mercury. Whether one looks at diffusion pumps and mercury thermometers, its myriad roles in chemistry and industry, the preservation of vaccines and similar substances, it’s hard to think of a material which has impacted human civilization more in ways that are subtle but ever-present.

Now it appears that mercury will be with us on our journey to the final frontier as well, keeping our space probes and possibly crewed space ships safe as they travel to Mars, Venus, and beyond. Here’s to a long, healthy relationship with a really special metal.



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Why You Should Remove Xiaomi’s Default MIUI Cleaner App?

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Two weeks ago, India banned 59 Chinese apps, citing that they “pose a threat to sovereignty and security of our country.” The list includes some of the most downloaded Android and iOS apps such as TikTok, UC Browser, ShareIT, and the app that concerns Xiaomi users — Clean Master by Cheetah Mobile.

The Indian government said Clean Master and other Chinese apps have been “stealing and surreptitiously transmitting users’ data in an unauthorized manner to servers which have locations outside India.”

Clean Master, as the name suggests, is a cleaner app that promises to clear the junk files on the device and boost performance. Although Android cleaners ironically work against the device (more on this below), the bigger problem with Clean Master is that it is owned by Cheetah Mobile. Cheetah Mobile has been under the radar of privacy experts long before India noticed suspicious activity around its apps. The Chinese company has previously been caught in ad fraud and user data theft.

While CleanMaster has been removed from the Google Play Store and App Store in India, it is still being pushed as a default cleaner app in Xiaomi, one of the biggest smartphone manufacturers in India.

How to remove Xiaomi’s MIUI Cleaner app?

All Xiaomi and Redmi devices come with a cleaner app pre-installed known as MIUI Cleaner app. If you go into the app settings, you will notice that the app uses the Clean Master definition. Apart from that, the app brings up “Cheetah Mobile” a number of times in its privacy policy.

Unfortunately, Xiaomi doesn’t allow users to uninstall or even disable several default apps (also known as Bloatware), and one of them is MIUI Cleaner app. But here is a workaround to remove MIUI Cleaner app —

Prerequisite:
A Windows PC
USB cable to connect the device to the PC
USB debugging turned on the Xiaomi device

  • Connect your Xiaomi device to PC using the USB cable
  • Allow the USB debugging prompt on your device
    USB debugging Android Prompt
  • Download and extract ADB tools
  • Go to the extracted folder. Right-Click and choose “Open PowerShell Window here”
    How to use ADB tools
  • Type in the command “adb devices” and hit Enter
    ADB tools for deleting android apps
  • You will now see a number and “device” under the list of devices attached
  • Type in the command “adb shell,” press enter, then type, “pm uninstall –k —user 0 com.miui.cleanmaster” and hit Enter.
  • Remove the USB cable and restart your Xiaomi device

And that’s it, this process will remove MIUI Cleaner app. It is a universal process to remove pre-installed apps on any Android device. In other words, you can follow the same method if you have a Realme, Oppo, or any other Chinese smartphone.

Previously, Mi browser was accused of collecting data from users. You can use this method to remove the Mi browser or any default apps. What you need is the app’s package name and insert it in the “pm uninstall –k —user 0 <app package>” command. Use App Inspector to find out the exact name of the app.

Alternatives to Xiaomi MIUI Clearer

Over the years, Android has become extremely efficient in handling apps and background services. It intelligently allocates resources to apps and pauses apps that are not being used frequently. Most cleaner apps offer a performance boost which is simply force-quitting all background apps. While it may give a performance jump, it can create problems with Android’s way of doing things.

The only useful feature of a cleaner app is allowing users to delete unwanted apps and data under one roof. However, in return, it may collect user data. That being said, if you still want a cleaner app, you can start with SDMaid which does a pretty good job and keeps your data secure. Alternatively, you can also choose from our best cleaner apps list.

The post Why You Should Remove Xiaomi’s Default MIUI Cleaner App? appeared first on Fossbytes.



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Another big Galaxy Z Fold 2 leak spoils the phone’s specs

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  • Samsung’s Galaxy Z Fold 2 specifications and features have leaked once again in a comprehensive report from Korean tech news site ETNews.
  • According to the report, the Galaxy Z Fold 2 will feature a 7.7-inch AMOLED display inside the fold and a 6.23-inch AMOLED Cover Display on the outside.
  • Samsung will hold its next Galaxy Unpacked event on August 5th.

On July 7th, Samsung sent out invitations to its virtual Galaxy Unpacked event, which take place on August 5th and feature their “latest ecosystem of Galaxy devices.” Rumors and reports that have popped up over the last few months led us to believe that the “ecosystem” would include a Galaxy Note 20, Galaxy Z Flip 5G, and Galaxy Z Fold 2, but it’s now being reported that the sequel to the Galaxy Fold could be delayed. Regardless, that hasn’t stopped the internet from attempting to spoil every last feature and specification of the foldable phone.

A recent report from South Korea’s ETNews claims the Galaxy Z Fold 2 (which is rumored to be the rebranded name of the phone that will follow the Galaxy Fold) will feature a 7.7-inch Youm On-Cell Touch AMOLED (Y-OCTA) display with a refresh rate of 120Hz and the same Ultra-Thin Glass found on the Galaxy Z Flip.

This isn’t the first time that we’ve heard about an even larger display for the Fold 2, but the leak doesn’t end there.

According to ETNews, the Galaxy Z Fold 2 will also feature a 6.23-inch Cover Display (a significant upgrade from the 4.6-inch outer screen of the original) and a biometric fingerprint scanner mounted on the side. As for the cameras, the Z Fold 2 is said to have two 10-megapixel selfie cameras — one on the inside and one on the outside — as well as a rear-facing triple-lens camera array. The primary array features a 12-megapixel camera with a wide-angle lens, a 12-megapixel camera with an ultra wide-angle lens, and a 64-megapixel telephoto camera.

As SamMobile notes, if this report is accurate, the Galaxy Z Fold 2 will have the same setup as the Galaxy S20.

As for battery power, ETNews says that the Z Fold 2 will support 15W fast wireless charging as well as 15W reverse wireless charging (which is when you charge another device with your phone). Previous reports have suggested that Samsung will put both a 2,090 mAh battery and a 2,275 mAh battery inside the Galaxy Z Fold 2, giving the phone a total battery capacity of 4,365 mAh. We also expect the phone to feature a Snapdragon 865+ processor, 12GB of RAM, support for 5G networks, and up to 256GB of storage. At this point, there’s very little we don’t know.

We still do not know when an official announcement from Samsung will arrive, but August 5th is still weeks away, so perhaps the company will sort out any issues and reveal the Galaxy Z Fold 2 at the Unpacked event.



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Government dumps Huawei from UK’s 5G network in massive U-turn

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The logo of Chinese company Huawei is on view at their main UK offices in Reading, west of London (Daniel Leal-Olivas/AFP via Getty Images)

Huawei has been denied access to the UK’s 5G telecoms network just six months after it was given the all-clear by the government.

The dramatic u-turn was announced today following mounting pressure on Boris Johnson’s cabinet not to include the Chinese tech giant in Britain’s infrastructure.

In January the government said that Huawei could supply up to 35% of the equipment for the UK’s 5G plans but would be kept out of the core network.

But now it has been made clear the company will not be allowed to install any equipment at all from next year.

Oliver Dowden, the culture secretary, told MPs that the government will now no longer allow Huawei to supply kit for use in 5G networks operated by the likes of BT, O2 and Three.

Speaking in the House of Commons, Mr. Dowden said that telecoms operators will not be allowed to buy equipment from Huawei from the end of the year and that a complete removal of all Huawei kit will take place by 2027.

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‘5G will be transformative for our country, but only if we have confidence in the security and resilience of the infrastructure it is built upon,’ he said.

‘Following US sanctions against Huawei and updated technical advice from our cyber experts, the government has decided it is necessary to ban Huawei from our 5G networks. 

‘No new kit is to be added from January 2021, and UK 5G networks will be Huawei free by the end of 2027. This decisive move provides the industry with the clarity and certainty it needs to get on with delivering 5G across the UK.

‘By the time of the next election we will have implemented in law an irreversible path for the complete removal of Huawei equipment from our 5G networks.’

‘This has not been an easy decision, but it is the right one for the UK telecoms networks, for our national security and our economy, both now and indeed in the long run,’ he told MPs.

The decision comes after the United States moved to impose further sanctions on Huawei, which it believes is a tool for espionage used by the Chinese government. Last month the US Federal Communications Commission branded Huawei a threat to ‘national security.’

Huawei has long denied the accusations from the Trump administration but the latest round of US sanctions have had consequences. Huawei is no longer allowed to use American-made processor chips, forcing it to look elsewhere.

This, in turn, led the UK’s National Cyber Security Centre (NCSC) to launch a review of the company’s involvement in national networks.

Technical experts at the NCSC reviewed the consequences of the sanctions and concluded Huawei will need to do a major reconfiguration of its supply chain as it will no longer have access to the technology on which it currently relies and there are no alternatives which it has ‘sufficient confidence’ in.

They found the new restrictions make it impossible to continue to guarantee the security of Huawei equipment in the future. 

Ed Brewster, a spokesperson for Huawei UK, said: ‘This disappointing decision is bad news for anyone in the UK with a mobile phone. It threatens to move Britain into the digital slow lane, push up bills and deepen the digital divide. Instead of ‘levelling up’ the government is levelling down and we urge them to reconsider. We remain confident that the new US restrictions would not have affected the resilience or security of the products we supply to the UK.

‘Regrettably our future in the UK has become politicized, this is about US trade policy and not security. Over the past 20 years, Huawei has focused on building a better connected UK. As a responsible business, we will continue to support our customers as we have always done.

‘We will conduct a detailed review of what today’s announcement means for our business here and will work with the UK government to explain how we can continue to contribute to a better connected Britain.’



The debate around Huawei

A woman walks by a Huawei retail store in Beijing. (AP Photo/Andy Wong, File)

A woman walks by a Huawei retail store in Beijing (AP Photo/Andy Wong, File)

Here is a look at the key issues in the debate around Huawei.

What is Huawei?

Huawei is the Chinese telecoms giant which describes itself as a private company ‘fully owned by its employees’.

In recent years, its range of smartphones have become commonplace across the UK, and it is now established as one of the biggest smartphone manufacturers in the world, alongside Apple and Samsung.

In addition to making mobile devices, the firm also makes telecommunications networks.

Why is the company controversial?

Huawei has come under criticism over its alleged close ties to the Chinese state.

The country has a history of state censorship and surveillance, such as the ‘Great Firewall of China’ which blocks multiple internet services in the country and, under Chinese law, firms can be compelled to ‘support, co-operate with and collaborate in national intelligence work’.

As a result, critics of Huawei have expressed concerns that Beijing could require the firm to install technological ‘back doors’ to enable it to spy on or disrupt Britain’s communications network.

The US is a strong critic of the firm and last year President Donald Trump added Huawei to the Entity List, effectively blacklisting the firm and preventing it from trading with US companies.

Consequently, Huawei has not been able to use core Google apps on its newest smartphones as part of the Android operating system it uses to power the devices.

However the firm has always denied any suggestions of close links with the Chinese state or that it has ever been asked by Chinese authorities to help spy on others, insisting it fully abides by the laws of each country in which it operates.

How is it linked to 5G?

As well as its smartphone business, Huawei is one of the market leaders in telecoms infrastructure equipment, including that for 5G.

The next generation of mobile data communications, 5G has been rolling out to areas of the UK for the last year.

The new networks allow for larger amounts of data to be transferred at once, which could one day power new technologies such as autonomous car networks and remote surgery where specialist surgeons cannot reach a hospital physically.

As a result, a great deal of debate among telecoms firms and governments is ongoing over how to secure such a data-sensitive network, which has led to the scrutiny of Huawei.

Earlier today, former BP chief Lord Browne stepped down as the chairman of Huawei UK six months before his tenure was due to end.

‘The UK has had a very long relationship with China and I hope it’s not one that they simply throw away,’ he told Reuters last week.

A Huawei spokesperson said: ‘When Lord Browne became Chairman of Huawei UK’s board of directors in 2015, he brought with him a wealth of experience which has proved vital in ensuring Huawei’s commitment to corporate governance in the UK. He has been central to our commitment here dating back 20 years, and we thank him for his valuable contribution.’

Engineers from EE the wireless network provider, owned by BT Group Plc, check on 5G masts and Huawei Technologies Co. 5G equipment undergoing trials in the City of London, U.K., on Friday, March 15, 2019. Europe would fall behind the U.S. and China in the race to install the next generation of wireless networks if governments ban Chinese equipment supplier Huawei Technologies Co. over security fears, according to an internal assessment by Deutsche Telekom AG. Photographer: Simon Dawson/Bloomberg via Getty Images

Engineers from EE the wireless network provider, owned by BT Group Plc, check on 5G masts and Huawei Technologies Co. 5G equipment undergoing trials in the City of London, U.K., on Friday, March 15, 2019 (Bloomberg via Getty Images)

Earlier this month, executives from Vodafone and BT told the Science and Technology Select Committee they would need at least five years to completely remove the Chinese firm’s equipment without causing disruption which could cause signal blackouts for several days.

‘Should the guidance become stricter it will have an effect, it will delay the rollout of our 5G, it will have cost implications and focus our investment in the removal of the existing equipment,’ Andrea Dona, Vodafone UK’s head of networks said.

According to Huawei, it employs about 1,600 people in the UK says it is one of the largest investments in Britain from China.

It doesn’t have publicly traded shares and it doesn’t provide any kind of regional breakdown of its revenue. However, it said that despite the US sanctions and the coronavirus pandemic it achieved a 13% rise in sales for the first half of 2020 compared to the same period in 2019, totalling 454 billion yuan or £51.3 billion.

Huawei is also expecting similar decisions to be made by Germany later this year.

Meng Wanzhou, the company’s chief financial officer and daughter of Huawei founder Ren Zhengfei, is currently under house arrest in Canada, in an extradition trial that could result in her being sent to the US to face charges that include bank fraud and a violation of trade sanctions.



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