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Eleven researchers publish sharp critique of EPA fuel economy logic

Ars - Sun, 2018-12-09 14:30

Enlarge / Cars zoom past during rush hour on Interstate 10 after sunset in El Paso, Texas, on November 27, 2018. (credit: PAUL RATJE/AFP/Getty Images)

In this week's edition of Science, eleven researchers from prominent universities around the US criticized the federal government's justification for rolling back vehicle fuel economy standards. They wrote that the economic assumptions made in the government's 2018 report resulted in a "flawed" analysis that will likely result in more traffic fatalities, more congestion, and more greenhouse gases emitted.

The Environmental Protection Agency (EPA) under Trump has moved to rescind a number of environmentally-minded regulations instituted under the Obama Administration. One of the first in its crosshairs was the EPA's Greenhouse Gas (GHG) standards for light trucks and passenger vehicles, which paralleled the Corporate Average Fuel Economy (CAFE) standards from the National Highway Traffic Safety Administration (NHTSA). These two regulations (the GHG and CAFE rules) both aimed to force automakers to adhere to gradually-tightening fuel efficiency standards, which were detailed out to 2025.

The EPA under Administrator Scott Pruitt spent most of 2017 laying the groundwork to rescind the GHG rules, saying the rules were onerous for automakers. But it's hard to rescind and replace existing law—agencies need to justify their decisions with robust studies showing that a rules change will improve the livelihood of Americans, whether in health or in jobs.

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Greenland’s melting snow makes new hockey stick (graph)

Ars - Sun, 2018-12-09 09:00

Enlarge / Staring down the barrel of an ice core drill. (credit: Sarah Das / WHOI)

The Greenland Ice Sheet’s unhealthy and rapid weight loss—and contribution to sea-level rise—occurs by a handful of mechanisms. In short, ice at the edge of the glacier can melt or break off into icebergs, and surface snow farther inland can melt. That snow melt is a bit like rainfall, in that it can either soak into the snow or runoff in streams.

Where it trickles down into the denser snow beneath, it refreezes and forms a stubborn layer that will continue to be visible when that snow is compressed into glacial ice. That means that drilling an ice core can give you a record of past surface melting events.

Greenland has experienced a remarkable amount of surface melting over the past couple decades, including the record-setting summer of 2012 that saw virtually the entire ice sheet melting at the surface. Because surface melting had historically been an unusual event akin to newsworthy heat waves, glaciologists wanted to put this into context. How much of Greenland’s recently accelerating ice loss was due to natural variability, and how much was due to human-caused trends?

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Tiny ceramic particles make this building material fire-safe

Futurity.org - Fri, 2018-12-07 15:40

Inspired by the insulation on a humble electrical cable, researchers have found that tiny ceramic particles can make plastic-backed cladding fire-safe.

How do you make a light-weight cladding material that doesn’t catch fire? It’s a question the building industry globally is wrestling with in the wake of the 2017 Grenfell Tower blaze in London that cost the lives of 72 people.

But according to new research, the answer is under your desk in the plastic insulation around the electrical cable powering your computer.

New codes require better cladding

The cladding on the Grenfell Tower was a widely-used, plastic-backed aluminum that is being blamed for how quickly the fire spread, as the polyethylene core melted and then combusted.

Various building codes have since tightened up on the use of combustible cladding, and two Australian states—New South Wales and Victoria—have recently introduced bans on cladding comprised of greater than 30 percent polyethylene.

The new codes make it virtually impossible for any plastic-backed cladding to pass combustion tests, leaving the industry facing much higher cladding costs. Cladding typically accounts for 10 to 30 percent of a high-rise building’s total costs.

Cladding is preferably lightweight; the secret is to use organic (carbon-based) composite materials like plastic, but organic materials by their nature are combustible. Non-combustible materials like steel, ceramic tiles, or concrete are much heavier and involve significantly higher material and installation costs.

So, when construction materials company Envirosip approached Kate Nguyen, research leader at the University of Melbourne’s Innovative Fire Engineering Group, to develop a cost-effective, non-combustible, light-weight cladding material, her first thought was that it was impossible.

Almost impossible.

Inspired by electrical cables

Nguyen had already done some research showing that when particles of clay and ceramic resin are incorporated inside a plastic composite they can effectively stop the material from combusting. But, she says, the high costs involved currently makes the technology impractical.

Instead, she went searching for ideas in the research literature and it was here she discovered that the answer might be in the way electrical cables are insulated.

“We believe we have developed something special that will be significant for the industry.”

“Instead of using the ceramic resin that I’d been looking at, the plastic insulation around electrical cables uses tiny ceramic particles that effectively do the same thing,” says Nguyen. “At high temperatures, the ceramic particles activate and chemically interact with each other, forming and spreading a heat-resistant network through the material.”

Of course, cladding needs to be able to withstand much higher temperatures than the insulation around electrical copper wires—750°C (1382°F) to be exact. But, in cooperation with Envirosip and a third-party chemical company, Nguyen began experimenting with different ceramic particles.

After several false starts, Nguyen and her partners came up with a formulated material that passed the test.

“When it passed I was excited, of course, but I immediately started panicking because I knew it might just be a mistake—independent testing sites are required to test materials at least five times before they can be approved.

“But even after it passed the fifth test I still couldn’t quite believe it, so I turned to my research assistant and said we’d better do a sixth one just to be sure,” Nguyen says.

She needn’t have bothered.

Next step: commercialization

An independent testing facility approved by the National Association of Testing Authorities later came up with exactly the same results. The product not only achieved the Australian combustibility standard AS1530.1:1994 (R2016), but also the more exacting ISO1182:2010 standard that is used internationally.

“I was really nervous because when I arrived they kept telling me about all the times they’d had samples fail. But when we passed the first test I knew we had something that would work—it was a great feeling,” Nguyen says.

The material itself is lightweight and feels like a compressed-powder. A pale grey color, the tiny ceramic particles appear as dark specks. At high temperatures these particles blend with the rest of the material, turning it a dark grey and rendering it non-combustible.

The research team is working further on a sprayable form of the material as a non-combustible membrane. Researchers at Melbourne and Envirosip will now try to commercialize the development work.

“When you are doing research, not all ideas will become successful. To go from success to commercialization is another big step as well, but we believe we have developed something special that will be significant for the industry.”

Nguyen presented the research at the 2018 Fire Safety and Cladding conference in Sydney, Australia.

Source: University of Melbourne

The post Tiny ceramic particles make this building material fire-safe appeared first on Futurity.

Install Nagios core 4.4.1 on Ubuntu 18.04 Server

Ubuntu Geek - Thu, 2018-08-16 18:25

Sponsored Link (adsbygoogle = window.adsbygoogle || []).push({}); Nagios® Core is an Open Source system and network monitoring application. It watches hosts and services that you specify, alerting you when things go bad and when they get better.Nagios Core was originally designed to run under Linux, although it should work under most other unices as well.
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Install Webmin on Ubuntu 18.04 (Bionic Beaver) Server

Ubuntu Geek - Wed, 2018-08-15 10:03

Webmin is a web-based interface for system administration for Unix. Using any modern web browser, you can setup user accounts, Apache, DNS, file sharing and much more. Webmin removes the need to manually edit Unix configuration files like /etc/passwd, and lets you manage a system from the console or remotely.
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