National Institute of Standards and Technology (NIST)

Some people like plastic Christmas trees; others prefer real wood and needles. This year, NIST is printing a tree out of concrete.    The tree is not only festive; it’s also a test of the printing process and the skill of NIST researchers. 3D-printed concrete is a new construction technique that could be used to make everything from park benches to entire houses. But there are no building codes or standards yet for 3D-printed concrete. NIST is doing the basic research to understand the strength of these materials.    As a part of the research team’s training, they occasionally print particularly challenging objects such as this Christmas tree.    At 1.3 meters (4.5 feet), this is the tallest overhanging object ever printed at the lab. The scientists need to constantly tweak the concrete recipe to ensure it hardens fast enough to stay upright, yet slow enough to flow through the pumps and hoses of the printer.     The conical shape is particularly challenging because each layer is smaller than the last. This means it has less time to rest before the next layer is pressed on top of it and so it needs to harden slightly faster. The layers also hang a little over the inside edge of the layer below, so it’s possible for the walls to collapse inward if they aren’t careful.    Now that the experiment is done, do you have any ideas on how we should decorate it?    Happy Holidays!    #3Dprinting #AdditiveManufacturing #Concrete 

Chemistry, forensics, materials, IT – we have the data that you need. Enter the NIST Data Repository: https://lnkd.in/gF25cbfY   #Data #Chemistry #Forensics #MaterialsScience #InformationTechnology 

NIST researchers have been working to improve measurements of the long-lasting “forever chemicals” known as PFAS which have useful properties such as being heat-resistant but have also been found to pose risks to human health. NIST’s PFAS program has, among many other things, studied the amounts of these chemicals in firefighting gear. The latest study, featured in this issue, explores PFAS levels in the gloves and hoods of structural firefighters and the lightweight gear worn by wildland firefighters.

Clinical measurements are data your health care provider uses to make decisions about your care, such as cholesterol or testosterone levels. More than 500 million clinical measurements are taken each year in the U.S.     Providers can trust these measurements, in part, because of NIST.      We make standard reference materials, or SRMs, that labs and manufacturers use to ensure their equipment is making accurate measurements or to perform other quality control tests. SRMs are sometimes called “truth in a bottle.”     Making sure providers have reliable information to treat their patients is one of many ways our work impacts your daily life. Learn more in our latest Taking Measure blog post: https://lnkd.in/dh8Y7J4E   #ScienceAndTechnology #Standards 

Walk through the journey that time takes to get from our ensemble of atomic clocks in Boulder, Colorado, to your computer: https://lnkd.in/gNwjGYba   #Physics #Technology 

The “forever chemicals” known as PFAS are commonly used in firefighters’ protective gear to repel moisture. But these long-lived compounds have also been linked to an increased risk of cancer. Measuring the presence of these chemicals is the first step in reducing any potential impacts.    NIST researchers have been conducting a series of studies to understand how much PFAS is present in firefighter gear. Their latest study looks at the hoods and gloves worn by structural firefighters (firefighters who work in buildings) as well as the lightweight clothes worn by wildland firefighters.     Overall, they found measurable amounts of PFAS in 25 of the 32 textile samples they examined. Some textile layers didn’t contain much PFAS at all while others contained a relatively large amount.  Learn more about the new study: https://lnkd.in/eKJVR8nm   #Firefighters #PFAS #HealthAndSafety

Plug it in: Meet the first commercially built broadcast radio receiver that operated with alternating current (AC) delivered by the power grid (at 60 hertz).    In the early years of radio broadcasting, radio receivers were powered exclusively by batteries. The periodic need to change the batteries was inconvenient, to say the least. Batteries at that time were bulky, heavy, cumbersome and an acid-filled source of danger and damage in a household.    In the 1920s, NIST researchers showed that receivers could use household 110-volt AC without sacrificing performance quality. Using AC household current to power radio sets was much safer and more convenient for the consumer, which helped to expand radio ownership and propel the growth of the radio and broadcasting industries.    #History #Radio #Invention 

Freeze! Check out our latest roundup of position openings at NIST:    Electronics Engineer: https://lnkd.in/eF5eeffc    Maintenance Worker: https://lnkd.in/e-cwW2fr    Firefighter: https://lnkd.in/ev8DFFQ7    Mechanical Engineer: https://lnkd.in/g85Aii7q    Air Conditioning Engineer: https://lnkd.in/gbFDziCT    Browse our full listing of current openings at NIST: https://lnkd.in/d6KBevq    #NISTjob #JobOpening #JobOpportunities   

Looking for your next career move? How about NIST?     From physicists and engineers to IT specialists, electricians, and administrative staff, every role is vital to our success.     See what opportunities with NIST Careers could be in your future: https://lnkd.in/dFvqX6y   #NISTjob #NISTCareers #Careers 

This is not the festive feel you want in your home during the holiday season. If you have a Christmas tree, keep it well watered.    #Fire #FireSafety #Holidays #Christmas