Chemistry

Modular Blocks Help Fight Disease

May 18, 2018 by 3 Comments

When engineering a solution to a problem, an often-successful approach is to keep the design as simple as possible. Simple things are easier to produce, maintain, and use. Whether you’re building a robot, operating system, or automobile, this type of design can help in many different ways. Now, researchers at MIT’s Little Devices Lab have taken this philosophy to testing for various medical conditions, using a set of modular blocks.

Each block is designed for a specific purpose, and can be linked together with other blocks. For example, one block may be able to identify Zika virus, and another block could help determine blood sugar levels. By linking the blocks together, a healthcare worker can build a diagnosis system catered specifically for their needs. The price tag for these small, simple blocks is modest as well: about $0.015, or one and a half cents per block. They also don’t need to be refrigerated or handled specially, and some can be reused.

This is an impressive breakthrough that is poised to help not only low-income people around the world, but anyone with a need for quick, accurate medical diagnoses at a marginal cost. Keeping things simple and modular allows for all kinds of possibilities, as we recently covered in the world of robotics.

Continue reading “Modular Blocks Help Fight Disease” →

Computers May Someday Need A Drink

April 21, 2018 by 16 Comments

“We want to put water right into your processor.” If that statement makes you sweat, that is good. Sweating is what we’re talking about, but it’s more involved than adding some water like a potted plant. Sweating works naturally by allowing liquid to evaporate, and that phase change is endothermic which is why it feels cool. Evaporative coolers that work in this way, also known as swamp coolers, haven’t been put into computers before because they are full of sloshy water. Researchers in South Korea and the United States of America have been working on an evaporative cooling system mimicking the way some insects keep themselves cool by breathing through their exoskeletons while living in damp soil.

Springtails are little bugs that have to keep the water and air separate, so they don’t drown in the wet dirt where they live. Mother Nature’s solution was for them to evolve to do this with columns that have sharp edges at the exit. Imagine you slowly add water to a test tube, it won’t spill as soon as you reach the top, it will form a dome. This is the meniscus. At a large scale, say a river dam, as soon as you get over the dam you would expect spillage, but at the test tube level you can see a curve. At the scale of the springtail, exuded water will form a globe and resist water pressure. That resistance to water pressure allows this type of water cooling to self-regulate. Those globes provide a lot of surface area, and as they evaporate, they allow more water to replenish the globe. Of course, excessive pressure will turn them into the smallest squirt guns.

We have invented a lot by copying Mother Nature. Velcro was inspired by burrs, and some of our most clever robots copy insects. We can also be jerks about it.

Carbon Augmented Spider Silk

March 15, 2018 by 22 Comments

Some of the creepy-crawlers under our feet, flitting through the air, and waiting on silk webs, incorporate metals into their rigid body parts and make themselves harder. Like Mega Man, they absorb the metals to improve themselves. In addition to making their bodies harder, silk-producing creatures like worms and spiders can spin webs with augmented properties. These silks can be conductive, insulating, or stronger depending on the doping elements.

At Italy’s University of Trento, they are pushing the limits and dosing spiders with single-wall carbon nanotubes and graphene. The carbon is suspended in water and sprayed into the spider’s habitat. After the treatment, the silk is measured, and in some cases, the silk is significantly tougher and surpasses all the naturally occurring fibers.

Commercial spider silk harvesting hasn’t been successful, so maybe the next billionaire is reading this right now. Let’s not make aircraft-grade aluminum mosquitoes though. In fact, here’s a simple hack to ground mosquitoes permanently. If you prefer your insects alive, maybe you also like their sound.

Thank you for the tip, [gippgig].

A Salty Solution for a Dead Nexus 5X

January 16, 2018 by 98 Comments

If you’re an Android fan, there’s a good chance you’ve heard of the Nexus 5X. The last entry in Google’s line of low-cost Nexus development phones should have closed the program on a high note, or at the very least maintained the same standards of quality and reliability as its predecessor. But unfortunately, a well known design flaw in the Nexus 5X means that the hardware is essentially a time-bomb. There are far too many reports of these phones entering into an endless bootloop right around the one year mark to say it’s just a coincidence.

The general consensus seems to be that faulty BGA chip soldering on the CPU works lose after about a year or so of thermal stress. Whatever the reason, [hillbillysam] recently found himself the proud owner of a dead Nexus 5X. Resigned to the fact that he would need to get a new phone, he at least wanted to get some of his data off the device before it went to that big landfill in the sky.

As it turns out these bootlooped phones can temporarily be revived by cooling them down, say by putting them in the freezer for a few hours. There’s plenty of debate as to why this works, but even our own [Lewin Day] can testify that it does seem to get the phone booting again; though only until it comes back up to operating temperature. With this in mind, [hillbillysam] reasoned that if he kept the phone as cold as possible while it was running, it may stay operational long enough for him to pull his files off of it over USB.

He couldn’t exactly freeze the phone in a block of ice, but remembering his high school chemistry, he came up with something pretty close. By adding salt to water, you can significantly lower temperature at which it freezes. Putting the phone into a watertight bag and submerging it in this supercooled solution is an easy and non-destructive way of keeping it very cold while still being accessible over USB.

His Nexus 5X was able to keep kicking the whole time it was luxuriating in its below-freezing saltwater bath, giving him plenty of time to copy everything he needed. It doesn’t sound like the kind of spa day we’d like to have personally, but to each their own.

If your Nexus 5X has met a similar fate, you may want to take a look at our previous coverage about the issue. While your mileage may vary, we’ve reported on a couple of success stories so it’s worth a shot.

[via /r/nexus5x]

Marguerite Perey: When The Lab Assistant Gets The Credit

November 28, 2017 by 13 Comments

Most people obtain a bachelor’s degree before getting their masters, and even that is a prerequisite for a doctorate. Most people, however, don’t discover a new chemical element.

Marguerite Perey graduated with a chemistry diploma from Paris’ Technical School of Women’s Education in 1929, and applied for work at the Curie Institute, at the time one of the leading chemistry and physics labs in the world. She was hired, and put to work cataloging and preparing samples of the element actinium. This element had been discovered thirty years before by a chemist who had also been working in the Curie laboratory, but this was the height of the chemical revolution and the studies and research must continue.

When Marie Curie died in 1934, the discoverer of actinium, André-Louis Debierne, continued his research and Perey kept providing samples. Marguerite’s work was recognized, and in time she was promoted from a simple lab assistant to a  radiochemist. It would not be an exaggeration to say that Marguerite was, at the time, the world’s leading expert in the preparation of actinium. This expertise would lead her to the discovery of the bottom left corner of the periodic table: francium, element 87, the least electronegative element, and arguably the most difficult naturally occurring element to isolate.

Continue reading “Marguerite Perey: When The Lab Assistant Gets The Credit” →

How Pure is this Cup of Joe? Coffee, Conspiracy, and Citizen Science

November 6, 2017 by 37 Comments

Have you ever thought about coffee purity? It’s more something you’d encounter with prescription or elicit drugs, but coffee is actually a rather valuable commodity. If a seller can make the actual grounds go a bit further by stretching the brew with alternative ingredients there becomes an incentive to cheat.

If this sounds like the stuff rumors are made of, that’s because it is! Here in Ho Chi Minh City there are age-old rumors a coffee syndicate that masterfully passes off adulterated product as pure, high-grade coffee. Rumors are one thing, but the local media started picking up on these suspicions and that caught my attention. I decided to look to simple chemistry to see if I could prove or disprove the story.

What we want to investigate is whether price and coffee purity are related. If they are, then after accounting for the effect of price, we will want to know whether proximity to the market where artificial coffee flavoring is sold has an effect on coffee purity.

Continue reading “How Pure is this Cup of Joe? Coffee, Conspiracy, and Citizen Science” →

Yellowing: the Plastic Equivalent of a Sunburn

November 3, 2017 by 58 Comments

Your fancy white electronic brick of consumer electronics started off white, but after some time it yellowed and became brittle. This shouldn’t have happened; plastic is supposed to last forever. It turns out that plastic enclosures are vulnerable to the same things as skin, and the effects are similar. When they are stared at by the sun, the damage is done even though it might not be visible to you for quite some time.

Continue reading “Yellowing: the Plastic Equivalent of a Sunburn” →