When a rainforest is clearcut for agricultural use, we only see the surface problems: fewer trees, destruction of plant and animal habitats, and countless other negative effects on the environment. A lurking problem, however, is that the soil is often non-ideal for farming. When the soil is exhausted, the farmers move further into the rainforest and repeat the process.
In the Amazon, however, there are pockets of man-made soil that are incredibly nutrient-dense. Figuring out how to make this soil, known as Terra Preta, on a massive scale would limit the amount of forest destruction by providing farmers a soil with more longevity which will, in turn, limit the encroachment on the rainforest. That’s the goal of this Hackaday Prize entry by [Leonardo Zuniga]: a pyrolysis chemical reactor that can make this soil by turning organic matter into a type of charcoal that can be incorporated into the soil to make Terra Preta.
As a bonus to making this nutrient-dense soil on a massive scale, this reactor also generates usable energy as a byproduct of processing organic waste, which goes several steps beyond simple soil enrichment. If successful and scalable, this project could result in more efficient farming techniques, greater yields, and, best of all, less damage to the environment and less impact on the rainforests.
There is one constant in the world of hardware hacker’s workshops, be they a private workshop in your garage or a public hackspace, and it goes something like this:
Everybody’s a safety expert in whatever it is they are working with, right up until the accident.
In other words, it is very tempting to harbour a cavalier attitude to something that either you are familiar with or the hazards of which you do not understand, and this breeds an environment in which mishaps become a distinct possibility.
As hardware people, we are familiar with basic tool safety or electrical safety. The chances are that we’ve had it drummed into us at some time in our growing up, by a lab supervisor, a workshop teacher, or a parent. That you as readers and I as writer have survived this long is testament enough to the success of that education. But what about those areas in which we may not have received such an education, those things which we either encounter rarely or seem harmless enough that their safety needn’t be our concern? Chemicals, for example: everything from glue through solvents and soldering consumables to PCB chemicals and even paint. It all seems safe enough, what could possibly go wrong? The answer to that question is probably something most of us would prefer never to find out, so it’s worth looking in to how a well-run workshop can manage its chemicals in as safe a manner as possible.
Continue reading “Sort Out Chemical Storage For Your Shop”
[The Plutonium Bunny] saw homegrown tin crystals on YouTube and reckoned he could do better—those crystals were flimsy and couldn’t stand up outside of the solution in which they were grown. Having previously tackled copper crystals, he applied the same procedure to tin.
Beginning with a 140 ml baby food jar filled with a solution of tin II chloride, 90 grams per liter, with a small amount of HCl as the electrolyte. A wire at the bottom of the jar was connected to a blob of tin and served as the anode, while the cathode, a loop of tin, stuck down from above. A LM317-based adjustable voltage regulator circuit was used to manage the power running through the solution. Because [The Plutonium Bunny]’s technique involves days or even weeks of very low current, he used six diodes to drop the circuit’s voltage from 1.5 V to 0.25 V, giving him around 13 mA.
His first attempt seemed to go well and he got some nice shiny crystal faces, but he couldn’t get the current bellow 10 mA without it dropping to the point where no tin was depositing. Rather than reset the experiment he made some changes to the project: he changed the solution by removing 30 ml of the electrolyte and topping it off with water. He also made a gentle agitator out of a DC motor and flattened plastic tube from a pen, powering it with another low-voltage LM317 circuit so he could get the lowest RPM possible.
With this new setup [The Plutonium Bunny] began to get much better results, proving his hypothesis that low current with a lower concentration of Sn2+ was the ticket for large crystal growth. We featured his copper crystal experiments last year and he’s clearly making good progress! Video after the break.
Continue reading “Grow Your Own Tin Crystals”
Transparent, conductive glass is cool stuff and enables LCD panels and more. But the commercial method involves sputtering indium-tin oxide, which means a high vacuum and some high voltages, which is doable, but not exactly hacker-friendly. [Simplifier] has documented an alternative procedure that uses nothing more than a camp-stove hotplate and an airbrush. And some chemistry.
Make no mistake, this is definitely do-it-outside chemistry. The mixture that [Simplifier] has settled on includes stannous (tin) chloride and ammonium bifluoride in solution. This is sprayed uniformly onto the heated glass (350-400° C), and after it’s evaporated there is a thin, strong, and transparent layer of fluorine-doped tin oxide. [Simplifier] reports resistances down in the single-digit Ohms per square, which is pretty awesome. [Simplifier] didn’t get the mix down perfectly on the first pass, of course, so it’s also interesting to read up on the intermediate steps.
Our thoughts immediately spring to masking sections of glass off and building DIY transparent circuits and panels, but we suspect that we’re getting ahead of ourselves. Still, this is an incredible early result, and we hope that it opens up the way to crazy transparent-conductive applications. What would you do if you could make glass circuits? Well, now you can, and it doesn’t look too hard.
Continue reading “DIY Conductive Glass You Could Actually Make”
Building a battery out of common household products is actually pretty simple. All that is required is two dissimilar metals and some sort of electrolyte to facility the transfer of charge. A popular grade school science experiment demonstrates this fairly well by using copper and zinc plates set inside a potato or a lemon. Almost anything can be used as the charge transfer medium, as [dmitry] demonstrates by creating a rather macabre battery using his own blood.
The battery was part of an art and science exhibition but it probably wouldn’t be sustainable on a large scale, as it took [dmitry] around 18 months to bank enough blood to make a useful battery. Blood contains a lot of electrolytes that make it perfect for this application though, and with the addition of the copper anode and aluminum cathode [dmitry] can power a small speaker which plays a sound-generating algorithm that frankly adds a very surreal element to the art installation.
While we can’t recommend that you try to build one of these batteries on your own without proper medical supervision, the video of the art piece is worth checking out. We’ve seen a few other hacks that involve blood, but usually they are attempting to use it for its intended purpose rather than as an alternative energy source.
One of the biggest challenges of traveling to Mars is that it’s far away. That might seem obvious, but that comes with its own set of problems when compared to traveling to something relatively close like the Moon. The core issue is weight, and this becomes a big deal when you have to feed several astronauts for months or years. If food could be grown on Mars, however, this would make the trip easier to make. This is exactly the problem that [Clinton] is working on with his Martian terrarium, or “marsarium”.
The first task was to obtain some soil that would be a good analog of Martian soil. Obtaining the real thing was out of the question, as was getting similar dirt from Hawaii. [Clinton] decided to make his own by mixing various compounds from the hardware store in the appropriate amounts. From there he turned to creating the enclosure and filling it with the appropriate atmosphere. Various gas canisters controlled by gas solenoid valves mixed up the analog to Martian atmosphere: 96% dioxide, 2% argon, and 2% nitrogen. The entire experiment was controlled by an Intel Edison with custom circuits for all of the sensors and regulating equipment. Check out the appropriately dramatic video of the process after the break.
While the fern that [Clinton] planted did survive the 30-day experiment in the marsarium, it wasn’t doing too well. There’s an apparent lack of nitrogen in Martian soil which is crucial for plants to survive. Normally this is accomplished when another life form “fixes” nitrogen to the soil, but Mars probably doesn’t have any of that. Future experiments would need something that could do this for the other plants, but [Clinton] notes that he’ll need a larger marsarium for that. And, if you’re not interested in plants or Mars, there are some other interesting ramifications of nitrogen-fixing as well.
Continue reading “Growing Plants on Mars… on Earth”
Micro-what? Microfluidics! It’s the field of dealing with tiny, tiny bits of fluids, and there are some very interesting applications in engineering, biology, and chemistry. [Martin Fischlechner], [Jonathan West], and [Klaus-Peter Zauner] are academic scientists who were working on microfluidics and made their own apparatus, initially because money was tight. Now they’ve stuck to the DIY approach because they can get custom machinery that simply doesn’t exist.
In addition to their collaboration, and to spread the ideas to other labs, they formed DropletKitchen to help advance the state of the art. And you, budding DIY biohacker, can reap the rewards.
In particular, the group is focused on droplet microfluidics. Keeping a biological or chemical reaction confined to its own tiny droplet is like running it inside its own test-tube, but because of the high rate at which the droplets can be pumped out, literally millions of these test-tubes are available. Want to grow hundreds of thousands of single cells, each in their own environment? Done.
The DropletKitchen kit includes an accurate pump system, along with high-speed camera and flash setups to verify that everything’s working as it should. Everything is open-source, and a lot of it is 3D-printable and written in OpenSCAD so that it’s even easy to modify to fit your exact needs. You just need to bring the science.
This is a professional-grade open source project, and we’re excited to see it when academics take a turn toward the open. Bringing cutting edge processing technologies within reach of the biohacker community is a huge multiplier. We can’t wait to see what comes out of this.