In a first for laser-driven fusion, scientists at a US lab say they have reached a key milestone called fuel gain: they are producing more energy than the fuel absorbed to start the reaction. —
Laser-sparked fusion power passes key milestone | New Scientist
Okay, okay, okay, okay, guys. Scientists at the National Ignition Facility have taken the first itty bitty baby steps towards fusion and I’m having trouble containing my excitement.
First of all, they’re using 192 laser beams, which are pointed at a gold chamber that converts the lasers into X-ray pulses, which then squeeze a small fuel pellet and make it implode and undergo fusion. That anyone ever figured out even how to do this is completely nutso.
Secondly, the lead researcher is named Omar Hurricane. I have never in my life heard a better name. He sounds like a comic book character. Please someone write a comic starring Omar Hurricane and his band of laser-wielding scientists.
And then there’s what it actually means. So far, they’ve been able to get 15 kilojoules of energy out of a fuel pellet that was blasted with 10 kilojoules. But, as The Guardian points out, much more energy is delivered by the lasers (and lost in the conversion to X-rays): “The lasers unleash nearly two megajoules of energy on their target, the equivalent, roughly, of two standard sticks of dynamite.”
Even so, this is a hugely significant tiny step forward toward recreating the clean energy production that happens in the heart of stars.
Due to a peculiarity of nuclear physics, you can release energy either by 1) breaking apart heavy atoms, or 2) forcing together light atoms. Breaking apart is called fission and forcing together is called fusion. We already know how to generate energy by man-made fission, but generating energy by man-made fusion remains an aspiration. (Of course, we know how to build bombs both ways. Nuclear and thermonuclear bombs respectively.)
Essentially, solar power is fusion, though. Because the sun is a fusion reactor, and its light lands on our planet and makes everything happen.
Oxides form on the surfaces of metals because in the atmosphere they are in contact with oxygen. The nature of these oxides affect how we think of the metals themselves. For example everyone knows that if you leave iron laying around, it will get rusty.
The oxide layer on aluminum is very thin and adheres to the aluminum, insulating it from air and protecting it from oxidizing further. This is why we think of aluminum as a material that doesn’t corrode. (By the way, this aluminum oxide is the same compound that many gems are made of.)
Anonymous asked: I saw your response to anonymous in regards to osmium and iridium. "We're big fans" you say. I'm curious. What makes you favor these elements over others? I could imagine that it would have to do with their physical properties or their history even. Perhaps their chemical reactivity. Well what makes osmium and iridium important or most fascinating?
The Director of the Clear Science Staff wrote a PhD thesis about osmium compounds. Osmium (and ruthenium, which is similar) are useful as electron transfer agents, and that was what the thesis was about. Now you know our secret.
Click here to see a few of our old posts about precious metals, osmium and iridium being two examples.
Since the oxide of osmium is volatile (i.e. it evaporates) and you can smell it, osmium is seldom used for anything practical as a pure substance. However one characteristic of osmium is that it is a very dense, hard metal. For materials that need to be hard and resistant to wear, like old school pens and phonograph needles, osmium used to be used, alloyed with other metals. Like in the Osmiroid pen tip. (photo credit)
Here on Earth we live in an atmosphere containing a reactive compound called oxygen. It’s necessary for life as we know it to exist! It also reacts with most materials. For example, metals form oxides on their outside surfaces where they touch oxygen.
The way we think of metals has a lot to do with what this oxide is like. Everyone knows that iron rusts. This is because Fe2O3 is the oxide formed on iron, which is reddish and powdery and sticks to the iron surface. On the other hand, osmium forms osmium tetroxide (“osmium with four oxygens”) OsO4 which is volatile and evaporates into the air. Since it’s a gas you can smell it, and this is why osmium has a name that basically means “a smell.”
Anonymous asked: I see that your profile picture is of crystallized osmium, very cool especially that deep blue tint. I personally have an iridium sample, the next best thing
The Clear Science Staff avatar is in fact crystallized osmium, good eye anonymous. The Clear Science Staff actually keeps a sample of osmium on a bookshelf. We’re big fans of iridium, too.
The Clear Science Staff has never liked this description of relativity, because it literally uses gravity as a metaphor to explain gravity. There are two ways to think of force fields (like gravity or electrostatics): either there is a field of forces at every point in space, or there’s no field but space is bent and distorted in an equivalent way.
There is a really great book about this by science fiction writer Rudy Rucker (or Rudolf von Bitter Rucker) called Geometry, Relativity and the Fourth Dimension.
brideyshawyer asked: Hi there, I am currently doing an issue report on MS and the medicinal use of Cannabis and I came across your article on how THC impairs memory.. I clicked on the embedded link -'A recent paper by researchers at the Louisiana State University Health Sciences Center' however, I was not able to access it.. I was wondering if you could possibly send me another link, as I think it would be really useful for my research. Many Thanks
Hi username: brideyshawyer. The Clear Science staff has fixed the link to the paper, which is here. The paper is copyrighted, so only the abstract is available at the website unless you have a subscription.
All of you clear scientists can access scientific papers like this, but it takes a little effort to figure out the best way. Often a library can get you a copy by interlibrary loan (ILL). Another way is through a university library with a subscription.
THC is the main psychoactive compound in cannabis, and has been shown effective in treating several medical conditions such as MS, chronic pain, and Alzheimer’s disease. However, it also causes cognitive side effects such as impaired working memory, lethargy, and paranoia. Especially for long-term treatment, these side effects might be detrimental for some patients. Thus there is a concerted effort to understand how THC’s cognitive side effects work and how to inhibit them.
A recent paper by researchers at the Louisiana State University Health Sciences Center shows that THC causes increased production of an enzyme COX-2. Ironically COX-2 is associated with inflammation and pain because it produces the chemical agents that cause them. Certain classes of non-steroidal anti-inflammatory drugs (NSAIDs) work by inhibiting COX-2.
The researchers found that mice given THC with COX-2 inhibitors did not exhibit the characteristic memory loss and “fear conditioning” of mice given THC alone. Importantly, the anti-Alzheimer’s benefit was also retained. This could be a major finding for medical marijuana.