“Nanocoating” could eliminate window fogging
I’m always skeptical whenever I read something about “nanotechnology.” The actual definition of “nanotechnology” is
the science and technology of building electronic circuits and devices from single atoms and molecules.
So when I read headlines like “Nanocoating could eliminate foggy windows and lenses” I immediately become skeptical, even when it’s an institution like MIT turning out the press release. The word “nanotechnology” is some sort of magnet for public attention, particularly among the geek crowd that is usually misused, often by people that should know better.
Anyway my mini-rant aside, researchers at MIT have developed a coating of “silica nanoparticles.” It’s not nanotechnology (save that it’s the right molecular size), but it is a fancy coating that will prevent windows from fogging. What’s special about this new coating is that it doesn’t have the shortcomings that other fogging solutions have: it doesn’t require UV light to function, nor does its effectiveness decrease over time. The approach to the fogging problem is pretty unique:
When fogging occurs, thousands of tiny water droplets condense on glass and other surfaces. The droplets scatter light in random patterns, causing the surfaces to become translucent or foggy. This often occurs when a cold surface suddenly comes into contact with warm, moist air.
The new coating prevents this process from occurring, primarily through its super-hydrophilic, or water-loving, nature, Rubner says. The nanoparticles in the coating strongly attract the water droplets and force them to form much smaller contact angles with the surface. As a result, the droplets flatten and merge into a uniform, transparent sheet rather than forming countless individual light-scattering spheres. “The coating basically causes water that hits the surfaces to develop a sustained sheeting effect, and that prevents fogging,” Rubner says.
I think drivers everywhere would love something like this, provided it doesn’t cost an arm and a leg. (I know I would.) Two auto manufacturers are already interested in the technology, as is the US military.
Update: Kudos to New Scientist for not using any form of the word “nanotechnology” in their coverage.
Say farewell to dead batteries
Don’t you just hate it when your laptop or cell phone’s battery runs out and you have to scramble to find a wall outlet to save your work or continue your call? Soon, you may no longer have to worry, thanks to the chemical engineers of Purdue University. At the annual meeting of the American Chemical Society today, those fine folks announced that they have developed a means by which the batteries we rely upon so much can be automatically recharged.
In their design, a credit card-sized cartridge containing hydrogen-releasing pellets would drive a fuel cell that provides charge to batteries as they are depleted. The pellets consist of compounds that produce hydrogen when reacted with water; a computer chip can monitor how many of these pellets have been used up in a cartridge and signal when a replacement is needed. Best of all, these cartridges are not only extremely portable but disposable as well; the byproducts of the reactions utilized are environmentally friendly, so used-up cartridges can easily be discarded or recycled.
Besides the obvious application in portable devices for everyone from investment bankers to Marines, the inventors mention that their device may also be considered as safe energy source for hardware in future space vehicles. Evgeny Shafirovich, a scientist who worked on the project, states:
“The Apollo 13 accident was caused by an explosion involving liquid oxygen, which is needed along with liquid hydrogen to feed a fuel cell in spacecraft. Use of chemical mixtures, such as ours, for generation of hydrogen and oxygen would eliminate the possibility of such an explosion.”
And, of course, any technology than can spare NASA further problems is a good thing.
The benefits of homeopathy questioned (again)
Back in the 1847, the American Medical Association (the AMA) was created by Dr. Nathan Smith Davis in an attempt to elevate the practice of medicine. At this time, medicine was dominated by two major schools of thought: the allopaths and the homeopaths. Dr. Davis was an allopath. It has been argued that the AMA was created to, among other things, discredit the homeopathic school of medicine. In this respect it was highly successful given that if you go to a doctor today, you aren’t given homeopathic remedies, you are given allopathic treatments.
Allopathy, in a nutshell, is the practice of combating illness with opposites. If you have an infection, you are given an antibiotic. If you have cancer, you receive radiation or chemotherapy to kill the cancerous cells. Largely, these treatments work: people have longer life spans today than they did 100 or 200 years ago. We’ve come a long way in the study of medicine, but there are some things that medicine simply has no answer for. Or if there is an answer, it is not an optimal way of dealing with a medical condition. Witness things like oral steroids like prednisone and Medrol. Long-term use of these types of medications is not healthy, and often the side effects can be worse than the condition they’re being used to treat. The same is true of the myriad irritable bowel diseases like Crohn’s disease, various forms of colitis, etc: these diseases don’t have treatments that are especially effective without doing drastic things like suppressing the immune system or removing parts of the intestines.
For a long time, there has been an “alternative” movement in medicine. It has become popular in recent years, and the fact is, this school of thought has been around for quite a long time. These natural remedies are often looked down on by those in the medical profession, especially doctors. I think this is a mistake, for a number of reasons that I will expound upon in a moment. First, I want to explain the principle behind homeopathy.
Homeopathy essentially amounts to taking a substance that would normally cause irritation in the body, and diluting it many times over. The idea is that by diluting the substance and then introducing this diluted solution into the body, the body will be able to effectively combat whatever illness or irritant is ailing you. Basically, fighting like with like. This is the exact opposite of the traditional allopathic medicine that is mainstream today.
One of the allopaths’ arguments against homeopathy is that the substance is diluted so much, all that’s left is water. Contrary to “real” science, water molecules cannot “absorb” the properties of an irritant and still be water. It would be a water + something else solution. But all that’s present is this water, there is nothing else. So what you’ve got from a chemical point of view is water being used to treat everything from poison ivy to stomach cancer.
I stated in the very first post here on polyscience.org that I was a pharmacy student. As such, most of my schooling is done on the allopathic side of things. We study the drugs that are used today. Slowly, though, the curriculum is changing; we’re learning about herbs and probiotics and even homeopathy. In general, I prefer a good allopathic remedy that I know is going to work, but I hesitate to question the efficacy of alternative therapies for many reasons. Perhaps the most blindingly obvious one is that doctors, pharmacists, and even the drug companies simply don’t know why some drugs work. This is usually due to an incomplete understanding of the specific physiology underlying the body process that we’re trying to alter. It would seem reasonable to me, then, to not dismiss alternative medicines and therapies out of hand. One of these is homeopathy, despite it not making “scientific” sense. Relegated to the ignoble position of “placebo,” subject to ridicule from layperson and medical professional alike. But something being deemed “placebo” isn’t necessarily a bad thing. Any medical professional worth his salt will tell you that getting better is often simply a state of mind. “Simply,” of course, being anything but simple. Twenty years ago, it was not uncommon for a doctor to literally write a prescription for a placebo. The patient would then take this prescription to the pharmacy where it would be filled. The capsules dispensed were usually filled with lactose — a filling agent used to fill the extra space in a capsule for a custom-compounded medication. And the patients were happy, and usually got better. Not all the time, of course, but most of the time.
This brings me to the catalyst for this post. The Lancet is probably the most prestigious medical journal in the world, and recently they’ve once again shot down the benefits of homeopathic therapy. They might be right,I don’t know; it’s impossible to know, and the researchers have even acknowledged this.
Professor Egger said: “We acknowledge to prove a negative is impossible.
“But good large studies of homeopathy do not show a difference between the placebo and the homeopathic remedy, whereas in the case of conventional medicines you still see an effect.”
What I do know, however, is that given our incomplete understanding of the human body, dismissing all alternative therapies out of hand is a mistake, and I think that over the next 100 years, we allopaths will discover this. I’m not saying that homeopathy is effective or if it’s “just” the placebo effect, but I do think that we should continue to investigate “alternative” therapies — homeopathy included, even if it’s just to disprove their efficacy. Disproving something definitively is never a waste of time or money.
A chemical clothes drier
“Better living through science,” as they say. In this case, through chemistry. Researchers at the University of Florida have come up with a novel way to decrease drying times for loads of laundry. The compound is called dioctyldecyldimethyl ammonium bromide (‘”We call it dodab,” Carter said’ — one can hardly blame them), and it works by decreasing surface tension in the water.
Those of you familiar with surface active agents (surfactants), like soap, will already know that adding such agents to water decreases the surface tension. For example, if you filled up a cup of water to the point where the water is higher than the edge of the cup, and then added the tiniest bit of soap, this water over the brim would spill down the sides of the cup because the surface tension was decreased. Laundry detergent does the same thing, but this “dodab” compound decreases the surface tension even more. The ramifications could be huge.
Clothes dryers accounted for 5.8 percent of U.S. residential electricity in 2001, according to figures from the Energy Information Administration, costing $5.6 billion. “If you could cut that down by 10 percent, that would have a important impact on the big picture,” said Jonathan Cogan, an EIA spokesman.
Carter says they can do even better: “I believe that with further research, we could cut drying times by between 30 and 40 percent.”
30 to 40% is pretty impressive is pretty impressive in terms of money, and time. If drying time could be cut down by that much, my clothes might actually be dry by the time the wash cycle is finished, and if that happened, I might actually fold said laundry the same week that it got washed. If you’re anything like me, you start doing laundry with the best intentions and then never finish it because you got sidetracked by something else, or sitting and staring at the wall just seemed like a better idea… now if only they could make something that would fold my clothes and put them away for me, I’d be all set.
Four scientific societies oppose Bush’s intelligent design stance
Earlier this month, I reported on how President Bush wants to teach “intelligent design” alongside evolution in public schools. Now, four separate scientific societies have come out against Bush’s stance. The American Society of Agronomy (ASA), the Crop Science Society of America (CSSA), the Soil Science Society of America (SSSA), and the American Chemical Society (ACS) have each come out in favor of teaching evolution in classrooms in the US.
A position statement was unanimously passed by the first three organizations I listed. Their position echoes my sentiments expressed in my previous post on the subject. Here’s an excerpt:
Intelligent design is not a scientific discipline and should not be taught as part of the K-12 science curriculum. Intelligent design has neither the substantial research base, nor the testable hypotheses as a scientific discipline. There are at least 70 resolutions from a broad array of scientific societies and institutions that are united on this matter. As early as 2002, the Board of Directors of the American Association for the Advancement of Science (AAAS) unanimously passed a resolution critical of teaching intelligent design in public schools.
The intelligent design/creationist movement has adopted the lamentable strategy of asking our science teachers to “teach the controversy” in science curriculums, as if there were a significant debate among biologists about whether evolution underpins the abundant complexity of the biological world. We believe there is no such controversy.
The fundamental tenet of evolution -– descent with modification -– is accepted by the vast majority of biologists. The current debates within the research community deal with the patterns and processes of evolution, not whether the evolutionary principles presented by Darwin in 1859 hold true. These debates are similar to those surrounding the relativistic nature of gravitational waves. No one doubts the existence of gravity just because we are still learning how it works; evolution is on an equally strong footing.
The discussion of life’s spirituality is most appropriate for philosophy or religion classes. It is a mistake to conclude that reluctance to incorporate spiritual questions in science classes runs counter to the cherished principle that vigorous challenge is vital to the scientific method.
[...]
…President Bush, by suggesting that we use intelligent design as a scientific counterpoint to the teaching of evolutionary biology, is unwittingly undermining the scientific method at its core. This is most unfortunate in an era when U.S. students are already lagging behind their international peers in science education.
(Emphasis mine.)
The fulltext of a separate statement posted by the ACS is available on the ACS website (PDF), and it expresses sentiments similar to those above.
If your science education was anything like mine, the topic of how we got here was glossed over. Vague references to “millions of years ago” and “the Jurassic period” and “the first Ice Age” were occasionally made, but we were never taught the ins and outs of evolutionary theory. Instead the school system opted to leave out this part of our education. As a result, I know next to nothing about evolutionary theory except the bits and pieces that I’ve learned from my independent reading, and journey through higher education. I went to a very good school, but they wouldn’t touch evolution with a ten-foot pole. I’m curious how many other Americans had an education like mine?
Tokyo opts to water its streets
In an effort to combat rising city temperautres, Tokyo has turned to a neglected custom called uchimizu, which is the sprinkling of water on the ground to lower air temperature.
This latest attempt to bring down summer temperatures that have been hovering in the 40s Celsius involves pumping up the water that seeps into the metro system and spraying it from the kerbside[sic] onto the road surface. A water-retentive coating stops the water from draining away, and evaporation does the rest.
At the test site, directly outside Japan’s parliament building in central Tokyo, a solar and wind-powered pump forces the subway flood water into high-pressure sprinklers that spray it over a 350-metre stretch of road. Recently, the researchers managed to cool the road surface – which often reaches up to 60 °C during the summer – by 10 °C, and the air above the road by 1 °C.
(For the Americans out there — myself included — 40°C is 104°F; 60°C is 140°F)
In recent years, the temperature of Japan’s cities has outpaced global warming by a factor of 4. Temperatures in Tokyo have increased by an average of 3°C (~6°F) compared to 100 years ago. Revisiting uchimizu has caused pavement temperatures to drop by 10°C, and the air temperature to drop by 1°C — no small feat.
A battery powered by urine
I’m having flashbacks to seventh grade science class (one of my favoritest classes ever), and the voltaic pile that we made. Scientists have recently created a battery that is powered by urine, similar to the original voltaic piles, only miniaturized.
I’m not quite sure why this is so amazing given that it’s essentially technology from the 1700s. The device creates electricity via an electrochemical reaction: one side of the paper gains electrons (oxidation) and one side loses electrons (reduction). This redox reaction creates a small amount of voltage, which can be used to power small medical devices such as diabetes monitors. Urine contains glucose, the concentration of which can be used to determine the level of sugar in the blood.
The unit is much smaller than a traditional voltaic pile, but it functions on the same principle:
The battery unit is made from a layer of paper that is steeped in copper chloride (CuCl) and sandwiched between strips of magnesium and copper. This “sandwich” is then held in place by being laminated, which involves passing the battery unit between a pair of transparent plastic films through a heating roller at 120ºC. The final product has dimensions of 60 mm x 30 mm, and a thickness of just 1 mm (a little bit smaller than a credit card).
Writing in the Journal of Micromechanics and Microengineering, Lee describes how the battery was created and quantifies its performance. Using 0.2 ml of urine, they generated a voltage of around 1.5 V with a corresponding maximum power of 1.5 mW. They also found that the battery performances (such as voltage, power or duration) may be designed or adjusted by changing the geometry or materials used.
I guess the more things change, the more they stay the same?