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Hemp Fibers Make Better Supercapacitors Than Graphene
biodata (1981610) writes "BBC News is reporting findings published in the journal ACS Nano by Dr David Mitlin from Clarkson University. Dr. Mitlin's team took waste hemp stems and recycled the material into supercapacitors with performance as good, or better, than those built from graphene, at a fraction of the raw materials cost. "We're making graphene-like materials for a thousandth of the price - and we're doing it with waste. The hemp we use is perfectly legal to grow. It has no THC in it at all - so there's no overlap with any recreational activities," Mitlin says.
This is potentially exciting... no pun intended :-)
:)
The article abstract says:
The nanosheets are ideally suited for low (down to 0 C) through high (100 C) temperature ionic-liquid-based supercapacitor applications: At 0 C and a current density of 10 A g–1, the electrode maintains a remarkable capacitance of 106 F g–1. At 20, 60, and 100 C and an extreme current density of 100 A g–1, there is excellent capacitance retention (72–92%) with the specific capacitances being 113, 144, and 142 F g–1, respectively. These characteristics favorably place the materials on a Ragone chart providing among the best power–energy characteristics (on an active mass normalized basis) ever reported for an electrochemical capacitor: At a very high power density of 20 kW kg–1 and 20, 60, and 100 C, the energy densities are 19, 34, and 40 Wh kg–1, respectively. "
Which possibly suggests that the materials are suitable for indoor use (but not in cars unless you happen to operate in a non-freezing climate) which could have some very practical applications. Solar panels are becoming attractive and I'd like a storage bank but would like to avoid batteries because of the slow charge, expense, and maintenance. A super capacitor, of course, is attractive. Off the top of my head, I don't know what the power density of this type of capacitor is relative to lead acid deep cycle batteries. Still, I smile though
This will give new meaning to the term 'magic smoke'.
( http://en.wikipedia.org/wiki/M... for those that don't know)
Have you ever made hemp fiber supercapacitors...on weed?
"The hemp we use is perfectly legal to grow."
Yeah, if you're properly affiliated with a university or state department of agriculture, are doing it for research purposes, and have agreed to all of the terms and conditions that the feds and your local state require. If you or I try to do it commercially, it's a federal felony.
What about basket weavers, you insensitive clod!
Sorry, but every cannabis sativa plant, whether of the recreational, medicinal, or hemp varieties produces some THC. Granted, hemp is a miniscule fraction of a percentage THC, but it does have THC.
I do not fail; I succeed at finding out what does not work.
Dang it folks, I left the farm to be an electrical engineer and it keeps following me! I ran away from the farm for a reason, and bailing twine was wrapped all around it.
Now we are going to be making capacitors from bailing twine? NOOOOOO!! I won't do this again!
I have to retire before they start sending me out to pickup packages of dried grass and haul them to the barn again.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Marijuana. Is there anything it CAN'T do?
But, can it be converted into a bong?
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
A supercapacitor is not superconducting; it just stores a lot of charge.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
https://www.youtube.com/watch?...
The hypocrisy of the government is retarded.
--
"It is the government proselytizing it is propaganda. When it is people promoting it, it is outlawed."
Well, every technology has bugs and birthing pains. Keep working at it, and perhaps you can graduate to a better class of hemp, Mr. Mitlin.
I've fallen off your lawn, and I can't get up.
You can be forgiven for thinking this, since the law changed very recently. Several states had passed industrial hemp bills that were void until the Federal government acted. They finally acted. Note that some of the industrial hemp states do not allow recreational. I haven't checked to see if they all allow medical. Thus, it's legal to grow industrial hemp in California, but recreational marijuana is still an infraction/$100 fine for less than on oz., criminal for more than an ounce, etc. I don't know what the regs are for joe blow growing industrial hemp. I don't think I'm going to try since it would attract unwanted attention for obvious reasons.
... capacity for any recreational activities.
It little behooves the best of us to comment on the rest of us.
How about this recently published gem: Preparation of energy storage material derived from a used cigarette filter for a supercapacitor electrode .
but love science when it finds uses for hemp
Because with large scale hemp agriculture, you can always sneak in a few rows of 'the good stuff'.
Have gnu, will travel.
Administrator: What are you guys doing in the lab with all those plants?
Undergrad lab assistant: Testing them for use as supercapacitor electrodes. Yeah. That's the ticket.
Administrator walks away satisfied.
Have gnu, will travel.
Experimenter bias?
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
The hemp we use is perfectly legal to grow. It has no THC in it at all - so there's no overlap with any recreational activities," Mitlin says.
A shame, isn't it?
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
voltage?
there's more to it than just Mary Jane. You don't think the cotton lobby has noticed the wonder material that is hemp?...
Hi! I make Firefox Plug-ins. Check 'em out @ https://addons.mozilla.org/en-US/firefox/addon/youtube-mp3-podcaster/
You wouldn't want to though. Your marijuana plants would end up getting cross-pollinated and the quality would go to hell. No one would want to buy the crap. That and cultivating the plants indoors in a more controlled environment is going to provide a much better yield.
Care to share pointers to the dangers of MJ use? If possible some where it's anyone's business but the person's who consumes it. Note: It's NONE of your business if someone wants to off himself in any way he likes.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
So they are just like... everybody else?
Any insufficiently advanced magic is indistinguishable from technology.
Marijuana doesn't have the same dramatic effects as meth, and there are people who are long-term users who suffer very few side effects from this drug. There is however a small chance that it can lead to temporary or even permanent psychosis. There is still some debate over this issue, but I can assure you it's quite real.
http://www.sane.org/informatio...
http://medicalmarijuana.procon...
A while ago I spent some time in a mental facility and one of the patients there was that unlucky 1 in 700,000 who was vulnerable to the psychotic effects that marijuana could cause. He was a good student who was just starting university. Intelligent, articulate, and with excellent grades - he had good prospects for a long and happy life.
His mother worked as a nurse at that hospital so she could spend time with her son, and I received this information directly from her. At uni he tried marijuana, just a few times. I get the impression he was just a typical uni kid enjoying his new freedom and he started to smoke it because his new social circle were smoking it. Pretty typical stuff. He had an adverse reaction (I think over a short time period of maybe week or so) and had to be hospitalised due to psychosis.
By the time I met him, he had been in hospital for 12 years. He had no teeth left, since he couldn't look after them they had to all be removed. He was heavily medicated but was still liable to fits of anger and hitting other patients for something simple like sitting in his chair. He was barely able to speak and never managed more than a couple of mumbled, often unintelligible words. There was a rec room where we could watch a TV which was behind a plexiglass panel we needed to lift up to change channels. He had a tic that meant every 1-2 minutes he needed to get up, walk to the TV, life the plexiglass, run his hand over the top of the TV, then sit down again. He might do this 100+ times in a day.
While it's easy to think there's no dangers using marijuana, and admittedly, they are few and low - it's not totally without cost or risk. This man will spend the rest of his short life in that mental institution, unable to read, play games, go outside, speak to others, share friendships or talk about the good old days. He will never experience any of the myriad of things that you and countless others can - and that is directly attributed to a fairly small quantity of weed he smoked - he wasn't trying any other drugs at the time.
Certainly, he had a disposition towards this happening, but it was marijuana that pushed it over the limit and completely fucked his entire life.
We have a decent welfare system and free hospitalisation in Australia, so he is getting the care he needs. You could argue that as taxpayers who are shouldering that cost we do get a say in whether people consume the drug or not...but, I'm not going to bother with that argument, it's not the important one.
Enjoy the smoke if you can amd avoid it if that's that you prefer. Just bear in mind, however small, there is a chance of psychosis that may in same rare cases be permanent - and weed is a known contributor to this condition.
Role your dice, move your mice.
All those moments will be lost in time, like tears in rain.
1/700,000 has an adverse reaction to marajuana
how many people in the US can die from eating a peanut? almost no non-essential substance is innocuous to everyone.
but love science when it finds uses for hemp
Because with large scale hemp agriculture, you can always sneak in a few rows of 'the good stuff'.
No, you can't - although the belief that you can is apparently what has kept the hemp business shut down in the U.S. for 80 years (and led to Governor Arnold to veto a hemp cultivation measure in California.
The cultivation patterns are completely different. The hemp crop is grown in dense plantings that lead to tall stalks and few leaves, and then the crop is either harvested before it flowers (if an all-fiber farm) or is allowed to go to seed (if hemp seed is also harvested).
Either way there is no way that a successful drug crop, however small, can be snuck in there. (Not so drug cannabis and, say, field corn though - hiding pot among corn is an old trick).
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
oh no, soon our computers will be confused and forgetful ..
If I put a supercap made of organic hemp into an oven at 105C for 5000 hours, what's left when I am finished? It is still a supercapacitor or is it a small metal can full of organic goo?
to see if it is possible to get both ends of the world?
But if this is 1/700,000 -- you are below the danger level of side effects to Aspirin.
Peanuts are legal and they can potentially kill more people.
Now we might put a warning label so people can look for the side effects, but this doesn't seem like a threat above "slipping on rubber ducky". Other than paranoia, this is about the third time I've heard of a person almost destroyed by MJ. There are many legal things that are far more dangerous.
>>"ad space available -- low rates!!!"
I remember seeing a news story about a train conductor who "took marijuana and caused a deadly crash." They also mentioned, almost as a footnote near the end of the story that there were nearly 24 empty Miller Lite beer cans.
So I think we can't rule out something else that could have caused the malady.
>>"ad space available -- low rates!!!"
I see a distinct lack of "evidence" in your post.
Great. It's in no way distinguished from the post which I was addressing, then. Providing a link doesn't mean one has provided meaningful evidence.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
A while ago I spent some time in a mental facility and one of the patients there was that unlucky 1 in 700,000 who was vulnerable to the psychotic effects that marijuana could cause.
As compared to:
As many as 600,000 Canadians (1 - 2% of the overall population) are thought to be at risk of anaphylaxis stemming from food and insect allergy.
-- http://www.aaia.ca/en/anaphyla...
So what's you point exactly? That marijuana is approximately 10,000 times safer than food?
It sounds more like it was directly attributable to his existing medical condition which could have been triggered any number of ways, such as sleep deprivation, poor diet, or drinking too much...
Try and grow hemp anywhere near me and I'll cut it all down.
It would ruin my sensi.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
So I decided to fact check:
http://www.peanut-institute.or...
"The National Institute of Allergy and Infectious Disease (NIAID) has reported that approximately one in 90 people in the United States, or 1.1%, have a tree nut and/or peanut allergy and the Food Allergy and Anaphylaxis Network (FAAN) has stated that it is about 0.6% each."
and
http://health.howstuffworks.co...
"Somewhere around 150 to 200 people die in the U.S. each year because of food allergies. It's estimated that around 50 percent to 62 percent of those fatal cases of anaphylaxis were caused by peanut allergies."
So lower bound is roughly 75 people each year actually die, not just have a permanent psychosis, to peanuts.
Compared to 1/700,000 having an adverse reaction to marijuana.
"Someone needs to talk to the tree of liberty about its ghoulish drinking problem." by ohnocitizen
He had no teeth left, since he couldn't look after them they had to all be removed. He was heavily medicated but was still liable to fits of anger and hitting other patients for something simple like sitting in his chair. He was barely able to speak and never managed more than a couple of mumbled, often unintelligible words. There was a rec room where we could watch a TV which was behind a plexiglass panel we needed to lift up to change channels. He had a tic that meant every 1-2 minutes he needed to get up, walk to the TV, life the plexiglass, run his hand over the top of the TV, then sit down again. He might do this 100+ times in a day.
You understand that the very heavy effects that you describe are most likely the results of the heavy medication he's on, much more than of his psychotic trouble or marijuana?
Read Roger Gentis, it's a bit old now but still relevant...