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Comment Are there better uses for this technology? (Score 1) 109

As I recall compressing and storing hydrogen is a very expensive process. One problem is that hydrogen likes to destroy most metals. Any piping, compressor, or container must be made of expensive metals or lined with glass or something.

I recall reading several articles over the years about the Navy working on a process to turn hydrogen and CO2 into hydrocarbon based fuels. The hydrogen would be from cracking water. The CO2 that is dissolved in the water would be extracted for the process. If this fuel cell technology can improve on the process of producing hydrogen from water then the seawater to jet fuel process could be more viable.

I might be mistaken but hydrocarbon liquids can store hydrogen in a much smaller space than any compressed gas. I recall that not even liquid hydrogen can not beat fuel oil on hydrogen per volume. If this is true then it would seem that storing the hydrogen as a fuel oil might be more viable than compressing into heavy and expensive tanks. There's a few bonuses for storing the hydrogen as a hydrocarbon, even if it means cracking the hydrogen off again to run the fuel cell to produce electricity. A liquid hydrocarbon can fuel cooking stoves, trucks, battle tanks, helicopters, and even generators. Hydrogen can only really be used in a fuel cell.

It's interesting that this can store energy as a hydrogen gas but how does this compare in cost, weight, and volume to more traditional systems like lead-acid batteries? The military might have needs that make this viable for them but in a non-military environment this does not seem practical at all. The government is willing to spend a lot of money to save on things like time, space, and weight, but they have their limits. Unless they can make a case for civil uses I doubt this will go far in the military.

Comment Re:Sounds good... (Score 1) 109

"For places where water is in short supply like California, why isn't every power plant being built near the sea, where they can use seawater for cooling? It'll have to be a two-stage cooling circuit with a heat exchanger to prevent corrosion from affecting power generation systems. But that's already what's used in nuclear plants so there's no new engineering which needs to be developed there. Do this and 1/3rd the energy from burning coal, oil, or nuclear can go into generating electricity. The remaining 2/3rds of the energy can go into desalinating seawater. "

The reason I heard this doesn't happen is because the waste heat is not at a high enough temperature to make desalination affordable. The resulting water is not boiling hot like what is needed for evaporative cooling, just merely lukewarm.

What might change this is the use of high temperature nuclear reactors like liquid fluoride thorium reactors, or LFTR. A LFTR can reach temperatures where the final output is hot enough to boil water. One might add an additional turbine stage to turn this energy to electricity but at that point the percentage of energy retrieved is so small that it would likely not be profitable, making clean water would make more economic sense. Other uses for this heat could be heating for buildings or a number of industrial uses.

Water cooled power plants like coal, natural gas, and solid fuel nuclear reach temperatures of about 300C. LFTR could get to 600C or 800C which makes desalination off that waste heat possible. The primary turbines would not be steam like a coal plant but open loop air or a closed loop gas.

There are other benefits to LFTR besides making water desalination and electricity production relatively easy and profitable. A primary benefit is that it cannot melt down like a solid fuel reactor, it is very safe. LFTR can also produce a lot of other beneficial byproducts like medical radioisotopes, without the undesirable byproducts like weapon grade plutonium. It will make plutonium but of a quality that is nearly useless for weapons but very valuable for energy.

Comment What of political contributions? (Score 1) 182

In the USA there is (or at least was) a cap on how much a person could contribute to a political campaign. If there is a law that all transactions must have the option of payment in cash then what happens to the caps on political contributions? I suppose there could also be a law that any payment to a political entity must have record keeping to prevent... what would you even call this? Is it "abusive" contributions?

Personally, I do not believe there should be a cap on political contributions. I suppose it is possible on some level that a political entity might abuse this and theoretically "buy" an election. What I fear more than bought elections is a candidate or lobbying effort being silenced because of some accusation of record keeping abuses. The abuse of a government entity regulating how I, or anyone else, might choose to spend my money on supporting a policy or candidate frightens me more than some billionaire buying up all the billboards, TV ads, and radio time.

Let people speak freely, and that means giving money to any lobby effort or political campaign they choose. Paying in cash is certainly one way to make that easier. If I walk into John Jackson's campaign offices with a grocery bag of cash to fight the campaign of Jack Johnson then no campaign contribution limits should allow the government to arrest me for doing that.

Comment Re:OK, science is settled, now do something about (Score 1) 554

On a deaths per joule comparison nuclear power wins over them all by a large margin. Do you think that people don't fall from windmills and rooftop solar panels? People die.

Also, people in Fukushima got more radiation by flying from the area than if they stayed. Chernobyl was barely a first generation reactor, it didn't have modern safety features like a containment dome. The answer to this problem is not to stop building nuclear power plants but to build more so that we can afford to decommission power plants like those at Fukushima.

Japan shut down all their nuclear power plants for a while but were forced to restart them. This is because without nuclear power they had to resort to dirty, unsafe, and expensive coal. Wind, solar, and tidal power would cost us more in money and lives then even building more Chernobyl type power plants.

Thankfully we don't have to build another Chernobyl, Fukushima, or Three Mile Island to keep the lights on. We can build fourth generation nuclear power, reactors that are safer, cheaper, and more reliable than even the already very safe, cheap, and reliable first and second generation reactors that caused us so much panic.

At a minimum we should at least have some government funded research in nuclear power like we have government funded research in wind, solar, and tidal. We have much to learn on nuclear power, and claiming we cannot harness that power safely is like claiming we should not invest in Tesla motors because the Model T and Pinto were unsafe. A modern nuclear reactor would not be built like those at Fukushima.

We can build much better nuclear power plants but we've held ourselves back because of failures of completely unrelated designs. Failures that, BTW, involved very little cost in lives and cleanup when compared to the alternatives.

Comment Re: The best part about this... (Score 1) 128

A possible counter argument is that this person that is black listed from the private sector because of a past with the FBI could then find work with NOAA predicting hurricanes, DARPA working on lots of stuff, NASA doing astronomy and physics, or a number of public universities doing just about anything.

Blacklisting someone because of a past with the FBI might be a dick move but perhaps we could let them redeem themselves by doing something beneficial for society for a few years before we drop them from the list.

Comment Re:Asinine (Score 2) 128

The federal marshals work for the judicial branch. Their mandate is to search for escaped prisoners and such, people that have already been convicted of a crime. The FBI is tasked with the enforcement of federal laws, which has some overlap with escaped prisoners and such but the federal marshals don't have much overlap with what the FBI does.

The FBI not having arrest powers is an interesting idea. Let the FBI investigate but once it comes time to arrest then let the local sheriff perform the arrest. This works on areas within a state boundary but falls apart in federal districts, territories, and so forth. These areas could have a local equivalent of a sheriff for the purpose of enacting arrests but then they'd be employees of the FBI in every way but name.

If you want to talk about pruning federal law enforcement powers then I propose doing away with the DEA and BATFE. These are enforcement agencies that have powers that overlap completely with the FBI, so roll them into the FBI and do away with the separate agencies. An FBI that is busy with tracking down child molesters, kidnappers, murderers, arsonists, and what not might not then bother with handing guns to drug dealers like the DEA and BATFE has done.

Comment OK, science is settled, now do something about it (Score 1) 554

Let's assume that the claim is true, we've studied the problem sufficiently to the point that we understand the problem and therefore our need for people to work on climate models and so forth is diminished. Let's also assume that while we can do away with some climate studies we cannot end it completely since we will need to monitor progress and guide policy.

So, what should we do? It seems that many of the people in positions of power talk a lot about doing an "all of the above" approach. This means doing anything and everything that can possibly reduce our carbon output. We've seen PSAs telling us to turn off the lights in rooms we aren't using and to turn off the tap while brushing our teeth. We've seen government subsidies for solar panels, windmills, corn ethanol, and electric cars. What's missing here? IMHO, we've got government support for every tactic to fight global warming except the one that has the best chance to reduce our carbon output with the least cost and smallest impact on our daily lives.

That solution is nuclear power.

Any politician that claims that the government needs to fund this and support that and ignores nuclear power is not serious about the problem. This tends to lead me to think that global warming is not the problem that they claim. It also doesn't help that they'll chide me for driving my light truck while they fly in jet planes all over the world. They have a meeting of the world powers on how to combat our carbon output, flying all these people there to meet, and all they've agreed to do is meet again in five years to talk about it some more.

I thought global warming was the greatest threat this nation, and this planet, has ever faced. Yet these people don't seem to be acting like it is.

I'm not convinced that global warming is a problem based only on the actions of the people with the ability to have the greatest effect on the carbon our modern society produces. If these people were convinced on the problem we faced then we'd see them talking about nuclear power. If they cannot bring themselves to bring up nuclear power as part of the "all the above" strategy to fight global warming then I can only conclude that they fear losing votes more than they fear the end of civilization. A true believer would not be concerned about the next election, they'd be concerned about the next century.

Comment seawater to jey fuel sounds better (Score 1) 156

The US Navy has been working on a process that derives hydrogen and CO2 from seawater as feedstock for synthesis of hydrocarbons. Methanol is nice but hydrocarbons are better. We know how to store, transport, and efficiently burn hydrocarbons. We don't know as much about methanol.

Also, it sounds like the seawater to jet fuel process is in its final stages of development, needing only enough funding to prove its viability. This air to methanol process sounds like its purely theoretical now.

Comment Re:Why you should care about 3D printed handguns (Score 1) 295

I meant "expensive" in a relative sense. Other items that would need similar precision to function, like a clock or socket wrench, do not have as many moving parts and therefore can be obtained with what someone might consider pocket change. It is a tool that requires a relatively high level of precision to function as intended but since it is made in such high quantity the price is quite low.

A $100,000 machine that can print out a $30 socket set or wall clock is not very impressive. If that same machine can print out a Model 1911 pistol that can fetch easily $1000 on the open market then you will get people's attention. If that device can print out a shiny new M1911 in a week then it will pay for itself in a few years. If it can print one out in a day then it can pay for itself in months.

Comment Re: Militant Slashdot (Score 1) 295

The term "assault rifle" is a military designation for a type of small arm. An assault rifle is a rifle chambered in a cartridge with a range and/or power less than a "battle rifle" but greater than a typical handgun. Such weapons typically have a selector switch that enables semi-auto or three round burst functions. Some early weapons of this type were capable of switching between full-auto and semi-auto but this is rare today. Some common cartridges for such weapons are 5.56 NATO, .30 Carbine, and 7.62x39mm.

For clarity a "battle rifle" is a relatively large caliber rifle, typically about .30 caliber, with semi-auto capability. A "machine gun" is both a military designation and a BATFE legal designation with slightly different meanings. In the military a machine gun is a weapon capable of firing battle rifle cartridges in fully automatic mode. Military machine guns may have a burst or semi-auto feature but this is rare. As defined by the BATFE a machine gun is any firearm capable of firing more than one cartridge by a single action of a trigger. To the BATFE a worn out double barrel shotgun that fires both barrels with one trigger pull is a "machine gun", as is any military designated "assault rifle" due to the three round burst feature. To the BATFE the caliber of the weapon is not part of the machine gun definition, any cartridge will do.

The term "assault weapon" (as opposed to assault RIFLE) is a nearly meaningless term. It's definition varies from state to state and from time to time. All it really means is "what we want to ban today". The weapon used at Sandy Hook did not meet the definition of "assault weapon" in Connecticut law even though it may have met that definition if it were in California. Some common features to the definition to an "assault weapon" are some rather silly features like bayonet lugs (because drive by stabbings is a problem I guess) or threaded barrel ends (used to attach safety devices like report suppressors and flash hiders but the powers that be focus on the ability to attach a grenade launcher).

To add further silliness to all of this is the term "personal defense weapon". This is a term that also has several meanings depending on who you ask. In the military a PDW would be something like a P90, a weapon that fires pistol caliber cartridges in three round burst or semi-auto and comes standard with a 50 round magazine. To the Department of Homeland Security a commonly used PDW is the M4 Carbine. To the military the M4 Carbine is an assault rifle. To the BATFE the M4 Carbine is a "machine gun" if capable of three round burst, or a "short barreled rifle" if semi-auto only. Of course most every state in the USA would classify this as an "assault weapon".

Interesting isn't it? The same weapon, in this case the M4 Carbine, gets different designations not based solely on who is holding it at the time. In the hands of a Marine it's an "assault rifle". In the hands of a DHS agent it's a "personal defense weapon". In the hands of the people that pay their salary with taxes it can be a "machine gun", "assault weapon", "short barreled rifle", or (my favorite) an "offensive weapon".

What is an "offensive weapon"? Hell if I know. Best I can tell is that it is something that some politicians decided offended their sensibilities at some point in the past, therefore they banned their possession by anyone not earning a government paycheck. The term "offensive weapon" has just about the same meaning as "assault weapon". I expect that given time the term "assault weapon" will be discredited enough that the term "offensive weapon" will regain popularity with the powers that be that wish to disarm us.

Comment Re:Why you should care about 3D printed handguns (Score 1) 295

That's some fucking retarded reasoning

It's no different then the reasoning on why the President said we should go to the moon. We did it because it was hard. Making a handgun is not hard, many people do it. Making a handgun by 3D printing is hard, and is as suitable of a test of the technology as building any of a number of items.

Perhaps you would like to expand on why you think this reasoning is "fucking retarded"? Perhaps you could also propose a more suitable item to manufacture as a test of 3D printing technology?

Comment Re: Militant Slashdot (Score 4, Insightful) 295

Apparently so since much of the desire to ban these weapons was the result of gang warfare during Prohibition.

Funny that, history repeating itself. Alcohol prohibition resulted in violence not seen before it's implementation. Now today people don't shoot each other over alcohol because it is available at nearly every convenience store with nothing more than proving you are an adult and have the ability to pay for it.

Perhaps we would not have "drug addled scum burning down your cities" if these drugs were not banned. Just a thought. It appears that there are at least some people that agree with me given that a number of states in the USA have legalized marijuana with no real threats to society to show for it.

Also, how does banning possession of a handgun supposed to prevent "drug addled scum" from setting the city on fire? I do know that even drug addled scum have a nearly instinctual fear of getting shot if they threaten to burn down someone's home or business. It would seem to follow that by removing the handguns, and therefore diminish the homeowner's ability to defend their home, would embolden the scum to burn the world down.

Gun control is not crime control. You control crime by controlling the criminals.

Comment Why you should care about 3D printed handguns (Score 2) 295

I've read a lot of posts of people exclaiming 3D printed handguns a waste of time, or an effort to expand one's "manhood" by building weapons. I've read an article on 3D printed handguns before where the creator was asked why they chose to print a handgun of all things. In this case it was a 3D printed Model 1911, printed using a number of direct printing metal techniques but the answer to this question stuck with me and I believe answers the question quite well.

The creator of this 3D printed handgun explained the choice of printing a handgun this way. People understand what a handgun does and what it is used for. People understand that a handgun is a device with many intricate parts placed under considerable wear, pressures, and so forth. Whatever a handgun is made from must be durable. A handgun built with poor tolerances is not likely to function. A handgun is an expensive machine, not something one can typically purchase on a whim. It is also something that can be manufactured within the size limits of their machines.

Someone could 3D print a clock, for example, to show how a useful item can be built with amazing precision with a 3D printer. To show how a 3D printer can make something that is durable could mean printing a carpenter hammer, or anvil. Perhaps building an adjustable wrench, socket set, or any of a number of tools that need to hold up to extreme stresses and tight tolerances would show the capabilities of a 3D printer. Those are also rather mundane and perhaps a number of people that do not use tools regularly will not understand the difficulty in building such a tool with a 3D printer. These are also tools that do not have much value since people can buy these items relatively cheaply most anywhere.

People choose to 3D print a handgun because it is hard to do. Someone successful in this has then demonstrated their ability to build any of a number of more common and mundane items we use every day. It also doesn't hurt that 3D printed handguns makes politicians nervous and gets clicks on the internet.

Go print a clock and see how many clicks you get on your website, then print an anvil and do the same. Now print a handgun and hope that you've got enough bandwidth to handle the load.

Comment Re: Militant Slashdot (Score 4, Insightful) 295

The reason you don't understand this is because you are ignorant (perhaps willingly so) of how the people that want to ban weapons have thought out their plan. These people know that banning handguns, or most any weapon really, is the goal but they also know that banning handguns is difficult politically.

To understand this best we must go back in time by nearly a century. The National Firearms Act of 1934 placed a prohibitively high tax on a number of weapons, among them were machine guns, firearm report suppressors ("silencers"), "destructive devices" (grenades, landmines, large bore ammunition, etc.), the curious catch-all "any other weapon", and the also curious "short barreled" rifles and shotguns.

Let's talk about that "short barrel" category. The 1934 NFA originally had the intent to ban handguns and to prevent people from making handgun analogs from the not banned rifles and shotguns they made sure that people would not be allowed to shorten the barrels on these "long guns". Because of resistance from a number of powerful groups the ban on handguns went away but the "short barrel" designation remained. This law created the distinction among "handguns", "long guns", and "short barrel" arms where none existed before.

Forty years later the group Handgun Control Incorporated was created, with the (obvious) intent to ban handguns. Again this was met with resistance politically, few people in politics wanted to be associated with a group of that name. In 1981 James Brady was seriously injured in the assassination attempt on Ronald Reagan. HCI found themselves a new "mascot" and renamed themselves to the Brady Campaign. James Brady was shot with a .22 caliber revolver, which seems like a perfect mascot for an organization that wanted to ban handguns.

At about 1989 HCI renamed themselves Brady Campaign but still kept their original intent on banning handguns. The difference now is that they didn't wear this intent on their sleeves. It was now more politically acceptable to be an advocate for those injured by "gun violence" in general, leaving out that the ultimate goal is still banning handguns if not all firearms.

As the decades passed the banning of handguns became even less politically viable. People wanted personal defense weapons and a handgun makes a reasonable weapon for this task. The people today that call for "reasonable" gun control can draw a direct lineage to those people that wanted to ban handguns nearly a century ago. Given the age of many of these politicians and public figures I have to wonder if these aren't the same people that signed the 1934 National Firearms Act into law.

These bans on "assault weapons", magazine limitations, and background checks are all part of the boiling the frog, oiling up that slippery slope, or what have you that will lead us to banning handguns. These people have tried for over a century now to ban handguns but the majority of the people won't have it. They are still working on sharpening the point of the wedge between people and their personal defense arms. They think that by creating the idea that limits on some arms should bring us down the path to limits on all arms. That once we create the idea that the government should be able to dictate with what tools we are permitted to defend ourselves that at some future point in time the government would be able to dictate that the people cannot have any tools of self defense.

This has been going on for a long time in the USA, the best that they've been able to do is place some rather trivial limits on the people's ability to arm themselves. What I find interesting about these advancements in 3D printing is that it makes all those laws irrelevant. They can make it illegal to manufacture these weapons but the people that feel the government should not be able to dictate how the people may arm themselves will find these bans exceedingly difficult to enforce.

This is a question I've asked myself many times, is a law really a law if the government lacks the willingness or ability to enforce it? Congress can pass a law dictating the color of the sky but that does not make the sky any color other than blue. Look at the federal marijuana prohibition and the number of states that have openly defied the ban. Marijuana is not prohibited any more because the government lacks the will and/or ability to enforce it. If people can make machine guns in their basement with nothing more than a $1000 printer, melted down Coke bottles and beer cans, and some files they downloaded from the internet then does a ban on machine guns really exist any more?

Remember folks, people in the USA used to be able to mail order a Thompson sub-machine gun from the Sears catalog less than 100 years ago. Civilization didn't end then. If this ability is restored by technology, not legislation, in 2034 then I expect nothing real to come of it other than people regaining a freedom lost 100 years ago.

Comment Re:Old News (Score 1) 51

Considering that these are high dollar custom built cars I suspect that putting in an over sized starter motor would be both a minimal additional cost and a selling point.

Also, I recall my high school physics teacher stating something similar about a car he owned. He said he'd use the starter to move a "dead" car to the side of the road.

Another data point is a former co-worker told me how he built a go-cart that was propelled by a starter motor from an old truck. He use a set of automotive batteries and had to put two solenoids in parallel to handle the current. The problem was not with the motor getting too hot but the contacts on the solenoid would. Using two kept them from getting too hot.

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