Seriously? Did you even read the article? It isn't saying that exercising isn't good for you, it is that extreme sedentary living is very, very BAD for you.
is like birthday cake without catsup and mustard.
Seriously, it's time for Fortran to die. I'm a Chemical Engineer and end up having to use Fortran for programming custom routines inside commercial chemical process modeling software. I was just talking to one of our support reps the other day, and he deigned to pull out the "C++ code doesn't run any faster than well-written Fortran code" argument. The problem isn't about speed or code execution efficiency anymore, it's about 1) ease and efficiency of programming/debugging, and 2) availability of people who are competent programming in the language. Fortran is an epic fail on both fronts; it had its place, now it's time to cede it to better tools. Python would fill its place nicely for many uses when relatively small programs are required (NumPy is a great numerical method's module for arrays and such.) More powerful languages like C++ are well-suited for larger projects.
It should be telling that the authors of the venerable book Numerical Recipes have decided to no longer update the Fortran version of the book and only update the C++ version.
The "gasoline fuel cells" convert the hydrocarbon (usually diesel or a biofuel) to hydrogen and carbon dioxide using a well-known industrial process called steam reforming. There are actually a couple of similar reactions as well, most of which also require water and heat.
What allows such fuel cells to have reduced CO2 emissions compared to internal combustion engines (ICEs) is the fact that fuel cells are much more efficient. A well-tuned fuel cell system can be 40% efficient (electrical energy out / chemical energy in); that is reduced somewhat by the electric motor, but electric motors are actually quite efficient. An ICE is lucky to be 20% efficient. So, for the same power you emit considerably less CO2 using a fuel cell system than an ICE. It would still be better not to emit ANY CO2, but we aren't quite there yet.
You forgot that you have to SUPPLY energy to run the Fischer-Tropsch reaction necessary to convert these reactants to hydrocarbons. And you need to convert the CO2 to CO first of all, requiring more energy.
Nuclear power is actually a great way to form H2. In fact, if you use a VHTR (Very High Temperature Reactor), you can form hydrogen directly from the thermal lysis of water. The mechanical portion of the higher temperature nuclear reactor is more efficient thermodynamically, and the additional H2 generation makes the overall process even more efficient.
As someone who works in the fuel cell industry (an who works with hydrogen on a daily basis), I can unequivocally say I'd rather use hydrogen than gasoline as a fuel.
Your scenario of the fuel tank "blowing" presumably refers to a mechanical rupture. Either fuel would quickly escape from the tank and potentially form an explosive mixture with air. Because gasoline vapor is more dense than air, the explosive air/gasoline mixture tends to hug the ground and stay near the source of the vapor (i.e. the liquid gasoline remaining in the tank or on the ground). A spark would ignite the explosive mixture and create heat which would quickly vaporize (and ignite) the rest of the gasoline.
Hydrogen is the least dense of all elements, so a potentially explosive mixture rises away from the source (ruptured tank). Also, hydrogen disperses exceptionally rapidly in air (almost 600% more quickly than gasoline vapor), which allows an explosive mixture to quickly disperse and dilute below the lower explosive limit of 4% in air.
Finally, the energy density of hydrogen is much less than that of gasoline. That's a great advantage from a safety standpoint. Fuel cells are extremely efficient (much more so than combustion engines); that's how they are able to overcome this energy-density "deficiency" with respect to hydrocarbon fuels.
That completely depends on what you end up doing professionally. I'm a chemical engineer and I use my HP-48S day in and day out. Most of my mechanical engineering friends also have HP-48s sitting on their desks and they use them often as well.
I also use MATLAB extensively, as well as Mathcad. I use Excel when I have too. Each tool has its niche, and it depends on what you do (in general) and what you are doing as to which tool best suits the task. A programmer probably won't use a calculator very often, but if you are an engineer or scientist, you certainly will.
A superconducting grid may also be the missing incremental step towards increased hydrogen use. The superconducting transmission lines would have to be cooled. If liquid hydrogen were used as a coolant, then it would provide an alternative (but less efficient) form of energy storage to saved fossil fuels. The producers would provide a mix of hydrogen and electricity and inject them into the transimission line. On the receiving end, the hydrogen would be gasified and converted into electricity at a rate sufficient to maintain cooling in the transmission line.
Ummmm...hydrogen has to be kept below -253 C to be maintained as a liquid. Even under pressure, hydrogen is usually stored as a gas (as opposed to the propane in your BBQ). Nitrogen only has to be kept below a relatively balmy -196 C, which is why most current semiconductor research, and all 'practical' semiconductor technology, uses liquid nitrogen as the coolant.
I don't see transmission lines ever being cooled with liquid hydrogen. The heat losses over the distances we're talking about would be so great, you would use all of your available electricity to run the refrigeration units necessary just to keep the hydrogen cool.
Palladium's affinity for hydrogen is actually used in many steam reformers today, but not as a storage medium (the metal hydrides others mentioned do a better job at this). It is used as a separator.
A palladium/silver alloy lets pure H2 to diffuse through, leaving behind the CO2, CO, water, and other chemicals which are also products of steam reforming. This gets you better than 99.9975% pure hydrogen for the fuel cell. This is important because some chemicals, like carbon monoxide (CO), can really mess up fuel cells (at least the PEM fuel cells used in most concept cars and in systems which could be adapted for home use).
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Seriously? Did you even read the article? It isn't saying that exercising isn't good for you, it is that extreme sedentary living is very, very BAD for you.
is like birthday cake without catsup and mustard.
Seriously, it's time for Fortran to die. I'm a Chemical Engineer and end up having to use Fortran for programming custom routines inside commercial chemical process modeling software. I was just talking to one of our support reps the other day, and he deigned to pull out the "C++ code doesn't run any faster than well-written Fortran code" argument. The problem isn't about speed or code execution efficiency anymore, it's about 1) ease and efficiency of programming/debugging, and 2) availability of people who are competent programming in the language. Fortran is an epic fail on both fronts; it had its place, now it's time to cede it to better tools. Python would fill its place nicely for many uses when relatively small programs are required (NumPy is a great numerical method's module for arrays and such.) More powerful languages like C++ are well-suited for larger projects. It should be telling that the authors of the venerable book Numerical Recipes have decided to no longer update the Fortran version of the book and only update the C++ version.
The "gasoline fuel cells" convert the hydrocarbon (usually diesel or a biofuel) to hydrogen and carbon dioxide using a well-known industrial process called steam reforming. There are actually a couple of similar reactions as well, most of which also require water and heat.
What allows such fuel cells to have reduced CO2 emissions compared to internal combustion engines (ICEs) is the fact that fuel cells are much more efficient. A well-tuned fuel cell system can be 40% efficient (electrical energy out / chemical energy in); that is reduced somewhat by the electric motor, but electric motors are actually quite efficient. An ICE is lucky to be 20% efficient. So, for the same power you emit considerably less CO2 using a fuel cell system than an ICE. It would still be better not to emit ANY CO2, but we aren't quite there yet.
You forgot that you have to SUPPLY energy to run the Fischer-Tropsch reaction necessary to convert these reactants to hydrocarbons. And you need to convert the CO2 to CO first of all, requiring more energy. Nuclear power is actually a great way to form H2. In fact, if you use a VHTR (Very High Temperature Reactor), you can form hydrogen directly from the thermal lysis of water. The mechanical portion of the higher temperature nuclear reactor is more efficient thermodynamically, and the additional H2 generation makes the overall process even more efficient.
...www.zengineersco.com. They do board design and prototyping, and can help you get set up with a manufacturer.
As someone who works in the fuel cell industry (an who works with hydrogen on a daily basis), I can unequivocally say I'd rather use hydrogen than gasoline as a fuel.
Your scenario of the fuel tank "blowing" presumably refers to a mechanical rupture. Either fuel would quickly escape from the tank and potentially form an explosive mixture with air. Because gasoline vapor is more dense than air, the explosive air/gasoline mixture tends to hug the ground and stay near the source of the vapor (i.e. the liquid gasoline remaining in the tank or on the ground). A spark would ignite the explosive mixture and create heat which would quickly vaporize (and ignite) the rest of the gasoline.
Hydrogen is the least dense of all elements, so a potentially explosive mixture rises away from the source (ruptured tank). Also, hydrogen disperses exceptionally rapidly in air (almost 600% more quickly than gasoline vapor), which allows an explosive mixture to quickly disperse and dilute below the lower explosive limit of 4% in air.
Finally, the energy density of hydrogen is much less than that of gasoline. That's a great advantage from a safety standpoint. Fuel cells are extremely efficient (much more so than combustion engines); that's how they are able to overcome this energy-density "deficiency" with respect to hydrocarbon fuels.
That completely depends on what you end up doing professionally. I'm a chemical engineer and I use my HP-48S day in and day out. Most of my mechanical engineering friends also have HP-48s sitting on their desks and they use them often as well. I also use MATLAB extensively, as well as Mathcad. I use Excel when I have too. Each tool has its niche, and it depends on what you do (in general) and what you are doing as to which tool best suits the task. A programmer probably won't use a calculator very often, but if you are an engineer or scientist, you certainly will.
...and they've sold what, two whole copies of Vista Enterprise so far?
Ummmm...hydrogen has to be kept below -253 C to be maintained as a liquid. Even under pressure, hydrogen is usually stored as a gas (as opposed to the propane in your BBQ). Nitrogen only has to be kept below a relatively balmy -196 C, which is why most current semiconductor research, and all 'practical' semiconductor technology, uses liquid nitrogen as the coolant.
I don't see transmission lines ever being cooled with liquid hydrogen. The heat losses over the distances we're talking about would be so great, you would use all of your available electricity to run the refrigeration units necessary just to keep the hydrogen cool.
Palladium's affinity for hydrogen is actually used in many steam reformers today, but not as a storage medium (the metal hydrides others mentioned do a better job at this). It is used as a separator.
A palladium/silver alloy lets pure H2 to diffuse through, leaving behind the CO2, CO, water, and other chemicals which are also products of steam reforming. This gets you better than 99.9975% pure hydrogen for the fuel cell. This is important because some chemicals, like carbon monoxide (CO), can really mess up fuel cells (at least the PEM fuel cells used in most concept cars and in systems which could be adapted for home use).