Wikipedia:Reference desk/Archives/Science/2015 February 11

= February 11 =

Cross Reaction Drugs Petri Dish pictures
I have searched & searched the www & cannot find one petri dish picture of a drug cross reaction (i.e., Aspirin, etc.c)& only found 2 that are "reaction" it should like the one drug is reach across the petri dish to the other.

Thank you,

Cynthia Privitera, RN, BSN, MSN, APRN, FNP-BC Nursing Faculty Nevada Career Institute — Preceding unsigned comment added by 65.223.25.38 (talk) 01:05, 11 February 2015 (UTC)


 * Could you explain a bit more what you mean? Maybe I should see it but I didn't.  You make me think of Ouchterlony double immunodiffusion but I'm pretty sure that's not what you want.  (maybe someone else understands though) Wnt (talk) 01:31, 11 February 2015 (UTC)


 * Do you mean where one drug kills some of the bacteria in a circle around it, and another kills some of the bacteria around it, but at the intersection almost all the bacteria are dead ? StuRat (talk) 01:41, 11 February 2015 (UTC)


 * We have an article about the agar diffusion test, which is the type of test you describe, albeit for a single compound to test. It sounds like (similar to StuRat's idea) you mean to have disks of different individual agents, and see if there are unusual effects where their diffusion overlaps (enhanced or reduced effectiveness compared to the simple additive effects of the two agents individually). I found some references to "double disk synergy" tests, eventually landing at and, each of which have some pictures. DMacks (talk) 06:01, 11 February 2015 (UTC)

Dirt blower
Is there something similar to a snow blower, but grinds up dirt and rocks instead and accelerates them in a powerful collimated jet? 69.121.131.137 (talk) 02:14, 11 February 2015 (UTC)


 * There's a leaf-blower and a garden hose, as well as a sand-blaster. If your goal is to ping the neighbors' house, see bb-gun.  Google is your friend. μηδείς (talk) 02:22, 11 February 2015 (UTC)


 * A wood chipper would work for dirt, but big rocks would be a problem. For those you'd need diamond or corundum blades.  And getting the materiel into the wood chipper would be problematic.  If you don't just want to drop the items in, you'd then need a device to dig it up and put it in the chipper for you. StuRat (talk) 02:40, 11 February 2015 (UTC)


 * Did you check Crusher? A snow blower is dangerous enough when blasting out the snow. I suspect that a rock blower would be somewhat worse. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 00:44, 12 February 2015 (UTC)

How can those Flicker 3 Wheel Scooter move uphill?
Or move at all at a flat surface. I wonder how skate boards can do it too, BTW. See [] if you don't know what I mean.--Noopolo (talk) 02:22, 11 February 2015 (UTC)


 * Trikke works pretty much as skating does. Jim.henderson (talk) 02:31, 11 February 2015 (UTC)


 * Or skiing or skateboarding. In all such cases, you could build up enough momentum to get over small hills, but long, steep hills would indeed be a problem.  The easiest way in those cases would be to get off and walk/push. StuRat (talk) 02:36, 11 February 2015 (UTC)


 * I'm pretty sure the OP is referring to climbing a long (but probably shallow) hill using a trikke, not just relying on momentum to get over a small hump. Our article suggests it's possible, as does a simple search. You don't have to get off, the whole point of the trikke appears to be that you can propel it without getting off, the same way you can with a bike (although the way you do it is quite different). It's perhaps worth remembering there's noting that unique about hills. If you can propel yourself forward on a e.g. flat surface from a standing start (or gain speed if not a standing start) without relying on gravity or the wind or something, then you just need to be able to generate enough force to counteract the effect of gravity (and the wind) going up a hill. Nil Einne (talk) 15:19, 11 February 2015 (UTC)


 * Just like with a one-speed bike, there is a certain steepness of hills where you can't go up anymore, and have to get off and walk. There is also a point before that, where it becomes easier to do so.  Similarly, there's a reason you don't often see people skiing up steep hills. StuRat (talk) 15:26, 11 February 2015 (UTC)
 * But the point is you're generating the force to climb a hill. Talking about building up momentum to get over a small hills is confusing since it sounds like you're referring to simply relying gravity from long down travel which is clearly not what's being referred to. Whether with a bike, or with a trikke, in both cases you can successfullly climb a long (albeit probably shallow unless you're very good) hill if you have the stamina without needing to get off. Nil Einne (talk) 15:32, 11 February 2015 (UTC)


 * No, not enough kinetic energy at the bottom of the hill to carry you to the top. That's clear from the video I shot for the Trikke article, when I chanced upon it while bicycling.  At the end of each zig, the legs push so the vector of momentum will point to the opposite side, to carry the rider through the zag.  Not as efficient as a roller skater climbing a hill, but similar in principle and effect.  Workable, though I prefer the benefits of the more mechanically complex pedaling action. Jim.henderson (talk) 15:29, 11 February 2015 (UTC)

Power electronic
What is power electronic? — Preceding unsigned comment added by YogR9923 (talk • contribs) 09:05, 11 February 2015 (UTC)


 * Likely this is Power electronics the use of electronics for the control and conversion of electric power. (I have done a course in this if you have more specific questions). Graeme Bartlett (talk) 10:26, 11 February 2015 (UTC)


 * Or it could just be a redundant way to refer to any electronics, particularly if they want to make them sound more impressive: "The all new XL9000 features power electronics to get any job done quickly !". StuRat (talk) 15:29, 11 February 2015 (UTC)


 * power electronics is also a genre of highly disturbing electronic music. One of the most popular of these groups is called Whitehouse.99.61.19.139 (talk) 02:00, 12 February 2015 (UTC)

Is the Law of conservation of energy being the absolute law of physics?
1) Is nuclear physics being the physics of ideal situation – the physics of ideal model, that is, whether is all cases of nuclear physics being the ideal cases of physics?

2} Why work (energy) of electrons of nucleus of an atom is not being observed in other sections of physics, if the Law of conservation of energy is always being the universal law of physics (nature), that is, if the Law of conservation of energy is always being observed in physics (nature)?--83.237.223.123 (talk) 09:40, 11 February 2015 (UTC)
 * 1 - nuclear physics is not so useful for explaining many other physical phenomena, eg acoustics optics. However I think you need to ask question 1 again as I donot understand. Graeme Bartlett (talk) 10:24, 11 February 2015 (UTC)
 * 2 - The energy of electrons in an atom results in chemical energy. The law of conservation of energy applies to this too, and changes to these electrons may result in heat, or light energy being produced, eg a burning candle. Graeme Bartlett (talk) 10:24, 11 February 2015 (UTC)


 * Much thanks! If the same physical phenomena could be physical-mathematically described by different ways, whether are these laws of physics and also mathematics identical (equal) to each other, if for example the work (energy) of electrons atom's nucleus is unstable in different sections of physics?--83.237.192.148 (talk) 11:05, 11 February 2015 (UTC)


 * Did the ideal case of physics being identical (equal) to particular case of physics, that is be, did the physical-mathematical values in physics are proportional to each other?--85.141.236.139 (talk) 12:34, 11 February 2015 (UTC)

We do not know. The latest articles seem to say the Big Bang was impossible as a result of quantum mechanics - which means a lot of theorists are working overtime. For all reasonable purposes for anyone else, conservation of mass and energy seems to work fine. Collect (talk) 15:19, 11 February 2015 (UTC)
 * The quantum Big Bang is impossible due to the fact that quantum physics is a special particular case of nuclear physics!--83.237.215.225 (talk) 17:48, 11 February 2015 (UTC)


 * Since the physical-mathematical values are dependent on each other, so this gives claim that physical-mathematical values are proportional to each other, is it correct?--83.237.215.225 (talk) 17:48, 11 February 2015 (UTC)

Did the natural magnetism of the planet Earth as a physical outside working body - the energy, always doing work on conservation of the balance of energy in the nature of the planet Earth, thus achieving absolute compliance with the Law of conservation of energy in all applications in the physical and chemical models?--83.237.215.225 (talk) 18:35, 11 February 2015 (UTC)
 * From last to first, third, the natural magnetism of the Earth, see Earth's magnetic field, which does respect conservation of mass-energy, and has complex causes due to motion and electricity in the Earth. Any effects that the magnetic field has on objects in its magnetic field will affect the Earth's rotational kinetic energy and rotational angular momentum; because the Earth is so much larger than any other objects affected by its magnetic field, the observable effect will be minimal.  (This is also true of the effect of the Earth's gravitational field on small orbiting objects).  Robert McClenon (talk) 18:50, 11 February 2015 (UTC)
 * Second, it is true that the Big Bang appears to violate the law of mass-energy, and, as previous posters note, this is a matter of theoretical attention. However, it is not clear what set of quantum equations apply "before" or "at" the Big Bang, so that it is not obvious how to quantify mass-energy "before" or "at" the Big Bang.  Robert McClenon (talk) 18:50, 11 February 2015 (UTC)
 * First, it is the best scientific thinking that the law of conservation of mass-energy is absolute. (That is not the same as the classical law of conservation of energy or the classical law of conservation of mass, because relativity provides that energy and mass are interchangeable, or two ways of stating the same quantity.)  Robert McClenon (talk) 18:50, 11 February 2015 (UTC)
 * Please review these answers and see if your question has been answered, or if you meant to ask some other question. Robert McClenon (talk) 18:50, 11 February 2015 (UTC)


 * Sincerely thank you, unfortunately I did not know that there is be a kinematics of mass, as because always believed that in nature there is only be the kinematics of accelerations, so that I did not consider that the physical-mathematical units (values) of mass any way being proportional to physical-mathematical units (values) of work (energy), so I think that applied mathematics is always be a weak point of theoretical physics.--83.237.201.24 (talk) 08:45, 12 February 2015 (UTC)
 * Believed, that the Law of conservation of energy is always retains the gravity of mass, but not the same physical mass.--83.237.201.24 (talk) 09:00, 12 February 2015 (UTC)
 * We could assume that some of the mathematical and physical units (values) did not had a values, that is being, these mathematical and physical units (values) are always being a dysfunction of mathematics.--85.141.232.219 (talk) 10:41, 12 February 2015 (UTC)
 * It could be assumed that the value of identities (equals) in mathematics and physics always detects the presence of an absolute, but not relative possibility of solving mathematical and physical problems (tasks) as well as the identity (equally) in mathematics always detects the presence of capabilities of the mathematical solving, thus proving the identity (equally) of the mathematical proves the possibility of being the some mathematics and physics absolute units (values)!--85.141.237.211 (talk) 13:23, 12 February 2015 (UTC)
 * As a result, there is be a absolute identity (equally) between each other of the some physical-mathematical units (values), which constantly absolutely expressing the physical-mathematical and physical-chemical values of the potential of energy in nature, these it be the accelerations, pulses, work, forces, pressure and other absolute.--83.237.197.203 (talk) 15:41, 12 February 2015 (UTC)
 * Believe, that in physics the resting state of any body is always being a particular case of motion (displacement) of bodies, so that in physics the potential energy and identity (equally) to her a physical-mathematical units (values) are always being a particular case of the kinetics.--83.237.216.207 (talk) 18:53, 12 February 2015 (UTC)
 * In physics, the identity (equality) of accelerations to each other, is always determining all cases of balance of the Law of conservation of energy in nature.--83.237.222.238 (talk) 08:56, 13 February 2015 (UTC)
 * Hi. To find answers to this thread's titled question see conservation of mass-energy, but I'm afraid that the article is not likely to be of much help to you because of your abstract beliefs, although devoid of the necessary mathematics here, have led you to believe that energy conservation is absolute. That is fine of an answer too. -Modocc (talk) 18:32, 13 February 2015 (UTC)
 * The ideal case of the Law of conservation of energy had being a work performing or a work performed, thus in the nature of the planet Earth there is a balance of the Law of conservation of energy (works).--83.237.203.165 (talk) 07:08, 15 February 2015 (UTC)

Unit of mass
Can mole (unit) be in some situations a unit for mass? This seems to follow from the description of mole as the amount of substance whose mass in grams is numerically equal to the relative molecular mass of that substance.--92.81.43.185 (talk) 10:54, 11 February 2015 (UTC)


 * Sure, if you specify the substance, and specify that it's pure, then saying you have one mole of it also determines how much mass the sample has, provided that we know the mean molecular mass. But just because molar units can be used to calculate mass, doesn't mean that it is a unit of mass. A gram is a gram, no matter if it's a gram of water or iron. But a mole of iron and a mole of water have very different masses. From the article: "The number of molecules in a mole (known as Avogadro's constant) is defined such that the mass of one mole of a substance, expressed in grams, is exactly equal to the substance's mean molecular mass". Moles are often used as units when describing chemical reactions, because the number of molecules is important in determining what happens. If you actually want to tell someone the mass of something, just use a mass unit :) SemanticMantis (talk) 15:13, 11 February 2015 (UTC)


 * By the same argument cubic centimeters (a measure of volume) can also be a measure of mass in some situations. That might be valid in some formalistic sense, but it's a bad way of thinking and is best avoided.  Moles are dimensionless. Looie496 (talk) 15:45, 11 February 2015 (UTC)


 * A mole can be said to have mass no more than a million can be said to have mass. A set of a million atoms of Carbon-12 has some specific mass that is equal to some non-round number, a set of a mole of atoms of Carbon-12 has a specific mass that is equal to 12 grams.  The roundness of the result in the second case doesn't change the fact that both 'a million' and 'a mole' are just numbers. --Noren (talk) 20:24, 11 February 2015 (UTC)

Sanitary whole house humidifier ?
I'm asking about the type that attaches to the furnace, where hot air is blown through a filter that's kept soaked with water, and that humid air is then distributed through vents to the house. The problem is that all sorts of microbes, contained in that air, are blown through that warm, moist filter, allowing the nasties to grow on it, then send their spores throughout the house.

So, what's the cure ? Any type of chemical disinfectant seems to be out, because then that disinfectant vapor would spread throughout the house. Could a UV light work ? I doubt if the light could get everywhere inside the filter, but it might help a bit. I suppose we could just abandon the whole-house humidifier and boil water and use individual room humidifiers, but that's a major inconvenience (and risk, in terms of the pot boiling dry). StuRat (talk) 16:51, 11 February 2015 (UTC)


 * The big problem is Legionnaires' disease. Protocols (that in the UK are legally binding) have be drawn up: The control of legionella bacteria in water systems--Aspro (talk) 17:32, 11 February 2015 (UTC)


 * Do you already have such a humidifier? Humidity is never a problem in NYC, since steam heat is near-universal.  But my parents have a house-humidifier and my dad cleans it and consults the manual.  If you know the company, they should have a FAQ website and an 800 number.


 * PS, I can very highly recommend the http://www.walmart.com/ip/Vicks-Warm-Steam-Vaporizer which is only $14.95. It runs by boiling the water with an electrode placed in the top of the tank, and stops running when enough water has vaporized so that the electrodes are no longer submerged.  No spraying of droplets, no risk of infection. μηδείς (talk) 17:34, 11 February 2015 (UTC)


 * Vicks sells this model so cheap because they expect you to add menthol or whatever they sell separately, which of course you need not do. Also, you have to prime the water the first time and each time you empty it with two pinches of salt, to allow the water to conduct electricity.  (I don't empty it often.  I just bring a new pitcher of water, which is easier to carry and fill than the tank.)  And because it is an electric current, you'll eventually get a build-up of precipitate of whatever metals are in your tap water.


 * Those are room humidifiers, not whole house humidifiers, which means buying multiple units and refilling each daily, and occasionally cleaning scale off each. I want a "set it and forget it" system.  And yes, we already have a whole house humidifier, and I want to know how to keep disgusting things from growing on it. StuRat (talk) 20:04, 11 February 2015 (UTC)


 * Yes,, they do need refilling daily if the house stays dry, but unless you have your windows open during cold weather, they work quite well, and three of them is strategic areas will cover most homes where cost is a consideration. Going to a nearby sink with a pitcher is no worse than having to set a thermostat and pay a specialist or do the cleaning grunt work as if you were a real man, born before the internet.


 * I spend most weekends and holidays at my parents', and have the largest room in the house, which is an attic guestroom with only the floor and one wall contiguous with the house, as opposed to the outside cold. It has central heating, but if I leave the vents open it becomes like a convection roaster.  So I close the vents and put on the variation of the Vicks humidifier I linked to above I bought about 10 years ago for $9.95.  The humidifier both heats the room and humidifies it, and only needs to run every other day t keep the room cozy.


 * One in the bedroom, one in the kitchen, and one in the laundry room will serve most homes. Otherwise, the option is either a new, heavy-duty humidifier to go in the furnace room that produces steam (i.e., sanitized water gas) and is drawn through the house, or call your current manufacturer. μηδείς (talk) 21:11, 11 February 2015 (UTC)


 * How many units you need would depend on the house size and insulation, outside dew point, and how often the doors are opened. StuRat (talk) 23:41, 11 February 2015 (UTC)


 * Well, of course,, I understand the variables. I would recommend you buy one (it's only $14.95 when not on sale!) and try it out.  They really are wonderful humidifiers.  My parents live at the SJ highpoint (well, close to, google the west end of the AC Expressway) and there's no Great Lake to lessen their drought.  In fact, I asked my dad just last week why he doesn't leave his wooden door open and his glass storm door shut on sunny days (a front doorway, with a due south view) and he said it was due to the loss of humidity. He and my mother complain endlessly about how bad the house humidifier is for all the labor Dad puts into it. μηδείς (talk) 04:31, 12 February 2015 (UTC)


 * Here's an article from the EPA: (bottom line: follow the manufacturer's directions)  —71.20.250.51 (talk) 20:36, 11 February 2015 (UTC)


 * Wow, they suggest changing the water daily and scrubbing every 3 days, for portable humidifiers. That's a heck of a lot of work.  I see there's room out there for a better design. StuRat (talk) 15:52, 12 February 2015 (UTC)


 * A low maintenance and safe option is a "flow-through" humidifier tho costly to buy and get installed. Here is a site explaining it tho you could search for more info about 2 other main systems out there if you wish. here they explain the systems available. If you don't want to invest in expensive systems like those, you can place a pan or water soaked pad in the hot air vent's path but you'll still have to replace and/or clean (disinfect) the tray and/or pad at least once a month. You should have at least 2 sets of pads so you can clean one (using bleach or another disinfectant detergent) and install it dry when needed.TMCk (talk) 23:53, 12 February 2015 (UTC)


 * That's the type we have now. The tap water flowing through provides minerals, the furnace provides heat, the air blown through provides the mold spores, and the filter provides a nice scaffolding for the to grow on.  Put them all together and you have a paradise for mold. StuRat (talk) 06:14, 13 February 2015 (UTC)

Schuko plugs with smaller pins
I used to own two or three electrical appliances which had a Schuko-like plug with smaller pins (I bet they were 4.0 mmm instead of 4.8 mm). All the other features were the same as usual (guiding notches, lateral grounding and so on). Could they have been Russian GOST plugs?--Carnby (talk) 18:51, 11 February 2015 (UTC)
 * See AC power plugs and sockets and GOST 7396. The GOST standards do define a version of the CEE 7/17 plug (which is a hybrid between the French CEE 7/5 and the true CEE 7/4 Schuko) with 4mm rather than 4.8mm pins, although it doesn't (apparently) have a separate type number in the GOST system. Tevildo (talk) 19:26, 11 February 2015 (UTC)

How to power a cell-phone through a USB connection instead of the battery.
I have a cell-phone with a battery that's almost dead (30 min. running time at best). I use this cell-phone as a 3G modem, but it cannot be operated without a battery although it is connected to a USB port. The battery has 4 contact points, and I wonder whether I could connect a USB cable to two of these contact points and power it through another USB port. — Preceding unsigned comment added by Fend 83 (talk • contribs) 19:49, 11 February 2015 (UTC)


 * What happens when you use the phone with the battery installed and with the USB plugged in at the same time ? (Hopefully, it will charge the battery as quickly as it discharges, so it will never go dead.) StuRat (talk) 19:54, 11 February 2015 (UTC)


 * Not really. It goes dead but in takes longer than 30'. It has to be recharged then with the original charger. Apparently USB charging is weaker than that. Anyway, I imagine that this battery will get weaker and weaker and then stop working all completely in the future, so I need to find an alternative to it. — Preceding unsigned comment added by Fend 83 (talk • contribs) 20:02, 11 February 2015 (UTC)


 * No, USB is 5 volts, cell phone batteries are usually ~4 V. So at some point between the charger and the battery, there's a DC-DC converter to reduce the voltage. Do you have it plugged into a computer or an AC-USB adapter? The maximum current on a computer USB port is <1 A, but AC adapters can deliver 2 - 5. Most phones can handle a higher current, so they'll charge faster with a AC adapter than in a computer. Mr.Z-man 20:14, 11 February 2015 (UTC)


 * Mine is 3.7 V 750 mA. Can't you just use a resistor to do this drop of voltage?--Fend 83 (talk) 21:29, 11 February 2015 (UTC)


 * Good advice. Also, sooner or later you need to replace that old battery.  There should be a model number on the battery.  If you do a Google search on that, I'll bet you will find replacement batteries for sale online, even if the phone model is discontinued.  One warning, though, is that they tend to sell batteries as "new" which are many years old, but presumably have never been used.  I got such a battery, and it was a definite improvement over the old battery, but still not as impressive as a genuinely new battery would be. StuRat (talk) 20:28, 11 February 2015 (UTC)


 * The idea was to use the phone without battery as a cheap 3G modem. Otherwise, I could save the battery price and buy a pen-drive modem.--Fend 83 (talk) 21:29, 11 February 2015 (UTC)


 * It might be cheaper than you think, if there's a surplus of batteries for a now discontinued phone model. (This is payback for making every cell phone battery unique.) StuRat (talk) 23:44, 11 February 2015 (UTC)


 * should call the phone and computer csr svc hotlines and ask about this, rather than return to us saying his computer has shorted out and his phone's on fire, along with the curtains. μηδείς (talk) 20:52, 11 February 2015 (UTC)


 * The problem with the idea of connecting the USB to the terminals of the battery compartment is that batteries are a lot more than dumb AAA dry cells. Most of them have all sorts of internal components that do things like measuring charge and internal temperatures.  When you get rid of all of those thing, the phone's main computer is going to be upset.   So this might require more complexity than you imagine to get it to work.   The other thing that the battery does is to allow the phone to temporarily use more power than the USB can provide....and then pay for that later by using less power and having the excess recharge the battery.   By evening out the peaks and troughs of usage, the phone can gradually take energy saving measures when it sees that the battery is getting low - which is a lot easer than predicting the instantaneous demand a millisecond into the future and minimizing the current draw to avoid overloading the USB and dying.
 * Sadly, your phone needs it's battery...and you're probably doomed without it. SteveBaker (talk) 21:42, 11 February 2015 (UTC)

I don't quite follow your setup. Is the USB connection necessary for your modem setup, or is it used only for power? If it's used only for power you have some possibilities for getting more current. Short Brigade Harvester Boris (talk) 03:11, 12 February 2015 (UTC)


 * Yes, I can get some power, but the cell-phone consumes more than can be recharged through an USB during use. After that I have to use the charged and stop using the cell-phone as 3G modem.Fend 83 (talk) 11:03, 12 February 2015 (UTC)


 * Apologies, my question was unclear. Is the USB cable necessary for transmitting data through your modem connection, or is it used only for power? Short Brigade Harvester Boris (talk) 13:19, 12 February 2015 (UTC)


 * Yes, it gets data through the cable. Although a blue tooth connection could be established too.Fend 83 (talk) 18:52, 12 February 2015 (UTC)


 * According to the WP Disclaimer, we do not give professional advice that may end up in death, severe injure, or catastrophic property damage. μηδείς (talk) 04:22, 12 February 2015 (UTC)


 * Yes, please don't make connections that bypass the safety circuitry. Would a powered USB hub provide the necessary current?  I would guess that 2000ma (10 watts) should be sufficient for your phone, but you can get more powerful ones if your phone is particularly power-hungry.   D b f i r s   13:26, 12 February 2015 (UTC)


 * Semi-educated opinion here: As mentioned above, a powered USB hub might do the trick. I'd try a USB 3 hub since it should supply more amps per port. Bypassing the battery by connecting a power supply directly should be only done by someone with knowledge as you'd need not only make the right connection but also having the right and steady voltage to prevent the phone going into charging mode. Otherwise the unit can malfunction like overheating and even explode in a worst case scenario. Don't think you want to wear protective gear and having a fire extinguisher ready to use while surfing ;) TMCk (talk) 23:05, 12 February 2015 (UTC)

Just to share personal experience with people saying their batteries do not hold a charge long enough, I tell them to turn their phone off and on (reboot, restart etc) before or after charging. Every time the battery last longer. I suspect phones with poor design have processes that start and never stop and do nothing but use up charge. Richard-of-Earth (talk) 19:50, 13 February 2015 (UTC)


 * Yes, it's surprising how many processes can be running in the background. GPS and WiFi also use up battery power.  You can download a process monitor that can check and terminate unwanted processes ( but then, it's another process to run!)    D b f i r s   08:45, 14 February 2015 (UTC)


 * I feel I should point out that there's a fair chance a powered USB hub won't work. The way that phones determine whether to draw more current are varied, but they often require some sort of signal on the data pins. There are some recent standards, but these seem to be poorly implemented. (Some phones may refuse to draw more power when there's a data connection point blank.) If we're talking Android here, you may want to consider a battery monitor app before bothering to even try this. Remember that not all phones will even draw more power. If your phone draws the same with its own charger as it does from the USB port, then it's very likely there's simply no way to make it charge faster. You could get a new battery. But consider that you could probably get a 3G for USD20 or something, it may not be worth it if you're only using the phone as a 3G modem. Also, if your talking Android, iOS or I'm guessing Windows Phone, you shouldn't need a process monitor to turn off GPS, WiFi etc. In fact, I would hope you turned them off a long time ago. In fact, if it is a modern smartphone and you only use it for the 3G, I would hope you not only did this, but uninstalled everything you could. (As the phones may come with bundles apps which can't be uninstalled, a process monitor may still be useful. Then again, if you have such a phone and if you look at the power usage history which you probably should, and it's nearly all going to the 3G connection, then this isn't likely to help much.) Nil Einne (talk) 16:52, 14 February 2015 (UTC)


 * This is why I asked whether the USB cord was used for data transmission. If the user can connect with Bluetooth, (s)he can then use a power-only USB cord. As Nil mentions the USB data pins are used to tell the device how much power to draw. Shorting the data pins tells the device that it's plugged into a charger rather than a computer. Obviously, you can't short the data pins if they are being used to communicate data.
 * You can buy charge-only cables from your favorite vendor. If you're handy with a soldering iron you can gin up one yourself: short pins 2 and 3 (the two inside pins on the connector) or slit the cable and short the green and white wires. Short Brigade Harvester Boris (talk) 17:03, 14 February 2015 (UTC)

Research papers
When writing a research paper do you need to go into the theory when justifying methodology? For example, if you added a catalyst to a reacting solution, you would justify the addition of the catalyst but is it necessary to go into the chemistry of it if the addition of the catalyst is simply to speed up the process and not part of your investigation. 194.66.246.4 (talk) 19:51, 11 February 2015 (UTC)


 * It might be nice to either add it as an addendum, or else provide a link to where it is explained. StuRat (talk) 19:56, 11 February 2015 (UTC)


 * I'd say it would depend on how common the practice is. If it's something that everyone else working in the field does or something that people have been doing for decades, a citation to an earlier paper describing it would be sufficient. If it's something that only your lab does or is rather new, you may want to add some additional explanation for people unfamiliar with it. How important it is to the actual findings would also be relevant - was it for some minor intermediate step in a long process, or was it the most important part? If you went into the theoretical detail about every part of your methodology, that section would be longer than the rest of your paper. Mr.Z-man 20:07, 11 February 2015 (UTC)
 * It was a minor part of a very long experimental procedure. Is it also common practice to put safety precautions taken in the methodology? 194.66.246.4 (talk) 20:28, 11 February 2015 (UTC)
 * Safety is not normally seen in papers unless the risk is extreme or unusual. eg 20 mg of the product will explode. (so make less than that). Safety will be part of the methodology, so the same applies above, document it if it is unusual or affects your results. Graeme Bartlett (talk) 21:30, 11 February 2015 (UTC)
 * Check with your journal or editor for guidelines. Content varies by publication.  For example, Science (journal) "now requests" that, in general, authors place the bulk of their description of materials and methods online as supplementary materials, providing only as much methods description in the print manuscript as is necessary to follow the logic of the text."  Nimur (talk) 02:36, 12 February 2015 (UTC)
 * Yes, this is what counts. Whether for publication or just a student paper, the advising faculty member should also be consulted. SemanticMantis (talk) 14:04, 12 February 2015 (UTC)