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Everything posted by Sensei
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Not quite. You're describing just the most abundant isotope of Oxygen: Oxygen-16. There are two more stable Oxygen isotopes: Oxygen-17 and Oxygen-18. http://en.wikipedia.org/wiki/Isotopes_of_oxygen This is true only for the first 20 elements. Ca-40 is the last one with even quantity of protons and neutrons. Sc-42 is unstable. Ti-44 is unstable. V-46 is unstable. Little difference of isotope property, might mean huge difference for living organisms. The most of multicellular organisms are dying after drinking heavy water for too long (with Deuterium isotope instead of Hydrogen).
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Cloud chamber is typically used (for 100 years) for visualizing decay of radioactive elements. They decay via couple methods: Beta decay minus (emitting electron & antineutrino) http://en.wikipedia.org/wiki/Beta_decay Beta decay plus (emitting positron & neutrino) http://en.wikipedia.org/wiki/Positron_emission Double beta decay minus (two electrons at the same time) Double beta decay plus (two positrons at the same time) Proton emission http://en.wikipedia.org/wiki/Proton_emission Neutron emission http://en.wikipedia.org/wiki/Neutron_emission Alpha decay http://en.wikipedia.org/wiki/Alpha_decay And few more rare decay modes. That's done for hundred years.. It's impractical for Nitrogen & Oxygen. They are approximately 28 and 32 more heavy than proton. Thus far more energy is needed to accelerate them. See instruction at website. It's extremely easy.
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Do you even know what is cron?! Your reply has no sense at all.. http://en.wikipedia.org/wiki/Cron
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Everything has its use. But above technique is too slow for more advanced projects. In real database you want as less as possible slow disk accesses. Data frequently requested by db clients should be cached in computer memory. Such web portals have separate directory for each user or so (otherwise they would end up with millions files in one folder - very hard to list by scandir()). But they don't keep all info there. Just f.e. photos, files user uploaded etc.
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CSV, which is "database for poor", we also have similar problems. At the beginning we just know file name and path. We have to go through all rows doing f.e. fgets() (which ends reading at EOL), counting them, at the same time we can store offsets at which each row is in file, at the same time we can store offsets at which each column is in row. And we have index of rows, and index of columns within rows. Then to read cell at col,row we just have to do something like offset=index[row][col] and read buffer with size=index[row][col+1]-index[row][col] Real database must have such index file already done, to not have to parse entire db each time db is opened.
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More memory consumption. Type of field attached to every cell. So something like at least 1-4 bytes more per cell *). Which means more I/O data has to be read/written to/from disk. *) variable length string needs 4 bytes for length with 4 GB limit, or 8 bytes for length on 64 bit computer. Or you need to figure out how to have null terminated cell.. Might be really problematic. Take for example db with fixed field size: to access row y you just need to calc offset= y*sizeof( row ) and you're done and read/writing whole row with sizeof(row). Extremely simple. If every row has different length then you need to store these lengths somewhere..
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Bluetooth is pretty slow. http://en.wikipedia.org/wiki/Bluetooth When it's +HS it's not really Bluebooth transfer rate but IEEE 802.11 wifi..
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We can see electrons and alpha particles (Helium-4 nucleus), and other highly accelerated ions, in Cloud Chamber device. When they're passing through chamber, they ionize medium (mixture of alcohol with air) and leave visible trace. You can see it on YouTube videos: Or you can even build your own particle detector for 50 usd or so, following instructions given here http://www.ultimate-theory.com/en/2014/6/8/how-to-build-cloud-chamber-particle-detector
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Wow. It's essential. There are also 3D versions of it, where magnets are not on needle and rotating in 2D, but "flying in air" connected to grid by elastic material. Brute force method of making compass array device is buying/making hundred compasses like here: Example 3D versions (68 usd) (not the best one because needles are still rotating in 2D plane) It's quite big - needles have 1.5 cm length. It has 200 and 400 needles-compasses (according to website description).
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Just a side note. Somebody who wants to play with magnetisms should get compass array device (or even couple - you could make experiments with wires, passing current through them, working motors, and other electrical devices). It costs $28.5. Highly recommend it. It's from this shop http://www.eduvis.pl/oferta/fizyka-pomoce-dydaktyczne/elektrycznosc-i-magnetyzm/zestaw-nr-84-przyrzad-do-demonstracji-linii-pola-magnetycznego-detail
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All negative Clicks must be made Public !
Sensei replied to Commander's topic in Suggestions, Comments and Support
Where did EdEarl (or anyone other than you) say this? I'd like to know the context. http://www.scienceforums.net/topic/59897-reputation-versus-time/?p=754909 -
All negative Clicks must be made Public !
Sensei replied to Commander's topic in Suggestions, Comments and Support
For "layman with new great revolutionary theory" typical route to get negatives is such: - introduction of (not finished) theory, which is rather hypothesis (without math and any calculations which would agree with world) - we are telling where are errors - layman is ignoring what we just said, and is angry that we don't admire his work (after all he spend on it "few years" so they claim).. - discussion about everything except theory.. Starting from lacks of knowledge of layman. It more looks like "preaching" to get "followers", than discussion about science & how Universe works. Not in science. Opinions are meaningless in science. Make your own lab experiment, make photos, or record on video, show calculations, that will predict result of experiment in future. If you will show us that you're doing real science, people will appreciate it with positives. -
1) Hydrogen is not noble gas 2) Hydrogen is not mentioned in article I linked.
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That depends on which noble gases you have in mind. On Earth there are known to be existing compounds made of heavy noble gases such as Krypton and Xenon. http://en.wikipedia.org/wiki/Noble_gas_compound IMHO it has more to do with quantum physics than chemistry..
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So far, so good. That would be the worst est implementation of binary search I heard of. Making NEW ARRAY? No. That would be very slow implementation. You should pass original array pointer, and indexes - to the beginning and to the end, or start index, and quantity (at the beginning start=0,quantity = list.length). void binary_search( data *list, int start, int count, data x ) { data value = list[ start + count / 2 ]; // take element at middle if( x > value ) binary_search( list, start + count / 2, count / 2, x ); else if( x < value ) binary_search( list, start, count / 2, x ); else { /* found */ } } (I skipped actual finding code, it's just to give you picture of passing indexes, without creating new array!)
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Coin example is not really random indeed. It just appears to human random, because of lack of data. But what with example from #5 post? Show how you control direction of reflected photon. So they're not randomly scattered.
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There are experiments in which electrons are colliding with positrons. Can create heavy mesons at relativistic velocities. In other experiments protons are colliding with antiprotons with relativistic velocities. At pretty small velocities (it's called "pion production threshold" if you want to search google): [math]p^+ + p^+ \rightarrow p^+ + p^+ + \pi^0[/math] neutral pion produced [math]p^+ + p^+ \rightarrow p^+ + n^0 + \pi^+[/math] neutron and charged pion produced
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1) gravitational waves 2) black hole evaporation, Hawking radiation 3) many related to black holes You have list here http://en.wikipedia.org/wiki/Category:Astronomical_hypotheses
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(Outernet) Some progress on MAMP(Major/Minor Data Protocol)
Sensei replied to Unity+'s topic in Computer Science
I have no idea what are you talking about. You can't get source PHP script from any 3rd party website. Only output generated by it. You can't even be sure whether PHP was used to generate it. index.php and [file name].php extensions are not obligatory. I have many files f.e. image.png which are actually PHP scripts generating PNG as output (have to generate HTTP response proper headers).. Extension is meaningless. -
(Outernet) Some progress on MAMP(Major/Minor Data Protocol)
Sensei replied to Unity+'s topic in Computer Science
I didn't think about jQuery at all - it's completely different level of dynamically created websites - on browser side. Until downloading page, decoding it, interpreting, JavaScript is not executed - that's where jQuery will generate something. I was thinking about generating on HTTP server side, PHP and JSP and similar technologies. Their output is normal HTML. But each time, each request, slightly different. So your web content caching will fail with them. "Then, when a device connects to any of these connective devices, the device will be able to connect and request a website page and data required to fill it out. When the request is made, the device first will check if the file exists on it. If not, it will refer to the other devices it is connected to through a recursive method. The device will make requests to both of its devices it is connected to see if they have the files. If so, the devices will send the files to that device making the request, then that device will send the data to the original device that requested the information." -
(Outernet) Some progress on MAMP(Major/Minor Data Protocol)
Sensei replied to Unity+'s topic in Computer Science
Currently majority of websites are made dynamically. Each time you go to website, different content is returned. And they're using parameters to tell browser "page is new". If you will backup file on disk ignoring parameter, it'll be most likely obsolete version. Also device which has the smallest ping is not necessarily the one that has the smallest ping to website you're looking for. It just means that device is near you and/or is very fast and/or is not busy. Anyone can configure Apache HTTP server to do bottom part of what you want - and work as proxy server. -
Tor https://www.torproject.org/ Download and install app browser, that's modified Mozilla/Firefox. When you go to URL it's sending packet to Tor server (each time randomly picked one), instead of where you wanted to go. Then that server is sending real requests to website, downloading it, and then sending to you in encrypted form.. ISP won't know where you go, what you watched, and won't filter, block it.
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Please help with calculating limiting reagent?
Sensei replied to PistolSlap's topic in Organic Chemistry
Apparently you don't understand how Universe works. You have f.e. 2 Hydrogens and 1 Oxygen on left side of equation, then they join/react, and there is created H2O as product. Quantity of atoms must match! Otherwise it would be like creating stuff that was not there! How could be negative quantity of some atoms?! He used some broken software "i got the negative numbers by inputting the formula into a equation balancer.".. Its programmer didn't do proper job at idiot-proofness and allowed negative numbers to be used.. -
Plug heating element to power source, put to water with mass m, and initial temperature T0 Electricity measure by ampere meter and volt meter, with stopwatch, You will have U, I, and t Energy from heating element will be E=U*I*t=P*t and it'll be used to increase energy of water. 1 calorie is 4.1855 J/g*K And you have equation: m*4.1855*(T1-T0)=U*I*t T1 - final temperature of water after t seconds. One of the simplest thermodynamics experiments..
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Not C but K rather.