What is the difference between UNIQUAC and UNIFAC models?
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Theories of Solutions : Excess functions (and consequently activity coefficients)\ncan be obtained from equations of state. However, this approach has limited\npractical applicability.\n· Lattice Models :\nLiquid is considered to be a quasicrystalline state with molecules arranged in a\nregular array. Mixing two different liquid to obtain a solution results in the\nentropy of mixing (as lattice structure is altered) and enthalpy of mixing (due to\nintermolecular forces). The potential energy of the system is obtained by pairwise\naddition of all molecular pairs considering only the nearest neighbors. An\nexpression for Helmholtz energy can be derived in terms of the interchange\nenergy (w) which arises when a molecule of one component in the lattice is\nreplaced by the molecule of the second component. The interchange energy is\ndependent upon the difference in the potential energies of pairs 1-2, 1-1 and 2-2\n(for a binary mixture of 1 and 2). For a regular solution the excess Gibbs energy is\nequal to excess Helmholtz energy, leading to a method for calculation of activity\ncoefficients. The interchange energy can be calculated from potential functions\nand molecular properties, primarily for mixtures of nonpolar molecules similar in\nsize. This approach is not very useful for mixtures having additional complexities.\n· Non-random Mixtures:\nA solution is essentially non-random in nature as in most cases intermolecular\nforces for different compounds are not identical. So in a binary mixture of 1 and\n2, molecules of 1 either prefer 2 or 1 as immediate neighbors. The solution has\ncertain order to it resulting in sE < 0. A quasichemical theory for such solutions\ncan be developed by writing an equilibrium constant expression for the formation\nof complex 1–2 from molecules of 1 and 2. The equilibrium constant is related to\nthe interchange energy w, leading to expressions for excess Helmholtz energy,\nexcess entropy and excess Gibbs energy.\n· Two-Liquid Theory:\nSince the solutions are essentially non-random, they can be thought of as\ncomprised of 2 (or more) hypothetical fluids depending upon the nature of\ninteraction between the solution components. The thermodynamic properties of\nthe solution are then mole fraction weighted averages of the properties of the\nhypothetical fluids. Area fractions and volume fractions can be defined for each\nhypothetical fluid, and expressions developed for the excess properties of the\nsolution. The UNIQUAC equation, developed on the basis of two- liquid theory is\nquite successful, however, it may over-correct for non-randomness of the\nsolution.\n· Group Contribution Methods\nActivity coefficients can be calculated for various mixtures by considering\nindividual molecules to be comprised of different functional groups. The number\nof distinct functional groups (methyl, methylene, hydroxyl, etc.) is relatively\nsmall compared to the number of distinct compounds. The interaction between\nvarious compounds is obtained by contributions of the functional group\ninteraction for the compounds. ASOG (analytical solution of groups) and\nUNIFAC (universal functional activity coefficient) are two group contribution\nmethods that are quite useful. Group contribution methods are very rapid,\nhowever, they may not necessarily be accurate. The results of the group\ncontribution methods need to be compared with experimental data for validation.\n· Chemical Theory of Non- ideality of Liquid Solutions:\nThe non- ideality of the solutions is due to formation of new species by the\nreactions of the components. These reactions may be associations of a single\ncomponent (dimmer, trimer, polymer formation) or solvation (interactions of two\nor more components, e.g. complexation). These species are at chemical\nequilibrium with each other and form ideal solutions. Therefore, the behavior of\nthe solution can be described if the “true” composition of the solution is\ndetermined. If z1 and z2 are
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i have used both at the same\ntums work right away\npepcid takes a  little longer\nbut they both work for me
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Both are essentially the same. Get the one that gives you the most for the least money.
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There are multiple units usable.  Try pascals, psi, torr, atm
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there can't be. "uni-" means one (imagine having different UNIforms for a team). there IS, however, the theory of multiverses, that you might be interested in searching for and having a read about.
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I trust Gateway a little more, but basically it would boil down to price versus options. eMachines is usually a little less expensive for the same performance, while Gateway has been known for slightly higher quality.
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http://www.xe.com/ucc/
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Here is a very thorough and point-by-point comparison of these two products:\n\nhttp://financialsoft.about.com/od/reviewsfinancesoftware/a/MDel06vsQDel06.htm
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This weblink will explain the differance between the 2\nhttp://www.erg.abdn.ac.uk/users/gorry/eg2069/async.html
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It would really be greatly helpful if you would post links so that we don't have to go looking for each one individually, but I can basically tell you that there is little difference between most of them, they all use the 7900GS, so any differences would be minimal.
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An authentic is exactly like the pros wear but a replica you cant really tell the difference.  You could trick someone if they didnt really look close.  The price is much more expensive for the authentic but you cant tell the difference between the 2 jeresys.  They are jeresys either way and the replica would save you tons of money.
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They don't say what they are because you are suppose to get a copy of B31.9 and follow its requirements. \n\nB31.9 can change from time to time and this way the specification is always current. If the specification spelled out B31.9 and then quoted the requirements and they had changed in the mean time there would be a conflict.\n\nI have written many specifications for piping and this is the only way to be sure B31.9 or other industry standards are met.
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CISC machines generally have a relatively large and complicated instruction set,several different instruction formats and lengths and addressing modes,while in RISC ,the number of machine instructions,instruction formats and addressing modes is relatively small.\n\nCISC implementations are Pentium and VAX,and those of RISC are UltraSPARC architecture,PowerPC and CrayT3E architecture.
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They are both financial intermediaries.  They both trade risks for a premium.  They are both regulated financial institutions.  They both have highly leveraged balance sheets.
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The difference between the two are their connector interfaces and cache sizes. The first one connects via FireWire (IEEE 1394) and has  a 2MB cache. The second drive connects via USB and has an 8MB cache.\n\nBoth drive will be close in performance. The FireWire drive doesn't have as large of a cache, however, Firewire has a faster sustained transfer rate. The USB has a slower sustained transfer rate, however, it has an 8MB cache and will be compatible with more computers. (many computers lack Firewire, while most have usb).
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a ditisbution transformer is much larger . but they both do the same job .they either step up or step down current.
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http://www.speedytoys.com/shop/item.asp?itemid=309\n\nit depends on what you are looking for in the gun.\nfor the money, probably the utg master.  the fps is better than the more expensive HFC, its not as powerful as the UHC swat, but is considerably cheaper. heres my analysis.\n\nUTG: 315-325 fps. $99\nUHC: 500 fps. $140\nHFC:280-300 fps. $105