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Natural constants

The constant 607 is a combination of natural constants, including the Faraday constant it is slightly temperature-dependent and the value 607 is for 25 °C. The IlkoviC equation is important because it accounts quantitatively for the many factors which influence the diffusion current in particular, the linear dependence of the diffusion current upon n and C. Thus, with all the other factors remaining constant, the diffusion current is directly proportional to the concentration of the electro-active material — this is of great importance in quantitative polarographic analysis. [Pg.597]

Max Planck (1858-1947 Nobel Prize for physics 1918) at first did not have the atom in his sights. He was more interested in thermodynamics, and especially in the laws of radiation. In 1900 he surprised the Physical Society of Berlin — and later the whole world — with an experimentally based realization that changed the world view. In contrast to time and space, energy is guantized. Thus it does not form a continuum, but is essentially "grainy". The smallest unit is the Planck constant, a fundamental natural constant. [Pg.24]

The unchanging validity and applicability of the laws of physics and of the fundamental natural constants across a period of four billion years The applicability of the theory of evolution to molecular systems... [Pg.316]

In fact, the value of the constant c in Equation (1.1) comprises several natural constants, including the acceleration due gravity g and the density p of the mercury. [Pg.6]

If the isomeric transition is taking place under conditions where the molecules cannot interact with one another or with the walls of the vessel in which they are contained other than in sueh a way as to transfer energy or momentum, the activation energy Qa and Qb will be determined entirely by the internal characteristics of the molecule and will be what might be termed natural constants of the system, analogous to the heat of formation. Thus under these conditions the reaction rates for the isomeric transitions will be fixed by the internal constitution of the molecules. At a given temperature the reaction rate can be changed... [Pg.11]

Both constants o and o are expressions of and can be calculated from the natural constants k, h, and c, which were discussed earlier. Equation 17.5, which relates the energy flux to the absolute temperature, is known as the Stefan-Boltzmann equation. The coefficient o is known as the Stefan-Boltzmann constant. The average photon energy can be calculated from... [Pg.305]

Furthermore, one has to bear in mind that relating energy with temperature implies the consideration of the Boltzmann s constant, k. However, this natural constant will play a role in a physical problem only if the molecular nature of matter is involved, otherwise it is irrelevant. [Pg.79]

In dealing with Boussinesq s problem, Lord Rayleigh used the amount of heat H (measuring unit calorie) as one of the then used base dimensions. Only since the introduction of SI (Systeme International d Unites) it was required to make no distinction between heat and mechanical energy, because both were considered to be equal. In order to comply with this requirement, the Joule equivalent of heat J [M L2 T2 H-1] had to be introduced as a natural constant in the relevance list. If we proceed from the assumption of an inviscid , ideal liquid, no mechanical heat can be converted into heat. In this case, J is irrelevant. [Pg.79]

The proportionality can be expressed as op(ji = /Jg opJ, where / (called the magneton, in usual units J/T) is a collection of natural constants, and g is a 3x3 dimensionless real matrix in three-space. Some authors refer to g as a second-rank tensor, but in fact (strictly speaking) it is not.8 For a detailed discussion, consult Section 9 below. We shall not use the term tensor, unless this is unavoidable. [Pg.3]

The paper that reported these results ended with the recognition that there was a problem Whether the failure of theory and experiment to agree is because of some unknown factor in the theory of the hydrogen atom or simply an error in the estimate of one of the natural constants, such as [the fine structure constant], only further experiment can decide. This was the result that Rabi conveyed to the physicists at Shelter Island. Rabi s reputation as an experimentalist brought credibility to the measured results and issued a challenge to the theorists. As with the Lamb shift, it was quantum electrodynamics that was brought to bear on... [Pg.165]

It could be mentioned that in this work, a new improved nuclear factor was obtained. This may be the very first time MD simulations have contributed in the determination of a natural constant. Absolute shielding constants are important quantities, besides in NMR spectroscopy, as the experimental values for theoreticians calculating shielding constants quantum mechanically. An interesting theoretical application of including the short-time-scale thermal fluctuations from MD trajectories to quantum chemical calculations of chemical shielding constants is reported by Chesnut and Rusiloski [78]. and by Woolf et al. [79]. [Pg.313]

Here, e, m, A, and c are well-known natural constants, pj = -iftV, is the linear momentum operator, and r, is the position operator of electron /. For... [Pg.145]

We have already seen, in the case of money, how value, having become independent as such - or the general form of wealth - is capable of no other motion than a quantitative one to increase itself. It is according to its concept the quintessence of all use values but, since it is always only a definite amount of money (here, capital), its quantitative limit is in contradiction with its qtialily. It is therefore inherent in its nature constantly to drive beyond its own barrier. .. Already for that reason, value which insists on itself as value preserves itself through increase and it preserves itself precisely only by constantly driving beyond its quantitative barrier, which contradicts its character as form, its inner generality. ... [Pg.39]

The two radiation constants cx and are made up of fundamental natural constants, from the velocity of light c0 in a vacuum, the Planck constant h and the Boltzmann constant k. With the best values for these quantities, according to [5.8],... [Pg.529]

In conclusion, the following numerical values of natural constants may be tabulated, expressed in every case on the C.G.S. system —... [Pg.245]

The second base number may not be as familiar to some readers, but it is actually encountered much more frequendy in PK models as well as many other areas of mathematics. This base number is a natural constant called e, where e has an approximate value of 2.7182818, but the actual number of digits goes on forever without repeating. The logarithm with base e is called the natural logarithm, and often is written as In, giving... [Pg.203]

Of course further study of the first 100 trillion digits of n would have to be done to determine what is really going on. I think this problem receives far too much attention. I suggest instead that the NSF fund the exploration of the other natural constant, e. [Pg.67]

A traditional source of glass making sand was at the mouth of the Belus River. This was the town of Ptolemais, now called Acre. " Josephus and Pliny mention it, noting that the sand here would form crystals. These were crystals of quartz and chalcedony in the presence of calcium from decayed seashells. Josephus writes that many ships called to load sand for glassmaking and that nature constantly replenished it. Josephus described a very unusual property of these crystals if they overflowed the basin, they reverted to ordinary sand. [Pg.343]

It is obvious that the cross-correlated relaxation rate depends on natural constants, material constants, distances and that need to be known, as well as the desired intervector angle 0nh,ch and the correlation time that can be determined experimentally. Fig. 21 shows a schematic representation of C,N double-quantum-coherence multiplets depending on the inter-vectorial angle 0nh,ch- If the angle is 0 or 180°, the outer multiplet lines are broadened whereas the inner lines are narrowed. For 90°, the situation is reversed. For the magic angle 0n h=54° no effect is observed since (3 COS 0NH CH - 1) = 0. [Pg.59]

In this case, N is the particle number, r is the elementary amount of substance that we already used in Sect. 1.4, and is the Boltzmann constant (a natural constant just as R and t). Accordingly, we obtain for pressure according to the (modified) gas law ... [Pg.278]

In addition to the ordinary dimensions of quantity, concentration, volume, time, and temperature, the kinetic expressions in enz5mie kinetics may contain various natural constants, and it is always useful to keep in mind the definitions, magnitudes, and the dimensions of principal natural constants. Table 2 lists the major natural constants that are of practical use in enz5mie kinetics. [Pg.29]

Table Useful natural constants in enzyme kinetics... Table Useful natural constants in enzyme kinetics...
We see Faraday always willing to follow experiment, even if it led him towards quantification, and towards and away again from matter theory as his ideas developed and matured. Faraday repudiated the supremacy of mathematics in the exploration of nature, but he recognised that in the divinely-ordained economy of nature, constant proportions must apply (80). In his discovery of the first law of electro-chemistry, mathematics had a clear, but circumscribed, role. [Pg.46]


See other pages where Natural constants is mentioned: [Pg.7]    [Pg.227]    [Pg.137]    [Pg.120]    [Pg.304]    [Pg.212]    [Pg.19]    [Pg.24]    [Pg.372]    [Pg.145]    [Pg.365]    [Pg.323]    [Pg.148]    [Pg.106]    [Pg.10]    [Pg.344]    [Pg.184]    [Pg.674]    [Pg.1137]    [Pg.81]    [Pg.41]    [Pg.525]    [Pg.4985]   
See also in sourсe #XX -- [ Pg.29 ]




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