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Kinetic motion

Rigid bones are needed for kinetic motion, support of internal organs, and muscle strength. The bones that compose the human thigh are pound for pound stronger than steel. Nature meets these needs by separating the skeleton into several bones and bone systems, creating joints where the bones intersect. [Pg.185]

The general relativistic Hohenberg-Kohn-Sham formalism, outlined above, contains the spin degrees of freedom in a complete form. Consequently, the spin and kinetic motion effects are not separable. Indeed, they are contained in the external potential term as one can see if such term is written using the orbital current... [Pg.140]

The molecular interpretation of this result is as follows above the glass temperature T0 the molecular segments are in vigorous motion and change their positions frequently. Hence, the average nuclear spin interaction is reduced to a minimum. This causes a narrow absorption line. As the kinetic motion of the molecules is decreased by cooling, the frequency of position changes is reduced, and... [Pg.59]

KINETIC THEORY. A theory (proved by experiment) that explains the phenomena of heal and pressure as due to the kinetic motion and elastic collisions of atoms and molecules. The phenomena include gas and vapor pressure, evaporation, and diffusion of fluids. [Pg.902]

In addition, we assume, for the systems of interest here, that the electronic motion is fast relative to the kinetic motion of the nuclei and that the total wave functions can be separated into a product form, with one term depending on the electronic motion and parametric in the nuclear coordinates and a second term describing the nuclear motion in terms of adiabatic potential hypersurfaces. This separation, based on the relative mass and velocity of an electron as compared with the nucleus mass and velocity, is known as the Born-Oppenheimer approximation. [Pg.229]

Finally in the diffusa- section 5 the pressure is recovered from the kinetic motion of the gas through some kind of shock wave - the fact which is well known in gas dynamics. Certainly the pressure recovers not up to the initial inlet value. The pressure losses (typically 20 - 30% at present) depend on the desired temperature in the working section 3 (as desired temperature is lower the gas movement is faster and pressure recovering is more difficult). This section acts like a compressor in TET. [Pg.154]

Mathematically, this separation of the kinetic motions of the electrons and nuclei amounts to approximating the total wavefunction P (x, R) by a simple product of electronic and nuclear wavefunctions... [Pg.2]

How does a gas exert pressure In a sense, it cannot exert measurable pressure in the same way that a solid or liquid can. The pressure of a gas is determined by the kinetic motion of its component molecules. Suppose hundreds of billions of gas molecules are in random motion, striking the entire inner surface of their container. Each collision exerts a force on the container s inner surface. [Pg.425]

Eq. 3.39 shows that each component of kinetic motion contributes equal by to the total kinetic energy and that the kinetic energy for each degree of freedom is 1/2 kT per molecule or 1/2 RT per mole. [Pg.116]

There are certain essential differences between solid state reactions and reactions involving gaseous or liquid phases. In the latter case, the kinetic motion of the reactant molecules ensures that they are available to one another for reaction under conditions which can be defined by statistical laws. Solid state reactions occur between apparently regular crystal lattices, in which the kinetic motion is very restricted and depends on the presence of lattice defects. Interaction can only occur at points of contact between the reacting phases and is therefore dependent on particle size and particle size distribution. The factors which govern the rate of a solid state reaction are (/) the rate of the boundary phase processes which lead to the consumption of the original lattices, and (ii) the rate of particle transfer through the product layer. [Pg.254]

Although thermodynamically the diffusion pump is highly inefficient, it can achieve a speed as high as 40% to 45% of the ideal pump, which pumps out all molecules streaming to the mouth of the pump by random kinetic motion. The difficulties with breakdown of the pumping fluid noted in connection with the vapor ejector, also apply to the diffusion pump. Silicone oils which are less susceptible to chemical breakdown are now gaining a wider use as diffusion pumping fluids. [Pg.141]

Philips et al. (18) reported that in mixed monolayers of dioleoylleci-thin—distearoyllecithin, the area/molecule showed expansion from the additivity rule because the unsaturated fatty acid chains increased the kinetic motion of saturated chains. However, in contrast to the studies here on Ci6 + Ci8 alcohols, they found no expansion in the mixed mono-layers of dipalmitoyllecithin-distearoyllecithin. [Pg.171]

In Williamson s vivid conception, this process happens continuously and randomly, promoted by the constant kinetic motion of the molecular participants and pushed to completion by the stability of the resulting products, ether and water, and their removal from the site of reaction. He illustrated his mental vision of this molecular dance by means of formula tableaux that made clear the various displacements of the ethyl radicals. His paper thus contains what is probably the first competent and empirically plausible proposal for an important reaction mechanism, a viewpoint that was founded upon the "broader basis of atomic motion."... [Pg.53]

The kinetic motion of molecules may cause them to change their spatial distribution through successive random movements. This is the process of diffusion, which is a transport property. Other transport properties include viscosity, electrical conductivity, and thermal conductivity. While diffusion is concerned with the transport of matter, these are associated with the transport of momentum, electrical charge, and heat energy, respectively. Transport is driven in each case by a gradient in the respective property. Thus, the diffusion rate of species A is given by Pick s law. [Pg.255]

In analytical chemistry, NMR is a technique that enables us to study the shape and structure of molecules. In particular, it reveals the different chemical environments of the NMR-active nuclei preseut in a molecule, from which we can ascertain the structure of the molecule. NMR provides informatiou on the spatial orientation of atoms in a molecule. If we already know what types of compounds are present, NMR can provide a means of determining how much of each is in the mixture. It is thus a method for both qualitative and quantitative analysis, particularly of organic compounds. In addition, NMR is used to study chemical equilibria, reaction kinetics, motion of molecules, aud intermolecular interactions. [Pg.114]


See other pages where Kinetic motion is mentioned: [Pg.411]    [Pg.315]    [Pg.293]    [Pg.654]    [Pg.28]    [Pg.13]    [Pg.386]    [Pg.196]    [Pg.266]    [Pg.160]    [Pg.380]    [Pg.39]    [Pg.113]    [Pg.239]    [Pg.153]    [Pg.479]    [Pg.9]    [Pg.266]    [Pg.411]    [Pg.252]    [Pg.315]    [Pg.103]    [Pg.260]    [Pg.411]    [Pg.315]    [Pg.388]    [Pg.261]    [Pg.38]    [Pg.78]    [Pg.256]    [Pg.257]    [Pg.444]   
See also in sourсe #XX -- [ Pg.52 ]

See also in sourсe #XX -- [ Pg.52 ]




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