Space connected

In molecular distillation, the permanent gas pressure is so low (less than 0 001 mm. of mercury) that it has very little influence upon the speed of the distillation. The distillation velocity at such low pressures is determined by the speed at which the vapour from the liquid being distilled can flow through the enclosed space connecting the still and condenser under the driving force of its own saturation pressure. If the distance from the surface of the evaporating liquid to the condenser is less than (or of the order of) the mean free path of a molecule of distillate vapour in the residual gas at the same density and pressure, most of the molecules which leave the surface will not return. The mean free path of air at various pressures is as follows —... 

Serial leaks this is the teak at the end of several spaces connected in series , e.g. a leak in the oil-filled section of the oil pan in a rotary vane pump... 

The most definitive proof of p-sheet structure requires the determination of the three-dimensional solution structure of the peptide. For the calculation of such structures one requires the accurate determination of coupling constants by DQF-COSY experiments which give backbone dihedral restraints and through-space connectivities (ROESY or NOESY experiments) which give rise to distance restraints. A combination of these restraints allows the calculation of the three-dimensional structure of the peptide using restrained molecular dynamics simulations. Utilizing this methodology, the three-dimensional structures of a number of cyclic peptides have been solved.[411... 

However, all standard NMR parameters are of short-ranged nature chemical shifts are typically affected by the first and second sphere of atoms surrounding the nucleus and usually provide only qualitative measures 3/-couplings are limited to dihedral angles via three covalent bonds and through space connectivities via NOE can only be found up to 5 A in favourable cases. As soon as the chain of short-range information is interrupted by NMR-inactive nuclei or a flexible linker, distant parts of a molecule cannot be correlated and the structure determination is bound to fail. 

One solution to the problem of limited accuracy is to evaluate the kinetic energy matrix elements not in position but in momentum space connected via Fourier transformation [10,45]. In momentum space, the kinetic energy operator is diagonal and the associated matrix elements can be calculated by simple multiplication, followed by a back transformation to position space. 

However, if we view electromagnetic radiation as a collection of particles (photons), then the intensity is simply proportional to the density of photons in a region of space. Connecting the wave and particle views of the electromagnetic field suggests that the probability of finding a photon is given by the square of the amplitude of the electric field. 

This type of heteronuclear 3D experiment is called NOESY-HMQC. (In Figure 6-37, there are two H dimensions and one N dimension.) Most 3D experiments use high-sensitivity methods and displays that are particularly effective for large molecules. Thus, COSY is not often used, but TOCSY-HMQC is a useful method for separating H- H coupling connectivities into a C or " N dimension. The homonuclear 3D experiment NOESY-TOCSY (all three dimensions are H) separates through-space connectivities from... 

For a lattice of atoms in d-dimensional space connected to nearest neighbors by bonds of similar strength, d = D = d. In this case, we have the simple dispersion relation, co k, where k is the wave number. 

Evidently, the first step in any NMR study of carbohydrates involves assigning proton and carbon resonances. This can be done on the basis of scalar and through space connectivities, using 2D/3D homo- and hetero-nuclear correlation experiments.1,4-6 10... 

Traditionally, homonuclear 2D double quantum filtered correlation spectroscopy (DQF-COSY) and total correlated spectroscopy (TOCSY) spectra are valuable in the identification of resonances of individual monosaccharide units. In the presence of small couplings, through space connectivities detected by NOESY/ROESY (nuclear Overhauser effect spectroscopy/ rotational nuclear Overhauser effect spectroscopy) experiments are also useful in completing the resonance assignment. When the H NMR spectra of complex oligosaccharides are too crowded to fully elucidate the structure by homonuclear correlation methods, it is efficient to use 2D heteronuclear correlation methods, such as heteronuclear single quantum correlation... 

Mason, G. (1982). The effect of pore space connectivity on the hysteresis of capillary condensation in adsorption-desorption isotherms. J. Colloid Interface Sci., 88, 36-46. 

Contaminants released indoors in one space served by a recirculating system could be redistributed rapidly to all spaces connected to the same system. The distribution of contaminants released in one space to other spaces is much more limited in a once-through system. However, pressure differences created by wind, stack effect, and HVAC fan operation can cause flows between what, in theory, are isolated spaces. 

Cable theory Representation of a cylindrical fiber as two parallel rows of resistors (one each for the intracellular and extracellular spaces) connected in a ladder network by a parallel combination of resistors and capacitors (the cell membrane). 

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