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Core complications

Proteins often have the same high-affinity isotherms as do synthetic polymers and are also slow to equilibrate, due to many contacts with the surface. Proteins, however, have the additional complication that they can partially or completely unfold at the solid-liquid interface to expose their hydrophobic core units to a hydrophobic surface... [Pg.404]

There are complicating issues in defmmg pseudopotentials, e.g. the pseudopotential in equation Al.3.78 is state dependent, orbitally dependent and the energy and spatial separations between valence and core electrons are sometimes not transparent. These are not insunnoimtable issues. The state dependence is usually weak and can be ignored. The orbital dependence requires different potentials for different angular momentum components. This can be incorporated via non-local operators. The distinction between valence and core states can be addressed by incorporating the core level in question as part of the valence shell. For... [Pg.112]

Patent databases are therefore integrated databases because facts, text, tables, graphics, and structures are combined. In patents that include chemical aspects (mostly synthesis or processing), the chemical compounds are often represented by Markush structures (see Chapter 2, Section 2.7.1). These generic structures cover many compound families in a very compact maimer. A Markush structure has a core structure diagram with specific atoms and with variable parts (R-groups), which are defined in a text caption. The retrieval of chemical compounds from Markush structures is a complicated task that is not yet solved completely satisfactorily. [Pg.269]

Basis sets can be constructed using an optimisation procedure in which the coefficients and the exponents are varied to give the lowest atomic energies. Some complications can arise when this approach is applied to larger basis sets. For example, in an atomic calculation the diffuse functions can move towards the nucleus, especially if the core region is described... [Pg.92]

When the relative pressure falls to pj/p", the second group of pores loses its capillary condensate, but in addition the film on the walls of the first group of pores yields up some adsorbate, owing to the decrease in its thickness from t, to t. Similarly, when the relative pressure is further reduced to pj/p°, the decrement (nj-Wj) in the uptake will include contributions from the walls of both groups 1 and 2 (as the film thins down from tj to fj), in addition to the amount of capillary condensate lost from the cores of group 3. It is this composite nature of the amount given up at each step which complicates the calculation of the pore size distribution. [Pg.133]

In order to allow for the thinning of the multilayer, it is necessary to assume a pore model so as to be able to apply a correction to Uj, etc., in turn for re-insertion into Equation (3.52). Unfortunately, with the cylindrical model the correction becomes increasingly complicated as desorption proceeds, since the wall area of each group of cores changes progressively as the multilayer thins down. With the slit model, on the other hand, <5/l for a... [Pg.148]

Whereas addition of hydrogen to feedwater helps solve the O2 or ECP problem, other complications develop. An increase in shutdown radiation levels and up to a fivefold increase in operating steam plant radiation levels result from the increased volatiUty of the short-Hved radioactive product nitrogen-16, N, (7.1 s half-life) formed from the coolant passing through the core. Without H2 addition, the in the fluid leaving the reactor core is in the form of nitric acid, HNO with H2 addition, the forms ammonia, NH, which is more volatile than HNO, and thus is carried over with the steam going to the turbine. [Pg.195]

For yet larger motors of frame sizes 710 and above, core losses play a more significant role, and require very effective cooling to dissipate the heat generated. Cooling of larger machines, complicated as it is in view of their size and bulk, necessitating core losses to be restricted as low as possible. [Pg.18]

Yes, but complicated using valence levels for core levels as for XPS... [Pg.23]

The Kodak Advantix format film utilizes PEN. The material has two advantages in that context. First the Advantix film has smaller apertures for the film advance sprockets and PEN locates more accurately in the camera. Secondly its relaxation characteristics are better than PET. When film comes off the cylinder core it has a tendency to curl which can complicate both in-camera use and photofinishing. With PEN, which is a little stiffer than PET, the film relaxes into a flatter profile more quickly. [Pg.175]

Secondly, I wish to counteract anticipated despondency which some of the complexities on the present theoretical scene may perhaps provoke. For this purpose, I wish to invoke the decisive simplicity and definiteness of some of the experimental effects observed within the confines of the above, near ideal systems. This, as I often pointed out elsewhere, is unmatched in the field of crystal growth of simple substances. Complicated as polymers may seem, and subtle as some of the currently relevant theoretical issues, this should not obscure the essential simplicity and reproducibility of the core material. To be specific, the appropriate chains seem to want to fold and know when and how, and it is hardly possible to deflect them from it. Clearly, such purposeful drive towards a predetermined end state should continue to give encouragement to theorists for finding out why Those who are resolved to persevere or those who are newly setting out should find the present review a most welcome source and companion. [Pg.220]

A variety of more complicated compounds having a CH2CH2 linkage to the POSS core have been prepared using methods outlined in Table 29. Thus, epoxides have been made from cyclohexene-terminated POSS (Table 29, entries 1 and 2) and are precursors for the preparation of nanocomposite polymers under ultraviolet irradiation (Figure 43). ... [Pg.74]

A very important complication in interpreting ice core records, and in defining depth-age relations, is the fact that snow transforms to ice 50 to 100 m below the surfaces of most polar ice sheets. This means the gas trapped in ice is actually younger than the solid ice at the same depth, and that a variety of processes can transport and redistribute gases in this snowy upper layer (called the fim). To imderstand this, and to prepare for subsequent discussions, we must discuss how snow converts to ice near the ice sheet surface. [Pg.468]

There are a wide variety of initial sources of NOs for the ice sheets, including bacterial emissions, biomass burning, photochemical reactions, and lightning. These are generally low-mid-latitude continental sources. This very complicated mixed source renders interpretations of ice-core NOJ" concentrations difficult. A further complication results from possible limitations on delivery of NOT to ice-core sites by atmospheric circulation, due to the large distance from... [Pg.487]

The pentacyclic core 15 of more complicated manzamines was built up by a final ring closure of the thirteen-membered ring lactam in 50% yield. The tetracyclic system and the alkyne unit of the reactant 13 supposed a pre-orientation, an intermediately formed activated pentafluorophenyl ester 14 led to the desired... [Pg.129]

The inclusion of (nonrelativistic) property operators, in combination with relativistic approximation schemes, bears some complications known as the picture-change error (PCE) [67,190,191] as it completely neglects the unitary transformation of that property operator from the original Dirac to the Schrodinger picture. Such PCEs are especially large for properties where the inner (core) part of the valence orbital is probed, for example, nuclear electric field gradients (EEG), which are an important... [Pg.202]


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See also in sourсe #XX -- [ Pg.522 ]




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Complications

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