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Physical features

Another interesting physical feature relates to the cliromophoric character of fullerenes. Based on the symmetry prohibitions, solutions of [60]fullerene absorb predominantly in the UV region, with distinct maxima at 220, 260 and 330 nm. In contrast to extinction coefficients on the order of 10 cm at these wavelengths, the visible region shows only relatively weak transitions (X at 536 nm s =710 cm ) [142]. [Pg.2419]

The sequence space of proteins is extremely dense. The number of possible protein sequences is 20. It is clear that even by the fastest combinatorial procedure only a very small fraction of such sequences could have been synthesized. Of course, not all of these sequences will encode protein stmctures which for functional purjDoses are constrained to have certain characteristics. A natural question that arises is how do viable protein stmctures emerge from the vast sea of sequence space The two physical features of folded stmctures are (l)in general native proteins are compact but not maximally so. (2) The dense interior of proteins is largely made up of hydrophobic residues and the hydrophilic residues are better accommodated on the surface. These characteristics give the folded stmctures a lower free energy in comparison to all other confonnations. [Pg.2646]

As a consequence of this simplification, certain physical features... [Pg.18]

Pseudohypoparathyroidism is characterized by end-organ resistance to parathyroid hormone (98,108). This disease takes various forms, including Albright s hereditary osteodystrophy, which has unusual physical features and a generalized resistance to G-protein-linked hormones that function through cAMP as a second messenger. This defect is associated with a deficiency in the levels of the a-subunit of (109). Because this defect may be generalized, such patients also have olfactory dysfunction (110). [Pg.283]

In the most general sense, a molecular-based property prediction method can be thought of as any method in which the physical features of a molecule (or... [Pg.247]

Variety of biochemical composition and physical features of milk, as well as compound forms of mineral components foreordain necessity to develop the analytical procedures, in which initial sample state suffers minimum change. Absence of dried milk reference standai ds (RSMs) is an obstacle to use nondestructive XRF for solving the given analytical task. In this communication results of nondestmctive x-ray fluorescence determination of Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Zr in dried milk powders of limited mass (less than 2 g), obtained with using plant RSMs to calibrate, ai e discussed. [Pg.224]

The powerful influence of mechanical factors on these phenomena produces distinctive physical features on affected metal surfaces, as well as determining the locations where the damage occurs. Hence, metal wastage influenced by mechanical factors can be sensitive to geometric shapes and topographical features (surface contours). It is, in this sense, location specific. [Pg.226]

Each approach emphasizes different physical features observed in the fracture process. Either approach, under certain sets of conditions, may provide a satisfactory theory of fragmentation, although neither is apparently complete. [Pg.278]

Much work has been described in the literature on determining which chemical and physical features distinguish coals in terms of reactivity or hydrogenation potential [21]. Coal rank is certainly one of the featiues as shown by the difference between WVGS 13421, which is a medium-volatile bitummous coal, and the lower rank WVGS 13423, which is a high-volatile A bituminous coal. [Pg.218]

The piezoelectric polymer investigations give new physical insight into the nature of the physical process in this class of ferroelectric polymers. The strong nonlinearities in polarization with stress are apparently more a representation of nonlinear compressibility than nonlinear electrical effects. Piezoelectric polarization appears to be linear with stress to volume compressions of tens of percent. The combination of past work on PVDF and future work on copolymers, that have quite different physical features promises to provide an unusually detailed study of such polymers under very large compression. [Pg.137]

This section provides a general overview of the properties of lake systems and presents tlie basic tools needed for modeling of lake water quality. The priiiciptil physical features of a lake are length, depth (i.e., water level), area (both of the water surface and of tire drainage area), and volume. The relationship betw een the flow of a lake or reserv oir and the volume is also an important characteristic. The ratio of the volume to the (volumetric) flow represents tlie hydraulic retention time (i.e., the time it would take to empty out the lake or reservoir if all inputs of water to the lake ceased). This retention time is given by the ratio of the water body volume and tire volumetric flow rate. [Pg.361]

It will be apparent that delay (by physical features) and detection (by alarm, etc.) are entirely separate concepts. They should not be treated as being one and the... [Pg.166]

Table I. The Great Lakes Basin — Physical Features and Population... Table I. The Great Lakes Basin — Physical Features and Population...
The use of Upid bilayers as a relevant model of biological membranes has provided important information on the structure and function of cell membranes. To utilize the function of cell membrane components for practical applications, a stabilization of Upid bilayers is imperative, because free-standing bilayer lipid membranes (BLMs) typically survive for minutes to hours and are very sensitive to vibration and mechanical shocks [156,157]. The following concept introduces S-layer proteins as supporting structures for BLMs (Fig. 15c) with largely retained physical features (e.g., thickness of the bilayer, fluidity). Electrophysical and spectroscopical studies have been performed to assess the appUcation potential of S-layer-supported lipid membranes. The S-layer protein used in aU studies on planar BLMs was isolated fromB. coagulans E38/vl. [Pg.369]

Quantum numbers can be considered to be approximately equivalent to physical features in the atom proposed by Bohr. The principal quantum number corresponds to one of Bohr s circular energy shells. It is related to the average distance of the electrons from the nucleus. Electrons with larger n values are more energetic and farther from the nucleus. [Pg.44]

The spin quantum number brings up a question What physical features of the atom do the quantum numbers represent The answer is ambiguous because of the way quantum numbers were derived. [Pg.48]

The MEM is a powerful new method which is especially useful in cases with limited data sets (powder diffraction). Monte Carlo simulations have shown that the MEM introduces systematic features into the reconstructed density and caution should be exercised when interpreting fine details of an MEM density. It must be emphasized that because the present MEM algorithms do not contain any models, they cannot filter out inconsistencies in the data stemming from systematic errors. The MEM densities may therefore contain non-physical features not only because of systematic bias in the calculation but also because of systematic errors in the data. [Pg.46]

During site characterization, communication is required between the lead and support agencies. The information is mainly on identifying ARARs, and includes a description of the contaminants of concern, the affected media, and any physical features. This information may be supplied by the preliminary site characterization summary or by a letter or other document. [Pg.602]

Kuppa R, Moholkar VS (2010) Physical features of ultrasound-enhanced heterogeneous permanganate oxidation. Ultrason Sonochem 17(1) 123-131... [Pg.265]

General physical features of Earth as listed in Table 1.5. [Pg.416]

Table 1.4 Chemical and physical features of natural waxes... Table 1.4 Chemical and physical features of natural waxes...
Fullerenes, the third allotropic form of carbon along with graphite and diamond, are a novel class of spheroidally shaped molecules made exclusively of carbon atoms. They have generated much enthusiasm and numerous research efforts during the past few years.206 Hence, the chemical and physical features of C6o, also named... [Pg.241]

Figure 1. A ntarctica selected stations and physical features. Figure 1. A ntarctica selected stations and physical features.

See other pages where Physical features is mentioned: [Pg.18]    [Pg.209]    [Pg.97]    [Pg.342]    [Pg.119]    [Pg.1037]    [Pg.361]    [Pg.323]    [Pg.135]    [Pg.167]    [Pg.133]    [Pg.104]    [Pg.32]    [Pg.135]    [Pg.326]    [Pg.328]    [Pg.298]    [Pg.704]    [Pg.153]    [Pg.396]    [Pg.11]    [Pg.15]    [Pg.154]    [Pg.10]    [Pg.260]    [Pg.721]   


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