Defining features

Examples of this degradation of bands are shown in Figures 7.44 and 7.45. Figure 7.44(a) shows the rotational fine structure of the Oj] band of the —X Ag system of 1,4-diffuorobenzene, belonging to the >2 point group. The fine structure is in the form of a contour of tens of thousands of unresolved rotational transitions which, nevertheless, shows well-defined features (B is an overlapping weaker band of a similar type). Since Biu = r(T ), as given by Table A.32 in Appendix A, the electronic transition is allowed and... 

Fig. 6. Schematic illustration of the photohthographic patterning process used for defining features in siUcon dioxide using ( ) a positive photoresist that polymerizes light, where ( ) represents the mask (U) Si02 and ( ) Si. Development includes removal of the mask and undeveloped photoresist.

One of the defining features of a new discipline is the publication of textbooks setting out its essentials. In Section 2.1.1, devoted to the emergence of physical chemistry, I pointed out that the first textbook of physical chemistry was not published until 1940, more than half a century after the foundation of the field. Materials science has been better served. In what follows, I propose to omit entirely all textbooks devoted to straight physical metallurgy, of which there have been dozens, say little about straight physics texts, and focus on genuine MSE texts. 

In biology, extracellular matrix (ECM) is the extracellular part of animal tissue that usually provides structural support to the cells in addition to performing various other important functions. ECM is the defining feature of connective tissue in animals. ECM includes the interstitial matrix and the basement membrane. 

Many polymers show partial crystallinity. This is apparent from the study of X-ray diffraction patterns, which for polymers generally show both the sharp features associated with crystalline regions as well as less well-defined features which are characteristic of disordered substances with liquid-like arrangements of molecules. The co-existence of crystalline and amorphous regions is typical of the behaviour of crystalline polymers. 

Early experiments showed that strong electrical forces can strip electrons from atoms. Atoms can also gain electrons under the influence of electrical force. In fact, much of the chemistry that takes place in the world around us involves electrons shifting from one chemical substance to another. Chemical reactions have no effect, however, on the stmctures of nuclei. All atoms of a particular element have the same number of protons in the nucleus, and these do not change during chemical processes. The defining feature of an element, therefore, is the charge carried by the protons in its nucleus. 

Bipolar disorder can be conceptualized as a continuum or spectrum of mood disorders and is not comprised solely of bipolar I disorder.9 They include four subtypes bipolar I (periods of major depressive, manic, and/or mixed episodes) bipolar II (periods of major depression and hypomania) cyclothymic disorder (periods of hypomanic episodes and depressive episodes that do not meet all criteria for diagnosis of a major depressive episode) and bipolar disorder, NOS. The defining feature of bipolar disorders is one or more manic or hypomanic episodes in addition to depressive episodes that are not caused by any medical condition, substance abuse, or other psychiatric disorder.1... 

In recent years, we have extended the nature of our analysis to include certain statistically defined features of the surface electrostatic potential. Our purpose has been to expand the capabilities of V(r) for quantitatively describing macroscopic properties that reflect non-covalent molecular interactions. This has led to the development of the General Interaction Properties Function (GIPF), described by Eq. (3.7) ... 

Lewy body pathology is also the defining feature of several other, rarer diseases, such as Lewy body dysphagia and pure autonomic failure. In these diseases, Lewy bodies and neurites are largely limited to the enteric and peripheral nervous systems. In Parkinson s disease, Lewy body pathology is also present in the enteric and autonomic nervous systems. 

A defining feature for carbenes is the existence of two non-bonding orbitals on one carbon atom. There are two electrons to distribute among these two orbitals and their placement defines the electronic state of the molecule. A simple representation showing the electron occupancy of the non-bonding orbitals is displayed in Fig. 1. The orbital perpendicular to the... 

Fig. 1. Cross-/] structure of amyloid fibrils. (A) Cartoon representation of a cross-/] X-ray diffraction pattern. The defining features are a meridional reflection at 4.7 A and an equatorial reflection on the order of 10 A. The 4.7-A reflection is generally much brighter and sharper than the reflection at 10 A. (B) The cross-/] core structure of amyloid fibrils. Parallel /(-sheets are depicted, but the structure could equivalendy be composed of antiparallel /(-sheets or a mix of parallel and antiparallel. The 4.7-A spacing of /(-strands within each /(-sheet is parallel to the long fibril axis. The depicted 10-A sheet-to-sheet spacing actually ranges from about 5 to 14 A (Fandrich and Dobson, 2002), depending on the size and packing of amino acid side chains. Amyloid fibrils have diameters on the order of 100 A.

Hydrogen bonding and cr-hole bonding can be treated in terms of the Vs,max and 4s,min on a molecular surface. To deal with noncovalent interactions in general, however, it is necessary to go beyond the qualitative pattern of Vs(r) and its Vs,max and Vs.min, and to fully access the whole range of information that Vs(r) contains. This is done by analyzing it in terms of several statistically defined features, adopted over a period of years as we saw specific needs to be addressed. These features are... 

A defining feature of autistic people is their difficulty in communication. Their subjective experience has therefore been glimpsed only darkly. Recently a few people who were autistic have recovered sufficiently to have written accounts of their experiences. The experience they describe is remarkably similar to what would be expected from an ethologically influenced account of autistic behaviour. The translation to and from these two views, the inside and the outside, supports the ethologically influenced description of autistic behaviour. It reminds us how ethologists try and enter the minds of the individuals they observe, and it provides insights into the relationship between subjective experience and publically observable behaviour an essential aspect of intersubjectivity. 

Circulating RBCs lack the enzymes to produce either haem groups or globin chains so the synthesis of haemoglobin is a defining feature of early RBC maturation. Globin chain production is like the formation of any other protein, but a and 3 chain synthesis is closely linked with haem synthesis. 

Now, just the same sort of rationalization can be applied to the radical addition, in that the more favourable secondary radical is predominantly produced. This, in turn, leads to addition of HBr in what is the anti-Markovnikov orientation. The apparent difference is because the electrophile in the ionic mechanism is a proton, and bromide then quenches the resultant cation. In the radical reaction, the attacking species is a bromine atom, and a hydrogen atom is then used to quench the radical. This is effectively a reverse sequence for the addition process but, nevertheless, the stability of the intermediate carbocation or radical is the defining feature. The terminologies Markovnikov or anti-Markovnikov orientation may be confusing and difficult to remember consider the mechanism and it all makes sense. 

Since ab initio calculations are non-trivial for alkanethiols with long chains, methylthiols and other short-chain thiols on Au(lll) have recently received considerable attention. While longer chains with their flexibility and non-negligible chain-chain interactions are essentially a defining feature of SAMs, methylthiols at least supposedly exhibit the same headgroup-substrate interaction. However, due to the different balance of the interactions (chain-chain versus headgroup-substrate), it is not possible to extrapolate the results from short-chain thiols to longer-chain thiols. 

Since the charge is transferred from the TTF HOMO, which mainly derives from the sulfur atoms as mentioned before, the line narrowing is especially important in the S2p NEXAFS. For the energy region of interest here, where clearly defined features are observed (c. 5-6 eV), the C PDOS is dominated by the p-typt contributions with the s- and j -type contributions being much smaller. However, for the S PDOS the weight of the j -type contributions becomes considerably larger. 

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