Six unique features

Molecular motions (rotation, translation, and vibration) of a water molecule also turn out to be quite different from those of other common liquids. Here all the six unique features of an individual water molecule outlined in Chapter 1 manifest themselves in diverse ways. As we discuss below, not only is the mechanism of displacements of individual water molecules different, but the collective dynamics and dynamical response of bulk water are also different. For example, the rotational motion of an individual water molecule contains a surprising jump component and vibrational energy relaxation of the O—H mode involves a cascading effect mediated by anharmonicity of the bond. These motions are reflected in many important processes such as electrical conductivity, solvation dynamics, and chemical reactions in aqueous medium. 

Understanding the origin of the anomalous properties of water has turned out to be an extraordinarily difficult task - a task that is only partly completed. Nevertheless, we need to make a beginning, with whatever understanding we have acquired of bulk water [1-5], in our attempt to understand the diverse (and myriad) roles that water plays in many complex environments, including biology. We discuss below six unique features that can be held responsible for many of the properties of water. But first we present a few of the essential details about a water molecule so that those features can be understood and appreciated. 

As mentioned above, we can make a list of six unique features of water that are responsible for many of its abilities and properties. We now list these properties. 

Some ten years later, Darwish and Braverman50,51 undertook a more extensive study of this rearrangement, which has revealed some unique features. These investigators examined the behavior of six different esters, namely allyl, crotyl, a-methylallyl, racemic and optically active a, y-dimethylallyl, cinnamyl and a-phenylallyl 2,6-dimethylbenzene-sulfinates under various reaction conditions. 

Halsted et al. (20) published results of their study in a group of 15 men who were rejected at the Iranian Army Induction Center because of malnutrition. A unique feature was that all were 19 or 20 years of age. Their clinical features were similar to those of zinc-deficient dwarfs reported earlier by Prasad et al. (6,7). They were studied for 6 to 12 months. One group was given a well-balanced nutritious diet containing ample animal protein plus a placebo capsule. A second group was given the same diet plus the diet alone without additional medication for six months, followed by the diet plus zinc for another six-month period. 

An example is the thermal decomposition of a metal onto a support involving an ammine complex having the formula [Me(NH3)6] C03 where Me is the metal. In this complex, six ammonia molecules coordinate symmetrically from the central metal ion and form an octahedral structure. It is therefore possible to form small metal crystallite-sized catalyst by using ammine complex as a precursor. The unique features of a catalyst made from ammine decomposition include uniform distribution of metal throughout the catalyst particles, smooth and homogenous surface morphology, and high thermal stability. ... 

As far as we know the Earth is the only planet inhabited by life. Why is this so What are Earth s unique features that confer on it the status of a habitable planet Here we identify six features which make Earth home to life. 

Liquid water is different from other liquids. Unique (and often termed anomalous) properties of water originate ultimately from the unique molecular features of water. We have made a list of six such features which combine to give rise to the unusual properties of water. The list itself may not be unique or exhaustive but we think that it provides a starting point to rationalize the properties of water. 

An outstanding example is the sunflower seed. The industrial ammonia synthesis process mentioned under Example 0.1 is still technologically too primitive in comparison to the millimetersized sunflower seed. This seed, after being planted and exposed to sufficient nutrients and solar energy, establishes an oil factory, a cellulose factory, and a paint factory within six months. It has several process control units, but the most explicit one makes the sunflower follow the sun. It is the chemist/chemical engineer s dream to emulate this unique feature of the sunflower and be able to synthesize on demand chemicals, as much as, when and where needed. As we lamented earlier, it is still a dream. 

A typical example of micelle formation with a PSs-PAAg ionic star-block copolymer is that described by Zubarev and Teng [240]. The unique feature of their copolymer, with M =35,000, is that the arms are not randomly linked to the core, but as six pairs of PS/PAA blocks linked to a central core. 

Today, we know that the six electrons are shared eqnaUy among the six carbon atoms and that all the carbon-carbon bonds in benzene are identical due to resonance. This unique feature of benzene makes it especially stable. Benzene is most often represented as a skeletal formula, which shows a hexagon with a circle in the center. Some of the ways to represent benzene are shown as follows ... 

Since 1987, a team of six Du Pont staff (a system analyst and five technical information speciaUsts) and twelve CAS staff (five chemists and seven system analysts) designed and built the database and converted 160,000 substances, abstracts and indexing records for over 112,000 documents, and a 26,000-term thesaurus to create SCION (Scientific Corporate Information Online). The database has the unique feature that both Du Pont proprietary files as well as publicly available files on STN International can be searched with the same command language, MESSENGER. SCION consists of a chemical file and a document file. 

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