Crystals ball-like

Figure4.8 SEM cross-section (a) and top surface (b) images of lollipop-like V205-Zn0 core-shell structures. The top heads are V2O5 crystal balls and the stems are ZnO nanorods. Reprinted from [117] (2010) American Chemical Society.

As the main theme of this meeting is to assess and consolidate past achievements in various key areas of inorganic/organo-metallic chemistry, with the objective of gazing deep and hard into the futuristic chemical crystal ball of the 21st century, the purpose of my presentation will be to focus attention on pivotal developments in the field of transition metal atom/metal cluster chemistry over the past decade and then to attempt to project and forecast some of the more promising directions that the area is likely to follow in the years ahead. 

At the start of a new century it is possible to look at likely developments in the chlor-alkali business although there is some crystal ball forecasting rather than usual market research employed. 

The popularity of Monte Carlo for risk-based uncertainty analysis is somewhat driven by the fact that Monte Carlo is fundamentally easy to implement, particularly with the advent of the personal computer, and graphically based software like Crystal Ball (www.decisioneering.com) and Risk (www.palisade. com/risk.html). The availability of such software systems generally promotes the use of uncertainty analysis in ecological risk assessments, reducing the amount of mathematical and statistical knowledge required of the user to implement the... 

Students of the occult generally agree that much of fortune-telling has nothing to do with the ability of the practitioner to forecast the future On the contrary, the uncanny ability of the gypsy woman to tell the customer what he or she would like to hear is based on a shrewd ability to assess the facts contributed by the customer and to construct these facts into a plausible sequence of possibilities. The dark tent, crystal ball, and fancy costuming are merely trimmings to enhance the effect ... 

I moved a chair over to the big mirror in the wall of books. Mirrors themselves are no more magical than crystal balls, but both can be used for occult purposes, like the piece of chalk I used to draw a pentacle around myself and the chair. I sat down, tried some deep breaths, and then uttered my first call, summoning Putrid (not his real name) to be manifest in the mirror before me. 

He hurried off back to the atelier like a little black ant and went straight to the crystal ball on its stand, whipping away the cover. Then he adjusted himself on his chair, laid his staff on the floor beside him, and rubbed his hands expectantly. He enjoys a soothsaying as much as I detest it. 

We conclude our crystal ball gazing with a list of research topics or approaches that we feel are likely to be of importance in the future. After reading this book, it should be obvious that this list is far from exhaustive. Our list follows the general organization of this book and is submitted in a terse format without details or justification. 

Besides the mobility on the cluster surface in solution the ball-like character of the huge molecules obviously prevents crystallization. If we assume a closest packed structure for the M55 cluster sphere in a crystal, then there would exist octahedral lattice vacancies with a diameter of 8-9 Al There is some hope to find ligands causing inter-molecular interactions and thus facilitating crystallization. 

Figure 3, Diamond crystals grown from 1.5 vol. % CH4-H2 at 10 torr using a combined microwave and hot-filament CVD method, (a) Cube and octahedral faces, (b) twinned crystals with pseudo fivefold symmetry, (c) ball-like diamond grown at high supersaturations the scale in (a)-(b) is 12 pm and in (c) is 15 pm. (Reproduced u/idt pemtissionf American Association far the Advancement of Science, 1988.)...

In another HFCVD experiment, the influence of gas pressure on diamond film coverage and crystal size was studied. As shown in Fig. 6, the crystal size and surface coverage attain a maximum at 1.3 kPa ( 10 torr). Crystal quality and phase purity are both optimized around a pressure value of 4 kPa (30 torr). At 665 Pa ( 5 torr) an amorphous film covers the substrate and ball-like particles form. 

Upon retuning home, they submitted the crystal ball to the psychic examination of proven seers or seeresses. Every time these seers saw the crystal ball glow red like a ruby. Every time the phenomenon faded little by little, and disappeared totally at the end of around ten to twelve hours. The seers never saw ordinary balls (presented to them as proof), which had not been exposed to the Holy Species, presenting th is strange phenomenon. 

The preparation of black phosphorus is carried out in a glass ampul A (see Fig. 8) of 7-cm. length and 2-cm. i.d. Inside the ampul are five steel balls, like the ones used in ball bearings. Twenty grams of mercury and about 50 mg. of black phosphorus (seed crystals) in pieces, not pulverized, are placed in the ampul. About 20 g. of purified white phosphorus is then transferred under an inert atmosphere to B and the apparatus sealed at C. 

We do not claim to hold a crystal ball however, some aspects of selection, training, and development are likely to stay the same, while others are likely to change. In our view, those that will stay the same are based on well-established research results and apply independently of increasing globalization and accelerating technological development. Those that wiU change lack these attributes. 

Plastic crystals are characterized by orientational disorder but positional order of the structural motif. Molecules of plastic crystals are close to spherical, which are generally packed in body- or face-centered cubic structures [7]. T)q)ical examples are proAdded by the structure of ball-like hydrocarbon molecules as adamantane and norbornane. The name plastic crystals derives from the softness and easy of deformation of these materials, due to the large number of slip planes in close packed structures [5,7]. 

The osmilation of fullerenes has been important not only for investigating the reactivity of these clusters but also for obtaining for the first time an X-ray crystallographic analysis at atomic resolution level of the C o framework. As mentioned above, orientational disorder in the fullerene crystals-arising fundamentally from their nearly spherical symmetry which permits these ball-like molecules to rotate freely - systematically prevents us from obtaining the atomic... 

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