Spaghetti

Catalyst particles are usually cylindrical in shape because it is convenient and economical to fonii tliem by extmsion—like spaghetti. Otlier shapes may be dictated by tlie need to minimize tlie resistance to transport of reactants and products in tlie pores tlius, tlie goal may be to have a high ratio of external (peripheral) surface area to particle volume and to minimize the average distance from tlie outside surface to tlie particle centre, witliout having particles tliat are so small tliat tlie pressure drop of reactants flowing tlirough tlie reactor will be excessive. 

Dumm, the hardest of all U.S. wheats, provides semolina for spaghetti, macaroni, and other pasta products. This spring-seeded wheat is grown primarily in the same northern areas as hard red spring, but small winter sown quantities are also grown in Arizona and California. Dumm represents about 5% percent of total U.S. wheat exports. Subclasses are hard amber dumm, amber dumm, and dumm. 

Semolina is the coarsely ground endosperm of dumm wheat. High in protein, it is used by U.S. and ItaHan manufacturers for high quaHty pasta products such as macaroni and spaghetti. In Africa and Latin America it is also used for a dish called couscous. Dumm flour, a by-product in the production of semolina, is used to make commercial American noodles. Farina is the coarsely ground endosperm of hard wheats. It is the prime ingredient in many American breakfast cereals. It is also used by manufacturers for inexpensive pasta. 

Electrical Applications. The largest application of PTFE is for hookup and hookup-type wire used in electronic equipment in the military and aerospace industries. Coaxial cables, the second largest appHcation, use tapes made from fine powder resins and some from granular resin. Interconnecting wire appHcations include airframes. Other electrical appHcations include computer wire, electrical tape, electrical components, and spaghetti tubing. 

HoUow-fiber membranes, therefore, may be divided into two categories (/) open hoUow fibers (Eigs. 2a and 2b) where a gas or Hquid permeates across the fiber waU, while flow of the lumen medium gas or Hquid is not restricted, and (2) loaded fibers (Eig. 2c) where the lumen is flUed with an immobilized soHd, Hquid, or gas. The open hoUow fiber has two basic geometries the first is a loop of fiber or a closed bundle contained ia a pressurized vessel. Gas or Hquid passes through the smaU diameter fiber waU and exits via the open fiber ends. In the second type, fibers are open at both ends. The feed fluid can be circulated on the inside or outside of the relatively large diameter fibers. These so-caUed large capiUary (spaghetti) fibers are used in microfUtration, ultrafUtration (qv), pervaporation, and some low pressure (<1035 kPa = 10 atm) gas appHcations. 

This is because rubber, like many polymers, is composed of long spaghetti-like chains of carbon atoms, all tangled together as we showed in Chapter 5. In the case of rubber, the chains are also lightly cross-linked, as shown in Fig. 5.10. There are covalent bonds along the carbon chain, and where there are occasional cross-links. These are very stiff, but they contribute very little to the overall modulus because when you load the structure it is the flabby Van der Waals bonds between the chains which stretch, and it is these which determine the modulus. 

First, the selection of the wrong pipeline was influenced by a number of factors such as poor labeling and layout. A "spaghetti" of confusing pipework was already on the charging manifold as a result of a number of concurrent... 

The amino acid compositions and sequences of the /3-strands in porin proteins are novel. Polar and nonpolar residues alternate along the /3-strands, with polar residues facing the central pore or cavity of the barrel and nonpolar residues facing out from the barrel where they can interact with the hydrophobic lipid milieu of the membrane. The smallest diameter of the porin channel is about 5 A. Thus, a maltodextrin polymer (composed of two or more glucose units) must pass through the porin in an extended conformation (like a spaghetti strand). 

The rigid chemical structure of a conjugated polymer helps in the movement of electrons. That stiff structure, however, has limited its use. They are like uncooked spaghetti and do not easily entangle themselves. Polymer chain entanglements are necessary to achieve high viscosities, which are required to create fibers out of these polymers. 

Entropy is a measure of disorder in materials. Relaxed polymer chains with a random conformation (shape in space), like cooked spaghetti or a box of fishing worms, have a high degree of entropy, which is favored by Mother Nature. If the chains are stretched out (stressed), the number of conformations the chains can have in space is limited, and the entropy is reduced (see Figure B). The ratio of final length to initial length is denoted a. 

Mr. Harrington s house margarita, which is Sauza Hornitos tequila with fresh strawberries and basil, is part cocktail and part cooking. An herbal, spaghetti-sauce taste underlies the fruit, making an unexpectedly handsome case for a steadily beleaguered drink. 

Meskouris, twenty-seven, stood at his bar at H.K. at 523 Ninth Avenue last Sunday afternoon, talking with a pair of patrons young women, one age twenty-four and the other six months older, as her friend explained, each wearing spaghetti-strap tank tops that revealed tiny, delicate tattoos. 

FIGURE 5.12 The long threadlike molecules of heavy hydrocarbon oils tend to get tangled together like a plate of cooked spaghetti. As a result, the molecules do not move past one another very readily and the liquid is very viscous. 

A typical liquid-crystal molecule, such as p-azoxyanisole, is long and rodlike (14). Their rodlike shape enables the molecules to stack together like dry, uncooked spaghetti they lie parallel to one another but are free to slide past one another along their long axes. Liquid crystals are anisotropic because of this ordering. Anisotropic materials have properties that depend on the direction of measurement. The viscosity of liquid crystals is least in the direction parallel to the long... 

The three-dimensional shape or structure of a polymer is dependent on the shape and type of monomer and the ways the monomers are hnked together. A linear polymer is one in which the monomers are connected in a chainlike manner. Although called linear, such polymers should not be thought of as straight lines. They form random coils as seen in a plate of spaghetti. 

To achieve a compound that meets these feeding requirements, compounders form their product into small pellets. To obtain these small pellets, they use specialized dies consisting of a metal plate with many small holes through which the molten compound is forced. This part of the process is very similar to how spaghetti is formed from pasta dough. To generate small pellets, the extruded strands are chopped into small pieces by rotating blades. 

Fig. 13.1. Mineralogical results of reacting potassium feldspar into a hypothetical water at 25 °C, plotted in linear, semilog (a spaghetti diagram ), and log-log coordinates.

The ultimate goal in reaction modeling is to discover the overall reaction that occurs within a system. Strangely, whereas the results of nearly every published study involving reaction modeling are presented in a spaghetti diagram (see, e.g., Fig. 13.1), few papers report the overall reaction. For this reason, some of the most... 

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