Primary forces

Grund-immunitat,/. primary immunity, -kapi-tal, n. (original) stock, -konstante, /. fundamental constant, -khrper, m. fundamental or parent substance, -kraft, f. primary force. 

For example, an HHE for a three cylinder application has three crankthrows set at 120°. Piston weights may he balanced or balance weights added to the active crossheads to obtain zero unbalanced primary forces. By comparison, a fixed angle crankshaft requires four crankthrows with either an additional compression cylinder or a balance weight dummy crosshead to obtain acceptable unbalanced forces. ... 

Phospholipids are the most important of these liposomal constituents. Being the major component of cell membranes, phospholipids are composed of a hydrophobic, fatty acid tail, and a hydrophilic head group. The amphipathic nature of these molecules is the primary force that drives the spontaneous formation of bilayers in aqueous solution and holds the vesicles together. 

Type of Crystalline Solid Particles Involved Primary Forces of Attraction Between Particles Boiling Point Electrical Conductivity in Liquid State Other Physical Properties of Crystals Conditions Necessary for Formation Examples... 

A major feature of hydrophobic sorption is the weak interaction between the solute and the solvent. The primary force in hydrophobic sorption appears to be the large entropy change resulting from the removal of a solute from solution. The entropy change is due largely to the destruction of the cavity occupied by the solute in the solvent and the destruction of the structured water shell surrounding the... 

The forces involved in chemistry are essentially electrostatic. They are variants on the Coulomb force. We can distinguish two orders primary forces and secondary forces. Primary forces are those which hold the atoms together in molecules, and the oppositely charged ions in crystalline salts. Respectively, they are known as covalency and electrovalency (or, sometimes, the ionic force). The latter is directly electrostatic, the mutual attraction between Na+ and Cl" in common salt, for example. The former is usually figured as the sharing of an electron-pair between two atoms— Cl-Cl in the chlorine molecule, where the bond stands for a shared pair of electrons. We need quantum mechanics to understand why, in certain circumstances, electron density builds up in the region between the two chlorine atoms. Granted that it does so, we can explain the covalent bond as due to a resultant electrostatic effect. 

The secondary forces are those which operate between molecules which are saturated so far as primary forces are concerned. They correspond to dissociation energies normally in the region 10-50 kJ mol-1. Just because they are relatively weak — easily made connections may be easily broken — they have important consequences. 

Atoms not directly bonded to one another are always much further apart than this. Inherently atoms tend to repel one another see section 4). Only when they are united by strong, primary forces can their repulsion be overcome so as to allow their nuclei to approach to A. When it is merely secondary forces that cause attraction between atoms of neighbouring molecules, much larger separations are found. Because of its connexion with the other b) term in van der Waals equation, his name is also attached to the minimum contact distances between non-bonded atoms. Such distances can be approximately assessed as the sum of radii characteristic of each kind of atom. Table 2 lists a few of these van der Waals radii. 

The classical, or Daltonian, laws of chemical combination depend on strong, primary forces between atoms. Covalency, for instance, nearly always produces discrete molecules, with a well defined structure, and a fixed composition. Only in special cases do the weaker secondary forces give such clear-cut products. The difference is mainly due to the weakness of the forces but it is also due to... 

The DEA currently believes that physicians and pharmacists are the primary forces that allow this criminal behavior to occur. It is their easy access to these controlled substances that creates a pipeline of drug distribution to criminals who sell them on the street. 

Dispersion forces are also the primary forces of attraction between large non-polar molecules. However, as these molecules increase in size, their melting and boiling points rise. For example, methane (CH4) is a small non-polar molecule. It has a very low boiling point and exists as a gas at room temperature. Pentane (C5Hi2) is a larger non-polar molecule. 

After compaction, the green body must be ejected from the die. During die ejection the green body is released from compression at high pressure to very low pressure and then pushed out of the mold. The primary force to be overcome during die ejection is that of wall friction. 

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