Overall effect

As is suggested frequently , this term might well result from the restriction of the hydrogen bonding possibilities experienced by the water molecules in the first hydration shell. For each individual water molecule this is probably a relatively small effect, but due to the small size of the water molecules, a large number of them are entangled in the first hydration shell, so that the overall effect is appreciable. This theory is in perfect agreement with the observation that the entropy of hydration of a nonpolar molecule depends linearly on the number of water molecules in the first hydration shell ". ... 

Now the overall effects due to hydrogen bonding, dipole moment, acid-base properties, and molecular configuration can be expressed as... 

Overall Effects of lon/Molecule Collisions and the Gse of Ion Transmission Guides... 

The overall effect, aside from the change in the polymer composition, is a decrease in the rate of monomer reaction, the kinetic chain length, and the polymer molecular weight (83). 

Pressure. Within limits, pressure may have Htfle effect in air-sparged LPO reactors. Consider the case where the pressure is high enough to supply oxygen to the Hquid at a reasonable rate and to maintain the gas holdup relatively low. If pressure is doubled, the concentration of oxygen in the bubbles is approximately doubled and the rate of oxygen deHvery from each bubble is also approximately doubled in the mass-transfer rate-limited zone. The total number of bubbles, however, is approximately halved. The overall effect, therefore, can be small. The optimum pressure is likely to be determined by the permissible maximum gas holdup and/or the desirable maximum vapor load in the vent gas. 

The interaction of all these factors makes it difficult to predict an overall effect of conservation tillage on the potential leaching of a pesticide compared to that in a conventionally tilled field. However, it was found that a prolonged rain immediately after appHcation resulted in short-term levels of pesticide in groundwater to be greater under no-tiU than under conventional till plots, which suggested that preferential transport in no-tiU had occurred... 

The overall effect in most animals is to stimulate intestinal absorption of calcium with a concomitant increase in semm calcium and a reduction in parathyroid hormone (PTH). Modest hypercalcemia allows the glomerular filtration rate to remain stable and hypercalciuria to occur because of increased filtered load of calcium and reduction of tubular resorption of calcium with reduced PTH. However, with further increases in semm calcium, the glomerular filtration rate decreases, resulting in an even more rapid increase in semm calcium and the subsequent fall in urinary calcium. 

The adverse effects iaclude digestive disturbances, neurological symptoms, and manifestations of allergic responses. As many as half of the patients taking it are iacapacitated by some of these adverse reactions for several hours. Whether these symptoms are caused by hypersensitivity to the dmg, the parasite, or by a manifestation of the disease is not known. Overall, effects are dose-related and transient. 

DispEcement. In many of the appHcations of chelating agents, the overall effect appears to be a displacement reaction, although the mechanism probably comprises dissociations and recombinations. The basis for many analytical titrations is the displacement of hydrogen ions by a metal, and the displacement of metal by hydrogen ions or other metal ions is a step in metal recovery processes. Some analytical pM indicators function by changing color as one chelant is displaced from its metal by another. 

Quantitative data are available on the effect on electrophilic substitution reactions of the fusion of a benzene ring to the b face of a furan or thiophene ring. The overall effect is to decrease reactivity this decrease is much more pronounced in the case of fusion to a furan than to a thiophene ring. As a consequence the overall reactivities of benzo[Z)]furan and benzo[Z)]thiophene are approximately equal 71AHC(13)235). 

The primaiy goal in performing a HAZOP study is to identify, not analyze or quantify, the hazards in a process. The end product of a study is a hst of concerns and recommendations for prevention of the problem, not an analysis of the occurrence, frequency, overall effects, and the definite solution. If HAZOP is started too late in a project, it can lose effectiveness because ... 

At elevated pressure, the partial pressure of carbon dioxide inhibits calcination, and siilfur dioxide is captured by displacement of the carbonate radical. The overall effect is similar except, as no free hme is formed, the resulting sorbent ash is less alkahne, consisting solely of CaS04 and CaC03. 

Performance based total productive maintenance aims to maximize equipment effectiveness, (overall effectiveness)... 

Alternatively cellulose is produced from wood via wood pulp. A number of processes are used in which the overall effect is the removal of the bulk of the non-cellulosic matter. The most widely used are the sulphite process, which uses a solution of calcium bisulphite and sulphur dioxide, the soda process using sodium hydroxide and the sulphate process using a solution of sodium hydroxide and sodium sulphide. (The term sulphate process is used since sodium sulphate is the source of the sulphide.) For chemical purposes the sulphite process is most commonly used. As normally prepared these pulps contain about 88-90% alpha-cellulose but this may be increased by alkaline purification and bleaching. 

The LUMO, which is the frontier orbital in reactions with nucleophiles, has a larger coefficient on the /3-carbon atom, whereas the two occupied orbitals are distorted in such a way as to have larger coefficients on oxygen. The overall effect is that the LUMO is relatively low-lying and has a high coefficient on the /3-carbon atom. The frontier orbital theory therefore predicts that nucleophiles will react preferentially at the /3-carbon atom. 

Detailed analysis of isotope effects reveals that there are many other factors that can contribute to the overall effect in addition to the dominant change in bond vibrations. For that reason, it is not possible to quantitatively predict the magnitude of either primary or seconday isotope effects for a given reaction. Furthermore, there is not a sharp numerical division between primary and secondary effects, especially in the range between 1 and 2. 

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