Definition disadvantages

With only small differences in (Is)max the choice of the binder system is influenced by processability, physical properties, and propellant density. Thus, with the polyether binder an Is of 247 is reached with about 14% binder, but with the polyester the same Is is obtained with 11.5% binder, which is a definite disadvantage in terms of processability and mechanical properties. The higher Is with the polybutadiene binder is realized only at high solids loadings, but owing to its lower density, processability is still satisfactory. 

On the other hand, the photographic methods have two definite disadvantages. Droplets smaller than 20 microns cannot be photographed satisfactorily in a fast-moving spray, and the photograph records the spatial rather than the more important temporal distribution of drops. The latter objection can be overcome if drop velocities are known, but data on velocities are not easily obtained. Another serious problem is determination of whether a droplet is in or out of focus when it appears near the boundary of the field... 

The ability of bone char to function as an alkaline buffer, so essential in sucrose refining, is a definite disadvantage in the refining of dextrose where it is desirable to operate on the acid side of pH 6. It has been shown that the optimum pH range is as low as 3.0 to 3.5.3 However, since solutions of this acidity would attack storage vessels, char filters and pipe lines, it is impractical to operate in the optimum pH range unless acid resistant equipment is employed. Consequently pH 5 is a practical lower limit for the process. 

Brewster polarizers are almost not used anymore in IR spectroscopy since their relatively big sizes represent a definite disadvantage. Nowadays they are practically replaced by the convenient grid polarizers. 

An ICAP emission spectrometer in a commercial analytical laboratory can successfully provide accurate, precise multielement data (at major, minor and trace levels) for biological and human-related samples for many of the elements of interest for the related disciplines. The relative freedom from interferences is a very positive attribute. The analytical cost of operation is attractive whenever more than four elements must be analyzed in a sample. The inability of the experimental approach used here to provide analytical data for individual species of the elements is a definite disadvantage when this information is required. The primary requirement for ICAP-simultaneous multielement analysis is exceptionally careful analytical sample preparation methods and laboratory techniques. 

Solubility of the polar matrix silica gel increases - similar eluents dis.solves similar solutes . The lifetime of the column decreases either slightly or very much, depending on the stationary-phase material. This is a definite disadvantage. 

Polyester is mainly melt-spun into fibers. A smaller quantity is used for very thin films for the electrical industry. Higher molecular weight poly(ethylene terephthalate) with added nucleating agents (salts of carboxylic acids) can also be used as thermoplastic synthetics. A definite disadvantage of polyester fiber is that it yellows in light. The mechanism for this process... 

The dedicated machine-mounted drying arrangement has some definite disadvantages too ... 

The literature on rust inhibitors is mixed. Some sources view them as quite effective against corrosion, although they also have some undesirable effects when properly used. Others, however, view rust inhibitors as a definite disadvantage. Which chemicals are suitable inhibitors is also an area of much discussion. 

The plate assay method for antibiotics is the most widely used and accepted method employing the diffusion technique. Its advantages lie in its simplicity as to labor and equipment. It has definite disadvantages in that the assay is affected by various salts, surface active agents, and solvents which tend to change diffusion characteristics of the antibiotics. With alterations in the diffusion characteristics the dose response curves of the sample and standard will no longer be parallel and the assay itself would be invalid. 

The moving boundary method has the definite disadvantage that the separation is never complete there is always a dead volume containing the original solution in the bottom of the U-tube. For the same reason, only the fastest and the slowest components in a mixture may be obtained in a pure state in one operation. This limitation of the method lies in the principle, stabilization of boundaries by gravity the density of the solution must increase downward at every boundary the opposite causes... 

One point should be noted about the design the steam from the reactor would not be suitable for generating electricity since it would not be hot enough. This meant adding oil-fired superheaters, which made the plant less efficient. Some early American light water reactors did exactly this, but from the engineering point of view, this was a definite disadvantage. 

One definite disadvantage that the Organic Chemicals Department had was that during the 1960s it was involved in several totally unrelated businesses (fluorocarbons, petroleum additives, dyes and chemical intermediates). When people were transferred from one area to another, they brought little useful experience with them. There was reputedly some crossfertilization, but it did not do much for moving businesses along. DuPont then was reluctant... 

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