Deterrency

Strike ranked it 3 in the Top Ten from the first edition because Strike didn t think people would bite at the idea of using such an expensive catalyst as PdCl2. Street chemists are often tightassed when that is the last thing they should be when it comes to production. But this has not been the case with this procedure as Strike has happily found out. At 7.00- 9.00/g, PdCb is still pretty pricey but this has not been a deterrent as many chemists have found. Nor should it be. This procedure works so well that it would, in fact, be stupid not to do it should one happen to work in an accredited, licensed research lab. The following is what Strike first wrote about it. 

Currendy, acrolein is used to control the growth of algae in oil fields and has also been used as an H2S scavenger (96). The abiUty to use acrolein safely in these direct appHcations is a prime concern and is a deterrent to more widespread use. 

Other hydrometaHurgical uses for resin have been smaH in comparison. Replacement of carbon as an adsorbent for gold [7440-57-5] from a cyanide [57-12-5] leached ore has been studied for many years, but remains in limited commercial use. A deterrent has been the failure to develop an efficient and... 

White Chocolate. There is at present no standard of identity in the United States for white chocolate. Virtually all current uses of the term white chocolate do not meet the standards for chocolate, which prescribes the presence of ground cacao nibs. This restrictive requirement has acted as a practical deterrent to companies developing and marketing white chocolate-type products in the United States. When such products have been introduced and marketed in the United States, companies have had to label them with fanciful names to avoid the standardized labeling issues. In other countries where a standard of identity for white chocolate exists and where a minimum amount of cocoa butter is required by law, consumers have available to them a variety of easily recognizable products. 

The high capital cost, about 1500/kW, is the principal deterrent to growth of the IGCC concept. The abiUty to remove up to 99% of the sulfur species from the combustion products make the IGCC an environmentally desirable option as make calcium carbide (see Carbides), from which acetjiene is made. Synthesis gas for methanol and ammonia production is also made from gasification of coke. 

Resoles can be cured by the addition of base or by heat alone. Their shelf life is thus limited, which is a significant deterrent to their use in fiber-reinforced composites. Resoles are often used in unreinforced appHcations in electronics and high moisture areas. 

Copper has been employed as a bactericide, moUuscicide, and fungicide for a long time and is of importance in the control of schistosomiasis (see also Antiparasitic AGENTS, ANTHELMINTICS FUNGICIDES, AGRICULTURAL). Addition of copper to lake water acts as an efficient deterrent to transmittal of the disease by eliminating snails that act as hosts for the responsible parasite. Copper is commonly utilized at ca 0.1 mg/L as an algicide. In fresh water, acute toxicosis in fish is unusual if the copper concentration is below 0.025 mg/L (70) (see Poisons, economic). 

Soybean Protein Isolates. Soybean protein isolates, having a protein content of >90 wt%, are the only vegetable proteins that are widely used in imitation dairy products (1). Most isolates are derived from isoelectric precipitation, so that the soybean protein isolates have properties that are similar to those of casein. They are insoluble at thek isoelectric point, have a relatively high proportion of hydrophobic amino acid residues, and are calcium-sensitive. They differ from casein in that they are heat-denaturable and thus heat-labile. The proteins have relatively good nutritional properties and have been increasingly used as a principal source of protein. A main deterrent to use has been the beany flavor associated with the product. Use is expected to increase in part because of lower cost as compared to caseinates. There has been much research to develop improved soybean protein isolates. 

Distillation of Hquid hydrogen as a method for separating deuterium received early consideration (10,58) because of the excellent fractionation factor that can be attained and the relatively modest power requirements. The cryogenic temperatures, and the requirement that the necessarily large hydrogen feed be extremely pure (traces of air, carbon monoxide, etc, are soHds at Hquid hydrogen temperature) have been deterrents to the use of this process (see... 

Nuclear Magnetic Resonance. AH three hydrogen isotopes have nuclear spins, I 7 0, and consequently can all be used in nmr spectroscopy (Table 4) (see Magnetic spin resonance). Tritium is an even more favorable nucleus for nmr than is H, which is by far the most widely used nucleus in nmr spectroscopy. The radioactivity of T and the ensuing handling problems are a deterrent to widespread use for nmr. Considerable progress has been made in the appHcations of tritium nmr (23,24). 

A small amount of the platinum-group metals is also used in jewelry. The high cost of these metals is an obvious deterrent. 

WE BELIEVE that a need exists for a book to help the chemist or biochemist who wishes to purify the reagents she or he uses. This need is emphasised by the previous lack of any satisfactory central source of references dealing with individual substances. Such a lack must undoubtedly have been a great deterrent to many busy research workers who have been left to decide whether to purify at all, to improvise possible methods, or to take a chance on finding, somewhere in the chemical literature, methods used by some previous investigators. 

Fhe mechanical contact seal is a very positive seal. The seal is normally oil-buffered. The mechanical seal, which is the most complex and expensive, is used where gas leakage to the atmosphere cannot be tolerated. This may be due to the cost of the gas, as in closed-loop refrigeration, or where the process gas is toxic or flammable. The mechanical contact seal requires more power than the other seals, which is a deterrent to its use on lower power compressors. 

Perceived deterrent value to tlie offender and olliers... 

The security system can be considered as layers of protection. Physical barriers and deterrents constitute not only the building stmcture itself, made up of walls, doors, windows, floor and a roof, but the yard around the building and probably a perimeter fence or wall. 

Intruder alarms are designed to give a warning of the presence of an intruder within or attempting to enter the protected area. Alarm systems may act as a deterrent to the casual or opportunist thief but they will do little or nothing to prevent a determined intrusion, and to be effective they must provoke an early response from the appropriate authority (in most cases the police). The warning may be a local audible device, but normally the alarm signal is transmitted by the telephone network to a central station operated by a security company on a 24-hour basis. 

Marine corals secrete organohalogen compounds that act as a feeding deterrent to Starfish. 

In contrast, your car s engine produces small amounts of air pollutants such as NO and copious amounts of C02, which contributes to global warming. On the other hand, there are a couple of deterrents to the use of fuel cells, i.e.—... 

An essential step in the program is production-line control for the early detection of deviations from the standard and the initiation of corrective actions. Objective methods are of value here, but this value may be considerably limited unless methods are sufficiently simple and rapid to give results that may be acted upon during production. For this reason they can generally be little more than qualitative or semiqualitative in character. This should not constitute a deterrent to their development and use, so long as... 

Properties Fire safety continues to be a major performance requirement. Creep and heat distortion are other important properties to be considered. A major deterrent for the architect and builder is lack of common knowledge about plastics physical properties. 

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