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Nitriles tests

Recently, the spectrum of known nitrilases was significantly enlarged by a screening of 290 prokaryotic nifrilase genes [20]. Of these, 163 were expressed and 125 protein products proved to exhibit nitrilase activities for at least some of the 25 nitriles tested. For instance, nitrilases from Sphingomoms wittichii and Syntrophobacter fumaroxidans were optimal catalysis for the synthesis of (R)-4-methoxy-4-oxo-3-phenylbutanoic acid and 3-oxocyclopenfanecarboxylic acid (building blocks), respectively. [Pg.332]

Boil 5 ml. (5-1 g.) of benzonitrile and 75 ml. of 10% aqueous sodium hydroxide in a 200 ml. flask under a reflux water condenser until no more oily drops of unchanged nitrile run down from the condenser (usually about 40 minutes). Th detach the condenser and boil the solution in the open flask for a few minutes to remove free ammonia, Cool the liquid, and add concentrated hydrochloric acid cautiously until precipitation of benzoic acid is complete. Cool the mixture again thoroughly, filter off the benzoic acid at the pump, and wash well with cold water. Yield, 5 8 g. (almost theoretical). Confirm the identity of the benzoic acid by the tests given on p. 347. The benzoic acid obtained in this way should be pure and have m.p. 121 a portion may if desired be recrystallised from hot water. [Pg.193]

The Rubber Manufacturer s Association (RMA) is a cooperative manufacturiag trade associatioa. Receatly, the RMA has issued a technical buUetia to standardize the reporting of key analytical/quaHty control data on nitrile mbber (22). The various tests commonly mn on nitrile mbber iaclude raw polymer... [Pg.522]

Fig. 4. Tensile fatigue, the Monsanto fatigue-to-failure FTF test, for several elastomers D, FZ A, ethylene—acryflc O, nitrile (NBR) and, FVMQ. Fig. 4. Tensile fatigue, the Monsanto fatigue-to-failure FTF test, for several elastomers D, FZ A, ethylene—acryflc O, nitrile (NBR) and, FVMQ.
Spectral studies at low temperatures enable us to broaden the number of test molecules for surface acidic sites and besides ammonia pyridine and nitriles, to use CO, NO and that do not adsorb at 300 K. [Pg.431]

PTFE gaskets were specified for a section of plant that handled acid. As they ai e fragile and expensive and as an extensive series of tests using water had to be carried out during startup, temporary nitrile rubber gaskets were used during this period. You can guess what happened. One of them was left in position and corroded. [Pg.299]

The above scheme to account for products of nitrile hydrogenation was proposed sixty years ago (80), and with minor variations 28,45,86] has withstood the test of time, It might be expected from the foregoing that, if a nitrile were reduced in the presence of an amine, unsymmetrical amines would result 48), and indeed the reaction provides an excellent way of preparing these amines 49,74). [Pg.95]

IX lists the results of some of these experiments, comparing the nitrile materials with polyethylene, the most widely used plastic container material, and poly (vinyl chloride), which is being used for a number of food packaging applications. Note that in all instances there is an order of magnitude difference between the Lopac container and the other two. For flavorants, which are usually present in very low concentrations, this dilute solution test is probably more significant than a standard permeability test which only measures weight losses of the pure ingredient. [Pg.77]

Tests have been conducted with Monsanto high barrier nitrile resins using the common food simulating solvents (Table X) plus some typical beverages. Conditioning times and temperatures were based on applicable FDA regulations and guidelines (16). [Pg.77]

These objective, quantitative tests have shown that nitrile containers should protect the taste and odor of packaged foods and beverages. But the primary consideration in judging overall package performance, once safety is assured, rests on the subjective evaluations of taste, odor, and appearance. It is well known that the animal senses, in many instances, are far more sensitive than the best instruments and also are capable of integrating the individual effects of the several influences on product quality. [Pg.78]

Our studies of the absorption, permeation, and extraction properties of containers produced from high nitrile barrier resins have demonstrated that they meet or surpass the basic criteria established for retention of taste and odor characteristics of carbonated soft drinks. Sensory tests, which can isolate and identify end results as well as integrate collective effects, have confirmed this judgement and have established the general compatibility of these containers with a variety of beverage products from a taste and odor standpoint. Furthermore, these materials have the excellent physical properties required for containers which will find wide use in food and beverage packaging. [Pg.82]

Analytical Tests for Nitriles (Ref 6J. 1) Redn to the corresponding amines with Na ale identifying the amines by the usual methods ... [Pg.287]

The role of Lewis acids in the formation of oxazoles from diazocarbonyl compounds and nitriles has primarily been studied independently by two groups. Doyle et al. first reported the use of aluminium(III) chloride as a catalyst for the decomposition of diazoketones.<78TL2247> In a more detailed study, a range of Lewis acids was screened for catalytic activity, using diazoacetophenone la and acetonitrile as the test reaction.<80JOC3657> Of the catalysts employed, boron trifluoride etherate was found to be the catalyst of choice, due to the low yield of the 1-halogenated side-product 17 (X = Cl or F) compared to 2-methyI-5-phenyloxazole 18. Unfortunately, it was found that in the case of boron trifluoride etherate, the nitrile had to be used in a ten-fold excess, however the use of antimony(V) fluoride allowed the use of the nitrile in only a three fold excess (Table 1). [Pg.5]

The results of searches of these two chemical classes matched by polymer are presented in Table II. Three candidate polymers (natural rubber, neoprene, and nitrile) were found with 15 models giving acceptable test data. [Pg.67]

The hydrogenation of unsaturated polymers and copolymers in the presence of a catalyst offers a potentially useful method for improving and optimizing the mechanical and chemical resistance properties of diene type polymers and copolymers. Several studies have been published describing results of physical and chemical testing of saturated diene polymers such as polybutadiene and nitrile-butadiene rubber (1-5). These reports indicate that one of the ways to overcome the weaknesses of diene polymers, especially nitrile-butadiene rubber vulcanizate, is by the hydrogenation of carbon-carbon double bonds without the transformation of other functional unsaturation such as nitrile or styrene. [Pg.394]

At the request of an international petroleum company, a major manufacturer and supplier of down-hole equipment performed tests of the various elastomers commonly used in the construction of packers and other oil field tools. Seven of the nine most commonly used thermoplastic materials were found to be completely inert to TKPP solutions. The test included continual immersion in saturated TKPP for 21 days at 280°F. Only two elastomers, Vi-ton and Fluorel, showed any adverse reaction. O-rings made from these two elastomers showed minor cracking at the termination of the test. A listing of the elastomers that tested inert to TKPP solutions include nitrile, saturated nitrile (HNBR), Aflas, Kalrez, PEEK, Glass-filled Teflon, and Ryton. Several of these elastomers are attacked or degraded by conventional clear completion fluids containing calcium and zinc halides. The inertness of commonly employed elastomers to TKPP is an important advantage for TKPP fluids in normal operations. [Pg.632]

A variety of commercial kits and automated systems are available to test the abilities of bacteria to assimilate, ferment, decarboxylate, or cleave selected organic compounds.46 Their reliability for species identification is usually greater with cultures from clinical samples, where a limited number of bacteria are commonly encountered, and less with environmental soil and water samples, where a great many uncommon or previously unidentified species not in the database are likely to be present.29,45 Additional tests beyond those found in the commercial kits may be necessary for example, the hydrolysis of various nitriles and amides is useful for identifying Rhodococcus spp.47 Some commercial kits for clinical use feature antimicrobial susceptibility testing.21... [Pg.5]

Widenor, W. M. "Model Fire Tests on Polyphosphazene Rubber and Polyvinylchloride (PVC)/Nitrile Rubber Foams"... [Pg.242]

The chlorine atom also confers an increased level of resistance to oils, so that the oil resistance of polychloroprene is roughly intermediate between natural rubber and nitrile rubber, and is often sufficient for many applications. Polychloroprene is also self-extinguishing in flame tests. [Pg.93]


See other pages where Nitriles tests is mentioned: [Pg.67]    [Pg.67]    [Pg.240]    [Pg.517]    [Pg.374]    [Pg.863]    [Pg.68]    [Pg.68]    [Pg.108]    [Pg.148]    [Pg.367]    [Pg.369]    [Pg.481]    [Pg.64]    [Pg.64]    [Pg.71]    [Pg.263]    [Pg.283]    [Pg.30]    [Pg.27]    [Pg.361]    [Pg.364]    [Pg.14]    [Pg.130]    [Pg.458]    [Pg.489]    [Pg.41]    [Pg.506]    [Pg.6]   
See also in sourсe #XX -- [ Pg.21 , Pg.22 , Pg.22 , Pg.23 , Pg.24 , Pg.25 , Pg.26 , Pg.27 , Pg.28 , Pg.29 , Pg.30 , Pg.31 , Pg.32 , Pg.33 , Pg.34 , Pg.35 ]




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