Synergistic effect salts

HPC is compatible with many natural and synthetic water-soluble polymers and gums (50). Generally, blends of HPC with another nonionic polymer such as HEC yield water solutions having viscosities in agreement with the calculated value. Blends of HPC and anionic CMC, however, produce solution viscosities greater than calculated. This synergistic effect may be reduced in the presence of dissolved salts or if the pH is below 3 or above 10. 

Dibasic salts of dicyclopentadiene dicarboxylic acid are claimed to be active as corrosion inhibitors [444], Certain salts of fatty acids (metal soaps), together with benzotriazole, are claimed to give synergistic effects for corrosion in antifreeze-agent formulations [446]. 

This accounts for the considerable discrepancy between the alkene Z/E ratio found on work-up and the initial oxaphosphetan ais/trans ratio. By approaching the problem from the starting point of the diastereomeric phosphonium salts (19) and (20), deprotonation studies and crossover experiments showed that the retro-Wittig reaction was only detectable with the erythreo isomer (19) via the cis-oxaphosphetan (17). Furthermore, it was shown that under lithium-salt-free conditions, mixtures of (19) and (20) exhibited stereochemical drift because of a synergistic effect (of undefined mechanism) between the oxaphosphetans (17) and (18) during their decomposition to alkenes. 

Water-soluble nickel salts enter the cells with relative ease but are less effective than crystalline particulates in the cell transformation assay, when using hamster cells [429, 430]. However, an enhancement of viral transformation of cells has been found [431, 432], In addition, a synergistic effect of cigarette smoke extracts, benzo[a]pyrene and nickel sulphate on the morphological transformation of hamster embryo cells has also been obtained [433], It was suggested that nickel salts are more potent as promoters than they are as initiators [434],... 

Consistent with the preceeding acid work, when TMPTA is added to the monomer solutions containing either lithium salt or urea, synergistic effects are observed for the radiation grafting of styrene to polypropylene (Table IV). Again the maximum increase in yield occurs in the monomer solution corresponding to the Trommsdorff peak. 

Table IV. Synergistic Effect of TMPTA with Urea and Inorganic Salt Additives in Grafting Styrene to Polypropylene Initiated by Ionising Radiation3...

When the source of initiation is altered from ionising radiation to UV, analogous additive effects to those previously discussed have been found. For reasonable rates of reaction, sensitisers such as benzoin ethyl ether (B) are required in these UV processes. Thus inclusion of mineral acid or lithium perchlorate in the monomer solution leads to enhancement in the photografting of styrene in methanol to polyethylene or cellulose (Table V). Lithium nitrate is almost as effective as lithium perchlorate as salt additive in these reactions (Table VI), hence the salt additive effect is independent of the anion in this instance. When TMPTA is included with mineral acid in the monomer solution, synergistic effects with the photografting of styrene in methanol to polyethylene are observed (Table VII) consistent with the analogous ionising radiation system. 

Table VIII. Synergistic Effect of Multifunctional Acrylates with Inorganic Salts (L) in Grafting Styrene to Polypropy- lene Initiated by UVa ...

Table XI. Role of UV Dose in Synergistic Effect of Acrylate and Methacrylate Monomers with Inorganic Salts(L) in Photografting Styrene to Polypropylene3...

Synergistic Effects of PFMs with Acids, Salts and Urea. 

Keywords Synergistic effect, Eschke test, Salt spray test, Vapour phase corrosion inhibitor, Weight loss test, Sulphurdioxide test, TU, Aliphatic amines, Aromatic amines. 

In the case of sulfonylation (Scheme 10) [56] and sulfinylation reactions [34], Bi salts proved again to be efficient catalysts. In contrast to the arylsulfonylation, which is under partial control of triflic acid, depending on the substrates, a complete synergistic effect between triflic acid and Bi chloride has been found in the alkanesulfonylation of arenes. In this case, the formation of mixed triflic/alkane-sulfonic anhydrides leads to the active electrophilic species. The formation of the latter exclusively requires the transient formation of a Bi chlorobistriflate species that acts as an intermediate shuttle for triflic acid, leading to the formation of the mixed anhydride precited (Scheme 11). Our experiments have shown that triflic... 

The role of bismuth(III) salts as Lewis acids has only been studied since the late 1980 s. Pioneering work by Dubac, Wada and others paved the way to wide and general methods using bismuth(III) catalysts. The versatile use of bismuth salts in synthesis has clearly been highlighted by the increasing number of publications in the field. The low toxicity of bismuth salts, associated with low cost, make them attractive and practical catalysts to use. Synergistic effects with other Lewis acids have also been recently highlighted. 

Another contributor of MFD is the presence of molecular oxygen. An initial study determined the optimum level of free radical scavenger and chelator required to prevent MFD when added to a meat sample under vacuum 38), Based on those results, subsequent experiments were designed to investigate the synergistic effects of the two compounds, propyl gallate and EDTA (tetrasodium salt), on MFD both in the presence or absence of oxygen. 

Acesulfame-K. This substance (potassium salt of the cyclic sulfano-mide), 6-methyl-l,2,3-oxatJiiazine-4(3H)-l,2.2-dioxide, shown below, was developed by Karl Clauss (IloechstCelanese Corporation, Somerville, New Jersey) in 1967. The compound is a white, odorless, crystalline substance with a sweetening power 200 times that of sucrose. A synergistic effect is produced when the substance is combined with a number of other sweeteners. The substance is calorie-free and not metabolized in the human body. Approval of the use of Acesulfame-K was given by the Food and Drug Administration ( FDA) in the United States in 1983 and it is found in scores... 

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