Carrier solvents additives

One of the principal factors to be considered is the concentration of pigment m the dispersion concentrate. Compatibility of the carrier (solvent additives, etc) used in the preparation of concentrated dispersion and that used in the finished color product also plays an important role. In some cases this can be difficult because the earners having the best performance, from the standpoint of processing, could be poor in the application systems. However, in the majority of the applications, particularly in coatings and colored plastics, the concentration of the pigment in the finished product is quite low. and the incompatibility problem is easily overcome. 

With the increasing emphasis on energy conservation and environmental considerations, additives for fuels that can correct combustion-related problems have aroused considerable interest. Many commercial fuel additives are combinations of organometaHics, dispersants, emulsifiers, and carrier solvents. The organometaHic, often a metal soap, acts as a combustion catalyst, increasing efficiency with reduction of smoke, deposits, and corrosion. 

The Council and the Commission must adopt positive fists of additives, authorised to the exclusion of all others, fists of foods in which the additives may be used with conditions of use, and rules on carrier solvents. The Standing Committee on Foodstuffs must approve adoption of purity criteria for listed additives and, if necessary, methods of analysis to verily these purity criteria, sampling procedures and methods of analysis for food additives in food. The directive includes provisions that a member state may temporarily suspend or restrict application of an authorisation if it has detailed grounds for considering that the use of the additive in food, although permitted, endangers health. The... 

Carriers including carrier solvents These are used to dissolve, dilute or otherwise physically modify a food additive without altering its technological function (and without exerting any technological effect themselves) in order to facilitate its handling, application or use... 

Benzene and its derivatives are used widely throughout the chemical industry as solvents and raw materials. Mono-, di-, and trichlorobenzenes are used directly as pesticides for their insecticidal and fungicidal properties. Benzene, toluene, and chlorobenzene are used as raw materials in the synthesis of at least 15 pesticides, although their main use is as a carrier solvent in 76 processes. Additional priority pollutant aromatics and chlorinated aromatics exist as impurities or as reaction byproducts because of the reactions of the basic raw materials and solvent compounds. 

The Diluent. The diluent or carrier solvent is mainly required as a diluting medium, to lower the viscosity of the organic phase and facilitate the contact between the two phases. It may also have some additional properties and should ... 

Perfluorocarbons are a class of organic compounds in which all of the hydrogen atoms are replaced with fluorine atoms. They possess unique properties that make them very useful as dispersants, carrier solvents, and processing solvent additives. Their lack of chlorine or bromine atoms results in zero-ozone-depletion potential. 

Thermal Desorption Thermal desorption is an alternative GC inlet system particularly used for VOC analysis. However, the analytes subjected to thermal desorption must be thermally stable to achieve successful analysis. Otherwise, decomposition occurs. This technique is mainly used for determination of volatiles in the air. Such a methodology requires sample collection onto sohd sorbents, then desorption of analytes and GC analysis. Traditionally, activated charcoal was used as a sorbent followed by extraction with carbon disulfide. However, solvent desorption involves re-dilution of the VOCs, thus partially negating the enrichment effect. Therefore, the sampling method is to pump a sample of gas (air) through the sorbent tube containing certain sorbents in order to concentrate the VOC. Afterwards, the sample tube is placed in thermal desorber oven and the analytes are released from the sorbent by application of high temperature and a flow of carrier gas. Additionally, desorbed compounds are refocused in a cold trap and then released into the GC column. Such a two-step thermal desorption process provides a narrow chromatographic band at the head of the column. 

The urea formed during the reaction is water soluble and can be extracted with water if the peptide synthesis is performed in organic solvents. It can be removed by dialysis or by gel filtration when used to couple haptens to high molecular weight carriers. In addition to the use of carbodiimides for the direct formation of peptide bonds, they can also be applied for the preparation of active esters, such as hydroxysuccinimide... 

If a carrier solvent has been used, it is critical to compare the solvent control to the control treatment to ensure comparability. The common student s t-test can be used to compare the two groups. If any differences exist, then the solvent control must be used as the basis of comparison. Unfortunately, a t-test is not particularly powerful with typical data sets. In addition, multiple endpoints are usually assessed in a chronic toxicity test. The change of a Type 2 error, stating that a difference exists when it does not, is a real possibility with multiple endpoints under consideration. 

For characterization and exploitation of the diamide-phase system, a chiral diamide, e,g., (Ill) was examined as a modifier in the mobile phase (solvent) in conjunction with a non-bonded (bare) silica. Such a chiral carrier separated enantiomeric N-acyl-d-amino acid esters and amides with separation factors comparable to those for bonded stationary phase systems. The resolution can be as cribed to diastereomeric complexation through amide-amide hydrogen bonding between the amide additive and enantiomeric solute molecules in the carrier solvent, followed by separation of the diastereomeric complexes by the (achiral) silica phase. This process should be applicable as widely as that involving chiral diamide-bonded stationary phase systems. 

A disadvantage of IC1 is its high oxidation potential and the necessity for carrier iodide addition. Iodine monofluoride ( IF), obtained by reaction of F2 gas with Na I in perfluorinated solvents (Goenen et ai, 1995), seems to be a good alternative, since it can be used directly, without further purification or isolation procedures. 

Individual extracts may be flammable, toxic, or otherwise hazardous (e.g., benzaldehyde is a combustible liquid with an irritating odour in high concentrations, vanillin is a flammable solid, and beverage acidulants are corrosive) but it is the extensive use of solvents, like alcohols and ethers, to carry the extracts that presents the usual hazard in transportation. However, even if the extracts, carriers, or additives are not directly hazardous, they may be so irritating and obnoxious that they present a hazard in transportation to passen-... 

Specifications for identity and purity of food additives (carrier solvents, emulsifiers and stabilizers, enzyme preparations, flavouring agents, food colours, sweetening agents, and other food additives). FAO Food and Nutrition Paper, No. 19, 1981. 

Definition Methyl ester of rapeseed oil Uses Lubricant in metalworking and agric. adjuvants carrier, solvent for printing inks, leather treating compds. additive in adhesives for food production or pkg. 

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