Formic acid solution preparation

See Table III.) Bismuth formate Bi(OOCH)3 is prepared by reacting bismuth oxide with a 40% formic acid solution under reflux conditions (50, 64). The solid-state structure shows three different Bi-0 distance ranges [avg. 2.38, 2.52, and 2.77 A] and all oxygen atoms interacting with bismuth, which occupies a six-coordinate, distorted octahedral environment. The octahedra are linked via the carbon centers re-... 

Oriented, regenerated chitin prepared by spinning from a formic acid solution showed reflections corresponding to spacings of 0.25, 0.34, 0.51, and 1.01 nm on the meridian, and 0.46 and 1.12 nm on the equator. It was suggested that the regenerated chitin may have the same structure as native chitin. 

A test solution having a concentration of 40 mg/mL in 15 N formic acid is prepared, and the optical rotation determined according to General Test <781 S>. The specific rotation is to be between +14.5° and +16.5°, determined at 20°C within 30 minutes after preparation of the solution. 

Preparation of the Dye. Acid IV (0.1 mole) is diazotized (like sul-fanilic acid) and to the diazo solution is added a formic acid solution of o-naphthylamine. The coupling reaction is carried out for 24 hours, and the reaction mixture is then heated to boiling. The dye is salted out from the hot solution and rqprecipitated from alkaline solution. The precipitated monoazo dye is then diazotized indirectly, and the diazo compound is filtered off and coupled with Cleve acid in the presence of formic acid. After 24 hours (the coupling reaction is slow), the solu-... 

The methodology is similar to that described above for electrophoresis at pH 4.4. This methodology is specific for the analysis of sulfates. This is carried out using a formic acid solution pH 2.2 prepared by adding 12.5 mL formic acid to 38 mL acetic acid in 1 L water. This solution was used in the place of acetate buffer using the same methodology described above. 

The performic acid is prepared in the usual manner by allowing a mixture of 1.0 ml of 30% (w/v) H2O2 and 9.0 ml of 88% (w/v) formic acid to stand at room temperature for 1 hr, after which it is cooled to 0°C. A known amount of protein, usually the amount used for routine hydrolysates, is dissolved in 1 to 2 ml of the reagent in a cooled hydrolysis tube. If the protein does not dissolve readily in the cold reagent, it can usually be dissolved first in 0.1 ml of 100% formic acid at room temperature. The mixture is kept at 0°C for 4 hr after which performic acid is destroyed by the addition of 0.15 ml of cold 48 % (w/v) HBr per ml of performic acid reagent used. The bromine which forms, as well as the formic acid solution, can best be removed from the hydrolysis tube by rotary evaporation under high vacuum (mechanical pump) at 40°C with NaOH pellets in the condenser trap the condenser should be cooled with dry ice in ethanol. Acid hydrolysis of the oxidized sample and analysis of the resulting hydrolysates are performed in the usual manner ( 2.1.2). 

FIGURE 12.2 Variation of open-circuit potential with time for I iOj film electrodes, prepared by anodization of Ti, in contact with BS. Base solution SI and S2 0.1 and 0.5 mM salicylic acid Ml and M2 1 and 10 mM methanol FI and F2 1 and 10 mM formic acid solutions. (From Li and Shen, 2006. J. Solid State Electrochem. 10, 980-986, with permission from Springer.)... 

This method is not suited to the preparation of 2-unsubstituted oxazoles the main difficulty is the preparation of the acyloin formates themselves. Bredereck and Gompper94 introduced a new method of synthesizing the acyloin formates (54) by the treatment of acyloins in formic acid solution in the cold with either phosphorus trichloride or thionyl chloride. The yields in the three reported cases are 61-91%. These a-formyloxy ketones on boiling with formamide in formic acid afford the corresponding oxazoles. unsubstituted in the 2-position, in 61-75% yields.94... 

Since preparation of this manuscript, subsequent studies were completed (11) on new segmented polyurethanes of type I made exclusively from polyethylene oxide diols, ethylene diamine, and 1,4-cyclohexane diisocyanate (CHDI) (no other diisocyanate was used). They were synthesized in toluene (not DMSO/pentanone)withdibutyltin dilaurate as catalyst (no catalyst was used to synthesize the polymers listed in Tables II and III) and eventually cast from hexafluroisopropanol or formic acid solutions (not DMF in which they were insoluble). 

In general, azo-, hydrazo-, and amido-compounds result from the electrolytic reduction of nitro-com-pounds. In this way Kendall obtained aniline from nitro-benzene, and Elbs and Haussermann prepared the normal reduction products of nitfo-phenol. The formation of azoxy-, azo-, amido-, or hydrazo-com-pounds was dependent upon whether acid or alkaline solutions were employed. If nitro-benzene is reduced in a concentrated acetic or formic acid solution, to which a few drops of concentrated sulphuric acid (to increase the conductivity) have been added, the corresponding salts of benzidene result a fact further confirmed by Lob. ... 

Nylon-6 electrospun fiber webs by the in situ pol5mierization of polyaniline were prepared. ° PANl-nylon 6 electrospun fiber web with various PANl and nylon contents in a formic acid solution were prepared, when the concentration of PANl nanoparticles was from 2 to 8 wt %, the PANl-nylon 6 electrospun nanofibers were composed of two kinds of phases. When the concentration of PANl nanoparti-... 

Formic acid, HCOOH, (M. Wt. 46.03). To prepare an approx. IM solution, dilute 38.5 ml 98—100% formic acid or 42.4 ml 90% formic acid to 1 litre. Check by titration with NaOH against phenolphthalein. Formic acid/sodium formate buffers are prepared by partial neutrahzation of formic acid solutions with NaOH. 

What volume of a 5.75 M formic acid solution should be used to prepare 2.00 L of a 1.00 M formic acid solution ... 

Ki CS, Baek DH, Gang KD, Lee KH, Um IC, Park YH (2005) Characterization of gelatin nanofiber prepared from gelatin-formic acid solution. Polymer 46 5094-5102... 

Lead formate separates from aqueous solution without water of crystallisation. It can therefore be used for the preparation of anhydrous formic acid. For this purpose, the powdered lead formate is placed in the inner tube of an ordinary jacketed cond ser, and there held loosely in position by plugs of glass-wool. The condenser is then clamped in an oblique position and the lower end fitted into a receiver closed with a calcium chloride tube. A current of dry hydrogen sulphide is passed down the inner tube of the condenser, whilst steam is passed through the jacket. The formic acid which is liberated... 

Cobalt(II) nitrate hexahydrate [10026-22-9], Co(N02)2 6H20, is a dark reddish to reddish brown, monoclinic crystalline material containing about 20% cobalt. It has a high solubiUty in water and solutions containing 14 or 15% cobalt are commonly used in commerce. Cobalt nitrate can be prepared by dissolution of the simple oxide or carbonate in nitric acid, but more often it is produced by direct oxidation of the metal with nitric acid. Dissolution of cobalt(III) and mixed valence oxides in nitric acid occurs in the presence of formic acid (5). The ttihydrate forms at 55°C from a melt of the hexahydrate. The nitrate is used in electronics as an additive in nickel—ca dmium batteries (qv), in ceramics (qv), and in the production of vitamin B 2 [68-19-9] (see Vitamins, VITAMIN B22)-... 

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