Ammonium acetate CAS

At least four chromatographic standards prepared at concentrations equivalent to 50-70% of the limit of quantitation (LOQ) up to the maximum levels of analytes expected in the samples should be prepared and analyzed concurrently with the samples. In LC/MS/MS analysis, the first injection should be that of a standard or reagent blank and should be discarded. Then, the lowest standard should be injected, followed by two to four blanks, control samples, fortifications or investigation samples, followed by another chromatographic standard. This sequence is then repeated until all the samples have been injected. The last injection should be that of a standard. In order to permit unattended analysis of a normal analysis set, we recommend that samples and standards be made up in aqueous solutions of ammonium acetate (ca 5 mM) with up to 25% of an organic modifier such as acetonitrile or methanol if needed. In addition, use of a chilled autosampler maintained at 4 °C provides additional prevention of degradation during analysis. 

Acetate. Ammonium acetate [CAS 631-61-8] NH4C2H3O2, white solid, soluble, formed by reaction of ammonia or NH4OH and acetic acid, reacts upon heating to yield acetamide... 

Copper-ammonium acetate CAS 23087-46-9 Synonyms CAA Classification Inorganic copper Uses Fungicide for control of various diseases of fruit and vegetables... 

PEG 500 tallow aminopropylamine. See PEG-10 tallow aminopropylamine PEG-3 tallow ammonium acetate CAS 91080-64-7... 

Hydroxyqninoline (oxine). Iron (III) ca 30 mg in 25 mL of weakly acidic (HCl) solution). Add a solution of 3 g ammonium acetate in 125 mL water, followed by 12-15mL of reagent solution 2 per cent in 2M acetic (ethanoic) acid. Heat the solution at 80-90°C for 30 minutes, filter and wash the precipitate with 1 per cent acetic acid and with water. Dry at 130-140 °C and weigh as Fe(C9H6ON)3 (Section 11.28). 

Ammonium acetate solution, ca 2M. Dissolve 15.5 g crystallised ammonium acetate in water and dilute to lOOmL. 

The film deposition was carried out at room temperature from an aqueous solution of plumbous acetate, ammonium acetate, and ammonium persulphate, using NH4OH to bring the pH to 6. A trace of AgNOs was added as a catalyst for reaction 7.4 [29]. A film of PbOi ca. 50 nm thick was formed in an hour. Once this initial film was deposited, thicker films could be built up, usually at a somewhat higher pH, in the absence of the AgNOs. The initial film formation appears to be a pure CD reaction. However, electrochemical studies of further film buildup showed that an electroless deposition mechanism, involving two partial electrochemical reactions, was responsible for film formation. 

Ammonium Acetate(Acid), CHsCOONH4CHs-COOH. Long deliq ndls, mp ca 66° Sol in w ale. Can be prepd by distn of the normal... 

The halonitro compounds and the methanol used were of purum or pract. quality from Fluka. The amidine derivatives (in the form of their salts) were purchased from Fluka or Aldrich (purum or pract.). The N,N-dialkyl-formamidine acetates were prepared by analogy to a published procedure (ref. 8) from cyanamide and used as isolated (containing ca. 10% ammonium acetate). 

Sample analysis was performed by using an Applied Biosystems (Foster City, CA) API 3000 triple quadrupole mass spectrometer equipped with a TurboIonSpray source and an Agilent 1100 capillary HPLC system (Palo Alto, CA). The capillary HPLC system included a binary capillary pump with an active micro flow rate control system, an online degasser, and a microplate autosampler. The analytical column was a 300 pm I.D.x 150 mm Zorbax C18 Stablebond capillary column (pore size 100 A and particle size 3.5 pm). The injection volume was 5 pL, and a needle ejection rate of 40 pL/min was used. The pLC flow rate was 6 pL/min. In order to minimize dead volume before the column, the autosampler was programmed to bypass the 8 pL sample loop 1.5 min after injection. The mobile phase consisted of (A) 2 mM ammonium acetate (adjusted to pH 3.2 with formic acid) in 10 90 acetonitrile-water, and (B) 2 mM ammonium acetate in 90 10 acetonitrile-water. The percentage of mobile phase B was held at 32 % for the first minute, increased to 80 % over 8 min, and then increased tol00% over the following 1 min. 

Aliquots (2 ml) of the concentrated extracts are desalted via FPLC (fast protein liquid chromatography) over Sepharose 6 (Pharmacia, Piscataway, NJ) or in gravity-run 10-ml pipettes over BioGel P6DG resin (Bio-Rad, Richmond, CA) in 50 mAf ammonium acetate. Protein extracts are immediately frozen, freeze-dried, and stored with a desiccant. 

Alkaline blotting39 offers the advantage of efficiency but has been criticized83 as producing blots that hybridize 10 times less efficiently than those transferred in 1 M ammonium acetate, 0.02 N NaOH (after two 15-min washes in 0.25 jVHCI, two 20-min washes in 0.5 N NaOH, 1.5 M NaCl, and two 30-min washes in the transfer buffer). In both studies the membrane used was Zeta probe (Bio-Rad, Richmond, CA). 

FNA was synthesized by reaction of /(-naltrexamine (48) with the monomethyl ester of fumaroyl chloride [79], Amine (48) was prepared first from naltrexone by reductive amination with sodium cyanoborohydride in the presence of ammonium acetate to give 6a- and 6/i-epimers (ratio ca. 2 1). Separation was achieved by fractional crystallization [83], An improved synthesis of (48) was reported via the dibenzyliminium salt of naltrexone (46 easily accessible from naltrexone and dibenzylamine) which was reduced with sodium cyanoborohydride to give exclusively the 6/i-epi-mer (47). Catalytic hydrogenolysis afforded /i-naltrexamine (Scheme 3.6) [84]. 

In the literature, different commercial montmorillonites are used, especially for catalytic purposes (KSF or K10 montmorillonites). They are usually acid-treated clays, montmorillonite content of which is rather low. Our x-ray diffraction studies show 44% Ca-montmorillonite content of K10 montmorillonite, and 53% Na-montmorillonite content of KSF montmorillonite the CEC of KSF montmorillonite was found to be 30 meq/100 g by the ammonium acetate method (Richards 1957). A similar value has been given by Abollino et al. (2003). So, in a strict clay science sense, they cannot be considered as montmorillonite. Naturally, this causes no problems in organic chemistry when the main objective is the catalysis of a given reaction. 

The HPLC system used for the analysis of PMP-oligosaccharides included a Waters WISP autosampler and an ABI Model 120 HPLC system. ABI s oligosaccharide HPLC kit-PMP was used for the separation of PMP-oligosaccharides. The kit included a C-18 reversed-phase column, buffer A (10% acetonitrile, 10% 1 M ammonium acetate, pH 5.5) and buffer B (25% acetonitrile, 10% 1 M ammonium acetate, pH 5.5). Elution of PMP-oligosaccharides was monitored at UV 245 nm with the use of a PE Nelson Turbochrom data system (Cupertino, CA) for data acquisition and analysis. 

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