Standard solution diluting

Standard solutions - make up standard solutions, diluting with nitric... 

To prepare calibration standard solutions, dilute the stock solution in solvent to give the desired final concentrations for the standard curve. 

Transfer as completely as possible the contents of not less than twenty capsules to a tared container, determine the average content weight per capsule, and mix the combined contorts thoroughly. Transfer an accurately weighed portion of the powder, equivalent to about 50 mg of cimetidine, to a 25 ml volumetric flask. Add about 8 ml of methanol, and shake mechanically for 10 minutes. Add 15.0 ml of Internal Standard Solution, dilute to volume with methanol and mix. 

Transfer o50 mg of cimetidine reference standard, accurately weighed, into a 25 ml volumetric flask. Dissolve in 8 ml of methanol, add 15.0 ml of Internal Standard Solution, dilute to volume with methanol, and mix. 

Ra standard solution, diluted to concentration of about 40 Bq per mL, in 0.01 N HN03... 

Sr - 90Y standard solution, diluted in 0.01 N nitric acid to a concentration of about 5 Bq per mL... 

Sr standard solution. Dilute with 0.05 M HN03 to prepare 50 mL of a 90Sr solution at a concentration of about 1 Bq/mL. 

Standard Preparation Transfer 1.0 g of sample into a 100-mL volumetric flask, add 100 pL of Stock Standard Solution, dilute to volume with Cupric Nitrate Solution, and mix. Sonicate, if necessary, to achieve complete solution. 

Standard Solution Dilute a certified Calcium Standard Solution (NIST, or equivalent), quantitatively and stepwise, with water to obtain a Standard Solution containing 0.7 mg of calcium per milliliter of water. Store the Standard Solution in polyethylene bottles because of its instability in glass. 

Assay Determine as directed under Lactose, Appendix X. Transfer about 2 g of sample, accurately weighed, to a 100-mL volumetric flask. Add 10 mL of fructose internal standard solution, dilute to volume with water, and mix. Perform the analysis within 24 h. 

Standard Preparation Dissolve an accurately weighed quantity of USP Thiamine Hydrochloride Reference Standard in Mobile Phase to obtain a solution having a known concentration of about 1 mg/mL. Transfer 20.0 mL of this solution into a 50-mL volumetric flask, add 5.0 mL of Internal Standard Solution, dilute to volume with Mobile Phase, and mix to obtain a Standard Preparation having a known concentration of about 400 p,g/mL. 

Assay Preparation Transfer an accurately weighed quantity of sample containing about 180 mg of lactose into a 10-mL volumetric flask, add 1 mL of the Internal Standard Solution, dilute with water to volume, and mix. 

Acetoin Standard Solutions Dilute Acetoin Stock Solution to prepare the following standards for the standard curve. Use... 

Our initial studies using the kits were disappointing, invariably resulting in modifications of the kits themselves and changes in protocols for use of the kits. Following this initial phase of work, we decided one kit was ready for collaborative study. This first collaborative study involved use of the Neogen Agri-Screen kit. The antibodies have specific ability to bind aflatoxin B, and very low cross reactivity to aflatoxins B, G, and G,. This kit contains Antibody-coated microtiter wells Aflatoxin standard solution Dilution buffer (Tris)... 

Riboflavin standards. Prepare a 100-ppm riboflavin stock solution by accurately weighing about 50 mg riboflavin, transferring to a 500-mL volumetric flask, and diluting to volume with 5% (vol/vol) acetic acid. This should be stored in a cool, dark place. On the day of the experiment, dilute an aliquot of this 1 10 to obtain a 10-ppm working standard solution. Dilute aliquots of this with 5% acetic acid to prepare standards of 0 (blank), 0.2, 0.4, 0.6, 0.8, and 1.0 ppm riboflavin. 

Mass percent Molarity (M) Standard solution Dilution... 

Fatty acid determination Transfer all remaining saponified solution to a separatory funnel, add 100 mL water and 5 mL HCl, and extract twice with 50-mL portions of ethyl ether. Dilute the combined ether extracts to volume in a 100-mL volumetric flask. Transfer an aliquot to a 10-mL test tube, evaporate to dryness at 40 C, and add BF3-methanol reagent. React at 65°C for 5 min, then transfer to a 50-mL separatory funnel, add 15 mL saturated NaCl solution, and extract with 10 mL ethyl ether. Add 1 mL of 250 ppm n-eicosane internal standard solution, dilute to 10 mL with ether, and analyze by gas chromatography, comparing to ethyl ether solutions of fatty acids (100-500 ppm) derivatized in the same way. GC Conditions 2% DEGS + 0.5% H3PO4 on Chromosorb W (AW-DMCS), 0.3 X 225 cm, 165 C, FID. 

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