Apparatus for determining an amount of halide in a drilling fluid and methods of use. An example apparatus utilizes an analyzer configured to determine an amount of a halide precipitate in a substantially solids-free sample of a drilling fluid by measuring the amount of the precipitated halide produced upon contacting the substantially solids-free sample of drilling fluid with a cation. A solids removal device is configured to prepare the substantially solids-free sample by removing solids from a sample of the drilling fluid to produce the substantially solids-free sample fluid.

Apparatus for determining an amount of halide in a drilling fluid and methods of use. An example apparatus utilizes an analyzer configured to determine an amount of a halide precipitate in a substantially solids-free sample of a drilling fluid by measuring the amount of the precipitated halide produced upon contacting the substantially solids-free sample of drilling fluid with a cation. A solids removal device is configured to prepare the substantially solids-free sample by removing solids from a sample of the drilling fluid to produce the substantially solids-free sample fluid.

A method of extracting calcium ions from soil including: mixing soil with a solvent to produce a soil slurry; mixing the soil slurry with ammonium acetate to produce an extracted sample; filtering the extracted sample to produce a first filtrate; mixing the first filtrate with a precipitation reagent to produce precipitated calcium oxalate and a liquid solution; and separating the calcium oxalate from the liquid solution; wherein the precipitation reagent comprises from about 0.15 to about 0.35 M of an oxalate salt dissolved in a buffer having a pH from about 7.1 or more. Also, a system and a kit using the method.

A method of extracting calcium ions from soil including: mixing soil with a solvent to produce a soil slurry; mixing the soil slurry with ammonium acetate to produce an extracted sample; filtering the extracted sample to produce a first filtrate; mixing the first filtrate with a precipitation reagent to produce precipitated calcium oxalate and a liquid solution; and separating the calcium oxalate from the liquid solution; wherein the precipitation reagent comprises from about 0.15 to about 0.35 M of an oxalate salt dissolved in a buffer having a pH from about 7.1 or more. Also, a system and a kit using the method.

An method for detecting a target substance includes providing a sample including the target substance and an active species, converting the active species into a deactivated species, adding a reactive agent into the sample to form a solid species including the target substance, separating the solid species from the deactivated species by solid-liquid separation, and determining a concentration of the target substance in the sample by measuring a concentration of the target substance in the solid species.

An method for detecting a target substance includes providing a sample including the target substance and an active species, converting the active species into a deactivated species, adding a reactive agent into the sample to form a solid species including the target substance, separating the solid species from the deactivated species by solid-liquid separation, and determining a concentration of the target substance in the sample by measuring a concentration of the target substance in the solid species.

A process for quantifying the amount of unbound metal and bound metal in solution is provided. A process for quantifying the amount of bound metal amino acid chelate and free ligand in a solid (e.g., dry mixture such as an animal feed) is also provided.

A process for quantifying the amount of unbound metal and bound metal in solution is provided. A process for quantifying the amount of bound metal amino acid chelate and free ligand in a solid (e.g., dry mixture such as an animal feed) is also provided.