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Showing papers on "Buffer solution published in 1974"


Journal ArticleDOI
TL;DR: In this article, it has been observed that the addition of dixanthogen in a nitrogenated solution does not produce any hydrophobicity at the surface of pyrite electrode and does not alter the rest potential and cathodic polarogram.

34 citations


Patent
25 Feb 1974
TL;DR: In this paper, a column packed with a granular support to which a boronic acid was covalently bonded to reversibly complex the enzyme was used to purify serine-hydrolytic enzymes.
Abstract: Soluble serine-hydrolytic enzymes are purified by passing a solution at pH 7.5 through a column packed with a granular support to which is covalently bonded a boronic acid to reversibly complex the enzyme; washing the column with a first buffer solution; freeing the enzyme by washing the column with a second buffer solution; and isolating the freed enzyme.

14 citations


Patent
01 Mar 1974
TL;DR: In this article, an analytic sorbent material is prepared by wetting a particulate inorganic crystalline lattice material, such as magnesium silicate with an aqueous fluid such as a barbital buffer solution or distilled water, and thereafter heating the wetted sorbent until its sorption capacity stabilizes.
Abstract: An analytic sorbent material is prepared by wetting a particulate inorganic crystalline lattice material, such as magnesium silicate with an aqueous fluid such as a barbital buffer solution or distilled water, and thereafter heating the wetted sorbent until its sorption capacity stabilizes.

9 citations


Journal ArticleDOI
TL;DR: In this paper, the authors used water soluble porphyrin, α, β, γ, δ-tetraphenylporphine-trisulfonate (TPPS), for both the direct spectrophotometric determination and the photomeric titration of copper(II).
Abstract: Water soluble porphyrin, α, β, γ, δ-tetraphenylporphine-trisulfonate(TPPS), was found to be very useful agent for both the direct spectrophotometric determination and the photomeric titration of copper(II). The soret bands of TPPS and Cu-TPPS complex at pH 2.5 were at the wavelength of 434 nm (e=5.0×105) and at 413 nm(e=4.76×105), respectively. For the determination of copper, the wavelength of 434 nm was used and the sensitivity of the method was 0.00013 μg Cu2+·cm-2 for A=0.001. Beer's law was followed in the range 060 ng·ml-1. Among twenty-two metal ions examined, only zinc(II) seriously interfered with the determination. The selectivity of the method seems to be largely depend on the kinetic nature of the metal incorporation reaction of TPPS.The recomended procedure is to add 2.5 ml of 1 M acetate buffer solution(pH 4.0) and 5 ml of 1×10-5 M standard TPPS solution to an about 40 ml solution containing 0.33 μg of copper, followed by heating to boil for one minute and by cooling to room temperature, then to adjust pH to 2.5 with 1.5 ml of 1 M chloroacetic acid solution, to dilute to 50 ml and measure the absorbance(A) at 434 nm against water with 1 cm cells. Copper concentration is determined from the decrease in absorbance by complexation as follows: Cu(ng/ml)=130×(A0-A), where A0 is the absorbance of reagent blank.

7 citations


Journal ArticleDOI
TL;DR: In this paper, the coprecipitation behaviors of As(III), (V) and Sb(III) ions onto Fe(III or aluminium hydroxide in both buffer solutions and sea water have been studied.
Abstract: Coprecipitation behaviors of As(III), (V)and Sb(III)ions onto Fe(III)or aluminium hydroxide in both buffer solutions and sea water have been. studied. lt was found that As(V)and Sb(III)ions are quantitatively. coprecipitated on Fe(III)hydroxide from pH 6 to 9, and As(III)from pH 7 to 9. Coprecipitation Qnto aluminium hydroxide was quantitative for As(V)in the pH range from 5 to 9 b qt not for As(III) In sea water, almost he same behaviors in the buffer solution were obgerved for these three ions, except the fact that the coprecipitation of As(III), (V)became quantitative in the alkalione so1ution( pH 10)where the coprecipitation onto Mg hydrQxide took place. As a conclusion, these three ions tend to be removed into the sediment in the, hyd, rosp. here by the, coprecipitation process.

3 citations


Book ChapterDOI
01 Jan 1974
TL;DR: In this article, a colorimetric assay with 6-benzamido-4methoxy-m-toluidine diazonium chloride was performed.
Abstract: Publisher Summary This chapter elaborates on colorimetric assay with 6-benzamido-4-methoxy-m-toluidine diazonium chloride. Use of N 1 -buty-4-methoxy-m-anilamide diazonium salt has the advantage of better linearity of the reaction. All reagents must be A. R. or purest grade available. The 2-oxoglutaric acid, l -aspartic acid and oxaloacetic acid must be 98%–100% pure. The buffer/substrate solution and the control buffer solution are stable for two months at 4°C by adding several drops of chloroform. With values around 25 U/l the standard deviation is 2 U/l. Range with 20 healthy subjects was 4–26 U/l. It is not known whether there are other substances in serum which react with 6-benzamido-4-methoxy-m-toluidine diazonium chloride.

2 citations