Showing papers on "Color reaction published in 2020"
TL;DR: In this article, the hierarchical porous carbon (DHPC) was prepared by treating DMC with potassium hydroxide, and the DHPC was loaded on chitosan to prepare DHPC@CS, which was then doped into nanosilver via the one-pot process to prepare Hg2+AgNPs.
9 citations
TL;DR: In this paper, a combination of magnetic solid phase extraction with a designed portable photometer based on light-emitting diodes is suggested for on-site determination of trace amount of nitrite in atmospheric liquids and surface water.
5 citations
TL;DR: In this article, a color reaction of phenols with diazotized 4-nitroaniline and micellar extraction of the products of their interaction (azo compound) was used for the determination of phenol and resorcinol at the MPC level.
Abstract: We studied the extraction and preconcentration of phenol and its hydroxy derivatives using individual and mixed micelles of nonionic and cationic surfactants with the digital recording of the analytical signal. This approach is based on the color reaction of phenols with diazotized 4-nitroaniline and micellar extraction of the products of their interaction (azo compound). The micellar extraction parameters (pH, the concentration of reagents, NaOH, and ethanol) were optimized for the efficient extraction of azo compounds of the studied phenols. The proposed method enables the determination of phenol and resorcinol at the MPC level with an error not exceeding 10%. For a qualitative assessment of the presence of phenols, the geometric parameters (area S, perimeter P) of the corresponding radar plots were used along with colorimetric parameters (R, G, B). The calibration dependences are linear within 1 × 10–7–3 × 10–5 M for phenol and 1 × 10–7–2 × 10–5 M for resorcinol and phloroglucinol. The developed colorimetric method was tested in the determination of resorcinol in the Rezortsinol pharmaceutical preparation.
1 citations
Patent•
21 Feb 2020
TL;DR: In this paper, the total iron content in a solution is determined at the maximum absorption wavelength 710nm in the range of 475 to 800nm by using an ultraviolet and visible spectrophotometer with a blank control solution.
Abstract: The invention proposes a method for determining total iron in a solution When the total iron content in a solution is detected by using an ultraviolet-visible spectrum, a buffering agent acetic acid-sodium acetate solution is firstly added to the solution to adjust a pH value of the solution, then a steady adjuvant solution is added into the solution, a hexadecyl trimethyl ammonium bromide (CTMAB) solution is added to a solution to be tested, and finally, color developing agent nitroso R salt is added, so that the color developing agent nitroso R salt is in complexation color reaction with ferreous and ferric iron in the solution, and distilled water is added to a 25ml test tube and shaken well The total iron content is determined at the maximum absorption wavelength 710nm in the range of 475 to 800nm by using an ultraviolet and visible spectrophotometer with a blank control solution as a reference The method has simple steps and convenient operation, and can quickly and efficientlymeasure the total iron content in the solution
1 citations
TL;DR: An improved phosphorous determination was developed using ethanol, phosphorus determination reagent (PDR) and Ultraviolet-visible spectroscopy (UV-Vis) for analyzing the bisphosphonates (BPs) and could be a new method to measure the drug content of BPs.
1 citations
Patent•
01 Sep 2020
TL;DR: In this paper, a color gas sensing chip consisting of a chemical reaction layer and a reaction coloring layer arranged in a stack is presented. But it is not suitable for real-time sensing.
Abstract: The invention relates to a color gas sensing chip comprising a chemical reaction layer and a reaction coloring layer arranged in a stack. The chemical reaction layer comprises a reaction zone which is able to react with gas to be tested to generate an chemical reaction; while the reaction color layer comprises a coloring surface and a reaction surface corresponding to the coloring surface and in contact with the reaction zone. The reaction coloring layer further comprises an indicator to generate a color reaction corresponding to said chemical reaction, thereby completing a light and highly integrated gas sensing chip. The color gas sensing chip of the invention can be attached or placed on the sensing object for real-time sensing.