10 results about "Bromothymol blue" patented technology

The invention discloses a method for detecting the content of free carbon in a tungsten-titanium solid solution, and belongs to the field of analytical chemistry. According to the method, based on the adsorption effect of the free carbon on bromothymol blue, an adsorption reaction is carried out in an acidic buffer system, and selective adsorption of the free carbon is realized; and then carrying out solid-liquid separation, alkalifying the filtrate, measuring the absorbance under the wavelength of 574nm, and calculating the content of free carbon by using a standard curve method according to the absorbance difference. The method has the advantages of simplicity and convenience in operation, low cost, no use of strong corrosive acid, environmental friendliness and the like. Compared with a high-frequency infrared method, the precision is remarkably improved, and the method is suitable for rapid and accurate determination of free carbon in the tungsten-titanium solid solution.

The application belongs to the field of chemical detection and analysis, and particularly relates to a method for analyzing potassium hydroxide in a hydrazine boronic acid system, comprising the following steps: step 1, adding hydrogen peroxide to a sample for sample pretreatment; step 2, adding bromothymol blue indicator to the pretreated sample, titrating the pretreated sample with hydrochloric acid, and recording the volume of hydrochloric acid consumed by the sample; step 3, performing a blank test, and recording the volume of hydrochloric acid consumed by the blank test; step 4, calculating the concentration of KOH in the sample, denoted as a measured concentration; and step 5, calculating the difference of the measured concentration, and determining the concentration of KOH in the sample. The method can solve the interference of a weak acid and weak base system on the titration of potassium hydroxide, and can quickly and accurately analyze the concentration of potassium hydroxide in a potassium hydrazine boronic acid alkali solution by adding hydrogen peroxide for pretreatment and selecting bromothymol blue as an indicator.

The present invention provides a cleaning composition containing alkaline electrolyzed water, which facilitates the production of a diluted solution having a predetermined pH. [Solution] A cleaning composition is provided which contains bromothymol blue, thymol blue, or phenolphthalein as a pH indicator, and alkaline electrolyzed water having a pH of 12 or higher.

The invention relates to the technical field of automobile wire harness sheath quality inspection, in particular to an automobile wire harness sheath sealing detection device and method.The automobile wire harness sheath sealing detection device is characterized in that an anti-explosion glass water tank is fixedly installed on a machine body, and a sealing detection part conveys carbon dioxide gas into a wire harness sheath immersed in a sodium hydroxide solution through a first gas supply pipe; whether bubbles exist in the sodium hydroxide solution and whether the sodium hydroxide solution changes from blue to yellow are observed, and if yes, the carbon dioxide gas in the wire harness sheath leaks. An explosion-proof glass water tank for dissolving a sodium hydroxide solution of bromothymol blue is arranged, a lifting frame capable of vertically lifting is arranged on an oscillation moving frame, then air is conveyed into a wire harness sheath through a second air supply pipe, and after the sodium hydroxide solution is heated, whether the sodium hydroxide solution changes from yellow to blue or not is observed, so that secondary judgment is carried out; meanwhile, the sodium hydroxide solution for detection is subjected to convenient and efficient state recovery, so that the sodium hydroxide solution can be reused conveniently.

According to the pH detection cat litter based on the plant particles and the preparation method of the pH detection cat litter based on the plant particles, the plant starch particles with the neutral pH are selected as inner cores, and interference of traditional mineral matrix alkalinity deviation on the detection accuracy is effectively avoided; in combination with a polymer coating fixed bromothymol blue and methyl red double indicator system, by utilizing the complementary characteristic of color change intervals of bromothymol blue and methyl red, the obvious color change from orange red to green is realized at the critical threshold of cat urine pH 6.8-7.0, and the problems of blurred color development and difficulty in identifying a transition region in the prior art are solved. Meanwhile, the storage stability and the liquid response speed of the indicator are effectively improved.

The method comprises the following steps: dissolving a to-be-detected sample with water or extracting with water to obtain a to-be-detected water sample, mixing the to-be-detected water sample with a boric acid buffer solution with the pH value of 8-9 and a bromothymol blue solution, adding dichloromethane into an obtained water phase solution, mixing, standing for layering, observing the color change of a dichloromethane layer, and carrying out qualitative analysis or quantitative analysis. According to the method, a detection system for developing after organic solvent extraction is provided for the first time, the detection sensitivity is high, the response time is short, the specificity is good, interference of common cations can be eliminated, and the method is rapid, sensitive, simple and convenient, can be used for short-chain quaternary ammonium salt detection and has high practical value.

This invention discloses the preparation and application of an integrated antibacterial hydrogel dressing for diagnosis and treatment. The preparation method of the integrated antibacterial hydrogel dressing includes: mixing a polyvinyl alcohol solution and a sodium alginate solution to prepare a spinning solution; adding gold nanoparticles; and then using wet spinning technology to obtain hydrogel fibers, which are woven into a dressing. After freeze-drying, the dressing is immersed in a bromothymol blue solution and then vacuum dried to obtain the dressing. In the dressing, bromothymol blue can achieve real-time visual detection of bacterial infection by sensing changes in the pH of the wound; the gold nanoparticles, with their unique bipyramidal needle-like structure and excellent photothermal properties, exhibit highly efficient antibacterial activity with or without laser assistance; and wet spinning imparts high porosity and excellent water vapor permeability to the dressing, providing a suitable microenvironment for wound healing.

The invention belongs to the field of chemical detection, and particularly relates to a method for determining silicon dioxide in a quartz flux for copper smelting. The method specifically comprises the following steps: leaching with hot water, acidifying, adding potassium chloride, potassium fluoride and silicate into a strong acid solution to form potassium fluosilicate precipitate, hydrolyzing the potassium fluosilicate in the hot water, separating out hydrofluoric acid with equal amount of substance, and titrating with a sodium hydroxide standard titration solution by taking phenol red-bromothymol blue as an indicator, and calculating the mass fraction of silicon dioxide according to the volume of the consumed sodium hydroxide standard titration solution. According to the method, acid-base titration is adopted, and the process is short (3.5 hours). The method is a simple, convenient, rapid and low-cost chemical analysis method; and the detection range is 0.50%-99.9%.

This invention relates to a portable kit for rapid detection of microbial contamination of water, which includes two vials containing lactose broth culture medium and bromothymol blue color indicator, a dropper for sample collection, and an activatable heating pad. The main innovation of this invention is the use of an insulated box covered with a foil layer and, together with the heating pad, acting as an independent incubator. The vials are fixed inside a cylindrical foam and the sample, after addition, is placed at the appropriate growth temperature without the need for an incubator. This system allows for rapid and field detection of water-polluting bacteria, especially coliforms and Escherichia coli.