36 results about "Cresol Red" patented technology

In lithography, a composition comprising a novolak resin comprising recurring units derived from a phenolphthalein, Phenol Red, Cresolphthalein, Cresol Red, or Thymolphthalein is used to form a photoresist underlayer film. The underlayer film is strippable in alkaline water, without causing damage to ion-implanted Si substrates or SiO2 substrates.

The invention relates to a piece of highly sensitive pH test paper and a preparation method thereof, wherein a developing strip is in the form of a piece of pH body paper, which is dipped in a reagent solution and then dried by hot air at constant temperature; the reagent solution contains an indicator; the formula of the indicator contains bromothymol blue, thymol blue, metanil yellow, m-methyl red, bromocresol green, nitrazine yellow, cresol red, phenolphthalein, para-nitrophenylazosalicylate sodium, titan yellow, fluorescent pigment orange red, 5% 4-nitrobenzenediazo-1-naphthol-3.6-sodium disulfonate solution and 30% dissolved ethanol aqueous solution; and the formula of the indicator further contains an aqueous colour fixing agent, a cotton wooden fibre mildew preventive, a special paper mildew preventive and a buffer neutralizer formed by modulating sodium hydroxide and phosphoric acid. The preparation method comprises the following steps of: adjusting the reagent solution till a pH value is up to 6-7.5, uniformly wetting the pH body paper, and drying through hot air at constant temperature. According to the invention, the reagent solution can be adjusted, so that the pH value is up to 6-7.5; steady and precise high sensitivity of the pH1-14 test paper is effectively increased; and the test paper is convenient and simple to use.

The invention relates to a novel PCR (Polymerase Chain Reaction) reaction method belonging to the field of biochemistry and molecular biology. The novel PCR reaction method sequentially comprises the following steps of: (1) preparing a compatible dye mixture, wherein the compatible dye mixture comprises ficoll 400, cresol red, lemon yellow and Gelred; (2) preparing a PCR principal mixture, wherein the PCR principal mixture comprises the compatible dye mixture, dNTP (Deoxy-ribonucleoside Triphosphate), a Taq DNA polymerase and a reaction buffer solution; (3) configuring a PCR reaction system; (4) setting and operating PCR reaction conditions; and (5) detecting PCR products. The novel PCR reaction method realizes the direct point sample electrophoresis and the immediate dyeing after PCR reaction; besides, the novel PCR reaction method uses a nontoxic nucleic acid dye and has low cost and high efficiency without toxicity; the obtained PCR products can be used for directly carrying out multiple downstream operations, such as ethanol precipitation, silica gel membrane product purification, and the like; and in addition, the novel PCR reaction method is suitable for the research of geneexpression detection related to PCR, gene clone, and other aspects.

The invention relates to a preparation method of accurate pH test paper. An indicator is prepared by dissolving Metanil yellow, malachite green, acid turquoise blue, bromphenol blue, cresol red, m-cresol purple and bromocresol green in a 30% ethanol water solution. The preparation method comprises the following steps: previously impregnating base paper of pH test paper in the prepared indicator solution, and drying with heating steam of 95-105 DEG C at normal pressure. The preparation method of accurate pH test paper is simple in process, stable in product quality and higher in sensitivity and accuracy in comparison with the common accurate test paper, and the accuracy can be up to 0.2 level. Thus, the preparation method can be widely used in the fields of scientific research, industry, agriculture, environmental protection, medicine and food.

The invention discloses a method for determining the content of yeast selenium total selenium, inorganic selenium and organic selenium. After the sample is heated and digested by acid, the selenium in the sample is uniformly reduced to tetravalent selenium in the hydrochloric acid medium, and the tetravalent selenium reacts with 2,3-diaminonaphthalene (DAN) under slightly acidic conditions to form kohlrabi selenium. , extracted with cyclohexane. Fluorescence intensity was measured with a fluorescence photometer to calculate the selenium content in the sample. The determination of total selenium uses 3 mL mixed acid, which greatly reduces the amount of mixed acid; digestion and extraction are carried out in a water bath in a capped round bottom flask, which can avoid the pollution of the laboratory environment by strong redox acid, and can also Prevent the volatilization loss of selenium and obtain a higher recovery rate; cancel the use of cresyl red indicator, avoid the interference of the sample on the judgment of the color change of the indicator, and also reduce the interference of the indicator to the liquid to be tested. The determination time of total selenium and inorganic selenium is greatly shortened, and the digestion of total selenium and the extraction of inorganic selenium can be completed in about one hour at the same time.