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477 results about "Phenolphthalein" patented technology

Phenolphthalein is a chemical compound with the formula C₂₀H₁₄O₄ and is often written as "HIn" or "phph" in shorthand notation. Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions. It belongs to the class of dyes known as phthalein dyes.

Water alkalinity on-line measuring device based on solution image technology and measuring method thereof

The invention relates to a water alkalinity on-line detection device, a water alkalinity on-line measuring device based on solution image technology and a measuring method thereof, and is characterized in that according to the invention, based on the detection of solution image RGB values during the titration of water to be detected by a HCl solution, an image RGB value-titration solution volume measuring curve is plotted, and the water alkalinity of the solution to be detected is calculated according to the titration solution volume corresponding to an inflection point of the image RGB value measuring curve. With computer image processing technology, the invention establishes a mathematical model of solution RGB values with the change of the titration solution volume during titration, determines the titration end point automatically, establishes a color constancy algorithm model based on a neural network algorithm, and thus increases the precision and reliability of alkalinity measurement. With the device of the invention, on-line measurement of phenolphthalein alkalinity and total alkalinity can be performed optionally, and the operation is convenient. The device is applicable to industry of electric power, petroleum, chemical industry, metallurgy, etc.
Owner:NORTHEAST DIANLI UNIVERSITY

Preparation method of triethyl citrate

The invention relates to a preparation method of triethyl citrate. The preparation method is as follows: by deeply studying the preparation process of triethyl citrate, setting a reaction feed ratio; then adding catalyst to perform reflux reaction; then utilizing phenolphthalein as an indicator and sodium hydroxide to perform titration to determine the reaction end point; utilizing weak base to neutralize less acidic materials in the obtained product, and eluting sodium carbonate with purified water; and finally utilizing activated carbon to decolor, thus obtaining the pure triethyl citrate product. Compared with the prior art, the preparation method provided by the invention has the advantages that the reaction end point is strictly controlled, unnecessary side reactions are reduced, thereduction of the product quality and the waste of cost caused by inadequate reaction or too long reaction time can be avoided; by controlling the temperatures of the processing steps, the damages caused by side reactions are reduced as far as possible; by selecting the decoloring mode, an ideal, colorless and transparent liquid product can be obtained; and the product quality is above the national standard: especially the acid value is controlled to be about 0.2 while the acid value of the national standard is 1.0, and the stability of the product when stored for a long time is higher than those of the like products.
Owner:蚌埠丰原涂山制药有限公司

Method for simultaneously detecting seven slimming chemical components which are illegally added to traditional Chinese medicine, health food or cosmetics

The invention relates to a method for simultaneously detecting seven slimming chemical components which are illegally added to traditional Chinese medicine, health food or cosmetics. According to the method, an appropriate mobile phase and a reasonable elution gradient are adopted during liquid-phase separation, so that the slimming components needing to be detected are effectively separated within 12 min, the analysis time of a sample instrument is shortened by 88%, and the work efficiency is greatly increased. Additionally, the advantages of high separation ability of the HPLC (High Performance Liquid Chromatography) technology, high sensitivity and stronger qualitative ability of the mass spectrum and the like are combined, so screening and confirmation can be simultaneously completed during one operation. By using the method disclosed by the invention, the seven chemical components including sibutramine, fenfluramine, phenolphthalein, ephedrine, caffeine, N,N-bi-demethylation sibutramine and furosemide can be effectively separated, the inspection time can be shortened, and the slimming chemical components which are illegally added to the traditional Chinese medicine, the health food or the cosmetics can be accurately and effectively distinguished.
Owner:HUNAN INST FOR FOOD & DRUG CONTROL

Carboxyl-side-group-containing polyarylether copolymers and preparation method thereof, and application of copolymers in aspect of ultrafiltration membrane hydrophilic modification

The invention relates to carboxyl-side-group-containing polyarylether copolymers and a preparation method thereof, and application of the copolymers in the aspect of ultrafiltration membrane hydrophilic modification, belonging to the technical field of ultrafiltration membrane preparation. By adopting nucleophilic polycondensation and one-step feeding, the mole ratio of the phenolphthalin bisphenol monomer to the total bisphenol monomer is changed to prepare a series of polyarylether copolymers with different carboxylation degrees; and the polyarylether copolymers are used as the membrane material preparation membrane casting solution to prepare a series of ultrafiltration membranes by an impregnation precipitated-phase conversion process. The hydrophilicity and water flux of the carboxyl-side-group-containing modified polyarylether ultrafiltration membranes are obviously enhanced. The modified monomer phenolphthalin can be obtained only by hydrolyzing/reducing phenolphthalein, so the experimental operation is simple, and the raw material price is low. In addition, the technique has the advantages of enduring chemical hydrophilic modification, high repetitiveness and the like, and is easy to operate.
Owner:JILIN UNIV

Allochroic solid adhesive and preparation method thereof

The invention discloses a high-stability allochroic solid adhesive and a preparation method thereof. The allochroic solid adhesive is prepared by the method according to the following steps: adding all the following raw materials in portion by weight into a reaction kettle of which the temperature is between 50 and 100 DEG C: 50 to 75 portions of dispersant water, 10 to 45 portions of bonding agent such as polyvinyl pyrrolidone, 5 to 18 portions of excipient such as sodium stearate, 5 to 15 portions of humectant such as glycerol, 0.1 to 1 portion of developer phenolphthalein, and proper amount of color stabilizer; stirring the raw materials at a temperature of between 80 and 100 DEG C for one hour, and then adjusting the pH to between 9 and 11; and then standing the mixture at a constant temperature, and bottling the mixture to obtain a purple solid adhesive. The allochroic solid adhesive has a reasonable and simple formulation, easy manufacture and production and low cost; the colloid is purple when the allochroic solid adhesive is coated on a substrate material, and the purple disappears in a short time to meet the requirements in specific fields; besides, the allochroic solid adhesive has the most prominent characteristic that the color is stable during storage and is basically unchanged for more than two years.
Owner:NINGBO SONGHE STATIONERY

Phenolphthalein polyether sulfone containing tertiary amine side group and preparation method thereof

The invention discloses a preparation method of phenolphthalein polyether sulfone containing a tertiary amine side group, which comprises the following steps of: (a) adding a halogenated organic matter monomer or a nitrified organic matter monomer, a catalyst and a solvent into a prepared phenolphthalein bisphenol monomer containing the tertiary amine side group to form a mixed solution; and (b) leading the mixed solution to react at 80-220 DEG C. The invention also discloses a phenolphthalein polyether sulfone homopolymer containing the tertiary amine side group and a phenolphthalein polyether sulfone copolymer containing the tertiary amine side group. The phenolphthalein or the phenolphthalein polyether sulfone is adopted as a raw material to generate substitution reaction with asymmetric amine to obtain the phenolphthalein polyether sulfone containing the tertiary amine side group. Because a tertiary amine group is a polar group and has higher hydrophily, the application limitation of the phenolphthalein polyether sulfone is overcome, and particularly, the adverse effect of the phenolphthalein polyether sulfone used as an ultrafiltration membrane or a reverse osmosis support base membrane applied to water treatment is eliminated. Meanwhile, the tertiary amine group has higher activity, is easy to convert into other groups, such as a quaternary amine group, and the like, and is beneficial to the further functionalization of the phenolphthalein polyether sulfone and the modification of a polyether sulfone product.
Owner:CHANGCHUN INST OF APPLIED CHEMISTRY - CHINESE ACAD OF SCI

Quaternary ammonium lateral group-containing phenolphthalein type polyarylether, copolymer thereof and method for preparing same

The invention provides quaternary ammonium lateral groups-containing phenolphthalein type polyarylether and the method for preparing the same. The preparation method comprises the following steps of: dissolving a bisphenol monomer and a di-halogen monomer of tertiary amine lateral groups-containing phenolphthalein, which serve as raw materials, into an aprotic polar solvent to perform a reaction to obtain the tertiary amine lateral groups containing polyarylether; and after the reaction is ended, dissolving the obtained tertiary amine lateral groups-containing polyarylether in the aprotic polar solvent to perform a reaction with halogenated hydrocarbons. The preparation method can accurately control the positions and number of the quaternary ammonium functional groups, avoids the use of chloromethylation reagent(such as methylchloromethyl ether) which is highly poisonous and a strong carcinogen; and the obtained quaternary ammonium lateral groups containing phenolphthalein type polyarylether has good dissolvability and contributes to the further functionalized application; and the tertiary amine groups contained in the intermediate product of the tertiary amine lateral group-containing polyarylether easily make other similar reactions so as to derive other functional groups.
Owner:CHANGZHOU INST OF ENERGY STORAGE MATERIALS &DEVICES

Highly sensitive pH test paper and preparation method thereof

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.
Owner:上海馨晟试化工科技有限公司

Method and device for continuously analyzing pH value, phenolphthalein end-point alkalinity, total alkalinity and chloridion concentration

The invention discloses a device and a method for continuously analyzing pH value, phenolphthalein end-point alkalinity, total alkalinity and chloridion concentration. The method comprises the following steps: a. using a standard acid liquid adding unit to perform alkalinity titration to a sample to be detected, and sequentially performing the alkalinity titration: phenolphthalein end-point alkalinity titration and total alkalinity titration, and respectively reading corresponding liquid volume values for titration in the titration end-point, calculating the phenolphthalein end-point alkalinity and the total alkalinity, wherein the initial pH value acquired by a pH electrode is the pH value of the sample to be detected; and b. performing chloridion potentiometric titration to the sample to be detected after the total alkalinity is completed, reading the liquid volume value for the titration when in the titration end-point and calculating the chloridion concentration. The device for continuously analyzing the pH value, the phenolphthalein end-point alkalinity, the total alkalinity and the chloridion concentration comprises a potentiometric titrimeter main machine with double electrode interfaces, the pH electrode (1), the standard acid liquid adding unit (2), a silver electrode (3), a silver nitrate standard liquid adding unit (4) and a control system. According to the invention, the detection time is greatly shortened, the working efficiency of the device is improved, and the sample consumption and the standard acid liquid consumption are saved.
Owner:SHENZHEN INST OF SPECIAL EQUIP INSPECTION & TEST

Method for preparing sodium carboxymethylcellulose by abandoned cotton fabrics

The invention discloses a method for preparing sodium carboxymethylcellulose by abandoned cotton fabrics, which includes cleaning, drying and cutting up the abandoned cotton fabrics, placing the abandoned cotton fabrics into a pretreating agent solution for heating and stirring, and filtering out after the abandoned cotton fabrics faded; placing and heating the abandoned cotton fabrics in a sodium hydroxide solution for 45-90 minutes at the temperature from 75 DEG C to 100DEG C until colors of the abandoned cotton fabrics are completely faded, and obtaining celluloses; submerging the celluloses into the sodium hydroxide solution, heating the celluloses for 1.5-2 hours at the temperature from 30 DEG C to 50 DEG C, and then removing the sodium hydroxide solution to obtain alkali celluloses; shredding the alkali celluloses and adding absolute ethyl alcohol and the sodium hydroxide solution; dropwise adding a chloroacetic acid ethanol solution at the temperature from 50 DEG C to 60 DEG C; heating for 80-100 minutes at the temperature from 70 DEG C to 80 DEG C; performing a suction filtration and washing; and adding a phenolphthalein indicator, dropwise adding hydrochloric acid for a neutralization until the solution is colorless, washing 1-2 times, and drying after a suction filtration to obtain a finished product.
Owner:CHANGAN UNIV

Method for determining content of calcium fluoride in fluorite

The invention relates to a method for determining the content of calcium fluoride in fluorite. The method comprises the steps that 1, a calcium-containing acetic acid solution with the calcium content ranging from 0.8 mg/mL to 2.0 mg/mL is prepared; 2, a fluorine-containing washing solution with the fluorine content ranging from 10 micrograms per milliliter to 20 micrograms per milliliter; 3, a fluorit sample is soaked with the calcium-containing acetic acid solution, then filtering is performed with low-speed filter paper, a beaker and precipitate are washed with the fluorine-containing washing solution, the low-speed filter paper and the precipitate are placed in a muffle furnace to be incinerated and burnt, a mixed solution of sodium carbonate and boric acid is added after the low-speed filter paper and the precipitate are cooled, the mixture is put in a high-temperature furnace to be fused and then put in a hydrochloric acid solution, a saturated boric acid solution is added for leaching, and the liquid is diluted with water to obtain a test solution after being cooled; 4, a magnesium sulfate solution, water, a triethanolamine solution, a mixed solution of sodium sulfide and hydroxylamine hydrochloride and a potassium hydroxide solution are added in the test solution, the mixture is shaken evenly, a calcein-thyme mixed phenolphthalein indicator is added, the mixed solution is titrated with an EDTA standard titration solution until the mixed solution turns into prunosus, and then the content of the calcium fluoride is calculated according to the volume number of the standard titration solution.
Owner:武汉钢铁有限公司
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