32 results about "Chromotropic acid" patented technology

The present invention discloses a method for testing hydroxypropylmethyl cellulose methyl substitution degree. The reaction step comprises 1, oxidation of a hydroxypropylmethyl cellulose solution and a potassium permanganate solution is performed in the presence of sulfuric acid and phosphoric acid at -5 to 0 DEG C; 2, a reaction liquid obtained by the step 1 and sodium bisulfate are mixed, added with concentrated sulfuric acid and a discoloration acid solution while shaking, and reacted at 55 ~ 65 DEG C, wherein the discoloration acid is 1,8- dihydroxy naphthlene -3,6- disulfonic acid; and 3, the reaction liquid obtained in the step 2 is diluted to 0.3 time to 0.8 time of the original solution concentration, and the absorbance at 570nm wavelength of the solution is tested. The test method is low in instrument requirement, high in sensitivity, high in accuracy, simple in operation, and low in cost, can quickly and efficiently determine hydroxypropylmethyl cellulose methyl substitution degree, and has a good market prospect.

The invention provides a method for detecting non-protein nitrogen-containing compounds in a feed protein raw material. Compared with other aldehyde, ketone and carbohydrate, formaldehyde produced in the decomposition of an ureaformaldehyde polymer, which is one of the non-protein nitrogen-containing compounds (NPN), under the action of hot sulfuric acid, has the characteristic that formaldehyde can form a purplish red substance with chromotropic acid, and the characteristic can be utilized for verifying whether the raw material is adulterated. The method comprises the following steps: after degreasing and drying the protein raw material with petroleum ether, placing the sample under a stereo microscope; picking out and placing suspicious materials into a 50ml beaker with a pair of tweezers; adding 1ml of chromotropic acid into the beaker; heating the beaker with an electric stove until fume starts rising; and taking the beaker off from the electric stove, and adding 50ml of water into the beaker instantly. The fact that the liquid turns purplish red shows that a non-protein nitrogen (NPN)-containing compound, called unreaformaldehyde polymer, is present in the sample, so that whether the sample is adulterated can be verified accurately.

The invention relates to a process utilizing H acid mother liquor to recover and produce chromotropic acid sodium salt, belonging to the technical field of organic chemistry. The process comprises the following steps of utilizing the H acid mother liquor for extracting and concentrating and separating organic matters; and adding sulfuric acid and hot water into a high-pressure hydrolyzing reactor for high-pressure hydrolyzing, then carrying out segregation, suction filtration, washing and drying, and finally obtaining a chromotropic acid sodium salt finished-product. With the adoption of the process, the organic components in the H acid mother liquor are recovered, the multiple components are successfully changed into single-component chromotropic acid through a chemical process, and the color spectrum and the chemical content are more than 96 percent. The extract liquor of the H acid mother liquor in the prior art cannot be recovered, and the organic matters can be processed only through high-temperature incineration. Compared with the prior art, the method has the advantages that the wastewater treatment cost is reduced, the abandoned pollutants are recycled, and the benefit is created.

The invention discloses a method for detecting the content of methanol in transformer insulation paper, and the method comprises the following steps of: S1, adding 1mL of to-be-detected methanol into a 25mL colorimetric tube, sequentially transferring 2.5mL of a 25% sulfuric acid solution and 0.5mL of a potassium permanganate solution, uniformly shaking and standing the substances for 10min to obtain a first mixed solution; S2, dropwise adding a sodium sulfite solution into the first mixed solution obtained in the S1 until the color just fades, then dropwise adding two drops of chromotropic acid, uniformly mixing the substances, slowly transferring 6mL of concentrated sulfuric acid along the wall of a colorimetric tube, and uniformly mixing the substances; S3, performing standing and cooling to room temperature, adding water to dilute to a 25mL scale line, and uniformly mixing the substances to obtain a to-be-detected mixed solution; and S4, measuring 3mL of the to-be-detected mixed solution, putting the solution into a 10*10mm quartz cuvette, taking pure water as a reference solution, detecting the absorbance of the mixed solution by using a spectrograph, recording the spectrum of the mixed solution, and calculating the methanol concentration. Based on the spectrum principle, the methanol concentration is obtained according to the relation between the methanol concentration and the characteristic absorbance, the detection cost is reduced, and the detection accuracy is improved.

The invention discloses a method for determining the total alkali content of cephalotaxus alkaloids in a cephalotaxaceae plant. The method comprises the following steps that 1, a standard cephalotaxus alkaloid product is selected, a chromotropic acid solution, strong phosphoric acid and hydrogen peroxide are added, even shaking is performed, and then microwave heating is performed to obtain a standard production reaction solution; 2, the standard production reaction solution is cooled to reach room temperature, volume setting and color comparison are performed, a light absorption value obtained through color comparison is associated with the concentration of the standard cephalotaxus alkaloid solution in the step 1, and a standard light absorption value-concentration curve of the cephalotaxus alkaloids is established; 3, suspension culture cells of a cephalotaxaceae plant sample or the cephalotaxaceae plant are selected, and the total alkali of the cephalotaxus alkaloids of the cells is extracted; 4, the light absorption value is measured by referencing the steps 2 and 3, the measured light absorption value is substituted into the standard light absorption value-concentration curve to obtain the concentration of the cephalotaxaceae plant sample, and the total alkali content of the cephalotaxus alkaloids in the cephalotaxaceae plant sample is obtained through conversion. The method is simple, convenient, safe, quick and accurate.

The invention provides a method for detecting methanol in light petroleum; the method comprises the following steps: step one, taking 80-120 parts by volume of the light petroleum, and adding 8-12 parts by volume of distilled water; step two, taking 0.8-1.2 parts by volume of an aqueous phase, adding 1-2 parts by volume of a potassium permanganate aqueous solution, mixing evenly, heating until the solution has a brick-red turbid matter appearing, adding 1-2 parts by volume of an oxalic acid aqueous solution, and oscillating until the solution is transparent and bright red; step three, adding 0.8-1.2 parts by volume of a chromotropic acid aqueous solution into the solution obtained in the step two, stirring until the solution is light yellow, then adding 1.5-2.5 parts by volume of concentrated sulfuric acid, if the solution is observed to be purple blue, indicating that the content of methanol in the light petroleum is higher than 0.5%, and if the solution is still light yellow, indicating that the light petroleum does not contain methanol or the content of methanol in the light petroleum is less than 0.5%. The method can realize fast, simple, inexpensive and on-site detection of methanol in the light petroleum.

The invention discloses a method for combinedly determining contents of chromium, nickel and titanium in high-chromium nickel stainless steel. The method comprises the following steps of: (1) preparing a solution, placing stainless steel in a bottle, adding chloroazotic acid into the bottle to dissolve the stainless steel, adding perchloric acid, smoking, cooling, and diluting into constant volume to obtain the solution; (2) determining the content of the chromium: determining the absorbance value of chromium; (3) determining the content of the nickel: placing the partial solution into a volumetric flask, adding a potassium sodium tartrate masking agent, ammonium persulfate and dimethylglyoxime sequentially for color development, and determining the absorbance value of nickel; and (4) determining the content of the titanium: placing one part of solution into the volumetric flask, adding ascorbic acid and chromotropic acid in certain concentration for color development, and determiningthe absorbance value of the titanium in the reference of titanium free stainless steel. The method has the advantages of: high accuracy, high repeatability, short determination system time, low determination cost and the like.

The invention discloses a method for determining the total alkali content of cephalotaxus alkaloids in a cephalotaxaceae plant. The method comprises the following steps that 1, a standard cephalotaxus alkaloid product is selected, a chromotropic acid solution, strong phosphoric acid and hydrogen peroxide are added, even shaking is performed, and then microwave heating is performed to obtain a standard production reaction solution; 2, the standard production reaction solution is cooled to reach room temperature, volume setting and color comparison are performed, a light absorption value obtained through color comparison is associated with the concentration of the standard cephalotaxus alkaloid solution in the step 1, and a standard light absorption value-concentration curve of the cephalotaxus alkaloids is established; 3, suspension culture cells of a cephalotaxaceae plant sample or the cephalotaxaceae plant are selected, and the total alkali of the cephalotaxus alkaloids of the cells is extracted; 4, the light absorption value is measured by referencing the steps 2 and 3, the measured light absorption value is substituted into the standard light absorption value-concentration curve to obtain the concentration of the cephalotaxaceae plant sample, and the total alkali content of the cephalotaxus alkaloids in the cephalotaxaceae plant sample is obtained through conversion. The method is simple, convenient, safe, quick and accurate.

The invention discloses a titanium content measuring method of copper alloys, which comprises the following steps: A. a copper alloy sample is weighed and dissolved; B. a solution that is obtained from step A is added into an ascorbic acid solution, pH value of the solution is adjusted between 1.5 and 2.5, and a chromotropic acid solution is further added; C. the solution that is obtained from step B is partly poured into a cuvette and taken as a visualization reagent, a complex compound formed by the titanium and the chromotropic acid is removed from the residue solution, and the residue solution is taken as a reference liquid; and D. a photometer is used for simultaneously measuring the visualization reagent and the reference liquid, absorbency values are measured and read, and the titanium content in the copper alloy is computed according to the absorbency values. The titanium content measuring method of the copper alloys has the advantages of stable color development, good result repeatability, high accuracy and wide measurement range.

The invention relates to a pollution-free preparation process of a direct blue 281 dye. The process comprises the following steps: firstly, dissolving a red base B and OP-10, subsequently adding sodium nitrite for diazotization, further coupling the diazotized red bases B with chromotropic acid at 0-10 DEG C when the pH value is 8.5, and reducing a coupled product by using a glucose solution for coupling, wherein the temperature t is 50-60 DEG C and the pH value is 12.5-13; finally performing spray drying to obtain a finished dye product. Due to the added OP-10 which can be used for remarkably increasing the dissolution speed of the red base B when the red base B is dissolved, the pulping time is effectively shortened, i.e., the time is reduced to be 2 hours from 4 hours, the temperature of the melting point of OP-10 is 68-78 DEG C, the hydroxyl value is 87+5, and because of the unique physical and chemical characteristics, the dispersion velocity of the red base B is remarkably increased, the dispersion efficiency is improved, the whole production time is further shortened, the production efficiency is improved, and the capacity is increased.

This invention discloses a kit that can distinguish brewed vinegar and blended vinegar. It includes box, there are standard color plate, color comparison tube, trickle irrigator, reagent bottle A, B and C. Reagent in A is acidic potassium permanganate aqueous solution of mass percent concentration 1-3%. PH value of the acidic permanganate aqueous solution is 1.5-4.0. Reagent in B is sodium bisulphate aqueous solution of concentration is 5-10%. Reagent in C is chromotropic acid sulfuric acid aqueous solution of concentration is 2-5%, the concentration of sulfuric acid aqueous solution is 0.02-0.05 mol / L. all kinds of vinegars in commodities circulation fields and vinegar generating enterprise can be quickly and accurately detected by this method. Its operation is simple, cost is low, and unprofessional man can also use it to make spot detecting.

Disclosed is a pH-regulated method for preparing a silver nano-cluster with a strong fluorescence emission function. According to the method, chromotropic acid 2R dye serves as a stabilizing agent, sodium borohydride serves as a reducing agent, the pH of the synthesized silver nano-cluster is adjusted twice, and the silver nano-cluster with the strong fluorescence emission function and good stability can be obtained. The maximum excitation wavelength of the synthesized silver nano-cluster is 335.0 nm, the maximum fluorescence emission wavelength is 410.0 nm, the grain diameter of the silver nano-cluster mainly ranges from 0.68 nm to 2.99 nm, and the average grain diameter is 1.74 nm. The synthesizing method has the beneficial effects that the synthesized raw material is easy to obtain, the system is simple, the synthesizing is rapid, and the fluorescence property is stable, and large-scale synthesizing can be achieved.

The invention discloses a formaldehyde-resistant self-cleaning wall paint and a preparation method thereof. The formaldehyde-resistant self-cleaning wall paint includes raw materials: acrylic ester monomer, polychromic acid, dispersant, defoamer, propylene glycol, and synthetic Membrane aids, diatomaceous earth, guanidine-containing hydrophilic compounds, thickeners, deionized water, pH regulators, fillers, by adding polychromic acid to the wall paint as an anti-formaldehyde agent, the wall surface The formaldehyde in contact is cured by chemical reaction; by introducing the guanidine-containing hydrophilic compound into the polymer during the emulsion polymerization of the acrylate monomer, the polyethylene glycol group contained increases the hydrophilicity of the polymer, and the contained The biguanide group can kill biomass and achieve excellent formaldehyde resistance and self-cleaning properties. The method of the invention is simple, does not need a special reaction process, and can be realized relying on the emulsion polymerization reaction.

The invention discloses an anodic oxidation pretreatment method for an environment-friendly titanium alloy. The anodic oxidation pretreatment method is characterized in that an anodic oxidation treatment solution is composed of chromotropic acid, oxalic acid and other substances. The pretreatment solution is formed by adding 1-5g of chromotropic acid and 5-10g of oxalic acid into 1L of deionized water. The anodic oxidation pretreatment method disclosed by the invention comprises the steps of: ultrasonic cleaning; alkali washing and oil removing; pretreatment; and deionized water cleaning. The anodic oxidation pretreatment method disclosed by the invention is used for effectively reducing the damage of strong acidic materials such as hydrofluoric acid, nitric acid and the like introduced to the current anodic oxidation pretreatment process to human bodies and the environment and effectively improving the condition of high treatment difficulty of wastes on the premise of ensuring the surface activation, the smooth finish and the subsequent anodic oxidation filming effect. The anodic oxidation pretreatment method for the environment-friendly titanium alloy is convenient to operate, simple in process, stable in component and easy to detect, and new concepts of green and safe production and sustainable development are realized.

The invention relates to a process utilizing H acid mother liquor to recover and produce chromotropic acid sodium salt, belonging to the technical field of organic chemistry. The process comprises the following steps of utilizing the H acid mother liquor for extracting and concentrating and separating organic matters; and adding sulfuric acid and hot water into a high-pressure hydrolyzing reactor for high-pressure hydrolyzing, then carrying out segregation, suction filtration, washing and drying, and finally obtaining a chromotropic acid sodium salt finished-product. With the adoption of the process, the organic components in the H acid mother liquor are recovered, the multiple components are successfully changed into single-component chromotropic acid through a chemical process, and the color spectrum and the chemical content are more than 96 percent. The extract liquor of the H acid mother liquor in the prior art cannot be recovered, and the organic matters can be processed only through high-temperature incineration. Compared with the prior art, the method has the advantages that the wastewater treatment cost is reduced, the abandoned pollutants are recycled, and the benefit is created.

The invention discloses a method for identifying sodium carbonate and sodium bicarbonate solution through chromotropic acid 2R-alcoholic solution. The method comprises the following steps: taking two small test tubes and respectively adding 2ml sodium carbonate and sodium bicarbonate solution; mixing chromotropic acid 2R with alcoholic solution with 20% of volume percent concentration of ethyl alcohol, thereby acquiring the red chromotropic acid 2R-alcoholic solution in which the volume ratio of chromotropic acid 2R to alcoholic solution is 0.0025%; respectively adding 1 drop of chromotropic acid 2R-alcoholic solution into the two small test tubes, wherein the red chromotropic acid 2R-alcoholic solution is faded to be colorless under the effect of the sodium carbonate solution, but the solution cannot be faded under the effect of the sodium bicarbonate solution and still is in original red color of the chromotropic acid 2R-alcoholic solution. According to the method provided by the invention, the problem of quickly identifying the sodium carbonate solution and the sodium bicarbonate solution which are both colorless and transparent can be effectively solved; better service can be supplied for production, life, scientific research and teaching; the device is simple; the operation is convenient; the drugs can be easily acquired; the phenomenon is obvious; the effect is good.