15 results about "Purplish red" patented technology

The invention relates to the technical field of titration detection in analytical chemistry, in particular to a thymol phenolphthalein-TBPE composite indicated cyanide high-precision detection method which comprises the following steps: step 1, after a water sample to be detected is distilled and separated, adjusting the pH value of distillate to a strong alkaline environment required by thymol phenolphthalein color development; 2, adding a composite indicator containing thymol phenolphthalein and tetrabromo phenolphthalein ethyl ester, wherein the mass ratio of the two components in the composite indicator is determined through a color change sensitivity optimization experiment; step 3, titrating with a silver nitrate solution, and judging an end point according to three-order color mutation: the initial state is light yellow, the intermediate state is green, and the end point state is purple red; and 4, adding an auxiliary masking agent before titration, and blocking the reaction between the auxiliary masking agent and silver ions by preferentially complexing interference ions. By optimizing the ratio of the composite indicator and using the masking agent, interference of other substances can be effectively prevented, and accurate detection of cyanide is ensured.

This invention relates to the field of food testing technology, and more particularly to a colorimetric LAMP method for the simultaneous visual detection of Vibrio vulnificus and Vibrio alginolyticus. The method employs a LAMP detection system composed of DNA-functionalized gold nanospheres and gold nanorods for detecting Vibrio vulnificus and Vibrio alginolyticus, respectively, and LAMP primer pairs. This allows for the detection and determination of the following states of Vibrio vulnificus and Vibrio alginolyticus: when neither pathogen is present, the solution is transparent; when both pathogens are present, the solution is purplish-red; when only Vibrio alginolyticus is present, the solution is gray; and when only Vibrio vulnificus is present, the solution is purple. This method can accurately determine the presence or absence of Vibrio vulnificus and Vibrio alginolyticus, and the specific type of bacteria, avoiding misjudgments, missed detections, and inaccurate traceability of these two types of pathogen contamination in food safety monitoring, clinical practice, and aquaculture protection.

The invention discloses a method for detecting the content of aluminum oxide in a high-aluminum material, based on the principle of EDTA complexometric titration, EDTA and aluminum ions form a stable complex (1gK = 16.1) in a buffer system with the pH value of 6.0, and the end point is judged according to the color change (brilliant yellow-purplish red) of an indicator, the method has the advantages that insoluble substances such as aluminum nitride can be completely decomposed by adopting alkali fusion pretreatment of YST 575.1, and full release of aluminum elements is ensured; by combining a GB / T 6900 titration system and optimizing a buffer condition and a masking agent, interference of iron (III), calcium, magnesium and the like is effectively overcome, so that the method has high accuracy and strong anti-interference performance (can tolerate Cl <-> of less than or equal to 3.5% and Fe of less than or equal to 1.8%), and is suitable for detection of aluminum ash residue recycling products with complex components.

The application discloses an indicator for indicating Fe 3+ in an acidic medium and a preparation method and application thereof. The indicator contains a salicylic acid structure in the structure, when Fe 3+ is contained in galvanized steel, Fe 3+ can be complexed with the -COOH group and -OH group in the indicator, the solution changes from colorless to purple red, naked eye identification can be realized, meanwhile, ultraviolet-visible absorption spectrum is enhanced, thereby realizing qualitative and quantitative detection of Fe 3+ . In addition, the indicator provided by the application has strong sensitivity in recognizing Fe 3+ , can effectively realize qualitative and quantitative detection of Fe 3+ , and is not influenced by other analytes such as Na + , Ba 2+ , Hg 2+ , Cu 2+ , Ni 2+ , Zn 2+ , Mg 2+ , Ca 2+ , Cd 2+ , Cr 3+ and the like, and has excellent selectivity.

The invention discloses a vanadium ion valence rapid qualitative detection test piece and a preparation method thereof. The preparation method comprises the following steps: preparing a solution A containing a pH buffer agent; preparing a solution B containing N-phenyl anthranilic acid; and dipping the water-absorbing material in a mixed solution of the solution A and the solution B, taking out and drying. The concentration of the N-phenyl anthranilic acid in the mixed solution is 0.2-0.5 wt%, the concentration of the anhydrous sodium carbonate in the mixed solution is 0.1-0.3 wt%, and the concentration of the phosphoric acid in the mixed solution is 0.2-0.5 wt%. The water-absorbing material is soaked in a mixed solution, taken out, dried, cut into a certain size, pasted on a substrate, sealed and stored. When the electrolyte contains pentavalent vanadium ions and wets the test piece, the test piece develops purple red, and when the pentavalent vanadium ions are all reduced into tetravalent vanadium ions, the test piece develops sky blue.

The application relates to preparation and application of a dye-functionalized rare earth metal organic framework material capable of recognizing sulfur ions: S1, selecting raw materials, terbium nitrate, pyrazine tetramethanic acid, potassium hydroxide and rhodamine B; S2, dissolving the pyrazine tetramethanic acid in distilled water and stirring; S3, adding the Tb(NO3)3.6H2O methanol solution obtained in S2 into the solution, and stirring; S4, adding the KOH solution into the solution obtained in S3, and stirring; S5, standing, centrifugally collecting the white precipitate, and drying after washing to obtain the white rare earth metal organic framework material; S6, immersing the sample in different concentrations of rhodamine B dyes for treatment; S7, collecting the purple red precipitate in S6, and drying to obtain the dye-functionalized rare earth metal organic framework material; and S8, using the obtained dye-functionalized rare earth metal organic framework material for sulfur ion detection. The preparation of the dye-coated rare earth metal organic framework is that the rare earth metal organic framework is coated with different concentrations of rhodamine B dyes, can be used as a ratio type fluorescent probe, and can more sensitively and accurately recognize and detect sulfur ions.

This invention discloses a method for measuring the total iron content in EDTA chemical cleaning solution for power plant boilers, relating to the field of chemical cleaning technology for power plant boilers. The method includes: injecting the EDTA cleaning solution into a UV reactor and diluting it with demineralized water; adjusting the pH of the solution in the UV reactor to acidic using hydrochloric acid and ammonia, then adding persulfate solution, heating the reaction, and allowing complete digestion; transferring the solution from the UV reactor to a reaction flask, adding sulfosalicylic acid as an indicator, and titrating with EDTA standard solution until the purple-red color changes to pale yellow as the endpoint, recording the volume of EDTA consumed, and calculating the total iron content in the chemical cleaning solution. This invention features high accuracy, simple operation, and fast detection speed.

The present invention provides a fluorescent probe and its preparation method and application. The structural formula of the fluorescent probe is as follows: The preparation method is: 7-N,N-diethylamino-2H-chromene-3-aldehyde, 4-methyl-N-(4'-boronic acid pinacol benzyl) pyridine bromide, a catalyst and a solvent are stirred, mixed and heated under reflux for reaction, and then filtered and recrystallized to obtain a fluorescent probe product. The probe has good water solubility, biocompatibility and is positively charged. The solution color is purple-red, the absorption peak is at 540nm, and the fluorescence peak is at 720nm (near-infrared region), which can be used for near-infrared biological fluorescence imaging. The probe has the property of realizing ratiometric colorimetry and ratiometric fluorescence response to peroxynitrite. After reacting with peroxynitrite in a CH3CN-pbs (v / v=1:1, v / v, pH=7.4) solution, the color of the probe solution changes from purple-red to slightly yellow, A 410nm / A 540nm The probe has a linear relationship with the concentration of peroxynitrite in the range of 0 to 10 μM, with a detection limit of 95 nM. The red fluorescence of the probe gradually weakens at 720 nm and the bright yellow fluorescence gradually increases at 568 nm. 568nm / I 720nm The probe has a linear relationship with peroxynitrite concentration in the range of 0 to 16 μM, with a detection limit of 10 nM. The probe has the advantages of high sensitivity, low detection limit, and low background fluorescence interference.

According to the multicolor leuco dye developing ink composition and the preparation method thereof disclosed by the invention, by designing three types of leuco dyes of purple red, yellow and ink colors and optimizing the molecular structure and response mechanism of the three types of leuco dyes, multicolor synergistic developing is realized in a breakthrough manner, and the color gamut coverage of a developing system is enriched; dye combinations with structural complementarity and thermal / optical / acid-base response differentiation characteristics are selected, and a proper color developing agent and carrier system is matched, so that the dispersion stability and the color developing resolution of a multi-dye composite system are remarkably improved, and color developing cross interference is avoided; by optimizing the ratio of the dye to the color developing agent and finely adjusting the color developing trigger conditions (such as temperature, pH value and the like), the consistency control of the color developing intensity and the color tone is realized, and the reproducibility and the practicability of an ink printing pattern in different batches are remarkably improved; and a low-toxicity environment-friendly solvent or a water-based dispersion system is preferably selected as a carrier, so that the obtained ink is more suitable for environment-friendly requirements of green printing and special scenes.

The invention discloses a method for detecting copper ions in industrial copper sulfate. The method comprises the following steps: (1) weighing 0.2-0.5 g of a to-be-detected sample with the accuracy of 0.0001 g, dissolving the to-be-detected sample in deionized water, transferring the to-be-detected sample into a 100-500mL volumetric flask, fixing the volume, and uniformly mixing to obtain a sample solution; (2) putting 25-50 mL of the sample solution into a conical flask, adding 5-10 mL of a thiourea solution, 5-10 mL of a triethanolamine solution, 20-25 mL of a boric acid buffer solution with the pH value of 8, and a red and violet acid ammonium indicator, and titrating with an EDTA standard solution until the color of the solution is changed from purple red to blue; and (3) calculating the content of the copper ions in the to-be-detected sample. Compared with an ammonia-ammonium chloride buffer solution with the pH value of 10, the boric acid buffer solution with the pH value of 8 is used in the method, the titration end point is easy to observe, and the accuracy, the detection efficiency and the reproducibility of a detection result are improved.

The application belongs to the coloring technical field of decorative products, and provides a novel purple-red inorganic colorant. 1‑x Co x B4O7, wherein the value range of x is 0-1, and the purple-red inorganic colorant can exhibit bright purple or purple-red in a low-temperature environment (lower than 800 DEG C) and has excellent coloring characteristics; the application prepares a novel purple-red inorganic colorant through the magnesium borate doped with cobalt material Mg 1‑ x Co x B4O7, which is bright in color, strong in coloring power and capable of meeting coloring requirements in different fields; meanwhile, different shades of purple or purple-red can be obtained by adjusting the doping amount (x value) of Co, so that diversified color requirements are met.

The present invention relates to the field of detection technology, and discloses an application of a cobalt-based metal-hydrogen bond-organic framework material in detecting pH value. The chemical formula of the cobalt-based metal-hydrogen bond-organic framework material is Co(M)6CO3·m(H2O), where M is imidazole and m is 6-9. The range of pH value detected by the cobalt-based metal-hydrogen bond-organic framework material is 2.0-2.4. When the pH value of the solution detected by the cobalt-based metal-hydrogen bond-organic framework material is 2.0-2.4, the color change of the solid precipitate is from pink to purplish red to purple, and its detection accuracy can reach an interval of 0.1 for the pH value.

The invention discloses a KMnO4 colorimetric information card sensor for rapidly detecting xanthine oxidase in liver cancer CTCs and application of the KMnO4 colorimetric information card sensor. According to the method, the color of KMnO4 is gradually changed into pink, brown yellow and light yellow from amaranth by utilizing the reduction effect of H2O2 on KMnO4, visual detection of H2O2 is realized, the process can be completed within 1 minute, meanwhile, the change of an RGB chromaticity space and an absorbance value at the position of 526 nm can be caused, and an R / G value and an A526 value are in linear correlation with the concentration of H2O2 within a certain range. XOD can selectively oxidize xanthine (XA) to generate H2O2, KMnO4 is reduced in the presence of H2O2, the color of KMnO4 is changed from dark purple to dark brown and then to light yellow, and visual detection of XOD and XA is achieved. By adjusting the concentration of the XOD or the XA, a detection method of the XOD can be constructed. Finally, the sensing method is applied to analysis of the concentration of XOD in liver cancer CTCs, and it is found that the expression quantity is higher than that of normal cells. The method has the advantages of simplicity in operation, low cost, visualization, high sensitivity and good specificity.

The invention discloses a rapid detection method for total hardness of domestic drinking water. The method comprises the following steps: respectively and accurately measuring three 50mL water samples in a 150ml conical flask, marking as 1, 2 and 3, respectively and sequentially adding 1mL-2mL buffer solution and 5 drops of chrome black T indicator, immediately titrating by using a Na2EDTA standard solution until the color of the solution is changed into pure blue from amaranth and does not fade within half a minute, immediately stopping titration, recording the consumption volume of EDTA, if the water sample contains metal interference ions, additionally taking the water sample, and if the water sample contains metal interference ions, recording the consumption volume of the EDTA. 0.5 mL of hydroxylamine hydrochloride and sodium sulfide solution or 0.5 mL of potassium cyanide solution is added for parallel titration, when the content of bicarbonate of calcium and magnesium in a water sample is large, the water sample needs to be acidified in advance, carbon dioxide is removed through heating, suspended solids or colloidal organic matter contained in the water sample can affect observation of an end point, the water sample can be evaporated to dryness in advance and ashed at 550 DEG C, residues are dissolved with pure water, then titration is conducted, and the content of calcium and magnesium in the water sample is measured. Each water sample is subjected to parallel titration operation for five times, each group of numerical values is recorded, the average value of the numerical values is taken, the total hardness of the tap water to be measured is calculated, and the total hardness limit value is 450 mg / L, soft water is 0-150 mg / L, medium hard water is 151-300 mg / L, hard water is 301-450 mg / L, and hard water is above 450 mg / L. The method can be used for rapidly detecting the total hardness of the domestic drinking water.

The invention relates to the technical field of rapid screening kits, in particular to a use method of a rapid screening kit for rapidly detecting formaldehyde, which comprises the following steps: dissolving 0.5% AHMT in a 0.1 M hydrochloric acid solution, mixing with NaOH solid powder to prepare a color developing agent, treating a sample, taking the treated sample as a sample to-be-detected solution, diluting the sample to-be-detected solution with the dilution ratio of 10, taking out a detection hole strip, and detecting the formaldehyde in the sample to-be-detected solution. Adding one drop of a color developing agent and two drops of a 3% hydrogen peroxide solution into the detection hole, adding three drops of a sample to-be-detected solution by using a suction tube, mixing and standing for 7 minutes, and finally interpreting a result through a colorimetric card and multiplying the result by a dilution multiple to obtain the content of formaldehyde. According to the method, an optimized AHMT color development system is adopted, the AHMT color development system is specifically combined with formaldehyde under the alkaline condition and oxidized to generate a stable purplish red complex, the detection sensitivity is remarkably improved, and meanwhile, the color development reaction has excellent anti-interference capacity by strictly controlling the solution proportion and reaction conditions.