18 results about "Picric acid" patented technology

The invention relates to the technical field of pharmaceutical analysis, in particular to a method for detecting the content of guanidine nitrate by precolumn derivatization-high performance liquid chromatography, which comprises the following steps: oscillating and uniformly mixing a guanidine nitrate reference substance or sample and pure water at room temperature, adding sulfuric acid concentrated liquor in cold water bath to perform derivatization reaction, after the reaction is finished, placing at room temperature, and performing column chromatography to obtain the guanidine nitrate content. Adding liquid caustic soda for neutralization, carrying out gradient constant volume by using a mobile phase, and filtering by using a microporous filter membrane to respectively obtain a derivatization reference solution and a derivatization sample solution; and respectively injecting the derivatization reference substance solution and the derivatization sample solution into HPLC, recording peak areas, and calculating the content of guanidine nitrate in the sample by adopting an external standard method. The guanidine nitrate sample is pretreated through the precolumn derivatization reaction, the guanidine nitrate derivative generated through the reaction has the advantages of being high in stability and easy to separate, ammonium nitrate and nitric acid impurities can be effectively prevented from interfering the detection result, the explosive picric acid is not adopted in the detection method, and the detection method is simple, safe and easy to implement.

The invention discloses a composite propellant containing a high-nitrogen ferrocene derivative and a preparation method of the composite propellant. The composite propellant is prepared from the following components: 14.05% of hydroxyl-terminated polybutadiene (HTPB), 7.03% of diisooctyl sebacate (DOS), 0.92% of 2, 4-toluene diisocyanate (TDI), 1% of the high-nitrogen ferrocene derivative, 59% of ammonium perchlorate (AP) and 18.00% of aluminum powder (Al). N, N-dimethylaminomethylferrocene in the three high-nitrogen ferrocene derivatives has the effects of improving the burning rate of the composite propellant and reducing the pressure index as the ferrocene derivative, nitrate, picric acid, 3-nitro-1, 2, 4-triazole-5-ketone and the like are rich in C, H, O and N elements, and are similar to oxidizing agents such as typical components ammonium nitrate, HMD and the like in the composite propellant; the fuel can be decomposed to provide energy for propellant combustion; the propellant has a low combustion rate pressure index in a pressure range of 1-10 MPa, and has more excellent combustion stability.

The invention relates to the technical field of Stefan acid purification, in particular to a method for purifying Stefan acid from a dinitrobenzene nitration byproduct mixture, which comprises the following steps: S1, dissolving the dinitrobenzene nitration byproduct mixture in water, adjusting the pH value to be alkaline, and filtering to obtain filtrate and filter residue dinitrobenzene solid; s2, adding the filtrate into an organic solvent, extracting, separating liquid, and retaining a water phase; and S3, adjusting the pH value of the water phase to be acidic, heating for acid precipitation, and then cooling for crystallization to obtain a mixed crystal of Stefan acid and picric acid. And S4, heating and mixing the mixed crystal and toluene, and filtering to obtain the high-purity Stefan acid. According to the method, efficient separation is realized through a two-step core process of'alkali dissolution-acidification 'and'selective dissolution'. In the final product, the content of dinitrobenzene can be reduced to 0%, the content of picric acid can be reduced to 1% or below, and the purity of Stefan acid can reach 99% or above.

The application discloses an electrolyte additive, a preparation method thereof, an electrolyte and a lithium ion battery. The preparation method of the electrolyte additive comprises the following steps: dissolving picric acid in an organic solution to obtain an additive solution, wherein the organic solution contains at least one element selected from B, F and N; and crystallizing and precipitating the electrolyte additive from the additive solution. The electrolyte additive is beneficial to making the polymerization layer and SEI film harder and more stable, and is beneficial to inhibiting the growth of lithium dendrites. The electrolyte added with the electrolyte additive can generate an electro-polymerization reaction in the process of battery charging and discharging, thereby reducing the loss of the electrolyte and lithium metal, reducing the resistance of the lithium ion battery and improving the cycle performance of the lithium ion battery. The lithium ion battery provided by the application contains the electrolyte added with the electrolyte additive, and thus has lower resistance and better cycle performance.

The application relates to the technical field of metal material detection, and provides an alloy spring steel austenite grain size detection method, which comprises the following steps: carrying out heating and heat preservation treatment on an alloy spring steel sample, the temperature of the heating and heat preservation treatment is in a grain boundary segregation sensitization temperature interval of phosphorus elements, so that the phosphorus elements are segregated at original austenite grain boundaries; carrying out metallographic sampling on the alloy spring steel sample after the heating and heat preservation treatment to obtain a metallographic sample; carrying out corrosion treatment on the metallographic sample under heating conditions by using a water-based etching liquid, the water-based etching liquid comprises picric acid and a surfactant; and observing the metallographic sample after the corrosion treatment to obtain austenite grain size. The application simplifies a detection process, clearly shows original austenite grain boundaries, and improves grading accuracy.

A method for predicting the austenite grain size of cold-extruded gear steel after carburizing belongs to the field of metal material testing technology. The method mainly includes the following steps: taking samples from hot-rolled round steel and processing them into specimens of specified dimensions; normalizing the specimens; then performing spheroidizing annealing; cold-heading the spheroidized annealed specimens; then performing pseudo-carburizing treatment; finally, preparing the specimens into metallographic samples, etching them with picric acid aqueous solution, and observing the grain size under a metallographic microscope. This invention, through a coupled process of heat treatment and cold heading deformation, can effectively detect the austenite grain size of cold-extruded gear steel after carburizing, directly characterizing the material's resistance to grain coarsening during the carburizing process after cold extrusion.

The invention discloses application of a compound based on Schiff base as a fluorescent probe in detection of explosive picric acid. The structural formula of the compound containing the Schiff base structure is shown in the formula I. The specific structure is as follows: the probe has the characteristics of high selectivity, quick response and high sensitivity on picric acid. On the basis, the limitation of a single detection form is broken through, the sensor is developed into a dual-mode fluorescence sensor, and the sensor can stably exist in a system mixed with various different indicators; meanwhile, the dual-mode fluorescence sensor is flexibly combined with different material carriers such as PVA hydrogel, a PVDF film, a filter paper strip and the like, and the real-time, portable and intelligent field detection requirements can be met through'deep learning 'and small lightweight programs. In addition, the detection method is simple and convenient to operate and low in cost, and has the potential of large-scale popularization and application.

The application discloses a metallographic structure display corrosion agent suitable for Cu-containing martensite bearing steel and a display method, and the corrosion agent contains 3-5g of picric acid, 0.9-1.3g of hydrogen peroxide, 1.2-1.8g of hydrofluoric acid, 2.5-4g of nitric acid, 0.5-1g of fatty alcohol polyoxyethylene ether, 0.4-0.8g of fatty alcohol polyoxyethylene ether sodium sulfate and 0.3-0.5g of sodium dodecyl benzene sulfonate in 80-100g of water. According to the characteristics of the Cu-containing bearing steel, the corrosion agent formula is re-designed through experiments, the multi-acid is used in combination with multiple surfactants and oxidants, and the corrosion time can be controlled and the fine crystal phase structure morphology of the tempered martensite and the reversed austenite in the bearing steel can be obviously displayed.

The invention discloses a rapid cyanogenic glycoside detection kit and a detection method, and belongs to the technical field of agricultural product detection. The kit comprises an enzymolysis reaction reagent and a hydrocyanic acid detection reagent, the enzymatic hydrolysis reaction reagent is prepared from beta-glucosidase, 1-ethyl-3-methylimidazole diethyl phosphate salt and rhamnolipid, and the enzymatic hydrolysis reaction reagent is prepared from beta-glucosidase, 1-ethyl-3-methylimidazole diethyl phosphate salt and rhamnolipid; the hydrocyanic acid detection reagent comprises a picric acid test strip, tartaric acid and a saturated sodium carbonate solution. The detection method comprises the following steps: adding an enzymolysis reaction reagent into a sample to be detected, hydrolyzing cyanogenic glycoside into cyanide, and adding tartaric acid to convert into volatile hydrocyanic acid; a picric acid test strip wetted by a saturated sodium carbonate solution is used for adsorption, and hydrocyanic acid and sodium picrate on the test strip act to generate sodium isocyanurate; and observing the color change of the test strip for qualitative and / or quantitative detection. The detection kit provided by the invention is convenient and rapid, has a short detection period, and is convenient for timely detection in links of agricultural product production, processing, storage, sales and the like.

The invention provides a method for detecting a martensitic structure of a steel rail. According to the method, the polishing precision of the steel rail sample can be improved and the surface roughness can be reduced by combining electrolytic polishing comprising specific components and mechanical light polishing. Furthermore, according to the method, corrosion is carried out after mechanical polishing, the corrosive liquid comprising an alcohol and nitric acid mixed solution and a picric acid alcohol saturated solution is adopted, rapid display of martensite can be achieved, the overall method is simple in process and easy to operate, and the test efficiency is improved.

The invention belongs to the technical field of martensitic stainless steel performance detection, and relates to a 4Cr13 stainless steel metallographic etchant and a corrosion method for displaying carbides, and the etchant is prepared from the following components: 10-15 mL of glacial acetic acid, 1-2 g of ammonium persulfate, 0.5-1 g of sodium molybdate, 70-80 mL of absolute ethyl alcohol and 10-15 mL of deionized water. Glacial acetic acid is organic weak acid, and compared with inorganic acid, glacial acetic acid is more environment-friendly and mild and can reduce grain boundary over-corrosion; ammonium persulfate is a mild oxidant, releases active oxygen in an acidic environment, selectively destroys a passive film, enhances grain boundary and phase boundary corrosion, and avoids use of strong acid or heavy metal. Molybdate ions in sodium molybdate are adsorbed on the surface of carbide to generate a MoO2 / MoO3 nano film, blue-black contrast is generated through light interference, the contrast of the carbide is remarkably improved, and toxic picric acid is replaced. Absolute ethyl alcohol is an environment-friendly organic solvent, so that the reaction rate is reduced, the uniformity is improved, and the method is environment-friendly.

The application belongs to the technical field of fluorescent sensing detection, and particularly relates to a MOF-based composite material for multiple detection of Fe 3+ , MnO4 ‑ and picric acid and a preparation method thereof. The application prepares ZIF-8 by taking Zn(NO3)6H2O and 2-methyl imidazole as raw materials; and then the MOF-based composite material Flu@ZIF-8 is obtained by soaking in a Flu methanol solution. The application is the first multi-element fluorescent sensor based on the confinement effect of ZIF-8, and can realize efficient detection of Fe 3+ , MnO4 ‑ and PA synchronously, break through the limitation of traditional single target detection, effectively inhibit the ACQ effect of Flu, avoid solution pollution problems, and retain excellent optical properties. The material still maintains structural integrity and fluorescent response ability after multiple regeneration cycles, and reduces the cost of actual application.

Pyrotechnic mixture with potassium benzanate, said pyrotechnic mixture comprising a binary or ternary intermixture comprising at least two selected from potassium benzanate, copper picramate and potassium picrate.

The present application relates to the technical field of multifunctional light-emitting liquid crystal, and particularly relates to a pyrone multifunctional light-emitting liquid crystal compound, a preparation method and application thereof, and a structure of the compound is shown as formula (I), wherein n is 10, 12 or 14. The target product can be prepared by reacting 3,4,5-trialkoxybenzaldehyde and 2,6-dimethyl-gamma-pyrone in the presence of sodium tert-butoxide in anhydrous ethanol, and then purified by recrystallization. The method is suitable for industrial production, because raw materials are easy to obtain, reaction conditions are mild, and purification is simple. The pyrone light-emitting liquid crystal compound provided by the present application combines the excellent light-emitting performance of pyrone and the supramolecular self-assembly characteristics of liquid crystal, and can be applied to the fields of bistable light-emitting materials, ferroelectric materials, light-emitting organic gels and picric acid fluorescent probes, and shows a broad application prospect.

This invention discloses a polysubstituted furanopyridine compound, its preparation method, and its application in pharmaceutical preparation. The compound is a triphenyl-substituted furanopyridine compound. This series of compounds possesses excellent fluorescence properties and can be used as novel fluorescent sensing materials for the efficient detection of aromatic explosives, especially exhibiting rapid response to picric acid and high sensitivity in test strip detection systems. Furthermore, this series of compounds also exhibits excellent antibacterial and bacteriostatic functions, demonstrating its potential application value in the biomedical field. This invention also provides a method for preparing the above-mentioned polysubstituted furanopyridine compound, using acetophenone compounds and polysubstituted furans as raw materials. This synthetic method has advantages such as simple operation, wide substrate applicability, high atom utilization, and excellent yield. This synthetic strategy overcomes the limitations of traditional methods, eliminating the need for expensive catalysts, and achieving a target product yield of up to 80%.

The invention discloses an etching solution for displaying an original austenite grain boundary of low-alloy martensite wear-resistant steel. The etching solution is prepared from six components including an H2O2 solution with the volume concentration of 30%, FeCl3. 6H2O, CuSO4. 5H2O, oxalic acid, lauryl sodium sulfate and water. The preparation method comprises the following steps: dissolving lauryl sodium sulfate in water at normal temperature, and then heating to boiling; and naturally cooling to normal temperature, adding FeCl3. 6H2O, CuSO4. 5H2O, oxalic acid and a H2O2 solution with the volume concentration of 30%, and uniformly stirring and dissolving, thereby obtaining the catalyst. The etching solution provided by the invention is suitable for clearly displaying original austenite grain boundaries of low-alloy martensite wear-resistant steel with multiple hardness levels such as NM400, NM450, NM500 and NM550, hazardous chemicals such as picric acid and aqua regia do not need to be used, the operation is simple, and the cost is low.

The invention discloses a method for displaying an original austenite grain boundary of spring steel after thermal compression, and belongs to the technical field of physical detection. The method aims at solving the problems that when the original austenite grain boundary of the hot compression spring steel is displayed through a traditional method, display is difficult, and potential safety hazards are caused by using corrosive agents such as picric acid. The method comprises the following steps: firstly, splitting a thermal compression sample along a compression direction, and grinding and polishing the section of the thermal compression sample to obtain a scratch-free mirror surface; then, the polished surface faces upwards, heat preservation is conducted for 15-30 min in an air furnace at the temperature of 850-870 DEG C, and then water quenching is conducted; and finally, corroding the surface of the sample for 5-10 seconds by adopting a nitric acid alcohol solution with the volume concentration of 4%, washing, dehydrating and drying, so that the clear original austenite grain boundary can be observed under a metallographic microscope. Through the steps, clear display of the original austenite grain boundary after hot compression of the spring steel is achieved. According to the method, a nitric acid alcohol solution is adopted to replace a traditional picric acid solution, so that the operation safety is improved; and specific heat treatment is combined with a corrosion process, so that the definition and the stability of crystal boundary display are ensured.

The invention discloses a preparation method of a fluorescent probe based on a carbon dot-metal organic framework material and application of the fluorescent probe in picric acid detection. The preparation method comprises the following steps: carrying out hydrothermal reaction on pine fruit powder to prepare blue carbon dots; and reacting the blue carbon dots with zirconium tetrachloride and 2-aminoterephthalic acid at 80-160 DEG C for 8-28 hours to obtain the fluorescent probe. The fluorescent probe can be used for efficiently and selectively detecting trace picric acid in an environmental sample. The fluorescent probe prepared by the invention has high dispersity, good stability and excellent fluorescence stability, and rapid, simple, high-sensitivity and high-selectivity analysis of trace picric acid in an environmental matrix is realized by utilizing an inner filter effect generated between the fluorescent probe and picric acid.