441 results about "Residual solvent" patented technology

The invention discloses a method for preparing tegorasone pyroglutamate, and the prepared tegorasone pyroglutamate product has the advantages of reduced residual solvent content, good stability, and facilitation of the improvement of the product quality and the guarantee of the medication safety. The preparation method is simple and rapid in preparation process, beneficial to saving of production cost and suitable for industrial production.

The invention relates to the technical field of toughening agents, in particular to a hyperbranched epoxy resin modified MBS toughening agent and a preparation method thereof.The preparation method comprises the following steps that (S1) a cyclotriazine compound, polyglycidyl ether and a catalyst are added into an organic solvent to be mixed, a reaction is conducted for 8-72 h at the temperature of 30-150 DEG C under the protection of nitrogen, and after the reaction is completed, alcohol precipitation and drying are conducted to obtain a hyperbranched epoxy resin modified MBS toughening agent; the hyperbranched epoxy resin is obtained; (S2) adding the hyperbranched epoxy resin into the solvent A, uniformly mixing, then adding MBS resin, stirring for 0.5-1 hour at a high speed under the condition of room temperature, then heating to 70-110 DEG C, stirring for 0.5-1 hour, and removing the residual solvent to obtain the hyperbranched epoxy resin modified MBS toughening agent, and by utilizing the hyperbranched characteristic of the resin, enabling the modified MBS toughening agent to be used for preparing the hyperbranched epoxy resin modified MBS toughening agent. The toughening effect can be achieved by adding a small amount of the toughening agent into common epoxy resin.

The invention discloses a post-treatment system and process for PBF printing plastic parts, and the post-treatment system comprises a solvent storage bottle, a part treatment assembly and a solvent recovery assembly; a solvent is stored in the solvent storage bottle; the part processing assembly is used for carrying out fairing treatment on the PBF printing plastic part; the solvent recovery assembly is used for recovering the vaporized solvent in the part treatment assembly and re-liquefying and storing the vaporized solvent; the output end of the solvent storage bottle is connected with the input end of a solvent cabin of the part treatment assembly through a peristaltic pump, and the part treatment assembly is connected with the solvent recovery assembly through a recovery valve. According to the principle that the solvent is rapidly vaporized under the pressure difference, then uniformly reaches any surface position of the workpiece and is condensed and liquefied again, the surface defects of the workpiece are gradually dissolved and leveled under the action of the solvent, then the solvent steam is liquefied and recovered again, and the residual solvent on the surface of the workpiece is removed. The common surface roughness problem of the 3D printing plastic part can be effectively improved, and the appearance quality of the part is improved.

The invention relates to the technical field of membrane separation, in particular to a composite forward osmosis membrane based on mussel bionic interface enhancement and a preparation method thereof. The preparation method comprises the following steps: immersing a base material in a dopamine hydrochloride solution for oscillation reaction to obtain a modified base material; the surface of the modified base material is coated with a membrane casting solution in a blade coating mode, then phase inversion is carried out, the residual solvent is removed, then airing is carried out, and the composite forward osmosis membrane based on mussel bionic interface enhancement is obtained. By introducing the mussel bionic polydopamine intermediate layer, the long-standing technical contradictions of poor interfacial compatibility and weak binding force between the hydrophobic substrate and the hydrophilic separation layer are ingeniously solved, and the internal concentration polarization effect is remarkably inhibited. The prepared composite membrane has the advantages of high water flux, low salt reverse flux, stable structure and the like, and has wide application prospects in the fields of water treatment and substance separation.

The invention discloses hydrogenated modified resin as well as a preparation method and application thereof, and belongs to the technical field of bio-based materials. The preparation method comprises the following steps: carrying out polymerization reaction on cyclopentadiene and derivatives thereof and norbornene monomers in the presence of a first solvent, and then adding modified monomers for continuous reaction; separating out the cycloolefin copolymer and reacting the cycloolefin copolymer with bio-based carboxylic acid in the presence of a second solvent to obtain a second polymerization solution; and removing unreacted monomers and residual solvents and oligomers, then carrying out a hydrogen reaction with deeply hydrogenated naphthenic oil under the action of a noble metal hydrogenation catalyst, and removing impurities, gel substances, residual solvents and oligomers to obtain the hydrogenated modified resin. The method is simple in process, easy to operate and mild in condition, the bio-based synthetic resin with medium-low molecular weight and high performance can be obtained, and the hydrogenated modified resin has excellent tackifying performance and can be applied to the fields of hot melt adhesives, automobile parts, packaging materials or medical equipment and the like.

The invention discloses a tolvaptan sodium phosphate crystal form. The X-ray powder diffraction pattern of the tolvaptan sodium phosphate crystal form has characteristic diffraction peaks at diffraction angles 2theta of 3.8 + / -0.2, 7.7 + / -0.2, 9.8 + / -0.2, 11.5 + / -0.2, 12.5 + / -0.2, 16.2 + / -0.2, 17.4 + / -0.2, 19.2 + / -0.2, 20.8 + / -0.2, 23.2 + / -0.2, 29.6 + / -0.2, 30.3 + / -0.2 and 31.4 + / -0.2. The invention also discloses a preparation method of the tolvaptan sodium phosphate crystal form. According to the preparation method, the flowability of crystal mush during crystallization is improved, the granular sensation is increased, the explosion separation phenomenon is eliminated, the residual solvent of the product is reduced, and the stability of the product is improved.

The invention belongs to the technical field of pharmaceutical analysis, and particularly relates to a method for determining a residual solvent in LXH-2103 by headspace gas chromatography. The determination method comprises the following steps: preparing a blank solution, a reference substance solution and a sample solution, respectively injecting the blank solution, the reference substance solution and the sample solution into a headspace for balancing, injecting the solutions into a gas chromatograph in a headspace sample injection manner, recording a chromatogram, and calculating the content according to a peak area by an external standard method; the residual solvent is absolute methanol, absolute ethyl alcohol, isopropanol, dichloromethane and methylbenzene. The method for determining the residual solvents in the LXH-2103 by using the headspace gas chromatography, provided by the invention, is high in sensitivity, good in repeatability and high in accuracy, and can be used for simultaneously detecting various residual solvents in the LXH-2103, so that the quality of the LXH-2103 is ensured, and the safety of clinical medication is improved.

The invention discloses a preparation method of a PA6 / PEO micro-nanofiber air filtering membrane with a bent form, which comprises the following steps: (1) weighing PA6 particles and PEO powder with a certain mass, and dissolving in a formic acid solution with the mass fraction of 88% to obtain a mixed solution; (2) stirring the mixed solution to obtain a PA6 / PEO spinning solution; (3) forming a fiber membrane under a room-temperature dry condition through a gas jet spinning machine; (4) drying overnight at 60 DEG C to remove the residual solvent; (5) performing heat treatment in a drying oven, and (6) at normal temperature, placing the fiber membrane subjected to heat treatment in a container, and adding deionized water to immerse the fiber membrane; (7) heating the container in a water bath, and repeating the water bath treatment twice; and (8) immediately taking out the sample after the reaction is finished, and performing vacuum drying treatment. According to the invention, oily and salty ultrafine particles can be efficiently filtered at the same time, and the technical problem that effective filtration of fine oily and salty particles is difficult to realize in the prior art is solved by optimizing the structural characteristics of the fiber membrane.

The invention belongs to the technical field of alkaline electrolyzed water, and relates to a preparation method of an LDH / PSF / PP composite anion exchange membrane, which comprises the following steps: step 1, uniformly dispersing PSF polymer molecules in a polar organic solution to form a PSF polymer solution; step 2, preparing LDH with a high specific surface area, and uniformly dispersing the LDH into the PSF polymer solution to prepare a membrane casting solution; 3, blade-coating the prepared membrane casting solution on a PP support net to form a serous membrane, and then transferring the composite membrane to a drying oven for a pre-evaporation process; step 4, transferring the pre-evaporated composite membrane into a coagulating bath for phase inversion, and curing the PSF in the coagulating bath due to solvent precipitation so as to form a solid composite membrane; and step 5, soaking the prepared solid composite membrane in deionized water to remove the residual solvent. The preparation method of the LDH / PSF / PP composite anion exchange membrane has the advantages of low surface resistance, high gas barrier property, high mechanical strength and capability of realizing large-scale preparation, and is a preparation method of the LDH / PSF / PP composite anion exchange membrane with relatively high innovativeness.

The invention discloses a preparation method and application of a polymer membrane based on solvent in-situ functionalization enhancement. The method comprises the following steps: dissolving a polymer raw material by adopting a polymerizable solvent to form a homogeneous membrane casting solution; then synchronously carrying out ultraviolet light induced polymerization on the residual solvent in the membrane in the membrane casting liquid phase separation forming process by utilizing a constant-temperature circulating coagulating bath carrying an ultraviolet light illumination system; performing drying treatment to obtain a flat plate / hollow fiber composite membrane; the method is applied to the aspects of seawater desalination, wastewater treatment, food processing, biological medicine, energy chemical industry and the like. By utilizing dual functions of the solvent, polymerized solvent molecules and macromolecular chains form a stable cross-linked interpenetrating network structure, functional design of the membrane is realized through customizability of the solvent, functionalization enhancement of the membrane is realized while the process is simplified, ultraviolet polymerization synchronously optimizes phase separation kinetics, and the performance of the membrane is improved. Uniform surface pore size distribution and efficient mass transfer channels are formed, and the advantages of high efficiency and customizability are shown.

The invention discloses a headspace gas chromatography detection method for simultaneously determining multiple residual solvents in pharmaceutical adjuvant hydroxypropyl methylcellulose. The headspace gas chromatography detection method comprises the following steps: preparing a reference solution containing the residual solvents; preparing a test solution of hydroxypropyl methylcellulose; respectively injecting the reference solution and the test solution into a headspace gas chromatograph for testing, and calculating the content of each residual solvent by peak area according to an external standard method; through accurate control of gas chromatography conditions, the method can accurately, rapidly and simultaneously detect the contents of residual methanol, isopropanol, dichloromethane, trichloromethane, benzene, trichloroethylene, dioxane and toluene in the pharmaceutical adjuvant hydroxypropyl methylcellulose, and has the advantages of simplicity and convenience in operation, high accuracy and sensitivity, good reproducibility and the like.

The invention discloses a sulfone polymer and a purification method thereof, belonging to the technical field of polymer material preparation. In the purification method of the sulfone polymer provided by the invention, a reaction solvent and a reaction solvent containing a porogen of a specific type and content are sequentially added at the end of a polymerization reaction, so that a loose porous structure can be formed on the surface of a precipitate in the subsequent precipitation process, and the residual solvent, reaction monomers and the like in the sulfone polymer are extracted in conjunction with subsequent crushing and washing, thereby obtaining a sulfone polymer with high purity, high yield and excellent performance. In addition, due to the formation of the loose porous structure, the purification method provided by the invention can greatly reduce the demand for washing water used in subsequent washing, thereby achieving the effect of energy saving and emission reduction.

A method for purifying sodium fluoride by using complexing crystallization belongs to the technical field of sodium fluoride purification, and comprises the following steps: preparing a dissolving solution; complexing the dissolving solution with a complexing agent to obtain a complexing solution; the complexing solution is pumped into membrane separators, the complexing solution passes through the first membrane separator, a mixed solution of complexing precipitation and a complexing agent is filtered and intercepted through a tube pass of the first membrane separator, and a filtrate enters other membrane separators through a shell pass of the first membrane separator to be subjected to multi-stage separation to obtain a membrane separation solution; performing pure crystallization on the membrane separation liquid; and centrifugally separating to obtain purified sodium fluoride, and drying the purified sodium fluoride to remove the residual solvent, thereby obtaining the high-purity sodium fluoride. According to the method, the content of cation impurities and the content of anion impurities in sodium fluoride are effectively reduced at the same time, high-purity sodium fluoride is obtained through a pure crystallization method, the centrifugal separation liquid, the complexing agent and the alcohol crystallizing agent can be recycled, and the purposes of high efficiency, environment friendliness and low cost of purification are achieved.

The disclosure relates to a process for separating a hydrocarbon-containing feedstock stream by extractive distillation, wherein the feedstock stream is contacted with a water-soluble solvent for aromatics in countercurrent. An aliphatics fraction is distillatively removed as aliphatics product stream from the mixture obtained. The aromatics are stripped from the aromatics-enriched solvent that remains and the aromatics-depleted solvent is recycled in a solvent circuit, with compounds having a lower boiling point compared to the solvent accumulating in the solvent circuit as impurities. At least a substream of the solvent circuit is purified for removal of the impurities, wherein the substream for the purifying is subjected to a thermal separation process, in which the impurities are at least partly discharged in a top product and the purified solvent that remains is recycled into the solvent circuit. An apparatus for carrying out the process is also disclosed.

According to the epoxypropane production system and method with the high conversion rate and the high yield, the interior of the reactor is divided into the upper section and the lower section through the production system, the accurate feeding proportion of three materials is provided, and the mode of segmented control and distributed feeding is provided; propylene and most of hydrogen peroxide diluted by a solvent are added into a first reaction section at the bottom through a first-stage feeding distributor for reaction, and then a reaction mixed solution of the residual solvent and hydrogen peroxide is supplemented into a second reaction section through a second-stage feeding distributor, so that reaction materials are uniformly mixed for reaction; the problem that the temperature is too high and hydrogen peroxide is decomposed due to uneven mixing caused by one-time adding or non-distributed adding of materials is avoided, the conversion rate of the materials is increased, meanwhile, fins are arranged on the outer sides of the catalytic tubes, the heat exchange area is increased, reaction heat is discharged in time, hydrogen peroxide decomposition is avoided, and the catalytic effect is improved. The selectivity and the yield of the product epoxypropane are further improved.

The invention relates to the technical field of liquid chromatographic analysis, and discloses a data acquisition method and system of a liquid chromatograph. The method comprises the following steps: extracting chromatograms without solvent residues and with known solvent residues from a historical database, and training by using a self-encoding neural network and a convolutional neural network to generate a baseline reference model and a ghost peak early warning model; obtaining solvent parameters of the previous analysis method, and calculating the residual solvent concentration through residual solvent information; inputting the residual solvent concentration into the baseline reference model and the ghost peak early warning model, and calculating to obtain a baseline drift prediction correction value and a ghost peak prediction risk area; pre-correcting the chromatographic signal acquired in real time to obtain a purified chromatographic signal; performing qualitative and quantitative analysis on the purification signal according to dynamic allocation resources of the ghost peak risk area to generate final chromatographic data; the data interference of the mobile phase residue is effectively eliminated, and the accuracy of data acquisition is improved.

The invention relates to a method for detecting residual solvent benzene in a ziprasidone hydrochloride bulk drug. According to the detection method, dimethyl sulfoxide is used as a diluent, a 2.8 mol / L potassium hydroxide solution is used as a cosolvent, and a dimethyl sulfoxide solution of high-concentration ziprasidone hydrochloride can be completely dissolved under a high-temperature heating condition, so that the sensitivity of benzene meets the requirement; and detecting the benzene in the ziprasidone hydrochloride bulk drug by using a gas chromatograph (GC-FID headspace sampling) connected with a hydrogen flame ionization detector. The detection method can be used for quantitatively detecting benzene higher than 0.4 ppm in ziprasidone hydrochloride bulk drugs. The method is high in sensitivity and practicability, and the detection process is simple and rapid.

The invention discloses a preparation method of a hole transport layer, a solar cell and an electric device thereof. The preparation method of the hole transport layer of the solar cell comprises the following steps: 1, sputtering a layer of NiOx film on the surface of conductive glass by adopting a magnetron sputtering method; 2, putting the NiOx thin film substrate into a mixed solution of water and hydrogen peroxide for ultrasonic cleaning, and then cleaning with ethanol to obtain a modified NiOx thin film; 3, the modified NiOx film substrate is put into a mixed solution of SAMs and ethyl alcohol to be subjected to ultrasonic cleaning, then ethyl alcohol is used for cleaning, and a modified NiOx film is obtained; and 4, drying the modified NiOx thin film substrate, eliminating the residual solvent, heating and annealing to obtain the hole transport layer. The hole transport layer prepared by the invention is more matched with the energy level of the perovskite layer, and hole transport is facilitated; and non-radiative recombination at the interface can be inhibited, and the extraction of current carriers is facilitated. The performance of the perovskite solar cell is effectively improved, and processing of large-area devices is facilitated.

The utility model relates to a washing, dewatering and drying device for resin particles. The washing, dewatering and drying device comprises a barrel, a filtering barrel, a spraying mechanism and a drying mechanism, and the barrel is provided with a feeding port and a drainage port; the filtering barrel is arranged in the barrel body so as to divide the interior of the barrel body into a material cavity located on the side, close to the feeding opening, of the filtering barrel and a water drainage cavity located on the side, close to the water drainage opening, of the filtering barrel; the spraying mechanism is arranged above the filtering barrel, and the drying mechanism is communicated with the material chamber. Resin particles can fall onto the filtering barrel through the feeding hole to realize dehydration; the spraying mechanism can be used for cleaning resin particles on the filtering barrel, residual solvents in the resin particles can be washed and leached out, and sewage can flow into the drainage cavity through the filtering holes and then is discharged to the outside through the drainage opening; the drying mechanism can dry resin particles in the material cavity, dewatering, cleaning and drying can be integrated, the problem that the resin particles are seriously rubbed can be avoided, the structure is simple, and the production efficiency can be improved.

The invention discloses a multilayer microencapsulated small molecule peptide liposome as well as a preparation method and application thereof. According to the invention, a'liposome-wall material 'double-embedding structure is formed by optimizing the phospholipid purity and compounding the hydrophilic wall material and the stabilizer, and a high-pressure homogenization and low-temperature spray drying combined process is adopted, so that the preparation process is green and environment-friendly. The obtained lipidosome has the characteristics of good fluidity, excellent sensory characteristics, high stability and the like, the solvent residue is far lower than the industrial standard, and the lipidosome can be widely applied to dosage forms such as tablets, capsules, solid beverages and the like. According to the technology, the production process is simplified, the use of toxic solvents is avoided, the bioavailability of the small molecule peptide is remarkably improved, and the problems of stability and production cost in industrial application are solved.

The invention discloses a preparation method of 2-hydroxy-4-(methylthio) butyric acid, and belongs to the technical field of chemical engineering, 2-hydroxy-4-(methylthio) butyronitrile and acidic resin are subjected to a hydration reaction and a hydrolysis reaction, then extractive distillation treatment is performed to recover an extraction agent, and the product 2-hydroxy-4-(methylthio) butyric acid is obtained; according to the invention, the acidic resin is used for replacing free acid, so that the corrosion to equipment is reduced, the possibility of side reaction between concentrated acid and 2-hydroxy-4-methylthio butyronitrile is avoided, the content of impurity polymers is obviously reduced, and the yield of a main product reaches 99.8% or above; the generated resin ammonium salt is about 50% less than the inorganic ammonium salt generated by using free acid, so that the post-treatment cost is reduced; through the process method provided by the invention, the prepared 2-hydroxy-4-methylthiobutyric acid is high in purity, the content of impurities such as residual solvent and resin ammonium salt in the product is low, and efficient separation and purification are realized.

The invention discloses a method for determining the content of various residual solvents in a clozapine bulk drug by using capillary gas chromatography, and belongs to the technical field of drug analysis. According to the method, a gas chromatographic method is adopted, a capillary chromatographic column with 6% of cyanopropyl phenyl-94% of dimethyl polysiloxane as a stationary liquid is adopted, an FID detector is adopted for detection, and the content of the residual solvent is calculated by peak area according to an external standard method; wherein the multiple residual solvents are methanol, ethanol, isopropanol, n-amyl alcohol, n-butyl alcohol and toluene. The method disclosed by the invention is good in specificity, good in linearity, reliable in accuracy and high in sensitivity; the gas chromatographic method can be used for rapidly, effectively, accurately and reliably separating and detecting the content of various residual solvents in the clozapine raw material medicine, the product quality of the clozapine raw material medicine is improved, and the medication safety of a patient is improved.

Provided are a method for producing a cellulose acylate film, which makes it possible to produce a film having a reduced amount of residual solvent and a reduced amount of elution with good productivity even in a case where the film is relatively thick; and a cellulose acylate film. A cellulose acylate film (23) is produced by a method for producing a cellulose acylate film, the method including a casting step of forming a cast film by casting a dope (14) containing a cellulose acylate (11), a sugar ester derivative, and a polyester having a weight-average molecular weight in a range of 50000 or more and 1000000 or less and represented by a specific formula on a support; and a peeling step of peeling the cast film from the support.

The invention relates to a method for detecting a residual solvent in a paeonol raw material. The method comprises the following steps: (1) preparing a reference solution; (2) preparing a test solution; and (3) respectively injecting the reference solution and the test solution into a gas chromatograph in a headspace sampling manner, and calculating the content of the residual solvent by peak area according to an external standard method. According to the method, the contents of seven residual solvents including methanol, ethanol, acetone, acetonitrile, dichloromethane, ethyl acetate and trichloromethane in the paeonol raw material or preparation can be detected at the same time, and the detection time and cost are greatly saved. Moreover, the method can be used for detecting residual solvents in paeonol extracted by different processes, and has the advantages of high practicability, simplicity in operation, high specificity, high accuracy, high precision and the like. Reference and basis are provided for revision of residual solvent inspection items in paeonol quality standards, the quality of raw material medicines is effectively improved, and clinical medication risks are reduced.

The invention belongs to the field of high polymer material synthesis, and provides a method for preparing polyphenylene sulfide from high-purity p-dichlorobenzene, which adopts the whole process design of pre-construction of a composite sulfur source intermediate, regulation and control of an end group controllable oligomerization polyphenylene sulfide intermediate, segmented polymerization of the high-purity p-dichlorobenzene and precise dehydration-washing-drying. The ultra-low impurity level of 0.05-0.25 wt% of burning residues of the polyphenylene sulfide product, the sodium ion content of 10-200 mg / kg and the chloride ion content of 10-500 mg / kg is achieved, and meanwhile the high-performance stability of the melting point of 270-300 DEG C, the gel fraction of 92-99 wt% and the water content of 0.01-0.20 wt% is kept. The problems of deep removal of inorganic ions and ash content, balance of gel fraction and processability and control of residual solvents in the traditional polyphenylene sulfide preparation process are solved, and the method has wide application value in the fields of high-performance engineering plastics, special fibers, electronic packaging materials and the like.

To provide a gravure or flexographic ink that is superior in temporal stability, blocking resistance, high-temperature laminate strength, and low residual solvent level.SOLUTION: A gravure or flexographic ink includes a urethane resin (A), wherein the breaking stress of the urethane resin (A), measured under the conditions defined below, is 10 MPa or more, and the viscosity of the urethane resin (A) at a liquid temperature of 25°C and a solid content of 30 mass%, measured in accordance with JIS K 7117-1, is 800 mPa s or more. (Stress measurement conditions) Tensile speed: 50 mm / min, Temperature: 25°C, Sample shape: thickness 0.3 mm, width 5 mm, length 20 mm.SELECTED DRAWING: None

The present invention provides a composition for improving skin elasticity, improving skin wrinkles, skin regeneration, anti-inflammation, wound healing or promoting wound healing, comprising catnip-derived exosomes as an active ingredient. The composition of the present invention is less likely to contain residual solvents and other impurities compared to conventional catnip hot water extracts, catnip solvent extracts and filtrates of such extracts, and has excellent effects of improving skin elasticity, improving skin wrinkles, skin regeneration, anti-inflammation, wound healing or promoting wound healing.

The invention relates to the field of PCB transfer, in particular to a transfer trolley for PCB production and processing. According to the transfer trolley, a closed space is formed by a sleeve shell and an electric control lifting cabin and used for preventing harmful chemical gas from leaking outwards, hot air flow is conveyed to all layers of PCBs through an air heater so as to accelerate volatilization of residual solvents and the harmful chemical gas, then volatile matter is pumped to an activated carbon layer through an exhaust fan to be adsorbed, and through the process, the residual solvents and the harmful chemical gas can be recycled. According to the PCB stacking device, the PCB residual solvent can be rapidly volatilized and harmful gas can be collected and treated synchronously in the transferring process, and in addition, the stacking operation of all PCBs in the electric control lifting cabin can be rapidly completed by pulling open the side supporting plates between the C-shaped inserting rails; the technical problem that each PCB transfer trolley needs to be parked for a long time to wait for a PCB to wait for volatilization of a residual solvent, and the use efficiency of the PCB transfer trolley is seriously affected is solved.

An analysis method for detecting multiple residual solvents during the preparation process of a drug. In the method, a gas chromatographic method is utilized to simultaneously detect 21 organic solvents, i.e. methanol, tetrahydrofuran, ethanol, cyclohexane, diethyl ether, isopropyl acetate, acetone, n-heptane, isopropanol, n-butyl alcohol, acetonitrile, dioxane, dichloromethane, pyridine, tert-butyl alcohol, toluene, tert-butyl methyl ether, N,N-dimethylformamide, n-hexane, dimethyl sulfoxide and ethyl acetate. The method is free from influence of drug types, can be applied to the content detection of multiple residual solvents in drugs, has simple operation and a wide usable range, and saves on the time and cost for drug detection.

The invention discloses a health food quality safety tracing system based on a block chain. According to the system, an optimization model taking health food quality risk assessment as a target is constructed; selecting the total number of bacterial colonies, the number of pathogenic bacteria, solvent residues, water activity, temperature, air pressure, granularity, mixing uniformity, effective component quantification, dissolution rate, residual oxygen amount and the like as core parameters, and constructing an optimized objective function; in addition, the system monitors and adjusts key parameters such as the temperature, the air pressure, the granularity and the residual oxygen content of the health-care food in real time through the AI driving module, and the food safety coefficient is improved; according to the invention, the conversion from passive supervision to active prevention is realized, the food qualification rate and the resource utilization rate are improved, and the method can be used for links of food production, transportation, sales and the like.