5291 results about "Acetonitriles" patented technology

The invention relates to a method for detecting the residual quantity of pesticides in a vegetable sample by utilizing a liquid chromatogram-high resolution mass spectrometer, which belongs to the technical field of a food safety detecting. The method provided by the invention comprises the following steps: 1) extracting the residual acetonitrile in the sample; 2) carrying out the dispersion solid-phase extraction and purification on a sample extraction solution; 3) detecting by utilizing the liquid chromatogram-high resolution mass spectrometer; and 4) analyzing the result. In the method provided by the invention, the quality accuracy of 27 pesticides is less than 1ppm; the detection limit is 0.01-0.05mg / kg; the addition recovery rate is 80-100%; and the relative standard deviation is less than 15%.

Application of a reference mixture of natural products for systematic analysis and comparison of the properties of biphasic solvent systems in counter-current / partition chromatography. Because the reference mixture is comprised of compounds with varying polarities, functional groups, and structural features it provides a rational method for mapping the optimal resolution polarity range of a particular solvent system. The mapping of optimal resolution polarity ranges of solvent systems provided for the description of the overall optimal resolution polarity range of a solvent system family, comprised of the same solvents in different proportions. By comparing the reference mixture performance in the individual members of a solvent system family, the solvent system that best functions as the representative of, or portal to, the solvent system families is determined. Use of the reference mixture also afforded a method to compare the overall optimal resolution polarity ranges of solvent system families. Based on performance of reference mixture chromatograms, the CCC properties of solvent systems, can be compared and their CCC potential examined. The methods of the invention employing the reference mixture provides was used to identify a quaternary solvent system, hexane / t-butylmethylether / acetonitrile / water (HterAcWat), which was found to be useful for CCC of mixtures containing natural products.

The invention relates to the fields of analytical chemistry and food safety, in particular to a method for detecting the residual quantity of multiple alkaline drugs in animal derived food. Based on the vortex mixed extracting of acetonitrile, isopropanol and citric acid buffer solutions, the purification of a hydrophilic polystyrene-divinylbenzene solid phase extraction column and a cation exchange solid phase extraction column and the liquid phase chromatography-mass spectra determination, the method can detect the residual quantity of multiple alkaline drugs in pork, pork liver, eggs, shrimps and milk, such as beta-receptor agonists,sulfonamides, benzodiazepines, nitroimidazoles, benzimidazoles and triphenylmethanes. The method has the advantages of simple operation, fast and accurate detection and high efficiency.

A combination therapy comprising a therapeutically-effective amount of an epoxy-steroidal aldosterone receptor antagonist and a therapeutically-effective amount of a calcium channel blocker is described for treatment of circulatory disorders, including cardiovascular disorders such as hypertension, congestive heart failure, cirrhosis and ascites. Preferred calcium channel blockers are those compounds having high potency and bioavailability. Preferred epoxy-steroidal aldosterone receptor antagonists are 20-spiroxane steroidal compounds characterized by the presence of a 9alpha,11alpha-substituted epoxy moiety. A preferred combination therapy includes the calcium channel blocker verapamil HCl (Benzenacetonitrile, (±)-alpha[3[[2-(3,4-dimethoxyphenyl) ethyl]methylamino]propyl]-3,4-dimethoxy-alpha-(1-methylethyl)hydrochloride) and the aldosterone receptor antagonist epoxymexrenone.

The invention relates to neutral mononuclear copper (I) complexes for emitting light and with a structure according to formula (A) in which: M represents: Cu(I); L∩L represents: a single, negatively charged, bidentate ligand; N∩N represents: a diimine ligand (substituted with R and FG), in particular a substituted 2,2′-bipyridine derivative (bpy) or a substituted 1,10-phenanthroline derivative (phen); R represents: at least one sterically demanding substituent for preventing the planarisation of the complex in the excited state; FG=functional group, and represents: at least one second substituent for increasing solubility in organic solvents. The substituent can also be used for electron transport or alternatively for hole transport, said functional group being bound to the diimine ligands either directly or by means of suitable bridges; and the copper (I) complex: having a ΔE(S1−T1) value of less than 2500 cm−1 between the lowest excited singlet state (S1) and the triplet state (T1) which lies below; having an emission lifespan of at most 20 μs; having an emission quantum yield of greater than 40%, and a solubility of at least 1 g / L in organic solvents, in particular polar organic hydrocarbons such as acetone, methyl ethyl ketone, benzene, toluene, chlorobenzene, dichlorobenzene, dichloromethane, chloroform, dichloroethane, tetrachloroethylene, alcohols, acetonitrile or water.

The invention provides a phosphorus-contained organic silicon resin fire retardant shown as a following formula and a preparation method thereof. The preparation method of the phosphorus-contained organic silicon resin fire retardant comprises the following steps: firstly, adopting polyalcohol and phosphorus oxychloride as raw materials to prepare chlorinated volution phosphoester; then carrying out hydrolytic condensation on amino-containing silane, dialkoxy silane and trialkoxysilane to obtain amino-containing organic silicon resin; finally dissolving the amino-containing organic silicon resin into a methylbenzene solvent, an N,N-dimethyl fomamide solvent or an acetonitrile solvent, and the like, and adding the chlorinated volution phosphoester and an acid-binding agent for synthesis to obtain the phosphorus-containing organic silicon resin fire retardant. The phosphorus-containing organic silicon resin fire retardant can be used as a fire retardant for polyolefin, makrolan, ABS, nylon and PC / ABS, has high efficiency and low toxicity compared with the traditional fire retardant and is an environmental protection type fire retardant for plastics. R1, R2, R3 and R4 are respectively selected from CH3 or C6H5, R5 is selected from CH2 or CH2CH2 or CH2CH2NHCH2CH2, and R6 is selected from the CH3 or C2H5; n is equal to integers of 1 subtracting 50, P is equal to integers of 1 subtracting 50, and q is equal to integers of 1 subtracting 50.

The invention discloses a redox graphene film, a preparation method and application thereof. The redox graphene film is prepared from the solution, which is formed by dissolving graphene oxide (GO) in polar solvent such as water, ethanol, methanol, acetone, acetonitrile, ethylene glycol, acetic acid, formic acid, ethyl acetate, pyridine, toluene and the like or mixed solvent thereof serving as a raw material, through steps of construction of a power-on repairing system, electron injection and the like. Compared with the resistance of the redox graphene film material before repairing, the resistance of the prepared redox graphene film is reduced by 102 to 108 times. The RGO film repaired by the method can be applied to the field of photoelectric conversion of the photoelectric response device and the like.

The invention relates to a blocking remover of a gas well shaft. The blocking remover comprises, by weight, 5-25% of an alcohol ether compound, 0.5-10% of a dispersant, 1-10% of a cleaning agent, and 0.5-5% of chelating agent, with the balance being a nitrogen-containing polar solvent, wherein the nitrogen-containing polar solvent is one selected from N,N dimethyl formamide, N,N dimethyl acetamide, and N-methyl pyrrolidone, the alcohol ether compound is one selected from glycol-ether, glycol-propyl ether, glycol-butyl ether, and diglycol-ether, the disperant whose micelle particle size is from 20nm to 100nm is a middle-phase microemulsion-type dispersant mixed by kerosene, water, a surfactant and a cosurfactant, the cleaning agent is one selected from allene diamine, acetonitrile and pentylamine, and the chelating agent is one selected from sodium citrate and EDTA. The blocking remover has the advantages that corrosivity is weak, that the speed of dissolving blockage is fast, that the product performance is stable in high temperatures, and that the blocking remover can reduce damages caused by water locking and fouling in areas close to gas wells, and can recover the permeability of storing layers.

The invention discloses a preparation method and the application of a catalytic material for transition metal carbides, belonging to the preparation technical field of the catalytic material. The invention is characterized in that in the method, carbon material, oxide or molecular sieve, and the like, are used as vectors and transition metal compounds are used as precursors. The vectors and the transition metal precursors are mixed by dipping or mechanical method and a microwave-assisted chemical sedimentation method is adopted to prepare the catalyst for loaded transition metal carbides. The weight percentage of loading of the transition metal compounds is 1-200 percent. Particles of the catalyst for the loaded transition metal carbides are highly uniformly distributed on the surface of the vectors. And the catalyst can be applied to a plurality of reactions of electrocatalysis oxidation of methanol, hydrazine decomposition, acetonitrile hydrogenation, etc. The preparation method and the application have the beneficial effects of simple preparation process and easy operation. And the obtained catalytic material shows high activity in the electrode reaction and a plurality of catalytic reactions of fuel cells.

A system for identifying Shenqi Fuzheng injection includes a mechanism for establishing a profile of a sample to be tested; a mechanism for establishing a characteristic fingerprint profile of Shenqi Fuzheng injection as a standard fingerprint profile; and a mechanism for comparing the profile of the sample to be tested with the standard fingerprint profile to distinguish between authentic Shenqi Fuzheng injection and counterfeit Shenqi Fuzheng injection.A method for establishing a Shenqi Fuzheng injection fingerprint spectrum, including: employing an ultra-high voltage liquid chromatography mass spectrometer to test the Shenqi Fuzheng injection, the chromatography conditions including: chromatographic column: Agilent Zorbax Eclipse Plus C18, 2.1 mm×100 mm, 1.8 μm; mobile phase: mobile phase A is 0.1% formic acid aqueous solution, and mobile phase B is 0.1% formic acid acetonitrile solution; and employing gradient elution procedure.

An apparatus for separating propane from propene by extracting-rectifying in a divided wall column (DWC) in which the water contained acetonitrile is used as the extractant is disclosed. Said DWC has a vertical bulkhead to divide it into three regions: the region A for extracting rectifying of propene and propane, the region B for separating propane from propene, and the region C as common desorption region. Its separation method is also disclosed.

A process for producing enantiomerically enriched (S)-α-(2-chlorophenyl)-6,7-dihydrothieno[3,2-c]pyridine-5 (4H)-acetic acid hydrocarbyl ester, represented by the formula: Is provided, wherein R1 and R2 are hydrogens and R3 is methyl (i.e., (S)-Clopidogrel). The process includes the steps of: (a) contacting N-2-chlorobenz-aldehyde-ylidene-1-ethylamine-2(2-thiophenyl)imine and an HCN source, in the presence of a non-metallic asymmetric Strecker catalyst to form enantiomerically enriched (S)-α,α-(2-thiophenylethylamino)(2-chlorophenyl)acetonitrile; (b) contacting the enantiomerically enriched (S)-α,α-(2-thiophenylethylamino)(2-chlorophenyl)acetonitrile and a formaldehyde equivalent, in the presence of an acid catalyst to form enantiomerically enriched α-5(4,5,6,7-tetrahydro[3,2-c]thienopyridyl)(2-chlorobenzyl)-nitrile; and (c) contacting the enantiomerically enriched α-5(4,5,6,7-tetrahydro[3,2-c]thienopyridyl)(2-chlorobenzyl)-nitrile and a reagent capable of converting a cyano group into an ester group to form enantiomerically enriched hydrocarbyl ester of (S)-α-(2-chlorophenyl)-6,7-dihydrothieno-[3,2-c]pyridine-5(4H)-acetic acid.

The invention discloses an analysis method for simultaneously measuring residues of 12 sulfonamide medicaments, 19 quinolone medicaments and 8 benzimidazole medicaments and metabolites thereof in chicken liver by quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and purification-ultrahigh performance liquid chromatography-tandem mass spectrometry (QuEChERS-UPLC-MS / MS). The method comprises the following steps of: extracting a sample by using 1 percent acetic acid-acetonitrile solution, purifying the sample by using NH2 adsorbent, and degreasing the sample by using n-hexane;and then performing separation by using a Kromasil Eternity C18 chromatographic column (100mm*2.1mm, 2.5mum), performing gradient elution by using 0.1 percent formic acid and methanol as mobile phases, performing ionization in an electron spray positive ion (ESI<+>) mode, performing detection in a multi-reaction monitoring (MRM) mode, and performing quantification by an internal standard method. The 39 medicaments have good linearity (r is more than 0.98) in a blank adding concentration range of 5 to 100mug / kg, the average recovery rate of the medicaments in the adding level range of 10 to 50mug / kg, the relative standard deviation (RSD) is 1.5 to 23.4 percent, the limit of detection (LOD) of the 39 medicaments is 5mug / kg, and the low limit of quantification (LOQ) is 10mug / kg. The method is simple, convenient, quick, sensitive, accurate and rugged, and is suitable for confirmation and quantitative determination of the residues of the residues of the sulfonamide, quinolone and benzimidazole medicaments in the chicken liver.

The invention relates to a method for detecting multiple residual solvents in a medicament. According to the method, by utilizing a gas chromatographic method, nine organic solvents including methanol, ethanol, acetonitrile, acetone, isopropanol, methylene dichloride, ethyl acetate, tetrahydrofuran and triethylamine in the medicament are simultaneously detected, the sensitivity and the precision are high, and the repeatability is good; by utilizing a standard addition method, other standard substances do not need to serve as internal standard substances, only pure substances of to-be-measured components are needed, the accuracy requirement on the sampling volume is low, and the operation is simple; by utilizing a headspace sampling method, a direct solution sample is prevented from interfering the detection and polluting a chromatographic column; by utilizing a temperature programming method, low-boiling-point organic solvents and high-boiling-point organic solvents can be effectively separated.

The invention discloses a single crystal graphene pn node and a preparation method thereof. The modulated and doped graphene pn node is prepared according to the method which comprises the following steps of 1, annealing a copper foil substrate; 2, growing a sub-monolayer intrinsic graphene island on the surface of a copper foil by taking methane as a carbon source; 3, cleaning a growing system by using inert gas; 4, taking acetonitrile steam as a nitrogen-containing carbon source and growing nitrogen doped graphene on the boundary of the intrinsic graphene island; 5, repeating the steps 2, to 4, for at least zero time to obtain the single-level or multi-level graphene pn node; 6, quickly reducing the temperature to stop a growing process; and 7, transferring the graphene pn node which is obtained through modulating, doping and growing onto any target substrate by using polymethyl methacrylate (PMMA) as a medium. The modulated and doped graphene pn node with high quality is obtained by regulating the carbon source in the graphene growing process. The product has very high migration rate and photon to current conversion efficiency; and a transfer characteristic curve of the product has a double-Dirac point, so that the single crystal graphene pn node can be applied to logic devices, such as a phase inverter and a frequency multiplier.

The invention relates to alkyl imidazole perrhenate ionic liquid and a method for preparing the same. The adopted technical proposal is follows: the preparation method comprises the following steps: taking certain volume of alkyl imidazole chloride compounds or alky imidazole bromide compounds, adding deionized water the volume of which is 2 to 4 times of that of the alkyl imidazole chloride compounds or the alky imidazole bromide compounds to dissolve the alkyl imidazole chloride compounds or the alky imidazole bromide compounds, adding the mixture to OH-type anion exchange resin to perform ion exchange, and collecting outflow solution which is alkyl imidazole hydroxide; then adding the alkyl imidazole hydroxide to ammonium perrhenate aqueous solution, wherein the molar ratio of the alkyl imidazole hydroxide to the high ammonium perrhenate is between 1 to 1 and 1 to 2, then stirring the mixture for 3 to 5 hours at a temperature of between 70 and 90 DEG C, reducing the pressure and distilling the mixture to remove water, adding the mixed solution of anhydrous methanol and acetonitrile to the mixture after cooling the mixture, sealing and stirring the mixture intensely, keeping stand the mixture for 10 to 15 hours at a temperature of between 30 DEG C below zero and 40 DEG C below zero, reducing the pressure and distilling the mixture to remove the methanol and the acetonitrile, and performing vacuum drying on the treated mixture. The ionic liquid prepared by the method has the advantages of high yield and high stabilities of air and water.

The invention relates to a method for continuously synthesizing arylboronic acid ester by utilizing a microreactor, which belongs to the technical field of green organic synthesis application. The method comprises the following steps of: preheating substituted arylamine, tert-butyl nitrite, bisdiborane in a continuous-flow micro-channel reactor system by using substituted arylamine, acetonitrile, tert-butyl nitrite and bisdiborane as starting materials; and mixing the substituted arylamine with the bisdiborane and then reacting the obtained mixture with the tert-butyl nitrite, wherein in the reaction, the molar ratio of the substituted arylamine to the bisdiborane is (1:0.5)-(1:1.25), the molar ratio of the substituted arylamine to isoamyl nitrite is (1:1.1)-(1:1.5), the reaction temperature is 60 DEG C-120 DEG C, the reaction time is 50 seconds-3600 seconds, and the effective conversion ratio of the substituted arylamine is 50%-90%. The continuous-flow microreactor, which is capable of strengthening the mixing effect, the mass transfer effect and the heat transfer effect, is especially suitable for carrying out homogeneous reaction of the method. Moreover, the method has the characteristics of stable temperature control, safe process and less waste material.

The invention relates to a method for simultaneously detecting multiple residual solvents in ceftriaxone sodium, which adopts a gas chromatographic analysis process to simultaneously detect six organic solvents in medicines, including methanol, ethanol, acetonitrile, acetone, ethyl acetate and triethylamine. The gas chromatographic process is adopted to simultaneously detect the contents of the six organic solvents, and has the advantages of high sensitivity, favorable repetitiveness and high precision; by using a standard addition process, the method does not need any additional standard substance as an internal standard, only needs a pure substance for predicting components, can counteract the matrix effect, and is simple to operate; by using a headspace sampling process, the method prevents the direct solution sample from interfering with detection and from polluting the chromatographic column; and a programmed heating process is adopted to effectively separate low-boiling-point organic solvents from high-boiling-point organic solvents.

The invention discloses a method for preparing high-purity acetonitrile from acetic acid and ammonia by two steps, which comprises the following steps of: (1) neutralizing acetic acid and ammonia to generate ammonium acetate; (2) mixing aqueous solution of ammonium acetate and gaseous ammonia, preheating, and making the mixture enter a fixed bed reactor filled with a catalyst aluminium oxide for reaction to generate acetonitrile-containing mixed gas; and (3) continuously refining the mixed gas to obtain the acetonitrile. The 70 to 80 weight percent acetic acid is taken as a raw material, and the produced acetonitrile product has the advantages of less varieties and low content of impurities, high purity of over 99.9 percent, simple separation process, shorter flow, low energy consumption only about 40 percent of that of a byproduct method in unit product, and lower cost. The separation process is a physical separation method, and avoids generating a great amount of wastewater and waste gas in the chemical treatment process of the byproduct method. Meanwhile, a synthesis method is adopted, so the limitation that the yield is limited by a main product can be radically eliminated.

The invention relates to a method for detecting eight volatile carbonyl compounds in a filter tip through liquid chromatography-tandem mass spectrometry. The eight volatile carbonyl compounds are formaldehyde, acetaldehyde, propanal, acetone, acraldehyde, crotonaldehyde, butanal and 2-butanone. The method comprises the following steps: performing ultrasonic extraction on the carbonyl compounds in a filter tip by using an acetonitrile / water mixed solution, performing 2,4-dinitrophenylhydrazine derivatization reaction, and analyzing through a liquid chromatography-tandem mass spectrometer (LC-MS / MS). Compared with the original gas chromatography, the LC-MS / MS method used in the method has the following advantages: (1) the LC-MS / MS method is higher in sensitivity, and the two-stage mass spectrometry can more effectively eliminate the false positive result, thus ensuring that the qualitative analysis accuracy is higher; (2) separation is performed through liquid chromatography, and 2,4-dinitrophenylhydrazone of the carbonyl compounds has favorable stability; (3) the sample does not need to be purified, and the pretreatment is simple and efficient; and (4) the method can realize the simultaneous detection of the eight volatile carbonyl compounds.

The invention discloses a pyridine quaternary ammonium salt type halamine antibacterial agent with a structure represented by a general formula I, wherein n is an integer of 1-10. The preparation method comprises the following steps: a, 5,5-dimethyl hydantoin is placed in an acetone solution doped with anhydrous potassium carbonate; refluxing is carried out for 30min, and dibromoalkane is added; refluxing is continued for 4h, such that a bromo-alkyl hydantoin compound is obtained; b, the obtained bromo-alkyl hydantoin compound is dissolved in acetonitrile; excessive pyridine is added; heating and refluxing are carried out overnight; concentration is carried out, such that a pyridine bromide quaternary ammonium salt type halamine precursor is obtained; the precursor is delivered through chlorine-type anion exchange resin, such that a pyridine chloride quaternary ammonium salt type halamine precursor is obtained; and c, the obtained pyridine chloride quaternary ammonium salt type halamine precursor is dissolved in a mixed solution composed of deionized water and tert-butanol; tert-butyl hypochlorite is added, and stirring is carried out for 2-4h while protected from light, such that the pyridine quaternary ammonium salt type halamine is obtained. The method has the advantages of easy-to-obtain raw materials, and relatively simple synthesis method. The method has a prospect of industrialized application.

The invention discloses a method for preparing an all-solid-state polymer electrolyte membrane and a prepared electrolyte membrane. The method comprises the following steps of: dissolving liquid crystal polymer E or F containing sulfoacid ions into N-methylpyrrolidone and acetonitrile to obtain a solution G; dissolving PEO (Poly Ethylene Oxide) into water and acetonitrile to obtain a solution H; dissolving PMMA (Polymethyl Methacrylate) and LiClO4 into an acetone solution to obtain a solution I; mixing G, H and I, evenly mixing, and pouring in a die; drying after volatilizing to form the membrane or manufacturing the membrane by a whirler; and obtaining a PEO / PMMA composite solid-state polymer electrolyte membrane containing the liquid crystal polymer and LiClO4, wherein the thickness range of the membrane is 0.2-0.5mm, and the room-temperature ion electrical conductivity of the membrane is above 10-3S / cm. The electrolyte membrane obtained through the technical scheme of the invention is the polymer solid electrolyte membrane product with favorable ion electrical conductivity and high mechanical strength.

The invention belongs to the field of Chinese medicine analysis and particularly relates to a content measurement method for Chinese patent medicine prepared from sweet wormwood, honeysuckle and gardenia jasminoides fruit. The method measures the content of nine ingredients including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, geniposide, secoxyloganin, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C in the Chinese patent medicine by reversed-phase high performance liquid chromatography, wherein the chromatographic conditions include: a chromatographic column is C18 column; methanol or acetonitrile is used as a flowing phase A; 0.05-to-1.0 percent phosphoric acid or 0.05-to-1.0 percent acetic acid is used a flowing phase B; the totalpercentage of flowing phases A and B is 100 percent; and gradient elute is performed. The content measurement method has high repeatability; and the method completely reflects the main ingredients and the change of the main ingredient content of the medicine from a qualitative prospect respectively and thus improves the level of the control over the quality of the medicine.

The invention relates to the fields of analytical chemistry and food safety, particular to a method for detecting the residual quantity of multiple polypeptide veterinary drugs in animal-derived foods. The method comprises the following steps of: processing a sample with a TCA(trichloroacetic acid) and acetonitrile system for depositing proteins; extracting with a carbinol and 0.1% formic acid aqueous solution system; purifying with a Oasis HLB solid phase extraction column; performing gradient elution with an Eclipse XDB-C18 analytical column in the presence of an acetonitrile and 0.1% formic acid aqueous solution used as a mobile phase; and then performing electrospray and positive ion scanning mode separation for finally detecting four polypeptides. The limits of the four polypeptides, namely colistin, bacitracin A, polymyxin B and virginiamycin M, are 25 micrograms / kilogram, 100 micrograms / kilogram, 250 micrograms / kilogram and 120 micrograms / kilogram respectively; the recovery rates of colistin, bacitracin A, polymyxin B and virginiamycin M are 74.9-88.1%, 76.2-89.0%, 76.6-81.2% and 77.3-86.9% respectively; and the coefficients of variation (CV%) of colistin, bacitracin A, polymyxin B and virginiamycin M are 5.7-15.1%, 7.2-15.7%, 6.0-8.0% and 9.5-18.6% respectively. The detection limit, the recovery rate, the accuracy and other technical indexes all meet related detection requirements at home and aboard.

The invention relates to 1-(1,2-epoxypropyl)-N-nitroimidazoline-2-amine which has a structural formula as shown in the picture. A preparation method of the compound comprises the steps of adding ethylenediamine to a reaction container, dropwise adding epoxy chloropropane in the reaction container while stirring, reacting for 2-3h, cooling, and vaporizing out acetonitrile to obtain epoxypropyl ethylenediamine; taking and dissolving nitroguanidine and the epoxypropyl ethylenediamine into water, dropwise adding hydrochloric acid solution while stirring, reacting for 2-3h, cooling, extracting, desolventizing to obtain crude product, and recrystallizating to obtain the product; or adding N-nitroimidazoline, potassium carbonate and organic solvent to the reaction container, heating to 75-81.6 DEG C, dropwise adding epoxy chloropropane in the reaction container after dissolving the N-nitroimidazoline, continuously heating until completing the reaction after dropwise adding, cooling reaction products, filtering, vaporizing filtrate to dry, adding water to residues, extracting by using methylene dichloride, desolventizing to obtain phase product, and recrystallizating by using butanone to obtain the product.

A detection method of a nitrofuran metabolites and chloramphenicol multiresidue in shrimp belongs to the technical field of aquatic products detection. The method is as below: hydrolyzing a sample with hydrochloric acid, subjecting nitrofuran metabolites to derivatization by using 2-nitrobenzaldehyde, adjusting the pH value to 6.5-7.5, adding acetonitrile, adding an extraction salt package; conducting liquid-liquid extraction of a target compound by using acetonitrile; purifying and concentrating a supernatant; then determining by a liquid chromatography-tandem mass spectrometer, and quantifying by an internal standard method. The method uses a novel sample extraction and purification mode for simultaneous analysis and determination of two prohibited drugs with the highest detection rate in shrimp, overcomes the limitations of separate determination of two drugs in the detection method of the prior art, improves the extraction efficiency of chloramphenicol in actual positive samples, greatly improves the work efficiency, shortens the work time and saves reagent consumption and labor costs. The method adopts the isotope internal standard method for quantification, the determination result is more accurate and reliable, has high sensitivity, and good reproducibility and quantitative accuracy.

The invention relates to a specific fluorescent probe for identifying hydrogen sulfide and an application of the probe, belonging to the field of fine chemical engineering. The fluorescent probe is a resorufin derivative. Resorufin sodium salt, potassium carbonate and 2, 4-binitro bromobenzene are mixed in proportion in acetonitrile liquor to be heated, and finally are purified by silica gel chromatography to obtain the fluorescent probe. The fluorescent probe and a corresponding hydrogen sulfide content detection process are not interfered by matrixes and impurities in a biosystem and can be used for quantitative determination of hydrogen sulfide content in various biosystems. The fluorescent probe has high specificity and can be hydrolyzed with hydrogen sulfide after being specifically cyclized to obtain a hydrolysate with broken ether bonds. The probe is low in cost and feasible, can be obtained by chemical synthesis and is simple and feasible in synthetic process. The probe is high in sensitivity, and has good fluorescence emission spectrum characteristics (600-650nm). In the wavelength range, the background fluorescence of a biological sample is weak, so that the probe is suitable for detecting hydrogen sulfide content in cells. Hydrogen sulfide is quantitively detected by drawing a standard curve.

The invention provides a method for rapid detection of multi-class pharmaceutical and personal care products and pesticides in water. The method includes: taking a to-be-detected water sample, and subjecting the to-be-detected water sample to pretreatment to obtain a to-be-detected sample; employing one or more groups of the following five groups of detection conditions for liquid chromatography-tandem mass spectrometry detection on the to-be-detected sample respectively so as to realize qualitative analysis and quantitative detection of multi-class pharmaceutical and personal care products and pesticides in the to-be-detected water sample: (a) the mobile phase is a formic acid-ammonium formate aqueous solution and acetonitrile, and the ionization mode is electrospray ionization positive mode; (b) the flow phase is a formic acid aqueous solution and acetonitrile, and the ionization mode is electrospray ionization positive mode; (c) the mobile phase is an acetic acid-ammonium acetate aqueous solution and acetonitrile, and the ionization mode is electrospray ionization negative mode; (d) the mobile phase is water and acetonitrile, and the ionization mode is electrospray ionization negative mode; and (e) the mobile phase is a formic acid-ammonium formate solution and acetonitrile, and the ionization mode is electrospray ionization positive mode.

The invention belongs to the technical field of productions of chemical products, in particular to a method for preparing 5-hydroxymethylfurfural. The method includes steps of taking a macromolecular polyphosphazene polymer matrix as a solid acid type heterogeneous catalyst, taking monosaccharide, disaccharide or polysaccharide as raw materials, reacting for 5minutes to 24 hours in single-component solvent or double-component solvent such as dimethyl sulfoxide, acetonitrile, methyl isobutyl ketone, water and the like at the temperature of 25-120 DEG C under normal pressure, and finally producing the 5-hydroxymethylfurfural efficiently. The method has the advantages that conversion efficiency of raw material is high, HMF selectivity is good, operation conditions are mild, reaction speed is high, the processing is simple and environment-friendly, the catalyst is easy to prepare and the like, corrosion to equipment and environment pollution due to common liquid strong-acid homogenous catalysts are avoided, and a new way is developed for preparing commodity chemicals and substitute fuels according to regenerative biological resources.