1520 results about "Rotary evaporator" patented technology

The invention discloses an extraction method and an extraction device for cannabidiol-enriched industrial hemp essential oil. By adopting devices such as a screening machine, an oven, a soaking tank, a rotary evaporator, an ultrasonic agitation tank, a butterfly centrifuge, a first climbing-film evaporator, a proportioning tank, a pressurized chromatography silica gel column, an eluate tank, a second climbing-film evaporator, a rotary evaporator, a finished product tank and a solvent recovery tank which are sequentially connected by virtue of pipelines, industrial hemps are stepwise subjected to the operation steps comprising screening, baking, extracting, re-treating, filtering, monitoring, sampling, chromatography and concentrating to obtain the finished product and the effective component cannabidiol-enriched industrial hemp essential oil is finally extracted. By virtue of the extraction device disclosed by the invention, the defects of low efficiency, large consumption and inconvenience in scale production of the conventional process are overcome, the semi-finished product containing tetrahydrocannabinol in the processing does not artificially contact and flow, is legal, safe and efficient, the process method is simple and can be easily promoted and the product has high purity, complete active ingredients and low cost.

A lipid of the pearl-hydrolyzed liquid used for cosmetics is prepared through adding antiseptic agent to the soybean lecithin, dissolving in chloroform solution, rotational evaporating in a bottle to become the dried soybean lecithin film, dissolving the pearl-hydrolyzed liquid in the mixture of bisodium hydrogen phosphate solution and sodium bihydrogen phosphate solution, regulating pH=7, slowly pouring it into said bottle containing the dried soybean lecithin film, oscillating for 3-6 hrs, and ultrasonic treatment.

The invention discloses a 4, 5-disubstituted-2-aminothiazole compound. The structural formula is shown in the specification, wherein R1 is 4-tolyl, 4-chlorophenyl, 4-methoxyphenyl, 4-nitrobenzene or propoxy, and R2 is phenyl, 4-tolyl, 4-fluorophenyl, 4-methoxyphenyl, 2-furyl, isopropyl, 4-nitrophenyl or n-propyl. The invention simultaneously provides a preparation method of the 4, 5-disubstituted-2-aminothiazole compound. The preparation method comprises the following steps: enabling an olefin azide type compound and potassium thiocyanate to react at the temperature of 75-85 DEG C in the presence of a solvent and a metal catalyst, concentrating an obtained reaction solution, then extracting with water and ethyl acetate, washing an obtained organic layer, then drying and concentrating by a rotary evaporator; performing silica gel column chromatography on an obtained concentrate to obtain the 4, 5-disubstituted-2-aminothiazole compound.

The invention relates to a preparation method of an amino polyether organic silicon compounded antifoaming agent. The method comprises the following technological steps: (1) adding allyl glycidyl ether and a platinum catalyst into a container, heating under stirring and reflux condensing conditions in the protection of N2, adding a toluene solution of hydrogen-containing silicone oil when the temperature rises to a certain level, after the reactions, removing the solvent and substances with low boiling points in a rotary evaporator, and drying so as to obtain epoxy modified silicone oil; (2) adding the epoxy modified silicon oil obtained in the step (1) and an ethanol solution of polyether amine into a container, heating under stirring, carrying out reactions under the reflux condensing conditions in the protection of N2, after the reactions, removing ethanol in a rotary evaporator, and drying so as to obtain amino polyether organic silicon; (3) compounding the amino polyether organic silicon obtained in the step (2) with a certain amount of silicone cream, a mixed emulsifier, and a thickening agent to prepare the amino polyether organic silicon compounded antifoaming agent. In the provided method, amino polyether organic silicon is prepared through a silicon-hydrogen addition / amination reaction and then is compounded with an emulsifier, a thickening agent, and silicon cream so as to prepare the amino polyether organic silicon compounded antifoaming agent, which can be dissolved in water quickly, has the advantages of excellent heat resistance, acid resistance, alkali resistance, and antifoaming property, and has the same performance as that of antifoaming agents in the market.

A rotary evaporator comprising a motor, a rotary joint movably inserted to a motor rotor of the motor by a sleeve in an axial direction, a collection flask attached to the rotary joint at one end of the joint, with a condenser attached to the other end of the joint. The condenser is adapted to receive a cooling coil from an immersion cooler. The cooling coil is attached to the base unit of the immersion cooler via an insulated hose. The rotary evaporator is adapted to provide various ways to remove heat from the flask in the water bath, whether by mechanically lowering the water bath, dropping fluid from the bath into an underlying reservoir, or raising and lowering the rotary evaporator out of the bath. Where the rotary evaporator is raised and lowered, the immersion cooler can remain in place if the hose connecting the base unit to the cooling coil is sufficiently long, or the condenser includes a flexible portion that accommodates the upward and downward movement.

The invention discloses the preparation of a compound polysaccharide humectant and application of the compound polysaccharide humectant to cigarettes. The preparation method comprises the following steps of: (1) crushing compound Chinese medicines such as Adenophora elata, dwarf lilyturf tuber, and platycodon grandiflorus, adding water, slightly boiling, performing reflux extraction, mixing extracting solution, and filtering; (2) adding protamex and high-temperature amylase into the extracting solution, and performing enzymolysis; (3) absorbing naturally cooled enzymolysis extracting solution by using a macroporous resin column, and collecting flow-through liquid; (4) concentrating the flow-through liquid in a rotary evaporator until the moisture is not evaporated to obtain the polysaccharide humectant; and (5) dissolving the polysaccharide humectant in water and adding into cut tobacco, wherein the humidification effect of cigarettes is remarkably improved, and the dry sensation of the cigarettes is reduced and the sweet degree of the cigarettes is strengthened when the cigarettes are smoked. The invention has the outstanding advantages that: the compound polysaccharide humectant can improve the aesthetic quality of the cigarettes, reduce the dry sensation of smoke, improve the sweet degree and comfort degree, and has remarkable effects of promoting the secretion of saliva or body fluid and humidifying; and the application of the technology cannot change the conventional cigarette processing technology, and the technology has actual application value.

The method for extracting alliin from garlic includes the following steps: boiling garlic by using water or microwave or acid solution to inactivate alliin being in garlic and obtain garlic pulp or garlic juice, diluting with water and adding pectase or cellulase or their mixture to make enzymolysis, after conventional disinfection treatment inoculating lactic acid bacteria to make fermentation, making fermented liquor pass through strong acidity cation-exchange column to make exchange, eluting with ammonia water to obtain eluent, concentrating by using rotary evaporator, adding ethyl alcohol, standing still and crystallizing to obtain white or helvolus crystal product, i.e. the invented alliin.

The invention discloses a method for detecting pyrethroid pesticide residue amount in smoke by a cigarette filter, belonging to the technical field of tobacco chemical analysis. The method comprises the following steps: placing a sucked filter tip at standard smoking condition into a 150ml of bottle with a tapered plug; adding 100mL of mixed solvent of ethyl acetate and cyclohexane with the volume ratio of 1:1; placing the bottle on an ultrasonic wave generator for extraction for 30min; concentrating to be 0.5mL on a rotary evaporator after drying by anhydrous sodium sulfate; setting the volume to be 2mL by normal hexane to be purified; placing a small graphite carbon black column on a solid phase extractor; activating by 3mL of acetone and 3mL of normal hexane in sequence; transforming the sample test solution to be purified into the small graphite carbon black column; eluting for two times by utilizing 2.5mL of mixed solvent of acetone and normal hexane, wherein the speed does not exceed 5.0mL / min; evaporating and concentrating eluent; setting the volume to be 1.5mL by acetone and normal hexane with the volume ratio of 2:8; and analyzing on GC-ECD. The method of the invention is simple and accurate, and can effectively determine pyrethroid pesticide residue amount in smoke by the cigarette filter.

The present invention relates to the technical field of aromatic plant cell water extraction, and provides an aromatic plant rose cell water extraction method, wherein roses are placed in a rotary evaporator, rotary dry distillation is performed to form steam, and condensation is performed to obtain the condensate. Compared to other static vacuum dry distillation methods, the method of the present invention has the following characteristics that the rotary evaporator is used to perform dry distillation without the water adding, such that the heating is uniform, the distillation temperature is low, the distillation time is short, and the distillation efficiency is high. According to the present invention, after the roses are subjected to dry distillation dewatering, the obtained aromatic plant rose cell water has characteristics of full top note, long fragrance lasting time, simple process, mild fragrance, fragrance close to natural rose aroma, and no flocculent precipitate generation, and can be used as the raw material for production of food, cosmetics and health products; the dried rose collected after the dry distillation has bright color, does not generate yellowing or browning, and is slightly different from the color and the aroma of fresh rose so as to substantially ensure the quality; and the process is simple, the energy consumption is substantially reduced compared to the existing method, and the characteristics of environmental protection and low cost are provided.

The invention relates to a liquid chromatography for detecting anabolic hormone drug residue in animal-derived food, which is characterized by first sampling: animal musculature is taken off the fat and connective tissue, then minced and evenly ground, and the sample is weighed; extracting: anabolic hormone extract is extracted from the weighed sample by methanol ultrasonic extraction, the extract is evaporated to dryness in water bath through a rotary evaporator, and the residue is dissolved by methanol aqueous solution; purifying: C18 Solidoid extraction column on the extract is carried out solid phase extraction; and testing by devices: the filtrate is tested by opposite phase high efficiency liquid chromatography, quantified by external reference method-peak area, and then carried out with binary gradient elution. In the invention, the detected sample is complex biological sample; the established method can complete one detection in about one hour and is simple and fast, with reliable sensitivity and low cost; the method can analyze more veterinary hormone drug species than the synchronous usage of the existing GC or HPLC methods with easier operation, and has lower cost than the existing GC / MS and LC / MS or LC / MS / MS methods with low solvent toxicity.

The invention provides an extraction and purification method of cordycepin from Cordyceps militaris, and belongs to the deep-processing technical field of agricultural products. The method comprises the following steps: crushing Cordyceps militaris raw material, mixing the raw material with water at 1:20 raw material / water ratio, performing ultrasonic extraction, and performing centrifugal filtration on obtained extracting solution and pouring in a macroporous resin column at the adsorption flow of 1.8BV / hr; taking 15% methanol aqueous solution as an eluant to perform resin column elution, and decompressing and condensing obtained eluent at the temperature of 60 DEG C by a rotary evaporator to obtain Cordyceps militaris cordycepin concentrate. The method can help realize aqueous solution extraction of the cordycepin from the Cordyceps militaris raw material at low temperature, and the extraction rate reaches 85%; and polysaccharide and protein can be removed from the extract by macroporous resin separation and purification, thus the content of the cordycepin in the extract can reach 10%. The cordycepin in the Cordyceps militaris product has high activity, can be taken as a raw material for producing cordycepin monomer and can also be directly taken as an additive of health products and functional food, thus the cordycepin has wide market development prospect.

The invention discloses a method for preparing bio-oil through supercritical pyrolysis of civil sludge. The method comprises the steps of: directly putting sludge from a factory into a high-pressure sealed reaction vessel, and repeatedly purging to achieve inert atmosphere by adopting nitrogen gas; enabling water in the sludge as a raw material in the reaction vessel to reach a supercritical state through temperature programming and pressurization by nitrogen gas, so as to realize pyrolytic reaction of the sludge in the supercritical water; and obtaining pyrolyzed bio-oil after vacuum filtration, liquid separation, extraction and rotary evaporation of a reaction product. A disposal system adopting the method ,mainly comprises a sequencing batch type high-pressure sealed reaction vessel, a booster pump, a condenser, a rotary evaporator, vacuum pump and the like. By adopting the invention, the links of drying and dewatering of sludge in the conventional oil-making technology through low-temperature sludge pyrolysis are avoided, the problem of use of a great amount of catalysts in direct liquefaction and oiling technologies of sludge are broken through, at the same time, the problem of secondary pollution of heavy metal is also avoided, and the bio-oil with high added value can be obtained.

The invention relates to a method for preparing bisphenol-A liquid epoxy resin, and belongs to the field of high polymer preparation. The method comprises the following steps: 1) adding a quaternary ammonium salt phase-transfer catalyst, and performing etherification at a temperature of between 70 and 85 DEG C for 45 to 240 minutes; 2) at a constant temperature of between 60 and 70DEG C, droppingalkali by NaOH aqueous solution for 1.5 to 4 hours, keeping epoxy chloropropane refluxing in the alkali dropping period, and discharging water out of a reaction system; and 3) separating unreacted epoxy chloropropane by a rotary evaporator at a temperature of 135DEG C, dissolving a mixture of resin and salt, removing solid salt by a filter, washing the resin for 3 to 5 times by water, separating solvent, and obtaining the final product. The prepared epoxy resin has the epoxy value between 0.55 and 0.56 through titration by hydrochloric acid acetone solution, low viscosity (between 7,000 and 10,000mPas), and the epoxy index between 0.595 and 0.622 through infrared spectroscopic analysis, and comprises 91 to 92 percent of micro molecular epoxy resin.

The invention relates to a grape fresh-keeping method using seaweed polysaccharide. The method is as below: cleaning and cutting a raw material of fresh seaweeds, conducting high speed tissue homogenate, leaching with 5-6 times of ethanol with concentration of 65-85% for 8-10 h, conducting pumping filtration, transferring to a rotary evaporator to obtain a seaweed polysaccharide crude extract, extracting the crude extract with 4-6 times of anhydrous ether, and concentrating an aqueous layer by using the rotary evaporator to obtain the seaweed polysaccharide; eliminating pests on fresh grapes and mechanically damaged fruits, soaking the grapes at room temperature in the seaweed polysaccharide solution for 5 min, drying, and packaging with a polyethylene film for storage; and inspecting regularly during storage, and eliminating abnormal fruits timely. The invention has the beneficial that natural seaweed polysaccharide as a protective agent for fresh-keeping of grape is safe, non-toxic and harmless, and can replace chemical fungicides and preservatives for fresh-keeping of grapes, and avoid the problems of environmental pollution and food safety caused by chemical fungicide.

The invention extends the utility of apparatus used to extract medicinal cannabis compounds into an eluate by separating a portion of medicinal cannabis compounds contained within a portion of eluate at a first extraction target level providing enough clean solvent to continue extraction operations. A high efficiency concentrator such as a rotary evaporator or a wiped film evaporator processes eluate from one or more tanks or extraction vessels creating clean solvent when extraction targets are met or when clean solvent is exhausted. This manages eluate concentration levels and limits the quantity of concentrated medicinal cannabis compounds on site at any moment in time. The invention enables a business model for keeping medicinal cannabis compounds within a legal system, and reduces pollution because law enforcement would no longer have to burn large quantities of cannabis plant matter.

A method for synthesizing cyclic carbonate by the catalysis of amino functional ionic liquid relates to a method for synthesizing the cyclic carbonate, in particular to a method for synthesizing the cyclic carbonate through a cycloaddition reaction between carbon dioxide and an epoxy compound. The invention aims at solving the problems of difficult carbon dioxide activation, low catalyst activity, use of a toxic organic solvent and strict reaction conditions of the existing method for synthesizing the cyclic carbonate through the utilization of the CO2 and the epoxy compound. The method comprises the following steps: using the amino functional ionic liquid as a catalyst, subjecting the epoxy compound and the CO2 to the reaction at a certain temperature and under certain pressure, utilizing a rotating evaporimeter to carry out pressure reduction and distillation on a reaction product, and obtaining the cyclic carbonate. The cyclic carbonate is mainly synthesized through the catalysis of the amino functional ionic liquid.

The invention discloses a technology for the steam explosion treatment of a yellow wood fruit and the comprehensive utilization of grease and flavone thereof, and the like. In the method, the yellow wood fruit is firstly arranged in a steam explosion reactor and is pumped with saturated steam for treatment for 3 to 10 minutes under the pressure condition of 1.4MPa to 2.0MPa; then the mixture is quickly discharged from the reactor for explosion; a blank obtained through the steam explosion is naturally dried or arranged in a drying box for drying; an organic solvent is added for reflux extraction; a rotary evaporator is used for decompressing and evaporation; the solvent is recycled, thus obtaining the oil of the yellow wood fruit. An ethanol liquid is added into the oil meal and then a flavone liquid is obtained through reflux extraction. The remainder after extracting the grease and the flavone are manufactured into active carbon through thermal treatment, thus realizing the comprehensive utilization of the yellow wood fruit.

The invention relates to a clean diesel pour point depressant and a preparation method thereof. The clean diesel pour point depressant is composed of long carbon chain fatty acid, low-carbon alcohol and low-carbon acid. The preparation method comprises the following concrete steps: weighing oleic acid by weight; adding glycerol, and carrying out heating under stirring until the oleic acid and the glycerol are dissolved; measuring the rate of esterification through an acid-base titration method; after a period of time, adding methacrylic acid, carrying out caustic washing and alcohol washing, then removing water through a rotary evaporator, and carrying out drying in an oven so as to obtain a target product namely methacrylic acid-glyceryl monooleate. According to the invention, by adopting an additive-free solvent and a catalyst, materials are economical, and cleanness and environment protection are realized. The pour point depressant provided by the invention has a formula applicable to good improvement of fluidity of diesel at a low temperature, and specifically meets the requirements of a diesel engine for clean and environment-friendly combustion tail gas emission in the process of diesel combustion.

The invention relates to a preparation method of an aminopolyether modified polysiloxane deforming agent. The preparation method comprises the following steps of: (1) adding allyl glycidyl ether and a platinum catalyst to a container, stirring and heating under the conditions of nitrogen protection and reflux condensing; after heating to a certain temperature, dropwise adding a toluene solution containing hydrogen silicon oil; at the end of reaction, removing a solvent and low-boiling-point substances on a rotary evaporator and drying to obtain epoxy modified silicon oil; and (2) adding the epoxy modified silicon oil obtained in the step (1) and an ethanol solution of polyether amine to the container, heating and stirring, reacting under the conditions of nitrogen protection and reflux condensing; at the end of the reaction, removing ethanol on the rotary evaporator and drying to obtain the aminopolyether modified polysiloxane product. According to the preparation method, hydrosilylation / ring opening amination is used, simultaneously amino groups and polyether chain segments are introduced to a polysiloxane skeleton, the obtained deforming agent has good water solubility and stability, no additives and compounding are not added, and the aminopolyether modified polysiloxane deforming agent has good defoaming and foam inhibition performances at normal temperature.

The invention relates to water-based transparent super-amphiphobic nano-paint and a preparation method and application thereof. Under the room temperature condition, hydrophilic silica nanoparticles and tetraethoxysilane or carbon tetrachloride serve as raw materials to synthesize oily nanoparticles with the concentration of 1-10 mg / mL; the oily nanoparticles and fluorocarbon resin are compounded according to the volume ratio of 1:1, a rotary evaporator is utilized for rotary evaporation for 30-60 min under the condition of a water bath at the temperature of 60-90 DEG C, and high-solid-content oily nano-paint concentrated liquor with the concentration of 20-40 mg / mL is obtained; water and surfactant are added, and the water-based transparent nano-paint with the super-amphiphobic surface is obtained. The prepared paint is soluble in water, the preparation process is simple, and the paint is suitable for large-area spraying, is high in adaptability to a base material and transparency, good in protective performance, environmentally friendly and capable of improving the working environment, and saves energy.

A preparation method of a fluorescent carbon quantum dot probe for detecting beryllium in water comprises the following steps: preparing a citric acid solution with a concentration of 0.04 g / ml; weighing urea, adding the urea into the above citric acid solution, uniformly stirring to obtain a mixed solution, wherein the urea concentration is 0.01-0.04 g / ml; transferring the above mixed solution into a hydro-thermal reaction vessel, reacting at 200-240 DEG C, naturally cooling the reaction vessel to room temperature to obtain a brown aqueous solution; performing centrifugation by a centrifuge and dialysis in order of the brown aqueous solution, then concentrating the brown aqueous solution by a rotary evaporator, and finally drying in a vacuum drying oven to obtain a solid viscous substance. The product of the invention makes use of the fluorescence characteristic of carbon quantum dots; detection of beryllium ion content is carried out by a fluorescence spectrophotometer, which is low in cost; the sample preparation and treatment steps are simple and easy to operate; the detection selectivity and sensitivity are high; the product of the invention is widely applicable to beryllium ion detection.

The invention provides a method for preparing olystyrene hollow microspheres with high degree of sphericity. The method comprises the following steps of a, dissolving a polystyrene polymer and an additive in an organic solvent to obtain an oil phase; b, dissolving polyvinyl alcohol and anhydrous calcium chloride in distilled water to obtain an outer water phase; c, respectively injecting distilled water, the oil phase and the outer water phase into an inner water phase pipeline, an oil phase pipeline and an outer water phase pipeline in an axial emulsifiable granule generator by virtue of an injection pump and reacting to obtain distilled-water-in-oil-phase compound emulsifiable granules; d, collecting the compound emulsifiable granules in a rotary bottle in which the outer water phase is contained, placing in a rotary evaporator, heating in a water bath for curing; and e, cleaning the cured microspheres with distilled water, drying the microspheres in a drying oven to obtain the hollow microspheres with high degree of sphericity. The method disclosed by the invention is suitable for X-ray-driven symmetry research, laser inertial confinement fusion physical experiments and high-energy physical experiments.

The invention relates to a plant extract deodorant, in particular to a deodorant using orange peel or shaddock peel as an extracting source. The preparation method comprises the following steps of: cleaning orange peel or shaddock peel, crushing the orange peel or shaddock peel for 30-60 min by using a crusher, adding distilled water, and immersing the crushed orange peel or shaddock for 60-90 min; boiling the solution for 30-60 min, filtering out the decoction, adding distilled water into filter residue, decocting the mixture for 30 min, and merging the filtrates of two times; centrifuging the mixture at 2500-3000 r / min for 20-30 min, taking the supernate, and heating and concentrating the extract to obtain 100% concentration plant extract deodorant by using a rotary evaporator at constant temperature of 60 DEG C. The plant extract is diluted according to different needs. The plant extract deodorant provided by the invention has the characteristics of good deodorization effect, rapid effect taking and no secondary pollution.

An apparatus and method for recovering atmospheric moisture is disclosed utilizing the blade system of a wind turbine to both drive the compressor of a rotary refrigeration system and to provide a rotary turbo-machinery surface for its evaporator; whereon atmospheric moisture is recovered by reducing the temperature and pressure of the driving humid air. The rotational speed of the wind turbine is then used to maximize the rate of condensation; which is continuously centrifuged out from the rotary frame of blades into a stationary circular gutter where they accumulate and discharge. In the practice of this invention, a compressor with a rotary intake & discharge port is directly connected to a rotary evaporator & rotary condenser, generating a rotary refrigeration system wherein pressure of the liquid refrigerant is enhanced by the centrifugal force of rotation, enhancing the refrigeration capacity and condensation output.

The invention discloses a method of simultaneously determining contents of 1-OHP ,3-OHB[a]P and 3-OHB[a]A in urine. The method comprises sequentially using beta-glucuronidase for enzymatic hydrolysis of samples, performing solid-phase extraction and purification, concentrating the samples with a vacuum rotary evaporator, and determining by using a liquid chromatography-tandem mass spectrometer, thereby rapidly, accurately and simultaneously detecting contents of 1-hydroxy pyrene (1-OHP), 3-hydroxy benzo [a] pyrene (3-OHB [a] P) and 3-hydroxy benzo [a] anthracene (3-OHB [a] A) in the urine. The method uses deuterated standards as quantitative analysis substances of internal standards and thus can reduce errors in a pretreatment process for the samples; uses a tandem mass spectrometer to relatively improve selectivity and accuracy of the method; and selects a method of preparing standards by matrices, wherein, compared with a method of preparing the standards by pure water, the method of preparing standards by matrices is relatively good in accuracy and can eliminate interference from matrix effects. Through selecting and optimizing chromatographic columns and gradient elution conditions, the method relatively improves a chromatogram separating process and shortens a chromatographic analysis time.

The invention relates to a synthetic method for short-chain hydroxyl silicone oil. Firstly, the materials are proportionally measured according to raw materials components, then adding acid clay, water, and cyclotetrasiloxanes to a three-mouth flask with a reflux device, adding concentrated sulfuric acid in agitation condition, and reacting by controlling the reaction temperature, when the reaction is completed, adding magnesia and agitating about 10 minutes, then processing pumping filtration, distilling and recovering acetone using a rotary evaporimeter used for filtrating under the temperature of 45 DEG C, then adding sodium carbonate solution for neutralization under controllable temperature for stratification; then watering and washing the organic layer on the upper layer once or twice, then discharging water through stratification, and then feeding the organic layer into the rotary evaporimeter for warming up to 95 DEG C, depressing and detracting low-boiling residues, obtaining micromolecule hydroxyl silicone oil. The synthetic method for short-chain hydroxyl silicone oil has the advantages of simple technological process, easy controllable reaction condition, low cost and easily available raw materials, fast reaction generating speed, good product quality and high reactivity, and wide application range.

The invention provides a method for detecting pesticide residue in a white paeony root crude drug, comprising the following steps of: extracting powder of the white paeony root crude drug with acetonitril in oscillation, then, performing dispersed purification by using N-propyl ethylene diamine as a dispersion purifying agent and using anhydrous magnesium sulfate as a drying agent; evaporating solvent of the extract to dry at 40 DEG C in a rotary evaporators; and taking liquid chromatogram as a separation means and taking mass spectrum as a detection means after dissolving the residual again. The method provided by the invention can simultaneously detect 23 kinds of pesticide residues of organic chloride, organic phosphor and organic nitrogen types. By using the method provided by the invention to analyze the pesticide residue in the white paeony root crude drug, the sample is simply and conveniently processed, rate of recovery is high, and universality is high, so that the method has better application prospect.

The invention discloses a preparation method of a monoatomic catalyst for indoor air purification. The preparation method comprises the following steps of (a) performing preparation to obtain a yellow solid powder CeO2 carrier; (b) dissolving RuCl3.3H2O into deionized water to obtain dipping liquid, wherein the mass concentration of ruthenium in the dipping liquid is 5 to 50 mg / mL; and (c) preparing the monoatomic catalyst: adding the CeO2 carrier obtained by the step (a) into the dipping liquid obtained by the step (b) by a dipping method, adding an iodoform solution dissolved into glycol, mixing uniformly, dipping, drying the dipped solution on a rotary evaporator and calcining to finally obtain the monoatomic catalyst Ru / CeO2. By the method, the general catalytic reaction dosage (the load capacity is very low) is extremely small, and the atom utilization rate is extremely high.

The invention discloses a C-3-site aryl-seleno substituent coumarin compound and a preparation method thereof, and a novel method for establishing C-3-site aryl-seleno substituent coumarin by directlyperforming selenium modification on a substituent coumarin C-3-site C-H bond under a visible accelerant condition. The method comprises the following steps: firstly dissolving C-4-site arylamine substituent coumarin compound and diaryl diseleno ether compound in an organic solvent, then adding an oxidant persulfate, magnetically stirring and reacting for 18 to 30 hours under an air and room temperature condition and the illumination of a blue LED light source; and after the reaction is ended, removing the solvent of a reaction solution by virtue of a rotary evaporator, purifying a residue byusing a silica gel column, and preparing the C-3-site aryl-seleno substituent coumarin compound of a general formula (I).

The invention relates to a rotary evaporator comprising a rotary drive having a hub and a clamping insert with a sleeve-like basic shape, in particular a clamping sleeve, for the clamping of a steam leadthrough formed as a hollow glass shaft in the hub of the rotary drive, wherein the clamping insert has a longitudinal axis and a first and a second axial end, wherein the clamping insert has two clamping sections which are arranged spaced apart from one another in the longitudinal direction and which each have an outer cross-section tapering toward the first end and of which the clamping arrangement arranged closer to the second end has a larger maximum outer cross-section.