88 results about "Enrichment factor" patented technology

The invention discloses a method for simultaneously detecting six types of 24 antibiotics in water by solid phase extraction-liquid chromatography-tandem mass spectrometry. The method comprises (1) carrying out water sample pretreatment through adding an internal standard substance indicating a recovery rate before solid phase extraction, (2) enriching and purifying a target antibiotic with a solid phase extraction small column and (3) detecting contents of six types of 24 antibiotics in water through a liquid chromatography-tandom mass spectrometer. The method can simultaneously detect residues of six types of 24 antibiotics in water, has low time consumption in detection and has the advantages of high precision, high sensitivity, high stability, high selectivity and low detection limit.In the water sample pretreatment, an organic reagent use amount is small, environmental friendliness is realized, operation is simple, an enrichment factor is high and reproducibility is good. The method utilizes the internal standard substance indicating a recovery rate before solid phase extraction, well shows the loss of the target substances in the pretreatment and produces a real and reliablefinal result.

The invention discloses a method for simultaneously detecting six types of 24 antibiotics in livestock excrements by combination of ultrasonic extraction-solid phase extraction pretreatment and a liquid chromatography-mass spectrometry technology. The method comprises the following steps: (1) adding an internal standard substance for indicating the recycling rate in advance, and performing ultrasonic extraction; (2) performing solid phase extraction to enrich and purify target antibiotics; (3) performing the liquid chromatography-mass spectrometry technology to detect the contents of the 24 antibiotics. According to the method, the residue conditions of the six types of 24 antibiotics in the livestock excrements can be simultaneously detected at one time; the time of the detection processis short, the detection precision is high, the sensitivity, the stability and the selectivity are high, and the detection limit is low; by optimization of an extraction solvent, chelation between theantibiotics and metal ions in the excrements can be effectively reduced, so that the target antibiotics are separated from a sample, and the recycling rate is increased; furthermore, the method is easy and convenient to operate, high in enrichment factor and high in repetitiveness. The internal standard substance for indicating the recycling rate is added before the whole pretreatment process, sothat the loss of target substances in the pretreatment process can be well expressed, and a final result is more real and reliable.

The invention provides a preparation method and an application of a COF (covalent organic framework) material. The COF material is formed by repeating units shown in the description; the COF materialhas excellent chemical and thermal stability, large specific surface area and high crystallinity, and higher enrichment factor and lower detection limit are obtained when the COF material is used forenriching and detecting phenol. According to the provided preparation method of the COF material, all that is needed is to conduct a reaction at room temperature, and reaction conditions are mild.

The invention discloses a method for simultaneously detecting the medicaments such as furazolidone, diazepam, trimethoprim, acetaminophen and ibuprofen in water. The method comprises the following steps of: filtering a water sample to remove suspended matter; adjusting the pH of the water sample to be 2 to 4; activating hydrophile-lipophile balance (HLB) solid phase extraction column by using acetone, methanol, ammonium acetate-containing formic acid aqueous solution and ultrapure water in sequence; after the enrichment is finished, drying the HLB solid phase extraction column under the protection of nitrogen and eluting the HLB solid phase extraction column; collecting eluant, and drying the eluant by blowing a nitrogen flow; adding acetonitrile to dissolve the residue; and quantitatively detecting the concentration of the five medicaments. By the method, the water sample pretreatment is environment-friendly, easy to operate, large in enrichment factor, and high in reproducibility; and the content of the five common medicaments in a water environment can be analyzed quickly and accurately.

The invention discloses a modified-chitosan and graphite oxide magnetic nano absorbent and a preparation and application of the modified-chitosan and graphite oxide magnetic nano absorbent, and belongs to the field of absorbing material preparation. By the adoption of a one-step thermal solvent method, functional monomer chitosan and graphite oxide are directly added to a magnetic source environment with the high-temperature and high-pressure conditions, and a solid-phase extraction material is formed in a synthesis mode. The synthesis method is simple, the process is easy to control, a great number of functional groups of the graphite oxide and chitosan are combined, the absorbent has excellent absorption function, firm in bonding, stable in property, good in ruggedness, larger in enrichment factor, capable of being used in a wider PH value range and suitable for enrichment pretreatment of trace amount Cu (II) in the environmental water sample.

A preparation method of a pervaporation metal organic framework UiO-66 series gasoline desulfurization film includes: introducing a zirconia sol layer firmly combined with a carrier onto the carrier to obtain the carrier with the zirconia sol layer, and performing solvothermal growing to prepare a film layer; in the process of growing, the zirconia sol layer provides a metal source for a Uio-66 series film and serves as a active site and a connection point of film forming to promote forming of the UiO-66 series film which is continuous, uniform and complete. The UiO-66 series film prepared bythe method is a hydrophilic film and can preferentially adsorb thiophene with relatively high polarity; zirconium in a framework of the UiO-66 series film has special adsorption effect on thiophene, so that the UiO-66 series film has excellent performance in pervaporation dulsufurization, enrichment factor is higher than 10, and permeation flux is greater than 1.0kgm-2h-1. In addition, UiO-66 series materials are comparatively stable, so that the obtained film can be operated continuously for a long time (longer than 3d) while maintains stable performance.

The invention relates to a method for recycling sulphur from a sulphur-containing residue. The method comprises the following steps: mixing the sulphur-containing residue and an organic solvent in a proportion; heating, preserving heat, and stirring to melt the sulphur; keeping the temperature of a mixture and filtering; drying a filtered residue, and recycling the organic solvent; settling and layering a filtrate; returning the organic solvent on the upper layer into a system for reuse; cooling liquid sulphur on the lower layer to obtain finished sulphur. The method disclosed by the invention is simple in equipment, low in investment and energy consumption, high in sulphur recycling rate and low in residue amount; the sulphur content in the residue is low; the valuable metal enrichment factor is large; continuous production is convenient to realize.

The invention provides a technology and a device for removing heavy metal ions in electroplating wastewater, and belongs to the electroplating wastewater treatment technology. The continuous electrodeionization technology is employed to remove heavy metal ions with low concentrations in a solution and recyle the metal ions, which plays an important role in environmental protection. The metal ions which go into a membrane stack are transferred towards the direction of a cathode 8, penetrate a membrane 9, and go into a concentration chamber 13. The metal ions are subjected to enrichment in cyclic concentrated water, and as time goes by, high enrichment factor and high removal efficiency can be obtained. The device can remove and enrich single heavy metal ion or mixed heavy metal ions in waste water continuously, and has advantages of low energy consumption, minimal environment pollution and the like.

The invention relates to a chlorophenol graphene-based molecularly imprinted solid-phase extraction column, which comprises an empty column, a sieve plate and a filling material. The filling material is formed by mixing chlorophenol graphene molecularly imprinted nanoparticles and a conventional solid-phase extraction packing at the mass ratio of 1: 1-10. According to the chlorophenol graphene molecularly imprinted nanoparticles, a magnetic Fe3O4 high-molecular material is supported on the surface of graphene as a function unit, and a target chlorophenol compound to be adsorbed is used as template molecule. Meanwhile, the invention also relates to a preparation method and an application of the chlorophenol graphene-based molecularly imprinted solid-phase extraction column. The chlorophenol graphene-based molecularly imprinted solid-phase extraction column has large specific surface area, many adsorption sites, strong specific selectivity and good enrichment effect, can be used in enrichment of residual trace amount of chlorophenol compounds in an environmental water sample, and can achieve high enrichment factor and can remarkably reduce matrix effects. Meanwhile, the preparation method of the molecularly imprinted solid-phase extraction column is simple, technological conditions are stable, and production cost is low.

Disclosed is a method for determining nanoplastics based on cloud point extraction-thermal cracking gas chromatography mass spectrometry. The method comprises the following steps of: performing cloudpoint extraction on a to-be-determined solution under optimized cloud point extraction conditions, achieving nearly 500-fold enrichment of trace amounts of nanoplastics in water, and maintaining original morphologies and particle sizes of the nanoplastics by using the method; and removing TX-45 in a surfactant phase by using a heating decomposition method after the enrichment by the cloud point extraction, and realizing composition identification and quality determination of the nanoplastics by using a Py-GC/MS method. The method is simple in operation steps and good in stability, the interference of the sample matrix is small, the enrichment factor is high, and the separation and determination of trace amount of nanoplastics in the actual water can be realized.

The invention discloses a method for evaluating a minimum area of a line profile error of a cross section of a skirt part of a variable-ellipse piston. The method comprises the following steps of: measuring and acquiring a coordinate of a measurement point on the cross section of the skirt part of the variable-ellipse piston at first, if the coordinate of the measurement point is a rectangular coordinate, converting the rectangular coordinate into a polar coordinate, and establishing a model for evaluating the minimum area of the line profile error of the cross section of the skirt part of the variable-ellipse piston; then randomly producing an initial position and an initial speed of a particle, calculating a target function value of the particle according to the initial position of the particle and a measured value of the cross section line profile, and determining a partial optimal particle and a whole optimal particle; and modifying the speed of the particle and changing the position of the particle by an enrichment factor method, updating the position of the particle optimal particle and the position of the whole optimal particle by using the changed position of the particle, and when a predetermined terminating condition is achieved, outputting a minimum area answer, the optimal parameter value and the ovality of the line profile error of the cross section of the skirt part of the variable-ellipse piston. By the method, the minimum area answer, the optimal parameter value and the ovality of the line profile error of the cross section of the skirt part of the variable-ellipse piston can be calculated at the same time.

The present invention provides a method for manufacturing a composite membrane for gasoline desulfurization. The composite membrane is manufactured by compounding an epidermal layer membrane material and a support layer membrane material. The epidermal layer membrane material is polyethylene glycol or polyethylene oxide, which has strong permselectivity of sulfide in the gasoline; the support layer adopts a sodium polyimide filter membrane or an ultrafiltration membrane with temperature resistance and organic solvent resistance, which can resist complicated components of the gasoline and 150 DEG C high temperature. Adopting the appropriate composite membrane preparation can prepare a composite membrane with ultrathin epidermal layer and no defect which can resist high temperature and hydrocarbon. The composite membrane can be used to for gasoline desulfurization. Under the condition of 110 DEG C feeding temperature and 1.5KPa membrane posterior pressure, the sulfur enrichment factor of the prepared composite membrane for the gasoline with 1000 Mu g/g sulfur content is larger than 4 and the permeation flux is larger than 40kg.Mu m /m< 2 >h.

The invention belongs to the technical field of separation, and discloses a membrane for desorbing CO2 from a solution containing CO2 and a preparation method of the membrane. The membrane for desorbing CO2 from the solution containing CO2 comprises a base membrane and a polydimethylsiloxane membrane with an active group, wherein the active group is an ester group or an amino group; the thickness of the polydimethylsiloxane membrane is 10-70 microns. The preparation method comprises the following steps: mixing the polydimethylsiloxane and an active crosslinking agent, coating the mixture on the base membrane, and crosslinking and curing at a certain temperature to form the membrane. According to the membrane for desorbing CO2 from the solution containing CO2, the solution absorbing CO2 is one of methanol, acetone, polyethylene glycol dimethyl ether, propylene carbonate, dimethyl carbonate, diethyl carbonate and butyl succinate; the permeation flux of the membrane is up to 0.2-1.1 kg/(h*m2), and the enrichment factor is up to 23-50.

The invention relates to a method for separating and enriching chlorogenic acid in tobacco. According to the method, the chlorogenic acid in tobacco is separated and enriched by utilizing a solvent flotation technology, and a mixed organic solvent is added to serve as an extracting agent, so that the polarity of the extracting agent is changed, and the extraction rate of the chlorogenic acid is improved. The pH value of a tobacco extracting solution is regulated, so that the polarity of the extracting agent is matched with that of the chlorogenic acid, and the separation, enrichment and purification effect is good. The extraction can be performed at room temperature due to the adopted solvent flotation technology, and the operation conditions are mild. According to floatation of an air floatation solvent, an emulsification phenomenon generated due to shaking during common liquid-liquid extraction is avoided, the amount of the used organic solvent is small, and the method is large in enrichment factor, short in phase separation time, low in cost and feasible to operate.

The invention provides a method for enriching and detecting low-concentration phenol effective components. The method comprises the following steps: by taking a chitosan-multiwalled carbon nanotube dispersion liquid as an adsorbent, carrying out extraction-adsorption on a to be-detected sample liquid containing the low-concentration phenol effective components; then, eluting by using an eluent, wherein the eluent is the enriched sample liquid; detecting the enriched sample liquid by using liquid chromatograph/mass spectrometer and quantifying through a standard curve and an enrichment factor to detect the concentration of the phenol effective components in the be-detected sample liquid. The method provided by the invention can be used for detecting the low-concentration phenol effective components in a chrysanthemum diluent.

The invention discloses a surface soil heavy metal pollution source quantitative identification method based on enrichment factor value calculation. The method is characterized by collecting area surface soil and bottom background soil, and measuring a heavy metal content value; calculating an enrichment factor value of surface soil heavy metal; carrying out principal component analysis based on the enrichment factor value and qualitatively identifying a main pollution source of the surface soil heavy metal; taking a standardized total heavy metal enrichment factor value as a dependent variable, and taking different component loads of principal component analysis as an independent variable to establish a multiple linear regression equation; and according to a coefficient of a regression equation, quantitatively identifying relative pollution contribution rates of different source components of the area surface soil heavy metal. The relative pollution contribution rates of the differentsource components are accurately, effectively and quantitatively identified.

The invention provides a method for recovering phosphorus and rare earth from a rare earth-containing phosphate ore; the method comprises the steps: step S1, leaching the rare earth phosphate ore with a solution containing phosphoric acid, to obtain acid-leached slag and a leached solution containing rare earth ions, Ca<2+> and H2PO<4->; and step S2, carrying out aging treatment of the leached solution to obtain a rare earth phosphate precipitate, and making rare earth separated from Ca<2+> and H2PO<4->, wherein a reaction temperature of the step S2 is higher than a reaction temperature of the step S1. The method adopts the solution containing phosphoric acid for acid leaching of the rare earth phosphate ore at relatively low reaction temperature, phosphorus and rare earth elements are allowed to enter the leached solution, then aging treatment of the leached solution is carried out at relatively high temperature, the rare earth ions are allowed to form the rare earth phosphate precipitate, rare earth and phosphorus are separated and recovered efficiently, the rare earth enrichment factor is high, and further recycling is facilitated.

The invention discloses a gas phase chromatography-mass spectrometry detection method of polyoxyethylene nonyl phenyl ether in water, belonging to the technical field of water environment pollutant detection. The detection method comprises the steps of membrane filtration, pre-purification, solid phase extraction, enrichment and elution and comprises the following concrete steps: using an organicsolvent to extract the eluent which is specially treated chemically; then carrying out the gas phase chromatography-mass spectrometry detection of the organic phase; comparing the detection result with the standard curve to quantitatively obtain the concentration value of the polyoxyethylene nonyl phenyl ether. The invention has the advantages of simple pretreatment, easy operation, wide linear range, high enrichment factor, better reproducibility and accurate qualitative determination, has no need of adopting expensive liquid phase chromatography-mass spectrometry analyzers, and can quickly analyze the concentration of the polyoxyethylene nonyl phenyl ether in water.

The invention provides a method for enrichment and detection of low concentration anthraquinone effective components, the method uses Fe3O4 magnetic graphene (rGO @ Fe3O4) as an adsorbent for extraction and adsorption of a to-be-detected low concentration sample solution, then uses a desorption agent for elution, a solid obtained by drying of the eluant is dissolved, with a dissolution agent to obtain an enrichment sample liquid, the enrichment sample liquid is detected by a liquid chromatograph/mass spectrometer, and the concentration of the anthraquinone effective components in the concentration anthraquinone effective components can be detected by a standard curve and the enrichment factor quantitation. The method can be used for the detection of the low concentration anthraquinone effective components in a rhubarb medicinal material dilution and a biological sample a rat urine sample).

The invention relates to an application of nano magnesium titanate used as a solid-phase extraction adsorption medium in heavy metal ion enrichment, which is characterized by sucking a sample liquid with a syringe, adjusting the pH value to more than 5 with ammonia water, passing through a solid-phase extraction column at a flow rate v not larger than 20 mL/min, washing the column with 50 mL of water, eluting the analyte with 5-10mL of 2 moL/L nitric acid, collecting in a test tube and detecting the content of heavy metal ions in the eluate with an AAS (atomic absorption spectrophotometer) or ICP (inductively coupled plasma) method. The invention uses nano magnesium titanate as a solid-phase extraction adsorption medium to apply in heavy metal ion enrichment, has the advantages of low cost, large adsorption capacity, high enrichment factor, stable enrichment performance, good strong acid, strong base and organic solvent resistance, good high-temperature resistance and reusability, and can simultaneously enrich Pb, Cd, Zn, Cu, Ni and other heavy metal ions.

The invention discloses a method for enriching noble metals from a high-sulfur material. The noble metals are enriched through extracting base metals such as sulfur, nickel and copper from the high-sulfur material. Specifically the method comprises the following steps: fully grinding and uniformly mixing the high-sulfur material containing the noble metals, sodium salt, calcium salt, sodium hydroxide and lime in a ball mill; filling air in a rotary kiln to perform oxidation roasting on a mixture; adding hydrochloric acid into a roasted material to selectively leach out the base metals in the roasted material; adding the sodium salt and the lime into a leaching liquid, filtering and washing to obtain noble metal enrichment, wherein the enrichment factor is 14-20 times and the noble metals are not dispersed. The method has the advantages of simplicity, high enrichment factor, low cost, environment friendliness, high noble metal yield and the like, and has a better industrialization prospect.

The methods described allow for reducing particulate emissions from a direction injection engine during a starting phase, while also maintaining the engine start phase within a predetermined threshold. In one particular example, the methods comprise adjusting at least one of a fuel release pressure threshold and enrichment factor based on an engine condition; activating a starting device to rotate a crankshaft coupled to an engine cylinder without injecting any fuel; supplying fuel to the cylinder based on the enrichment factor only when a fuel pressure exceeds the fuel release pressure threshold; and stratifying a cylinder charge while adjusting a fuel injection within a compression phase and/or expansion phase of the engine. In this way, an amount of fuel injected may be evaporated in the combustion chamber while preventing a combustion wall wetting, which allows for reduced particulate emissions, particularly at reduced temperatures.

The invention relates to a high-permeation flux polydimethylsiloxane porous-wall micro-capsule hybrid membrane and a preparation method. The preparation method comprises the following steps of: preparing a DA-Ti hybrid porous-wall micro-capsule by using a template method and the process of biological mineralization in a restricted space; dissolving polydimethylsiloxane with a certain mass ratio in normal heptane at room temperature so as to form a homogeneous solution, and then adding the DA-Ti hybrid porous-wall micro-capsule into the solution; stirring and dispersing the suspension liquid; then adding a certain quantity of crosslinking agent and catalyst, and stirring, standing and defoaming to obtain a membrane casting solution; and then casting the membrane casting solution on a dry polysulfone basic membrane, and drying and treating to obtain the membrane. The hybrid membrane is used for simulating gasoline desulfurization, the enrichment factor of the thiophene is 4.29 to 5.89, and the permeation flux is 1.90 to 8.09 kg/(m<2>h). The preparation conditions of the hybrid membrane are mild, and raw materials are abundant and controllable.

The invention discloses a preparation method of a bisphenol A solid phase extractant based on dummy template covalently imprinted silica gel. The preparation method comprises the following steps: taking bisphenol-AF (BPAF) as the dummy template molecule and (3-isocyanatopropyl)-triethoxysilane (ICPTES) as the functional monomer to synthesize a novel monomer/template composite substance BPAF-Si; taking P-123 as the pore forming agent, carrying out condensation reactions between BPAF-Si and tetraethoxysilane (TEOS) to obtain silica gel containing a template, and heating to remove the template molecules which are covalently combined so as to obtain the covalently imprinted mesoporous silica gel namely the bisphenol A solid phase extractant. The bisphenol solid phase extractant has a very high selectivity recognizing performance on the template molecule BPAF, also has a similar selectivity recognizing performance on structural analogue such as BPA, is capable of nearly completely absorb trace BPA in a water solution, has a high enrichment factor, and can be repeatedly used. So the mesoporous imprinted silica gel is advantageously used as a novel solid phase extractant for the high selective enrichment and separation of trace BPA in an environmental sample.