193 results about "Microwave digestion" patented technology

The invention discloses a method for detecting glufosinate-ammonium residues in coffee in dual modes of colorimetry and chemiluminescence, and belongs to the technical field of chemical analysis and detection.The method comprises the steps that Schiff base formed by 4-aminoantipyrine and glutaraldehyde serves as a complexing agent of Cu < 2 + >, and then a copper-doped carbon dot Cu-CDs nano-enzyme is prepared through microwave digestion; according to the present invention, the Cu-CDs nano-enzyme has excellent peroxidase-like activity, can oxidize the colorless 2, 2 '-biazo-bis-3-ethylbenzothiazoline-6-sulfonic acid into the blue-green oxidized ABTS, and can improve the chemiluminescence intensity of the reaction of N-(4-aminobutyl)-N-ethylisoluminol and H2O2 by nearly 100 times when the Cu-CDs nano-enzyme is used as the chemiluminescence catalyst; based on the inhibition effect of glufosinate-ammonium on the activity of Cu-CDs POD, a sensitive and rapid colorimetric and chemiluminescence two-channel GM detection technology is developed, and the method has potential application value in the aspect of coffee safety monitoring.

The invention relates to the technical field of total phosphorus detection, in particular to a method for determining total phosphorus in water, which comprises the following steps: 1) digestion treatment: adding an oxidant into a water sample to be detected, and then performing microwave digestion treatment to obtain digested water; a molybdate reagent is added into the digested water, then an improved ascorbic acid solution is added, a chromogenic reaction is completed at the set temperature, and the improved ascorbic acid solution is obtained by mixing an ascorbic acid solution and sodium ethylene diamine tetracetate; measuring the concentration: measuring the absorbance value of the obtained color development product by using a spectrophotometer and a long-optical-path cuvette; and drawing a standard curve: using a phosphorus standard solution as a quality control sample, adding a plurality of calibration points in a low-concentration interval of 0.0-0.1 mg / L, carrying out colorimetric determination, and establishing quadratic equation fitting according to absorbance and concentration so as to determine the total phosphorus content of the water sample to be detected, and the method has the advantages of high sensitivity and good accuracy in total phosphorus testing.

The invention belongs to the field of solid waste recycling, and relates to a hematite modified rice hull-based biochar material as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out ultrasonic treatment on rice husks in an ethanol solution, then soaking the treated rice husks in a mixed solution of methanol and formalin for activation, carrying out vacuum filtration and drying, and carrying out anaerobic calcination under the protection of a nitrogen atmosphere to obtain rice husk-based biochar; the method comprises the following steps: soaking rice husk-based biochar in an acid solution, and carrying out microwave digestion on the acid-modified rice husk-based biochar to obtain chemically-modified rice husk-based biochar; adding into a solution containing ferrous sulfate, fully stirring, and then carrying out hydrothermal treatment to obtain the hematite modified rice hull based biochar material. The method can significantly improve the conversion rate of organic matters in the sludge, increase the accumulated yield of biogas, effectively reduce the biotoxicity of heavy metals in the sludge, facilitate the resource utilization of the sludge, and have important significance for solving the environmental risk problem of the sludge.

The invention relates to the technical field of microwave digestion instruments, in particular to a microwave digestion instrument with a pressure relief mechanism, which comprises a digestion instrument cabinet body, a digestion tank, an exhaust bracket disc, a pressure relief purifier, a ventilator, a power conversion tool and a disc gear, the peculiar smell can be timely absorbed by the L-shaped flat pipe after being exhausted from the digestion tank, so that the situation that the peculiar smell is diffused to pollute the microwave heating chamber is avoided, and compared with the traditional technology that the peculiar smell can be blown away without space dead angles by large-area ventilation in the microwave heating chamber, the positioning type peculiar smell absorption mode disclosed by the invention is lower in energy consumption and capable of rapidly exhausting the peculiar smell; a row of tanks filled with a purifying agent are used for absorbing and treating peculiar smell airflow, the peculiar smell airflow passes through one tank, the internal purifying agent is gradually saturated and loses efficacy when absorbing and treating peculiar smell, and before the efficacy loses efficacy, a path of the conveyed peculiar smell airflow is automatically replaced, and a new tank is selected for injection, which is equivalent to timely replacement of purifying liquid.

The invention discloses a microwave digestion-liquid flash spectrometer strontium isotope rapid detection system for multiple types of samples. The automatic sample injection module automatically identifies, grabs and conveys a sample by means of an image and radio frequency identification technology. The microwave digestion module is provided with a self-adaptive program, temperature and pressure are dynamically regulated and controlled through a PID algorithm according to sample characteristics, and efficient and safe digestion is ensured. The automatic separation and purification module intelligently selects a solid-phase extraction column or an ion exchange resin column to purify a sample by matching spectral analysis with a database. The liquid flash spectrometer detection module accurately collects signals by means of a high-sensitivity element and an algorithm. The data processing and control system adopts a multi-layer perceptron neural network, so that the strontium isotope content can be intelligently judged, and the source of abnormal data can be traced. In addition, the system has the functions of automatic cleaning and maintenance, emergency detection flow and remote monitoring, all the modules are connected through standardized interfaces, and the expansibility is high. The system is high in automation degree and accurate in detection, and an efficient and reliable scheme is provided for strontium isotope detection.

The invention discloses a microwave digestion tank with a rapid pressure reduction structure, and relates to the technical field of microwave digestion tanks. The microwave digestion tank with the rapid pressure reduction structure comprises a tank body and a tank cover, a mounting cavity is formed in the tank cover, a through hole is formed in the bottom of the mounting cavity, and an exhaust pipe is fixedly connected to the top of the through hole. According to the microwave digestion tank with the rapid pressure reduction structure, during rapid pressure reduction, when high-pressure gas in the sealing cavity is discharged through the through hole, gas-liquid separation, gas discharge and liquid return into the sealing cavity can be performed through the gas-liquid separation device, so that the liquid in the tank body is prevented from being taken out by gas flow, and the accuracy of a detection result is ensured.

The invention belongs to the technical field of chemical detection, and particularly relates to a method for detecting the content of boron in soil and sediment, which comprises the following detection methods: S1, weighing a sample and putting the sample into a digestion tank; s2, adding a digestion solution into the digestion tank; s3, after uniform stirring, putting the digestion tank into a microwave digestion instrument for microwave digestion; s4, after digestion is completed, closing the microwave digestion instrument, and after the digestion tank is cooled to the room temperature, filtering to remove precipitates; s5, transferring the digestion solution into a volumetric flask, and fixing the volume for subsequent analysis; and S6, analyzing the digestion solution by using ICP-OES / MS (Inductively Coupled Plasma-Optical Emission According to the method for detecting the boron content in the soil and the sediment, ammonium fluoride is used for replacing hydrofluoric acid in boron detection of the soil and the sediment, use of toxic reagents is reduced, mannitol is added, a stable complex is formed by mannitol and boron, and the recovery rate of boron is increased.

The utility model discloses a microwave digestion device for food detection and relates to the technical field of food detection. A suspension is fixed at the top in the digestion chamber, an inner gear ring is horizontally fixed at the lower end of the suspension, the digestion tank shaking support comprises a rotating cap, a digestion tank carrying disc and an assembly connecting rod, the rotating cap covers the rotating driving head, an eccentric groove is formed in the side of the rotating cap, the digestion tank carrying disc is obliquely arranged, and a shaft rod is arranged on the lower surface of the digestion tank carrying disc and rotationally inserted into the eccentric groove; the assembly connecting rod is coaxially arranged at the top of the digestion tank carrying disc, the top end is connected with the upper end of the suspension through a spherical hinge, the bottom end is provided with an elastic connecting plug which is detachably connected with a transmission connecting groove preset in the digestion tank carrying disc, and the middle section of the assembly connecting rod is provided with rolling teeth meshed with the inner gear ring. The digestion tank shake-up support is in an inclined form, the top of the digestion tank shake-up support is connected through a spherical hinge, the digestion tank carrying disc rotates in a conical surface and rotates at the same time, and effective shake-up action can be carried out so as to improve the digestion efficiency.

The invention relates to a digestion method for lithium sulfide impurity element analysis and a content determination method thereof, the digestion method comprises the following steps: (A1) pre-digestion: weighing a lithium sulfide sample, and adding ultrapure water to obtain a sample aqueous solution; dropwise adding oxidizing acid into the sample aqueous solution, and heating to enable the lithium sulfide sample in the sample aqueous solution to fully react, so as to obtain a pre-digested sample; (A2) microwave digestion: carrying out microwave digestion on the pre-digested sample under a closed condition to obtain a microwave digested sample, and fixing the volume to obtain a to-be-detected sample solution. Compared with a conventional multi-time acid-adding digestion method, the digestion method has the advantages that oxidizing acid does not need to be added repeatedly, so that the operation steps are simple, the digestion time is short, and compared with the multi-time acid-adding digestion method, the method can meet quantitative analysis of most impurity elements in lithium sulfide.

The invention provides a method for detecting the content of elements in carbonized resin. The method comprises the steps of resin pretreatment, instrument tuning, standard curve drawing, sample detection and the like. The method comprises the following steps: firstly, transferring a certain amount of dry carbonized resin into a cleaned PFA digestion tank, adding high-purity mixed acid, setting a segmented heating program to start microwave digestion, cooling to room temperature after digestion is completed, adding a proper amount of ultrapure water to dilute a digestion solution, and adding an internal standard solution and a chemical additive to obtain a to-be-detected sample solution; preparing a multi-element mixed standard solution according to the sample element types, adding the standard solution into the sample solution, and measuring the signal intensity ratio R of the to-be-measured element to the internal standard in each solution; and drawing a standard curve by taking the labeling concentration as a horizontal coordinate and R as a vertical coordinate, correcting the standard curve, and detecting the sample to be detected. The method is used for detecting the content of elements in carbonized resin, the carbonized resin is digested through microwaves, and the obtained solution is clear and can be directly subjected to ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometer) detection.

The invention discloses a method for determining the platinum content in a solid superacid catalyst based on ICP-OES and application of the method, and relates to the technical field of analytical chemistry, the method comprises the following steps: grinding a solid superacid catalyst sample into powder, mixing the powder with ZrO2, and digesting by adopting a microwave digestion method to obtain a digestion solution; carrying out cooling and acid removal on the digestion solution to obtain a solution to be detected; the wavelength of an analysis line of Pt is selected to be 265.945 nm, a standard solution is prepared through a matrix matching method, and a calibration curve is drawn. The method effectively overcomes spectral interference and physical interference of high-concentration ZrO2 and Al2O3 matrixes, has the characteristics of high sensitivity, good repeatability (RSD is less than or equal to 1.8%), standard recovery rate (97-101%) and high accuracy, and is suitable for industrial quality control and performance evaluation of the Pt-containing composite superacid catalyst.

This invention discloses a method for dissolving NiCrPSi nickel alloy samples for ICP-OES detection, comprising the following steps: mixing the NiCrPSi nickel alloy sample to be tested with hydrochloric acid aqueous solution, concentrated nitric acid, and hydrofluoric acid aqueous solution, digesting at 120-140℃ for 1.5-2.5h, and then evaporating the solution to dryness at 220-260℃; then adding nitric acid aqueous solution and heating until the solid is completely dissolved, and then diluting with water to obtain the NiCrPSi nickel alloy test solution. The dissolution method of this invention can completely dissolve NiCrPSi nickel alloy powder without elemental loss, providing an accurate sample solution for ICP-OES detection; and it eliminates the need for specialized equipment such as microwave digesters or electrothermal digesters, as well as special reagents such as perchloric acid and tartaric acid, using only conventional acid reagents and general experimental equipment, thus reducing costs, simplifying operation, and enhancing versatility.

The invention belongs to the field of detection, and particularly relates to a method for detecting the migration amount of nine metals in a cosmetic packaging material and application of the method. The method comprises the following steps: sample acquisition: taking cosmetic simulation liquid; sample migration; sample pretreatment: taking the cosmetic simulation liquid in the packing material, and respectively carrying out the following treatments: filtering the acid-containing cosmetic simulation liquid through a filter membrane; heating the alcohol-containing cosmetic simulation liquid to be nearly dry, fixing the volume by using nitric acid, and filtering; adding nitric acid into the oil-containing cosmetic simulation liquid, heating for pre-digestion, cooling to room temperature after the pre-digestion is completed, carrying out microwave digestion, heating until no yellow smoke is generated after the digestion is completed, fixing the volume by using deionized water, and filtering; an ICP-MS instrument is adopted for testing, and data acquisition and processing are carried out; and preparing a standard solution, and calculating to obtain the content of each element. Nine elements can be detected at the same time, and the detection efficiency can be effectively improved; the pretreatment method is designed for different cosmetic simulation liquids, and the detection accuracy can be improved.

The invention relates to the technical field of analysis and detection, in particular to a method for analyzing an aluminum element in peanut iodized oil. The analysis method specifically comprises the following steps: sample pretreatment: fully reacting a to-be-detected sample with nitric acid, treating the to-be-detected sample in a water bath environment at 80-120 DEG C for 1-2 hours, and then carrying out microwave digestion; after the digestion is completed, treating in a water bath environment at 60-80 DEG C for 1-2 hours, and fixing the volume. Performing inductively coupled plasma mass spectrometry determination: respectively adding internal standard ISTD elements with the same concentration into the standard solution, the test solution and the blank solution, and performing determination; and preparing a standard curve by using the standard solution, and calculating the concentration of the aluminum element in the test solution by using the standard curve. Compared with the prior art, the analysis method provided by the invention not only has lower requirements on the sample dosage, but also has higher accuracy and lower detection limit.

The invention discloses a method for determining the total phosphorus content in ammonium polyphosphate, and relates to the technical field of chemical analysis and detection. The method comprises the following steps: weighing an ammonium polyphosphate sample, putting the ammonium polyphosphate sample into a microwave digestion tube, adding a nitric acid solution, covering and sealing, putting the microwave digestion tube into a microwave digestion instrument for digestion, transferring a digestion solution into a volumetric flask for constant volume, uniformly mixing and filtering, and taking a filtrate as a to-be-tested solution; preparing a phosphorus pentoxide standard series solution; placing the standard series solution and the to-be-tested solution in a sample disc of a continuous flow injection analysis automatic sampler in sequence, setting parameters, operating the equipment for detection, fitting a standard curve according to peak height, calculating the mass concentration of phosphorus pentoxide in the to-be-tested solution, and further calculating the total phosphorus content in the sample. According to the method, microwave closed digestion is utilized, the reaction speed and intensity are higher in the process, the medium-high ammonium polyphosphate digestion is more thorough, a continuous flow injection analyzer is used for automatic sample introduction and determination, manual operation errors are reduced to the maximum extent, the detection flux is high, the speed is high, and consumed time is less.

The invention relates to the technical field of positive electrode material foreign matter detection, and particularly discloses a technology for detecting the number and content of foreign matters in an explosion-proof positive electrode material of a lithium battery. The method comprises the following steps: sampling a plurality of ton bags, uniformly dispersing a to-be-tested sample by taking absolute ethyl alcohol as a dispersing agent, and putting the to-be-tested sample into an ultrasonic machine by adopting a screen for ultrasonic screening until no obvious material residue exists on the screen; washing residues on the sieve with ultrapure water, carrying out suction filtration, and observing and acquiring quantity information of foreign matter particles through a cleanliness instrument; and finally, performing microwave digestion on impurities on the filter membrane, and testing the content of impurity elements by virtue of an inductively coupled plasma emission spectrometer, so that the interference of main elements in the sample is effectively eliminated. The method can realize efficient separation and accurate analysis of foreign matters in the positive electrode material, is high in detection sensitivity and simple and convenient to operate, can be widely applied to the quality control link of the positive electrode material, and provides reliable detection support for improving the safety performance of the positive electrode material.

The invention relates to the technical field of metal detection, in particular to a method for detecting gallium, germanium and indium in high-temperature vitreous furnace slag, which comprises the following steps: drying and grinding the high-temperature vitreous furnace slag, mixing with an alkali solvent, melting at high temperature, cooling, adding water, and filtering to obtain a precipitate containing gallium, germanium and indium; soaking and dissolving the precipitate with dilute acid, and then carrying out microwave digestion; and after digestion is completed, adding a boric acid solution to neutralize residual hydrofluoric acid, and detecting by adopting inductively coupled plasma mass spectrometry after volume metering. According to the present invention, the alkali melting is combined with the microwave digestion, such that the complete dissolution of the sample is achieved, the matrix interference is reduced, and the detection sensitivity and the detection accuracy are improved. The method has the advantages of short pretreatment time, safe operation, wide application range and the like, and can effectively solve the problems of complex sample pretreatment, low detection sensitivity and serious matrix interference in the prior art.

This invention discloses a method for determining the content and simultaneously identifying the source of polyglutamic acid (PCA) in fertilizers based on microwave digestion-high-resolution liquid chromatography-mass spectrometry (LC-MS), belonging to the field of analytical detection technology. The method includes: microwave-assisted acid hydrolysis of fertilizer samples to obtain a hydrolysate; injecting the hydrolysate into a liquid chromatography-high-resolution mass spectrometry (LC-MS) instrument, performing a single injection analysis in data-independent acquisition (DIA) mode, and simultaneously acquiring a mass spectrometry dataset containing a full-scan fingerprint of the parent ion and fragment information of the daughter ion by alternating between low and high collision energies; extracting the precise mass number of PCA from the dataset for accurate quantification, and calculating the PCA content using the difference method; simultaneously retrieving the total ion chromatogram and inferring the source of PCA based on the response of other amino acids. This invention is the first to introduce microwave digestion pretreatment and high-resolution mass spectrometry DIA acquisition mode into the field of PCA detection in fertilizers, requiring only a single injection to simultaneously complete accurate quantification and source identification, effectively avoiding false positives caused by background of plant and animal protein hydrolysates, and significantly improving the efficiency and confidence of PCA detection in complex matrix fertilizers.

The invention relates to the technical field of agricultural science, and discloses a method for treating a sample before total measurement of forest soil nutrients by a microwave digestion instrument, which comprises the following steps: S1, weighing, screening and air-drying the forest soil sample, so that the sample has uniformity; s2, preparing a proper acid liquid mixture according to the characteristics of the soil sample; s3, putting the treated sample and an acid solution into a microwave digestion instrument, and performing digestion according to a set heating program; s4, the digested sample is filtered, concentrated and subjected to volume metering, and nutrient analysis is prepared; and S5, determining the nutrients of the digestion solution by using an inductively coupled plasma light emission spectrometer. By optimizing the combination of acid liquor proportion and microwave heating, nutrients in a soil sample can be released more comprehensively and more efficiently, and the microwave digestion technology can provide uniform heat in a short time, so that the acid liquor is rapidly heated and permeates into the sample, accurate release of all important elements is ensured, and the analysis accuracy is improved.

1. The name of the design product: microwave digestion instrument (high temperature and high pressure). 2. The use of the design product: an experimental equipment for sample digestion. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view.

The utility model discloses a microwave digestion acid-driving observation device which comprises a longitudinal observation tube with a sealing lens at the lower end, and an illuminating lamp is arranged at the lower end part of the longitudinal observation tube or below the longitudinal observation tube. The upper end of the longitudinal observation pipe is connected with a transverse observation pipe of which the trend is vertical to the trend of the longitudinal observation pipe; a first reflective mirror used for reflecting light in the longitudinal observation pipe to the outer end of the transverse observation pipe is fixedly installed at the joint of the longitudinal observation pipe and the transverse observation pipe. When the acid-driving operation is observed, the longitudinal observation tube is inserted into the digestion tank or the lower end of the longitudinal observation tube is positioned at the opening of the digestion tank, the illuminating lamp is turned on, and an operator can observe the state in the digestion tank in the side direction of the digestion tank by means of the reflection direction change of the light rays by the reflective mirror. Therefore, the operation is simplified, the risk of acid gas overflow is reduced, and the operation safety is improved.

The invention discloses a method for microwave digestion of an express packaging material and application, and the method comprises the following steps: S1, crushing and grinding the express packaging material until the particle size is less than 100 [mu] m; s2, adding a composite acid-chitinase mixed solution into the digestion tank, and preliminarily contacting with the sample to weaken the structure of the sample; the composite acid-chitinase mixed solution comprises a composite acid mixed solution and a chitinase aqueous solution; the composite acid mixed solution comprises nitric acid, trifluoroacetic acid, hydrogen peroxide and formic acid; s3, placing the digestion tank treated in the step S2 on a turntable of a microwave digestion instrument, and carrying out pulse type microwave digestion; the microwave time is 25 minutes to 35 minutes; according to the method, pulse type microwaves are matched with the composite acid to digest the express packaging material, the digestion solution with high digestion completeness is obtained, HP-beta-CD and DTPA are used as double ligands to synergistically extract heavy metals such as lead and cadmium, the selectivity is good, and the efficiency is high.

The invention discloses a method for detecting mercury content in cordyceps sinensis, which comprises the following steps: taking cordyceps sinensis powder, pre-treating by adopting a microwave digestion instrument, and then detecting by adopting an inductively coupled plasma mass spectrometer. The test conditions of the inductively coupled plasma mass spectrometer are as follows: the mass numbers of mercury are selected to be 201 Hg and 202 Hg, the mass numbers of chromium, iron, nickel and tungsten are selected to be 52 Cr, 56 Fe, 60 Ni and 186 W, internal standards are selected to be 45 Sc, 72 Ge, 115 In and 209 Bi, an interpolation mode is adopted, and instrument determination is selected to be a KED collision mode. The method can effectively avoid false positive of the mercury test in the cordyceps sinensis, can accurately and reliably evaluate the quality of the cordyceps sinensis to prevent misjudgment, can cope with the specific doping problem of the cordyceps sinensis, and can also be applied to optimization of crushing equipment and crushing time in the crushing process.

The invention relates to the technical field of chemical analysis and detection, in particular to a method for detecting iodide ions in nylon slices. The method for detecting the iodide ions in the nylon slices comprises the following steps: placing the nylon slices in a microwave digestion tank, adding a potassium sulfate aqueous solution with the mass concentration of 0.9-1%, placing the nylon slices in a microwave digestion instrument for digestion, cooling after digestion is finished, and recording the nylon slices as a sample A; and directly introducing the prepared test solution A into an inductively coupled plasma emission spectrometer for determination, and calculating through an iodide ion standard curve to obtain the actual iodide ion content in the sample. According to the method for detecting the iodide ions in the nylon slices, only one-time microwave digestion is needed, multiple times of transfer or complex reaction are not needed, the extraction efficiency is high, and operation is easy; meanwhile, potassium nitrate is replaced by potassium sulfate, so that the accuracy and repeatability of a measurement result are further improved.

The invention discloses a super microwave digestion and conversion rate determination method for organic arsenic in animal and plant samples, which comprises the following steps: adding a mixed solution of nitric acid and sulfuric acid into a sample, and performing digestion and cooling by adopting super microwaves to prepare a sample solution; the super microwave digestion conversion rate of the organic arsenic in the animal and plant samples is measured by using inductively coupled plasma mass spectrometry (ICP-MS) and hydride generation-atomic fluorescence spectrometry (HG-AFS). The method has the advantages of simple process, adoption of one-step digestion with super microwaves, no need of repeated acid addition, reduction of energy consumption and cost, short time of super microwave digestion, high conversion rate of super microwave digestion, facilitation of realization of rapid detection, and meeting of requirements of basic food detection.

The utility model relates to experimental apparatus technical field, concretely relates to a microwave digestion appearance of quick sample taking and placing, including host computer and hinged setting in the sealed cover of host computer top surface, the host computer includes heat -proof shell and the microwave generating device of fixed mounting in heat -proof shell inner wall, the heat -proof shell top surface has the opening, the heat -proof shell is installed with lifting digestion jar device.

The invention provides a method and a device for microwave digestion of a geological sample under normal pressure, the method for microwave digestion of the geological sample under normal pressure comprises the following steps: S1, taking a first preset amount of geological sample, grinding until the granularity is less than 200 meshes, putting into a digestion bottle, and adding hydrofluoric acid with a first preset volume and nitric acid with a second preset volume; s2, standing for a first preset time for pre-digestion; s3, performing microwave digestion on the pre-digested geological sample for a second preset time until the geological sample is completely dissolved in a solution of hydrofluoric acid and nitric acid; s4, cooling the geological sample solution subjected to microwave digestion; s5, placing the cooled solution of the geological sample on a heating plate for heating, and performing acid removal on the solution of the geological sample at a first preset temperature until thick liquid drops appear at the bottom of the digestion bottle; s6, cooling to normal temperature, adding aqua regia, and fixing the volume to 100 ml; and S7, placing the sample in an inductively coupled plasma mass spectrometer to test trace elements in the geological sample.

The invention relates to the technical field of edible mushroom processing, in particular to low-molecular-weight hericium erinaceus beta-glucan with antioxidant activity as well as a preparation method and application of the low-molecular-weight hericium erinaceus beta-glucan. According to the method, the macromolecular hericium erinaceus beta-glucan is used as a raw material, the low-molecular-weight beta-glucan is prepared through microwave digestion and compound enzyme step-by-step degradation, the weight-average molecular weight of the prepared low-molecular-weight beta-glucan is 7.611 kDa, and compared with a high-molecular-weight beta-glucan sample, the low-molecular-weight beta-glucan is better in water solubility and lower in solution viscosity; the compound has the capability of efficiently scavenging free radicals, has good antioxidant activity, and has a wide application prospect.

The application discloses a microwave digestion tank with a rapid pressure reduction structure and relates to the technical field of microwave digestion tanks. The microwave digestion tank with the rapid pressure reduction structure comprises a tank body and a tank cover, an installation cavity is formed in the tank cover, a through hole is formed in the bottom of the installation cavity, and an exhaust pipe is fixedly connected to the top of the through hole. When the microwave digestion tank with the rapid pressure reduction structure is rapidly depressurized, high-pressure gas in the sealed cavity can be separated from liquid through a gas-liquid separation device when the high-pressure gas is discharged through the through hole, the gas is discharged, the liquid returns to the sealed cavity, the liquid in the tank body is prevented from being carried out by the airflow, and the accuracy of detection results is ensured.

The application relates to a microwave digestion instrument for pesticide sample pretreatment and relates to the technical field of pesticide residue detection. The microwave digestion instrument comprises a shell, the bottom of the shell is fixedly connected with a device seat, the top of the shell is provided with a controller, the outside of the shell is provided with a protection mechanism, the inside of the shell is provided with a heating mechanism, the outside of the device seat is provided with a dissipation mechanism, the protection mechanism comprises a rotating seat, the outside of the rotating seat is fixedly connected to the right side of the outside of the shell, the outside of the rotating seat is rotationally connected with an inner door, the outside of the inner door is fixedly connected with a pressing part, the left side of the outside of the shell is fixedly connected with an opening and closing seat, and the outside of the opening and closing seat is rotationally connected with an outer door. The application has the advantages that the inner door is driven to rotate through the rotating seat, the outer door is driven to rotate through the opening and closing seat, one side of the pressing part is supported on the outside of the shell, and the other side of the pressing part is supported on the outer door, so that the inner door and the outer door are tightly combined with the shell, and the sealing effect is improved.