31results about How to "Reduce preprocessing steps" patented technology

The invention relates to the technical field of detection of synthetic pigments and especially relates to a method of simultaneously detecting various synthetic pigments in wheaten foods via HPLC-DAD.The method includes the following steps: A) preparation of standard work solutions and samples; b) extraction of a sample solution; C) HPLC-DAD analysis to the solution prepared in the step B); D) calculation of content of to-be-detected substances with standard curve. In the HPLC-DAD detection method, pretreatment steps are simplified, wherein solid-phase extraction and concentration steps are avoided, thus reducing pretreatment time. Detection is carried under wavelength of 400-600 nm, so that interference due to majority of food additives and natural pigments is avoided. The method is accurate, quick and simple, has reliable quantitative results, can effectively detect ten artificially synthetic pigments in one time, and is very suitable for simultaneously treating samples in multi-batches.

The invention relates to a method for fast enzymolysis of hybrid proteins comprising: providing protein samples to be enzymolysis; obtaining the denatured protein samples after the degeneration treatment of said protein samples; treating said denatured protein samples by means of protease enzymolysis and assistant with ultrasonic, obtaining the protein polypeptide fragments. The invention also provides a method for fast identifying the protein. The method of the invention can quickly and high efficiently implement the protein enzymolysis and identification with easy operation and high accuracy.

The invention discloses a preparation method of a titanium oxide extraction bar for solid phase microextraction; in the method, a plurality of titanium oxide layers are deposited on the surface of polypropylene hollow fiber by adopting a sol-gel method, and then polypropylene matrix is removed by high-temperature firing, so as to obtain the titanium oxide hollow fiber extraction bar, realize extraction preenrichment to polar compounds with micro and trace amount in medicine and environment samples and carry out separation analysis to gas chromatography or high performance liquid chromatography; the extraction bar has a three-dimensional porous stricture, has larger specific surface area, controllable coating thickness, good chemical and heat stability, wide pH stabilization range (pH=1-14) and high extraction efficiency to the polar compounds.

The invention discloses a one-bath quick-bleaching agent for printing and dyeing and a preparation method and application of the one-bath quick-bleaching agent. The quick-bleaching agent comprises a component I, a component II and a component III, wherein the mass ratio of the component I to the component II to the component III is 1: 1: 2; The component I comprises a fiber amorphous region channel expanding agent accounting for 88% of the total mass of the component I, and the balance of water; the fiber amorphous region channel expanding agent comprises the following components in percentageby mass: 30-40% of benzyl benzoate, 10-15% of diethylene glycol phthalate or dipropylene glycol phthalate, 20-25% of dibutyl maleate, 15-25% of fatty alcohol-polyoxyethylene ether and 5-10% of ethylene glycol butyl ether; the component II comprises a dispersing agent accounting for 9-12% of the total mass of the component II and the balance of water; and the component III comprises a dye antioxidant accounting for 25-30% of the total mass of the component III and the balance of water. The preparation method is simple and feasible; a large amount of water can be reduced by adopting the quick-bleaching agent for printing and dyeing, the cost is reduced, and energy conservation and environmental protection are achieved.

The invention discloses a method for pretreating oil sludge waste in hazardous waste incineration disposal. The method comprises the steps that oil sludge model waste, lime and water are taken, the lime is ground through crushing equipment, the oil sludge model waste and the ground lime are mixed, water is added for stirring in the mixing process, and a mixed body is prepared; the mixed body is placed in a reaction still to be boiled, and elemental sulfur in the oil sludge model waste is converted into polysulfide; and the boiled material in the reaction still is taken out, pretreatment is completed, in the pretreatment process, the lime, the water and the oil sludge model waste react together to generate the polysulfide, then the situation that in the later treatment process, sulfide is heated to generate sulfur dioxide gas is effectively avoided, and meanwhile in order to enable the elemental sulfur in the oil sludge model waste to be completely converted, the amount ratio of the lime, the water and the oil sludge model waste is controlled. According to the method, the process is added in the waste pretreatment process, and sulfur dioxide gas can be prevented from being generatedlater.

The invention belongs to the field of analysis and detection, and particularly relates to a method for determining total nitrogen content based on an ion chromatography technology. The technical problem to be solved by the invention is to provide a method for determining the total nitrogen content based on an ion chromatography technology, which comprises the following steps: A, oxidizing and digesting a system to be detected by using alkaline potassium persulfate to obtain a sample to be detected, directly detecting the sample to be detected by using ion chromatography without adding acid forneutralization to obtain a peak area corresponding to nitrate radicals in the sample to be detected; wherein the leacheate of the ion chromatography is a system containing hydroxide radicals; B, replacing the system to be detected with isopyknic water, and obtaining the peak area corresponding to nitrate radicals in the blank group, wherein the rest contents are the same as those in the step A; and C, calculating to obtain the total nitrogen content of the system to be detected according to the standard curve and the data in the steps A and B. The method is suitable for detection of various nitrogen-containing substances, and has the advantages of few pretreatment steps, simple operation, good precision, good recovery rate, high accuracy and the like.

The invention discloses a method for detecting nitrofuran metabolite residues in chicken ossein and chicken bone white soup. The method comprises steps of (1) weighing a sample; (2) adding diatomite for grinding treatment; (3) adding extracting solution into the treated sample, and uniformly mixing; (4) carrying out derivatization treatment; (5) adjusting a pH value to about 7.2-7.5 by using acidand alkali; (6) extracting with ethyl acetate, and collecting extraction solution; and (7) carrying out 40 DEG C nitrogen blow-drying of the extract, and allowing 0.1% formic acid water to pass through a film machine at a constant volume for detection. The detection method of nitrofuran metabolite is simple, and pretreatment is convenient and efficient.

The invention provides a double digital PCR fluorescent quantitative detection method for transgenic maize 3272. According to the method, quantitative detection can be directly performed on the transgenic maize 3272 in genomes of samples to be detected, and therefore the standardard curve plotting step in quantitative detection of a conventional PCR method and the sample preprocessing step in existing digital PCR detection are omitted; in addition, transgenic ingredients are calculated according to the proportion of the exogenous gene copy number and the reference gene copy number, and therefore the stability of quantitative detection of the transgenic ingredients can be improved by performing double detection on one reaction system. Through the method, absolute quantitative detection on the transgenic maize 3272 can be achieved, the quantitative detection limitation can reach 0.5%, the sensitivity can reach 0.1%, and the requirements of actual detection of all the transgenic ingredients can be met. In addition, the method is easy to operate and high in flexibility and serves as an effective method for absolute quantitative detection of transgenes.

The invention discloses a method for detecting the concentration of cycloserine in bone tuberculosis specimens. The method includes the following steps: (1) the bone tuberculosis specimens are frozenby liquid nitrogen, after the liquid nitrogen is volatilized, a solvent is added for grinding and cycloserine extraction is conducted, and a tissue extraction solution is collected; (2) the tissue extraction solution and a cycloserine standard solution are detected through high performance liquid chromatography-mass spectrometry combination, and during measuring, if the retention time of a chromatographic peak of the tissue extraction solution is consistent with the retention time of a chromatographic peak of the cycloserine standard solution, selected qualitative ions all occur in a sample mass spectrum after background subtraction, and the abundance is consistent compared with the ion abundance of the cycloserine standard solution, and it is judged that the cycloserine is detected; and (3), according to data, obtained in the step (2), of the tissue extraction solution measured through high performance liquid chromatography-mass spectrometry combination, the content of the cycloserinein the bone tuberculosis specimens is quantitatively analyzed through an internal standard method, and thus the concentration of the cycloserine in the bone tuberculosis specimens is obtained. According to the method, the time of processing the bone specimens is shortened, and the measurement concentration is accurate.

The invention provides a box-packed fruit and vegetable low-temperature plasma airflow type cold sterilization device which comprises a box body used for containing fruits and vegetables; a plasma airflow generator which is positioned right above the box body and is used for generating low-temperature plasma airflow; a fan which is positioned right above the plasma airflow generator and is used for blowing the low-temperature plasma airflow into the box body; a flow guide body which is installed at the bottom of the plasma airflow generator and used for guiding plasma airflow to the surfaces of fruits and vegetables. The flow guide body is enclosed into a closed structural body, the bottom of the flow guide body is open and gradually contracts towards the inner side, and the bottom of the flow guide body extends into the box body; and an air outlet gap is reserved between the outer wall of the flow guide body and the box body, so that low-temperature plasma airflow flows back upwards from the bottom of the box body and flows out from the air outlet gap. The device can significantly increase the sample size and reduce the pretreatment steps, and can be used for external sterilization of the cold-chain logistics packaging box, so that the device can meet the requirements of large-scale production of fruits and vegetables in a cold-chain link.

An embodiment of the invention discloses a multi-medicinal fast thin-layer identification method and a containing device for reference materials of rehmannia and lycium root-bark decoc, and the identification method comprises the following steps of preparation of a control medicinal solution, preparation of two test solutions, and chromatographic detection and comparison of the test solutions andcorresponding control medicinal solution. The containing device comprises a cooling tank, a containing tank provided inside the cooling tank and used for containing the reference materials of rehmannia and lycium root-bark decoc, and a stirring structure rotatably provided inside the containing tank. In the invention, the adopted preparation method of two test solutions is simple and fast, and requires fewer pre-processing steps; at the same time, in the identification of five medicinal materials, the solvents in the test solutions and the reference medicinal solution only involve methanol orwater, so that the cost of the entire preparation method is effectively reduced, and the detection efficiency is greatly improved; compared with a conventional thin-film identification corresponding to a traditional medicinal material, the material is classified in the invention to further reduce the number of times of thin-layer identification, thereby realizing a new model of one test and multiple evaluations, and better improving the identification efficiency.

The invention relates to the technical field of analysis and detection, in particular to a detection method of acetylcysteine enantiomers. The detection method of the acetylcysteine enantiomer provided by the invention comprises the following steps: diluting a sample with a diluent, and carrying out HPLC (High Performance Liquid Chromatography) detection, the diluent is composed of ethanol and isopropanol; chromatographic conditions of the HPLC detection are as follows: a chromatographic column is a chiral column; a mobile phase is composed of normal hexane, isopropanol, ethanol and trifluoroacetic acid, and isocratic elution is carried out. When the method provided by the invention is used for detection, the pretreatment steps of the sample can be reduced. The detection result shows that the method provided by the invention can enable the L-acetylcysteine and the D-acetylcysteine to have better separation degree, and the accuracy, the sensitivity, the repeatability and the precision of the detection are all good.

The invention discloses an aluminum formwork wall corner slurry leakage prevention mechanism. The aluminum formwork wall corner slurry leakage prevention mechanism comprises an embedded assembly, a plugging assembly and a connecting assembly. The bottom wall of the embedded assembly is clamped to a steel bar, and the top wall of the embedded assembly is located below the top wall of a floor slab.The plugging assembly is provided with a leakage prevention section and a connecting flange, a plurality of aluminum formworks are arranged on the connecting flange, the side walls of the aluminum formworks abut against the outer wall of the leakage prevention section to form a pouring groove, the connecting flange is arranged on the peripheral wall of the leakage prevention section and extends towards the radial outer side of the pouring groove, and the bottom wall of the connecting flange is located below the top wall of the floor slab. The connecting assembly is arranged in the embedded assembly and the plugging assembly in a penetrating mode. According to the aluminum formwork wall corner slurry leakage prevention mechanism, the aluminum formwork wall corner slurry leakage phenomenon can be reduced, the construction efficiency is improved, and the construction cost is reduced.

The invention provides a pretreatment activation solution and a pretreatment method for aluminum and aluminum alloy electroplate. The pretreatment activation solution includes the following components: 20-30 g/L of fumaric acid, 3-5 ml/L of hydrofluoric acid, and water as a solvent. The pretreatment method includes the following steps: aluminum and aluminum alloy workpieces are subjected to oil removal and washed with water, then are subjected to alkali corrosion and washed with water, then are subjected to acid pickling and washed with water, are finally activated by the pretreatment activation solution, and then are washed with water after the activation. The pretreatment activation solution contains a composite antioxidant, can improve the bonding strength of aluminum and aluminum alloysurface coatings, and can be directly electroplated after the activation.