194results about How to "Obvious phenomenon" patented technology

The invention provides a failure point positioning method for semiconductor power device failure analysis. The failure point positioning method comprises the following steps of: performing chemical corrosion on a metal aluminum layer covering the surface of a power device by utilizing a chemical corrosion stripping technology, completely removing the aluminum layer, and completely keeping a barrier layer below the metal aluminum layer; positioning the front side of the power device by utilizing a micro light microscope and a light beam induced resistance variation technology, simulating electric conditions under the failure conditions, electrifying by using a point needle method, simulating the electric conditions, and finding possible failure points; and performing physical verification of electronic package assembly failure analysis by utilizing the positioning result of an electronic package assembly failure analysis tool on the previous steps, and finding the final physical failure point. The failure point positioning method has the advantages that the metal aluminum layer is effectively stripped, and the integrity of the barrier layer is kept; and moreover, the positioning speed and efficiency of the semiconductor power device failure point are greatly improved, and an extremely high precision is kept.

The invention relates to an inorganic/organic hybrid photochromic material, a preparation method and an application, which belongs to the inorganic/organic hybrid photochromic material field, and relates to a synthetic method and an application of a benzyl viologen bismuth chloride inorganic/organic hybrid photochromic compound. The benzyl viologen bismuth chloride inorganic/organic hybrid photochromic compound has excellent photochromism performance, is fast to change color under the irradiation of UV and visible light, and also fast to fade while being heated and placed in a darkroom, the material can be used in the fields of light information storage, protection decoration, fake resistance and authentic identification, secrecy, optical switch device, light information converter, photochromic sunglass lens used for radiation protection, diaphragm material and the like.

The invention discloses a novel ratio type sulfite fluorescent probe as well as a preparation method and biological application thereof. The structural formula of the probe is shown as a formula in the description. The probe has very high fluorescent light; after the probe is added into water or an organic solvent, an obtained solution is blue; after the probe acts with sulfite, the color of the solution is gradually faded and the color of the solution becomes green fluorescent. A synthesis process of the probe is simple and the yield of a prepared product is high. The novel ratio type sulfite fluorescent probe can be applied to a water body system, an organic solvent system or a biological system, and the sulfite is detected in a manner of enhancing and weakening fluorescent light of two wave bands and obviously changing the color; the novel ratio type sulfite fluorescent probe is high in selectivity and high in sensitivity.

The invention discloses a fluorescent probe for detecting hydrogen sulfide and a preparation method and application thereof. The fluorescent probe has a molecular formula of C21H21N4O+ and has a structure shown in the description. The fluorescent probe self has very weak fluorescence; when the fluorescent probe is added into water or an organic solvent, an obtained solution is purple; when the fluorescent probe reacts with hydrogen sulfide, the color of the solution gradually fades away, and fluorescence enhancement is shown. The fluorescent probe for detecting the hydrogen sulfide disclosed by the invention has high selectivity in hydrogen sulfide detection, high detection flexibility, an obvious phenomenon and convenience in recognition. The fluorescent probe for detecting the hydrogen sulfide disclosed by the invention is simple in preparation method, high in prepared product yield and suitable for large-scale popularization and application.

The invention relates to a test method, in particular to a rapid qualitative test method of chlorine dioxide in milk, and also relates to a rapid qualitative detection reagent kit of chlorine dioxide. The invention belongs to the technical field of the chemical composition detection. A qualitative adulteration test method of the chlorine dioxide performs the detection according the following procedures that: a test paper strip is immerged into a milk sample, whether the chlorine dioxide is remained or not in the milk sample is judged according to the color change of a test paper strip after being taken out, and the detection limit of the method is 0.0002 percent.

The present invention discloses preparation of carbon quantum dots having catalysis performance, and applications of a kit based on the carbon quantum dots. The carbon quantum dot preparation mainly comprises: carrying out oil bath heating on polyethyleneimine, cysteine, ethylene glycol, distilled water and solid phosphoric acid to obtain a pale yellow gel, dissolving with water, and naturally cooling to a room temperature; and treating the obtained brown gel product to obtain the product. The applications of the kit based on the carbon quantum dots mainly comprise: the characteristic that the carbon quantum dots catalyze and decompose hydrogen peroxide to organically combine two nanometer materials such as the carbon quantum dots and the gold nanoparticles, and the carbon quantum dots have biological enzyme property and the antibody and the antigen are specifically bound to form a sandwich structure so as to achieve the detection of breast cancer antigen and the hypersensitivity visual detection of ice drug. According to the present invention, the phenomenon is obvious, the operation is easy, the sensitivity is ultra-high, and the breast cancer antigen concentration in the serum and the ice drug content in human serum, saliva and urine can be effectively and accurately determined.

The invention relates to a method for controlling Pichia pastoris to ferment to produce an antibacterial peptide by utilizing dissolved oxygen parameters, and belongs to the technical field of biological engineering. The method comprises the following steps of: (1) calibrating the percent of dissolved oxygen (DO) to obtain a fermentation medium; (2) simultaneously marking the percent as a 0 pointand starting to ferment; (3) when the value of the DO is up to above 50 percent from 10 percent below, starting to feed methanol until the value of the DO falls back to 10 to 30 percent; stopping feeding the methanol; when the value of the DO is stably up to over 50 percent again, starting to feed the methanol again until the value of the DO falls back to 10 to 30 percent; stopping feeding the methanol; operating circularly; and controlling the value of the DO to be maintained between 10 and 30 percent all the time by feeding the methanol, adjusting ventilation and controlling a rotation speed; and (4) when the value of the DO does not fall back after feeding the methanol, finishing fermenting. The method of the invention has a short fermentation period and less dosage of the methanol; and compared with conventional dissolved oxygen value regulation and control, the method is easier to operate, and conditions are easier to grasp.

The invention discloses a preparation method and an application of a rapid detection kit for a copper-containing nanorod compound. The method comprises the following steps of preparing the copper-containing nanorod compound; adding glucose solutions with different concentrations into a centrifuge tube, adding glucose oxidase, adding the copper-containing nanorod compound and a color developing agent, adjusting the pH value, obtaining a standard curve with a good linear relation according to a relation between an absorbance value of the color developing agent at the wavelength of 652nm and theglucose concentration, and based on this, performing calculation to obtain the glucose content in a to-be-detected sample; and adding the copper-containing nanorod compound connected with an INS-aptamer into the centrifuge tube, adding insulin with different concentrations, adding a hydrogen peroxide solution and the color developing agent (TMB), obtaining a standard curve with a good linear relation according to a relation between the absorbance value of the color developing agent at the wavelength of 652nm and the insulin concentration, and based on this, performing calculation to obtain theinsulin content in the to-be-detected sample. The kit also can be used for distinguishing type 1 diabetes and type 2 diabetes. The method is obvious in phenomenon, easy and convenient in operation, high in sensitivity, and accurate and effective.

The invention discloses a quick detecting method for formaldehyde content in an aquatic product. The quick detecting method comprises the following steps: (1) preparing a Schiff reagent; (2) making a standard color chart, namely respectively adding 5mL formaldehyde solutions with different concentrations to 8 different colorimetric tubes, respectively adding a 0.5mL Schiff reagent to the colorimetric tubes, adjusting the pH of the solutions to 2.5, shaking up the solutions, stewing and developing for 10 minutes, and making the color chart by taking colors displayed by the solutions as standard colors; and (3) detecting, namely extracting a 5mL soak solution of an aquatic product sample to be detected, adding a 0.5mL Schiff reagent to the soak solution, adjusting the pH of the solution to 2.5, shaking up the solution, stewing and developing for 10 minutes, and comparing the color displayed by the solution with standard colorimetric splines. The quick detecting method disclosed by the invention has the characteristic that the formaldehyde and the Schiff reagent react at a normal state to generate a purple-red compound, and the shade of the compound is in direct proportion to formaldehyde content so as to realize colorimetric assay. The quick detecting method has the advantages of simple and quick operation, high sensitivity, simple conditions, low reagent price, and the like.

The utility model relates to a test method, in particular to a test method for adulteration of sodium sulfocyanate in raw milk, belonging to the technical filed of chemical composition test. In the test method for adulteration of sodium sulfocyanate in raw milk, the test is conducted according to the following steps: adding in the ferric salt solution of certain concentration in raw milk sample and judging whether the adulteration of sodium sulfocyanate exists in the raw milk sample according to the color change of the contact surface of ferric salt and raw milk sample. The test limit of the method is 0.01%.

The invention relates to a device for measuring light wave-particle duality and realizes verification and observation for wave-particle duality. The invention provides an observation device of the wave-particle duality which has the advantages of simple structure, easy construction, strong noise immunity, and easily observing measuring result. Single photon source, a light ring-shaped device and an X-shaped optical splitter/combiner are connected in turn to form the device. Moreover, the device is arranged two single photon detecting counter. The physical basis of the device is: when measuring corpuscular property, the device makes use of a characteristic of route random selection when the photons pass the X-shaped optical splitter/combiner, and a characteristic of prominently displaying classical particle motional orbits and locus; when measuring the wave character, the device makes use of Sagnac interferometer, a superposition characteristic when the photons meet at the X-shaped optical splitter/combiner, and an interference characteristic of prominently displaying classical wave.

The invention relates to an interferometric optical fiber humidity sensor based on graphene. The interferometric optical fiber humidity sensor comprises a glass slide pasted with a metal cylinder, andtwo single-mode optical fibers; the two single-mode optical fibers pass through the two sides of the metal cylinder correspondingly and are bent oppositely to form two crossed coupling points; and the two ends of the single-mode optical fibers are fixed to the glass slide, tapering is conducted on the middles of the single-mode optical fibers, tapered lumbar areas are located between the two crossed coupling points, the tapered lumbar area of one of the single-mode optical fibers is covered with a reduced graphene oxide film layer, and the two ends of the single-mode optical fiber covered with reduced graphene oxide serve as the input end and the output end correspondingly. The interferometric optical fiber humidity sensor is simple and compact in structure and easy to prepare, mutual fusion welding of optical fibers of special types is not needed, and thus the cost is low; and an optical fiber interference structure is suitable for sensing of gas of other types and biological and chemical sensing as well.