57results about How to "Meet the sensitivity requirements" patented technology

The invention discloses a mercapto-beta-cyclodextrin modified silver nano-rod array, its preparation method and its use. The array is a silver nano-rod array with the surface modified by mercapto-beta-cyclodextrin, wherein the lengths of silver nano-rods are 150-600nm, the diameters of the silver nano-rods are 60-90nm, the space between each two silver nano-rods is 10-40nm, and the substrate of the array is formed by superposing one or more than two of a silver film, a gold film, a copper film and a nickel film which have the thicknesses of 20-50mum. The preparation method comprises the following steps: obtaining a through hole alumina template through using a secondary anode oxidation method, sputtering a metal conductive film on one surface of the through hole alumina template through using an ion sputtering method to obtain an alumina template with the metal conductive film, carrying out electric deposition through placing the alumina template with the metal conductive film in a silver electrolyte to obtain an alumina template with holes provided with the silver nano-rods and one surface coated with the metal conductive film, etching off the alumina template through putting the resultant alumina template in an acidic or strongly alkaline solution, and immersing the resultant material in an aqueous solution of the mercapto-beta-cyclodextrin for at least 1h to prepare the mercapto-beta-cyclodextrin modified silver nano-rod array. The mercapto-beta-cyclodextrin modified silver nano-rod array can be used for rapidly detecting trace PCB77 or PCB101.

The invention discloses a preparation method of an alpha-Fe2O3/TiO2 nano-composite gas sensing material. The preparation method comprises the following steps: dispersing FeCl3.6H2O into a mixed solution of deionized water and ammonia water; stirring for 10 to 20 minutes; transferring the obtained mixed solution into a hydrothermal reactor; adding a prepared TiO2 nanofiber material; heating the hydrothermal reactor to be 95 DEG C for reacting for 4 hours; cooling the hydrothermal reactor to a room temperature; centrifuging sediment in the reactor with an ethanol solution repeatedly; drying at the temperature of 55 to 65 DEG C for 24 hours; calcining the material at the temperature of 500 DEG C for 2 hours to obtain the alpha-Fe2O3/TiO2 nano-composite gas sensing material. In the preparation method, the alpha-Fe2O3/TiO2 nano-composite gas sensing material prepared by combination of an electrostatic spinning technology and a hydrothermal method has a one-dimensional dentritic heterostructure, and can show a high gas sensing characteristic.

The invention discloses infrared phase locking and imaging method and device for surface and subsurface defect detection of an optimal element. The method and the device provided by the invention combine an infrared imaging technology with a phase locking amplification and detection technology; high-resolution image information related to the defect of a sample can be obtained by using a modulated pump laser excitation sample to generate periodic infrared radiation, using an infrared detection array to detect the generated infrared radiation, and carrying out phase locking amplification and detection on signals of the infrared detection array; and meanwhile, the influence of infrared signals inside a sample body on a detection result is eliminated by using the physical property that the penetration depth of the excited infrared radiation on some optical materials within a selected waveband is very limited, so that the imaging detection is only carried out on absorption defect distribution of the surface and subsurface of the sample. The method and the device are applicable to the detection and the imaging of the surface and subsurface absorption defect of the optical element, and are particularly suitable for the detection and the imaging of the surface and subsurface absorption defect of the common large-caliber optical element in an outsize high-power laser system.

The invention discloses a method and a device for measuring the accurate contents of core components of a liquid beverage in situ in the production process. The measurement can effectively provide timely information, can improve the product quality control level greatly, and can reduce the production cost. The technique also can be used for performing brand identity and supervision at the stages of transportation, storage and consumption of a liquid beverage; the mouthfeel and the value of the liquid beverage are normally determined by the contents of a small amount of core components of the liquid beverage, for example, the core components of beer are ethyl alcohol and carbon dioxide at the dissolved state; the core component of white wine and fruit wine is ethyl alcohol at the dissolved state; the core component of carbonated beverages is carbon dioxide at the dissolved state. The invention discloses a sensor based on a mid-infrared ray internal total reflection principle, which can be used for measuring the core components continuously and accurately on a production line synchronously; a characteristic absorption peak between 2.70 micron and 3.40 micron of ethyl alcohol at the dissolved state is selected, and the ratio of ethyl alcohol at the dissolved state is detected; a characteristic absorption peak at 4.27 micron of carbon dioxide at the dissolved state is selected. The measurement accuracy rate is higher than 99%, and the possible interference of a large number of solvent water molecules can be excluded effectively.

The invention discloses a temperature-sensing wax mixture for a temperature-sensing component, comprising paraffin wax and heat-conducting carbon fibres having a heat conductivity coefficient of greater than 450 w/m.k. A preparation method for the temperature-sensing wax mixture comprises the following steps of: proportioning the paraffin wax and the heat-conducting carbon fibres in a certain proportioning ratio by weight, uniformly mixing, and then grinding for 50-120 hours by adopting a high-energy ball mill under the protection of an inert gas, thus coating a layer of paraffin wax protecting film around the heat-conducting carbon fibres, and then obtaining the temperature-sensing wax mixture. According to the temperature-sensing wax mixture, the heat-conducting carbon fibres are used for replacing copper powder, so that the cost is low, and the thermal expansion is good, and the selected heat-conducting carbon fibres have a heat conductivity coefficient of greater than 450 w/m.k, so that a response speed for temperature sense is greatly increased, and adaptability to application occasions with a high sensitivity requirement on the temperature-sensing component can be met; simultaneously, the heat-conducting carbon fibres and the paraffin wax are mixed and then ground by adopting the high-energy ball mill, thus coating a layer of paraffin wax protecting film around the heat-conducting carbon fibres, so that the heat sensitivity of the whole temperature-sensing wax mixture can be improved, and the process is simple and beneficial to industrialized production.

The invention relates to a method for detecting related substance in tauroursodeoxycholic acid, and especially relates to a method using a HPLC-ELSD technology to simultaneously detect eight related substances in tauroursodeoxycholic acid. According to the method, an octyl bonded silica gel chromatographic column and an evaporative light-scattering detector are adopted; and a mobile phase (A) and a mobile phase (B) are mixed to carry out isocratic elution or gradient elution, wherein the mobile phase (A) is an ammonium salt buffer solution with a concentration of 2.5 to 50 mmol/L, and the mobile phase (B) is methanol or acetonitrile. The provided method has the advantages of simpleness, rapidness, accuracy, reliability, and good resolution of chromatographic peaks, and is capable of simultaneously detecting eight related substances in tauroursodeoxycholic acid quantitatively or qualitatively.

The invention discloses a composite sensing membrane composed of polypyrrole, fluorescein isothiocyanate and porous alumina as well as a preparation method and an application of the composite sensing membrane. The composite sensing membrane is formed by orderly coating inner walls of the hole of a porous alumina membrane with polypyrrole and fluorescein isothiocyanate, wherein the porous alumina membrane is 70-90 mu m, the hole density is 109-1011/cm<2>, the holes are through holes, and the diameter of each hole is 26-35nm. The preparation method comprises the following steps of: orderly dropping pyrrole ethanol solution and ferric chloride solution to the porous alumina membrane; putting the porous alumina membrane with the pyrrole ethanol solution and the ferric chloride solution under the negative pressure equal to or less than 0.1MPa for at least 10min; carrying out the ultrasonic cleaning to the porous alumina membrane with deionized water and ethanol so as to obtain the porous alumina membrane coated with polypyrrole on the surface and the inner wall of the holes; then immersing the porous alumina membrane into the fluorescein isothiocyanate ethanol solution with the concentration of 10<-3> to 10<-5>M for at least one hour; and washing the fluorescein isothiocyanate on the surface of the porous alumina membrane with ethanol to obtain the target product (composite sensing membrane). According to the composite sensing membrane, the trace 2,3,3'-trichlorodiphenyl can be effectively detected.

The invention relates to a rapid switching mode variable impedance transformer adaptive current protection method, characterized by comprising the following steps: 1) measuring the real-time three-phase voltages Ua, Ub, and Uc as well as the three-phase currents Ia, Ib and Ic at the wire inlet end of the transformer; then, using the symmetrical component method to convert the A-phase voltage and current, B-phase voltage and current and C-phase voltage and current into positive/negative zero-sequence voltages and currents; and 2) using the fault component method; based on the positive/negative zero-sequence voltages and currents in the normal state and the positive/negative zero-sequence voltages and currents in the fault state, calculating the fault components of the positive/negative zero-sequence voltages and currents. The protection method, through the real-time rectification of the current values, can meet the requirement for the sensitivity of a backup protection system so as to well address the problem that traditional protection is insufficient in sensitivity.

The invention provides an outlet housing for a range hood. The outlet housing comprises a lower housing connected with the range hood, an installation ring connected with an air outlet pipe, and valveblades capable of being turned over to be opened. The lower housing and the installation ring form an air outlet cavity of the outlet housing; an air inlet opening of the outlet housing is formed inthe bottom part of the lower housing; an air outlet opening of the outlet housing is formed in the top part of the installation ring; the valve blades are two valve blades rotating oppositely; the twovalve blades are connected into the air outlet cavity through a rotary shaft, and can be turned over to be opened or closed so as to connect or disconnect the air inlet opening and the air outlet opening; the two valve blades can form an opposite valve blade included angle ranging from 0 degree to 180 degrees; and the outlet housing outputs a corresponding detection capacitance value according tothe valve blade included angle. The two valve blades with different polarities can form a variable capacitance device, the outlet housing outputs the corresponding detection capacitance value according to the valve blade included angle, and the range hood can judge an open-close state of the valve blades according to the capacitance value detected in real time.

The invention discloses a biosensor for detecting tobramycin. The biosensor comprises an aptamer probe, a hairpin probe H1, a hairpin probe H2, Klenow Fragment polymerase, Nt.BbvCI endonuclease, a buffer solution and graphene oxide. The sequence of the aptamer probe is as shown in SEQ ID No: 1, the aptamer probe is formed by hybridizing an aptamer Aptamer with the sequence as shown in SEQ ID No: 2 and an amplification template T with the sequence as shown in SEQ ID No: 3. The sequence of the hairpin probe H1 is as shown in SEQ ID No: 4, and the sequence of the hairpin probe H2 is as shown in SEQ ID No: 5. When the biosensor is used for detecting tobramycin, the method is simple, the practicability is good, the stability is high, the detection lower limit reaches 0.06 nM and is lower than that of the existing similar sensors, and the biosensor has wide application prospects in the fields of environmental monitoring and food safety.

Photoelectrical mouse includes light emitting diode, set of lens for receiving beam reflected from plane of placing mouse, and optical inductor for receiving beam from the set of lens and determining position of mouse. Characters are that the disclosed mouse also includes key button for decreasing scanning precision, key button for increasing scanning precision, and calculator of scanning precision, and DSP in optical inductor. Based on initial value of mouse scanning precision, decreasing and increasing commands, final value of calculated scanning precision is output. Game player can adjust scanning precision of mouse without need of exiting from game so as to meet requirements of different sensitivities of mouse.

The invention discloses a device for continuously collecting shale desorption gas, which comprises a first gas collection device, a second gas collection device and a valve position switching device, wherein the first gas collection device and the second gas collection device are connected with the valve position switching device; the valve position switching device is connected with a water inlet device and a shale desorption device; the first gas collection device and the second gas collection device are alternately communicated with the water inlet device and the shale desorption device by valve position switching of the valve position switching device; the first gas collection device is communicated with the shale desorption device for water drainage and gas collection; the second gas collection device is communicated with the water inlet device for water inlet; and when the first gas collection device is full of shale gas collected in the first gas collection device, the valve position switching device performs the valve position switching, the second gas collection device is communicated with the shale desorption device for the water drainage and the gas collection, and the first gas collection device is communicated with the water inlet device for the water inlet. According to the device, a mode of reciprocating alternation of the two gas collection devices is designed based on a continuous measurement guide idea, and the continuity of a measurement process is ensured.

The invention discloses a digital micro-fluidic chip device for nucleic acid detection and a use method. A nucleic acid detection aqueous phase solution and an oil solution with the specific gravity smaller than that of water are added to a chip sample inlet at a time, then a chip is fixed on centrifugal equipment, and a water phase and an oil phase can be driven to enter the chip through centrifugation for 10-20 minutes. Finally, the result that the water phase is distributed in a micro-cavity of the chip and the oil phase is distributed in a micro-pipeline is obtained. Only 1-3 nanoliters of volume of reagent is needed for chip analysis of the invention. The analysis cost is greatly reduced, and the requirement on the sample content is reduced. The water phase and the oil phase can be injected into the chip at the same time, impurities are prevented from being introduced in multi-step experiments, and the accuracy of analysis is improved. The chip is simple in design principle, and samples can be separated by a one-step method only through a centrifugal device, so that digital PCR detection is realized.

The invention relates to an apremilast related substance determination method. According to the method, an octadecyl silane bonded silica gel filler chromatographic column is adopted; a buffer solution is used as a mobile phase A, the buffer solution is phosphoric acid, a phosphate solution or a mixture of the phosphoric acid and the phosphate solution, the concentration of the buffer solution is 0.001 mol/L to 0.1 mol/L, and the pH value of the buffer solution is 2.5 to 2.9; acetonitrile is used as a mobile phase B; the flow velocity is 0.8 ml/min to 1.2 ml/min, an ultraviolet detector is used for detection, and gradient elution is carried out. The apremilast related substance determination method is simple in mobile phase system, short in analysis time and high in sensitivity; since the absorption wavelength of known impurities and the detection number of unknown impurities are comprehensively considered, the detectability is better.