45results about How to "Improve the lower limit of detection" patented technology

The invention discloses a particulate matter mass concentration detection device applied to atmosphere suspended particulate matters, and a method thereof. The particulate matter mass concentration detection device is composed of a particulate matter sampling unit, a particulate matter measuring sensor, and a signal processing unit; the particulate matter sampling unit comprises air pumps, a particulate cutting head, a high-efficiency gas filter, a gas flowmeter, gas conduits, and a sampling power supply; the particulate matter measuring sensor comprises a multichannel particulate measuring part, a high-stability laser, an optically trap, a sheath gas unit, a metal capillary, optical lenses, and high-performance photoelectric detectors; and the signal processing unit comprises a signal conditioning circuit, a data acquisition card, a computer, and a signal power source. The particulate matter mass concentration detection device is reasonable in design; manufacturing and installation are convenient; and measuring optical path pollution caused by particulate matters is not caused. The signal processing unit is simple in structure, and excellent in performance; and data processing and reading are both convenient to realize. The measured particulate matter mass concentration dynamic performance is excellent; precision is high; and linearity is high.

The invention relates to a preparation method and application of a miniature high-efficiency clenbuterol immuno-affinity chromatography column. The technical scheme is characterized by comprising the following steps of: preparing a high-quality antibody, synthesizing efficient prepared bromoacetyl chloride clenbuterol purified by a liquid chromatogram and thiolation hemocyanin into immunogen immune animals, and obtaining antiserum; reacting the purified bromoacetyl chloride clenbuterol with thiolation agarose to obtain clenbuterol-agarose padding, loading the padding into an antigen affinity chromatography column; and purifying a clenbuterol specific antibody in the antiserum by using the antigen affinity chromatography column. The preparation method of the clenbuterol immuno affinity chromatography column comprises the following steps of: coupling high-quality antibodies at high density to the agarose oxidized by periodic acid to prepare an antibody affinity padding, and placing 25 mul of padding in a small specially-made column to prepare the miniature immuno-affinity chromatography column. The immuno-affinity chromatography column provided by the invention can be used for specifically gathering clenbuterol in a sample to be tested at high efficiency and can increase the accuracy, reliability and sensitiveness of detection when being combined with an analytic instrument and colloidal gold test paper for use.

The invention discloses a composite gas sensing material, which comprises multiple layers of reduced graphene oxide. Zero-dimensional cuprous oxide quantum dots are loaded on the surface of the reduced graphene oxide, and one-dimensional cuprous oxide nanowires and / or three-dimensional cuprous oxide nanoparticles fill the gap between adjacent two layers of reduced graphene oxide. The invention also discloses a preparation method. The method comprises steps of preparing a mixed solution of a copper acetate solution and a graphene oxide dispersion solution, dripping a sodium hydroxide solution to the mixed solution to obtain breen precipitation, adding the precipitation to a reductant solution for a heating reaction to obtain black precipitation, and cleaning and sealing the black precipitation to obtain a composite gas sensing material. The invention also discloses a gas sensor made of the composite gas sensing material and applications of the gas sensor. The technical problem that thegas sensing material in the prior art can respond to the gas only by means of auxiliary means can be solved, the sensitivity to nitrogen dioxide at room temperature can be improved, and a response canbe given to ammonia at the room temperature.

The invention relates to a photoelectric detecting system, in particular to a stray light jamming resistance photoelectric detecting system based on digital phase locking. The system comprises a light source, a TTL signal generator, an optical modulator, a sensor, a pre-amplifier and a lock-in amplifier, wherein the TTL signal generator or the optical modulator perform modulation on the light source, a modulated modulation light source and stray jamming light are converted into output measuring signals and jamming signals through the sensor, the measuring signals and the jamming signals are transmitted to the lock-in amplifier after being amplified by the pre-amplifier, and the lock-in amplifier is set to be only allowed to be passed by the measuring signals with the same frequency characteristics as the lock-in amplifier. According to the system, the measuring signal-to-noise ratio can be remarkably improved, the measuring lower limit can be effectively expanded on the condition that the light source power is not increased, and the system is particularly applicable to a pollutant monitor with the weak measuring signals, and is also applicable to stray light suppression of other optical measuring instruments.

The invention discloses an organic fluorescent sensation probe for detecting Fe<3+>. A preparation method of the organic fluorescent sensation probe comprises the following steps: mixing an oily fluorescent sensation material with formic acid, and performing backflowing for 1 hour at 40-90 DEG C so as to obtain raw material probe molecules with protected groups; mixing the raw material probe molecules with tri-halogen phenol, and performing backflowing for 24 hours at 55-110 DEG C with a catalyst, thereby obtaining the organic fluorescent sensation probe. The organic fluorescent sensation probe is good in water solubility, good in biocompatibility and wide in inspection range, the advantages that an organic fluorescent probe is good in material specificity and high in sensitivity are maintained, the lower detection limit of iron ions can be greatly increased, and the lower detection limit of the probe is at a world leading level.

The invention relates to a fluorescence type glucose capillary biosensor. The biosensor comprises nano sensors, a capillary coupling device, capillaries, a light source, a fiber optic spectrometer and a probe, wherein the nanometer sensors are distributed on the inner walls of the capillaries; the capillary coupler is connected with optical fibers and hoses; the optical fibers can be used for receiving an exciting light generated by the light source; the hoses can be used for receiving liquid to be detected; and a new fluorescence spectrum generated by the liquid to be detected and the nano sensors under the excitation of an evanescent field produced by the exciting light is received by the probe, and the probe transmits the received fluorescence spectrum to the fiber optic spectrometer to be analyzed. According to the fluorescence type glucose capillary biosensor, the capillaries are adopted for sampling, thus the dosage of samples to be detected can be obviously decreased, and reagents are saved. A fluorescence signal is excited through the evanescent field, therefore, the background fluorescence in a biological sample can be reduced efficiently, and the lower detection limit can be elevated.

The invention discloses a detection system of an oil-consuming device, belongs to the technical field of electrical detection equipment, and solves the technical problem of low efficiency of an oil paper aging detection mode in the prior art. The detection system comprises: a light source device capable of emitting at least two laser beams; a light source modulation assembly which can modulate a light source and / or change the energy level of the light source; a beam expanding and collimating device which is used for aggregating or combining different light sources; a detection assembly which can store air in an oil bin in the oil consuming device and can enable the light source aggregated by the beam expanding and collimating device to penetrate through the stored air, wherein the energy level and modulation of laser emitted by the light source device are changed through the light source modulation assembly, the laser is aggregated through the beam expanding and collimating device, andthe aggregated laser enters the detection assembly to complete the detection of the insulating oil paper. The detection system is used for perfecting the use function of an oil device, and meets therequirement of people for high insulation oil paper detection efficiency.

The invention relates to the detection field, and specifically relates to a method of utilizing a diagnostic marker to evaluate the early stage toxicity of trace exogenous chemicals and applications thereof. The diagnostic marker is one or more of L-valine, N-actyl-L-aspartic acid, lysolecithin, creatinine, and 2-phosphoglyceric acid. People find that exogenous chemicals can break the balance of amino acids in zebra fish and influence the decomposition and metabolism of proteins; the disturbance in the growth period is associated with the mechanism of toxicity; and the inventor finds that thesensitivity of a toxicity predicting method can be largely improved by combining a zebra fish model with metabonomics. Thus, the change of the zebra fish metabolite index can be used to judge the early stage toxicity of exogenous chemicals.

An electrochemical sensor for the dissolved HS can be used in the extreme environment has Ag / Ag2S electrode and reference metal / metal oxide electrode. Said Ag / Ag2S electrode has a metallic conducting wire, a teflon tube surrounding said metallic wire, the silver contained epoxy resin between them, and an Ag / Ag2S film covering its end. Said reference electrode has a metal wire with active oxide film on its surface. Its advantages are fast response, high sensitivity and long service life.

The embodiment of the invention discloses a detecting system for test paper. The system comprises a detecting unit used for information collection, and a colorimetric photosensitive device used for information processing and analysis, wherein the detecting unit is a black detecting card; the colorimetric photosensitive device comprises a light-emitting unit, an optical imaging unit and a photoelectric processing unit. The detecting system has more accurate analytical sensitivity, and through the adoption of the detecting system, the lower limit of the detection of products can be effectively improved, and the range of clinical detection can be enlarged.

The invention discloses a composite gas-sensing material, comprising multi-layer reduced graphene oxide, the surface of the reduced graphene oxide is loaded with zero-dimensional cuprous oxide quantum dots, and one-dimensional cuprous oxide is filled between two adjacent layers of reduced graphene oxide nanowires and\or three-dimensional cuprous oxide nanoparticles. Also disclosed is a preparation method, comprising preparing a mixed solution of copper acetate solution and graphene oxide dispersion, adding dropwise sodium hydroxide solution to the mixed solution to obtain a brown-green precipitate, adding the precipitate to a reducing agent solution for heating reaction , a black precipitate is obtained, and the black precipitate is cleaned and sealed to obtain a composite gas-sensing material. A gas sensor made of the composite gas sensitive material and the application of the gas sensor are also disclosed. The invention solves the technical problem that the gas-sensitive material in the prior art needs auxiliary means to respond to gas, can improve the sensitivity to nitrogen dioxide at normal temperature, and can also respond to ammonia gas at normal temperature.

The invention relates to the detection field, and specifically relates to a method of utilizing a diagnostic marker to evaluate the early stage toxicity of trace exogenous chemicals and applications thereof. The diagnostic marker is one or more of L-valine, N-actyl-L-aspartic acid, lysolecithin, creatinine, and 2-phosphoglyceric acid. People find that exogenous chemicals can break the balance of amino acids in zebra fish and influence the decomposition and metabolism of proteins; the disturbance in the growth period is associated with the mechanism of toxicity; and the inventor finds that thesensitivity of a toxicity predicting method can be largely improved by combining a zebra fish model with metabonomics. Thus, the change of the zebra fish metabolite index can be used to judge the early stage toxicity of exogenous chemicals.

The present invention relates to an immunomagnetic bead used for enrichment and purification of DON, and a preparation method and application thereof. The carboxyl magnetic bead is used as a carrier, a DON monoclonal antibody is used as a recognition intermediate, and after activation-coupling-washing- The blocking process prepares immunomagnetic beads coupled with DON monoclonal antibody, and incubation in a suitable buffer under certain conditions can efficiently capture and enrich DON in the detection sample. The immunomagnetic beads used for the enrichment and purification of DON has the advantages of concentrating the DON concentration in the sample to be tested, increasing the lower limit of detection, eliminating the interference of impurities, improving the detection accuracy and reliability, and reducing the sample processing time to achieve rapid detection.

The invention relates to a T-2 toxin-enriched immunomagnetic bead as well as a preparation method and application thereof. The T-2 toxin-enriched immunomagnetic bead is characterized in that a carboxyl magnetic bead is taken as a carrier and a T-2 toxin monoclonal antibody is used as an identifying intermediate, an immunomagnetic bead coupled with the T-2 toxin monoclonal antibody is prepared by the processes of activating, coupling, washing and closing; the immunomagnetic bead is incubated in a proper buffer solution under certain conditions for efficiently capturing and enriching the T-2 toxin in a detection sample. The T-2 toxin-enriched immunomagnetic bead disclosed by the invention has the advantages of concentrating the T-2 toxin in an to-be-detected sample, improving a lower detection limit, eliminating impurity interference, improving the accuracy and reliability of detection, shortening treatment time of the sample and achieving quick detection.