39results about How to "Low detection threshold" patented technology

The invention provides a laser radar, a laser radar system for reducing an ambient light interference and a detection method thereof. The laser radar system integrates all portions. The laser radar system for reducing the ambient light interference comprises an ambient light collection module and a management module. The ambient light collection module collects an electrical signal related to surrounding ambient light intensity of a target object. The management module comprises an analysis module and a control module. The analysis module is connected to the ambient light collection module andthe control module in a communication connection mode, wherein the analysis module of the management module analyzes the acquired electrical signal and generates a control signal which is related tothe control of the laser radar. The control module controls a laser emitting end and/or a laser receiving end of the laser radar according to the control signal.

An intrinsically safe, precise, and cost effective storage tank leak detection system. Embodiments include a highly precise quartz crystal type pressure transducer, secured in a vacuum and held at a constant temperature. Said transducer is used in combination with data correction and regression techniques to yield a storage tank leak detection system with an extremely low leak detection threshold. The storage tank leak detection system is thought to be most useful for detecting very small leaks in very large storage tanks.

A method for optically examining the interior of turbid media is provided. The method comprises the steps: providing broad-band light (2); spatially separating a plurality of wavelength bands (2a, 2b, . . . , 2n) contained in the broad-band light; separately modulating the plurality of wavelength bands (2a, 2b, . . . , 2n); recombining the plurality of modulated wavelength bands to a beam (11) of spectrally encoded broad-band light; illuminating a turbid medium (8) with the beam (11) of spectrally encoded broad-band light; detecting light emanating from the turbid medium (8) with a detector (9) and demodulating the detected light with a demodulator (10) to provide spectroscopic information.

An intrinsically safe, precise, and cost effective storage tank leak detection system. Embodiments include a highly precise quartz crystal type pressure transducer, secured in a vacuum and held at a constant temperature. Said transducer is used in combination with data correction and regression techniques to yield a storage tank leak detection system with an extremely low leak detection threshold. The storage tank leak detection system is thought to be most useful for detecting very small leaks in very large storage tanks, most likely above ground storage tanks.

The present invention aims to provide an odorant for fuel gases for anion membrane fuel cells, which does not generate a harmful sulfur compound after combustion and does not deteriorate the performance of a fuel cell, while enabling leakage detection at low concentrations, and which enables detection of leakage of a gas by a means other than odor, for example, by visual observation. The odorant for fuel gases for anion membrane fuel cells, imparts a fuel gas with an odor, and is characterized in that the odorant contains at least one or more substances selected from the group consisting of ammonia, trimethylamine, triethylamine, N,N-diethylmethylamine, N,N-dipropylmethylamine, N,N-dipropylethylamine, N,N-diisopropylmethylamine, N,N-diisopropylethylamine, dimethylamine, diethylamine, dipropylamine, ethylmethylamine, propylmethylamine, propylethylamine, methylamine, ethylamine and propylamine.

The present invention relates to electronic devices for the high sensitivity and selectivity detection and identification of volatile compounds in a gaseous medium, as well as of dissolved compounds in aqueous solutions. The claimed integrated circuit is intended for detecting and identifying analytes in a multicomponent medium and comprises at least one first microfluidic channel integrated in at least part of the integrated circuit surface, at least one ion-selective transistor with a sensitive surface and a circuit for processing the transistor signals. Furthermore, the first microfluidic channel has an inner surface and an outer surface. At least part of the first microfluidic channel outer surface is made in the form of a porous hydrophobic membrane. Moreover, the sensitive surface of the ion-selective transistor is located in the first microfluidic channel under the porous hydrophobic membrane, and at least one sensitive surface pad of the said transistor is functionalized with at least one type of biological receptor for binding the analyte of interest. The present invention also relates to a device for detecting and identifying analytes in a multicomponent environment, comprising a substrate, the above-described integrated circuit located on top of the said substrate and an encapsulating layer on top of the integrated circuit. That said, at least one medium supply channel and at least the second microfluidic channel are located in the encapsulating layer in such a way that the second microfluidic channel is connected to the first microfluidic channel and the medium supply channel is located in the porous hydrophobic membrane region. The technical result achieved by the proposed invention implementation is to reduce the lower detection threshold of a «bioelectronic nose» or «bioelectronic tongue» type device, to increase its selectivity in the target compounds identification, to increase the system response rate and to reduce the analysis time in general.

The invention discloses a small fault detection method of a sampling mechanical arm closed-loop control system. The method comprises the following steps: designing a self-adaptive neural network controller of a discrete time mechanical arm; constructing a dynamic estimator to approach the unknown dynamic state of the system; calculating a system dynamic residual error caused by the fault and a residual error compensated by a controller, and further obtaining an enhanced total measurable fault residual error; calculating an absolute fault residual accumulated value of weighted recursion; and designing a fault detection decision scheme, comparing a fault residual accumulation value obtained through real-time calculation with a self-adaptive threshold value, and if a certain moment exists and the fault residual accumulation value is larger than the self-adaptive threshold value, judging that the mechanical arm breaks down at the moment. According to the fault detection scheme, it is guaranteed that after the mechanical arm system breaks down, rapid fault detection is achieved, the problems that the faults change frequently and the fault diagnosis speed is low are solved through an absolute residual accumulation mechanism of weighted recursion, and the safety and rapidity of the fault detection system are guaranteed.

The invention discloses a method and kit for high throughput testing of enzymatic activity in lipase in a liquid milk product. The kit for testing of the enzymatic activity in the lipase in the liquid milk product comprises a reagent 1 and a reagent 2 which are independently packaged. The reagent 1 is a glycine-sodium hydroxide buffer solution, the pH value of the reagent 1 is 8.0-10.0, and the reagent 2 is an acetonitrile solution of p-nitrophenyl ester. The method is used for testing the enzymatic activity in the lipase in the liquid milk product through the kit, theoretical basis is provided for classification of raw milk, and fresh and raw milk quality control indexes suitable for producing and processing various kinds of liquid milk can be formulated, such as predicting UHT milk shelf life, scientifically guiding UHT product partition selling, lowering product metamorphism caused by residual lipase activity and protecting enterprise benefits and consumer benefits. The testing method is high in sensitivity, and the detection threshold value of lipase is low.

The invention discloses a lever-type bidirectional surface acoustic wave acceleration sensor. The lever-type bidirectional surface acoustic wave acceleration sensor comprises a metal shell, a movablebearing, a rigid lever, an inertia mass block, two pressure transmission rods and two surface acoustic wave sensor devices; the movable bearing is fixed in the center of the top surface of the metal shell; one end of the rigid lever is fixedly connected with the movable bearing, and the other end of the rigid lever is connected with the inertia mass block; the surface acoustic wave sensor devicesare both connected with the metal shell and are symmetric relative to the rigid lever; and one end of each pressure transmitting rod is vertically and fixedly connected with the rigid lever, and the other end of each pressure transmitting rod contacts with the corresponding surface acoustic wave sensor device. With the sensor disclosed by the invention adopted, defects such as the poor structuralstability, short service life, axial deformation of a cantilever beam are avoided; a force to be tested is increased according to a lever principle, and therefore, the structure sensitivity of the sensor is high, the detection threshold value of the sensor is low; and an acceleration direction can be detected. The sensor is convenient to install, high in detection precision, and has a bright application prospect.

A safety door detection device based on light ionization detector is prepared as connecting air inlet of preheating air chamber to air outlet of vacuum pump and connecting air inlet of preheating air chamber to air inlet pipe of light ionization detector through solenoid valve; using power supply system to provide power for vacuum pump, preheating air chamber, solenoid valve, light ionization detector and digital display.