Abstract:
The present invention provides a method for a method for measuring the properties of liquid based on a quartz crystal microbalance sensor, which employs two measurements to obtain two frequency shifts of the QCM sensor induced by two different volume of the sample liquid. The present invention creatively established the relationship between the density and viscosity of sample liquid and the frequency shifts of QCM sensor. With present invention, the density and viscosity of sample liquid can be obtained through two frequency shifts. Comparing to the conventional liquid property measurement. The measuring procedure of present invention are more simple, and the measuring results are more accurate. Moreover, the present invention consumes less volume of sample liquid, and has the features such as online, real time and quantitative.
Abstract:
A vanadium oxide thermo-sensitive film material with a high temperature coefficient of resistance (TCR) contains a rare earth element of Yttrium serving as a dopant in a preparation process. The vanadium oxide thermo-sensitive film material includes a substrate and a yttrium-doped vanadium oxide film layer. The yttrium-doped vanadium oxide film layer includes three elements of vanadium, oxygen and yttrium, wherein the atomic concentration of yttrium is at a range of 1%-8%, the atomic concentration of vanadium is at a range of 20-40% and the residue is oxygen. The method for preparing the vanadium oxide thermo-sensitive film material with high TCR includes a reactive magnetron sputtering method using a low-concentration yttrium-vanadium alloy target as a sputtering source or a reactive magnetron co-sputtering method using dual targets including a high-concentration yttrium-vanadium alloy target and a pure vanadium target as a co-sputtering source.
Abstract:
The present disclosure discloses a multipath current source switching device, including a switching control unit, N current paths, and N loads. Each current path is formed by a constant current source circuit and a switching circuit. One terminal of a first load is coupled to a load power supply, and the other terminal of the first load is coupled to an output terminal of a constant current source circuit of a first current path and one terminal of a second load; one terminal of an ith load is coupled to the other terminal of an (i−1)th load and an output terminal of a constant current source circuit of an ith current path; and the switching control unit controls an output current of a corresponding constant current source circuit through a corresponding switching circuit. When the circuits are switched, an output voltage of a switching circuit of a current path to be switched off is decreased to zero according to a preset voltage variation quantity, and an output voltage of a switching circuit of a current path to be switched on is increased to a highest operating voltage according to the preset voltage variation quantity, such that a current on a load does not exceed a preset current and is not zero during switching. N is an integer not less than 2, and i is equal to 2, 3, 4, . . . , N.
Abstract:
An asymmetric waveform pulse generator comprises a metallic oxide semiconductor field effect transistor (MOSFET) bridge circuit, which includes a plurality of MOSFETs for inverting high voltage DC voltage to asymmetric waveform pulses. The asymmetric waveform pulse generator further comprises a pulse-width modulating (PWM) circuit for generating PWM signals, and a plurality of isolation driving circuits corresponding to the plurality of MOSFETs, for controlling switching on/off of the plurality of MOSFETs in the MOSFET bridge circuit based on the PWM signals generated by the PWM circuit. Each of the isolation driving circuits comprises an isolation transformer for isolating the MOSFET bridge circuit from the PWM circuit. A FAIMS ion detector employing the asymmetric waveform pulse generator is also disclosed.
Abstract:
For the signal under acquisition which varies monotonically before and after the trigger time, a method for full-digital random sampling employs first sampled data before the trigger time and first sampled data after the trigger time to fit a curve, and obtains an intersection point of triggering level and the fitted curve, then, calculates the time interval between sampled data after the trigger time and the intersection point in the end, reconstructs the original signal, i.e. the signal under acquisition by a time interval of each acquisition. Thus, an analog trigger circuit and a time measurement circuit of conventional random sampling system can be eliminated, that simplifies the circuit design of data acquisition system and decreases its hardware complexity. Moreover, the higher sampling rate for the signal under acquisition is attained, and more waveform details are obtained.
Abstract:
A pipelined processor including a combinational logic of several stages, a voltage regulator, a counter, a comparator, and a plurality of stage registers. Each stage register is disposed between two adjacent stages of the combinational logic. The stage register includes a flip-flop, a latch, an XOR gate, and a MUX module. When the high level of a register clock is coming, the flip-flop latches first data at the rising edge, and the latch receives second data during the high level. The data latched by the flip-flop and the latch respectively are compared by the XOR gate. If they are same, the output Error of the XOR gate is low level, and the output of the flip-flop is delivered to the next stage. Otherwise, the output Error of the XOR gate is high level, and the output of the latch is delivered to the next stage.
Abstract:
An integrated structure of an ultrafast response hydrogen sensor includes: a gas path chamber; a gas extractor fixed to a gas inlet of the gas path chamber; and a first hydrogen sensor and a second hydrogen sensor provided inside the gas path chamber; wherein the gas extractor is located in an identical straight line with the first hydrogen sensor and the second hydrogen sensor; the first hydrogen sensor and the second hydrogen sensor each have an Port A and a Port B, and DC voltage is applied to the Port A of the first hydrogen sensor and the Port B of the second hydrogen sensor, and the Port B of the first hydrogen sensor is connected to the Port A of the second hydrogen sensor to form a shared port, and the shared port serves as a voltage output port.
Abstract:
Provided herein is a method for preparing indium oxide nanorods, comprising the following steps: S1: placing indium oxide powder at a central temperature control area of a tube furnace, and then placing a cleaned silicon wafer downstream from the indium oxide powder; S2: evacuating inside the tube furnace, and then continuing to introduce argon gas; and S3: adjusting a program to heat up the central temperature control area of the tube furnace and maintaining it at a temperature, and then naturally cooling to obtain a indium oxide nanorods grown on the surface of the silicon wafer.
Abstract:
The present disclosure discloses a three-dimensional inversion method of airborne transient electromagnetics based on deep learning. The method of the present disclosure proposes two strategies that focus on training datasets, to improve the performance of deep learning models, including divide and conquer strategy and random models generating. Through a large of reasonable structural models, appropriate network setups, a more generalized result can be obtained through our proposed U-Net framework, which has been demonstrated to be effective on both synthetic and field data. This scheme can realize the rapid prospecting of three-dimensional resistivity structure in large-area target region, and solve the problem of low efficiency of traditional three-dimensional inversion calculation of ATEM and poor migration ability of three-dimensional inversion based on deep learning developed by predecessors.
Abstract:
The present disclosure provides a GaAs monolithic integrated terahertz low-noise communication system transceiver front-end, including an intermediate frequency circuit and a terahertz circuit. The terahertz circuit includes a local oscillator frequency tripler, a local oscillator unidirectional 3 dB filter coupler, a radio frequency 180° filter coupler, and two terahertz GaAs monolithic integrated subharmonic mixers. The local oscillator unidirectional 3 dB filter coupler and the radio frequency 180° filter coupler each include one ring-cylindrical resonant cavity and four rectangular waveguides. The ring-cylindrical resonant cavity is divided into four rectangular waveguides which are correspondingly connected to the four sector-annular resonant cavities, respectively. The present disclosure suppresses the local oscillator noise by adopting a local oscillator unidirectional 3 dB filter coupler and a radio frequency 180° filter coupler with both coupling and filtering functions, thereby achieving a low local oscillator noise transceiver front-end.