Guangdong Ocean University

The present disclosure provides a parabolic tooth trace gear mechanism with a combined tooth profile of an end face circular arc and a parabola, which belongs to the field of gear transmission. The parabolic tooth trace gear mechanism with the combined tooth profile of the end face circular arc and the parabola includes a small wheel and a big wheel geared externally with parallel axes, tooth surfaces of the small wheel and the big wheel both have a parabolic tooth trace structure, and both are formed by the motion of a combined tooth profile curve of an end face along a contact point, contact lines are all parabolas after being unfolded along a cylindrical surface, and the parabola is determined by a meshing line parameter equation and basic design parameters such as a coincidence degree, the number of teeth, a transmission ratio and the like. When correctly installed, at least one pair of gear teeth of the small wheel and the big wheel, implement pure rolling meshing contact at a node. The small wheel and the big wheel rotate when being driven by a driver to implement transmission between two shafts. The parabolic tooth trace gear mechanism with the combined tooth profile of the end face circular arc and the parabola according to the present disclosure has the advantages of a low frictional wear, a high transmission efficiency, a large single-stage transmission ratio, a strong bearing capacity and the like, and can be widely applied to a transmission system design of mechanical equipment.

This present disclosure provides a method for preparing chondroitin sulfate from tilapia skull, including enzymatic hydrolyzing tilapia skull powder by Savinase 16L to obtain Savinase 16L enzymatic hydrolysate, re-enzymatic hydrolyzing the Savinase 16L enzymatic hydrolysate by 2709 alkaline protease, then separating and purificating the solution by ethanol and cetylpyridine chloride to obtain the chondroitin sulfate. The present disclosure adopts a compound enzymatic hydrolyzing method by Savinase 16L and 2709 alkaline protease to effectively achieve the efficient extraction of chondroitin sulfate of tilapia skull powder, and further achieve the purification of chondroitin sulfate by ethanol and cetylpyridine chloride, so that tilapia by-products can be utilized with high value.

A rolling gear rack mechanism with tooth profile having hyperbolic tooth line structure based on a parabolic function includes a gear and a rack. An end face tooth profile of the gear and an end face tooth profile of the rack are composed of an end face working tooth profile curve and a tooth root transition curve, and the end face tooth profile of the gear and the end face tooth profile of rack are both symmetrical left and right. The end face working tooth profile curve of the gear and the end face working tooth profile curve of the rack are parabolic, and a tooth surface of the gear and a tooth surface of the rack have a hyperbolic tooth line structure. At least one pair of gear teeth meshing points of the gear and the rack are located at nodes to achieve rolling meshing contact.

A servo reducer includes a motor gear connected to a driving motor, a support structure, a first-stage gear set, a first-stage shaft, a second-stage gear set, a second-stage shaft, a third-stage gear set, a third-stage shaft, and an output gear meshed with the third-stage gear set. The first-stage shaft, the second-stage shaft, and the third-stage shaft are mounted on the support structure. The first-stage gear set is mounted on the first-stage shaft and is meshed with the motor gear. The second-stage gear set is mounted on the second-stage shaft and is meshed with the first-stage gear set. The third-stage gear set is mounted on the third-stage shaft and is meshed with the second-stage gear set. When an external load exceeds an allowable limit of a gear strength, external load energy is converted into friction heat between the teeth and consumed, so no backlash is defined.

Disclosed are a method and system for utilizing wind energy in mariculture. The method includes performing fitting on a wind energy power time series and a historical actual wind energy power time series, obtaining a historical fitted wind energy power time series, inputting the historical fitted wind energy power time series into a wind energy power prediction model, and outputting a future wind energy power time series; inputting an obtained historical electricity consumption time series into an electricity consumption prediction model, and outputting a future electricity consumption time series; determining a future wind energy power shortage time series; and sequencing all electric devices in an offshore aquaculture platform based on priorities, obtaining an electric device sequence, and generating an electric device electricity consumption distribution strategy based on the future wind energy power shortage time series and the electric device sequence.

Disclosed in the present disclosure is a method and system for controlling and distributing wave energy in offshore aquaculture. The method includes: obtaining an aquaculture cycle of each aquaculture sub-zone of an offshore aquaculture zone, sorting remaining aquaculture cycles of the aquaculture sub-zones from small to large, and obtaining a plurality of work cycles according to sorting results; obtaining a predicted wave energy yield of a next work cycle through a preset neural network model; obtaining an importance coefficient value sorting result of each aquaculture zone through a preset recursive feature elimination (RFE) model; and adjusting operation cycles and operation power of first-type aquaculture apparatuses, second-type aquaculture apparatuses, and third-type aquaculture apparatuses in sequence according to an apparatus type of each aquaculture apparatus, the aquaculture zone where each aquaculture apparatus is located, the predicted wave energy yield, and the importance coefficient value sorting results.

The present invention relates to the field of efficient utilization of biological resources and discloses an aquatic protein pretreatment method. According to the method, an aquatic protein is pretreated by using a dense phase carbon dioxide (DPCD) technology, and conditions of the DPCD technology are that: a pressure is 5-30 MPa, a temperature is 30-60° C., and a time is 10-60 min. According to the present invention, by using the DPCD technology to pretreat the aquatic protein and specifically controlling the conditions (pressure, temperature, and time) of the technology, not only is the degree of hydrolysis of the aquatic protein treated by means of the DPCD technology remarkably increased, but also the flavor (taste and smell) of an enzymatic hydrolysate of the aquatic product is remarkably improved, and a utilization rate of protein resources is remarkably increased.

An identification method of position-independent geometric errors in rotary axes of five-axis machine tools based on ballbar, in which a center of a cutter ball is installed at an intersection point of A-axis and C-axis centerlines; a workpiece ball is installed with an offset in X and Y directions; the two axes are controlled to move independently to switch between two measurement modes under a single installation mode; and through three installations, eight position-independent geometric errors of the two axes are identified. In the method, coordinates of the workpiece ball are calculated through inverse matrix transformation, so as to establish initial coordinates of the two balls in a reference coordinate system; a comprehensive rod-length model including installation errors is constructed based on homogeneous coordinate transformation; and simulation analysis is conducted to compare identified values with preset values.

The present disclosure provides a parabolic tooth trace gear mechanism with a combined tooth profile of an end face circular arc and a parabola, which belongs to the field of gear transmission. The parabolic tooth trace gear mechanism with the combined tooth profile of the end face circular arc and the parabola includes a small wheel and a big wheel geared externally with parallel axes, tooth surfaces of the small wheel and the big wheel both have a parabolic tooth trace structure, and both are formed by the motion of a combined tooth profile curve of an end face along a contact point, contact lines are all parabolas after being unfolded along a cylindrical surface, and the parabola is determined by a meshing line parameter equation and basic design parameters such as a coincidence degree, the number of teeth, a transmission ratio and the like. When correctly installed, at least one pair of gear teeth of the small wheel and the big wheel, implement pure rolling meshing contact at a node. The small wheel and the big wheel rotate when being driven by a driver to implement transmission between two shafts. The parabolic tooth trace gear mechanism with the combined tooth profile of the end face circular arc and the parabola according to the present disclosure has the advantages of a low frictional wear, a high transmission efficiency, a large single-stage transmission ratio, a strong bearing capacity and the like, and can be widely applied to a transmission system design of mechanical equipment.

The present disclosure provides a self-powered, portable, and high-throughput Surface-Enhanced Raman Spectroscopy (SERS) biosensing platform, including: a handheld Raman spectrometer, a friction nanogenerator, a superhydrophobic metal substrate, and a high-voltage electrode array. The friction nanogenerator has one end connected to the superhydrophobic metal substrate, and the other end connected to the high-voltage electrode array. The high-voltage electrode array is disposed above the superhydrophobic metal substrate. The friction nanogenerator is used for providing an alternating voltage to the high-voltage electrode array. The high-voltage electrode array is used for oscillating droplets on the superhydrophobic metal substrate according to the alternating voltage, and generating an eddy current to heat the droplets and accelerate evaporation of the droplets. The handheld Raman spectrometer is used for detecting the enriched droplets, to obtain a SERS spectrum of an analyte.