1749 results about "Ice formation" patented technology

The invention relates to an ice crystal evaporator and an ice crystal water cooling device producing from the same, belonging to the technical field of refrigeration. The ice crystal evaporator is characterized in that a liquid inlet channel is formed by an evaporator tube, a liquid inlet and a liquid outlet in a tubular casing; and the outer channel of the evaporator tube of the tubular casing is divided into more than one S-shaped channel forming a water return channel through a water inlet of a water divider and a water outlet of a water collector. The ice crystal water cooling device is characterized in that the return air inlet of the ice crystal evaporator is communicated with a compressor, a condenser, a liquid feeding valve, a dry filter, a liquid feeding electromagnetic valve anda thermostatic expansion valve in sequence, and then is communicated with the liquid inlet of the ice crystal evaporator; a cooling water inlet / outlet of the condenser is connected with a cooling tower in series; and a water inlet / outlet of the ice crystal evaporator is communicated with a water circulating pump and an ice crystal energy storage tank in series. The invention has the advantages ofhigh cooling efficiency, no icing and low cooling temperature and is suitable for production of energy storage central air-conditioning, marine fishing, seafood processing, fruit, vegetable or meat processing, and the like; the cooled medium is municipal water.

The invention relates to the technical field of new energy, in particular to a fan blade composite deicing system and method.The fan blade composite deicing system comprises a sensing layer, a decision-making layer, an execution layer and a feedback layer, and the decision-making layer comprises a graph neural network ice type recognition module, a CFD-icing coupling simulation module, a health management module and an energy consumption scheduling algorithm unit; the execution layer comprises a control unit and an execution unit, the control unit comprises a dynamic partition heating controller and a self-adaptive vibration controller, and the execution unit comprises an electric heating system and a vibration deicing system; compared with the prior art that a single deicing mode is usually adopted, and the adaptability to different ice type physical characteristics is poor, the scheme adopts a differential execution strategy, and partition electric heating control is carried out on different chord length areas of the blade based on the ice type recognition result; and high-frequency piezoelectric standing wave vibration is adopted for glaze ice, low-frequency eccentric wheel vibration is adopted for glaze ice, and the beneficial effects that the deicing efficiency is remarkably improved, invalid energy consumption is reduced, and damage to blades is reduced are achieved.

The invention relates to the technical field of tunnel disaster identification, in particular to a tunnel portal icing disaster identification and prediction method based on a multi-modal data fusion technology. According to the technical scheme, the method comprises the steps of multi-source data acquisition, heterogeneous data processing, feature level fusion, disaster recognition, space-time prediction and dynamic early warning. According to the invention, a multi-modal sensor is deployed to collect tunnel portal temperature, space structure and environmental parameters, intelligent processing and multi-stage feature fusion are carried out, ice layer distribution identification, icing trend detection and time-space prediction are realized by using a deep network, an ice melting device is dynamically activated in combination with a graded early warning mechanism, and vehicle early warning is linked. A sensing, analysis, prediction, disposal and calibration closed loop is formed, the accuracy of ice coagulation disaster detection, the prospective performance of prediction and the intelligence of disposal are remarkably improved, and the tunnel traffic safety and the long-term robustness of the system are guaranteed.

The invention relates to the technical field of fan blade deicing, and discloses an intelligent temperature control type fan blade electric heating deicing control system and method, and the system comprises a meteorological sensing module which is used for collecting the environment temperature, humidity, wind speed and rainfall type; the blade state monitoring module is used for acquiring blade surface temperature distribution and ice layer thickness data; the dynamic decision-making module is used for generating a partition heating instruction based on the data of the weather sensing module and the blade state monitoring module; the temperature control execution module is used for converting the instruction into a gradient signal; the heating array module is used for executing electric heating deicing operation in the blade surface subareas; and the energy coordination module is used for dynamically constraining the total power of the system. The meteorological sensing module and the blade state monitoring module are integrated through the system, real-time collection and fusion of multi-source data of blade surrounding environment parameters and the thickness of an ice layer are achieved through the design, comprehensiveness and accuracy of icing monitoring are improved, a reliable basis is provided for dynamic decision making, and therefore the response capacity and early warning precision of the system to icing risks are improved.

The invention belongs to the technical field of bone tissue low-temperature storage, and particularly relates to a deep low-temperature storage method for retaining bone tissue activity, which comprises the following steps: A1, acquiring a bone tissue sample, transporting the bone tissue sample to a treatment center in a cold chain manner, pre-treating the bone tissue, cleaning periosteum, putting the bone tissue sample into negative-pressure ultrasonic purified water for cleaning, inactivating with alcohol, flushing with sterile PBS (Phosphate Buffer Solution), and cleaning the bone tissue; a2, preparing a cryoprotectant, immersing the bone tissue into the cryoprotectant, and maintaining the temperature through an ice-water bath; a3, after the cryoprotectant enters the bone tissue, the bone tissue is placed in pre-freezing equipment, and the bone tissue is pre-frozen; a4, the pre-frozen bone tissue is taken out and then put into a liquid nitrogen storage container, and low-temperature storage of the bone tissue is started; through the treatment of the series of methods, the formation of ice crystals can be reduced, and the icing of water in cells and tissues is promoted to become more uniform and smaller, so that the damage to bone tissue cells is reduced.

The invention belongs to the technical field of cell cryopreservation, and relates to a cryopreservation method based on ultrasonic ice planting. In the method, the nucleation temperature of ice planting is less than-9 DEG C, and the cooling rate from nucleation to icing is less than 5 DEG C / min. Compared with the prior art, the method has the advantages that the time required for cryopreservation of the cells is remarkably shortened, meanwhile, damage to the cells caused by ice crystals generated in the cooling process is reduced, and the problem that an existing cell cryopreservation cooling method cannot meet the nucleation and freezing uniformity of a cell solution in the cooling process is solved.

The invention relates to an anti-icing-deicing composite surface and a preparation method thereof, and belongs to the field of anti-icing and deicing. The surface comprises a porous material substrate, a super-hydrophobic / hydrophobic lubricating fluid top microstructure and a hydrophobic / hydrophilic lubricating fluid internal microstructure, wherein the super-hydrophobic / hydrophobic lubricating fluid top microstructure and the hydrophobic / hydrophilic lubricating fluid internal microstructure are coupled to the surface of the porous material substrate; lubricating fluid is injected into the surface of the hydrophobic / hydrophilic lubricating fluid internal microstructure; the super-hydrophobic / hydrophobic lubricating fluid top microstructure is located on the surfaces of a plurality of columnar bodies arranged on the porous material substrate in an array mode, namely, the super-hydrophobic / hydrophobic lubricating fluid top microstructure has the super-hydrophobic characteristic to water and lubricating fluid. And the hydrophobic / lubricating fluid-loving internal microstructures are also arranged in the array form, surround the root of each cylindrical object, and have the characteristics of lubricating fluid loving and hydrophobicity. The surface can have anti-icing / ice-dredging properties of super-hydrophobic and super-smooth properties at the same time, that is, the surface can have excellent anti-icing properties of a super-hydrophobic surface, and can also be ice-dredging like a super-smooth surface after the surface is iced, so that ice is easier to remove.

The invention discloses an alpine region-based double-curvature arch dam aeration ice-melting anti-icing device, and relates to the technical field of anti-icing, the alpine region-based double-curvature arch dam aeration ice-melting anti-icing device comprises a double-curvature arch dam body, a lifting structure, an aeration anti-icing structure, a PLC controller, a temperature sensor and a liquid level sensor are arranged on the outer convex curved surface side of the double-curvature arch dam body, and the aeration anti-icing structure comprises a plurality of fourth connecting pipes; the bottoms of the outer sides of the fourth connecting pipes are fixedly connected with a plurality of pressure release valves, and the bottoms of the pressure release valves are fixedly connected with bubble generators, so that along with the rise of the internal air pressure of the fourth connecting pipes, the air flow bursts through the pressure release valves and then is discharged through the bubble generators, and a large number of bubbles are generated; and in the process that the bubbles move towards the water surface, the water surface is stirred, the water surface is prevented from being frozen, the anti-freezing effect on the upstream side of the hyperbolic arch dam body is comprehensively achieved, and damage to the structure of the upstream side of the hyperbolic arch dam body caused by freezing is reduced.

The invention discloses an existing wind power blade electrothermal film deicing control method based on big data, and relates to the technical field of wind turbine generator operation control and ice prevention and removal. Frost ice / glaze ice probability output by an ice type discrimination model does not only give an alarm any more, but is directly converted into an increase / decrease coefficient constrained by boundary and monotonicity; energy can be fully put in a glaze ice scene, and overheating and over-consumption can be avoided in a frost ice scene; according to the method, the change trend of wind speed, temperature and relative humidity is introduced as modulation factors, the working condition of forming / turning glaze ice is responded in advance, and insufficient deicing caused by static threshold hysteresis is reduced; according to power deviation correction, a unit wind speed-power curve serves as a reference, a dead zone, segmented gain and accumulative saturation structure is adopted, on the premise of not depending on an external icing sensor, extrinsic performance of pneumatic degradation is closed into controlled quantity, sensitivity and stability are considered, and start-stop oscillation and duration drift are reduced.

The invention discloses a short-term wind power combined prediction method and system in an icing state, and the method comprises the steps: constructing an icing label data set based on historical meteorological data and power data, and building an icing identification model; obtaining the wind speed of a fan in the station by combining with multi-source weather forecast, and constructing a fan icing growth model; based on different wind speeds, icing degrees and fan types, an icing fan CFD simulation model is constructed, and a wind speed power correction coefficient table under fan icing is constructed through simulation calculation; establishing at least two power prediction models based on different machine learning models, and constructing and training a short-term wind power combined prediction model; and calculating the hourly power correction coefficient of the icing station by combining the wind speed-power correction coefficient table under the icing of the fan through the icing identification and icing growth model, and calculating the power prediction value under the icing state based on the short-term wind power combination prediction model. According to the method, the accuracy of icing fan power prediction can be improved, and the station output can be obtained more efficiently and accurately.

The invention provides an intelligent fresh-keeping method and system for non-crystallization frozen storage of meat, and relates to the technical field of intelligent fresh keeping of meat products, and the method comprises the following steps: obtaining a non-crystallization temperature zone of frozen storage of the meat products; inputting the initial freshness parameter value, the target shelf life and the comprehensive quality evaluation threshold value into an amorphous frozen storage critical temperature decision model, and outputting an amorphous frozen storage critical temperature; the non-crystallization freezing critical temperature is the highest temperature when the meat product reaches the target shelf life; based on the principle that the temperature is lower than or equal to the non-crystallization freezing temperature and is higher than or equal to the lower limit temperature of the non-crystallization temperature zone, determining the non-crystallization freezing temperature; determining an electric field parameter corresponding to the non-crystallization freezing temperature according to the non-crystallization freezing temperature and the non-crystallization freezing critical temperature data set; and performing electric field assisted storage on the meat based on the non-crystallization freezing storage temperature and the electric field parameters. According to the invention, the traditional freezing and cold storage temperature zone boundary is broken through, the quality deterioration of meat caused by freezing is avoided, and the intelligent preservation of freezing quality chilled fresh-keeping is realized.

The present application provides an anti-icing sensor, which belongs to the technical field of detection equipment, and specifically includes a sensitive element, a mounting seat, and a sensor housing connected to the mounting seat. A temperature measuring end is provided on the side of the sensor housing away from the mounting seat, and an anti-icing structure is provided on the temperature measuring end. The sensitive element is connected to the sensor housing and is located on the leeward side of the temperature measuring end. The anti-icing structure is configured as a wedge-shaped structure, and the wedge-shaped structure includes a windward end and a leeward end. The cross-sections of the windward end and the leeward end parallel to the airflow direction are both isosceles triangles, and the first vertex angle of the isosceles triangle of the windward end faces the incoming flow direction, and the second vertex angle of the isosceles triangle of the leeward end faces away from the incoming flow direction, and the angle of the first vertex angle is greater than the angle of the second vertex angle. Through the processing scheme of the present application, the situation where the temperature measuring function of the sensor fails due to icing of the temperature measuring end can be effectively avoided, and the test stability can be improved.

The invention discloses an environment-friendly flame-retardant medium-voltage cable, and relates to the technical field of cables, the outer side of an inner conductor is provided with a flame-retardant protection assembly, the flame-retardant protection assembly comprises flame-retardant filling bodies, the middle parts of the opposite side surfaces of the adjacent flame-retardant filling bodies are provided with supporting grooves, and arc-shaped spring plates are adhered to the interiors of the supporting grooves. The outer side of the cable is extruded and collided, the impact force is attenuated layer by layer, the situation that the cable is damaged due to collision and impact is reduced, when the outer side of the cable is frozen, the heating wire emits heat, and the cable is prevented from being damaged. When the cable is deiced, the inflatable strip outside the insulating middle layer is uniformly heated, the outer insulating layer is pushed to bulge, and the ice layer outside is jacked open, so that the ice layer is broken and falls off, and compared with the conventional deicing method which only depends on heating, the energy consumption is lower, the cable is environment-friendly and energy-saving, the deicing effect is better, and the cable is more favorably protected.

The invention relates to the technical field of flow field temperature testing, in particular to a gas phase temperature measuring probe for a high-speed low-temperature cloud field and a design method and application of the gas phase temperature measuring probe. The design method of the gas phase temperature measurement probe for the high-speed low-temperature cloud field comprises the following steps: designing a temperature measurement probe configuration on the basis of a backward temperature measurement probe configuration in combination with a backward step two-phase flow theory in the backward temperature measurement probe configuration and working conditions of the high-speed low-temperature cloud field; secondly, two-phase flow simulation and suction flow simulation are carried out based on the temperature measurement probe configuration, and suction flow is designed; thirdly, icing numerical simulation is carried out, and two-phase flow simulation is carried out; and finally, analyzing the simulation result of the near-wall flow field change of the iced temperature measurement probe configuration and the simulation result of the gas-liquid flow characteristics, and if no liquid drop is monitored at the detection position of the temperature sensing element in the iced temperature measurement probe configuration, completing the design; otherwise, repeating the above steps until no liquid drop is monitored at the detection position of the temperature sensing element in the frozen temperature measurement probe configuration.

The invention relates to the technical field of ice and snow environment simulation, and discloses an ice and snow environment simulation test method based on multi-field coupling. The method comprises the following steps: collecting a dynamic multi-field data set in a target ice and snow environment, wherein the dynamic multi-field data set covers a periodic temperature change sequence, a relative humidity fluctuation sequence and surface ice layer thickness real-time monitoring data; carrying out multi-physics field coupling numerical simulation processing to generate coupling field distribution characteristics including an axial heat conduction coefficient gradient, a radial fluid velocity cumulant and a tangential ice layer stress fluctuation coefficient; calling a pre-configured ice and snow growth simulation model to execute ice layer evolution analysis to obtain an ice layer growth rate prediction value and a high-risk icing area position identifier; performing environment dynamic compensation correction on the ice layer growth rate prediction value by using the correlation characteristic of the relative humidity fluctuation sequence and the material heat capacity attribute; based on the high-risk icing area position identification, scientific guidance is provided for related protection in the ice and snow environment.

The invention discloses a tunnel dew formation and icing rapid monitoring method and system based on a space-time phase change cooperation mechanism, and relates to the technical field of tunnel engineering safety monitoring and freeze injury prevention and control. Establishing a tunnel geometric model and a heat-humidity-turbulence multi-field coupling physical model; synchronously acquiring heat and humidity physical property parameters and outdoor hourly meteorological parameters; taking the outdoor hourly meteorological parameters as Dirichlet boundary conditions and initial conditions of a heat-humidity-turbulence multi-field coupling physical model; determining a heat and humidity exchange coupling process of the tunnel wall surface and the internal environment, and defining heat and humidity transfer parameters under an unsteady state boundary; performing discretization processing on the tunnel geometric model by adopting a grid division strategy; by setting a dew point temperature threshold value and an icing temperature threshold value, a condensation risk area is judged, dynamic changes of the thickness of an ice layer are quantified, and monitoring of tunnel condensation and icing is achieved. The method can effectively reflect the distribution rule of multiple physical fields on the surface and in the tunnel in any time, accurately judge the risk area and quantify the thickness of the ice layer.

The invention discloses a fan blade icing prediction method and device and a medium, and relates to the technical field of equipment monitoring, and the method comprises the steps: obtaining historical meteorological data, blade tip speed, pitch angle and historical icing data, and taking the data as real samples; performing data expansion on the real sample by using the generative adversarial network model to obtain a generated sample; the real samples and the generated samples form a training sample set, the training sample set is used for training the long-short-term memory neural network, and a fan blade icing prediction model is obtained to predict the icing condition of the fan blade. According to the method, the blade tip speed and the pitch angle which reflect relative motion of the blade and the supercooled liquid drop are added in training data, a prediction model obtained through training comprises icing phase change characteristics and relative motion characteristics of icing of a rotating object, description of the icing process of the fan blade is more accurate, and prediction is more accurate; the adversarial generative network model is adopted to expand the training sample set of the prediction model, the problem of insufficient real samples is solved, and the prediction accuracy is further improved.

The invention relates to the technical field of power maintenance, and discloses a power transmission and transformation line installation and maintenance device which comprises an installation base, one end of the installation base is rotationally connected with a first rotating wheel, the other end of the installation base is rotationally connected with a second rotating wheel, and a servo motor is fixed to the installation base. A motor shaft of the servo motor is in transmission connection with one end of the first rotating wheel, a servo electric cylinder is fixed on the mounting seat, the end part of the servo electric cylinder is in sliding connection with a top cover, a telescopic shaft of the servo electric cylinder is provided with an eleventh spring, and one end of the eleventh spring is fixedly connected with the top cover; the purpose that the collision assembly drives the knocking block to continuously impact the frozen power transmission and transformation line can be achieved, ice blocks on the power transmission and transformation line can fall off when being impacted, the amount of the ice blocks on the power transmission and transformation line can be reduced, the load can be reduced, the wind resistance can be reduced, and the maintenance effect on the power transmission and transformation line can be improved.

The invention relates to the technical field of anti-icing, in particular to a photo-thermal phase change energy storage super-hydrophobic all-weather anti-icing composite coating and a preparation method thereof. Comprising the following steps: S1, preparing a phase change microcapsule of chitosan coated paraffin through a single coacervation method; s2, modifying a carbon nano tube, and adding the modified carbon nano tube into the suspension of the phase change microcapsule to form a composite microcapsule; and S3, uniformly mixing the composite microcapsule with organic silicon. Compared with the prior art, by combining the photo-thermal and super-hydrophobic characteristics and the energy storage effect of the phase change microcapsules, the effect of effectively delaying icing can be achieved, the ice resistance and deicing efficiency is high, the photo-thermal conversion performance is good, the super-hydrophobic performance is good, and surface ice prevention and deicing under the extreme weather condition can be achieved; and the coating can keep effective anti-icing and deicing functions under low-temperature and high-humidity conditions. 2, the nanoparticles are grafted to the surface of the chitosan phase change microcapsule to form an organic-inorganic composite phase change microcapsule, and the flexibility of organic substances and the stability of inorganic materials are combined;

The invention relates to the technical field of road ice melting, and discloses a road ice melting implementation system and method. The system comprises a meteorological monitoring platform, a snow-melting agent spraying platform and a management and control platform, the method comprises the following steps: firstly, collecting meteorological data and monitoring a road surface state to obtain an initial road ice melting data set, and then carrying out anomaly detection and filling missing data; establishing a road ice melting prediction model based on the neural network, predicting whether the road is iced or not, and outputting a road icing result; then ice melting work is carried out, an enhanced hawk optimization algorithm is introduced to optimize spraying parameters in the ice melting work, and a road ice melting implementation strategy is generated; and finally, adjusting a road ice melting implementation strategy, and establishing a snow melting environment coupling model and an alarm mechanism. By analyzing and processing the road ice melting data, the purpose of implementing road ice melting is achieved, and the method is objective and accurate.

The utility model relates to the field of anti-freezing devices, in particular to a gate anti-freezing device which comprises a bottom plate, a gate body is movably installed at the upper end of the bottom plate, a main beam is fixedly installed at the upper end of the gate body, water pumps are fixedly installed on the two sides of the upper surface of the main beam, and turbulent flow mechanisms are fixedly installed at the upper ends of the water pumps. A boss is fixedly installed on the rear surface of the main beam, and a fixed base is fixedly installed on the upper surface, located under the boss, of the bottom plate. A turbulent flow mechanism is adopted, a water pump conveys water flow on the side with the high water level of a reservoir into a drainage main pipe through a water suction pipe, water flow scouring is conducted on the two sides of the gate body through spray pipes, and the water body is kept moving to avoid icing. When the air temperature is too low, the gate body is frozen, the ice breaking mechanism slidably installed at the lower end of the main beam is used for breaking, the floating barrels arranged on the two sides of the floating plate guarantee that the ice breaking mechanism is kept at the upper end of the water surface, the influence of the water surface height is avoided, and ice breaking operation can be continuously conducted.

The small seawater freezing desalination crystallizer comprises an upper end bearing, an upper end cover, a rotating shaft, a lower end cover, a lower end bearing, a fixed pipe plate, a shell, an outer layer crystallization pipe, an inner layer crystallization pipe, an annular plate, an inner scraper, an outer scraper, a knife rest, a refrigerant inlet pipe, a refrigerant outlet pipe, a conveying pipe, a water inlet pipe, a first outlet ice water pipe, a second outlet ice water pipe and a variable frequency motor. According to the device, freezing crystallization desalination of seawater is completed mainly through continuous indirect heat exchange between seawater in the inner-layer crystallization pipe and seawater outside the outer-layer crystallization pipe and refrigerants between the inner layer and the outer layer of the crystallization pipe, simultaneous continuous freezing of the inner layer and the outer layer of the crystallization pipe is achieved, the heat exchange area is increased, and the heat exchange efficiency is improved; and the method has a great industrial application prospect.

Systems and methods for detecting and responding to stuck vehicle doors, where the doors are stuck due to ice formation on the vehicle. In particular, systems and methods are provided to utilize diagnostic signals from the vehicle door motor controller to automate the process of detecting stuck doors due to ice formation. Vehicle internal systems can be used to attempt to unstick a stuck door without manual intervention. Additionally, vehicle routing can be used to unstick a stuck door without manual intervention. For example, a vehicle can be routed to a facility where the temperature is above freezing so any ice formation on the vehicle will melt. Vehicle routing can also be used to route the vehicle to a facility for service to unstick the stuck door.

The invention provides a three-dimensional icing rapid prediction method based on multi-fidelity data fusion and a neural network. The method comprises the steps of obtaining a simulated ice shape two-dimensional slice image under a first target icing working condition; inputting the simulated ice-shaped two-dimensional slice image data into a pre-trained first target neural network, and predicting ice-shaped two-dimensional slice images of different spanwise positions of the wing under a first target icing condition, the first target neural network is obtained by training according to the simulated ice shape two-dimensional slice image and a test ice shape two-dimensional slice image obtained by an icing wind tunnel test; and performing three-dimensional reconstruction on the ice-shaped two-dimensional section images at different spanwise positions to obtain a predicted wing icing three-dimensional geometrical shape. According to the method, the neural network is used for extracting main features of the icing form, and rapid prediction and reconstruction of the three-dimensional icing form are achieved. Through multi-fidelity data fusion, prediction result precision can be improved, calculation complexity can be reduced, and icing prediction precision and real-time performance can be improved.

The carbon dioxide unloading system comprises a liquid carbon dioxide storage tank, a heater, an unloading pump, a receiving tank, a plurality of pipelines and a control valve, an outlet of the liquid carbon dioxide storage tank is divided into a first pipeline and a second pipeline, the first pipeline is communicated with the heater, and the second pipeline is communicated with the receiving tank. The second pipeline is communicated to a first inlet of the receiving tank through a fifth control valve; the first pipeline is provided with a first control valve before entering the heater; the carbon dioxide outlet end of the heater is divided into a third pipeline and a fourth pipeline after passing through the second control valve; the third pipeline is provided with a third control valve and communicated with a second inlet of the receiving tank, and the fourth pipeline passes through an eighth control valve and then returns to the liquid carbon dioxide storage tank; the unloading system is provided with at least one pipeline leading to the atmosphere. Through the perfect unloading process flow design, the potential safety hazards that water is frozen, carbon dioxide forms dry ice, the pressure in the unloading system is too high and the like are properly solved, and the unloading system can operate safely and stably.

The invention relates to the technical field of synthesis and preparation of nano materials, in particular to a method for preparing tin dioxide powder, which comprises the following steps: S1, preparing a 0.1-5 mol / L tin salt solution, adding a compound additive into the tin salt solution, and carrying out ball milling treatment after ultrasonic dispersion to obtain a pretreated tin salt solution; s2, freezing and freezing the pretreated tin salt solution in an ultralow-temperature environment to obtain a frozen sample; s3, transferring the frozen sample into a vacuum freeze dryer for dehydration treatment to obtain solid powder; and S4, carrying out high-temperature calcination on the solid powder to obtain tin dioxide powder. Zero sewage discharge is achieved in the preparation process, the problem of sewage discharge and treatment of traditional liquid-phase powder preparation is solved, meanwhile, the phenomenon of sintering agglomeration accompanied by traditional solid-phase calcination can be avoided, high-quality superfine tin dioxide powder preparation is achieved, the method is simple and safe in process, and industrial large-scale production and preparation are easy to achieve.

A low-temperature ball valve packing sealing structure and a low-temperature ball valve comprise a valve rod heightening support arranged on the outer side of a valve rod, a packing box is arranged on the valve rod heightening support, packing is arranged in the packing box, and the low-temperature ball valve packing sealing structure further comprises a freezing structure arranged in the packing box at the bottom of the packing. The freezing structure can be frozen and expanded when making contact with a low-temperature medium leaked due to failure of the lip-shaped sealing ring, the packing is pushed to be further pre-tightened and sealed, by means of the freezing structure, when the lip-shaped sealing ring is intact, the graphite packing can still play a conventional sealing role, and the valve can also pass various fireproof tests; meanwhile, the operation torque of the valve cannot be increased for the valve, any performance of the valve cannot be affected by the freezing structure, and when the lip-shaped sealing ring loses efficacy and leaks, the freezing structure can freeze and expand when making contact with a low-temperature medium, the filler is pushed to be further pre-tightened and sealed, the sealing force is automatically increased, the filler can be automatically pre-warned, and sealing is enhanced; and the process does not need manual intervention.

The utility model discloses a large anti-freezing reverse flow type cooling tower which comprises a bottom water collecting tank, a cylindrical cooling shell is arranged on the upper surface of the bottom water collecting tank, an air duct of a trumpet-shaped structure is arranged at the upper end of the cylindrical cooling shell, a supporting column is arranged in the middle of the interior of the cylindrical cooling shell, and a fan is arranged at the upper end of the supporting column. The upper side of the cylindrical cooling shell is connected with a motor for driving a fan to rotate through a motor base, an annular water dispersing piece is arranged at the upper end of the interior of the cylindrical cooling shell, an inlet of the annular water dispersing piece is connected with an L-shaped water inlet pipe, an anti-icing device is arranged in the cylindrical cooling shell, and a filling device is arranged in the cylindrical cooling shell; sprayed water directly enters the water collecting tank and is mixed with original cold water in the water collecting tank, so that the temperature in the water tank is adjusted, and the water temperature in the water tank is ensured not to be too low on the premise of meeting temperature indexes required by process production in cooperation with starting of a cooling tower fan, so that the anti-freezing purpose is achieved.

The invention discloses efficient snow removal equipment for a vehicle and a using method, and belongs to the technical field of snow removal equipment, the efficient snow removal equipment comprises a supporting cross beam, a snow shovel hinged to the side edge of the supporting cross beam, and a compression spring installed between the outer side of the snow shovel and the top of the supporting cross beam. The ice breaking mechanism composed of the control box, the vertical rod, the supporting block, the reset spring, the first shaft rod, the protruding block and the groove is arranged at the front end of the snow shovel, the driving mechanism is used for controlling rotation of the first shaft rod, the vertical rod can be driven to ascend and descend in a reciprocating mode, ice on the road surface is broken before snow shoveling, the functionality and the snow removing effect of the device are improved, and the practicability is high. And in addition, a conical block is hinged to the bottom end of the vertical rod and can rotate in the direction of the snow shovel, and reset of the conical block is controlled through a tension spring, so that after ice breaking, along with continuous movement of the vehicle, the conical block can apply certain thrust to broken ice blocks and loosen the broken ice blocks, resistance generated when the vehicle moves forwards cannot be increased, and practicability is higher.

The utility model relates to the technical field of air conditioner heat pumps, in particular to an outdoor unit and heating and ventilation equipment. The outdoor unit comprises a shell assembly, an air inlet assembly and an air outlet assembly, wherein a containing cavity is defined by the shell assembly; the heat exchanger is arranged in the containing cavity; the water pan assembly is connected with the shell assembly, a water receiving part and a water accumulating part which are communicated are defined by the water pan assembly, the water receiving part is located in the containing cavity and arranged below the heat exchanger, the water receiving part is used for guiding condensate water falling from the heat exchanger to flow into the water accumulating part, and the water accumulating part is located outside the containing cavity and provided with a drainage hole. According to the outdoor unit, the water accumulation part is arranged outside the containing cavity, maintenance personnel can observe the water accumulation part visually and find the icing condition of the water accumulation part in time, ice residues, ice layers and the like in the water accumulation part can be removed without disassembling the shell of the outdoor unit, maintenance is easy, the ice layers can be prevented from blocking the drainage holes, and the service life of the outdoor unit is prolonged. It is ensured that the outdoor unit effectively discharges condensate water.