99results about How to "Realize controllable" patented technology

The invention discloses a controller for determining a network state based on an SDN (Software Defined Networking) and a determination method thereof. The controller comprises a state updating module, a calculation module, an execution module, a flow management module and an evaluation module, wherein the state updating module is used for updating through a state and a path calculated by the calculation module; the calculation module is used for calculating a current network resource state N; the execution module is used for setting rules according to the path calculated by the calculation module and writing the path into a flow meter; the flow management module is used for carrying out congestion avoidance, flow supervision and shaping; and the evaluation module is used for carrying out synthetic judgment according to the current network resource state N calculated by the calculation module and QoS (Quality of Service) requirements of an application when receiving the application transmitted by a switch. According to the controller, the network state can be accurately controlled, a forwarding plane is precisely controlled, a 'Q+X' resource distribution mode is proposed, and the network resource is scheduled, so that the flexibility, the high efficiency, the intelligence and the optimization of a network can be realized.

An interactive digital stereoscopic sand table system is composed of a stereoscopic image generating system and a man-machine interactive system. Opengl and other 3D engines are adopted by the stereoscopic image generating system to draw the three-dimensional terrain, a human eye tracking and pointing light technology is applied, stereoscopic display without assistance is achieved, and a series of image accelerating technologies is adopted to accelerate the rendering process of an image. A three-dimensional building model is arranged in a three-dimensional terrain target area, and precise space distribution and the good visual effect are achieved. A naked eye stereoscopic displayer is formed by the stereoscopic image generating system. The man-machine interactive system controls the three-dimensional terrain scene or three-dimensional model data in the stereoscopic image generating system through gestures, and is achieved by presetting a gesture recognition interface. The corresponding gestures control the three-dimensional terrain scene or the three-dimensional model data in the stereoscopic image generating system to be enlarged or reduced or horizontally moved or rotated or to enter, and the corresponding gestures capable of distinguishing different control significances can be configured according to needs.

The invention discloses a method for profiling a spherical involute spiral bevel gear. The method is characterized by comprising the steps that S1, a mathematical model of a spherical involute spiralbevel gear pair is established; S2, a tooth surface equation of a concave surface and a convex surface of a pair of meshing gears is derived; S3, a tangent plane of the position, at the center point,of the tooth surface is established, and a plane coordinate system is established on the tangent plane; S4, a point on the tooth surface is projected to a the tangent plane, and the coordinate of theprojected point in the tangent plane coordinate system is obtained; S5, the coordinate of the projected point in the S4 is substitute to a shape correction equation to obtain the correction amount ofeach point on the tooth surface; S6, the point on the tooth surface in the S2 is shifted towards the interior of the gear teeth along the tooth surface normal vector at the point; S7, the point cloudobtained after shifting in S6 undergoes high order fitting to form a smooth surface; and S8, a shape correction three-dimensional model of the spiral bevel gear is established on the basis of the profiling tooth surface. The method has the beneficial effects that a very smooth profiling tooth surface can be obtained, full controllable shape correction is achieved, and the transmission quality of the gear pair is effectively guaranteed.

The invention discloses a permissioned blockchain constructing and controlling method based on a Chameleon hash function, wherein the method relates to the field of network security technology. The method comprises the following steps of 1, defining a blockchain control mechanism and initializing the permissioned blockchain according to the blockchain control mechanism; 2, packing transaction records of a block in the network for forming a new block, and adding the new block into the permissioned blockchain; and 3, monitoring the blocks in the permissioned blockchain according to the blockchain control mechanism, and controlling the blocks which do not accord with the blockchain control mechanism. The permissioned blockchain constructing and controlling method realizes global real-time monitoring of all nodes to malicious information and error transaction information on the block; any accessing node can report the error block to the verifying node; controlling of the whole permissionedblockchain by the verifying node is realized through constructing the permissioned blockchain; In a partially de-centering environment, controlling of the permissioned blockchain is realized. All verifying nodes perform effective modification on the blocks through calculating Chameleon hash collision and DBFT consensus, thereby realizing high safety and high controllability of the permissioned blockchain.

The invention discloses a net source coordination oriented large wind farm closed-loop control system, which comprises a plurality of groups of fans constituting a wind farm fleet, routers for connecting each group of fan into the fleet, a terminal, a power grid local information measuring unit, a centralized control platform and a conventional power plant; the constituting units are connected by field buses in the system to carry out data transmission, the terminal is used as a processing terminal of the fans and the centralized control platform and is connected with the centralized control platform through a bus adapter card, a controller of the centralized control platform is arranged near a wind farm booster station, the local measured information of a power grid needing measurement includes boost bus voltage and frequency, the controller sends out transient state active and reactive control signals according to measurement information and combing field grid transient state coordination control, the control signals are sent to each fan through rapid field buses to realize active and reactive rapid adjustment of the wind farm fleet. Compared with the prior art, the large wind farm closed-loop control system disclosed by the invention realizes wind farm closed-loop control, and solves the problem of coordination of wind energy net source used as an accessing power source in wind power integration.

The invention belongs to the technical field of novel catalytic material preparation and discloses a NiTi hydrotalcite nanosheet catalyst responding to visible light and a preparation method of the catalyst. According to the invention, NiTi hydrotalcite nanosheets are synthesized by an anti-phase microemulsion method and show excellent catalytic performance by visible light. The preparation method realizes controllability of a microemulsion environment by adjusting and controlling the proportions of a surface active agent and water; and hydrotalcite is crystallized and grows in the microemulsion and the particle size of the hydrotalcite ranges from 30 nm to 80 nm. A solvent used in the method is low in cost and simple to operate and can be recycled. The obtained hydrotalcite nanosheet catalyst has the advantages of simple synthesizing conditions, cheap raw materials and easiness in large-scale industrial production. The NiTi hydrotalcite nanosheet catalyst prepared in the invention has an excellent characteristic of responding to visible light, is five times quicker than micron-sized hydrotalcite synthetized with a traditional codeposition method in water decomposition performance by visible light, and is hopefully expected to be widely applied to the fields like solar thermal utilization, adsorption and additives.

The invention discloses a method for increasing the security of a file encryption key in a trusted execution environment based on an encryption chip. The method comprises: integrating an encryption chip on a terminal device; controlling the encryption chip by a terminal device manufacturer to generate an encryption chip secret key as a secret key composition factor; generating a file encryption key protection key, used for protecting the file encryption key used when the file is encrypted in TEE service, and preventing problems that in the TEE service process, a chip manufacturer can completely decrypt the ciphertext data into a plaintext when leaving backdoor in the key generation process or performing inverse operation on the encryption key, and the sensitive data has the risk of being stolen. The security of the file encryption key is improved, and the autonomy and controllability of the terminal device manufacturer in encryption service are also improved. The embodiment is an improvement on the basis of an original TEE file encryption technology. The controllability of file encrypted storage and key algorithm is more conveniently realized under the condition that the encryptionand decryption efficiency of the original technology is not changed, and the security risk of key leakage is avoided.

The invention relates to an intelligent power grid technology, in particular to an intelligent power grid data management system and method based on a main right block chain technology. The system comprises a data collection module, a registration and authentication center, a data index module, a data processing and consensus module, an intelligent contract module, a main right block chain network, and a power data application module. According to the present invention, not only the problem of electric power data leakage risk caused by a large amount of data in the smart power grid is solved, but also the mining value of the electric power data is improved, and the electric power data mining process is standardized. By writing the national law regulations into a block chain intelligent contract, and placing the diverse and complex application and management block chains of the power data under supervision of the law regulations, the advantages of power user identity information controllability, intelligent contract legality supervision, power information targeted opening and the like in the block chain are realized, and the storage and utilization efficiency of the electric power data is improved through the block chain structure of the electric power data application service type identifier.

The invention discloses a file security method in a limited area based on position information, which aims at safe communication in a certain area. A file security system in the limited area based on the position information is established at first, wherein the file security system is composed of user hosts, a safety management host and a global positioning system, the safety management host is equipped with a file privilege management program, and each user host is provided with a position information module and a file privilege service program. The security method comprises that the safety management host generates a private key for the user host; a sending part encrypts a message, and a position private key is generated according to a safety area limited by the message; the safety management host determines data validity of a position private key of a receiving part to verify whether the receiving part is in the safety area; and the receiving part decrypts the message in the limited area. The file security method controls the private area via double authentication means including user password and geographical position, and is suitable for secret places as secret conferences and secret rooms.

The invention discloses a point contact shape correcting method of a Niemain worm gear. The method includes the steps that S1, an original precise model is established; S2, coordinates of a central point of an exit region and the normal vector of the tooth surface of the point are acquired; S3, a tangent plane of the tooth surface of the worm gear is established by passing the central point of the exit region, and a coordinate system is established on the plane; S4, points on the tooth surface of the worm gear are projected on the tangent plane; S5, projection point coordinates are substituted into a shape correcting amount equation to obtain the shape correcting amount of projected points; S6, the points on the tooth surface of the worm gear deviate into gear teeth along the normal vectors of the tooth surfaces of the points; S7, the deviating points are fit into a smooth surface, namely a shape-corrected tooth surface in a high order mode; S8, the shape-corrected tooth surface and the original tooth surface are subjected to deviation comparison in three-dimensional software, if spots meet requirements, the operation is completed, or else, shape correcting amount equation coefficients in S5 are adjusted, and S5 to S8 are repeated. The method has the advantages that the sensitivity of the tooth surface of the Niemain worm gear to errors and tooth surface contact stress concentration are effectively improved, drive precision is improved, and the vibration and noise level of engagement is reduced.

The invention provides a preparation method of a crystal controllable drug balloon catheter, the prepared drug balloon catheter and application thereof. A low-pressure transverse ultrasonic spraying method is adopted to spray a drug coating on the surface of a balloon, and the crystal controllable drug balloon catheter is obtained. Controllable selection of drug coating crystal size can be achieved by adopting the low-pressure transverse ultrasonic spraying method, so that the drug coating on the surface of the balloon is more uniform, particles are more uniform, a drug solution can be flushed to the surface of the balloon through low-pressure transverse ultrasonic spraying, and the drug coating firmness is improved. The preparation method has a crystal controllable characteristic, the influence of environmental factors on the drug coating firmness and the crystalline state of an active drug contained in the drug coating can be also avoided, and the preparation method is simple and used for industrial production.

The invention relates to an electronic control variable-damping rotation hydraulic damper which comprises a motor, an outer shell, a blade, a valve element, a valve body, a shaft, a spring, a cover plate and the like. Due to the fact that a guide groove is formed in the middle shaft of the variable-damping rotation hydraulic damper, a guide rail is arranged on the shell, the blade automatically moves transversely in the radial direction along with the guide rail during rotation, the volume of driven liquid is changed, the liquid flows in a circulated manner through the valve element, and the function that the rotation angle of the damper is unlimited is achieved; and the valve element is driven by a step motor to rotate, so that the size of the drift diameter of a runner composed of the valve element and the valve body is variable, and the function of being adjustable in rotation damping is achieved.

The invention relates to the technical field of financial science and technology, and discloses a file operation method, a device, equipment, a system and a computer readable storage medium. The fileoperation method comprises the steps that when a file operation request is received, user information, a target file storage path and target operation are acquired according to the file operation request; the identity verification and operation authority verification is performed on the user based on the user information, the target file storage path and the target operation; when the identity verification and the operation authority verification are both passed, a target remote file service is determined according to the target file storage path and a preset rule; and a super user permissionis obtained through the target remote file service, a target operation method corresponding to the target operation is called based on the super user permission, and the target operation is executed on a target file corresponding to the target file storage path. According to the invention, the controllability of user permission management and the security of file system operation access can be improved.

The invention relates to a method for fast preparing a hollow porous silicon dioxide / silver nanoparticle composite. The method includes the steps that a glucose water solution and a sodium silicate solution are mixed and then placed in a high-pressure hydrothermal kettle for a sustained reaction to obtain a carbonaceous ball silicon dioxide shell composite reactant, the reactant is centrifugally dried and then calcined in air for 3-8 h, and carbon nuclei are removed to obtain hollow porous silicon dioxide nanoparticles; the obtained silicon dioxide particles are fully dispersed in a mixed solution of a cetyl trimethyl ammonium bromide (CTAB) water solution and hydrazine hydrate, a dilute silver nitrate solution is added drop by drop, the mixture is stirred magnetically for a sustained reaction, and the obtained product is centrifugally separated to obtain the hollow porous silicon dioxide / silver nanoparticle material. The simple two-step method including a one-step hydrothermal method and a one-step reduction method is used for preparing hollow porous silicon dioxide / silver nanoparticles, and the hollow porous silicon dioxide nanoparticles are prepared through the one-step hydrothermal method, and the particle size of the hollow porous silicon dioxide nanoparticles can be adjusted conveniently; silver is reduced through the one-step reduction method, the preparation technology is simple, the reaction is fast, and large-scale industrial production can be achieved.

The double-blowing two-seat two-row vertical pellet-roasting furnace includes stoving bed, blast guiding chamber, dust laying chamber, blast guiding pipe, combustor, roasting chamber, roasting blast distributing chamber, material laying unit, material distributing unit and pre-drying unit. It features the complex furnace form with burners on two sides of the roasting band, cooling jets on two sides of the cooling band, air exhaust ports on two sides of the end of the cooling band, dust laying chamber below the blast guiding chamber and the pellet pre-drying unit over the stoving bed. The present invention has improved heating, cooling and ventilating mechanisms of vertical furnace, and has the advantages of reinforced roasting, reinforced cooling, reinforced drying, controllable airflow motion, etc.

The invention provides a spherical Ti3Al / TiAl two-phase alloy and a preparation method thereof, relating to a two-phase alloy and a preparation method thereof. The invention aims to solve the problems of difficult control on TiAl alloy components, high oxygen content and impurity content and poor sintering performance. The spherical Ti3Al / TiAl two-phase alloy is composed of Ti and Al; and the mass ratio of Ti to Al is (65-68):(32-35). The preparation method of the spherical Ti3Al / TiAl two-phase alloy comprises the following steps: 1, weighing Ti powder and Al ingots, and impregnating at the impregnation temperature of 660-720 DEG C for 0.5-3 hours to obtain a Ti-Al-TiAl3 three-phase compound body; and 2, preserving the Ti-Al-TiAl3 three-phase compound body at the temperature of 1100-1400 DEG C and the pressure of 40-80 MPa for 0.5-2 hours to obtain the spherical Ti3Al / TiAl two-phase alloy. The density of the two-phase alloy is higher than 98%. The invention is applicable to the fieldsof aerospace engines and automobile industry.

The invention discloses a high-temperature-resistant wide-temperature-range high-damping polyurethane elastomer material and a preparation method thereof. The raw material formula of the material comprises the following components in parts by weight: 12-48 parts of a polyurethane prepolymer, 2-8 parts of a disulfide bond-containing micromolecular chain extender and 5-25 parts of a suspension chainprepolymer. The polyurethane prepolymer undergoes chain extension in virtue of the disulfide bond-containing micromolecular chain extender and then reacts with the suspension chain prepolymer to obtain the high-temperature-resistant wide-temperature-range high-damping polyurethane elastomer material. According to the invention, a few suspension chain structures can ensure certain mechanical properties while improving the damping performance of the polyurethane material, and the high temperature resistance of polysiloxane can improve the maximum long-term use temperature of polyurethane with the suspension chains; the effective damping temperature range (wherein tan delta is greater than or equal to 0.3) of the obtained damping material exceeds 170 DEG C; and the damping material can be used for a long time at 120 DEG C and has a good application effect.

The invention provides an air conditioner display interface control method, a system and a terminal. Wireless communication environment is formed between a control terminal and an air conditioner, a man-machine operation interface offered by the control terminal is used for setting the display interface adjusting parameter of the air conditioner, the control terminal is used for sending the set adjusting parameter to the air conditioner based on the formed wireless communication environment, then the air conditioner receives an interface control signal corresponding to the set display interface adjusting parameter and adjusts the display interface based on the set display interface adjusting parameter, so that the display interface of the air conditioner is controllable, the display effect and the display rule of the display interface of the air conditioner can be controlled by individual, the operation accuracy and convenience based on the display interface of the air conditioner are effectively improved and the customer complaints are reduced.

The invention discloses a goods transfer device for a vending machine platform. The goods transfer device comprises a goods loading mechanism and a driving mechanism. The goods loading mechanism comprises a tipping bucket seat (204) and a tipping bucket (200), wherein the tipping bucket seat is hinged to the tipping bucket, and the tipping bucket is mounted on the tipping bucket seat. The drivingmechanism is used for driving the tipping bucket seat to transversely move, the tipping bucket is inclined after the tipping bucket seat moves to a set position, and goods stored in the tipping bucketcan be poured out. The goods transfer device for the vending machine platform is easy to implement, and the goods can be transferred and poured.

The invention discloses a data sharing method, which comprises the following steps executed at each node: marking one of a first queue and a second queue as a current queue by using a preset mark, sothat the other queue is used as a non-current queue; receiving to-be-shared data of each micro-service component by utilizing the current queue; screening the data in the current queue according to apreset rule, and emptying the current queue after synchronizing the screened data to a non-current queue; transferring the preset mark of the current queue to a non-current queue, so as to enable thecurrent queue to be converted into the non-current queue, enable the non-current queue to be converted into the current queue, and returning to receive the to-be-shared data of each micro-service component by utilizing the current queue. The invention further discloses computer equipment and a readable storage medium. According to the scheme provided by the invention, data sharing is realized through the first queue and the second queue, so that data controllability can be realized, namely partial data can be deleted according to actual requirements, and partial data can be reserved.

The invention relates to a preparation method of a lithium-sulfur battery based on a large-area thick film controllable texture photonic crystal, which is characterized in that a vertical sedimentation self-assembly method is used; along with the volatilization of a solvent, monodisperse microspheres are arranged in macropores of a base material to form a photonic crystal structure, the photonic crystal is used as a template, ordered microporous carbon is synthesized in gaps of the template, and the photonic crystal template is removed to obtain a carbon photonic crystal with a three-dimensional ordered hierarchical porous structure, so that the large-area thick film controllable texture photonic crystal is formed. The texture photonic crystal is compounded with elemental sulfur to obtaina sulfur positive electrode, and lithium metal is taken as a counter electrode so as to assemble the lithium-sulfur battery. By changing the thickness of the base material and the concentration of a turbid liquid, the thick film controllability of the electrode thickness ranging from 10 micrometers to 650 micrometers is achieved, and meanwhile, large-area preparation with the electrode area ranging from 0.1cm<2> to 400cm <2> is achieved by changing the area of the base material. In addition, high load of sulfur from 1-15mg.cm<-2> is achieved by adjusting the concentration of an organic solution of sulfur, so that high surface capacity density and surface energy density of the lithium-sulfur battery are realized.

The invention provides an account set maintenance and management system, which comprises eight modules: a database, a user register module, a login module, a service management module, a contract management module, an account keeping module, a statistics module, a synchronization module and an automatic reminding module, wherein the database, the login module, the contract management module, the account keeping module, the statistics module and the automatic reminding module realize synchronous data docking through the synchronization module; and the automatic reminding module can regularly remind a user to input required information according to reminding information and reminding date options input by the user in a setting interface. The system can monitor company and account informationin real time, can clearly display customers who do not pay the payment on time to carry out corresponding measures to recover the payment, and meanwhile, greatly increases data timeliness, accuracy and feasibility of finance management; and through reasonable configuration of the modules, the system can reflect information of customers with insufficient funds in time, thereby improving fund monitoring and operation capability.

The invention belongs to the field of rocket engines, and particularly relates to an interlayer ablation carbonization controllable experimental device for a double-pulse solid rocket engine. The interlayer ablation carbonization controllable experimental device for the double-pulse solid rocket engine comprises a three-way combustion chamber cavity, an end combustion charging assembly, a spray pipe assembly and an interlayer ablation fixing assembly; the spray pipe assembly and the interlayer ablation fixing assembly are respectively in threaded connection with two opposite through holes, andthe end combustion charging assembly is in threaded connection with the other through hole; after a grain in the end combustion charging assembly is ignited, fuel gas passes through the combustion chamber cavity and is discharged through the spray pipe assembly, and meanwhile, the fuel gas in the combustion chamber cavity makes direct contact with an interlayer ablation test piece fixed on the interlayer ablation fixing assembly. The interlayer ablation carbonization controllable experimental device for the double-pulse solid rocket engine provided by the invention can simulate the working environment of the real double-pulse solid rocket engine, the type, the structure size and the working pressure of a propellant in the end combustion charging assembly can be adjusted, and the controllability of single-side ablation of an interlayer is realized.

The invention relates to an information security protection system for a DCS system, and the system comprises an industrial security isolation gatekeeper which is disposed at the network boundary of a DCS network and an SIS system, and is used for isolating the DCS system from the SIS system, and protecting the security of the network boundary of the DCS system; an industrial network auditing system which is deployed in a main switch bypass of the DCS system and is used for network full-flow auditing, alarming and analyzing; an industrial log auditing system which is deployed in the DCS and is used for carrying out log data acquisition, classification and analysis on the safety equipment, the network equipment, the host system and the database; and an industrial intrusion detection system which is deployed at a bypass of the SIS three-layer core switch and is used for monitoring industrial network transmission data in real time and performing intrusion detection and alarm on network data traffic. According to the invention, safe and stable operation of the DCS system information network can be ensured.

The invention relates to an electronic control variable-damping rotation hydraulic damper which comprises a motor, an outer shell, a blade, a valve element, a valve body, a shaft, a spring, a cover plate and the like. Due to the fact that a guide groove is formed in the middle shaft of the variable-damping rotation hydraulic damper, a guide rail is arranged on the shell, the blade automatically moves transversely in the radial direction along with the guide rail during rotation, the volume of driven liquid is changed, the liquid flows in a circulated manner through the valve element, and the function that the rotation angle of the damper is unlimited is achieved; and the valve element is driven by a step motor to rotate, so that the size of the drift diameter of a runner composed of the valve element and the valve body is variable, and the function of being adjustable in rotation damping is achieved.

The invention discloses a miniaturized substrate integrated waveguide filter comprising a substrate and a microstrip line structure connected to the substrate as an input and an output separately, wherein the lower surface of the substrate is clad with copper; a slotted structure is etched on the upper surface of the substrate and is rotationally symmetric about the center of the substrate; and two open resonators are disposed on the upper surface of the substrate. In addition, the present invention also discloses a high-order filter based on the miniaturized substrate integrated waveguide filter. A high-order resonator is arranged between the two open resonators in order to improve the rectangularity of the filter and improve the frequency selection performance of the filter. The S-shapedslotted structure is etched on the surface of the substrate so as to achieve two equivalent short-circuited quarter-wave resonators to form a second-order band-pass filter, thereby miniaturizing thefilter.

The invention belongs to the technical field of big data analysis, and discloses an information pushing method and device based on big data analysis, equipment and a storage medium. The method comprises the following steps: acquiring network data published by a to-be-monitored we-media account in different time periods; analyzing the network data in each time period by utilizing a pre-constructedbig data analysis model to obtain a change rate of a hotspot corresponding to the network data; predicting whether the hotspot has a push value or not according to the change rate and a preset information value judgment standard; and if the predicted hotspot has the push value, pushing the network data to the user, so that the user formulates a service scheme fitting the hotspot according to the network data. Through the mode, the technical problem that valuable information cannot be quickly and accurately recognized from numerous network data and cannot be pushed to a user in the prior art issolved.

The invention is applicable to the field of machine learning and provides a confidence regression algorithm based on KNN (K-Nearest-Neighbor). The confidence regression algorithm comprises the following steps: determining a sample set, wherein the sample set comprises a known regression sample set and an unknown regression sample set; selecting an unknown sample from the unknown regression sample set and calculating an Euclidean distance between the unknown sample and each sample in the known regression sample set; inquiring K samples with the Euclidean distances which are the closest to the unknown sample from the known regression sample set; calculating an average value of regression values of the K samples; predicating a regression value of the unknown sample by a regression module; calculating a difference value T between the regression value and the average value; and dividing an acceptance domain and a rejection domain according to the difference value T. The confidence regression algorithm based on the KNN has the advantage that the regression value is accurate.

The invention discloses silicon carbide single crystal growth equipment with a function of adjusting the ratio of carbon to silicon in a growth atmosphere, which comprises a quartz tube, an induction coil and a graphite crucible, the graphite crucible comprises a silicon carbide powder heating area, a growth chamber and a seed crystal support, a second cover plate and a third cover plate are further arranged between the silicon carbide powder heating area and the growth chamber, and a vertical air pipe penetrating through silicon carbide powder is arranged at the bottom of the silicon carbide powder heating area. According to the technical scheme, the structure that the bottom structure of the graphite crucible is matched with a multiple cover plates is adopted, multi-space separation of the silicon carbide powder heating area is achieved, the output path of gas components after sublimation of the silicon carbide powder is changed, sublimation gas passes through the silicon carbide powder multiple times and forms a continuous large cycle, the silicon carbide powder is repeatedly heated for multiple times, the sublimation speed of the silicon-rich component gas and the sublimation speed of the carbon-rich component gas are coordinated, and then the high-quality silicon carbide single crystal is obtained.

The invention discloses a method for preparing texture on the surfaces of silicon wafers. The method comprises the following steps: the surfaces of the silicon wafers are cleaned and purified, each two cleaned and purified silicon wafers are overlapped and placed in a vapor deposition reacting furnace; when the temperature of the vapor deposition reacting furnace is controlled to 1050 to 1200 DEG C and the vacuum degree is controlled in the range of 1*10<-2>Pa to 1*10<-4>Pa, trichlorosilane and hydrogen are mixed according to the required reaction molar ratio of the chemical equation, the mixture is introduced in the vapor deposition reacting furnace to ensure that crystalline silicon deposits on the exposed surfaces of each two overlapped silicon wafers and silicon grain texture surfaces are formed; and nitrogen is introduced after the deposition, the temperature of the vapor deposition reacting furnace is reduced to the room temperature, the pressure of the furnace is increased to the atmospheric pressure, and the silicon wafers with the deposited silicon grain texture surfaces are taken out. The thickness of the texture layers of the silicon grain texture surfaces which are prepared on the surfaces of the silicon wafers by the texture-preparing method of the invention is 5mu m-8mu m, and the average reflectivity of the surfaces of the silicon wafers to the light with the wavelength of 300nm-1100nm is 7.5%-8.5%. The silicon grain texture surface layers can be controlled, the reflectivity of the silicon grain texture surface is reduced, the production process is simple, and the speed of the batch production is fast.