472results about How to "Clear steps" patented technology

The invention relates to a method for generating three-dimensional imaging original echoed signals of chromatography synthetic aperture radars, which comprises the following steps: taking a three-dimensional image containing backward plural scattering coefficients of imaging area targets in a rectangular coordinate system OXYZ as the input, carrying out three dimensional fourier transform on the three-dimensional image and converting an image signal to a rectangular coordinate system wave-number domain; converting signals in Kx, Ky and Kz domains to be signals in Kw, Ku and Kv domains according to the method of converting the rectangular coordinate system to a spherical coordinate system; introducing imaging geometrical relationships among same imaging area of chromatography synthetic aperture radars by multiplying three dimensional filter function H2 (Kw, Ku and Kv); introducing a transmission signal form by the multiplication of a two-dimensional inverse Fourier transform function and a reference phase function; and at last, by W direction process and other operations, obtaining the three-dimensional imaging original echoed signals of chromatography synthetic aperture radars, which contains a carrier frequency. The method can be used for generating three-dimensional imaging original echoed signals of side-looking, downward-looking, forward-looking, backward-looking and downward side-looking chromatography synthetic aperture radars, and has high echo generating efficiency and easy realization of modularization.

The invention provides a static voltage stability margin analyzing and system fault ordering method of a power system. The static voltage stability margin analyzing and system fault ordering method includes the following steps that the Newton iteration method based on the optimal multiplier is used for determining a static voltage collapse point; according to the characteristic of iteration convergence, the type of the voltage collapse point is judged; according to the requirement for stability margin, system fault danger conditions are checked and ordering of stability faults is performed; the faults are parameterized and the iteration method is used for giving out the order of seriousness degrees of instability faults. According to the static voltage stability margin analyzing and system fault ordering method of the power system, voltage stability margins of the power system can be rapidly given online, real-time effective monitoring is carried out on the voltage stability and the comprehensive order of the stability faults and the instability faults can be used for guiding a power generator to adjust online and switching reactive power compensation devices when the system encounters faults, can also guide sub-circuit parameter adjusting, line increasing and decreasing, configuration of an FACTS device and the like off line and have great significance in operation and planning of the power system.

The invention provides a subject characteristic value algorithm and a subject characteristic value algorithm-based project evaluation expert recommendation algorithm. The subject characteristic value algorithm-based project evaluation expert recommendation algorithm comprises the following steps: (1) carrying out text similarity calculation: 1) carrying out word segmentation on text information of the project study content and evaluation expert research direction, 2) carrying out establishment of a text characteristic vector model of the project study content and evaluation expert research direction, and 3) carrying out similarity calculation on the text characteristic vector of the project study content and evaluation expert research direction; (2) carrying out the subject characteristic value algorithm; (3) carrying out calculation on the project evaluation expert recommendation value, wherein the calculation formula is as follows: ProSim(V, U)=w(c) x exp[sim(V,U)]; (4) sequencing the project evaluation expert recommendation values obtained by calculation in the step (3). The subject characteristic value algorithm and the subject characteristic value algorithm-based project evaluation expert recommendation algorithm disclosed by the invention has the advantages that under the condition of no artificial interference, a processing program which applies the project evaluation expert recommendation algorithm can automatically calculate scientific research projects and recommendation values of different evaluation experts, and user time is saved.

The invention discloses a rice screening method. According to the method, thirteen processes, namely blowing, screening and washing, blasting and drying, stone removal, magnetic separation, decldding, husked rice separation, thickness classification, rice milling, rice classification, colour selection, grade separation and finished product package, are adopted for finishing ice processing. According to the rice screening method, all process of a traditional process are optimized, all the steps are simplified, and the quality is ensured; especially a screening and washing process is added, so that dust and other water-soluble impurities can be removed by virtue of screening and washing, so that the rice is relatively clean, the prepared rice and rice chaff are relatively high in cleanliness and the rice product is high in quality and clean; a traditional polishing process is omitted, and a membrane which is rich in microelements at the outer surface of rice is reserved, so that losses of rice nutritional ingredients are prevented and the rice is relatively nutritional; the rice screening method is clear and reasonable in step, high in whole rice rate and high in production efficiency, and the prepared rice is high in nutritional ingredients, good in taste, high in quality and clean.

The invention discloses a fracturing method for deep shale gas through a V-shaped pressure curve. The fracturing method comprises the steps of (1) key reservoir parameter evaluation, (2) optimizationof fracture parameters and fracturing construction parameters, (3) perforation position determination and perforation operation, (4) acid pretreatment, (5) variable-displacement and low-viscosity slick water joint forming construction, (6) powder pottery construction for adding different sand liquid ratios into low-viscosity slick water, (7) medium-particle-size proppant construction for adding different sand liquid ratios into medium-viscosity slick water, (8) high-viscosity gel and large-particle-size carrying proppant construction, and (9) displacing operation. According to the fracturing method, complexity of fracturing fractures of the deep shale gas is improved, the filling ratios of systems with different scales of fractures such as near wells, far wells, main fractures and micro-fractures are increased, the effective stimulation volume of the deep shale gas is increased, and the yield increasing and stabilizing effects after pressure are improved.

The invention provides a cutter matching method for a machining process. A selective range of cutters to be matched is gradually decreased according to different characteristics of parts to be machined to obtain multiple cutters to be selected satisfying part processing requirements; and then, a final cutter is selected through calculating a carbon emission. The matching method is clear in steps and definite in levels, can reduce the cutter matching complexity, and can improve the reasoning efficiency and the accuracy of cutter matching. As the carbon emission in the machining process is introduced into a cutter matching scheme evaluation as a final selecting standard of the cutters to be matched, on the one hand, the finally matched cutter scheme is closer to actual production requirements to guarantee the matching result practicability, and on the other hand, the control of energy consumption of a workshop production system and the control of the carbon emission in the machining process are realized to a certain extent to improve the green degree of the whole system and to provide the reference for the realization of efficient cutter selection, energy conservation and emission reduction in the machining process.

The invention provides an offline automatic brick stacking assembly line. The offline automatic brick stacking assembly line comprises a brick arranging device, a brick transferring device and a brick stacking device, wherein brick layers can be reduced by at least one row or one line relative to the upper layer or the lower layer through the brick arranging device, the corresponding brick layer can be rotated by a predetermined angle relative to the upper layer or the lower layer through the brick transferring device, so that a formed brick stack is more stable, the brick layers in the reduced row or line can be pulled to be separated while the brick layers in the non-reduced rows or lines are stacked, so that a gap is formed between every two adjacent rows or lines, then stacking is conducted, after the formed brick stack is packaged, a transporter can be inserted into the gaps conveniently for grabbing, and when two gaps exist, the two insertion angles of a forklift can be inserted for transportation. In this way, the offline automatic brick stacking assembly line has the advantages that brick stacking quality is high, efficiency is high, the formed brick stack can be transported by the transporter such as the forklift conveniently, the degree of mechanization and the degree of automation are high, the assembly line can be adapted to various types of bricks and various brick forming machines, and practicability is high. The invention further provides a brick stacking method. All the functions can be achieved effectively by the adoption of the brick stacking method.

The invention discloses an order-driven discrete manufacturing process energy consumption optimization method. A precondition of realizing energy consumption optimization of a discrete manufacturing process is to acquire operation energy consumption information of a processing process. Therefore, in the invention, firstly, according to machine tool performance, a processing material, a processing technology parameter and prediction of NC code realization operation energy consumption, data support is provided for resource configuration which is performed on low energy consumption production of a system layer; and then, an improved multi-object optimization intelligence algorithm is designed and used to carry out production resource optimization configuration of the discrete manufacturing process so that optimization objects of finishing time, processing cost, processing energy consumption and the like are guaranteed to be coordinated and optimized. In the invention, a new idea is provided for the energy consumption optimization of the order-driven discrete manufacturing process and a reference is provided for realizing low energy consumption production and green manufacturing.

The invention discloses a volume fracturing method for deep complex shale gas. The method includes the following steps: (1) performing evaluation on key reservoir parameters; (2) preparing acidic slick-water and ground crosslinking acid; (3) performing perforation position determining and perforation operation; (4) performing optimization on fracture parameters and main parameters of a fracturingtechnology; (5) performing acid pretreatment operation; (6) performing small test fracturing; (7) performing fracture generation construction by using a high viscosity ground crosslinking acid prepadfluid; (8) performing viscous fingering injection construction of the low viscosity acid slick-water; and (9) performing acidic slick-water sand-carrying construction. Therefore, the complexity of volume fracturing fractures of deep complex shale gas can be enhanced, the sand blocking risks of construction can be reduced, the filling rates of near well and far well fracture systems can be increased, the effective reforming volume of the deep complex shale gas can be enhanced, and effects of increasing and stabilizing production after fracturing can be improved.

The invention provides an H-bridge cascade type STATCOM control system based on model prediction, and belongs to H-bridge cascade type STATCOM control systems. Firstly, current converter output voltage, power grid voltage and current converter compensation current are sampled, the sampled current converter output voltage, power grid voltage and current converter compensation current and reference current obtained in a detection link are respectively transformed to an alpha-beta coordinate system, and a prediction model of current converter compensation current is acquired after discretization; secondly, reference current is predicted, and a value function for current tracking control is established in combination with compensation current obtained in the step one; thirdly, an inverter output voltage vector and peripheral six vectors of the current sampling period are confirmed to act as an optimizing set for the output voltage vector of the next sampling period; and fourthly, compensation current tracking control value function optimizing is performed according to the step two and the step three so that the output voltage vector of the next sampling period is confirmed and the switching state of the next period is obtained, and vector screening is performed in combination with DC side capacitor voltage control when redundant vectors are generated. Realization is easy, the hardware requirements are reduced and system response speed is increased.

The invention belongs to the technological field of the Chinese medicine, particularly relating to an extraction and separation processes of the active ingredients with the active function of treating the chronic glomerulonephritis. The mullein indican is the active compound researched and developed for many years in our research institute; the mullein indican is extracted, separated and refined from the digitalis leaf and is an active compound with the function of treating the chronic glomerulonephritis. The invention is the research result of many years held and developed by the Chinese Medicine Research Department of the Chinese Medicine Research Institute of China and is supported by the special fund of the Central Institute of the National Science and Technology Department; now the compound has been approved by the State Food and Drug Administration Bureau as the novel drug and the mechanism research of the treatment of the chronic nephritis has been completed; the pre-clinical research work includes the main pharmacodynamic experiment, the production technology experiment (including the industrialized extraction and separation processes), the quality control standard, the experiment of the affecting factors of the quality, the experiment of the long-term stability, the acute toxicity of the rat, the experiment of the long-term toxicity, the teratogenic and mutagenic experiment, the general pharmacological experiment, the pharmacokinetics experiment, and so on. The digitalis leaf is mainly produced in the Huaiqing area of the Henan province, and is also grown wild and cultivated in the Shaanxi, Hebei and other places of China.

The invention discloses a low temperature flue gas denitration catalyst and a preparation method thereof. The catalyst is represented by a general formula of MnOX-CeO2 / TiO2-SiO2, wherein TiO2-SiO2 is a composite oxide carrier, a molar ratio of TiO2 to SiO2 is 1:0.5-1.5, MnOX and CeO2 are active components of the catalyst, the load capacity of MnOX is 0.5-2wt%, and the load capacity of CeO2 is 5-15wt%. The catalyst can realize ammonia selective catalytic reduction of nitrogen oxides into harmless nitrogen and water at 100-180DEG C, has a highest denitration efficiency reaching 96%, and has an excellent denitration effect; and the preparation method has the advantages of clear steps, simple operation and easy enforcement.

The invention discloses a machining method for a three-dimensional flow impeller. An original whole forging of a wheel cover is changed into a panel, the wheel cover is formed through a die and spliced with an inlet ring in a welding manner, then, the wheel cover and blades manufactured in advance are spliced and formed, finally, a wheel disc and the wheel cover are welded and formed, and finish turning is carried out after thermal treatment. An impeller and the blades are independently manufactured and spliced together through spliced welding. Compared with the traditional technology, by means of the whole forging forming, the integral strength cannot be changed, the consumption of raw materials is greatly reduced through the new technology, the machining difficulty is lowered, and the machining efficiency is improved.

The invention discloses a nondestructive measuring method for the leaf area of a broad leaved plant, and aims to solve the problem that a measured leaf is destroyed in the prior art. The nondestructive measuring method comprises the following steps: 1, measuring an area S1 of a white board through a ruler, wherein S1 is equal to 10cm*10cm, namely 100cm<2>; 2, photographing the white board and the measured leaf; 3, cropping photos; 4, respectively weighing the picture weight of the white board G1 and the picture weight of the measured leaf G2; 5, calculating the real area S2 of the measured leaf, wherein S2 is equal to S1*G2 / G1; 6, weighing the picture weight of the measured leaf when a part of the measured leaf is illuminated; 7, calculating the relative total area S3 of the measured leaf when the part of the measured leaf is illuminated; and 8, calculating the relative area S4 of the illuminated part of the leaf, wherein the relative area S4 of the illuminated part of the leaf is obtained through a formula (S4 / S3 is equal to G4 / G3); and S4 is equal to G4 / G3*S3.

The invention provides a bearing integrated maintaining device and method. Bearing efficient washing, drying and oil injection functions are achieved in the same device. The bearing integrated maintaining device comprises a spraying washing component, a combination frequency ultrasonic cleaning component, a cold air drying component, an oil injection component, an air path component and a control system. The combination frequency ultrasonic cleaning component comprises a combination frequency ultrasonic generator, an ultrasonic transducer array and an ultrasonic cleaning groove. A plurality of spraying head sets and cold air drying spraying heads sets are arranged in the spraying washing component. The directions of nozzles of the spraying heads can be adjustable. According to the bearing integrated maintaining method, spraying washing, combination frequency ultrasonic washing, bearing drying and bearing oil injecting are completed in the same device. The combination frequency ultrasonic washing frequency range is 15kHz-20kHz and 25kHz-30kHz. During spraying washing, in single-time washing in the same spraying component, high-pressure straight washing and high-pressure oblique washing on a bearing in the upper direction and the lower direction are completed.

The invention discloses an aero-engine main force bearing component overall static strength assessment test system and an aero-engine main force bearing component overall static strength assessment test method. The aero-engine main force bearing component overall static strength assessment test system comprises a plurality of loading assemblies and a measuring mechanism, wherein adapting sections at left and right ends of a test assembly are connected with test frameworks through the plurality of loading assemblies, upper and lower ends of the test assembly are fixed on the test frameworks, the lower part of the test assembly is connected with the lower test framework through the fourth loading assembly, and the measuring mechanism is arranged on the right test framework and is connected with the test assembly. The test method provided by the invention has clear and feasible test steps and detailed loading process, can truly simulate working states of an aero-engine main force bearing component, applies complex load on the integral aero-engine main force bearing component synchronously on a test device, and is suitable for carrying out static strength assessment tests on various types of aero-engine main force bearing components integrally.

The invention provides a recruitment system, which comprises a job publication module, a job matching module, a job notification module and a job application module; the job publication module receives a job information request from an enterprise, and acquires and sends the job information of the enterprise to the job matching module; the job matching module intelligently matches the job information sent by the job publication module with the data in a job seeker resource library on line to locate job seekers meeting the requirements of the job, and sends the information of the job seekers meeting the requirements of the job to the job notification module; the job notification module receives the job matching result and notifies the job seekers meeting the requirements of the job of the job information by various ways, so that the job seekers can apply for the job, and the job notification module sends the applications of the job seekers to the job application module; the job application module receives the applications of the matched job seekers, and notifies the enterprise of the applications by various ways, and thereby the two parties can rapidly reach employment relationship. The structure of the recruitment system provided by the invention is clear, the steps are clear, and enterprises can conveniently utilize the system to recruit talent on line.

The invention provides a method for evaluating tangential distortion indexes of a lens of a camera. The method comprises the following steps: acquiring an image filmed by the lens of the camera, wherein a template exists in a filmed scene; extracting image points on the template in the image; determining that the points on the template correspond with points of the image; calculating evaluation indexes by a formula by using coordinates of the points on the template and coordinates of corresponding points on the image; and evaluating the lens according to index values. The method can comprehensively evaluate the tangential distortion of the lens of the camera, and can provide guidance standards for calibration of an omnidirectional camera. The method is independent of the radial distortion,has the characteristics of convenience, practicality, high precision of evaluation standards, good robustness and the like, and ensures that the quality control detecting method for producing wide-angle lenses tends towards practicality and convenience.

The invention discloses an asphalt pavement load temperature coupling testing device and testing method thereof. The method comprises the following steps: uniformly heating a test piece to be tested by adopting a heating plate, applying pressure to the test piece to be tested through a hydraulic cylinder, and controlling an air inlet fan, an exhaust fan and the heating plate through a computer, so that the temperature is in sine curve change during test; and recording the stress change of each point inside the test piece to be tested under load and temperature changes though a stress sensor embedded inside the test piece to be tested. The experiment is carried out through step-related experimental conditions, the experimental result is compared to determine a coupling effect of the asphalt pavement load temperature, the experimental device is reasonable in structure, high in testing accuracy and high in testing stability, and the test method is clear in steps, simple in operation and high in degree of automation.

A space vector modulation method of a four-leg converter based on a classification algorithm and an apparatus thereof belong to a four-leg converter vector modulation method. The method comprises the following steps: 1. Using three phase reference voltages vref1, vref2 and vref3 to calculate six intermediate variables nI, acquiring a maximum intermediate variable nI and a secondly maximum intermediate variable nI through a comparison network so as to determine a triangular prism where a reference voltage space vector Vref is located; 2. Carrying out clark transformation on an input signal and determining a located tetrahedron through a relation between the reference voltage space vector Vref and five planes in the triangular prism; 3. Defining n0 and calculating action time t1, t2, t3 of three adjacent basic voltage space vectors V1,V2 and V3 through linear combination with the maximum intermediate variable nI and a secondly maximum intermediate variable nI in the step 1; 4. According to above results, switching a switching device of the converter so that an output voltage of the four-leg converter is equivalent with a reference voltage. An algorithm realization process is simplified and comprises: calculating the intermediate variables; determining a maximum value and a secondly maximum value of the intermediate variables; carrying out the linear combination on the intermediate variables. The steps are intelligible. The realization is simple. Computation of the algorithm is small and real-time performance is strong.

The invention discloses a non-downsampling shear wave medical CT image denoising method. The method comprises the following steps: 1) establishing a medical CT scanning image model; 2) performing NSSTmulti-scale decomposition and multi-direction decomposition on the CT image to obtain a low-frequency sub-band and a plurality of high-frequency sub-bands; 3) decomposing the original image into a smooth geometric part and a noise-containing texture part by using rapid geometric texture decomposition, and fusing a geometric part component and a low-frequency sub-band; 4) performing noise reduction processing on the fused new low-frequency component by adopting a trilateral filtering method to obtain a new low-frequency sub-band; 5) processing the high-frequency sub-band coefficient after theshear wave transformation by adopting a self-adaptive threshold shrinkage method; according to the medical CT image de-noising method based on the NSST, experimental analysis is compared with a traditional de-noising field algorithm, the method is effectively applied to the field of medical CT de-noising, and analysis and diagnosis of doctors can be better facilitated.

The invention discloses a snakelike robot kinetic analysis method based on a spinor theory and a Kane method. The method combines with the spinor theory and the Kane method, and defines an active force spinor, an inertia force spinor, a partial velocity spinor, a generalized active force, and a generalized inertia force and other parameters, and according to experimental observation of the snakelike robot, related parameters corresponding to the snakelike robot are solved, and a kinetic model is established, so as to give out a kinetic analysis method of the snakelike robot. Specific steps comprise: combined with the spinor theory, defining a Kane equation, measuring and approximating each joint quality, length, and undersurface radius of the snakelike robot, and according to experimentalobservation and theoretical equations, deriving each quantity required by the Kane equation, and establishing a Kane kinetic equation. The method combines the spinor theory and the Kane method, and effectively improves calculation speed and calculation efficiency, and the kinetic model of the snakelike robot is improved, and the model is concise and beautiful.

Provided is a spacecraft autonomous rendezvous control system ground simulation test method, belonging to the spaceflight control ground simulation field. The method comprises the steps of: 1) determining a basic dimension corresponding physical quantity similarity ratio coefficient according to the relation between verification object task parameters and ground test system parameters; 2) according to the similarity ratio coefficient, respectively establishing kinetic equations of a target simulator and tracking simulator motion in computer simulation; 3) connecting the simulator kinetic equation, the simulator (including control), a motion measuring sensor and an autonomous rendezvous controller to form a ground test closed loop system; and 4) controlling the simulator to track the motion track solved by a kinetic equation in the computer, and reproducing a spacecraft autonomous rendezvous motion process in a ground test room. The spacecraft autonomous rendezvous control system ground simulation test method lays a theoretical foundation for an autonomous rendezvous control semi-physical simulation test, and can simultaneously reflect simulator and tracking spacecraft absolute and relative motion characteristics on the ground, and verify an omnidirectional autonomous rendezvous control task.

The invention relates to a method for assessing network capacity applicability of a high-speed rail based on passenger flow dynamic allocation. The method comprises the following steps of: firstly, acquiring time varying requirement, section transportation capability and section service time scope of the high-speed rail; discretizing the travel time, section transportation capability, check purchasing time, section service time scope and network; performing passenger flow dynamic allocation by adopting an epsilon-saturated passenger flow loading method; assessing the network capacity applicability of the high-speed rail on the basis of a passenger flow allocation result; if O-D pairs all have no un-loadable requirement, indicating strong network capacity applicability of the high-speed rail; if O-D pairs have un-loadable requirement, indicating weak network capacity applicability of the high-speed rail; and for the O-D pairs having un-loadable requirement, increasing the network carrying capacity of the high-speed rail in the corresponding section by increasing the number of the train pairs and increasing the running frequency. The assessing method provided by the invention has the advantages of simple steps, strong practicability, standard implementation, reasonable and scientific assessing result and easy realization through software procedures.

The invention relates to a rice processing method. The method comprises the following steps of (1) clearing and removing impurities of paddy rice: feeding paddy rice raw materials into an iron screen impurity removing device to remove and clear the impurities; (2) magnetic separating and hulling rice: removing paddy rice shells through a hulling machine after metal substances mixed in the paddy rice are removed in a magnetic separation manner; (3) separating husked rice: separating the husked rice through a husked rice separating machine, and selecting the coarse rice; (4) grading the coarse rice: screening and grading the coarse rice through a grading machine; (5) rolling and polishing rice for multiple times; (6) cooling the rice: feeding the rice into a cooling room to be naturally cooled in the air, and ultraviolet sterilizing the rice in the cooling process; (7) whitening, polishing and color sorting the rice; (8) mixing the rice; (9) sterilizing; (10) packaging. The method has the beneficial effects that the steps are clear and reasonable, the rice taste is good, and the production efficiency can be improved.

The invention discloses a marine tensioned anode system and an installation method thereof. The system comprises a tensioning platform, combined cable tensioners, combined cables integrated with auxiliary anodes and reference electrodes, and gravity type foundations; the combined cable tensioners are mounted on the tensioning platform, the tensioners provide tensioning force for the upper ends ofthe combined cables, the lower ends of the combined cables are sunken to a seabed along with the gravity type foundations, moreover, the gravity type foundations provide anchorage points for the lowerends, and the combined cables integrated with the auxiliary anodes and the reference electrodes are a main part of the system. The system is simple in structure and is relatively convenient to install and transport. Meanwhile, the invention also discloses the installation method of the system. The method can be used for safely and reliably installing the marine tensioned anode system on a marineplatform. The installation method mainly includes: (1) hoisting of the combined cables and the gravity type foundations onto the installation platform; (2) submarine assembly of the gravity type foundations; (3) installation of the combined cables; (4) tension adjustment and locking fixation of the combined cables.

The invention discloses a method for testing thickness of a coating film. The method comprises the following steps of: drawing one or more strokes on a substrate by using a marking pen or an oil ink pen, and placing in a film coating chamber to coat a film, wherein the components of the marking pen or the oil ink pen are oily, so during sputtering, other substances are hardly adhered to the substrate and generated; and after the film is coated, soaking the substrate and a sample in a dissolving solution, reacting the ink marks drew with the marking pen or the oil ink pen to expose one or more passes of clear steps, and measuring on a step tester. The accuracy and easy manipulation of thickness testing in the film coating process can be improved. In the method, a mask or chemical corrosion liquid is not used, so that cost and time can be saved; the marking pen or the oil ink pen, ethanol and acetone, and the like are long-prepared products which are easy and convenient to take and use and operate; and the steps are clear.

The invention relates to a forestation method for fighting drought and relates to the technical field of large-area tree planting. The method is characterized by including planting trees according to the environment, preparing soil in advance, foresting with container seedling, foresting through mulching, foresting through cutting trunks, soaking roots before planting, and tending managing. The method is clear and simple in step, easy in operation, quite convenient, reasonable, simple to implement, and good in implementation effect.

The invention relates to a carbon-serial conductive coating with ultralow content of carbon tubes. The coating comprises a basic coating and a conductive additive which is doped in the basic coating, wherein the conductive additive is a carbon nanotube array which is uniformly distributed in the basic coating; the mass percent concentration of the carbon nanotubes in the conductive coating is 0.1-0.5wt%; the surface resistance of a film formed by air-spraying the conductive coating is less than or equal to 10<9>ohm. The preparation method comprises the following steps: firstly, adding the carbon nanotube array into the basic coating for primary dispersion to obtain an intermediate mixed coating; then adding the intermediate mixed coating into the basic coating for secondary dispersion so as to obtain the conductive coating. The design provided by the invention can be applied to electrostatic spraying with relatively low content of carbon tube and relatively strong decorative performance of pigments, the carbon nanotube array is uniformly dispersed in the basic coating. The coating is simple in preparation method and relatively low in production cost.

The invention provides an oil and gas reservoir fracturing sand adding method, which comprises a fracturing crack forming stage and a sand adding stage. A multi-scale complex crack system is formed inthe fracturing crack forming stage, fracturing fluid with different viscosities and propping agents with different particle sizes are injected in the sand adding stage to adapt to the multi-scale crack system, and the crack system is filled and supported from far to near. According to the method provided by the invention, by optimizing and adjusting the construction parameters and adjusting and controlling the accumulation height of the proppant in the fracture, the effective support of the proppant in the fracture height direction is improved, the filling degree of a multi-scale complex fracture system is improved, the volume fracturing complex fracture sand adding technology is perfected and improved, and finally, the effects of increasing the yield after pressing and stabilizing the yield are improved.