74results about How to "Regulatory" patented technology

The present invention discloses a system and a method for logistics financing management based on a block chain technology, and relates to the technical field of logistics financing management. The system comprises a block chain ground floor platform which is in information interaction with a credit reference system, a supervision system, a service platform and an Oracle prediction machine througha data transmission and storage module; the credit reference system is connected with a bank credit reference system, an ant credit reference system and an individual credit reporting system; and theservice platform performs data transmission with the terminal device through the data transmission module. The system and the method for logistics financing management based on the block chain technology utilize the effects of the block chain ground layer platform, the credit reference system, the supervision system and the service platform to solve the problems that current loan principal and interest recovery risk are high, the information of a loan market is not opaque, the information of the lower-cost and safer fund is difficult to obtain and a supervision means is lack to go against local economic development.

The invention primarily relates to a multifunctional slow release organic fertilizer containing a heavy metal passivator and a preparation method. The fertilizer comprises the main components: thoroughly decomposed compost, a chemical nitrogen fertilizer, a biochemical inhibitor, a soil heavy metal passivating material, plant growth beneficial elements, a water retaining material and a coating liquid for coating the periphery of the organic particles. The proportion of the thoroughly decomposed compost, the chemical nitrogen fertilizer, the biochemical inhibitor, the soil heavy metal passivating material, the plant growth beneficial elements, the water retaining material and the coating liquid is 1: (0.1-0.3):(0.05-0.1):(0.01-0.2):(0.001-0.02):(0.04-0.08):(0.05-0.1). The fertilizer can reduce bio-availability of heavy metals in the heavy metal polluted soil and reduce adsorption of the heavy metals by crops and increase the content of organic matters in soil and improve the soil fertility, can promote crop growth and enhance water and fertilizer-retaining abilities of the soil, and enhance various functions of crops, for example, disease resistance, drought resistance and the like.

The invention discloses a bioactive ceramic fiber composite scaffold for bone repair and a preparation method of the composite scaffold, and relates to the field of bone repair materials. In order toovercome the shortcomings of large brittleness, difficulty in processing, unsatisfactory degradability and biological activity and the like of a traditional ceramic scaffold material, bioactive ceramics such as calcium silicate serve as a scaffold body, and the surfaces of ceramic fibers are uniformly coated with a layer of degradable biomedical high polymer materials by an impregnation-centrifugation-drying process to obtain a high-porosity, good-mechanical-property and biodegradable bioactive ceramic fiber composite scaffold material for bone repair. The bioactive ceramic materials are easily subjected to synostosis with host bones, inorganic ions released by degrading the bioactive ceramic materials can participate in and promote osteogenesis and even angiogenesis metabolism activity ofa body and have irritating or inducing functions for tissue regeneration repair, and defective bone tissue repair and functional reconstruction are promoted. Degradation products of the biomedical high polymer materials on the surface of the scaffold are harmless and can be excreted to the outside of the body by metabolism.

The invention discloses insect-inhibiting long-acting yield-increasing environment-friendly inorganic fertilizer and a preparation method thereof. The insect-inhibiting long-acting yield-increasing environment-friendly inorganic fertilizer is prepared from the following raw materials in parts by weight: 10-16 parts of traditional Chinese medicinal residual materials, 2-4 parts of tobacco waste residues, 15-25 parts of waste straws, 7-9 parts of excrement, 5-7 parts of agricultural product processing waste, 4-6 parts of kitchen waste, 3-5 parts of mineral powder, 0.5-1 part of fulvic acid potassium salt, 3-5 parts of plant ash, 0.01-0.03 part of fermenting strain, 1-3 parts of humus soil, 0.5-0.7 part of nutrient additives, 3-5 parts of shell powder and 1-2 parts of modified bamboo charcoalpowder. The inorganic fertilizer is rich in multiple nutrient substances, can be used for greatly reducing occurrence of insect pests, is environment-friendly and residue-free, has the effects of long acting, yield increasing and soil improving, can save resources and reduce use of chemicals since a great amount of industrial and agricultural wastes are adopted, and has a relatively high practical value and excellent application prospect.

The invention discloses a supervisable data anonymous sharing method and a supervisable data anonymous sharing system based on a block chain. The method comprises the steps that when a data using nodeinitiates a data sharing request to a data owning node, the data owning node generates a re-encryption key through a private key of the data owning node and a public key of the data using node, and sends the re-encryption key to a proxy server; the proxy server stores a random key used for encrypting plaintext data in advance by the data owning node and a data ciphertext at the position of the cloud server according to the re-encryption key, encrypts the random key and the data ciphertext according to a public key of the data owning node, then performs re-encryption conversion on the encrypted random key and the encrypted data ciphertext together as a ciphertext, and sends the re-encryption conversion result to the data using node; and the data use node obtains the encryption key of the to-be-shared data and the storage position of the to-be-shared data in the cloud database through decryption of the private key of the data use node, extracts the corresponding position data in the cloud database and obtains the to-be-shared data through decryption according to the encryption key.

A biotic degradation polyester graft polyphosphazene interpolymer and its preparation method are disclosed. The biotic degradation polyester graft polyphosphazene interpolymer can be prepared by open loop polymerizing of lactonic monomer initiated by linear polyphosphazene containing side group that replaced the hydroxy. The adjustment of the hydrophilia, degradation, biotic compatible and the cellular affinity can be done to satisfy the different medical purpose through choosing different kinds of the second or the third replacing group and controlling their substituted ratio. Its advantages include: excellent biotic degradation, biotic compatible and non-toxicity.

The invention relates to a programmable logical control system based on field bus communicating in a power plant distributed electric control system, discloses an implementing method of the following kernel components of the control system, including an implementing method of I / O drive, with the introduction of the I / O drive, the logical controller is convenient for concurrent accessing of a plurality of data source, and the opening and flexibility of the logical data accessing is increased; a scanning algorithm of a PLE functional block, which automatically generate scanning algorithm of a functional block, does not need artificial setting, and is suitable for tree network and ring network; a logical function block is designed based on the logical function block of the electric control system in combination with electric control features of the power plant; a logical configuration manner based on I / O point overcomes limitations of the traditional logic configuration, the entire configuration process is still more visual and readable, and the data global sharing and quality participating arithmetic is furthermore convenient. The system flexibility and application can be effectively improved by using these methods.

The invention discloses an electronic hookah, in particular to a multi-sucker electronic hookah. A hookah communicated with a shell is arranged on the bottom of the shell; at least two sucker inserting holes are formed in the shell; an electronic circuit board is arranged inside the shell; the electronic circuit board is connected with an LED (Light-emitted Diode) display screen; the LED display screen is connected with a voltage and potential regulating switch; the LED display screen and the voltage and potential regulating switch are respectively embedded with the shell; one ends of the suckers are inserted in the sucker inserting holes and the other ends of the suckers are provided with auxiliary switches; the auxiliary switches are connected with atomizers; the voltage and potential regulating switch simultaneously controls the LED display screen and the electronic circuit board; the electronic circuit board and the atomizers are in phase-shifted control; and the atomizers are in phase-shifted control by the auxiliary switches. The multi-sucker electronic hookah has a compact structure and regulation performance, and is convenient to operate, available to multiple users, and decorative.

The invention provides a Chinese herbal medicine feed additive. The Chinese herbal medicine feed additive is obtained by mixing components in traditional Chinese medicines of raw materials. The traditional Chinese medicines of raw materials comprises the following components in parts by mass: 15 parts of bark of Chinese corktree, 10 parts of stems of sargentgloryvine, 10 parts of dahurian patriniaherb, 10 parts of Chinese gall, 10 parts of pomegranate rind, 20 parts of spreading hedyotis herb, 15 parts of barbed skullcap herb, 15 parts of purslane, 25 parts of honeysuckles, 20 parts of Chinese pulsatilla roots, 20 parts of kudzuvine roots, 5 parts of coptis chinensis, 10 parts of atractylodes rhizomes, 20 parts of poria cocos, 5 parts of costusroot, 15 parts of medicated leaven, 10 partsof chicken's gizzard-membrane, 15 parts of bighead atractylodes rhizomes, 15 parts of hairy vein agrimonia herb, and 10 parts of Chinese mugwort leaves. The Chinese herbal medicine feed additive is used for feeding cultured fishes with enteritis, has the efficacy of regulating the structure of intestinal flora, and can obviously reduce the proportion and amount of harmful flora in intestinal tracts, improve the beneficial bacteria ratio of lactobacillales to bacillales, relieve the symptoms of the fishes with the enteritis, reduce the mortality of the fishes with the enteritis, and improve theacquiring rate of fishes.

The invention discloses foliar fertilizer for puer tea trees. The foliar fertilizer is prepared from the following components in parts by weight: 4 to 10 parts of fresh puer tea leaves, 8 to 21 parts of jatamans valeriana rhizome medicine residues, 8 to 21 parts of radix puerariae medicine residues, 5 to 13 parts of rhizoma dioscoreae medicine residues, 6 to 15 parts of poria cocos medicine residues, 8 to 18 parts of fructus jujubae medicine residues, 5 to 16 parts of fructus lycii medicine residues, 10 to 25 parts of Xiaoqu fen-flavor liquor vinasse and 1 to 8 parts of brown sugar. The foliar fertilizer disclosed by the invention is obtained by fermentation; the foliar fertilizer contains a large quantity of nutrient elements including amino acids, polypeptides, vitamins and the like and can be used for supplementing nutrient element deficiency caused by various factor influences; the foliar fertilizer can also be used for rapidly balancing the ecology of probiotics in the tea leaves, increasing the plant disease and insect pest resisting capability of the tea trees and improving the quality of the tea leaves; the foliar fertilizer provided by the invention is produced by adopting industrial waste materials; a preparation technology is simple and the production operability is very strong; the planting production cost of puer tea is greatly saved.

Theinvention provides an active identification card which is in a card type structure. The active identification card has a double frequency emission function, and can sense a low frequency drive signal. Two cards are integrated to be a whole by combining functions of an attendance card and a locating card into a sheet of identification card. The active identification card contains rechargeable batteries capable of performing a wireless charging and is provided with light emitting diode (LED) indicator lights which can display states of working, battery voltage shortage, battery charging and the like, so that a cardholder can know the states of the card at any time. The active identification card comprises a resonance circuit II, a resonance circuit I, a limiter circuit, a rectification voltage stabilizer, a charging management circuit, rechargeable batteries, a central processing unit (CPU), an identification data (ID) emitter of the identification card and a CPU voltage stabilizer. A control method of the active identification card and an attendance locating system utilizing the active identification card are disclosed.

The invention discloses application of a phospholipase gene PLDzeta1 in improving salt resistance of a plant. The gene PLDzeta1 is transferred to a plant through a molecular genetic transformation method, and the transformation plant with the overexpression gene PLDzeta1 is obtained. The overexpression gene PLDzeta1 remarkably improves the salt resistance of the plant. The membrane permeability and the malondialdehyde content of a leaf of the plant with overexpression gene PLDzeta1 are remarkably lower than those of a control wide group under the threat of salt, and the survival rate and the plant height are remarkably higher than those of the control wide group. The loss expression of the gene PLDzeta1 leads to remarkable reduction of the salt resistance of the plant and remarkable reduction of biological yield compared with the wild group, and the result further improves that the gene PLDzeta1 has a remarkable positive regulation effect on salt resistance. The application of the phospholipase gene PLDzeta1 in improving salt resistance of the plant provides a novel way for the seed breeding of salt-resistance molecules of the plant, and creates a novel seed material.

The invention discloses an insect-catching LED lamp which is convenient for cleaning mosquitoes, which comprises a top beam, a motor and a fixed pulley. The left side is provided with a motor, the lower end of the fixed pulley is provided with a connecting buckle, the bottom end of the connecting buckle is connected with a rear case, the bottom of the rear case is connected with a cover, and the top right side of the rear case is connected with a For the power cord, the inner cavity of the casing is provided with a crossbar, the bottom of the crossbar is provided with an LED lamp head, and the two side walls of the casing are connected with pipes. The invention drives the lampshade down to the upper end of the plant through the motor, making it easier for mosquitoes to be trapped. When lighting is needed, it can be raised to increase the lighting area. It is adjustable, and the mosquitoes enter the pipeline through the blower device and the bright light of the LED lamp bead. It is hunted and killed by the power grid, and the hunting rate is increased, which is more practical and suitable for widespread promotion and use.

The invention discloses a scaffold inclination early-warning device based on a dielectric constant change principle, and relates to the technical field of engineering early-warning equipment. The scaffold inclination early-warning device comprises an upper positioning ring, a through hole is formed in the middle of the upper positioning ring, a flange mechanism is movably connected to the bottom of the upper positioning ring, and a shell is movably connected to the bottom of the flange mechanism, a lower positioning ring is movably connected to the bottom of the shell, an anti-skid sleeve is movably connected to the outer side of the lower positioning ring, and four hinge mechanisms are movably connected to the outer side of the flange mechanism. According to the scaffold inclination early-warning device based on the dielectric constant change principle, whether a scaffold steel pipe inclines or not is detected through the variable quantity of the dielectric constant, an early warningsignal is sent out in time when the scaffold steel pipe inclines, and on-site constructors can be reminded to evacuate in time at the early stage of an accident; the problem that the optimal escape time is missed due to the fact that the scaffold cannot be reminded in time in the initial stage of deviation is avoided, and the safety coefficient of the working environment of constructors is increased.

The invention discloses composite graphene high-strength construction waste cement mortar and a preparation method thereof, the composite graphene high-strength construction waste cement mortar is prepared by mixing construction waste and standard sand as aggregate, using graphene oxide as a modifier, and then adding a polycarboxylate superplasticizer, cement and water. The performance indexes ofthe cement mortar disclosed by the invention meet the requirements that the 28-day standard compressive strength is 57.6 MPa, and the breaking strength is 9.03 MPa (tested according to GB / T17617-1999and JGJ / T70-2009); the mass loss and the strength loss of 150 times of anti-freezing cycles are both less than 5% (according to GB / T50476-2008 test); and the Cl<-> content in the product is 0.0067%, and the IRa is 0.08, and the Ir is 0.15 (tested according to GB6566-2010).

The invention relates to the field of power battery production, and in particular relates to a convenient power battery. The convenient power battery can be realized through the following technical scheme: the convenient power battery comprises a box body and a battery component installed in the box body, a mobile switching device comprises a walking device and a stagnation device, the walking device comprises a walking frame hinged with the bottom of the box body, an elastic roller connected with the walking frame, and a walking wheel arranged at the end of the elastic roller, the bottom of the box body is provided with an accommodating groove for accommodating the walking frame, and the stagnation device comprises an inclined insertion piece with an adjustable self-extension length which is connected with the bottom of the box body. The purpose of this invention is to provide the convenient power battery, according to different environmental temperature, heat dissipation or heat preservation effects can be adjusted, the electrical performance and service life of the power battery can be improved, and a mobile mode of the battery can be switched by the switching device when in rest and transport.

The invention relates to the field of production of a power battery, and in particular to a power battery with an inner cavity not liable to deform. The power battery with the inner cavity not liable to deform is implemented according to the following technical scheme and comprises a box body and a battery module, wherein the battery module is arranged in the box body, the box body comprise a box body plate, the box body plate comprises two layers of plate bodies and a hollow cavity, the hollow cavity is arranged between the two layers of the plate bodies, a protection air bag is arranged in the hollow cavity and comprises a plurality of bag bodies, a plurality of crosslinking pipes and an inflatable pipe, the plurality of bag bodies are arranged in a rectangular array, the plurality of crosslinking pipes are in parallel and are connected in series with the plurality of bag bodies, and the inflatable pipe is jointly connected with the crosslinking pipes. The invention aims to provide the power battery with the inner cavity not liable to deform, the heat dissipation or heat preservation effect can be adjusted according to different ambient temperatures, the chemical property of the power battery is improved, and the service lifetime of the power battery is prolonged; and moreover, with the deformation-resistant design, a support and buffer structure is additionally arranged, and the shape completeness of the whole battery is protected.

The invention relates to a method for improving the extracellular secretion level of recombinant protein of escherichia coli. Through a method of homologous recombination, a gene fragment including 1-4 SD sequences is integrated to a position between a promoter for encoding D-alanyl-D-alanine carboxypeptidase DacA and a DacA encoding gene. According to the method, by integrating different SD sequences to the position between the promoter of an escherichia coli DacA gene and the DacA coding gene, the expression of D, D-carboxypeptidase DacA is increased, thereby increasing the extracellular secretion level of the recombinant protein of the escherichia coli.

The invention provides a high-strength high-conductivity Cu-Ag-Sc alloy and a preparation method thereof, discloses a method for introducing a silicon carbide particle strengthening phase by designinga composite material middle layer to improve a Mg / Al layer interface, and relates to a preparation method of an aluminum / aluminum-based composite material / magnesium / aluminum-based composite material / aluminum layered material for improving the performance of the magnesium / aluminum interface. The method comprises the steps that firstly, a SiCp strengthened aluminum-based composite material of whichparticles are evenly distributed is prepared by adopting a semi-solid-state stirring casting method, then hot rolling is conducted, and an aluminum-based composite material component plate with the excellent matrix grain refinement performance is obtained; and secondly, hot pressing and annealing are conducted on metal laminated plates stacked according to the aluminum / aluminum-based composite material / magnesium / aluminum-based composite material / aluminum order. According to the method, on the one hand, the dispersion strengthening effect and the fine grain strengthening effect are generated on component layer metal; and on the other hand, the toughness of the interface area is improved, and the comprehensive performance of the composite plate can be significantly improved.

The invention belongs to the field of agricultural materials, and particularly relates to a nitrogen-doped carbon dot and rare earth-coordinated multicolor adjustable light-emitting composite material, a multicolor light-converting agricultural film prepared from the same and a preparation method thereof. By virtue of modificability of surface functional groups of nitrogen-doped carbon dots, a coordination compound of a rare earth element is connected to the surfaces of the nitrogen-doped carbon dots; due to regulatability of the fluorescence of the nitrogen-doped carbon dots, the emission wavelength of the fluorescence is controlled by changing the excitation wavelength of the fluorescence of the nitrogen-doped carbon dots, so that the energy of the nitrogen-doped carbon dots is matched with the energy of the rare earth element, the light-converting efficiency is improved, the diversity of fluorescent colors is improved, and thus the light-converting efficiency and the light-converting quality of the light-emitting composite material are improved; and the multicolor light-converting agricultural film prepared by the preparation method is simple in preparation, easy to operate, wide in raw material sources and environment-friendly, and can be applied to agricultural production for promoting growth of various crops, increasing the yield of the crops and improving the quality ofthe crops.

The invention discloses a die-cast aluminum double-alloy radiator which comprises a radiating water pipe fixing part. The radiating water pipe fixing part is provided with an arc groove, a radiating water pipe is arranged in the arc groove, the rear end of the radiating water pipe fixing part is provided with a rear shell, the side wall of the rear shell is provided with an air inlet, and an air blower is arranged in the air inlet; the bottom end of the rear shell is provided with an installation base, the installation base is provided with installation feet, the front end of the radiating water pipe fixing part is provided with a front shell, and a left-right swing blade and an up-down swing blade are arranged in the front shell; air passes through the radiating water pipe in the rear shell, and the air is heated by the radiating water pipe to form hot air which is then exhausted through the front shell. Since the left-right swing blade and the up-down swing blade are arranged in thefront shell, the blowing direction of hot air is controlled by adjusting and controlling the swing directions of the left-right swing blade and the up-down swing blade, and different requirements of people are met. The die-cast aluminum double-alloy radiator is simple in structure and good in radiating effect, and has the adjusting and controlling effect.

The invention relates to a rutile-phase vanadium dioxide film and a preparation method thereof. The preparation method comprises the following steps: directly immersing a cleaned substrate in a forerunner growth liquid containing tetravalent vanadium and transferring the substrate into a high pressure reactor; carrying out a hydrothermal reaction at 260 to 400 DGE C for 0.1 to 96 h; and carrying out epitaxial growth of the rutile-phase vanadium dioxide film on the substrate under the induction action of the substrate. According to the invention, direct epitaxial growth of the rutile-phase vanadium dioxide film on the substrate is carried out through the hydrothermal reaction under the induction action of the substrate, and the heterostructure of the rutile-phase vanadium dioxide film can be obtained without after-treatment like annealing.

The invention discloses a method for improving the extracellular secretion level of recombinant protein of Escherichia coli, belonging to the field of genetic engineering and fermentation engineering.The invention knocks out D. Alanyl-D-Alanine carboxypeptidase dacA and dacB genes (single knockout and double knockout) were cloned into recombinant Escherichia coli mutants with significantly increased extracellular secretion of recombinant proteins. Green fluorescent protein (GFP) and amylase are adopt as model recombinant proteins, which prove that that method can remarkably increase the content of extracellular proteins. The extracellular fluorescence of GFP was increased by 2.1, 2.1 and 2.7 times after single knockout and combined knockout of dacA and dacB, respectively. After single knockout and combined knockout of dacA and dacB, the proportion of extracellular amylase activity to total enzyme activity increased from 40.7% to 44.7%, 62.1% and 64.2%, respectively. The method of theinvention has important guiding significance for high-efficient secretion and production of the recombinant protein in Escherichia coli.

The invention discloses an expression vector pEGFP-N1-p53 / MAR capable of improving the transfection efficiency, a construction method and a transfection method. The expression vector pEGFP-N1-p53 / MAR is established through the manner that the human cancer suppressor gene p53 and the matrix attachment region MAR gene of chickens are inserted into an expression vector. According to the invention, the human cancer suppressor gene p53 and the regulatory sequence MAR of chickens are obtained from the peripheral blood of the early lung cancer patient and the liver tissue of the chickens respectively through RT-PCR and PCR methods, and the recombinant eukaryotic expression vector pEGFP-N1-p53 / MAR containing the EGFP gene is constructed through the means including enzyme digestion, connection, conversion and the like. Meanwhile, according to the invention, the chicken blastoderm is transfected with the expression vector pEGFP-N1-p53 / MAR, the result shows that the hatching rate of the obtained transgenic chicken achieves 56.4%. In the survival transgenic chickens, target gene p53 bands only exist in seven chickens shown by the testing, and the positive rate is 18.9%.

The invention discloses a preparation method of a dermal tissue bionic porous scaffold. The preparation method comprises the steps of: mixing a fibroin solution with alginic acid solution, then performing water vapor evaporation to form a membrane, incubating protein / alginic acid polymeric membrane in a calcium chloride aqueous solution, and finally drying to prepare the dermal tissue bionic porous scaffold. The dermal tissue bionic porous scaffold material disclosed by the invention can effectively promote wound repair and inhibit scar formation, and has a very good curative effect on open wounds including burn wounds and the like.

The invention provides a liftable and portable computer desktop which can solve problems that an existing height adjusting device of a height-adjustable portable computer desktop is inconvenient in adjustment and small in adjusting range as well as the problem that the existing portable computer desktop is prone to overturn after bearing equipment. The liftable and portable computer desktop comprises bottom plates, a desktop board and a stand column, the bottom plates are fixedly installed at the bottom of the stand column, the stand column comprises a fixing column body and an adjusting column body which are of hollow pipe fittings, the bottom of the fixing column body is fixedly installed on the bottom plate, the desktop board is installed on the adjusting column body, the adjusting column body is slidably sleeved on the periphery of the fixing column body, and a controllable air spring device is installed in the inner hole of the fixing column body with the top of a push rod fixedly connected with the adjusting column body.

The invention discloses an application of an osrodendranthus spicatus(Thunb.)C.Y.Wu leaf extract in preparation of drugs for treating renal injury. Tests confirm that OS has a regulating effect on mice chronic renal injury induced by high fat diet; different doses of OS can reduce mice renal injury induced by high fat diet to different degrees; the effect of the OS with high dose (500 mg / kg) is the most obvious, and the effect is closely related to a fact that the OS can well reduce high blood fat and oxidative stress levels in the mice with high fat diet. Therefore, the srodendranthus spicatus(Thunb.)C.Y.Wu leaf extract has wide application in preparation of the drugs for treating renal injury.

The invention discloses application of mPGES-2 as a drug target for developing or screening or preparing drugs for treating and / or preventing diabetes mellitus. The invention puts forward that the mPGES-2 is the drug target of the diabetes mellitus for the first time. Experiments show that by knocking out the mPGES-2, blood sugar of normal-diet mice and high-fat-diet mice is remarkably improved, pancreatic proliferation of the mice is remarkably promoted, meanwhile, differentiation of pancreatic beta cells is promoted, and generation of insulin by pancreas islets is promoted, so that glycometabolism of the mice is improved. By virtue of overexpression of the mPGES-2, generation of cAMP of the pancreas islets can be obviously inhibited, so that secretion of the insulin is inhibited. The experiments show that the mPGES-2 is capable of regulating and controlling the blood sugar, can be taken as the target for treating the diabetes mellitus and has important significances to medicinal development, prevention and treatment of the type of diseases.

The invention discloses a leaf surface spraying agent, a preparation method thereof and a method for controlling the content of cadmium in rice. The leaf surface spraying agent comprises 1 to 50 mass parts of silica micropowder, 0.5 to 20 mass parts of (3-mercaptopropyl)trimethoxysilane, 0.01 to 0.1 mass part of isothiocyanate, 0.5 to 20 mass parts of cosolvent, 0.05 to 1 mass part of surfactant and 1000 mass parts of water. The silica micropowder in the leaf surface spraying agent can inhibit the transfer of the cadmium to the rice; the (3-mercaptopropyl)trimethoxysilane can reduce the agglomeration of SiO2 in water so as to increase the specific surface area of the SiO2, and meanwhile, active groups, such as mercapto group, contained in the (3-mercaptopropyl)trimethoxysilane are favorable to complexing heavy metals and reducing the heavy metal absorption of the rice; the isothiocyanate can release H2S, and an exogenous H2S signal has a regulating effect on the physiological process of a plant and can reduce the cadmium absorption of the rice; by combining and using the silica micropowder, the (3-mercaptopropyl)trimethoxysilane and the isothiocyanate in the leaf surface spraying agent, the content of cadmium in the rice can be remarkably reduced; moreover, the leaf surface spraying agent is convenient to use, low in cost, and convenient to popularize and apply.