337results about How to "Avoid environmental pollution" patented technology

The present invention relates to an electric flue-cured tobacco. It includes a storage tank filled with extractant and an atomization device. The electric flue-cured tobacco also comprises a device for flue-curing tobacco, which includes a heating mechanism and a heated chamber for loading cigarette or tobacco. The heating mechanism comprises a heating element and a heater circuit for controlling the heating element to be heated to a setting temperature range. An inlet of the heated chamber is connected to an outlet of the atomization device, and its outlet is connected with an opening for suction nozzle. When the electric flue-cured tobacco is working, the extractant is atomized by the atomization device and then guided into the heated chamber. The heat produced by the heating element is applied to the cigarette or tobacco in the heated chamber to generate nicotine. The nicotine and atomized extractant are mixed together and then sucked out through the opening for suction nozzle. By adopting the structure mentioned above, since the nicotine in the form of atomization can be easily absorbed by the lung, most of the gas that smokers blow off is the extractant. Therefore, the environmental pollution and passive smoking for people around can be reduced. On the other hand, it can satisfy smokers' taste.

The invention relates to an edible starch-based food packaging film and a preparation method thereof. The edible starch-based packaging film with high mechanical strength, barrier property, ageing resistance and heat sealability is prepared from a main film-forming raw material stabilized crosslinking compound modified starch, and auxiliary materials such as food grade plasticizers, lubricants, reinforcers, stabilizers and the like through high speed stirring and mixing, twin-screw extrusion granulation and single-screw extrusion blow molding. The preparation method has the characteristics of low energy consumption, high production efficiency and suitability for continuous industrialized production. The film has the advantages of edibility, full-degradable property, wide application for inner packaging of foods and no environmental pollution caused by non-degradable food packages.

Disclosed is a self-regulating hydrogen gas generator for a hydrogen fuel cell. The self-regulating hydrogen gas generator includes a fuel tank, defining an inner space having a designated volume, provided with a hydrogen outlet communicating the inner space, a fuel solution, containing a hydrogen storing material, stored in the fuel tank, and a catalyst contacting the fuel solution for generating hydrogen gas, wherein the catalyst fills a catalytic reactor, provided with a closed portion for interrupting the contact between the catalyst and the fuel solution, and an opened portion contacting the fuel solution, so that the generation and interruption of hydrogen gas are actively regulated based on the increase and decrease of the pressure of the fuel tank.

The invention discloses a new manufacturing technique of a xylose and relates to a technique for manufacturing the xylose. The technique adopts the technology of electrodialysis recycling sulphuric acid, a bag adopted by a nanofiltration concentration device and a special nanofiltration separation system concentrates the liquid in the technique for manufacturing the xylose at normal temperature, therefore water and other impurities can be removed from the product; the manufacturing technique comprises: 1. pretreatment, 2. hydrolyzation, 3. decoloration, 4. electrodialysis, 5. ion exchange, 6. nanofiltration, 7. concentration, 8. ferment, 9. crystallization, 10. centrifugation, and 11. drying, then the high purity xylose is obtained. The new manufacturing technique of the xylose can not only recycle 50 percent sulphuric acid in the hydrolyze liquid, but also can recycle waste acid and spent caustic produced in the regenerative process of duolite, therefore the dosage of sulphuric acid can be saved and the environment pollution is avoided. The technique solves the problems of scale formation in device in the neutralizing deacidification technique, large usage of duolite in deacidification technique, large usage of devices, large investment, large consumption of acid and alkali, high costs and the like; thus improving the device utilization rate and the service life, decreasing the ash and the acid contents in the hydrolyze liquid, improving the quality of the hydrolyze liquid and enhancing the product quality and separating efficiency.

The invention discloses a processing method of fish collagen oligopeptide, which comprises the following steps: delimed and degreased dry scales are selected as raw material, after being treated with cleaning, pretreatment, enzymolysis, filtration, decolorization, taste escaping, desalinization, aseptic filtration, concentration, and spray drying, fish collagen oligopeptide powder is obtained; according to dry basis, the fish collagen oligopeptide powder contains: protein content of no less than 95 percent, ash content of less than 0.5 percent, and average molecular weight of 700Dalton. The product processed by the method of the invention has the advantages of high quality, colorlessness, no bitter taste or stink, low salt content, no poisonous or side effect, and short enzymolysis time, the resin filling used during the adsorption process is renewable and can be repeatedly used for a plurality of times, and the problems of wasting of resources and high ash content of the product caused by using the disposable activated charcoal are avoided, thus being widely applied in the fields of food, health products, medicine and cosmetics, etc.

Belonging to the technical fields of biology and food, the invention relates to a preparation method of an active lactobacillus pickle pickling liquor. The method includes: taking a fermentation pickling solution of pickled pepper, a fermentation pickling solution of pickled capsicum frutescens and cold boiled water as raw material water, subjecting the pickling solutions to rough filtration, and mixing them with the cold boiled water uniformly, then carrying out cooling and high speed centrifugation degerming, and adding a direct vat set lactobacillus starter, thus obtaining the pickling liquor. The method provided in the invention realizes standardized preparation of pickling liquor, ensures the viable count of lactobacilli in the pickling liquor, endows the newly prepared pickling liquor with the flavor of aged pickling liquor and better flavor. At the same time, the use problem of the pickling solutions of pepper and capsicum frutescens is solved, the environmental pollution caused by emission and the potential safety hazard caused by repeated use in the next year can be avoided, so that the biological safety, quality and homogeneity of the product are significantly improved. Further, upgrading and industrial, large-scale and standardized production of traditional active lactobacillus pickles can be realized.

Provided is a reusing method for galvanization sintered neodymium iron boron waste. A galvanization layer is removed through a hot deplating method, then milling, forming and sintering are carried out, neodymium iron boron materials of middle-high marks are prepared; for galvanization sintered neodymium iron boron waste with the ratio of galvanization layer weight to magnet weight smaller than 0.5%, zinc can be regarded as an impurity which cannot be removed, hot deplating is not carried out, crushing and milling are directly carried out, then pressing forming and sintering are carried out again, and neodymium iron boron materials of middle-low marks are prepared. According to the reusing method, environment pollution caused by chemical deplating is completely avoided, the reusing process of the valuable elements in the neodymium iron boron waste is simple, and rare earth element loss is low.

The invention relates to a method for recycling, cleaning and granulating waste mulching films. The method comprises the steps of cleaning and granulating. In the cleaning step, the recycled waste mulching films are classified, sorted and pretreated, are conveyed into a thin film crusher for crushing, are conveyed into a frictional cleaner through a spiral conveyor I for cleaning, are conveyed to a rinsing tank through a spiral conveyor II for secondary cleaning, are conveyed to a squeezing machine through a spiral conveyor III, and are conveyed into a storage bin through a pneumatic conveying system I. In the granulating step, the waste mulching films are conveyed to a cutting compaction cylinder through a conveying belt for treatment, treated materials are automatically forced to be pushed into an SJ150/26 single-screw extruder, a melt is extruded through a hydraulic screen exchanger and is directly cut into uniform particles on a mold surface through a water ring granulator, the particles are conveyed into a centrifugal dehydrator for dehydration treatment, and the dehydrated particles are conveyed into the storage bin through a pneumatic conveying system II, and are bagged and stored at an outlet of the storage bin. According to an advanced method for recycling, cleaning and granulating the waste mulching films, the environment pollution is avoided, and resources are recycled.

Disclosed herein is a reaction container plate which prevents the entry of foreign matter from the outside and the pollution of an outside environment. A reaction container plate (1) includes a sealed reaction container (5), a reaction container channel (15) connected to the reaction container (5), a sealed container (17) provided separately from the reaction container (5), a sealed container channel (17a) connected to the sealed container (17), a syringe (33) for sending a liquid, a switching valve (47) for connecting the syringe (33) to the introduction channel (15) or the sealed container channel (17a), and a sealed container air vent channel (17b) of which one end is connected to the sealed container (17). When the syringe (33) is connected to the sealed container (17) via the switching valve (47) to inject a liquid contained in the syringe (33) into the sealed container (17) and to suck a liquid contained in the sealed container (17) into the syringe (33), a gas contained in the sealed container (17) is moved between the sealed container (17) and the sealed container air vent channel (17b).

The invention provides a composite pre-mix material used for pigs, which is characterized by comprising components in the following weight percent: 20 percent to 50 percent of calcium carbonate, 1 percent to 25 percent of calcium hydrophosphate, 2.01 percent to 27 percent of synthetic amino acid, 0.5 percent to 17 percent of organic microelement, 0.001 percent to 0.2 percent of potassium iodide with 5 percent of purity, 1.1 percent to 5.5 percent of enzyme preparation, 5 percent to 10 percent of salt, 0.2 percent to 2 percent of composite multi-fiber used for pigs, 0.3 percent to 2 percent of antioxidant, and 1 percent to 40 percent of carrier. The invention also provides the preparation method of the composite pre-mix material used for pigs. The product of the invention reduces the addition of phosphorus and improves the ration nutrient digestion rate by adding the enzyme preparation , so as to reduce the emission of nitrogen and the phosphorus; provides microelements, such as copper, iron, zinc, manganese, selenium, etc. by adding composite amino acid chelate complex, which not only greatly reduces the emission of the microelements and prevents environmental pollution, but also prevents the sediment of the microelements in pork, and ensures the eating safety of the pork.

The invention provides a paint removing method and paint removing equipment for a surface of a metal hanging rack. Liquid-nitrogen soaking and metal particles are utilized to perform paint removal treatment on a paint resin coating on the surface of the metal hanging rack, so that the problem that paint removing effect is poor and environmental pollution is caused due to the fact that the metal hanging rack adopts an existing paint removing method is solved. The paint removing method comprises a liquid nitrogen soaking step and a multi-stage variable-frequency particle colliding step; the paint removing equipment comprises a ring-shaped rail, a self-propelling car, a liquid nitrogen slot, a metal particle impact bin and a control system; the ring-shaped rail is horizontally suspended above the liquid nitrogen slot and the metal particle impact bin; liquid nitrogen is contained in the liquid nitrogen slot; the self-propelling car is arranged on the ring-shaped rail, and can move along the ring-shaped rail; and the self-propelling car is equipped with a clamping mechanism used for clamping the metal hanging rack, a hoisting mechanism used for controlling the clamping mechanism to move up and down, and a drive mechanism used for driving the metal hanging rack to rotate along the longitudinal central shaft thereof.

The invention discloses a light fabric conveying belt. By means of the light fabric conveying belt, the problems that when existing conveying belts are used for conveying light fabrics, the fabrics are easy to spatter, and conveying is not conducted smoothly are solved. According to the light fabric conveying belt, a first conveying support is fixedly connected to a base; a second conveying support is mounted at the upper side of the first conveying support; a main conveying belt and a subsidiary conveying belt are assembled onto the first conveying support and the second conveying belt in a rotary manner correspondingly; the subsidiary conveying belt and the main conveying belt rotate synchronously in opposite directions, so that a clamping type conveying channel is formed; multiple first material shifting strips are arranged at the outer side of the main conveying belt, multiple second material shifting strips are arranged at the outer side of the subsidiary conveying belt, and the first material shifting strips and the second material shifting strips are arranged in a spaced manner; and adjustment mechanisms are mounted at the two ends of the subsidiary conveying belt correspondingly. By means of the main conveying belt and the subsidiary conveying belt of the light fabric conveying belt, the light fabrics can be clamped in the conveying channel formed by the two conveying belts and conveyed. The light fabric conveying belt has the beneficial effects that the structure is simple; the fabrics cannot spatter easily; conveying is conducted smoothly; and conveying efficiency is high.

The invention relates to a method for synthesizing a nanometer HMS mesopore molecular sieve. The method has the concrete steps that template, water, ethanol (EtOH) and 1-butyl-3-methyl ionic liquid imidazole tetrafluoroborate ionic liquid are mixed for 5 to 60 min, and a silica source is dropped under the mixing to get a reaction precursor glue solution; the reaction precursor glue solution is continuously mixed to react for 12 to 36 hours to get a sol gelation reaction product; the sol gelation reaction product is filtered or centrifugalized and washed, dried at 50 DEG C for 24 hours, at last roasted at 500 to 650 DEG C of air for 4 to 10 hours, and the template and the ionic liquid are eliminated to get the nanometer HMS mesopore molecular sieve. Because the ionic liquid of the method relates to a nonvolatile green good solvent, the method has the advantages of green environmental protection, environmental pollution prevention and simple preparation technology, and uniform and separated particles of the prepared nanometer HMS mesopore molecular sieve.

A recycling method of abrasive dust in the brake plate preparation process is provided. The brake plate is compounded by 5 percent to 10 percent of adhesives, 10 percent to 30 percent of reinforced material, 10 percent to 35 percent of friction performance regulator, 8 percent to 25 percent of stuffing and 25 percent to 65 percent of grinding dust material on quality. Under the unit pressure of 15 to 20MPa, the prepared and weighed friction material is poured into a plow harrow mixer to be evenly stirred for 5 minutes and then put into a mould to be suppressed for 8 to 10 minutes. The method has the following heat treatment procedures: keeping for 1 hour at 140 degrees centigrade, keeping for 2 hours at 165 degrees centigrade, keeping for 2 hours at 180 degrees centigrade, keeping for 1 hour at 195 degrees centigrade and then cooling to normal temperature. The invention recycles the waste reasonably, avoiding environmental pollution and obviously improving the friction coefficient stability and consistency of the product. The friction coefficient fluctuation is reduced 15 percent and the heat fading is small. The stability of the friction performance is improved more than 15 percent and the abrasion wear is reduced more than 20 percent. At the same time, the manufacture cost is reduced 15 percent and the economic benefit is also improved.

The invention discloses a porous silicon nitride ceramics composing prescription and a method for the products thereof, containing the following components by weight: 50-70 per centsilicon nitride powder, 5-30 per cent bentonite, 0-10 per cent sintering additives and 20-30 per cent water. The sintering additives, contain at least one of Y2O3, Al2O3 and MgO and the method includes: weighing the components except water before placing into a ball mill for dry mixing-grinding to make a mixed powder which is then put into a wheel roller for wheel grinding and kneading to obtain a pug; putting the pug into an extruder for extrusion forming to obtain a shaped body; then drying the shaped body before putting into an atmosphere oven where the shaped body is heated to a temperature of 1700-1850 DEG C in the nitrogen at a heating rate of 10 DEG C/min and then insulation sintered for 1 to 3 hours at a nitrogen pressure of 1-6 atmospheric pressure to obtain a sintered body . The porous silicon nitride ceramics of the invention can be widely used as matrix of filters for gas separation at high temperature and in corrosive atmosphere and as heat-resistant or enhanced materials for power generation gas turbines, engines and space shuttles.

The invention relates to a preparation method and an application of alkylated functional graphene. The preparation method comprises the steps of dispersing graphene oxide prepared by an improved Hummers method into a micromolecular ketone compound and water mixed solution (0.1-5mg/mL) in different proportions according to a stoichiometric ratio, conducting ultrasonic oscillation and stripping for 1-8h at a room temperature, separating, and obtaining the functional graphene. The functional graphene and PA66 (Poly A 66) as raw materials, a graphene/PA66 nano composite is obtained by a fusion blending method, and the weight percentage of the functional graphene in the composite is 0.01-1%. The preparation method of the modified graphene is simple, convenient and quick, and the dispersity of the graphene in a polymeric matrix can be improved significantly. The invention further discloses a preparation method of the graphene/PA666 nano composite. The mechanical property, antistatic property, moisture absorption and thermal stability of the prepared nano composite can be improved obviously.

The present invention provides a catalyst comprising a composite of a heteropolyacid impregnated on a support for the synthesis of 2- and 4-picolines and a process for the preparation thereof and use thereof for the synthesis of 2- and 4-picolines.

The invention relates to a waste gas purifying and weighing integrated reaction kettle device which comprises a kettle body, a waste gas treating and purifying device and a weighing device arranged at the top of the kettle body. A kettle cover is arranged at the top of the kettle body, a material inlet, a gas discharging hole and a thermometer sleeve are arranged on the kettle cover, and the waste gas treating and purifying device is positioned at the upper end of the kettle body and fixed through a mounting frame. By arranging a waste gas filtering layer, a waste gas adsorbing layer and a waste gas ventilating layer, a lot of high-concentration organic waste gas generated in the process of reaction for preparing adhesive resin can be treated and absorbed to reach discharging standards; a ventilating wall plate having a certain inclination angle is arranged, so that noise in the process when a fan runs can be lowered. The waste gas purifying and weighing integrated reaction kettle device is compact in structure, high in automation level and convenient and simple to operate.

The invention provides a method for recycling metallic lithium from waste lithium ion batteries. According to the method, an extraction system is formed by ionic liquid and tributyl phosphate, and selective extraction is conducted on aqueous phase leachate containing nickel ions, cobalt ions, manganese ions and lithium ions, so that the recovery rate of the metallic lithium is effectively increased. The volume ratio of the ionic liquid to the tributyl phosphate is not greater than 1: 1; and the pH value of the aqueous phase leachate containing the lithium ions is not greater than 7. The methodis easy to operate and efficient; after reverse extraction, the extraction system can be utilized cyclically; compared with a traditional wet method recycling process, the defects that plenty of acid-base solutions are consumed, and a great amount of waste water is generated are effectively avoided; and the good application prospect is achieved.

The invention discloses a vegetable oil based insecticidal acaricide, which comprises (by weight percent) gum spirit of turpentine 5-75%, wintergreen oil 0-55%, elliptone 0.01-5%, and balancing adjuvant.

The invention discloses a process for wholly recycling valuable metals in waste SCR denitration catalysts through a wet method. The process is mainly used for common SCR denitration catalysts with TiO2 as carriers and V2O5-WO3(MoO3) and other metal oxides as main active ingredients. Different precipitants are added to the pretreated waste SCR denitration catalysts, and TiO2 powder, V2O5 crystals and WO3 or MoO3 are sequentially obtained through procedures such as filtration and calcination. By the adoption of the process, the valuable metal oxides of the waste SCR denitration catalysts can be effectively recycled, and considerable economic benefits are acquired while environmental problems are solved and resources are saved.

The invention belongs to the field of resource utilization of natural plant fibers, and in particular relates to a method for preparing coconut shell fibers by removing pectin from a coconut shell through steam explosion. The method comprises the following steps of: cutting the coconut shell into blocks for steam explosion processing; and rinsing and bleaching the blocks to obtain high-quality coconut shell fibers. Steam is used as a medium and any chemical reagent is not added in the steam explosion process, so that the method is clean and causes no pollution; over 80 percent of the pectin and hemicellulose in the coconut shell fibers are degraded by the steam explosion processing; lignin is partially degraded; meanwhile, the coconut shell fiber bundle is completely separated from other components; other tissues apart from the fibers can be removed by rinsing; and the coconut shell fibers are torn into loose structures in the steam explosion process, so the bleaching, oil supply and loosening of the fibers are facilitated and the quality of the fibers is improved. The invention provides a clean low-cost method for preparing the coconut shell fibers.

The invention provides itraconazole nanocrystals and a preparation method and application thereof. Acid phase in which itraconazole is dissolved is dropwise added into alkaline phase to over-saturate the itraconazole; the itraconazole molecules are aggregated into amorphous nanocrystalline particles in the presence of a high molecular stabilizer to form a stable structure with itraconazole nanocrystals as a core and the high molecular stabilizer as a shell; and both the solubility and the dissolution rate of the itraconazole nanocrystals are greatly improved compared with those of normal itraconazole nanoparticle suspension. A hydrophilic fragment of the high molecular stabilizer, which is extended into the water, improves the hydrophobicity of the surfaces of the itraconazole nanoparticles, so that the high molecular stabilizer is more easily moistened and dissolved; and the high molecular stabilizer serving as the shell enhances the adhesion between the medicament particles and gastrointestinal mucous membrane, is favorable for improving the bioavailability and reduces the influence of a diet state on the bioavailability. The method of the invention has the advantages of no use of toxic solvent, simple preparation process, low cost and easy industrialization.

The invention discloses a bio-fermentation onion skin extractum and a production method thereof. The production method is characterized by comprising the following steps of: mixing 87 to 96 weight percent of onion skin powder, 2 to 5 weight percent of lactic acid bacteria fermenting agent and 2 to 8 weight percent of yeast fermenting agent; standing and culturing the mixture with water moisture of between 60 and 65 percent at temperature of between 33 and 36 DEG C for 10 to 18 hours to obtain fermented onion skin powder; heating the fermented onion skin powder to temperature of between 60 and 100 DEG C, refluxing, extracting, filtering, reducing pressure, drying and smashing, thus obtaining the bio-fermentation onion skin extractum. The bio-fermentation onion skin extractum produced by using the method is applicable to patients with hypertension, hyperlipidemia and diabetes mellitus and can be used as burdening of foods, such as bread, desserts, beverage and the like; the onion skin extractum is fermented by probiotic bacteria, so active ingredients of onion skin can be promoted, the quality of the product is improved, and the resource utilization rate is increased effectively; and the product with extremely high application value can be obtained, the environmental pollution is avoided, the cost is reduced and the resources are saved.

The invention provides a non-transformer wireless mouse device. The non-transformer wireless mouse device of the invention utilizes electromagnetic induction to independently supply the power, comprising an idler wheel which can be rotated, a magnetic induction generator which is driven via the rotation of the idler wheel to generate the electricity energy by using the electromagnetic induction, an energy storage device for storing the electricity energy generated by the magnetic induction generator, an information processing and signal transmission device which responds to the operation of the user to process the information and transmit the signal by using the electricity energy supplied by the energy storage device. The wireless mouse device of the invention supplies the power continuously and stably, charges the mouse under the circumstance of normally using the mouse, not only brings the convenience for the user, but also is environment-friendly.

The invention discloses a shared packaging box, a logistics system and a logistics method. The shared packaging box comprises a box body, a cover body arranged on the box body, electronic locks arranged on the box body and the cover body respectively as well as a box control module, a box positioning module, an identity information module, a box information receiving module and a box information sending module which are arranged on the box body, wherein the box control module is connected with other modules and the electronic locks. The logistics system comprises the shared packaging box, a reception desk, a delivery terminal, a receiving terminal and a logistics terminal, and the reception desk is connected with the shared packaging box, the delivery terminal, the receiving terminal and the logistics terminal. The logistics method is a method for completing goods transportation through the shared packaging box and the logistics system. Repeated use of package of delivered goods is realized through the shared packaging box and in combination with the logistics system, resource waste and environment pollution are avoided, the whole process is safe, efficient, secret and traceable.

The invention provides a method for modifying wood and bamboo wood through biopolymer-chitosan. The method is characterized in that 1-ethyl-3-methyl imidazole chloride ionic liquid serves as a solvent, the chitosan is dissolved under the heating condition, and uniform and stable chitosan liquid is formed; and then fast-growing wood or bamboo wood is subject to modified treatment, the chitosan liquid with the 1-ethyl-3-methyl imidazole chloride ionic liquid as the solvent is easily diffused to the surface layers of wood/bamboo materials, and uniform chitosan layers are formed in wood/bamboo base materials after heating and drying. The modified wood/bamboo wood has the better size stability and antifungal and antibacterial performance; and meanwhile, the hardness is improved to a certain degree.

The invention discloses a process for preparing edible vinegar by utilizing byproduct of solid-state method white spirit brewage characterized in that, using pot bottom water and yellow water in white spirit distillation as the main ingredients of the raw material, carrying out organoleptic indicator and physicochemical index detection, then mixing the two ingredients to make the total acetic acid content in the miscible liquid between the range of 2.5-3.5g/100ml.

The invention provides a method for efficiently preparing 5-hydroxymethyl furfural (HMF) utilizing biomass widely existing in a natural world as a raw material. The method includes the following steps: utilizing a two-phase system composed of low-boiling point organic matter and water, adopting acid salt of sulfuric acid and sulfuric acid metal normal salt as a catalyst in synergy mode to form a catalyst system, adding the biomass raw material capable of being degraded to hexose to a reaction system and preparing the HMF by reaction. The reaction process of the method has high HMF selectivity. The catalyst is low in price, mild in operation condition, simple in process and low in separation energy consumption. The biomass raw material with a wide source is utilized as the reaction raw material, preparation of biomass-based chemical and alternative fuel with the biomass as the raw material can be favorably promoted, and the method has high industrialized prospect.

The invention discloses a cadmium telluride film solar cell and a preparation method thereof. A structure of the cadmium telluride film solar cell is that the cell comprises a substrate with a conducting layer, and the substrate is sequentially deposited with a cadmium sulfide layer, a cadmium telluride layer, a tellurium-rich layer, a back contact layer and a back electrode. According to the method, a treated low-toxicity compound cadmium is adopted as a cadmium source, and treated tellurium or telluride is adopted as a tellurium source to prepare the cadmium telluride film solar cell; the cadmium source and the tellurium source undergo a chemical reaction in a certain molar ratio to prepare cadmium telluride particles with uniform particle size; and then the cadmium telluride particles are purified, cadmium telluride and a low boiling-point solvent containing polyvinylidene fluoride are mixed to obtain sol, and a cadmium telluride film is prepared by a coating method. The method prevents human bodies from contacting high-toxicity cadmium element and cadmium steam, and also avoids environmental pollution at the same time.