231results about How to "Many adsorption sites" patented technology

The invention discloses a thin film field effect transistor type gas sensor and a preparation method thereof. The sensor is a thin film field effect transistor with a bottom gate top contact type structure or a bottom gate bottom contact type structure. A thin film field effect transistor with a bottom grid top contact structure is taken as an example. The transistor comprises a substrate, a gateinsulating layer and a channel active layer from bottom to top. The channel active layer is a quantum dot thin film. A source electrode and a drain electrode are deposited above the substrate. A gateelectrode is further led out of the substrate. The internal composition, the structure, the overall process of the corresponding preparation method and the parameters during all steps of the preparation method of the thin film field effect transistor type gas sensor are improved. The quantum dot thin film serves as a channel active layer and a gas sensitive layer at the same time, and the gas response of multiple parameters is comprehensively regulated by utilizing the grid bias voltage. As a result, the prepared gas sensor is high in sensitivity, low in power consumption and high in selectivity. The effect of detecting low-concentration target gases, such as NO2 and H2S, is achieved.

The invention relates to a preparation method and an application of magnetic activated hydrothermal biochar microspheres. The method comprises the following steps: subjecting aquatic plant powder, an iron salt catalyst and deionized water to a hydrothermal reaction in a reaction kettle to prepare the hydrothermal biochar microspheres; completely mixing the hydrothermal biochar microspheres, FeCl3, ZnCl2 and the deionized water and drying the mixture; placing the dried mixture sample into a box type atmosphere furnace, performing final temperature pyrolysis at the target temperature under the condition of nitrogen protection, so as to prepare the magnetic activated hydrothermal biochar microspheres. The magnetic activated hydrothermal biochar microspheres prepared by the method can effectively adsorb and remove a large amount of heavy metal lead and copper in water, the composite material prepared by the method can also be added into soil containing excess amounts of lead and copper, the biological effectiveness of lead and copper in the soil is reduced, and the purpose of controlling heavy metals is achieved.

The invention discloses a field effect transistor gas sensor and an array preparation method thereof. The field effect transistor (FET) gas sensor is a gate-sensitive FET gas sensor with a gate electrode modified by quantum dots, and a gate-sensitive electrode layer (5) of the FET gas sensor is of a two-layer composite structure or of a single-layer structure made of a composite material. The two-layer composite structure comprises a metal film layer and a quantum dot layer deposited on the surface of the metal film layer. The single-layer structure made of a composite material is specificallya single-layer structure made of a composite material formed by combining quantum dots and a metal or metalloid material. According to the invention, improvement is made on the internal composition and structure of the gate-sensitive FET, the corresponding preparation method and the like, quantum dots are used as a gate electrode and a gas sensitive layer at the same time, and the bias voltage ofthe gate electrode and the channel modulation effect are regulated and controlled by utilizing the adsorption characteristic of a quantum dot gate-sensitive electrode to different gases. A room-temperature gas sensor with high sensitivity, low power consumption and high selectivity can be obtained, and low-concentration target gases (such as H2) can be detected.

The invention provides a rare metal-based sludge activated carbon and application thereof in the removal of sulfur, ammonia and phosphorus. The rare metal-based sludge activated carbon includes sludge activated carbon and metal elements such as manganese, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium and the like, and is specifically prepared by a method comprising the following steps: mixing pyrolusite powder with activated sludge, adding a zinc chloride compounded activating agent into the mixture, activating the mixture at a high temperature, carbonizing the mixture to obtain pyrolusite compounded activated sludge, mixing the activated sludge with rare earth oxide powder and a chelating agent after the activated sludge is modified by potassium hydroxide solution, heating the mixture in a microwave oven, carbonizing the mixture to obtain rare earth compounded activated sludge, and mixing the compounded activated sludge to obtain a product. The rare metal-based sludge activated carbon prepared by the method has the advantages of high activity, high porosity, uniform pore size distribution, high adsorption capacity, capability of chelating a plurality of metals and microorganisms, high capacity of adsorbing sulfur, ammonia and phosphorus and high rate of removing the sulfur, the ammonia and the phosphorus in sewage and waste.

The invention relates to a fluoride-removal adsorbing material for removing fluorides in drinking water and in particular relates to an active aluminum oxide fluoride-removal adsorbing material with different surface characteristics as well as a preparation method and an application of the active aluminum oxide fluoride-removal adsorbing material. The active aluminum oxide fluoride-removal adsorbing material with different surface characteristics is obtained by carrying out the processes including sufficient chemical reaction, ageing, drying, grinding and the like into an aluminum salt aqueous solution, a chlorine salt aqueous solution and an alkali aqueous solution, wherein the specific preparation process parameters are determined by water quality chemical characteristics of to-be-treated water. Based on active aluminum oxide fluoride-removal adsorbing material with different surface characteristics, the actions including complexing, condensing and the like are carried out to transfer free fluorides in the water into complexing fluorides, so that the adsorbing performances of the active aluminum oxide fluoride-removal adsorbing material with different surface characteristics are greatly improved, the adsorbing period is prolonged and the operation cost is reduced. Fluorides in the drinking water are removed by adopting the method disclosed by the invention, so that the treated water can reach the national drinking water standards.

The invention relates to a chlorophenol graphene-based molecularly imprinted solid-phase extraction column, which comprises an empty column, a sieve plate and a filling material. The filling material is formed by mixing chlorophenol graphene molecularly imprinted nanoparticles and a conventional solid-phase extraction packing at the mass ratio of 1: 1-10. According to the chlorophenol graphene molecularly imprinted nanoparticles, a magnetic Fe3O4 high-molecular material is supported on the surface of graphene as a function unit, and a target chlorophenol compound to be adsorbed is used as template molecule. Meanwhile, the invention also relates to a preparation method and an application of the chlorophenol graphene-based molecularly imprinted solid-phase extraction column. The chlorophenol graphene-based molecularly imprinted solid-phase extraction column has large specific surface area, many adsorption sites, strong specific selectivity and good enrichment effect, can be used in enrichment of residual trace amount of chlorophenol compounds in an environmental water sample, and can achieve high enrichment factor and can remarkably reduce matrix effects. Meanwhile, the preparation method of the molecularly imprinted solid-phase extraction column is simple, technological conditions are stable, and production cost is low.

The invention discloses a biochar-chitosan composite as well as a preparation method and an application thereof. The preparation method comprises steps as follows: (a) a biomass material is mixed withsoluble iron salt and a sulfuric acid solution, a mixed solution is obtained, the mixed solution is subjected to ultrasonic treatment, filtration and drying, and a biochar material head product BC isobtained; (b) the head product is subjected to high-temperature pyrolysis, and a biochar material L-Fe is obtained; (c) a certain mass of chitosan powder is dissolved in an acetic acid solution, a mixed solution is formed, a certain mass of biochar material L-Fe samples are taken and added to the mixed solution, the mixture is heated and stirred in a water bath pot, the PH value is adjusted to bealkaline, filtration and drying are performed, and a biochar-chitosan composite LC-Fe is prepared. The method adopts a simple preparation process and has no secondary pollution, and the prepared modified biochar material has high adsorption capacity and adsorption rate for Cr<6+> and Cu<2+> and has wide application prospects in the aspects of wastewater treatment and purification.

The invention discloses a magnetic ordered mesopore composite material, as well as a preparation and application thereof. The preparation method of the material comprises the following steps: modifying the surfaces of cobalt ferrite nano particles with a cationic surfactant, namely hexadecyl trimethyl ammonium bromide (CTAB), uniformly mixing the product with a segmented copolymer, namely EO130PO70EO130 (F108) and CTAB in an alcohol water system, and adding tetraethyl orthosilicate. The composite material is of a spherical microstructure with uniform size under the observation of a transmission electron microscope, and the magnetic nano particles are coated with the inside of MCM-48 silicon dioxide balls; the magnetic ordered mesopore composite material which is synthesized by the method has excellent magnetic property, maintains large specific surface area and pore volume, and can be applied to the field of adsorption, separation, catalysis, information storage, biological medicine, and the like.

The invention provides molecularly imprinted polymeric microspheres as well as a preparation method and application thereof. The preparation method specifically comprises the following steps: (1) weighing niacinamide and methacrylic acid and dissolving into a solvent; and carrying out ultrasonic treatment and standing to obtain a mixed solution; (2) adding divinylbenzene and 2,2'-azobis(2-methylpropionitrile) into the mixed solution in the step (1), and carrying out ultrasonic treatment; and after introducing nitrogen gas, sealing and stirring to obtain a polymer; and (3) putting the polymer into an eluting solution, centrifuging after carrying out ultrasonic oscillation, and washing and drying to obtain the product. The preparation method provided by the invention is simple and convenient and the prepared molecularly imprinted polymeric microspheres have high adsorption rate.

The invention discloses a preparation method of a high-activity SnO2-TiO2 composite nanometer photocatalyst, which comprises the following operating steps: (1) mixing tetrabutyl titanate, tetrabutyl titanate and glacial acetic acid, adding dilute nitric acid and water, stirring, and standing; (2) adding the SnCl4.5H2O solution to the mixed solution, stirring and ageing, wherein the molar ratio of titanium to tin in the mixed solution is (10-80):1; (3) putting the aged substance into an autoclave for constant temperature treatment for 22-27 h, and cooling to the room temperature; (4) using absolute ethyl alcohol to repeatedly wash the obtained cooled product, performing centrifugal separation, drying and grinding the separated product to obtain the high-activity SnO2-TiO2 composite nanometer photocatalyst. According to the invention, the high-activity SnO2-TiO2 composite nanometer photocatalyst is prepared through the sol-solvothermal method; the prepared photocatalyst has high activity, higher purity and excellent dispersity; the operating steps are remarkably reduced to be completed in 2-3 days and even shorter, so that more convenience and safety are realized, the reaction period is shorter and the operating parameter is easy to control.

The invention belongs to the technical field of environmental protection, and discloses a process for repairing arsenic pollution in soil by using a biological method. The process comprises the following steps: turning over, airing and smashing soil polluted by arsenic at first; controlling the grain size of the soil to be smaller than 2 mm; then spraying water; keeping the water content of the soil at 30wt%; and spreading a microbial preparation by adding 100 g of the microbial preparation in every ton of soil, turning over the soil once again three days later, and spreading the microbial preparation by adding 50 g of the microbial preparation in every ton of soil, wherein the repairing time lasts for one week. The repairing method is simple and easy to operate, low in repairing cost, environmentally friendly and pollution-free, and can be applied to large-scale soil polluted by arsenic.

The invention relates to an amidoxime modified silicon dioxide nano microsphere composite material and a preparation method thereof, belonging to the technical field of materials. The preparation method of the amidoxime modified silicon dioxide nano microsphere composite material comprises the following processes: SiO2 microspheres to SiO2-NH2 to SiO2-BR to SiO2-PAN to SiO2-PAO. Compared with thetraditional method, the method for grafting acrylic acid onto silicon dioxide has mild reaction conditions, is insensitive to the oxygen content in the system, has complete reaction, and can achieve the purpose of controlling the grafting rate by controlling the amount of acrylonitrile. The amidoxime modified silicon dioxide nano microsphere composite material prepared by the invention has more adsorption sites, high saturation adsorption capacity and high efficiency of uranium adsorption.

The invention relates to an aptamer modified triazine covalent organic framework composite material and a preparation method and application thereof. The aptamer modified triazine covalent organic framework composite material disclosed by the invention comprises a triazine covalent organic framework, gold nanoparticles and an aptamer, wherein the gold nanoparticles are supported on the triazine covalent organic framework; and the aptamer is bonded onto the surface of the gold nanoparticles. When the sequence of the aptamer is 5'-SH-(CH2)6-(ACAG4TGTG4)2-3', the composite material disclosed by the invention can be applied to enrichment of insulin in biological samples. The aptamer modified triazine covalent organic framework composite material disclosed by the invention combines the advantages of the covalent organic framework such as large specific surface area and multiple adsorbable sites and the advantage of the aptamer such as specific recognition, has excellent selectivity, and canprovide an economic, high-efficiency and high-sensitivity biological analysis method.

The invention provides a preparation method of a biochar material for efficiently removing organic pollutants in water, and belongs to the technical field of environmental pollution control engineering. The preparation method of a biochar material for efficiently removing organic pollutants in water comprises the following steps: 1, adding a certain amount of dry coconut shells into water, addinga proper amount of sodium hydroxide and urea into the aqueous solution with coconut shells, and stirring for 24 hours at room temperature; 2, curing the coconut shells treated in the step 1 in a drying oven for 24-48h, putting the solid into a quartz dry pot, putting the quartz dry pot into a tubular furnace, heating at a heating rate of 2-5 DEG C/min by taking an inert gas as a protective gas, and heating in a sectional heating manner; and 3, pouring the material calcined in the step 2 into a beaker filled with deionized water, adjusting the pH value with a hydrochloric acid aqueous solutionuntil the pH value reaches 7, carrying out suction filtration, and drying at 60 DEG C to obtain a black biochar solid.

The invention discloses a method for detecting amine harmful substances in food. The detection method comprises the following steps: (1) adding a dispersed adsorbent into a sample, uniformly performing mixing, adding an acrylamide isotope internal standard and a heterocyclic amine compound isotope internal standard, carrying out ultrasonic extraction and centrifugal separation by adopting an acetonitrile aqueous solution, taking supernate, blowing nitrogen to 0.5-1mL, and fixing the volume by using an ammonium acetate solution containing acetic acid to obtain a purified solution; (2), adding ferroferric oxide nanoparticles into the purified liquid, carrying out vortex oscillation decolorization and centrifugation, and taking supernatant as to-be-detected liquid; and (3), detecting the amine harmful substances in the to-be-detected liquid by using an ultra-high performance liquid chromatography-tandem mass spectrometry method. The method has the advantages of excellent purification effect, high sensitivity and strong specificity, and is suitable for simultaneous determination of a plurality of amine harmful substances in food.

The invention discloses a method for treating heavy metal waste liquid by using modified walnut shell biochar, which belongs to the technical field of heavy metal pollution control. In order to improve the efficiency for treating the heavy metal waste liquid by biochar, the present invention provides the method for treating the heavy metal waste liquid by using the modified walnut shell biochar. The method comprises the following steps: the walnut shell powder is subjected to high-temperature vacuum heating, and then ultrasonically cleaned to obtain the walnut shell biochar; the walnut shell biochar and a sodium citrate solution are mixed to obtain the modified walnut shell biochar; and the modified walnut shell biochar and the heavy metal waste liquid are reacted. The method adopts a composite modification method, through low-frequency ultrasonication and the sodium citrate modification treatment, the walnut shell biochar has more adsorption sites and enhance the adsorption performance of the walnut shell biochar, and the method processes the heavy metal environment pollution at low cost and high efficiency while recycling the agriculture and forestry wastes.

The invention discloses a sulfur-doped nano ferroferric oxide/biochar composite material, a preparation method thereof and application thereof in remediation of heavy metal arsenic and/or lead contaminated soil. The composite material is prepared by loading sulfur-doped nano ferroferric oxide on a biochar carrier, and biomass raw materials used for preparing the biochar carrier comprise agricultural waste. In the preparation process of the sulfur-doped nano ferroferric oxide/biochar composite material, solid loading and vulcanization modification are combined at the same time, so that the composite material has an efficient adsorption performance, reduction performance and recovery potential, and the purpose of efficiently removing arsenic and lead pollutants in soil at the same time can be achieved. According to the method, the limitation of solely using biochar or a nano-iron material is broken, the problem that arsenic existing in an anionic form and lead existing in a cationic formare difficult to remove efficiently at the same time in the actual soil remediation process is solved, and the composite material has wide application prospects.