892 results about "Cadmium ion" patented technology

The invention discloses a carbon-based composite material for arsenic and cadmium polluted soil remediation and application of the composite material. The carbon-based composite material disclosed by the invention is prepared by the steps: taking crop straws as raw materials, and charring to prepare charcoal; mixing with an iron salt solution according to a certain solid-liquid ratio, regulating the pH value of the solution in the process so as to realize coprecipitation of the two materials; performing pyrolysis, thereby obtaining the carbon-based composite material. The carbon-based composite material prepared in the invention is applied to arsenic and cadmium compound polluted soil, and methods such as turning over, watering and the like are combined, so that the content of arsenic and cadmium in an effective state can be obviously reduced; therefore, the arsenic and cadmium in the soil can be transferred to a direction with low biotoxicity and migration, the physicochemical properties of the soil can be improved to a certain degree, and the composite material is suitable to be applied to multiple types of soil. The arsenic and cadmium ions in a water body can be effectively removed, the preparation process is simple in operating steps, and the material is wide in source, low in production cost and environment-friendly.

The invention discloses a modified magnetic biochar adsorbing material and application thereof. The adsorbing material is prepared through the following steps: taking agricultural waste corn stalks as a raw material, magnetizing and carbonizing the raw material, and adhering chitosan coating to the surface of the raw material. The adsorbing material is wide in raw material source, stable in structure, low in possibility of blocking, high in efficiency of effectively removing typical heavy metal pollutants namely cadmium ions and copper ions in water, convenient to separate, recycle and reuse and free of secondary pollution, achieves resource utilization, and has good environmental benefits and economic benefits.

The invention discloses an application of melatonin in reducing cadmium accumulation in plants. The application includes the following steps: (1) mixing melatonin and additives to form aqueous solution; (2) spraying the aqueous solution on plant leaf surfaces under cadmium stress or filling the aqueous solution in nutrient solution or soil where plants grow. The melatonin can quickly and efficiently reduce cadmium content in plant leaves, change distribution of cadmium ions in plant cells, and relieve damage of cadmium to cells; in addition, the melatonin is simple to prepare and convenient to use, does not cause product and environment pollution, does not generate phytotoxicity easily and has a wide application prospect.

The invention relates pseudomonas, use thereof and a method for removing cadmium pollution to the environment. The pseudomonas class is named pseudomonas putidaHN103 and the collection number in a collection center is CCTCCNo.M2011184; and the shape and characteristics of the pseudomonas putidaHN103 comprise: 1) on a culture medium, a bacterial colony which used to be colorless and transparent turns white, smooth and convex-like with irregular edges; and 2) according to the result of bacterial microscopic examination, pseudomonas belongs to brevibacterium and is gram negative. The use of the bacteria is the use of the bacteria as a biological repair material for removing cadmium pollution. The method for removing cadmium pollution to the environment comprises the following steps: 1) regulating the cadmium ion concentration in sewage to a range in which pseudomonas can grow normally; 2) placing pseudomonas; 3) keeping the pseudomonas in the sewage for a certain time period; and 4) removing bacterial absorbing cadmium ions. The pseudomonas requires small investment, is low in cost, high in adaptability and capable of effectively removing cadmium, can quickly and obviously lower the concentration of cadmium ions in the environment and is suitable for biological remediation environments polluted by cadmium.

The invention relates to an electrochemical sensor for simultaneously detecting cadmium and lead ions and a preparation method. The sensor is composed of an electrochemical work station, a working electrode, a counter electrode, a reference electrode and an electrolytic tank, wherein the working electrode adopts a glassy carbon electrode as a base, and a Nafion / N-doped micropore carbon composite membrane is modified on the surface of the working electrode; the electrochemical sensor can realize the simultaneous detection of the trace cadmium and lead ions, and the detection limits are respectively 1.5mug / L and 0.05 mug / L. The preparation method of the working electrode provided by the invention has the advantages that simplicity and environmental protection are realized, the working electrode combines the characteristic that hetero atoms and Nafion can effectively adsorb heavy metal ions, and bismuth and to-be-detected heavy metal can form an alloy, and the sensitivity of sensing heavy metal ions of the glassy carbon electrode is remarkably improved. The electrochemical sensor provided by the invention has the advantages that the reproducibility is good, the antijamming capability is strong, the detection limits are low, and the electrochemical sensor is applied in on-site analysis of cadmium and lead ions.

The invention relates to a method for detection Listeria monocytogenes with loop-mediated isothermal amplification-CdS nanoparticles labeling electrochemistry. The method is characterized in that the method comprises the following steps of: obtaining double-stranded target sequence of amplification reagent-Listeria monocytogenes to be detected by means of loop-mediated isothermal amplification reaction; pyrolyzing a double-stranded target sequence in water bath into a single-stranded target sequence, then self assembling and fixing at the surface of gold electrode, so that the target sequence modified electrode of the Listeria monocytogenes to be detected is obtained; afterwards, labeling the probe sequence coming from the Listeria monocytogenes by CdS nanoparticles to obtain a labeled probe sequence; carrying out molecular hybridization on the labeled probe sequence and the target sequence of the target sequence modified electrode, and carrying out electrochemical detection by simultaneity plating Hg anodic stripping method; detecting out cadmium ions corresponding to the species-specific genes (actA) of the detected Listeria monocytogenes. The method has the advantages of speediness, strong specificity, high sensitivity and convenient use.

The invention discloses a carbon quantum dot / aurum cluster ratiometric fluorescent probe for detection of cadmium ion and ascorbic acid. A preparation method comprises the following steps: preparing CQDs (Carbon Quantum Dots) from alanine and histidine through a one-step hydrothermal method; performing amino-functionalization on the CQDs by using 3-aminopropyltriethoxysilane, wherein the CQDs which are subjected to the amino-functionalization serve as a reference chromophore; reducing chloroauric acid through sodium borohydride by taking 11-sulfydryl undecanoic acid as a surfactant to obtain MUA-modified AuNCs (Aurum Nano Clusters), wherein the MUA-modified AuNCs serve as a main fluorophore of the ratiometric fluorescent probe; finally, coupling the CQDs and the AuNCs through an amidation reaction to obtain the CQDs / AuNCs ratiometric fluorescent probe. On the basis of static quenching and inter-filtering effects, the fluorescence of the CQDs / AuNCs can be quenched by Cd<2+>; the invention discloses the application of the CQDs / AuNCs ratiometric fluorescent probe in Cd<2+> detection. The fluorescence of the CQDs / AuNCs which is quenched by the Cd<2+> can be recovered by the ascorbic acid, so that the ratiometric fluorescent probe can also be used for the detection of AA (Ascorbic Acid). The ratiometric fluorescent probe disclosed by the invention has the lower detection limit of 32.5 nM to the Cd<2+>, has the lower detection limit of 0.105 muM to the AA, and has an application value in the detection of the cadmium ion and the ascorbic acid.

The invention discloses test paper for rapidly detecting the immunochromatography of cadmium ion colloidal gold and a preparation method and application thereof. The test paper consists of a sample pad, a colloidal gold combination pad, a nitrocellulose membrane, absorbent paper and a plastic base plate; The sample pad, the colloidal gold combination pad, the nitrocellulose membrane and the absorbent paper are sequentially stuck on the plastic base plate; an anti-cadmium ion monoclonal colloidal gold label is coated on the colloidal gold combination pad; a goat anti-rat IgG antibody and a complete antigen Cd-iEDTA-BSA of heavy metal cadmium are sequentially coated on the nitrocellulose membrane; the goat anti-rat IgG antibody is used as a quality control line; and the complete antigen Cd-iEDTA-BSA of the heavy metal cadmium is used as a test line. The test paper detects residual metal cadmium in ambient soil, a water body and an aquatic product based on the immunology theory of antigen antibody; and compared with the prior detection system, the test paper has the advantages of rapidness, cheapness, convenience, sensitivity and speciality, can give a result within five minutes and is convenient to carry along to carry out field monitoring.

The invention relates to a preparation method of a magnetic cadmium ion surface imprinted polymer, which comprises the following steps: synthesizing magnetic Fe3O4@SiO2 microspheres through a coprecipitation method and a sol-gel method, and treating with acid to increase the surface hydroxyl content; introducing polymerizable double bonds onto the surfaces of the Fe3O4@SiO2 microspheres through a two-step method, namely grafting amino groups onto the surfaces of the microspheres by using aminosilane coupling agent, and generating the double bonds through reaction between acid anhydride and the amino groups; and finally, performing polymerization reaction by taking the Fe3O4@SiO2 microspheres as carriers, taking Cd(II) as a template, taking ethylene glycol dimethacrylate as crosslinking agent and taking methacrylic acid and salicylaldoxime as monomers, and washing off the template Cd(II) after the reaction, thus obtaining a polymer layer with a large number of Cd(II) imprinted holes distributed on the surfaces of the Fe3O4@SiO2 microspheres. The magnetic cadmium ion surface imprinted polymer provided by the invention can be used for separation and removal of cadmium ions.

The invention discloses a method for preparing a metal ion adsorbent, and relates to a method for preparing resin with adsorption function on metal ions. The method uses beta-cyclodextrine as a raw material, and uses acrylic acid and acrylamide as copolymerization reactants. The method comprises the following steps of: adding alkali solution of the beta-cyclodextrine and cyclohexane into a reactor, heating the reactor in a water bath and introducing nitrogen into the reactor, and stirring the mixture; and then dropwise adding uniformly stirred solution of initiator, cross linker, acrylic acid and acrylamide into the reactor to perform polymerization reaction, and obtaining the resin with performance of adsorbing the metal ions by heat preservation, cooling, filtering and vacuum drying. The resin prepared by the method has good adsorption effect on heavy metal ions such as copper ions, lead ions, cadmium ions and the like, the metal ion adsorbing capacity of 80 mg / L Cu2+ solution is 107.37 mg / g, the metal ion adsorbing capacity of 80 mg / L Pb2+ solution is 80.04 mg / g, the metal ion adsorbing capacity of 80 mg / L Cd2+ solution is 78,94 mg / g, and the resin can be made into a heavy metal ion wastewater treating agent and has good application prospect in the aspects of removing and reclaiming heavy metal ions.

The invention discloses a metal-organic frame material for absorbing and storing acetylene and a preparation method thereof. The metal-organic frame material adopts a three-dimensional network structure which is formed by transition metal ions and multitooth organic ligands 5,5'-(pyridine-2,5-dibase)-isophthalic acid through coordinate bonds or intermolecular forces. Bivalent copper, zinc, cobalt, nickel and cadmium ions are preferably selected as the transition metal ions. The metal-organic frame material has a simple preparation process and has higher specific surface area being 2000-2200m2 / g and pore volume being 1.0-1.3cm<3> / g. The multitooth organic ligands used by the material introduce an alkaline unit containing pyridine, so that the absorption and storage capacity of acetylene can be effectively increased. The materials has a higher acetylene absorption capacity under the 273-298K temperature condition, can be used under lower pressure, and can be used as a novel efficient acetylene absorption and storage material.

The invention discloses a fluorescent probe: a benzothiazole-terpyridine compound used for distinguishing and detecting zinc ions and cadmium ions. The probe has a structural formula as shown in (I). The compound is prepared by using bromobenzaldehyde and O-aminothiophenol as raw materials, and performing a dehydration cyclization reaction, a coupling reaction and a terpyridine derivative reaction. According to the invention, the raw materials are cheap and easily available, a synthesis route is simple, a yield is relatively high, and the fluorescent probe is high in fluorescence quantum efficiency, and relatively high in heat stability and dissolvability. The probe uses a photoinduced charge transfer mechanism, has different luminescence response for the zinc ions and the cadmium ions, has characteristics of rapid response, high sensitivity and high selectivity, is suitable for food safety inspection, laboratory safety inspection, and especially industrial wastewater monitoring, and has a wide application prospect in environment monitoring, ecological protection, disease diagnosis, industrial production and sewage inspection.

The invention discloses a quantum dot-organic dye compound closed / open type cadmium ion ratio fluorescent probe and a preparation method thereof. The preparation method comprises selecting CdTeQDs to serve as a main fluorescence source, introducing fluorescein isothiocyanate (FITC) to serve as an auxiliary (or reference) chromophore, and forming a CdTe-FITC compound dual-emitting probe in a hydrogen bonding mode. The problem that fluorescence signals of a traditional single-fluorescence probe are difficult to obtain accurately is solved. A fluorescence closed / open model is adopted, disturbance of factors except an analyte on a fluorescence enhancement reaction can be effectively reduced, the fluorescence enhancement reaction has specificity, and accordingly sensitivity and selectivity of analyte detection are improved. The preparation method is simple and low in cost, and the prepared product can perform accurate, sensitive, simple, convenient and rapid detection on Cd2+ in complex systems and biological samples, has important reference values for developing high-quality fluorescence probes of other types and provides a new developing direction for research in the fields of biological detection and chemical analysis and the like.

The invention relates to a method for removing heavy metal cadmium from rice by utilizing complex lactobacillus fermentation. The method comprises the following steps: crushing a rice sample with the content of cadmium of more than 0.2mg / kg, sieving, and adding deionized water; inoculating a mixed zymocyte suspension containing a lactobacillus plantarum seed culture solution and a pediococcus pentosaceus seed culture solution, standing, fermenting at a constant temperature, washing fermented rice flour with water, and centrifugally dewatering to remove free heavy metal cadmium ions in the rice; and finally, drying centrifuged rice flour wet residues. By adopting the method provided by the invention, the removal rate of the cadmium in the rice is up to 70% above; the dewatered rice flour can be used as a feed or used for producing fermented rice flour after being dried by hot air. The content of the heavy metal cadmium in the rice can be effectively reduced, and the utilization problem of the rice with the excessive cadmium is effectively solved.

The invention relates to a cadmium ion fluorescence probe and a preparation method thereof. The cadmium ion fluorescence probe consists of a derivative of quinoline with a position 2 which is modified by aza-crown ether. An aza-crown ether group is bonded onto a quinoline chromophoric group with an auxiliary coordination function to synthesize the cadmium ion fluorescence probe with a specific response function. As homologous transition metal ions, the interaction of cadmium and zinc with S, O and N donors is very close. Comparatively, the connection of the cadmium with the S and N donors is closer than the connection of the zinc with the S and N donors. The novel fluorescence probe is designed by using the characteristics. The influence of zinc ions on the unique response of the cadmium ion fluorescence probe is overcome. The fluorescence probe can be used for the selective rapid fluorescence detection of the cadmium ions in water bodies, the selectivity is very good, the resistance to interference of other metal ions is strong and the cadmium ion fluorescence probe consists of ideal sensing molecules for the field detection of the cadmium ions.

A F-B dyestuff fluorescent probe used for detecting Cb ion in cell is featured as enabling said probe to detect Cb ion concentration in micromole grade, increasing fluorescent quantum output rate by four tines after probe molecule is complexed with Cb ion, moving emission spectrum blue shift to be about 40-80nm before and after Cb ion is complexed so that said probe can be used to carry out ratio fluorescent detection of Cb ion.

The invention relates to a process for preparing high-performance conducting fiber, which comprises first, preprocessing, washing out foreign matters on the surface of fiber, second, coursing, adopting coursing agent to immerse fiber, and to improve the surface structure of the fiber, leading the surface to be roughness which is beneficial for absorbing metallic ion, third, sensitizing, utilizing stannous chloride or cadmium chloride solution to immerse fiber, leading the surface of fiber to absorb a layer of tin ions and cadmium ions, thereby forming a layer of metal catalytic layer, fourth, chemically coating silver, fifth, solidifying, utilizing oxalic acid solution to immerse, and getting end products after drying. The invention is simple and is easy to be operated, compared with the traditional electric plating, conducting fiber which is prepared by the invention has excellent electrical conductivity property, specific surface area specific resistance reaches 2-10 Ohm, and the characters of the original fibers are kept, the hand feeling is soft, and the invention can be applied in various commingled yarn fabrics.

The invention discloses a ratio-type variant receptor mercury ion fluorescent probe and its preparation method and use. The ratio-type variant receptor mercury ion fluorescent probe has the advantages of simple synthesis processes, good light stability, the largest emission wavelength of 550nm and good chemical stability under neutral conditions. Through amide functional group tautomerism, the receptor has a deformation capability of combination of an imidic acid isomer and mercury ions and combination of an amide isomer structure and other metal ions so that the receptor has mercury ion specific combination selectivity. The probe with the mercury ion produces fluorescence spectrum red shift to 633nm and the fluorescence spectrum is enhanced by 9 times. After bonding to other metal ions especially such as congener zinc ion and cadmium ions, the probe has no obvious fluorescence change and has mercury ion specific fluorescence signal selectivity. The probe realizes mercury ion specific ratio identification, can be used in detection of mercury ions in cells and has a wide application prospect in detection of mercury ions in other organisms and environments.

A process for preparing the cadmium sulfide nanorods includes proportionally adding mercaptoacetic acid to the solution containing cadmium ions, stirring, proportionally adding sodium sulfide, reaction at 100-500 deg.C for 1-200 hr, centrifugal treating, and drying. Its advantage is no environmental pollution.

The invention aims at providing an electrochemical sensor for sensitively detecting heavy metal cadmium ions and a preparation method of the electrochemical sensor. The structure of the sensor is formed by an electrochemical workstation, an electrolytic cell and electrodes; the electrodes include a platinum wire counter electrode, a silver / silver chloride reference electrode and a working electrode, wherein the working electrode refers to a glassy carbon electrode adopting nitrogen-sulfur codoping and graphite porous carbon / Nafion / bismuth film modification. The electrochemical sensor can realize sensitive detection of trace heavy metal cadmium ions, the detection linear range is 4-80 micrograms / L, and the detection limit reaches 0.1 microgram / L. By combining with good properties of a bismuth film, a Nafion film and a nitrogen-sulfur codoped porous carbon material, the electrochemical sensor has the performances of high sensitivity, good selectivity, wide linear range, good reproducibility, good stability and the like and can be applied to detecting the heavy metal cadmium ions in an actual water sample.

The invention relates to a method for rapidly preparing a water-soluble quantum dot by an ultrasonic spraying method with continuous production, which comprises the following steps that: cadmium ions or zinc ions and hydrogen (or selenide) telluride or sodium hydrogen telluride (or selenide) react to obtain a precursor solution of cadmium (zinc) telluride (selenide) through the complexation of a mercapto compound. An ultrasonic atomizer is used to atomize the precursor solution to form fogdrops of the precursor solution, and the fogdrops flow through a device with constant temperature to react to obtain the water-soluble quantum dot. The method has the advantages of high speed and continuous quantum dot production, the prepared quantum dot has high fluorescence quantum yield (between 20 and 50 percent), and good monochromaticity of luminescence (the peak width at half height of a fluorescence spectrum within the range of visible light is between 30 and 40nm), and the size of nano-particles can be easily controlled by changing the temperature and flow rate, thereby realizing the adjustment to luminescence peak positions (between 400 and 700nm).

The invention discloses magnetic composite hydroxyapatite nanoparticles. The magnetic composite hydroxyapatite nanoparticles are composed of Fe3O4 nanoparticles and hydroxyapatite nanoparticles, wherein the molar ratio of the Fe3O4 to the hydroxyapatite is (1-10): 1; the magnetic composite hydroxyapatite nanoparticles are spherical aggregate or agglomerate in which the Fe3O4 nanoparticles and the hydroxyapatite nanoparticles are distributed evenly and alternately. The preparation method of the magnetic composite hydroxyapatite nanoparticles is simple; the nanoparticles are capable of efficiently removing heavy metal ions in sewage, and in the later treatment period, quick magnetic separation can be realized; the nanoparticles have the adsorbing capacity of 440mg / g to lead ions, the adsorbing capacity of 238mg / g to cadmium ions, the adsorbing capacity of 139mg / g to zinc ions and the adsorbing capacity of 135mg / g to copper ions in the sewage; the magnetic composite hydroxyapatite nanoparticles have a rapid magnetic response characteristic, and are capable of realizing rapid solid-liquid separation with an external magnetic field, and the separation process is high in separation efficiency, and simple and efficient to operate; and besides, the nanoparticles are not residual in water and do not cause secondary pollution to the water and the environment.

The invention discloses a preparation method of straw anaerobic fermentation residue active carbon for processing cadmium-containing waste water, which comprises the following steps: cleaning, cutting, drying, crushing, and sieving straw anaerobic fermentation residues, soaking the residues with a potassium hydroxide solution with a mass fraction of 5-20% at a vibration rotating speed of 100-120 r / min for 3-12 hours, wherein the mass ratio of the potassium hydroxide to the straw anaerobic fermentation residue powder is 0.5-4:1, drying, performing activation in a muffle furnace for 30-60 min at a temperature of 400-550 DEG C, washing with hot distilled water at 70-80 DEG C to obtain a pH of 5-6, drying the obtained product, grinding the product to obtain a particle mesh size of less than 150 meshes. The active carbon prepared in the invention has good processing effect on cadmium-containing waste water, has a theoretical saturated adsorption capacity of cadmium ions of 20.79-66.22 mg / g which is far higher than that of common commercial active carbon. The process of the invention is simple and practical, low in cost, less in pollution, and good in adsorption effect on metal ions, and thus has good application prospects.

The invention relates to amphiphilic macromolecular modified oil-soluble nuclear / shell quantum dots and a preparation method. A nuclear layer is of CdSe quantum dots; and a shell layer comprises CdS, an alloy layer, ZnS, an amphiphilic polymer layer from the inside to the outside in turn. The structure of the alloy layer is: Cd0.4Zn0.6S, Cd0.45Zn0.55S or Cd0.6Zn0.4S; the structure of the amphiphilic polymer layer is that: an inner layer is an alkyl chain hydrophobic layer; a connecting layer is aliphatic long carbon chains; and an outer layer is a carboxyl hydrophilic layer; and the particle size range of the quantum dots is between 200 and 1,000 nm. By covering different shell layers with appropriate thickness on the surface of the CdSe nuclear quantum dots, the nuclear / shell quantum dots with high fluorescence efficiency and stable fluorescent properties are synthesized; by performing self-assembly water-solubility modification on self-made amphiphilic polymer and amphiphilic polymer, a formed amphiphilic polymer layer protects the surface structure and fluorescence properties of the nuclear quantum dots, can restrain cadmium ions and selenium ions from diffusing outwards and reduces the toxicity of the quantum dots to organisms; and the modified quantum dots cannot generate fluorescence resonance energy transfer in multi-flux detection.

The invention relates to a fluorescent ion probe reagent used in cadmium ion detection, which is the derivate of 8-hydroxyquinoline and triazolyl modified Beta-cyclodextrin; wherein 8-hydroxyquinoline is adopted as probe molecule, and nitrogen oxide atom in quinoline ring and nitrogen atom in triazole ring are taken as the bonding lotus of cadmium (II) ion. The method comprises the steps of: synthesizing 8-hydroxyquinoline alkynyl intermediate by 8-hydroxyquinoline, 3-propargyl bromide and the like firstly; and synthesizing a target product by the intermediate, mono-6-deoxy-6-azido-Beta-cyclodextrin, sodium ascorbate and the like. The invention has the advantages that as water-soluble cadmium ion fluorescent probe, the prepared cyclodextrin derivate has simple synthesizing process and high yield, and is suitable for further enlargement synthesis and practical production application; the sensing operation to cadmium ion is simple and practical; and the sensitivity is high and displayed by fluorescence spectrum. As cadmium ion fluorescent probe, the invention exactly explains the coordinate bonding mechanism to cadmium (II) ion and has wide application prospect.

The invention provides a foliar blocking and controlling agent capable of reducing cadmium contamination of brown rice, and a preparation method and application thereof, belonging to the technical field of foliar sprinkling fertilizer for crops. The preparation method comprises the following steps: adding, on the basis of each liter of water, 200 to 230 g of silicon dioxide, 60 to 80 g of potassium oxide, 8 to 15 g of calcium oxide, 1 to 2 g of selenium, less than 2 g of adding elements and 1 to 2 g of a plant growth regulator into a container equipped with a stirring device; carrying out uniform mixing under stirring; controlling stirring time and speed; and the discharging the obtained mixture and carrying out so as to obtain the foliar blocking and controlling agent capable of reducing cadmium contamination of brown rice. The application of the foliar blocking and controlling agent comprises a first step of diluting the foliar blocking and controlling agent with water and a second step of sprinkling the diluted agent on the leaves of rice in stages. The foliar blocking and controlling agent inhibits migration of cadmium ions, guarantees ideal cadmium reduction effect on brown rice, realizes the dual effects of cadmium blocking and nutrient absorption of plants, enables the yield of paddy rice per mu to increase by 6% or above, is beneficial for prolongation of the life span of human beings and increases the added value of rice; the preparation method is simple and has no strict requirements on essential factors; and the application method is convenient and efficient.

The present invention discloses a repairing chemical agent for reducing cadmium contamination of crops and a using method. The repairing chemical agent comprises the following raw materials: 5-45 parts by weight of a natural surfactant, 4-15 parts by weight of an oxidant and 10-60 parts by weight of a silicate mineral material. On one hand, the repairing chemical agent disclosed by the present invention, through irrigation and other farming activities, can be adsorbed on the surfaces of soil particles, so that a property of a solid-liquid interface is changed, the adhesion between cadmium ions in soil and the soil is weakened, the separation of heavy metal ions from the soil is promoted, the heavy metal ions generate a complex with active materials, and thus, the absorption of heavy metals by the crops is reduced. On the other hand, the repairing chemical agent reacts with unstable cadmium in the heavy metal contaminated soil, and stable insoluble cadmium salt precipitation is generated, so that the cadmium content in the planted crops is significantly reduced, and the requirements on the quality of safe agricultural products are met.

The invention relates to a production method for lowering cadmium content in a Sauropus androgynus product. After soil is leveled and is in deep ploughing, the pH value of the soil is determined and then adjusted; after a ridge is ploughed, base fertilizer is applied; Sauropus androgynus is planted after covering surface soil and is irrigated and watered at regular time; when tender tips grow on the plant, a tender tip of which the length is 12 cm is picked to obtain the Sauropus androgynus product with low cadmium content; the base fertilizer is formed by mixing fermented high-protein organic fertilizer, superphosphate and ant ash or by mixing fermented high-protein organic fertilizer, superphosphate and lemery salt. The invention has simple operation method, effectively fixes cadmium ions in soil by regulating the pH value of soil and applying high-protein organic fertilizer, reduces the possibility that the root of the Sauropus androgynus adsorbs cadmium ions from oil so as to effectively control cadmium content in the Sauropus androgynus while ensuring yield. The produced Sauropus androgynus product has stable and safe quality, can be applied on small-area or large-scale production cultivation and has strong operability.

The invention provides a preparation method of a new adsorbent, the method uses a dendritic polymer to modify a graphene oxide adsorption material, and the graphene oxide adsorption material modified by the dendritic polymer can effectively adsorb lead ions, cadmium ions, manganese ions, copper ions and other heavy metal ions in wastewater. The method is as follows: first using graphite powder as a raw material to prepare multilayer graphene oxide by concentrated sulfuric acid, potassium permanganate and hydrogen peroxide oxidation, fully dissolving the graphene oxide in ethanol with the aid of ultrasonic, then adding a certain amount of the dendritic polymer for water bath reaction at 30-80 DEG C for 6 to 48 hours, performing vacuum suction filtration of an obtained product, then washing with the ethanol, and then drying at 50-100 DEG C to obtain a heavy metal adsorption material. SEM (scanning electron microscope) pictures show that the adsorbent has a loose structure, and the adsorbent has a good application prospect in heavy metal adsorption field. Adsorption experiments show that, under the condition of normal temperature, the adsorbent has a good adsorption capacity to the lead ions, cadmium ions, manganese ions and copper ions, and especially has a strong adsorption capacity to the lead ions, and the maximum adsorption amount can reach 300mg / g above.

The invention discloses a synchronous-pyrolysis iron loaded biochar preparation method which comprises the following steps: S1, preparing a biomass raw material, cleaning the biomass raw material andsmashing and sieving to obtain biomass powder; S2, soaking the biomass into an iron containing solution; S3, evenly mixing the biomass powder with the iron containing solution and filtering to achievesolid-liquid separation; S4, pyrolyzing the filtered biomass powder under the anaerobic condition, wherein a pyrolysis temperature is 500 to 700 DEG C, and thermal-insulation time is 1 to 3 hours; S5, smashing and sieving the pyrolyzed biomass powder to obtain the iron loaded biochar. The biochar prepared from the raw material of phyllostachys viridis can be applied to a heavy metal cadmium ion removing process in a water environment, so that the problems that an existing adsorption technology has a poor adsorption effect and secondary pollution in a heavy metal adsorption process are solved;meanwhile, a biochar carbonizing process can seal carbonic acid in biochar, emission of greenhouse gas of carbon dioxide is reduced, and an environmental ecological effect is beneficiated.