82 results about "Cadmium Compound" patented technology

The invention discloses a preparation method of a cysteine surface modified CdTe or CdTe / CdS quantum dot, which comprises the following steps of: under the condition of room temperature, mixing a cadmium-containing compound powder with cysteine, fully stirring and regulating the pH value to obtain a Cd precursor solution; then adding NaBH4 in Te powder, injecting an acid liquor, bringing H2Te gas generated by acidization under the action of a nitrogen flow out and introducing into the Cd precursor solution, heating for reaction and refluxing to obtain a CdTe quantum dot solution, adding Na2S solution in the CdTe quantum dot solution, and standing to obtain the cysteine surface modified CdTe / CdS nuclear shell quantum dot. The quantum dot disclosed by the invention is added in an arsenic ion-containing solution, and is subjected to fluorescent quantitative characterization by using a fluorospectro photometer to obtain a fluorescent response curve, and therefore, the qualitative or quantitative detection of the concentration of trivalent arsenic ions in a solution to be detected can be realized. The preparation method has the advantages of simpleness in operation, high sensitivity, good selectivity and the like.

The invention discloses a lead-cadmium compound conditioner for rice field soil as well as preparation and application methods of the lead-cadmium compound conditioner. The conditioner is composed of the raw materials in mass fractions: 30-50% of calcium carbonate, 5-10% of hydroxyapatite, 20-30% of sepiolite and 20-30% of zeolite; the preparation of the conditioner comprises the following steps of: weighing various raw materials according to the mass fractions of the components of the lead-cadmium compound conditioner; continuously stirring the various raw materials in a stirring device for at least 30 min, and thoroughly stirring and evenly mixing all the materials; and the method of application of the conditioner comprises the following steps of: (1) analyzing the total quantity of lead and cadmium in the rice field and the content of lead and cadmium in exchange state; (2) determining the pollution level of the rice field soil by using an evaluation model; (3) applying the lead-cadmium compound conditioner according to the lead-cadmium pollution level in the rice field, and applying the lead-cadmium compound conditioner to the slightly polluted rice field at 100-150 kg / mu, to the mildly polluted rice field by 150-300 kg / mu and to medium-polluted rice field at 300-600 kg / mu, and balancing and stabilizing for 10-15 days; and (4) analyzing and measuring the content of lead and cadmium in exchange state in the rice field, and if the fixed rate is lower than 90%, additionally applying the conditioner at 100-150 kg / mu.

Provided are a photocatalyst which is high in catalytic activity, is nontoxic, has a long life, allows visible light to be used directly for its photocatalytic reaction and is especially useful for hydrogen generation, and a process for producing it. It contains a cadmium compound, has a capsular structure, has an average particle diameter of 100 nm or less and can be manufactured by dropping a solution of a cadmium salt into a solution of a sodium compound or admixing a solution of a sodium compound in a suspension of particles of a cadmium compound.