2 results about "Soil lead" patented technology

The application discloses an L-cysteine-based soil lead pollution leaching agent and a preparation method thereof, and belongs to the technical field of soil heavy metal pollution remediation. The L-cysteine-based soil lead pollution leaching agent comprises the following raw materials: an L-cysteine solution, a pH buffer and a polyvinylpyrrolidone solution; the concentration of the L-cysteine solution is 0.3-0.5 mmol / L, the concentration of the pH buffer is 1 mmol / L, and the mass fraction of the polyvinylpyrrolidone solution is 0.003%-0.005%; the volume ratio of the L-cysteine solution, the pH buffer and the polyvinylpyrrolidone solution is 1:1:0.15-0.4. The leaching agent has a remarkable leaching effect on soil lead, and the removal rate of the leaching agent on the contaminated soil with a Pb content of more than 500 mg / kg can reach more than 85%, so that the leaching agent can effectively prevent lead from migrating through the soil into a food chain or a water environment, and is much stronger than a traditional carboxyl-based leaching agent.

This invention discloses a rapid detection method and system for lead in soil based on quantum dot fluorescence, specifically relating to the fields of optical detection and fluorescence analysis. It addresses the problem of fluorescence signal distortion caused by non-specific heterogeneous aggregation of nanoparticles in the extract solution when existing quantum dot fluorescent probes detect lead in soil. The method acquires the fluorescence spectrum of the mixed system and separates the characteristic fluorescence peaks of the quantum dots. It performs time-resolved measurements of the fluorescence signal, divides the time window of the fluorescence lifetime decay curve according to a preset time threshold, and calculates the integral area. Simultaneously, it analyzes the quenching kinetics of the characteristic fluorescence peak intensity to obtain the fluorescence quenching rate constant, and calculates the lifetime distribution characteristic ratio based on the integral area of ​​the time window. It determines the contribution ratio of non-specific aggregation to the fluorescence quenching rate constant through cooperative deviation analysis. Based on this ratio, it compensates and corrects the intensity of the characteristic fluorescence peak, accurately calculating the lead ion concentration in the soil extract solution.