10 results about "Arsenite" patented technology

The invention provides a method for removing arsenic in water through sacrificial iron anode electrocoagulation, and belongs to the technical field of feed water treatment. According to the method for removing arsenic in water through sacrificial iron anode electrocoagulation, arsenic-containing underground water is electrolyzed through electrocoagulation treatment, an iron sheet serves as an anode in the electrocoagulation treatment, a sodium sulfate solution serves as electrolyte, and arsenic in water is removed after electrolysis is finished. The current of the electrocoagulation treatment is 5-10 mA, the treatment time is 8-15 min, and the concentration of the sodium sulfate solution is 5-20 mM. According to the invention, an electric coagulation technology is adopted, ferrous iron is generated by electrolysis of an iron anode to promote oxidation of arsenite and adsorption of arsenic on iron precipitates, so that the purpose of separating arsenic from water is achieved, and the method has the advantages of high treatment efficiency, environmental friendliness, flexibility, controllability and the like.

The invention discloses an arsenic microbial sensor based on tolerance bacteria domestication and a preparation method thereof, and belongs to the technical field of genetic engineering. Arsenite (As < 3 + >) tolerant bacteria are obtained through laboratory domestication, and the arsR promoter key mutation site (-30Ggt; t and / or-54 Tgt; and C) constructing a fluorescent reporter plasmid containing a mutation promoter and a reporter gene egfp, and obtaining the arsenic microbiological sensor based on the fluorescent reporter plasmid. The detection limit of the sensor to arsenic is as low as 0.28 mu M, the sensitivity is obviously superior to that of a wild type, and the specificity is high. The invention also provides a preparation method of the arsenic microbiological sensor and a method for detecting arsenic concentration, and the arsenic microbiological sensor has the advantages of low cost and simplicity and convenience in operation.

This invention provides a device to enable thermally intensified interfacial polymerization for facile fabrication of ultra-selective reverse osmosis (RO) membranes for various water treatment scenarios including seawater desalination and water reuse. The device pre-heated the organic solvent and then performed interfacial polymerization between the room-temperature aqueous phase and the heated organic phase. The fabricated RO membranes demonstrated excellent selectivity towards toxic micropollutants (i.e., boron in seawater, arsenite in groundwater, and organic micropollutants in wastewater) and high water-permeability. This invention offers a facile, cost-efficient and highly effective alternative for water treatment.

This invention discloses a promoter specifically expressed in leaf veins, its expression vector, and its applications. Belonging to the fields of genetic engineering and biotechnology, this invention uses thermal asymmetric PCR and chromosome walking technology to clone a full-length 1772 bp promoter sequence from *Pteris vittata*. This promoter replaces the CaMV35S promoter on the vector pCAMBIA1381Z, thereby driving the expression of the downstream GUS reporter gene. The recombinant plant expression vector containing this specific expression promoter is transformed into tobacco to verify its function, confirming that this promoter can drive the GUS gene in tobacco leaves. This invention utilizes this promoter to construct a plant expression vector driving the expression of the *Pteris vittata* arsenite reverse transport protein PvACR3. Transforming this vector into tobacco confirms that this specific promoter driving PvACR3 expression can specifically increase the arsenic content in tobacco leaves. The promoter of this invention can be used to cultivate transgenic arsenic-accumulating engineered plants, promoting the development of phytoremediation technology.

This invention provides a standard quality control sample for edible fungi matrix containing multiple arsenic forms, its preparation method, and its application, relating to the field of standard material technology. The invention involves preparing a powder from dried edible fungi samples (containing monomethylarsenic acid, dimethylarsenic acid, arsenic betaine, and arsenite) to obtain a powder sample. An aqueous solution of arsenate is added to the powder sample, and the resulting wet powder sample is then sequentially dried, pulverized, and mixed to obtain a standard quality control sample for edible fungi matrix containing multiple arsenic forms. This invention uses dried edible fungi samples as raw materials, and the prepared edible fungi matrix standard quality control sample is easy to preserve stably, and temporary sampling is less likely to induce arsenic form conversion. The method of this invention is simple, and the prepared edible fungi matrix standard quality control sample exhibits good uniformity and excellent stability. It can be used for the accurate quantification of inorganic arsenic in edible fungi, and through the qualitative determination of organic arsenic, it can effectively prevent false positives in inorganic arsenic results, effectively improving the accuracy and reliability of the detection results.

The invention discloses a device and a method for detecting the content of As (III) in a water body based on a paper-based micro-fluidic chip. The method is based on the chemical principle that arsenite reacts with potassium iodate under the acidic condition to generate an iodine simple substance, and rhodamine B is oxidized by the generated iodine simple substance under the catalytic action of a sulfuric acid medium and potassium bromide, so that the rhodamine B is subjected to a color fading reaction. According to the device, a fluid channel is prepared on a filter paper material, reagent dropwise adding areas and a reaction area are sequentially arranged, corresponding reagents are dropwise added into the reagent dropwise adding areas in sequence, then the reagents are converged to a main channel step by step through a micro-fluidic channel and are communicated to the reaction area, and the reagents are mixed in the micro-fluidic channel and subjected to a chromogenic reaction in the reaction area. The method comprises the following steps: shooting an image of a reaction area, extracting color parameters by using image processing software, and performing contrast calculation with a pre-established standard working curve to obtain the content of As (III) in the water sample. The technical problems that in the prior art, operation steps are complex, the detection period is too long, the detection portability of the arsenic content in the water body is poor, and the detection cost is too high are solved.

The present application belongs to the field of environmental microorganism and heavy metal pollution control technology, and particularly relates to a method for enhancing anaerobic arsenic oxidation of microorganisms in natural water system sediment system. The method retains the original microbial community of the natural water system sediment system, adds nitrate as an electron acceptor to the arsenic-containing sediment system, and introduces dissolved organic matter from the same water system raw water concentrate under light conditions to promote the conversion of arsenite to arsenate by microorganisms using its photosensitivity, thereby further enhancing the anaerobic oxidation process of arsenic. The present application does not require exogenous functional bacteria inoculation, artificial photosensitizer or electrode material, and can realize the oxidation and immobilization of arsenic under near-natural conditions, and is suitable for in-situ or near-in-situ regulation and remediation of arsenic pollution in sediment systems such as rivers, lakes, tailings ponds and paddy fields.

The invention belongs to the field of environmental protection, and discloses a method for recovering arsenic trioxide from arsenite-containing wastewater. According to the method, arsenite in the wastewater can be converted into arsenic trioxide, resource recycling of arsenic is achieved, waste is turned into wealth, and the problem of accumulation of a large amount of arsenic-containing solid waste generated by a traditional water treatment technology and the risk of secondary pollution are avoided. The method has the advantages of being short in technological process, high in arsenic recovery rate and the like, and has profound significance for improving the economic benefits of enterprises and walking a green and sustainable development road.

The invention discloses a method for determining the arsenic content in copper concentrate by combining microwave digestion and liquid phase atomic fluorescence, and relates to the technical field of determination of the arsenic content in ore, the method comprises the following steps: uniformly mixing a copper concentrate sample with nitric acid, hydrochloric acid and hydrofluoric acid, and carrying out microwave digestion pretreatment; preparing a standard working solution from the arsenite-arsenate standard working solution and a salpeter solution, injecting the standard working solution into a liquid-phase tandem atomic fluorescence spectrophotometer, and drawing a standard curve from the concentrations of As < 3 + > and As < 5 + > and corresponding peak areas; injecting into a liquid-phase tandem atomic fluorescence spectrophotometer for analysis to obtain a chromatogram, and determining the nature by retention time; and calculating the total inorganic arsenic content. According to the method, the microwave digestion pretreatment of the copper concentrate sample does not cause volatilization loss of arsenic element and does not damage the original valence state of arsenic in the sample; the digestion is complete, so that the determination result is accurate; the contents of trivalent arsenic and pentavalent arsenic in a copper concentrate sample are measured by adopting a liquid chromatography-atomic fluorescence tandem mode, and accurate, rapid and convenient quantification is realized.

The invention relates to a method for repairing arsenic-polluted soil. The method comprises the following steps that S1, a first positive electrode and a first negative electrode are inserted outside a to-be-repaired soil area; an electrolyte is applied to the soil area around the negative electrode; the first positive electrode and the first negative electrode are communicated with a power supply; after electrifying for 10 to 14 hours, standing for 10 to 14 hours; s2, exchanging electrodes; continuously electrifying for 10 to 14 hours, and standing for 10 to 14 hours; s3, detecting the content of pentavalent arsenic in the soil, and if the content is less than 85%, repeating the steps S1 and S2; and if the concentration is greater than 85%, removing the No.1 positive electrode and the No.1 negative electrode, and inserting the No.2 positive electrode and the No.2 negative electrode at the original electrode position. According to the method, the oxidizing agent is injected into the soil through electroosmosis, and trivalent arsenic in the soil is oxidized into pentavalent arsenic easy to stabilize; ferrous ions are introduced into the soil by utilizing the sacrificial positive iron electrode and are subjected to adsorption-precipitation reaction with arsenite and arsenate, so that the aim of stabilizing the arsenic-polluted soil is fulfilled.