259 results about "Nitrite salt" patented technology

The invention discloses a nitrifying bacterium agent suitable for aquarium, fishpond and other aquatic industries, the strain of the nitrifying bacterium agent is Glutamicacter nicotianae TJ-X, the nitrifying bacterium agent is preserved in Guangdong Microbial Culture Collection Center on February 12, 2025, and the preservation number is GDMCC NO.65877. The invention further discloses a preparation method of the nitrifying bacterium agent. The nitrifying bacteria TJ-X strain suitable for the aquarium industry can perform heterotrophic nitrification and aerobic denitrification under the condition that the salt content is 5wt%, under the condition of laboratory pure culture, within 8 hours, the removal rate of ammonia nitrogen, nitrite nitrogen and nitrate nitrogen is 99% or above, the COD degradation rate is 81%, the nitrifying bacteria TJ-X strain is suitable for the environment where organic matter, ammonia nitrogen, nitrite and nitrate coexist, and the nitrifying bacteria TJ-X strain can be applied to the aquarium industry. The microbial agent has the functions of degrading organic matters such as excrement of ornamental fish and fish food, converting organic nitrogen into inorganic nitrogen, and simultaneously degrading inorganic nitrogen such as ammonia nitrogen, nitrite nitrogen and nitrate nitrogen into nitrogen. And the strain is high in biological safety, high in environmental adaptability and high in growth density, can be applied to water industries with high organic matter content and inorganic nitrogen, such as the aquarium industry and aquaculture, and has a wide application prospect.

The application discloses a method for efficient denitrification and decarburization of kitchen waste and sludge co-fermentation anaerobic digestion effluent, which removes part of COD and ammonia nitrogen in the influent sludge by using a first SNAD, and maintains a certain amount of free ammonia of a certain concentration due to the high concentration of ammonia nitrogen and the high pH of the influent, so as to maintain the inhibition effect on nitrifying bacteria and ensure the conversion of part of the ammonia nitrogen into nitrite nitrogen, and the high activity of anaerobic ammonia oxidation bacteria is ensured in the first SNAD by limiting the aeration amount, so that the ammonia nitrogen and nitrite can be further removed; the effluent enters a nitrification tank, and the ammonia nitrogen is nitrified into nitrate nitrogen under the condition of nitrifying bacteria and sufficient aeration amount, and then enters a denitrification tank, and the denitrification process is carried out under the condition of heterotrophic denitrifying bacteria and sufficient carbon source, so that most of the nitrate nitrogen in the system is converted into nitrogen gas and removed, finally, the clear liquid is discharged after being filtered by an MBR membrane in a membrane tank, so as to achieve the purpose of efficient denitrification and decarburization of kitchen waste anaerobic digestion effluent.

The invention belongs to the field of microorganisms, and particularly relates to a high-efficiency denitrification heterotrophic nitrification-aerobic denitrification klebsiella and a culture method and application thereof.A biological material of the high-efficiency denitrification heterotrophic nitrification-aerobic denitrification klebsiella is named as Klebsiella oxytoca CT4 and is preserved in Guangdong Microbial Culture Collection Center (GDMCC) on July 21, 2025, the preservation number of the Klebsiella oxytoca CT4 is CGMCC NO.9687, and the preservation number of the Klebsiella oxytoca CT4 is CGMCC NO.987. The preservation address is Institute of Microbiology, Guangdong Academy of Sciences, on the fifth floor of building 59, No. 100 courtyard, Xianlie Middle Road, Guangzhou, Guangdong Province; the preservation number of the strain is GDMCCNO: 66723; according to the strain, the ammonia nitrogen removal rate can reach 98.7% through nitrification-denitrification, the nitrite accumulation amount in the whole process is lower than 0.5 mg / L, and accumulation of toxic intermediate products is avoided. The strain has wide environmental adaptability, can keep efficient denitrification activity under the conditions that the pH is 5.0-10.0 and the C / N ratio is 5-30, can tolerate fluctuation of wastewater quality, does not need to repeatedly adjust the pH value when being used for treating aquaculture wastewater with a high C / N ratio (greater than 20), and can still stabilize the total nitrogen removal rate to be 80% or above, so that the addition cost in a conventional process is remarkably reduced.

The pure membrane MBBR sewage treatment system comprises an anoxic denitrification zone, an anaerobic ammonia oxidation zone, an aerobic oxidation zone, a high-density sedimentation zone, an MBBR biological filtration zone, a backwashing water tank and an equipment room, the anoxic denitrification region is used for carrying out amination reaction, organic matter hydrolysis reaction and denitrification reaction on the sewage and nitrate and nitrite in the anoxic denitrification region; the anaerobic ammonia oxidation zone is used for reacting the sewage with nitrite to generate nitrogen; the aerobic oxidation zone is used for promoting microorganisms to degrade organic matters in sewage and convert ammonia nitrogen; the high-density settling zone is used for separating muddy water in sewage; the MBBR biological filtration area is used for filtering suspended matters in the sewage; the backwashing water tank is used for providing backwashing make-up water for the MBBR biological filtration area; and the equipment room is used for placing disinfection equipment, a fan and a power distribution control system.

The invention discloses a method for realizing deep autotrophic nitrogen removal of sludge digestion liquid based on alternate intermittent aeration of a double-membrane aeration bio-membrane reactor (MABR). The process device comprises a sludge digestion liquid raw water tank, a single-stage double-MABR reactor, two MABR devices and a water outlet tank. According to the method, sludge digestion liquid enters the single-stage double-MABR reactor, the two MABR devices are alternately and intermittently aerated, the state of one aeration and one aeration stopping is always kept, and ammonia nitrogen in raw water is converted into nitrite through ammonia oxidizing bacteria enriched on the inner side of an MABR membrane. And simultaneously supplying to anaerobic ammonium oxidation bacteria enriched on the outer sides of the two MABR membranes through matrix diffusion for denitrification and generation of nitrate. Denitrifying bacteria enriched on the outer side of the MABR membrane utilize raw water organic matters to drive short-cut denitrification to synchronously supply nitrite to anaerobic ammonium oxidation bacteria so as to realize deep autotrophic nitrogen removal. According to the invention, a double-anaerobic ammonia oxidation reaction hot area is constructed through alternate intermittent aeration of double MABRs, and efficient deep autotrophic nitrogen removal of the sludge digestion liquid can be stably realized.

The invention provides a domestic sewage treatment method and system based on shortcut nitrification and anaerobic ammonia oxidation of Anammox bacteria preposed alkali reduction, and relates to the technical field of sewage treatment. The method comprises the following steps: anaerobic treatment: converting an organic suspended solid into an easily degradable carbon source through hydrolytic acidification bacteria; the carbon source is absorbed by denitrifying phosphorus-accumulating bacteria and denitrifying glycogen-accumulating bacteria and is stored as an intracellular carbon source; primary anoxic treatment: reacting ammonia nitrogen with nitrite through Anammox bacteria, and synchronously reducing alkalinity; aerobic treatment: under the condition of low alkalinity, in combination with low dissolved oxygen control, Comamox bacteria oxidize ammonia nitrogen into nitrite and accumulate the nitrite; and secondary anoxic treatment: denitrifying residual oxidation nitrogen into nitrogen by using intracellular carbon through denitrifying glycogen-accumulating bacteria. Through the synergistic effect of the hydrolytic acidification bacteria, the denitrifying phosphorus-accumulating bacteria, the Anammox bacteria, the Commox bacteria and the denitrifying glycogen-accumulating bacteria, efficient nitrogen and phosphorus removal is realized.

According to the plasma high-efficiency water purification system and method suitable for factory-like circulating aquaculture, a water purification unit with a plasma secondary reaction technology as a core is constructed, and a low-energy-consumption cold plasma generator is used for pre-activating gas and introducing the gas into a water body in a micro-nano bubble form; further, an underwater SDBD cold plasma generator is utilized to secondarily excite the activated bubbles to obtain underwater micro-plasmas, and short-life ROS (reactive oxygen species) mainly comprising. OH is efficiently generated through a gas-liquid interface micro-discharge effect, so that pathogenic microorganisms and harmful components such as ammonia nitrogen and nitrite in aquaculture sea and fresh water are quickly and efficiently purified; an electrochemical reaction technology and an internal circulation technology are utilized to construct a plasma by-product elimination unit, the electrochemical reaction technology enables the biotoxicity of a water body to be rapidly reduced to a safe level, and the internal circulation technology avoids the problem of plasma reaction tail gas pollution.

The invention provides a sterile, injectable pharmaceutical composition which includes a therapeutically effective amount of ketamine or a pharmaceutically acceptable salt thereof, a nitrite scavenger, a tonicity agent, and water, wherein the composition contains less than about 300 ppb of an N-nitrosoketamine impurity. The invention also provides a pharmaceutical product which includes a container and the composition of the invention aseptically sealed therein. The invention further provides a process for preparing the composition and product of the invention.

This invention relates to the field of wastewater treatment technology, and more particularly to a method for anaerobic ammonia oxidation denitrification in a conductive membrane bioreactor for wastewater with low concentrations of nitrite. Anaerobic ammonia-oxidizing bacteria are inoculated into a conductive membrane bioreactor; the bioreactor is connected to a DC power supply, with a conductive membrane assembly as the cathode and a three-dimensional porous or fibrous conductive carbon material with a high specific surface area as the anode, and a positive bias is applied to the anode; nitrogen-containing wastewater with a nitrite to ammonia nitrogen molar ratio of 1:1.5 to 1:5 is introduced into the electro-enhanced membrane bioreactor, where the anaerobic ammonia-oxidizing bacteria use the conductive carbon material at the anode as an extracellular electron acceptor for biological denitrification. This invention, based on a conductive membrane bioreactor, achieves efficient denitrification even under nitrite-deficient conditions through a dual approach of "electroadsorption enrichment + electrostimulation enhancement." This method is simple to operate, energy-saving, and has broad application prospects.

The invention provides a liquid red direct dye and a preparation method thereof, and the method comprises the following steps: S1, dispersing 2-amino-5-naphthol-7-sulfonic acid and bis (trichloromethyl) carbonate in water, adjusting the pH value of a reaction system by using a first organic base, and reacting to obtain a scarlet acid aqueous solution; s2, dispersing a sulfo aromatic amine compound and nitrite in water, adjusting the pH value of a reaction system by using inorganic acid, reacting to obtain sulfo aromatic amine diazonium salt precipitate, and performing solid-liquid separation to obtain sulfo aromatic amine diazonium salt; and S3, adding the sulfonic aromatic amine diazonium salt in the step S2 into the scarlet acid aqueous solution in the step S1, adjusting the pH value of the reaction system by using second organic alkali, and reacting to obtain the liquid red direct dye. Through the preparation method, the red direct dye which can stably exist in a liquid form and is suitable for direct use can be obtained.

The invention discloses a sewage denitrification component based on compounding of MABR (Membrane Aerated Baffled Reactor) and flora colonization gel membrane filaments. According to the component, oxygen-permeable MABR membrane filaments and flora ecological colonization gel membrane filaments are packaged in a shell. Aerobic bacteria are enriched on the surface of the oxygen-permeable MABR membrane filaments by utilizing the oxygen-permeable characteristic of the oxygen-permeable MABR membrane filaments, so that short-cut nitrification from ammonia nitrogen to nitrite is realized; mutually-communicated micron-sized porous structures are arranged in the flora ecological planting gel membrane filaments, anaerobic ammonium oxidation bacteria can be loaded and protected in a high-density mode, the gel material wraps and slowly releases premixed nutrients, and flora activity is maintained. Through the spatial adjacent arrangement of the two membrane filaments, efficient coupling of short-cut nitrification and anaerobic ammonium oxidation is realized, and anaerobic ammonium oxidation bacteria directly utilize generated nitrite and residual ammonia nitrogen to generate nitrogen, so that efficient denitrification is completed in a single component. The design effectively solves the problems that anaerobic ammonium oxidation bacteria are difficult to enrich and are easily inhibited by dissolved oxygen, and has the advantages of high denitrification efficiency, low energy consumption, quick start, stable operation and the like.

The invention relates to the technical field of analytical chemistry detection, in particular to a method for determining trace nitrite in pharmaceutic adjuvants.The method comprises the steps that an acetonitrile solution, a potassium hydroxide solution, a phosphate buffer solution, a sulfuric acid solution, a 2, 3-diaminonaphthalene solution and a reference substance working solution are provided; the method comprises the following steps: preparing a standard curve solution and a test sample solution, and carrying out ultra-high performance liquid chromatography-tandem mass spectrometry analysis detection: respectively carrying out sample injection detection on the test sample solution and the prepared standard curve solutions with different concentrations under preset chromatographic conditions and mass spectrometry conditions, recording detection results of the standard curve solutions with different concentrations to make a standard curve, and calculating the content of nitrite in the test solution by adopting a standard addition method according to the standard curve and the detection result of the test solution. The method disclosed by the invention can be used for rapidly determining trace nitrite in a drug sample, and can be used for determining the trace nitrite in pharmaceutical adjuvants and detecting the nitrite in drugs.

The invention relates to the technical field of sewage treatment, in particular to a greenhouse gas emission control method and system applied to sewage nitrification treatment.The greenhouse gas emission control method is implemented in an aerobic treatment unit in a sewage digestion treatment system, and in the aerobic treatment unit, the sewage is subjected to nitrification treatment; arranging a front-section measuring point and a rear-section measuring point along the main flow direction of the mixed liquid, and periodically acquiring a first nitrite concentration time sequence at the front-section measuring point and a second nitrite concentration time sequence at the rear-section measuring point respectively; respectively configuring a front-section oxygen supply device and a rear-section oxygen supply device based on the front-section measuring point and the rear-section measuring point, controlling an oxygen supply base line of the front-section oxygen supply device based on the change trend of the first nitrite concentration time sequence and the second nitrite concentration time sequence, and controlling a short-time oxygen reduction control window of the rear-section oxygen supply device; wherein the oxygen supply base line is a preset oxygen supply level executed by the front-section oxygen supply device, and the short-time oxygen reduction control window carries out oxygen supply reduction or intermittent time arrangement for the rear-section oxygen supply device.

1. The name of the design product: full-spectrum multi-parameter water quality online analyzer (SECCO-L-1905). 2. The use of the design product: for analyzing and detecting key water quality indicators such as total phosphorus, total nitrogen, COD, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, etc. in water, online monitoring, fixed and mobile monitoring of water quality in "source-net-plant-river" multiple scenes, and water pollution prevention and supervision. 3. The design points of the design product: the combination of the shape and pattern of the product as a whole. 4. The picture or photo that best indicates the design points: perspective view 1.

The application relates to a method and device for degrading ethion and recycling heavy metals simultaneously based on an endogenous sulfur cycle, and belongs to the technical field of dressing wastewater treatment. The device is mainly composed of sequentially connected MABR and H2-MBfR. In the method, ethion is oxidized and degraded to produce CS2 and ammonia nitrogen under aerobic conditions in the MABR, and the CS2 is further converted into sulfate; the ammonia nitrogen is nitrified into nitrate nitrogen and nitrite nitrogen. Subsequently, the effluent enters the H2-MBfR, and under anaerobic conditions, the nitrate nitrogen and the nitrite nitrogen are reduced into nitrogen gas by taking hydrogen as an electron donor, and the endogenous sulfate is reduced into sulfur ions; the sulfur ions react with heavy metal ions in situ to generate metal sulfide precipitates. Finally, the precipitates are recovered through solid-liquid separation and are reused for metal flotation. The application realizes directional conversion and collaborative removal of pollutants, does not produce secondary pollution, and realizes recycling of heavy metal resources by using the sulfur element of the pollutants.

A device and a method for maintaining the stability of anaerobic ammonium oxidation (anammox) by using a combined zeolite filler to resist water quality fluctuations are provided. The device includes a water inlet tank, an anammox reactor, and a water outlet tank, where the anammox reactor is filled with the combined zeolite filler maintained in a state of suspension, domestic sewage enters the anammox reactor through a water inlet pump, and effluent water enters the water outlet tank through an overflow port. The device combines the physical characteristics of zeolite adsorption of ammonium with the anammox process: when the concentration of ammonium in the influent water is too high, the zeolites will temporarily store the excess ammonium adsorbed; when the concentration of nitrite in the influent water is too high, the zeolites are capable to release the stored ammonium into a liquid phase through balanced adsorption desorption.

This invention discloses a method for preparing an aromatic amine-free organic pigment yellow, comprising the following steps: S1, preparing a diazo solution by sequentially adding water, inorganic acid, and diazo components to a diazo tank, stirring and slurrying, then cooling the mixture in the diazo tank to below 0°C and adding nitrite; S2, preparing a coupling solution by sequentially adding water, inorganic alkali, and coupling components to a dissolving tank, stirring and dissolving until clear; S3, coupling reaction by adding water, acetic acid, and surfactant to a coupling tank, stirring and mixing evenly, then slowly adding the diazo solution and coupling solution simultaneously to the coupling tank for a coupling reaction; S4, pigmentation by heating to above 60°C and maintaining the temperature, adjusting the pH of the solution to alkaline; S5, filtering, washing, and drying to obtain an aromatic amine-free organic pigment yellow. This invention is applicable to the synthesis of most mono- and diazo organic pigment yellows, reducing aromatic amine residues during the synthesis process and ensuring that the organic pigment yellow product is free of aromatic amine residues.

The invention discloses a preparation method of a spherical carbon nano polymer steel slag cement grinding aid, which comprises the following steps: (1) mixing and dissolving a polycarboxybenzene compound, an amino alcohol compound and a condensing agent in an organic solvent to prepare a solution A, stirring and activating at a first temperature, then keeping stirring and heating to a reaction temperature, and reacting at a certain pressure to obtain a reaction solution B; after the reaction is finished, centrifuging and taking supernate, and filtering to obtain a polymer solution; (2) mixing the obtained polymer solution with hydrochloric acid to prepare a solution B, placing the solution B in an ice salt bath, dropwise adding a nitrite solution, and stirring for a first reaction; and adding thiocyanate and a cuprous salt catalyst, removing the ice salt bath, heating, carrying out a second reaction, and cooling to room temperature after the reaction is finished to obtain the spherical carbon nano polymer steel slag cement grinding aid. The grinding aid can improve the grinding efficiency of the steel slag cement, the performance of the steel slag cement is improved, and the process is simple and efficient.

A method of treating a subterranean formation by contacting the formation with the following (a) ammonium bicarbonate; (b) an oxidizing agent selected from a perchlorate or a nitrite or combinations thereof; and (c) an acid (AA).

The present application relates to the technical field of detection, and relates to a preparation method of an oxygen-rich vacancy Mn3O4 nanoscale enzyme, and the method comprises the following steps: step one: adding KMnO4 into deionized water according to a ratio of 0.5-1.5 g:500 ml, and completely dissolving to obtain a mixed solution; step two: adding oleic acid according to a volume ratio of 1:50, and continuously stirring at 25-35 DEG C for 4-6 hours; step three: collecting the precipitate, washing with deionized water and ethanol alternately for 4-6 times, drying at 70-90 DEG C for 8-12 hours, and calcining at 180-220 DEG C for 4-6 hours, so as to obtain an oxygen-rich vacancy Mn3O4 nanoscale enzyme with oxidase activity; and the oxygen-rich vacancy Mn3O4 nanoscale enzyme can detect nitrite rapidly, sensitively and specifically.

This invention belongs to the field of wastewater denitrification technology, specifically an integrated zoned denitrification method based on anaerobic ammonia oxidation reaction, comprising the following steps: S1, removing high concentrations of organic matter and suspended solids from wastewater through coagulation sedimentation or chemical oxidation pretreatment to avoid inhibition of subsequent Anammox treatment; S2, dividing the integrated reactor into zones, setting up a short-cut nitrification zone and an Anammox reaction zone; S3, partially recirculating the effluent from the Anammox reaction zone back to the short-cut nitrification zone to replenish nitrite and balance the carbon-nitrogen ratio; recirculating Anammox granular sludge to the reaction zone through a sedimentation zone to maintain biomass concentration and reaction efficiency; S4, setting up a secondary sedimentation tank or an internal sedimentation zone to achieve sludge-water separation, discharging excess sludge and ensuring effluent meets standards. This invention ensures stable denitrification efficiency by dynamically adjusting the dissolved oxygen in the short-cut nitrification zone and the pH value in the Anammox reaction zone.

The invention belongs to the technical field of metal anti-rust treatment, and particularly relates to an environment-friendly water-based anti-rust composition as well as a preparation method and application thereof. The composition is prepared from the following components in parts by weight: 3 to 8 parts of a first triazine compound, 1 to 5 parts of a second triazine compound, 10 to 20 parts of 2-amino-2-methyl-1, 3-propylene glycol, 2 to 5 parts of dipropylene glycol monomethyl ether and 65 to 85 parts of water, the first triazine compound is a triazine compound with a substituent group containing a hydrophobic chain segment and at least two amino carboxylic acid substituent groups, and the second triazine compound is a triazine compound with a sulfydryl substituent group. The coordination bond and covalent bond dual anchoring protective film is formed on the metal surface through the two triazine compounds, the excellent salt mist resistance, humidity and heat resistance and film forming compactness are achieved, the salt mist test time reaches 72 hours, the humidity and heat test time reaches 960 hours, the adhesive force is 0 grade, and nitrite, phosphate and heavy metal are not contained. The preparation method is simple and convenient, is suitable for industrial production, and can be widely applied to metal anti-rust treatment in the fields of mechanical manufacturing, automobile parts and the like.

The invention relates to the technical field of water body remediation, and particularly discloses a trichoderma sp. XH5, a hybrid system as well as a construction method and application of the trichoderma sp. XH5, the trichoderma sp. XH5 is preserved in China Center for Type Culture Collection on September 29, 2025, the preservation number is CCTCC: M 20252142, and the trichoderma sp. XH5 is classified and named as Trichoderma sp. XH5. The Trichoderma sp. XH5 provided by the invention has the capability of denitrification, and specifically, the removal rate of nitrate, total nitrogen and nitrite is improved.

The partitioned aeration internal circulation up-flow short-cut nitrification and anaerobic ammonia oxidation reaction system is characterized by simple design structure of the main reactor, the aeration head arranged in the middle of the internal circulation up-flow reactor, the formation of the aerobic region and the anoxic region in the upper part and the lower part of the single reaction zone respectively, the suitable growth environment of the aerobic ammonia oxidation microorganism and the anaerobic ammonia oxidation bacteria in the single reactor, the nitrite produced by the aerobic ammonia oxidation microorganism in the aerobic region of the upper part of the reactor can re-enter the anoxic region of the lower part of the reactor through the internal circulation route of the reaction zone to supply the growth of the anaerobic ammonia oxidation bacteria in the anoxic region, and the improvement of the overall denitrification efficiency of the reactor. The present application belongs to the technical field of wastewater denitrification.

The present invention discloses a method for the rapid formation of denitrifying granular sludge and enhanced denitrification of high-nitrate nitrogen wastewater, belonging to the technical field of wastewater treatment. The method involves colonizing the succinic acid-producing microorganism A. succinogenes into sewage sludge. By leveraging its high adhesiveness and its promoting effect on denitrifying microorganisms, the method rapidly forms denitrifying granular sludge while simultaneously enhancing the denitrification of high-nitrate nitrogen wastewater. The method is simple to operate, requires no additional pH control, and generates no secondary pollution. It enables the rapid formation of stable, full-process denitrifying granular sludge, which reduces the system's acclimation period to high-nitrate wastewater, shortens the sludge cultivation cycle, and minimizes the accumulation and discharge of intermediate products, such as nitrite, during denitrification.

According to the dynamic environment regulation and control detection device and method for the urban external nitrogen oxide absorption coating, the absorption effect of the coating on nitrogen oxide in the environment is systematically analyzed through multi-dimensional dynamic environment simulation and surface chemical in-situ analysis. According to the invention, a spectrum-pollutant-mechanical stress synergistic effect dynamic simulation system is constructed, and a spectrum-adjustable LED array, a NOx pulse injection module and a temperature and humidity-wind speed composite cavity are adopted, so that coupling simulation of dynamic adjustment of ultraviolet intensity, pollutant pulse input and rapid switching of temperature and humidity is realized; a surface adsorption state real-time monitoring technology is innovatively introduced, the characteristic peak intensity ratio of nitrate to nitrite is analyzed through a micro FTIR probe, and a coating layer micropore blockage early warning mechanism is established.

The invention provides a sulfur autotrophic denitrification sulfur source stable supply method based on a sulfur source effectiveness evaluation model, which comprises the following steps of: calculating electrons required by nitrate and nitrite in inlet water by establishing an electron dosage standard taking electron equivalent as a core, and obtaining a theoretical sulfur electron number from sulfide, sulfur-containing salts, amines and iron in absorption liquid; constructing a correction model taking an absorption liquid index, a redox value, dissolved oxygen and a replacement interval as inputs and a single adjustment coefficient as an output, and obtaining a corrected sulfur electron number; the method comprises the following steps: under a first-calculation and second-adjustment combined band limitation scheme of setting an allowable operation range of the sulfur / nitrate electron ratio, calculating a sulfur adding flow according to a required electron number, setting a sulfur adding upper limit by combining sulfate growth and a redox value, and performing small-amplitude post-adjustment and coefficient updating according to residues of nitrate and nitrite in effluent. Nitrate leakage is avoided, excessive sulfate is inhibited, the corrosion risk is reduced, and stable supply is achieved.

The application relates to a nitrite reductase electrode and a preparation method thereof and an electrochemical system. The nitrite reductase electrode comprises a substrate layer and n electron transfer layers and n enzyme activity layers in the form of alternating layers above the substrate layer, n is in the range of 2-30, wherein the substrate layer comprises a carbon-based electrode loaded with a transition metal phosphide, and the enzyme activity layer comprises a nitrite reductase. The nitrite reductase electrode has low detection limit, high sensitivity, high enzyme loading rate, high electrocatalytic efficiency and good application prospect.

The invention discloses a carbon dioxide triggered expanded graphite channeling inhibitor and a preparation method, and belongs to the technical field of oil-gas field development, and the preparation method comprises the following steps: dispersing aminated graphite in distilled water to obtain aminated graphite dispersion liquid, adding nitrite into the aminated graphite dispersion liquid, and uniformly stirring to obtain the carbon dioxide triggered expanded graphite channeling inhibitor. The mass ratio of the nitrite to the aminated graphite in the S1 is (8-12): (5-10), and the carbon dioxide triggered expanded graphite anti-channeling agent solves the problem that solid-phase residues generated after degradation of the anti-channeling agent permanently block reservoir pores and cause productivity reduction, after nitrogen in a graphite layer completely escapes, the plugging effect on cracks is weakened, unblocking of the plugging agent is achieved, and the problem that the productivity is reduced is solved. And the problem of permanent loss of rock stratum permeability does not exist.

A coated nanocluster (10) comprises: a core (20) including an aggregate of magnesium oxide particles; and a shell (30) covering the core (20). The shell (30) has a coating layer (31) containing at least one of a nitrate and a nitrite, and carbonate particles (32) dispersed in the coating layer (31). At least one of the nitrate and the nitrite contains an alkali metal ion. The carbonate particles (32) contain at least one selected from a calcium ion, a strontium ion, and a barium ion. The molar ratio of the carbonate particles (32) constituting the shell (30) to the magnesium oxide particles constituting the core (20) is more than 0.005 and 0.015 or less.