18 results about "Dissolved nitrogen" patented technology

The invention relates to the field of soil nitrogen fixation, in particular to nitrogen fixation biochar particles and a preparation method and application thereof. The preparation method of the nitrogen-fixing biochar particles provided by the invention comprises the following steps: pyrolyzing a biomass raw material to obtain pyrolytic carbon; mixing the pyrolytic carbon with a strong alkali solution, and reacting to obtain nitrogen-fixing biochar particles; the strong base in the strong base solution is alkali metal hydroxide. The number of oxygen-containing functional groups on the surfaces of the nitrogen-fixing biochar particles is increased by adopting strong base modification, and meanwhile, the specific surface area and the porosity of the nitrogen-fixing biochar particles are increased; the method reduces migration of dissolved nitrogen, facilitates fixation of nitrogen in the soil, effectively relieves nitrogen runoff and leaching loss caused by application of nitrogen fertilizer in the soil, improves the utilization rate of the nitrogen fertilizer, and relieves the pollution problem of lake water around a farmland.

The present invention relates to a method for purifying liquid argon by removing nitrogen using the adsorbent (molecular sieve) Li-FAU. More specifically, the invention aims to describe a method for capturing dissolved nitrogen to produce liquid argon with a high degree of purity, for the purpose, among other applications, of studying the behaviour of neutrinos in experiments that require massive quantities of ultra-pure liquid argon, for which there is as yet no industrial process.

The invention discloses a sodium alginate sealed semi-dry calcium-based desulfurized fly ash slow-release material as well as a preparation method and application thereof, and belongs to the technical field of material modification preparation. Through the synergistic effect of the sodium alginate and the desulfurized gypsum, encapsulation and fixation of the desulfurized gypsum by the sodium alginate are synchronously completed to obtain the sustained-release material, the release speed of the SFGDA in a water body is delayed, the situation that the pH is strongly alkaline and violently fluctuates is avoided, the problems of water body pollution and the like caused by direct application of traditional SFGDA are solved, and the preparation method is simple and convenient to operate. The mechanical stability and adsorption efficiency of the material are improved, the water quality of a water body is effectively improved, the survival rate of submerged plants is increased, the concentration of nitrogen and phosphorus dissolved in the water body is reduced, the eutrophication phenomenon of the water body is prevented, and high efficiency, durability and environmental friendliness of water body remediation are achieved. The preparation method disclosed by the invention is simple to operate and low in cost, and has a good application prospect.

A process to prepare an aqueous fertilizer with a high nitrogen content, said process comprising the steps of: —providing a solid material having a high nitrogen content; —providing a live yeast in solution adapted to enzymatically removing nitrogen-containing compounds from said solid; —exposing said solid to said yeast in an aqueous environment, thereby creating a metabolically active culture mixture; —incubating said metabolically active culture; —injecting air in to the metabolically active mixture during said incubating step so as to inhibit the production of ethanol; wherein said metabolically active mixture undergoes said incubating step for a period of time sufficient to result in a nitrogen-fed yeast mixture; —hydrolyzing (by autolysis) the resulting nitrogen-fed yeast mixture for a period of time sufficient to remove nitrogen from said yeast, where the nitrogen removed from said yeast is present in the mixture as dissolved nitrogen.

The present application relates to soil remediation and improvement technical field, especially to a kind of method for soil fertility recovery after soil electrokinetic remediation and application thereof, comprising the following steps: soil basic parameter detection: the soil after electrokinetic remediation is zoned, and the pH value, alkali-dissolving nitrogen, available phosphorus, available potassium content and moisture content of each region soil are detected respectively;pH precision regulation: according to the pH value of each regional soil, pH is adjusted using differential reagent, to reach the suitable growth interval of crops;Quasi-nutrient supplement: based on the nutrient deficiency amount of detection analysis, combined with the nutrient amount brought in during pH adjustment process, calculate and supplement nitrogen, phosphorus and potassium fertilizer;Add soil conditioner to soil, mix evenly after ploughing, adjust soil moisture content, cover film maintenance, complete soil fertility recovery.The present application effectively solves the problem that traditional technology cannot zoned differential regulation of electrokinetic remediation soil acid and alkali, pH adjustment, nutrient supplement and structure improvement cannot be synchronized, fertility recovery is slow, and farmland reclamation is lagging behind.

The invention discloses a method for estimating contribution of ectomycorrhizal fungi to acquisition of nitrogen of abies regale and betula platyphylla, and relates to the technical field of plant nitrogen acquisition contribution estimation.The method comprises the steps that leaf, stem and root samples of ectomycorrhizal trees in a target area and soil samples under the ectomycorrhizal trees are collected; measuring the leaf, stem and root samples, and determining nitrogen stable isotope values and nitrogen contents of the leaf, stem and root samples; measuring the soil sample, and determining a nitrogen stable isotope value of total dissolved nitrogen of the soil sample; and according to the nitrogen stable isotope values and the nitrogen contents of the leaf, stem and root samples and the nitrogen stable isotope value of the total dissolved nitrogen of the soil sample, calculating by adopting an isotope mass balance model and an isotope mixing effect model to obtain the contribution rate of ectomycorrhizal fungi to obtain the nitrogen of the ectomycorrhizal tree. According to the method, the accuracy of estimating the nitrogen acquisition contribution of the ectomycorrhizal fungi to the abies regale and the betula platyphylla can be improved.

The invention discloses an enrichment and purification device and method for testing stable isotopes of trace dissolved nitrogen in a water body, and relates to the field of stable isotope analysis and testing. Comprising a device for oxidizing nitrogen elements dissolved in water, a gas purification device, a nitrogen oxide freezing enrichment device, a micro nitrogen oxide reduction device, a nitrogen separation and purification device and a stable isotope ratio mass spectrometer which are arranged in sequence. According to the method, trace dissolved nitrogen in the water body is oxidized into nitrogen oxide at high temperature, the generated nitrogen oxide is subjected to liquid nitrogen freezing enrichment, enriched sample gas is reduced into nitrogen gas through a miniature reduction tube, and then the nitrogen gas is introduced into a stable isotope ratio mass spectrometer, so that the trace dissolved nitrogen isotope in the water body is tested.

The invention relates to the technical field of environmental protection, and discloses an agricultural non-point source pollution ecological interception process which comprises the following steps: applying a hydrogel precursor solution prepared from carboxymethyl chitosan, polyphosphate and modified charcoal on the surface of farmland soil to form a first physical barrier, and pretreating surface runoff. And guiding the pretreated runoff into an ecological ditch provided with an ionic liquid functionalized intelligent response liquid film for deep purification. The liquid membrane is water-in-oil emulsion, the core of the liquid membrane is functionalized ionic liquid containing ureido functional groups, and the ionic liquid serves as an active carrier, can specifically capture dissolved nitrogen and phosphorus in runoff and transfers the dissolved nitrogen and phosphorus into an inner water phase containing enzyme and microorganisms to be converted. Under the triggering of plant root exudates, the converted nutrient substances can be controlled to be released from the liquid film and can be absorbed and utilized by plants. Through the synergistic effect of the field-ditch double barriers, efficient purification and in-situ closed-loop recycling of pollutants are achieved.

The present application relates to the technical field of water quality monitoring, in particular to a regional water environment risk assessment system considering the influence of water ecology and resident life, which comprises a water temperature and flow velocity module, an ecological analysis module, a pollution analysis module, a risk assessment module and an optimization assessment module.In the present application, water temperature, flow velocity and resident water consumption are collected and subjected to periodic characteristic separation, the synchronous change rate of temperature and water consumption behavior is analyzed to calculate the thermal disturbance intensity, the water ecological thermal response characteristic set is generated, the concentrations of dissolved oxygen, dissolved nitrogen, dissolved phosphorus and chlorophyll a are collected for correlation analysis, the ecological energy metabolism coordination coefficient is calculated to generate the ecological stability sequence, the residual chlorine and soluble organic carbon concentrations in the water supply path are detected to calculate the pollutant concentration fluctuation rate, the thermal disturbance intensity is combined to generate the pollution activation sequence through probability classification, the pollution migration rate is deduced and the risk time sequence data is fitted to generate the regional water environment risk optimization result.

This invention discloses a method for preparing large-size ultrathin C2N nanosheets and their applications. The preparation method includes the following steps: (1) dissolving nitrogen-containing precursor molecules and adding them to a soluble metal salt, then mixing; (2) drying the system obtained in step (1) and annealing it under a protective atmosphere; (3) cooling the annealed product to room temperature, adding deionized water to dissolve the soluble metal salt; letting the system obtained in step (3) stand overnight, vacuum filtering, washing, and freeze-drying the product to obtain large-size ultrathin C2N nanosheets. The C2N nanosheets prepared by this invention have good application prospects in the field of energy storage and conversion. The prepared C2N nanosheet material can be used as a negative electrode material for sodium-ion batteries. The initial reversible capacity was tested to reach 700mAh / g to 1000mAh / g, and the capacity retention rate was about 90% after more than 100 cycles.

The present invention provides a method for treating organic wastewater by biologically treating the organic wastewater in an aerobic condition using a reaction tank (12) having a carrier (44), wherein the biological treatment is carried out by maintaining the dissolved phosphorus concentration in the reaction tank (12) at 0.5 mg / L or less and maintaining the dissolved nitrogen concentration in the reaction tank (12) at 3 mg / L or more.

To provide a measuring device capable of accurately measuring the amount of dissolved nitrogen gas excessively dissolved in sewage in an activated sludge tank.SOLUTION: The measuring apparatus 10 is provided with a collecting vessel 20 for collecting waste water, an ultrasonic oscillator 1 for transmitting ultrasonic waves to the waste water in the collecting vessel 20, and a collecting vessel 4 for collecting gaseous nitrogen generated in the collecting vessel 20, and the collecting vessel 20 is provided with a storage vessel 21a made of a soft resinous material and an opening / closing mechanism 22 for switching the collecting vessel 20 between an open state and a closed state. Only nitrogen gas excessively dissolved in wastewater containing activated sludge in excess of a saturation amount is degassed by irradiating the wastewater in a collection container 20 with ultrasonic waves from an ultrasonic oscillator 1 and the degassed nitrogen gas is transferred to a collection container 4 to measure the concentration of degassed nitrogen.SELECTED DRAWING: Figure 1

The invention discloses a method for measuring dissolved nitrogen in a primary loop coolant of a reactor, which comprises the following steps of: S1, separating the dissolved nitrogen in the primary loop coolant by adopting a phase separator to obtain mixed gas containing nitrogen; s2, analyzing through a gas chromatograph to obtain the nitrogen content in the mixed gas; and S3, calculating the content of dissolved nitrogen in the primary loop coolant according to the nitrogen content. The invention provides an analysis method for nuclear power plant primary loop coolant dissolved nitrogen. The scheme is simple in operation process, accurate and sensitive in measurement result, capable of meeting the requirement for measuring the dissolved nitrogen in the primary loop, and capable of being popularized and used in other nuclear power plants needing to measure the dissolved nitrogen.

The invention provides a phosphorus-solubilizing nitrogen-fixing recarburization functional bacterium and application thereof in fertile soil growth promotion, and belongs to the technical field of agricultural microorganisms. The rahnella maple ZC-7 is preserved in the China Center for Type Culture Collection, the preservation number is CCTCC NO: M 20252883, the preservation time is December 15, 2025, and the preservation address is Wuhan University. The strain has the effects of dissolving phosphorus, fixing nitrogen, producing IAA and the like. In addition, the strain is wide in carbon source utilization spectrum, has resistance to various chemical substances and can adapt to various soil environments. The strain can obviously promote the growth of corn plants and increase the corn yield, and field tests show that the use of chemical fertilizers can be reduced and the corn yield can be increased by 27% by applying a microbial agent containing the strain. The strain has comprehensive functions and strong adaptability, provides technical support for green agriculture development, and has important application value.

This invention discloses a method for dissolving dual-labeled nitrogen gas in water ( 15 The preparation and quantification method of N2 standard samples belongs to the field of stable isotope analysis technology. This method will... 15 N-labeled ammonium chloride solution reacts with sodium hypochlorite in a completely sealed reaction flask filled with liquid and without a headspace, resulting in in-situ formation and dissolution. 15 N 15 Nitrogen gas was directly measured in its dissolved state in the liquid phase using membrane sample mass spectrometry (MIMS). 15 N 15 The m / z 30 characteristic signal of N was obtained by simultaneously monitoring the concentrations of residual monochloramine, dichloramine, and trichloramine in the reaction solution, and corrected based on the principle of nitrogen conservation. 15 N 15 The true concentration of nitrogen (N). This invention eliminates the need for gas collection, transfer, and cold trap purification throughout the entire process, avoiding nitrogen escape losses; chloramine correction significantly improves quantitative accuracy. It is simple to operate and allows for the flexible preparation of a series of concentration standards ranging from 10 to 1000 μmol / L. The signal drift of the standards is less than 3% within 30 days, making it suitable for isotope ratio mass spectrometry calibration, denitrification tracing, and isotope analysis of dissolved nitrogen in environmental water samples.

This invention relates to the fields of ultrapure stainless steel smelting, nitrogen removal from molten steel, and steelmaking heat balance. A method for smelting ultrapure 409 series steel using AOD (Alkali Oxide) includes the following steps: Step 1: After the blast furnace hot iron undergoes three decarburization treatments to achieve P≤0.025%, AOD is added for carbon removal; Step 2: In the initial stage of decarburization, inert gas is blown from the side of the AOD to remove dissolved nitrogen from the molten steel using CO generated from the carbon-oxygen reaction; Step 3: When the carbon content in the molten pool decreases to 0.3-0.4%, the molten pool temperature is corrected by measuring the temperature of the molten steel in the furnace using a secondary lance, and the total amount of ferrosilicon to be added is calculated based on the measured temperature and the total oxygen blowing volume; Step 4: During the decarburization period, the slag basicity is controlled at 1.8-2.0, and the amount of lime added = total metal content * silicon content * 2.14 * 2.0 / 0.85. No more lime is added after the temperature rises following the addition of ferrosilicon; Step 5: After sampling to confirm the composition of the molten steel, the temperature and composition of the molten steel are adjusted. At the end of the oxidation process, the temperature of the molten pool is rapidly increased to 1700-1720℃ by adding ferrosilicon, so as to achieve preferential oxidation of carbon and chromium, thus achieving decarburization and chromium preservation and improving chromium yield.

The present application discloses a method for estimating the contribution of ectomycorrhizal fungi to nitrogen acquisition by Abies minjiangensis and Betula sclerosa, which relates to the technical field of estimating the contribution of plants to nitrogen acquisition. The method comprises collecting leaf, stem and root samples of ectomycorrhizal trees in a target area and soil samples directly below the ectomycorrhizal trees; measuring the leaf, stem and root samples to determine the nitrogen stable isotope values ​​and nitrogen contents of the leaf, stem and root samples; measuring the soil sample to determine the nitrogen stable isotope value of the total dissolved nitrogen of the soil sample; and calculating the contribution rate of ectomycorrhizal fungi to nitrogen acquisition by ectomycorrhizal trees using an isotope mass balance model and an isotope mixing effect model based on the nitrogen stable isotope values ​​and nitrogen contents of the leaf, stem and root samples and the nitrogen stable isotope value of the total dissolved nitrogen of the soil sample. The present application can improve the accuracy of estimating the contribution of ectomycorrhizal fungi to nitrogen acquisition by Abies minjiangensis and Betula sclerosa.

The invention discloses a phosphorus-dissolving and nitrogen-fixing type soil improvement and yield increase microbial agent, and particularly relates to the technical field of agricultural biology. The microbial inoculum takes sulfur modified porous ceramic microbeads as a carrier matrix, and a manganese / iron co-doped zeolite nanosheet and a functional layer of nano calcium carbonate coated with a lignin derived porous carbon shell are compounded on the surface of the carrier matrix. The preparation method comprises the following steps: carrying out sintering and vapor deposition to obtain elemental sulfur-loaded porous ceramic microbeads, preparing manganese / iron co-doped zeolite nanosheets, synthesizing a porous carbon shell coated nano calcium carbonate composite material, compounding the components to form a carrier, and finally loading a mixed bacteria solution of phosphorus-dissolving microorganisms and nitrogen-fixing microorganisms on the carrier, thereby obtaining the nitrogen-containing phosphorus-dissolving nitrogen-fixing composite material. And embedding and immobilizing to obtain the microbial inoculum. Competition and inhibition among strains are effectively reduced, the storage stability of the microbial inoculum and the lasting activity in soil are remarkably improved, and the microbial inoculum is suitable for soil improvement and crop yield increase.