13 results about "Phosphate loading" patented technology

The present invention discloses a phosphate detection method using a colorimetric method and electrochemical test paper, which belongs to the field of environmental monitoring. Specifically, the phosphate content in the water body is first semi-quantitatively detected by standard colorimetric test paper, and then the electrochemical test paper with a paper base is used to select cyclic voltammetry or square wave pulse voltammetry according to the colorimetric result to detect the phosphate concentration in the water body; when the phosphate content calculated as phosphorus in the colorimetric result is higher than 5 mg / L, the water sample is diluted by half and then detected by cyclic voltammetry; when the phosphate content calculated as phosphorus in the colorimetric result is within the range of 0.5 to 5 mg / L, cyclic voltammetry is used for detection; when the phosphate content calculated as phosphorus in the colorimetric result is lower than 0.5 mg / L, square wave pulse voltammetry is used for detection. The detection process of the present invention does not require the addition of other reagents, has a wide and accurate detection concentration range, and can achieve simple and fast in-situ detection of phosphate.

To provide a method for reducing precipitation in bacterial fermentation processes. [Solution] A method comprising the steps of a) culturing host cells for bacterial growth in a batch phase using a batch medium, and b) culturing host cells in a fed batch phase to produce a fermentation product using a feed medium, wherein the feed medium and the batch medium are each non-precipitated medium solutions, i) the batch medium comprises calcium salts, magnesium salts, phosphates, and at least one chelating agent which is at least 5 mM citrate and / or citric acid and / or at least 1 mM EDTA, ii) the feed medium contains at least 1 mM of calcium salts which is at least 5 times higher than that of the batch medium, iii) the feed medium contains at least 3 mM of magnesium salts which is at least 2 times higher than that of the batch medium, and iv) the feed medium contains less than 90% of the amount of phosphates contained in the batch medium.

The invention belongs to the field of analytical chemistry, and particularly relates to a method for analyzing a phosphate detection sample in food, especially aquatic products. The method realizes high-efficiency detection of phosphate through combination of water extraction and XRF, and comprises the following steps: sample preparation and extraction: unfreezing a frozen aquatic product, then carrying out high-speed crushing at a speed of 22000 r / min, carrying out vortex mixing on an aqueous solution, carrying out ultrasonic extraction for 3-15 min, carrying out centrifugal treatment at a speed of 8000 r / min, and taking a supernatant; establishing a matrix labeling standard curve: adding a sodium phosphate standard substance (0-529.14 mg) into the sample, extracting to obtain a standard working solution with the phosphorus content of 600-20600 mg / kg, and establishing the matrix labeling standard curve by using XRF (X-Ray Fluorescence) intensity and phosphorus concentration; and XRF analysis: detecting the sample for 5 minutes under the conditions that the tube pressure is 10 kV, the tube flow is 100 [mu] A and the analysis spectral line is K alpha (2.010 keV), and calculating the phosphorus content according to the curve. Compared with traditional detection, detection can be completed only in 15 min based on XRF, and the speed is increased by 16-40 times. The pretreatment only needs water extraction, chemical reagents are avoided, the accuracy is remarkably improved by using a matrix standard curve, and the method is suitable for quality monitoring of frozen aquatic products.

Test the silica and phosphate content of a water sample in a single device. In this test method, a first sample of water is subjected to colorimetric analysis in a reaction chamber to perform a "molybdenum blue" test, in which the silica and phosphate in the sample complex with a first reagent. Then, a second reagent is used to make the phosphate complex optically inert, and a third reagent is used to deepen the color of the silica complex. Thereby, the silica content is calculated. Another sample is subjected to colorimetric analysis without using the second reagent to obtain the combined content of silica and phosphate in the said another sample. The value of the phosphate content of the sample is obtained by subtracting the value of the silica content from the value of the combined content of silica and phosphate. The silica content and phosphate content of the sample are reportable.

The application discloses a kind of total phosphorus and phosphate simultaneous automatic analysis system and device, belong to chemical analysis and quantitative technical field, for the simultaneous automatic determination of total phosphorus and phosphate content in water quality monitoring field and carry out relevant research.This application uses plunger pump to provide power for fluid, through the suction effect of plunger pump and three-way electromagnetic valve combination on-off electricity to realize the accurate quantification of reagent and sample volume;The pushing action of plunger pump sequentially injects different reagents and samples into the system flow path to produce color reaction and obtain response signal;During the heating digestion process of total phosphorus sample, the phosphate content in the sample can be determined simultaneously, which greatly reduces the overall analysis program time length;In addition, by changing the pushing speed of plunger pump, the retention time of reagent plug and sample plug in the system, i.e. reaction time, is adjusted, so that the effective detection range of total phosphorus and phosphate can be automatically switched.

The invention belongs to the technical field of filling mining, and particularly relates to phosphorite-based all-solid-waste synergistic filling slurry as well as an optimization method and application of the phosphorite-based all-solid-waste synergistic filling slurry. The optimization method comprises the following steps: mixing phosphogypsum, phosphorus slag powder and an alkali activator to obtain a cementing material; mixing the cementing material, the phosphate tailings and water according to different lime-sand ratios and mass concentrations to obtain different filling slurries, and respectively measuring the filling body strength, the slump, the diffusivity, the filling body leachate phosphate content, the filling body leachate fluoride content and the pH value of the different filling slurries; and constructing a mathematical function model, and solving optimal numerical values of the cement-sand ratio and the mass concentration under an optimization target and constraint conditions. The optimization method can reduce the filling cost on the premise of meeting the requirements of mine filling strength, fluidity and environmental protection.

Provided is a method of preparing a hydrogel composition including a uniform content of calcium phosphate, wherein a hydrogel composition prepared by the method has a uniform content of calcium phosphate, and thus may be used to quantify phosphates contained in the hydrogel composition. Provided is an in-vitro 3D osteoporosis model including a calcium phosphate hydrogel composition, wherein osteoblasts and osteoclasts may be three-dimensionally co-cultured inside a biogel, such that the osteoporosis model may be fabricated according to an intended use or clinical stage. Further, the model contains a calcium phosphate hydrogel with a uniform content of phosphate and thus enables quantification of calcium phosphate through measurement of phosphates, and therefore, the model may be used to screen candidate compounds for an osteoporosis drug and may effectively predict therapeutic effects of the drug on osteoporosis.

The application discloses a method for directional culture of diatoms by using aquaculture tail water and application, and belongs to the cross field of aquaculture and wastewater treatment. The method for directional culture of diatoms by using aquaculture tail water comprises the following steps: S1, precipitation: discharging the aquaculture tail water into a sedimentation tank to make silt and large particles precipitate; S2, sterilization and algae removal: sterilizing and removing original algae in the aquaculture tail water by irradiating the aquaculture tail water with ultraviolet rays; S3, nutrition structure adjustment: adjusting total salinity of the aquaculture tail water to be 20-30 ‰, adjusting silicate content to be 500-1000 micromoles / L, adjusting phosphate content to be 0.6-0.9 mg / L, and adjusting ammonium salt content to be 4-6 mg / L; and S4, inoculation of algal species and bacteria and culture: inoculating diatoms and diatom symbiotic bacteria into the aquaculture tail water. By using the method, directional regulation of a microalgal community in the aquaculture tail water can be realized, and the removal rate of nutrient salts in the aquaculture tail water and the resource recovery rate can be greatly improved. Meanwhile, byproduct shellfishes can be cultured and put on the market, economic benefits can be improved, and purification cost can be reduced.

The present disclosure discloses a process that determines the presence of phosphonate in saline water without specific equipment and can be used with simple resources if necessary. The process is carried out in two parts: 1) conversion of phosphonate by thermal method, and 2) determination of phosphate applying the analytical method based on digital images (DIA). Furthermore, the process for detecting phosphonates was developed with the concept of a portable analytical method capable of being performed even by analysts without training in chemical operations.

The utility model relates to a system for measuring the content of polyphosphate in a fertilizer. Comprising an elution unit and a compressed gas driving unit for controlling the elution unit, the elution unit comprises a plurality of pre-elution pieces which are connected in parallel, the tail ends of the pre-elution pieces are respectively connected with inlets of the ion exchange columns, and the tail ends of the ion exchange columns are connected with the collection part; the collection part comprises collection bottles in one-to-one correspondence with the pre-elution pieces; the compressed gas driving unit comprises a compressed gas part; the compressed gas part is respectively connected with a pneumatic valve assembly in the pre-elution piece and a pneumatic valve at the front part of the collection bottle through a gas compression pipeline; the device has the characteristics of reducing the requirement on the experience of operators, reducing the labor intensity, avoiding misoperation to the greatest extent, improving the detection efficiency and improving the accuracy of a detection result.

The present disclosure relates to a pharmaceutical composition for providing phosphorus to an adult or pediatric patient, wherein the composition is an aqueous solution of sodium glycerophosphate which by virtue of an improved process for producing the active pharmaceutical ingredient and the pharmaceutical composition is characterized by a low amount of free phosphate, a low amount of SGP-related substances and by a low amount of aluminum. The pharmaceutical composition is used in clinical nutrition, preferably in the preparation of nutritional formulations by compounding. The compositions can further be used for preventing or correcting phosphorus deficiency (hyperphosphatemia) in said adult or pediatric patients.

This invention relates to an apparatus and method for rapidly inhibiting nitrite-oxidizing bacteria to achieve deep nitrogen and phosphorus removal in urban wastewater, belonging to the field of biological wastewater treatment. The apparatus includes an influent reactor unit, an influent unit, an aeration unit, and an effluent unit. The method operates a short-cut nitrification / anaerobic ammonium oxidation system with low nitrogen and phosphorus removal efficiency due to the proliferation of nitrite-oxidizing bacteria in an anaerobic-aerobic-anoxic mode. By controlling the aerobic and anoxic time distributions, the nitrite accumulation rate in the aerobic section of the system is rapidly increased, reducing the total nitrogen and phosphate content in the effluent. This invention, by changing the operating mode, rapidly inhibits nitrite-oxidizing bacteria, improves the nitrogen and phosphorus removal efficiency of the short-cut nitrification / anaerobic ammonium oxidation system operating in an anaerobic-aerobic-anoxic mode, achieves deep nitrogen and phosphorus removal in urban wastewater with a low C / N ratio, and ensures stable operation. The operation and control are simple, requiring no external energy, thus saving energy and reducing consumption.

The application relates to the technical field of chemical analysis, in particular to a spectrophotometric determination method for phosphates in phosphorous acid, which comprises the following steps: adding a reducing agent to a sample to be measured to start a color reaction, synchronously triggering and performing double-wavelength high-frequency sampling, obtaining color light absorbance and background light absorbance at each moment during the whole determination process after the reaction is started; performing smoothing processing on the color light absorbance, evaluating the change degree of the smoothed color light absorbance with time to represent the time sequence characteristics of the change of the reaction rate, obtaining the relative change rate at each moment, and identifying the observation end moment when the main color reaction ends and the matrix interference drift starts; determining the interference drift rate, combining the reaction time, and determining the cumulative interference absorbance representing the matrix interference drift; obtaining the net absorbance, and determining the phosphate content in the sample to be measured. The application significantly improves the accuracy of the determination of trace phosphates in phosphorous acid.