12 results about "Atomic absorption spectroscopy" patented technology

The invention discloses a rapid enrichment-atomic absorption spectrum analysis method for low-content gold in gold ore, and relates to the technical field of gold ore analysis and detection.The rapid enrichment-atomic absorption spectrum analysis method comprises the following steps that an ore sample and a solid composite additive are mixed and roasted at the low temperature of 500-650 DEG C, and the additive contains alkali metal carbonate and zinc oxide; sulfur fixation, catalytic oxidation of organic carbon and stabilization of volatile elements can be synchronously realized; the method comprises the following steps: roasting gold-loaded activated carbon, dissolving the gold-loaded activated carbon in aqua regia to obtain a to-be-enriched solution, enabling the solution to pass through an adsorption column filled with modified activated carbon, pretreating the activated carbon with a 1-10% ammonium citrate solution to improve the selective adsorption capacity of the activated carbon on gold chloride complex ions, ashing the gold-loaded activated carbon, dissolving residues, fixing the volume, and measuring by using an atomic absorption spectrometry. According to the rapid enrichment-atomic absorption spectrum analysis method for the low-content gold in the gold ore, through cooperation of low-temperature roasting of the composite additive and selective adsorption of the modified activated carbon, the decomposition efficiency and enrichment selectivity of the ore difficult to treat are improved.

This invention provides a method and apparatus for lithium recovery from a high-sodium, low-lithium solution via cryogenic sodium precipitation and targeted extraction. The method comprises the following steps: S1, weighing sodium sulfate and lithium sulfate samples, dissolving them in deionized water to prepare a high-sodium, low-lithium solution; S2, determining the lithium and sodium ion content of the high-sodium, low-lithium solution using ICP-MS and atomic absorption spectroscopy; S3, freezing the high-sodium, low-lithium solution prepared in step S1 in a circulating freezer to obtain a solid-liquid mixture. The method and apparatus provided by this invention achieve low lithium carryover during sodium precipitation from a high-sodium, low-lithium solution, further realizing high-efficiency lithium resource recovery. Compared with traditional processes, the lithium carryover rate during sodium precipitation can be reduced to 0.2%, reducing energy consumption and operational difficulty while improving lithium recovery rate, making it suitable for industrial production.

The invention relates to the technical field of mineral analysis, in particular to a method for determining the content of valuable elements in an indissolvable mineral product based on high-pressure closed digestion and atomic absorption spectrometry. Mixed acid serves as a digestion system, constant-temperature closed digestion is conducted only after acid is added once, then analysis is conducted through an atomic absorption spectrometer, and the content of the valuable elements in the indissolvable mineral product is obtained. By combining an absorbance standard curve, high-accuracy detection on the content of the value elements in the insoluble mineral product can be realized, and content analysis on various value elements in the insoluble mineral product can be carried out.

The application provides a method for jointly measuring gold and silver in smelting fumes, which adopts a fire assaying method to enrich gold and silver in the sample, and a large part of silver in the obtained gold-silver combined particle is dissolved by using a nitric acid solution, after filtration, gold in the filter residue is dissolved by using aqua regia, after silver chloride is precipitated and separated from gold and silver again, the remaining small amount of silver in the filter residue is dissolved, the segmented digestion method prevents "passivation" of silver in the combined particle when the aqua regia directly dissolves the silver, and ensures that the gold and silver in the combined particle are completely dissolved into the solution, and then atomic absorption spectrometry is adopted to jointly measure the gold and silver, compared with the existing gold-silver separate measurement method of measuring gold by the fire assaying method and measuring silver by the atomic absorption spectrometry, the detection process is shortened and the detection efficiency is improved, and therefore the method has a certain application prospect.

The invention provides a method for simultaneously detecting gold and silver in smelting smoke dust, which comprises the following steps of: enriching gold and silver in a sample by adopting a fire assaying method, dissolving most of silver in obtained gold-silver particles by using a nitric acid solution, filtering, dissolving gold in filter residues by using aqua regia, filtering silver chloride again, precipitating and separating the gold and the silver, and detecting the content of the silver in the gold-silver particles. According to the sectional digestion mode, the situation that the silver in the combined particles is directly dissolved by the aqua regia to cause passivation is prevented, it is guaranteed that the gold and the silver in the combined particles are completely dissolved into the solution, and then the gold and the silver are jointly measured through the atomic absorption spectrometry. Compared with an existing gold and silver separate detection mode for detecting gold through a fire assaying method and silver through an atomic absorption spectrometry method, the detection process is shortened, the detection efficiency is improved, and therefore the method has a certain application prospect.

The invention belongs to the technical field of atomic spectrum analysis, and particularly relates to an analysis technology for measuring trace cadmium in a complex sample based on a cold atom absorption spectrometry, in particular to a cold atom absorption spectrometry for measuring trace cadmium by taking water as a carrier current. According to the method for measuring the trace cadmium based on the cold atomic absorption spectrometry, a chemical atomizer can be connected to any flame atomic absorption instrument, then the content of the trace cadmium element in various complex matrixes is measured by adopting a cold absorption method under high acidity by taking water as a carrier current, the detection limit of the method is equivalent to that of ICP-MS, and the method has the advantages that the method is simple and convenient to operate, and the method is suitable for large-scale popularization and application. The method has the advantages of simple and fast operation, low consumption and high sensitivity.

Provided is a thermally conductive silicone composition capable of both satisfying weight reduction and storage stability even when an aluminum hydroxide filler is used. The thermally conductive silicone composition includes: (A) a diorganopolysiloxane containing an alkenyl group bonded to a silicon atom; (B) an organopolysiloxane having a hydrogen atom bonded to a silicon atom; (C) a first thermally conductive filler contained in an amount of 30 parts by mass or more and 220 parts by mass or less relative to 100 parts by mass of the total amount of the component (A) and the component (B), the first thermally conductive filler being at least one thermally conductive filler selected from the group consisting of aluminum oxide (C1) that contains less than 300 ppm of hot water-extractable sodium oxide, as determined by atomic absorption spectrometry, and that has an average particle diameter of less than 5 μm, and aluminum hydroxide (C2) that contains less than 70 ppm of hot water-extractable sodium oxide, as determined by atomic absorption spectrometry, and that has an average particle diameter of less than 5 μm; and (D) a second thermally conductive filler contained in an amount of 400 parts by mass or more and 950 parts by mass or less relative to 100 parts by mass of the total amount of the component (A) and the component (B), the second thermally conductive filler being an aluminum hydroxide filler that contains less than 70 ppm of hot water-extractable sodium oxide, as determined by atomic absorption spectrometry, and that has an average particle diameter of 5 μm or more and 100 μm or less; and (E) an addition reaction catalyst contained in an amount of 0.2 parts by mass or more and 1.0 part by mass or less relative to 100 parts by mass of the total amount of the component (A) and the component (B).

The invention belongs to the technical field of atomic absorption spectrometry analysis, and particularly relates to a method for rapidly determining trace Pb in a complex sample under high acidity based on atomic absorption spectrometry, in particular to an analysis method for accurately and rapidly determining trace Pb in cosmetics. According to the method for rapidly determining the trace Pb in the complex sample under the high acidity based on the atomic absorption spectrometry, the HCl concentration of a test system can be greatly improved to 10% by adopting a designed chemical atomizer and optimizing the conditions of reduction reaction; the method breaks through the bottleneck that trace Pb in a few simple samples can only be measured under low acidity by a hydride generation method, so that the chemical reaction of Pb and NaBH4 can be stably carried out under high acidity, the problem of testing trace Pb in complex samples is solved, and the method is high in sensitivity, simple and rapid to operate and reliable in test result.

The invention belongs to the technical field of atomic spectrum analysis and detection, and particularly relates to a method for separating trace Se and As in a multi-metal sample and a method for rapidly detecting the trace Se and As in the multi-metal sample based on atomic absorption spectrometry. According to the method for separating trace Se and As in the multi-metal sample, a miniature cation chromatographic column is adopted, especially a zero empty bed volume leaching technology is adopted, the column flow rate can be as high as several milliliters per minute, the elution volume is only 1-2 milliliters, the separation effect is close to 100%, only 2-3 minutes are needed for collecting As or Se flowing through a column bed, the separation speed is high, and the separation efficiency is high. And the determination result is accurate and reliable.

A neurosurgery system for resecting tissue after administration of a contrast agent to a patient, the system including an electrosurgical instrument for manipulating tissue which generates a fluid sample from the tissue during ablation, an aspiration channel configured to obtain the fluid sample, an analyzer for analyzing the fluid sample, an indicator configured to provide an indication of the presence of a rare earth metal, and a controller configured to instruct the indicator to provide the indication of the presence of the rare earth metal. The analyzer includes a collector coupled to the aspiration channel and configured to receive a portion of the fluid sample from the aspiration channel, a heater configured to atomize the portion of the fluid sample, and a detector configured to measure an absorption of a wavelength corresponding to a rare earth metal.

The invention discloses a total analysis method for carrying out pretreatment-colorimetric intelligent detection on total copper in urine and water, which is a method for simultaneously carrying out pretreatment and colorimetric detection on a water sample on test paper by loading different active materials in different areas of a polymer fiber membrane on the basis of a partitioned bifunctional polymer fiber preparation technology. And tedious metal ion detection steps based on large instruments (atomic absorption spectrum and inductively coupled plasma mass spectrum) are simplified. And total copper in water is degraded through photocatalysis to release free copper ions, and free copper enters a lower layer to be reduced by a reducing agent and is chelated by a color developing agent to display a color signal corresponding to the concentration. A DCNN model is adopted to replace a traditional colorimetric card detection method, background interference and light environment noise can be effectively removed, and the effective detection range is 1.00-200.00 [mu] mol / L after multiple times of training and learning. And an APP is carried, so that a total analysis and detection system for total copper in water, which integrates rapid sampling, convenient pretreatment, rapid detection and real-time visual detection, is formed.

The present application relates to the technical field of environmental monitoring, and provides a method for determining chromic acid mist in waste gas, comprising: collecting a chromic acid mist sample in waste gas to obtain a sample carrier; extracting and treating the sample carrier by using an aqueous solvent to obtain a sample solution; determining the chromium content in the sample solution by using atomic absorption spectrophotometry; and calculating the concentration of the chromic acid mist in waste gas based on the chromium content. The present application discards unstable color reaction steps, effectively shields the interference of coexisting ions by using the high selectivity of atomic absorption spectroscopy, significantly improves the accuracy, stability and operation simplicity of determination, and reduces the detection cost.