5results about "Nitrogen determination" patented technology

The application belongs to the technical field of food safety, and particularly relates to a volatile organic compound detection device based on olfactory visualization technology and a detection method thereof. The device comprises a fixed frame structure, a control module is arranged above the fixed frame structure, a detection platform is arranged below the fixed frame structure, a pipette and an image acquisition device and a sensor control device are respectively arranged above both sides of the detection platform, and the control module is connected with the pipette, the image acquisition device and the sensor control device. The control module is used for controlling the pipette, the image acquisition device and the sensor control device to operate in the detection platform area. The application can prepare a color-sensitive sensor printed with a metal porphyrin, obtain volatile gas of an organic compound, and cause a coordination reaction with the volatile gas. Image data before and after the reaction of the volatile gas with the organic compound is detected and analyzed through the image acquisition device, and corresponding chemometrics methods are combined, so that rapid quantitative analysis of the organic gas can be realized.

The invention relates to the technical field of grassland planting, and discloses a saline-alkali soil mixed sowing grassland improved planting method, which comprises the following steps: collecting soil samples of different areas of saline-alkali soil, marking information, detecting indexes such as salinity and pH value, and removing abnormal data to obtain soil basic data; preparing a regulating embedding medium, and preparing a growth zone substrate; then delimiting leguminous and gramineous growth zones according to soil and terrains, filling a matrix, and mixing, sowing and compacting; then erecting an irrigation pipe, alternately irrigating fresh water and salt water, trickle-irrigating corresponding bacterial liquid, and preserving moisture to promote field planting; and finally, setting a mowing rotation rest period, regularly rechecking soil and grassland conditions, and adjusting parameter circulation until an improvement target is achieved. The improvement efficiency of the saline-alkali soil and the sustainability of mixed sowing grassland are greatly improved, and the improvement requirements of areas with different terrains and saline-alkali grades are met.

The invention discloses a multi-element type soil nutrient prediction method coupling multi-source covariables and an in-situ spectrum. The method comprises the following steps: step 1, soil in-situ hyperspectral measurement and data acquisition; 2, collecting and preparing a soil sample; step 3, acquiring covariable data; step 4, acquiring soil nutrient data; step 5, in-situ spectrum data pretreatment: carrying out pretreatment operation on the soil in-situ spectrum; step 6, detecting and eliminating abnormal values of the spectral data; step 7, feature dimension reduction and screening; 8, constructing a multi-target regression prediction model of the soil nutrient content; step 9, model prediction performance evaluation and comparison; and step 10, quantifying the contribution of the multi-source covariable in model prediction. The method provided by the invention overcomes the defects of large prediction deviation and weak generalization ability caused by multi-element soil and multi-target nutrient modeling in the prior art, and can realize efficient, lossless and accurate prediction of the total nutrient content and the effective nutrient content of the multi-element soil under the provincial scale.

The invention discloses a deep soil nitrogen content monitoring method, a server and a storage medium, and belongs to the field of soil component monitoring, and the method comprises the following steps: obtaining remote sensing image data of surface soil of a soil sampling point, and collecting a soil sample of the corresponding soil sampling point; performing preprocessing, spectral transformation and spectral feature extraction on the remote sensing image data, and constructing a multi-dimensional feature space; analyzing the corresponding soil sample to obtain a change rule of surface nitrogen and deep nitrogen, and obtaining a surface-deep nitrogen relation model; screening a characteristic wave band combination of which the correlation with the surface nitrogen content exceeds a threshold value from the multi-dimensional characteristic space, and establishing a surface nitrogen content inversion model; in the actual use process, after remote sensing image data are collected, the nitrogen content of deep soil is monitored through the surface layer nitrogen content inversion model and the surface layer-deep layer nitrogen element relation model. The method avoids the problems of high cost and low timeliness of traditional sampling analysis.

The invention discloses a method for determining the nitrogen index of protein in milk powder and application, and the method comprises the following steps: taking a milk sample, and dissolving in water to obtain an emulsion; adjusting the pH value of the emulsion to precipitate casein and denatured whey protein, and filtering to obtain a filtrate A; determining the nitrogen content in the filtrate A; mixing the filtrate A with a trichloroacetic acid solution to precipitate undenatured whey protein, and filtering to obtain filtrate B; determining the nitrogen content in the filtrate B; the difference value between the nitrogen content in the filtrate A and the nitrogen content in the filtrate B is the nitrogen content of the undenatured whey protein in the milk powder. The determination method disclosed by the invention has the characteristics of high universality, precision, accuracy, operability and the like, and provides a technical basis for determining the denaturation degree of the whey protein in the milk powder.