Pesticide reference material research and drug analysis: expanding the production and usage of pesticides, pesticide reference materials played an important role in monitoring quality control and pesticide residues of pesticide. Subject to the present analysis method were optimized six kinds of pesticides and verification methodology, these pesticides established GC / MS and HPLC qualitative analysis quantitative analysis. The characteristic ions were obtained based on the GC/MS results , confirming the molecular structure of the six pesticides. Selection ZORBAXSB-C18 column was analyzed, to DAD detector, six kinds of pesticides are linear range between 0.1-50 μ g.mL-1, a good linear correlation, the correlation coefficient R values are greater than 0.998, the lowest quantification limit between 0.1-0.2 μ g.mL-1. According to the standard material development methods and procedures , six pesticide reference materials were developed using various purification methods and analytical techniques. These six standard substances uniformity test, stability test, analysis of the sources of uncertainty, so that its final value. The results show that the analytical method is reasonable , and the six pesticide standard materials developed have good uniformity, and the stability period is more than one year , which meets the requirements for the development of national secondary standard materials. Drug analysis plays an active and effective role in the quality control and monitoring of drugs.
A good Bi-metal Hole Saw will cuts faster and smoother and with reduced vibration due to the variable pitched teeth, hole saws have two different types of steel joined together to form the edge of the cutting end of the Hole Saw. High speed steel is joined to a soft spring steel to form a durable edge that will cut a multitude of materials and help provide long life. High speed steel is used on the outer edge due to its wear resistance properties and forms the cutting edge of the teeth. Soft, spring steel creates a flexible backing material that allows the hole saw to absorb impacts of the job of drilling holes in difficult-to-cut materials.
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