About Some Question And Answer For QuEChERS
1. Why does the QuEChERS approach recommend use dry ice or liquid nitrogen homogenizing frozen samples and extracting samples while frozen?
The frozen samples were homogenized with dry ice or liquid nitrogen, and the samples were made into a fine powder (smaller particle size, more homogeneous), thus maximizing the extraction surface area and making the samples easier to process.
Samples should be extracted during freezing to prevent analyte degradation.
2. When I used the QuEChERS method to reconstruct the extract in LC/MS mobile phase solvent, precipitation would occur. How do I get over it?
If sediment is present during reconstruction, it can be ultrasonically treated and centrifuged to see if the sediment has entered the solution. If the recovery solvent is a percentage of methanol in water, first add methanol to dissolve the sample. Ultrasonic treatment and vortex before adding water.
3. Why wasn't the original QuEChERS approach buffered?
The non-buffered was developed for the analysis of fewer pesticides. The buffered is introduced, to apply to larger pesticide screen, and many compounds show pH dependence.
About Some Question And Answer For QuEChERS
Persona a contactar : Bruce Lu, +86 29 89284429
Buen trato: comprar del vendedor
Por favor, lea nuestras condiciones de uso. También puede visitar nuestras preguntas frecuentes y ver nuestra información sobre los riesgos relacionados con la falsificación.
Esta página es acerca de los importadores y exportadores de About Some Question And Answer For QuEChERS Buscar en la categoria : Bienes de equipo Buscar en la categoria : some, quechers, answer, about, question |
Viernes 08 marzo 2013
Cantidad : 10 - Precio : 80,00 €
Origen: China Número de modelo: V211141 Marca: Feature Anilutum: o: Material de los hombres: Estilo: camisa de manga larga en línea: 9AP-5PM Marca Anilutum delgado color sólido camisa de manga larga V211141 Aoniludan Anilutum para la marca de los hombres británicos de negocios...
H&Y International Fashion Limited
- anilutum
- EC1V 2NX - London
- +86 13724036041
Jueves 18 agosto 2016
Cantidad : 5000-1500 - Precio : 1200$/tns
Me nombro GBEDODJICHE DIDIER dueño de lasociedad Inter Africana AGRO-WORLD-IMPORT-EXPORT-TRADE Productor, Proveedor, Importación y exportación de los productos agrícola. tales-que: nuez de anacardo, madera, algodón, el arroz, maíz, judía, engrasa vegetal, guindilla,tomate, frutas...
AGRO-WORLD-IMPORT-EXPORT-TRADE
- 00229 - Cotonou
- +22 9 98 73 74 35
Sábado 20 febrero 2016
Precio : 2000 usd per mt CIF
We sell the best quality White and black pepper.We are selling for the cheapest CIF Prices. We are having free samples for quality testing For pepper, we now supply White and black pepper 500gl/ 550gl/ 570gl and white pepper 630gl Here are the specifications we offer: 1, Product Name...
Khun Jack Partnership Ltd
- 5000 - Chaing Mai
- +66 9 68 75 20 43