Sample preparation, generally metal analysis

The first step in analysing plastics for metals content in polymers by ICP-AES technique is that they must be prepared in solutions that are suitable for nebulization. There are four general methods applicable for sample preparation for metal analysis by ICP-AES and they are solvent dissolution of some plastics dry ashing using a muffle furnace acid digestion using a microwave oven and oxygen bomb combustion. 

Applications Real applications of spark-source MS started on an empirical basis before fundamental insights were available. SSMS is now considered obsolete in many areas, but various unique applications for a variety of biological substances and metals are reported. Usually, each application requires specific sample preparation, sparking procedure and ion detection. SSMS is now used only in a few laboratories worldwide. Spark-source mass spectrometry is still attractive for certain applications (e.g. in the microelectronics industry). This is especially so when a multi-element survey analysis is required, for which the accuracy of the technique is sufficient (generally 15-30% with calibration or within an order of magnitude without). SSMS is considered to be a... 

To illustrate the feasibility of the proposed closed loop process, pure iron oxide FejOt was subjected to a producer gas from a 100 kW fluidised bed gasifier (reaction 1) and subsequently exposed to water vapour (reaction 2). For the reduction, Fej04 powder was placed in alumina cmcibles and heated in a tubular furnace at 900 °C and 1000 C, respectively while being exposed to a flow of producer gas for at least 25 minutes. The characterisation of the product by powder X-ray diffractometry and thermal analysis revealed that Fci. O indeed is the main product. Metallic iron and carbonaceous materials were identified as by- products. Generally, samples prepared at... 

Sample preparation of anaerobic adhesives for metal content is an important step, be it by destructive or non-destructive methods. Inactive metal salts are added directly to anaerobic formulations as fillers or for thixotropic reasons. Generally, active transition metals are not added directly to anaerobic adhesives but are prepared as activators in aerosol solvents to be applied to inactive surfaces as part B of an adhesive formulation. In the majority of cases trace metal analysis of anaerobic adhesives is only required for batches with problematic stability and is best done using destructive methods. 

The results obtained from the investigation of the crystallochemical properties of a family of mixed Li-vanadates of general formula LiCoyNi(i.y)V04 are reported. This kind of material is believed to be a valid alternative to the traditional positive electrode materials in the Li-ion cell, an electrochemical power source of outstanding importance in the portable electronics field. The powders, prepared via two different methods (a wet chemistry route and a solid state method), have been characterised by XRPD analysis, NMR and diffuse reflectance Vis-NIR spectroscopy. The findings allowed to correlate the electrochemical performance of the vanadates, which is higher for the samples prepared via wet chemistry, to the crystallinity of the powders and to the transition metal cations distribution. 

Qualitative analysis X-ray fluorescence is useful for elements with atomic numbers greater than 4, including metals and nonmetals. For qualitative analysis, no sample preparation is required and the method is generally nondestructive. 

Applications of ICP-MS cover a wide range of sample types which often make use of its excellent sensitivity and isotope ratio capabilities, such as the determination of ultra-low levels of impurities in semiconductors, long-lived radionuclides in the environment, and geochronology. ICP-MS is well suited to the determination of the lanthanide series of elements in many geological applications. Sample preparation methods are similar to those generally used for trace metals analysis however, nitric acid is favored for sample digestion because other mineral acids contain elements which cause spectroscopic in-teferences. 

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