Toward the Atomic-Level Mass Analysis of Biomolecules by the Scanning Atom Probe

In 1994, a new type of atom probe instrument, named the scanning atom probe (SAP), was proposed. The unique feature of the SAP is the introduction of a small extraction electrode, which scans over a specimen surface and confines the high field, required for field evaporation of surface atoms in a small space, between the specimen and the electrode. Thus, the SAP does not require a sharp specimen tip. This indicates that the SAP can mass analyze the specimens which are difficult to form in a sharp tip, such as organic materials and biomolecules. Clean single wall carbon nanotubes (CNT), made by high-pressure carbon monoxide process are found to be the best substrates for biomolecules. Various amino acids and dipeptide biomolecules were successfully mass analyzed, revealing characteristic clusters formed by strongly bound atoms in the specimens. The mass analysis indicates that SAP analysis of biomolecules is not only qualitative, but also quantitative.

Research and Industry Application of New Process of Low Copper Oxide Ore

The experiments of refractory copper oxide ore which comes from Tangdan of Yunnan Province were studied in laboratory using bulk flotation process and a new process that Ammonia leaching-Extraction-Electrode position-Residue flotation under normal temperature and pressure respectively. The results show that new process, compared with bulk flotation, had an effect to add 10.8 percent points to recovery. And then it is confirmed by industry experiment. So it is successfully applied to industry production and technology indicators were improved dramatically.