https://www.selleckchem.com/pr....oducts/LAQ824(NVP-LA
This Letter extends the optical imaging from three- to four-dimensional information, which has an important scientific significance in both fundamental research and applied science.In the QCD axion dark matter scenario with postinflationary Peccei-Quinn symmetry breaking, the number density of axions, and hence the dark matter density, depends on the length of string per unit volume at cosmic time t, by convention written ζ/t^2. The expectation has been that the dimensionless parameter ζ tends to a constant ζ_0, a feature of