Transitions of laser diode(LD)pumped Er~(3+)-yb~(3+)co-doped glass laser are rather complicated.Consider- ing energy transfer between Er~(3+)and Yb(3+)ions,cros
In this paper, two different ring networks with unidirectional couplings and with bidirectional couplings were discussed by theoretical analysis. It was found t
The 20th APEC Economic Leaders’ Meeting yields fruitful results The 20th Economic Leaders’ Meeting of the Asia-Pacific Economic Cooperation(APEC) forum wrappe
Acacia karroo is an indigenous, strong drought-tolerant and widely planted tree in South Africa. In order to match the plant with its adaptation to forest sites