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Ti–NiCrAl coating was fabricated on the substrate of Ti6Al4V alloy by laser cladding (LC), in which the Ti originated from the diluted element of substrate. The results show the Ti–NiCrAl coating is composed of NiTi and NiTi2 phases with the trace CrO and Al2O3 phases, in which the oxide phases are acted as an effective barrier to provide high-temperature protection for the substrate. The coefficient of friction (COF) and wear rate of Ti–NiCrAl coating are decreased with the elevated temperatures, which is attributed to the phase transformation of NiTi and NiTi2. The wear mechanism is the combination of abrasive wear and adhesive wear, in which the phase transformation of NiTi and NiTi2 phases play the roles of friction reduction and wear resistance. [ABSTRACT FROM AUTHOR]

The year 1998 was an unusual year for Guangdong Province and Hong Kong, both in southern China, as the frequency and intensity of harmful algal blooms (HAB) were much higher than usual. This paper describes the causative organisms found associated with these blooms and speculates on the possible causes of these blooms, including the effects of increased temperature, reduced salinity, eutrophication and meteorological and oceanographic events on the initiation and spread of these blooms. [ABSTRACT FROM AUTHOR]