Narrow Results

A method has been proposed to reason the choice among the known optimized models for methods for estimating chlorophyll (Chl) concentration in the seawater according to the information-logarithmic criterion, which provides a comparison of theoretical models by the SeaWiFS data. It has been shown that the most appropriate means is to determine the Chl concentration, since the concentration of Chl in seawater is systematically investigated by marine ships or remote sensing. All optimized models of the optical properties of seawater can be verified by checking the simulated and measured Chl concentration data.

The influence of photodegradation on the optical limiting process of chloroform solutions of chlorophyll A is investigated. Optical limitation experiments were carried out with a frequency-doubled, 10 ns Nd:YAG laser at a 5 Hz repetition rate, as a function of sample degradation. Optical limitation becomes less effective in photodegraded samples, which may be explained by the decrease in the concentration of chlorophyll A molecules. It is concluded that the optical limiting process is mainly related to the reverse saturated absorption mechanism, and contributions from light scattering due to photodegradation and the cavity bubbles appear irrelevant.

This study investigates the effect of copper on the germination and growth of watermelon plants. It was found that copper only inhibited the germination and growth of watermelon plants when its concentrations were high. Copper concentrations of either 50 or 100μM increased chlorophyll content in the plants slightly while copper concentrations over 100μM led to an obvious decrease in chlorophyll contents. It is concluded that excess copper significantly affects the germination and growth of watermelon.