The effect of hypochlorite concentration on Mycoplasma mycoides ssp. mycoides viability was tested under a variety of conditions. The experimental variables employed included chlorine-cell contact time, chlorine concentration, carrier system and organic loading. Initial populations of 106 c.f.u./ml were killed (no survivors in 1 ml) by hypoehlorite solution containing 25 p.p.m. available chlorine in 15 s in the absence of organic load and 50 p.p.m. available chlorine in 5 min in the presence of 1% protein. Higher concentrations of hypochlorite were required to disinfect a porous carrier system in the absence or presence of protein. The results are in contrast to previous reports that M. bovis is killed only by high hypochlorito concentrations.

Recent progress on the use of molecular engineering approaches for the enhancement and spectral tuning of the optical limiting responses of phthalocyanine complexes is presented. Examples are given involving the use of the heavy-atom approach to enhance the limiting response of naphthalocyanines and of donor substitution of naphthalocyanines to red shift the optical limiting response, as demonstrated for indium and tin octabutoxynaphthalocyanines. These approaches have led to new materials for optical limiting with potential for high performance. An experimental demonstration of the “bottleneck” limiter concept, in which the optical-limiting material is distributed nonhomogeneously to permit strong pumping of excited-state population throughout the interaction region, is presented and shows an order-of-magnitude increase in pulse suppression compared to a homogeneous distribution, without an increase in linear absorbance.

The performance of optical limiters depends on the ratio of the absorptive cross section for the transition from an excited state, σe , to that for transition from the ground state, σg . Both these factors depend on wavelength. It is appropriate to define two bandwidths, one for high energy pulse suppression, depending on σe , and the other for linear transmission, depending on σg . These bandwidths are affected differently by the use of molecular mixtures.