Biocrude yield and productivity from the hydrothermal liquefaction of marine and freshwater green macroalgae.

Six species of marine and freshwater green macroalgae were cultivated in outdoor tanks and subsequently converted to biocrude through hydrothermal liquefaction (HTL) in a batch reactor. The influence of the biochemical composition of biomass on biocrude yield and composition was assessed. The freshwater macroalgae Oedogonium afforded the highest biocrude yield of all six species at 26.2%, dry weight (dw). Derbesia (19.7%dw) produced the highest biocrude yield for the marine species followed by Ulva (18.7%dw). In contrast to significantly different yields across species, the biocrudes elemental profiles were remarkably similar with higher heating values of 33-34MJkg(-1). Biocrude productivity was highest for marine Derbesia (2.4gm(-2)d(-1)) and Ulva (2.1gm(-2)d(-1)), and for freshwater Oedogonium (1.3gm(-2)d(-1)). These species were therefore identified as suitable feedstocks for scale-up and further HTL studies based on biocrude productivity, as a function of biomass productivity and the yield of biomass conversion to biocrude.

Formate species in the low-temperature oxidation of dimethyl ether.

The oxidation of dimethyl ether (DME, 340 ppm in 10% O2) has been studied experimentally in an atmospheric pressure laminar flow reactor in the temperature range from 240 degrees C to 700 degrees C for residence times in the range 2-4 s. The influence of nitric oxide additions up to 620 ppm to the feed gases has also been investigated. Products of reaction were determined by FTIR. In the absence of NO, reaction is first detected at about 260 degrees C. The products in the low-temperature region include formaldehyde (HCHO), and formic acid (HCOOH). The addition of NO leads to the appearance of methyl formate (CH3OCHO). While the overall behaviour of the system can be explained qualitatively in terms of typical low-temperature hydrocarbon ignition, recently published chemical kinetic models for DME ignition do not allow for the formation of these formate species. We find no experimental evidence for the formation of hydroperoxymethyl formate (HPMF, HOOCH2OCHO) which is predicted by the models to be a significant stable intermediate at temperatures below 350 degrees C. Since both formic acid and methyl formate have potentially harmful health effects, these observations may have significant implications for use of DME as a diesel fuel.

The handicapped child at home.

The baby and small child are not able to perform consciously any adequate manoeuvres which will contribute positively to the correction of a disability. Thus the treatment of this age group is essentially passive or assistive active. Treatment attempting to achieve normal patterns of development is not a single "half hour period a day" approach but a "24 hour a day" plan of care and management. It is thus fundamental that success in treating the young child will depend on the child's parents and family. Since any child would be likely to spend most of the time with its mother, that child's future development is mostly in her hands, and any treatment of a child must be delegated very largely to the mother.