Vol. 80 0.70 g. was shown by infrared analysis to be the starting alcohol IX.The main fraction from the column was then dissolved in 13 ml. of 5% methanolic potassium hydroxide and boiled under reflux for 3 hours to effect hydrolysis. The solution was Rochester, N. Y.(18) K. Folkers and F. Koniuszy (U. S. Patent 2,370,651, March 6, 1945) give for dihydro-/?-erythroidine hydrobromide, m.p, 231-231.5°, ck25d + 107.5°(in water).

Greenhouse gases and cirrus clouds regulate outgoing longwave radiation (OLR) and cirrus cloud coverage is predicted to be sensitive to the ice fall speed which depends on ice crystal size. The higher the cirrus, the greater their impact is on OLR. Thus by changing ice crystal size in the coldest cirrus, OLR and climate might be modified. Fortunately the coldest cirrus have the highest ice supersaturation due to the dominance of homogeneous freezing nucleation. Seeding such cirrus with very efficient heterogeneous ice nuclei should produce larger ice crystals due to vapor competition effects, thus increasing OLR and surface cooling. Preliminary estimates of this global net cloud forcing are more negative than −2.8 W m −2 and could neutralize the radiative forcing due to a CO 2 doubling (3.7 W m −2 ). A potential delivery mechanism for the seeding material is already in place: the airline industry. Since seeding aerosol residence times in the troposphere are relatively short, the climate might return to its normal state within months after stopping the geoengineering experiment. The main known drawback to this approach is that it would not stop ocean acidification. It does not have many of the drawbacks that stratospheric injection of sulfur species has.

Publication InformationFinnegan, W,Goggins, J (2012) 'Numerical simulation of linear water waves and wave-structure interaction'. Ocean Engineering, 43 :23-31. Abstract:One of the main stages in the design of wave energy converters (WEC's) is the numerical modelling of a given converter. In this paper, the numerical simulation of both linear deep water waves and linear waves for the finite depth case are explored using computational fluid dynamics (CFD), to aid in this design stage. The CFD software package described in this paper is the commercial finite volume package ANSYS CFX (Release 12.1). The results of parametric studies, which were performed in order to optimise the CFD model, are detailed and a guide to creating a model that produces the desired waves is presented. The model was validated in two ways: (a) the wave created was compared to wavemaker theory (WMT) and (b) the water particle velocity and elevation of the wave was compared to linear, Airy, wave theory (LWT) for deep water waves. It was also found that wave generation in ANSYS CFX using a flap-type wavemaker was restricted to a low normalised wavenumber, k 0 h. In order to increase this restriction, the hinge of the wavemaker was raised and, with this alteration, it is possible to generate deep water linear waves. A case study of a real world application of wave-structure interaction, employing this methodology, is also explored.

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