[en] Spectra obtained for the coma, nuclear fragments A and D, and tail of Comet West 1976 VI on April 1, 2 and 7, 1976 are noted to encompass coma spectra which differed from those of the nuclear fragments, which exhibited a strong continuum with superimposed emissions that included a stronger CO(+)-band system than that of the coma. A detailed comparison between fragment spectra has revealed great differences in both quasi-simultaneously obtained and five-day-separated cases. The relative intensities of different CO(+) bands are compared to the theoretical ones, and the abundances of CO(+) ions corresponding to different vibrational transitions are determined relative to that of CN. 24 references

[en] The standard nongravitation force model has been modified by allowing the water-vaproization curve to peak a certain number of days (DT) either before or after perihelion, and the modification is shown to often improve the data fit. The best fit to the astrometric data is generally achieved for a value of DT corresponding to the offset in the comet's visual light curve. The asymmetric model, which more accurately mimics the comet's outgassing history, suggests only weakly that the rotation direction of Comet Halley is direct, and it does not provide evidence that the rotation axis of Comet Kopff passed through its orbit plane in the early twentieth century. Approximate lag angles of 4 deg for Comet Halley and 10 deg for Comet d'Arrest are found using the asymmetric model, and it is noted that these values are lower than those obtained with the standard model. 34 refs

[en] Experimental studies of boiling in particle beds representing reactor core debris have been restricted to very small beds compared with those that may be found in a reactor. The use of air and water to simulate some of the many features of boiling in a particle bed has given results that were inconclusive. The work reported here is that carried out at Winfrith to extend the dryout data to larger particle diameters, and to provide new experimental data which removes earlier doubts, and makes the air-water analogue position much clearer. (U.K.)

[en] In a previous paper, a model was presented for the dissolution of a silicate glass under static conditions in a finite volume of water. In the present paper, this model is extended to describe dissolution in a finite volume of water which is replenished or through which there is a small flow. Dissolution equations appropriate to the model are derived and compared with experimental data for the dissolution of Vycor. The behaviour of the model is found to be consistent with the experimental results, and the dissolution parameters derived to be comparable with those found in previous static experiments. (author)

[en] In this paper, the effect of vertical walled obstacles on circular fronts propagating on the surface of shallow water is discussed. The amplitude of the transmitted acceleration waves is determined together with a recurrence relation for the reflection and transmission coefficients at successive obstacle walls. (author)

No abstract available

[en] High-resolution images of IRAS 09371 + 1212 in the J, H, and K bands show that this source is a small bipolar nebula viewed in the equatorial plane. A spectrum of this object in the 2.0-3.4 micron region shows a very narrow ice feature, interpreted as absorption by primarily pure crystalline water ice. 24 references

[en] Inverted annular flow was simulated adiabatically with turbulent water jets, issuing downward from large aspect ratio nozzles, enclosed in gas annuli. Velocities, diameters, and gas species were varied, and core jet length, shape, breakup mode, and dispersed core droplet sizes were recorded at approximately 750 data points. Inverted annular flow destabilization led to inverted slug flow at low relative velocities, and to dispersed droplet flow, core breakup length correlations were developed by extending work on free liquid jets to include this coaxial, jet disintegration phenomenon. The results show length dependence upon D/sub J/, Re/sub J/, We/sub J/, α, and We/sub G/,rel. Correlations for core shape, breakup mechanisms, and dispersed core droplet size were also developed, by extending the results of free jet stability, roll wave entrainment, and churn turbulent droplet stability studies

[en] The type of groundwater yielded from existing deep wells situated within 2Km from coastal line in U-do and Songsan area in classified as category 7, that is primarily salinity dominated by alkalies and strong acid such as saline water. The chlorine contents of the groundwater ranges from about 200ppm to 600 ppm. Tritium, deuterium, and oxygen-18 contents of seawater are 5.74±0.49TU, -4.6±1.2 o/oo, -0.8±0.02 o/oo in maximum, and 8.67±0.45TU, -24±0.18 o/oo, -3.61±0.12 o/oo in case of rainwater, and 15.11±0.61TU, -43.4±1.12 o/oo, -7.2±0.5 o/ oo in case of pure and not affected groundwater by salt water encroachment. In general the groundwater bodies being highly affected by salt water intrusion are characterized by that content of tritium is similar or quite same with one of the pure-nonaffected groundwater and contents of stable isotopes are higher than those. (Author)

[en] Widespread improvements in agricultural productivity have been achieved over the last century using a wide range of technological advances. Future improvements, however, are likely to be constrained by the decreasing quality of new lands brought into production, growing limitations on capital for crop expansion and mechanization, and increasing population pressures. On top of these constraints are new uncertainties about future climatic conditions and the effects of anthropogenic climatic changes on water availability. In order to better understand some of the impacts of climatic changes on food security, plausible changes in water supply are explored and the possible effects on food production investigated. The cases discussed here include increases and decreases in both the average and the variability of water resource availability. (author). 30 refs, 5 figs, 3 tabs