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This paper presents the results of spectral observations for the largest complete sample of very luminous IRAS galaxies obtained to date. The sample consists of those 73 objects for which ${\rm log}(L_{\rm IR}/L_{\odot}) \geq 11.5 $$(H_{0}=50\;{\rm km\; s^{-1} Mpc^{-1}} $, $ q_{0}=0.5) $and $\rm mag \leq 15.5 $, and was extracted from the 2 Jy IRAS redshift catalog. All the spectra were obtained using the 2.16 m telescope of Beijing Astronomical Observatory during the years 1994-1996. A total of 123 galaxy spectra were obtained with spectral ranges of $4400\;{\rm \AA} $to $7100\;{\rm \AA} $and $3500\;{\rm \AA} $to $8100\;{\rm \AA} $at resolutions of $11.2\;{\rm \AA} $and $9.3\;{\rm \AA} $respectively. In addition to the 73 spectra for sample galaxies, we also present spectra for ten non-sample galaxies and a further 40 for the companions of sample galaxies. The data presented include nuclear spectrum and the parameters describing the emission lines, absorption lines and continua as well as DSS images and environmental parameters.

Spectroscopic observations of a sample of 73 very luminous IRAS galaxies ($\rm log({\it L}_{IR}/{\it L}_{\odot})\ge11.5$for $\rm {\it H}_{0}=50~km\ s^{-1}\; Mpc^{-1}$,$\rm {\it q}_{0}=0.5$) from the 2 Jy redshift survey catalogue were carried out using the 2.16 m telescope at the Beijing Astronomical Observatory. The observational data, including the optical images (extracted from Digital Sky Survey) and spectra for these galaxies, are presented in Paper I (Wu et al. 1998). In this paper, we give the spectral and morphological classifications for these very luminous IRAS galaxies (VLIRGs). We show that about 60% of VLIRGs exhibit AGN-like spectra (Seyfert 1s, Seyfert 2s, LINER-like galaxies). This fraction goes up to 82% for the ultraluminous IRAS galaxies (ULIRGs) subsample ($\rm Log({\it L}_{IR}/{\it L}_{\odot}) \geq 12.0$). 56% of the VLIRGs show strong interaction or merging signatures; this fraction rises to 91% for the ULIRGs. These statistical results strongly suggest that interaction triggers nuclear activities and enhances the infrared luminosity. We find that LINER and a mixture type which have optical properties of both HII galaxies and LINERs could be at the transition stage from infrared luminous HII galaxies to AGNs; their main energy production is from starbursts as well as AGNs. Both infrared luminosities and $\rm H\alpha$equivalent widths increase dramatically as nuclear separations between VLIRGs and their nearest neighbors decrease. There is little doubt that strong starbursts happen in the nuclei of VLIRGs. Assuming class 0 as advanced merger, we construct a simple merger sequence, from morphological classes 1 to 4 (with near or far companions), to class 5 and 6 (interacting pairs and mergers) and then to class 0 (isolated galaxies). Along this sequence, VLIRGs evolve from HII galaxies to AGNs.

The leaching kinetics of vanadium from black shale under non-oxidative conditions was presented and compared with that under oxidative conditions. The effects of agitation speed, sulphuric acid concentration, temperature and particle size were determined. The morphology of the solid particles during leaching indicated that no product layer formed on the particles. The grain model with pore diffusion control provided a good description of vanadium leaching kinetics. The model gave an activation energy of 55·6 kJ mol-1, and reaction order 0·37 with respect to sulphuric acid due to diffusion and chemical reactions occurring in parallel in the porous solids. The linear relationship KD?1/r02found for the apparent rate constant, where r0is initial particle radius, also supported a diffusion controlled process. The apparent activation energy was 40% larger for leaching under non-oxidative conditions than for leaching under oxidative conditions, indicating that an oxidising atmosphere had a positive effect on vanadium leaching.

There are growing concerns about increasing emissions of greenhouse gases and a looming global warming crisis. CO2is a greenhouse gas that affects the climate of the earth. Fossil fuel consumption is the major source of anthropogenic CO2emissions. Chemical looping combustion (CLC) has been suggested as an energy‐efficient method for the capture of carbon dioxide from combustion. A chemical‐looping combustion system consists of a fuel reactor and an air reactor. The air reactor consists of a conventional circulating fluidized bed and the fuel reactor is a bubbling fluidized bed. The basic principle involves avoiding direct contact of air and fuel during the combustion. The oxygen is transferred by the oxygen carrier from the air to the fuel. The water in combustion products can be easily removed by condensation and pure carbon dioxide is obtained without any loss of energy for separation. With the improvement of numerical methods and more advanced hardware technology, the time required to run CFD (computational fluid dynamic) codes is decreasing. Hence, multiphase CFD‐based models for dealing with complex gas‐solid hydrodynamics and chemical reactions are becoming more accessible. To date, there are no reports in the literature concerning mathematical modeling of chemical‐looping combustion using FLUENT. In this work, the reaction kinetics models of the (CaSO4+ H2) fuel reactor is developed by means of the commercial code FLUENT. The effects of particle diameter, gas flow rate and bed temperature on chemical looping combustion performance are also studied. The results show that the high bed temperature, low gas flow rate and small particle size could enhance the CLC performance.

The large-scale structures of volume-limites subsample sorted out from the CfA catalog have been analysed by percolation method. The result shows that the features in the distribution of galaxies with different luminosities are significantly different. Especially, the most luminous galaxies are likely to exhibit hierarchical clustering on a scale about 50h50-1 Mpc, and the least luminous galaxies in our subsamples show string-like or sheet-like character in their distribution. These results suggest that the large-scale distribution of galaxies consists of clusters or cluster cores of most luminous galaxies and the less luminous galaxies spread out from these cores with a string-like or sheet-like structure. This picture of the large-scale distribution consists with previous results from two-point correlation analysis and fractal analysis. The implication of these results has been discussed.