ALBERT

Description: Fifteen sandstone samples taken from pre-Cretaceous strata of the Yangtze Block are analysed to constrain the evolution of the South China Block, especially the assembly between the Yangtze and Cathaysia blocks. The results show that the maximum depositional age of the Neoproterozoic Lengjiaxi Group adjacent to the Cathaysia Block is c . 830 Ma, differing from that of the Kunyang and Dahongshan groups (〉 960 Ma) on the southwestern margin of the Yangtze Block. The detrital zircons from Palaeozoic samples from the Yangtze Block have similar age populations to those in the Cathaysia Block, and they may originate from the Cathaysia Block according to palaeogeographic, palaeocurrent and former research data. The detrital zircons of Middle–Upper Jurassic sandstones in the southwestern and central Yangtze Block yield dominant age populations at 2.0–1.7 Ga and subordinate groups of 2.6–2.4 Ga, 0.8–0.7 Ga and 0.6–0.4 Ga. The Upper Triassic strata may be derived from the southern Yangtze and North China blocks due to the collisions between the Indosina, South China and North China blocks, whereas the Jurassic sediments may be partly derived from uplift and erosion of the Jiangnan Orogen due to an intracontinental orogeny induced by Pacific subduction towards the Eurasia Plate. The detrital age spectra and provenance data for basement in the South China Block are analysed and compared with each other. The South China Block has affinity with Australia not only in the Columbia supercontinent but also in the Rodinia supercontinent. We infer the existence of an ancient orogen under the western Jiangnan Orogen, which may have occurred during the Columbia age, earlier than the Sibao orogeny. This is supported by seismic profile proof from the SinoProbe.

Description: SUMMARYCombustion of biogas containing hydrogen sulphide (H2S) yields highly corrosive sulphur oxides, thereby limiting the use of biogas for heat and power generation. The current study developed and tested a pilot-scale biogas bio-filter system (BBS) to replace conventional water scrubbing systems at a commercial pig farm in Miaoli County, Taiwan. A 62·8-litre pilot-scale BBS, packed with dried aerial roots from the common tree fern (Sphaeropteris lepifera) and a mixture of dried aerial roots and plastic rings as bio-carriers and inoculated with sulphur oxidizing bacteria, was installed at a commercial pig farm. H2S concentration was 5600 mg/m3 and the biogas flow rate was 4 litres/min. The pilot-scale BBS could remove 26·9 g H2S/m3/h using a bio-filter that operated at a 7% (v/v) O2 level continuously for 〉200 days. It was found that most H2S was oxidized to elemental sulphur (S0) and accumulated on the surface of the dried aerial roots (0·084 g S0/g aerial root) in the BBS. The dried aerial roots and plastic Raschig ring mixture was more efficent at sulphur dioxide removal than the dried aerial roots on their own. The pH and sulphate (SO42−) concentrations of water dropping from the BBS were 1·6 ± 1·0 and 28 680 ± 8253 mg/l, respectively. However, sulphur is the dominant product of sulphur oxidizers at the 7% O2 level. Periodical flushing of the bio-filter with the effluent from the wastewater treatment system on the farm can maintain high efficiency of H2S removal.

Description: The progress of leaf emergence, external morphology and apical development stages were recorded in sowings of triticale (cv. Lasko) made from February to November 1990 at Aberdeen (57° N). Leaf appearance and the number of primordia were related to thermal time (above a base of 0°C) except when photoperiods were