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A facile synthesis of rod-like alumina materials was developed through systematical investigation, which enables the control of the specific surface area of ammonium aluminium carbonate hydroxide (AACH) using aluminum nitrate as a precursor and urea as a precipitant. Our studies indicated that the molar ratio of CO(NH 2 ) 2 /Al influences crystallinity, morphology and the surface area of alumina materials. Amorphous alumina materials with nanorod morphology and high surface area (1029 m 2 g -1 ) was obtained with 15:1 M ratio of CO(NH 2 ) 2 to Al. In addition, the results demonstrated that thermal behaviors of the as-prepared AACH affect their crystallinities. Furthermore, the amorphous Al 2 O 3 prepared from AACH by calcination at 773 K was used as an adsorbent for Cr(VI) removal from water solution, and external factors were investigated, including contact time, adsorbent dosage, initial concentration of adsorbate and the pH of solution. It was found that the maximum adsorption capacity of prepared amorphous Al 2 O 3 for Cr(VI) was 52.1 mg g −1 , which was higher than those of other reported Al 2 O 3 samples.

A hybrid current drive scheme is investigated for its potential utilization with a tokamak reactor. In this scheme, the toroidal plasma current I P is maintained steady by the hybrid use of the tokamak transformer and non-inductive current drive (NICD). I P is driven by the inductive electric field E in the half-cycle of the high density burn phase of tokamak reactor. When the direction of E is reversed in the next half-cycle as in a.c. operation, the NICD power is applied to overcome the fact that the reversed E impedes I P and to maintain the direction and magnitude of I P as unchange. A small amount of NICD power is found to be necessary if n is decreased to a low level in this half-cycle. In this hybrid operation scheme, there are no problems of periodic ionization loss, breakdown and current ramp that is associated with a.c. operation scheme. Also, the requirement for transformer flux swing is found to be much lower than that in the a.c. scheme.