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A series of char samples were derived from pyrolysis of two typical low-rank coals in China (Shengli lignite and Shenmu bituminous coal) at low, medium and fast heating rates, respectively, to the same pyrolysis temperature 750 °C. Then these chars were characterized by means of thermogravimetric analysis and Fourier transform infrared spectrometer with the aim to investigate the influence of heating rate in pyrolysis process on gasification reactivity and surface chemistry of them. Besides, a homogeneous model was used to quantitatively analyze the activation energy of gasification reaction. The results reveal that Shengli lignite and its derived chars behave higher gasification reactivity and have less content of oxygen functional groups than Shenmu coal and chars. Meanwhile, chars derived from Shengli lignite at 50 °C/min and Shenmu coal at 200 °C/min have the greatest gasification reactivity, respectively. The oxygen functional groups in Shengli lignite are easily thermo-decomposed, and they are less affected by the heating rate, while that in Shenmu coal have a significant change with the variation of heating rate. In addition, there is no good correlation between the change of oxygen functional groups and that of the gasification reactivity of the derived chars from pyrolysis at different heating rates.

Expansin proteins play a key role in inducing the extension and relaxation of plant cell walls. To understand the physiological role of expansins in lotus crop, Nelumbo nuciferaGaertn, during plant development, we cloned an expansin gene designated as NnEXPA1using the rapid amplification of cDNA ends technique. The full-length cDNA of NnEXPA1was 1,456 bp encoding a protein of 250 amino acids. Gene structure of NnEXPA1showed that it cosists of three exons and two introns. Phylogenetic tree and sequence analysis indicated that NnEXPA1belongs to theα-expansin subfamily. Results of the real-time semi-quantitative PCR demonstrated that NnEXPA1were difierentially expressed within all tissues except root during the plant development. Expression of NnEXPA1in leaf and rhizome were dramatically decreased during the initial to later stages of rhizome-development. In lotus root, however, NnEXPA1seemed to exhibit a stable expression pattern. Our results indicated that the transcript accumulation of NnEXPA1between the initial and early stages of rhizome development may be an important factor during rhizome size determination.

In this paper, on the basis of the working principles of high frequency ground wave radar for retrieval of ocean wave and sea wind elements were used to systematically study the data obtained from contrast validation test in Zhoushan sea area of Zhejiang Province on Oct. 2000, to validate the accuracy of OSMAR2000 for wave and wind parameters, and to analyze the possible error caused when using OSMAR2000 to retrieve ocean parameters.

Some important tidal features of 8 major tidal constituents (M2,S2,K1,O1,P1,Sa,N2andK2) in the China Seas and their adjacent sea areas were obtained using six years' TOPEX/POSEIDON altimeter data. The results showed that the obtained co-tidal and co-range charts for these major tidal constituents agreed well with those of previous researches using observational data from coastal tidal gauge stations and numerical models.

A combined numerical model of wind, wave, tide, and storm surges was built on the basis of the “wind field model in limited sea surface areas”. When used to forecast the sea surface wind, wave height and water level, it can describe them very well.

We use the separation of variable treatment to treat some time-dependent systems, and point out that the condition of separability is the same as the condition of existence of invariant, and the separation of variable treatment is interrelated with the quantum-invariant method and the propagator method. We directly use the separation of variable treatment to obtain the wavefunctions of the time-dependent Coulomb potential and the time-dependent Hulthén potential.