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A mathematical model was applied to falling film absorption outside the smooth and chute low-ribbed tubes to analyze the heat and mass transfer in the absorber. The liquid film outside tubes was assumed to consist of two layers, i.e., internal and external layers. A numerical calculation method was used to solve for the outer layer model of smooth tubes and the chute low-ribbed tubes. An analytical method was employed to solve for the velocity, temperature, and concentration in the internal layer of the tubes mentioned above. A second-order coupling method was adopted to couple the results of the two layers. It was shown that the agreement between the calculation results and the experimental data is high, with all errors assessed at less than 10%. The causes leading to the errors were analyzed. It was concluded that the chute low-ribbed tubes could serve as intensification tubes suitable for use in the absorber of lithium bromide absorption. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(1): 29–39, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20039

Scientific approaches to conservation of threatened species depend on a good understanding of the genetic information of wild and artificial population. The genetic diversity and structure analysis of 10 Eucommia ulmoides population was analyzed using inter-simple sequence repeat (ISSR) markers in this paper. A low genetic diversity at the population level (PPB=36.99%) and a high genetic diversity at the species level (PPB=85.54%) were revealed. Analysis of molecular variance (AMOVA) also detected a significant differentiation among the populations. Unweighted pair-group method with arithmetic averaging (UPGMA) clustered the 10 population into 3 groups, and no significant correlation was found between the genetic distance and the corresponding geographic distance among the populations, which is consistent with the results of principal coordinate analysis (PCoA). The genetic variation between the artificial and wild populations revealed a decreased genetic diversity and aggravated genetic differentiation in the artificial populations. A conservation strategy of Eucommia ulmoides is discussed based on the information of the population genetic structure and variation. Key words : Eucommia ulmoides , inter-simple sequence repeat (ISSR), genetic diversity, genetic structure, conservation.

AM-In order to research gastric motility information, a new collection system base on ADuC834 was designed. ADuC834 was selected to collect the low-frequency gastric impedance signal. The filter circuit was simple and only got rid of the interference of EMG and ECG. The software base on wavelet transform assumed all signals processing work. The gastric motility information can be observed in this study. We can research gastric motility situation according to the signal extracted by ADuC834 and wavelet transform. ADuC834 is suitable for extracting the low frequency gastric impedance signal and can further simplify the hardware configuration. All useful gastric motility information can pass through the simple filter circuit. Wavelet transform have good performance to get rid of the interference. Experiments have proved that the system base on ADuC834 is feasible and a reliable collection system is provided to research gastric motility information.