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The chitosan with the deacetylated degree 95%was mixed with the diatomite in the mass ratio of one chitosan to one point two diatomite to prepare the solid adsorbent for the sorption of the copper wastewater, which was based on the abilities of diatomite to adsorb cations and chitosan to chelate with metal ions. The absorbance of copper ions that were adsorbed before or after the adsorption can be measured at wavelength of 600nm by using spectrophotometer model 722, and both of the adsorption efficiency and capacity can be calculated then. The parameters to influence the adsorption of copper were studied under such conditions as different pH, concentrations, sizes, the sorption temperature and the sorption time. The results show that the adsorption efficiency can reach to 84.3% for 1L copper solution of concentration 0.8mol/L when 1g adsorbents are used at 27°C ,the value of the pH 6 and the sorption time for 1 hour. The cost of the adsorbent is low and it not only could be used to control the pollution of industrial copper wastewater but also provides references to the treatment of other heavy metal wastewater.

Steady sate flow of natural gas in buried pipeline is predicted with both the heat transfer between the flowing gas and the surrounding and the Joule-Thompson effect. The steady-state flow continuity, momentum and energy equations constitute the governing equations. As a constant gas mass flux (or gas mass flow rate) distribution along the pipeline is obtained from the steady-state continuity equation, the mathematical model describing steady-state gas flow in pipeline may be reduced to a second-order ODE system of first-order initial-value problem with gas pressure and temperature as the dependent variables. The forth-order Runge-Kutta method is used to solve this ODE system. Comparison between the predicted results and the observed field data are very good

This study focused on the distribution and pasting properties of starches in sweet potato (Ipomoea batatas L.) tuber. A fresh sweet potato tuber was cut into six equivalent parts. The extractable contents and pasting properties of starches from different parts of fresh sweet potato tuber were determined. The results showed that the extractable content of starches from the Middle section of sweet potato tuber is lower than that from the head and the end section of sweet potato tuber. The extractable content of starches from the inner-end part and the outer-Middle part of sweet potato tuber are 16.2% and 10.3% respectively. The amylose content of starches is relatively higher in the Middle section and outer layer of sweet potato tuber. The amylose content of starches from the outer-Middle part and the inner-end part of sweet potato tuber are 29.5% and 26.7% respectively. Pasting properties of starches from different parts of sweet potato tubers are different from each other. Among them, the starches from inner-end part of sweet potato tuber have the highest viscosities and a lower breakdown.

A species of derivatives of HBP-NH2 was synthesized from methyl acrylate, diethylene triamine and dodecylamine by two different modes (HSDA-1 and HSDA-2). Its molecular weight and possible structure were characterized by gel permeation chromatography, fourier transform infrared spectrophotometry and nuclear magnetic resonance spectroscopy. Dyed with reactive dyes, the cotton fabric which treated with the aqueous solution of HSDA displayed dramatically enhanced color strength, even when dyeing without electrolyte. It is concluded that the HSDA polymer can be used as a high direct staining salt-free auxiliary in reactive dyeing on cotton.

In the power system, out-of-step disconnection is the final defensive line of protection, requiring high reliability. This paper analyzed the physical meaning of out-of-step and the principles of disconnection to study the applicability of each discrimination method. It analyzed characteristics and variations of some parameters while oscillation or out-of-step, including impedance, frequency, cosine voltage, etc. It created relevant fuzzy functions and fuzzy rules with trapezoidal membership function based on the given characteristics and variations. Then a comprehensive out-of-step algorithm is achieved by integrating fuzzy functions together with given fuzzy rules. The output is defuzzied to be the final result with barycenter method to make decisions. This algorithm is tested to be more generic.