Abstract:T he soil containing sulfate w as used to simulate saline soil environment ,and sulfate corrosion of concrete with fly ash or slag replacement and normal concrete for comparison were studied through half embedding in saline soil combining with sulfate solution wetting and drying cycles .With the proceeding of corrosion ,ultrasonic velocity ,macro‐and micro‐morphology and corrosion products of specimen concrete a‐bove and beneath soil interface were tested .The results show that the sulfate corrosion mechanism and cor‐rosion rate of concrete above and beneath soil interface in saline soil environment are obviously different . Corrosion of concrete above the soil interface belongs to physical crystallization corrosion ,and the corrosion products are sulfate crystallization .While corrosion of concrete beneath the soil interface belongs to chemi‐cal corrosion ,and the corrosion products are ettringite and gypsum .Corresponding different sulfate corro‐sion mechanisms ,effects of fly ash and slag are also different .The replacement of fly ash is not beneficial to the resistance of concrete sulfate physical crystallization corrosion ,w hile the replacement of slag is not beneficial to the resistance of concrete sulfate chemical corrosion .For the same kind of concrete ,the sulfate corrosion rate of concrete above the soil interface is significantly higher than that beneath the soil interface .

Abstract:A strain (DBP-WUST), which could highly utilize DBP as the sole carbon and energy source, was isolated from the active sludge in the refinery wastewater treatment plant of Sinopec Wuhan Petroleum Group Co. Ltd. According to the morphological observation, physiological and biochemical tests, and sequence analysis of 16S rDNA, the strain was identified as Elizabethkingia sp. The optimal temperature, initial pH, shaker rotary speed, and saturation inoculation dosage for strain DBP-WUST uti- lizing DBP was 35 ℃, pH7, 150 r/min and 7%, respectively. The experiments of DBP degradation by the pure culture showed that DBP of 400 mg/L could be degraded completely in 60 h under the optimal growth conditions. Furthermore, the COD of the waste-water could excellently be removed after the strain was added to the actual refinery waste-water.

Abstract:In order to improve the real‐time monitoring and control of the upper computer ,the commu‐nication is realized by PLC and CAN bus based on Modbus communication protocol .According to the moni‐toring interface of signal acquisition module ,the update rate of the information and the control effect of the upper computer to the output port module are realized .The communication protocol of Modbus and PLC is implemented in time ,which is based on CAN communication protocol .According to the experimental re‐sults ,the PLC and CAN bus communication are verified in time ,stability and efficiency .

Abstract:Dual System Estimator based on capture-recapture model is used to estimate the true popula-tion number for population. Here dual systems include census system and second census system that will be used to construct dual system estimator. It has type I and type II. Type I is its basic form with a rela- tively simple configuration. Type II, with its complex construction, takes full account of the migration ofpopulation between census and the second census, and is the advanced form of the dual system estimator.

Abstract:The differential settlement is a common issue occurring in the transition zone between bridg- es and embankments, which influences on the normal and safety operation of the railway. Based on the a nalysis of the harmfulness and the causes of the differential settlement between bridges and embankments, the improved requirements of the transition zone are summarized and the working mechanism of plate and geogrid is discussed qualitatively. A typical transition zone of Hanyi Railway Project in Tianmen is taken as an example. The relevant finite element model is established carefully, the working behavior of the transition zone treated by the combination of plate and geogrid is studied thoroughly using non-linear finite element method, the treatment effect is evaluated and the design parameter is also presented which can be taken as the reference in the practice.