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Edible seaweed consumption is an essential route of human exposure to complex organoarsenicals, including arsenosugars and arsenosugar phospholipids. However, the effects of gut microbiota on the metabolism and bioavailability of arsenosugars in vivoare unknown. Herein, two nori and two kelp samples with phosphate arsenosugar and sulfonate arsenosugar, respectively, as the predominant arsenic species, were administered to normal mice and gut microbiota-disrupted mice treated with the broad-spectrum antibiotic cefoperazone for 4 weeks. Following exposure, the community structures of the gut microbiota, total arsenic concentrations, and arsenic species in excreta and tissues were analyzed. Total arsenic excreted in feces and urine did not differ significantly between normal and antibiotic-treated mice fed with kelp samples. However, the total urinary arsenic of normal mice fed with nori samples was significantly higher (p< 0.05) (urinary arsenic excretion factor, 34–38 vs 5–7%), and the fecal total arsenic was significantly lower than in antibiotic-treated mice. Arsenic speciation analysis revealed that most phosphate arsenosugars in nori were converted to arsenobetaine (53.5–74.5%) when passing through the gastrointestinal tract, whereas a large portion of sulfonate arsenosugar in kelp was resistant to speciation changes and was excreted in feces intact (64.1–64.5%). Normal mice exhibited greater oral bioavailability of phosphate arsenosugar from nori than sulfonate arsenosugar from kelp (34–38 vs 6–9%). Our work provides insights into organoarsenical metabolism and their bioavailability in the mammalian gut.

In order to overcome deterioration of heat transfer caused by two-phase flow and avoid flow separation, using volume expanding evaporator instead of steam-water separator to make integration and optimization between parabolic trough solar energy collection system and coal-fired power plant regenerative heating system. Then based on equivalent enthalpy drop method, it analyses the thermal economy about 300MW coal-fired unit to discuss the optimal integration solutions and works out the unit thermal economy variation tendency and the best back water position of the drain in volume expanding evaporator when the different stage extraction steam of coal-fired unit replaced by the exit steam of solar collection system super heater region. The results show that the whole third stage extraction steam replaced by solar heat and drain water in volume expanding evaporator returned back to 3 heater exit of coal-fired unit feedwater pipeline is the best scheme.

The exhaust steam heat of steam driven feed pump small steam turbine is considerable in modern coal-fired power generating unit, most of which is adopted the way of wet cooling through the condenser as same as main steam turbine for condensing steam turbine unit, all the waste heat with it is taken away by circulating cooling water and not used effectively. This paper will propose the way of part of exhausted steam of small steam turbine recycled to the regenerative extraction steam system to heat condensate based on steam ejector heat pump, so as to use the exhausted steam effectively and analyze the thermal economic index of different schemes by using equivalent enthalpy drop method. The results show that it produces best economic benefits when exit steam of steam ejector heat pump is recycled to steam extraction of the fourth section.

Using a CFD software, the numerical simulation of a 2×300MW direct air-cooled unit is done by multi-stage modeling method. the effect of the environmental wind on the heat-exchanging performance of the air-cooling island is analyzed by numerical simulation. The effects of different wind velocities and directions on exterior flow field and heat-exchanging efficiency are analyzed. The reasons of hot air recirculation and the decrease of the fans’ output are found. The heat transfer performance of air-cooled island is affected after the installation of windproof net. The result shows that the form of low-pressure area is the main reason for the hot air reflow and the decreace of the fan’s output; An improved flow field can be got after installing the windproof net. The volumetric effectiveness can be increased by 8.5% at a wind speed of 9 m/s.

In order to study characteristics of loads on a cutting drum of a continuous miner, a mathematic model of random loads on the drum is set up in the paper by means of defining probability distributions of three-direction loads, loads and their variations on a cutting drum are given by building a computer simulation program when it cuts pure coal, rock and hard parcel. Results show that swing resistance is the greatest, forward resistance is the second, axial resistance is the least; a cutting resistance torque increases with the increase of broken media strength; loads cut stone layer are much larger than pure coal; range of load change and load fluctuations are big as cutting hard parcel, these conclusions are correspond with the actual situation.

Influencing rules of surface roughness for the work-piece by changing major milling parameters are studied when 2A70 alloy are cut by cemented carbide ball-end milling cutter cuts in high-speed. Primary and secondary influence order of test factors are found out through range analysis and variance analysis of test data according to the orthogonal test designed by the manufacture experience. Influencing tendency between milling parameters such as feed per tooth, back cutting depth, milling speed and line width and the roughness are obtained, a prediction model of aluminum alloy surface roughness is built up, surface quality of the product can be predicted and productivity can be analyzed.

A spiral drum is a important cutting mechanism, and its design quality has important effect on the machine service life, volume of the coal block and breast conditions. By analysis and study of the key technology on the expert system and reference to expert experience and design examples, the expert system of shearer drums is found bottom-up upper based on VB6.0 programming platform and adopted modular design method. It is quickly designed and simulated for the spiral drum structure by using the expert system, which improves design qualities and efficiencies on shearer drum and lays a foundation for the designing high quality shearer.