高水尘高压排风消声装置的研究

本文通过分析、论证、研究设计、对８－１８、９－１９风机的高水尘高压排风噪声的治理，提出了减压扩张声的净化水尘，消声降噪方案。经认真研究，实施应用于生产，大大净化了水尘、降低了噪声，消除了噪声对厂内外职工的干扰，取得了明显的环境效益和社会效益。而且该治理技术装置投资小，见效忆，施工方便，寿命长，清理维护与使用方便，消声量及水尘去除量大，属国内首创，具有一定的推广价值和发展前景。

Adsorption of Dye from Wastewater by Zeolites Synthesized from Fly Ash:Kinetic and Equilibrium Studies

The removal performance of a basic dye, methylene blue (MB), in aqueous solution was investigated by adsorption process on single-phase and high-crystalline zeolite A (FA-ZA) and X (FA-ZX). Both adsorbents FA-ZA and FA-ZX were synthesized from fly ash prepared aluminosilicate gel followed by the hydrothermal treatment at 100°C with the control of Si/Al molar ratio, respectively. The properties of the synthetic zeolites and commercial grade zeolites, such as thermal stability, elemental composition, and cation exchange capacity, were investigated for comparison. Batch method was used to study the influential parameters, such as initial pH value of the solution, temperatures, and adsorbents dosage, on the adsorption process. The experimental data were well fitted by Ho’ pseudo-second-order model and liquid film diffusion model. The suitability of Langmuir and Freundlich isotherms to the equilibrium data was investigated in the solid-liquid system while the Langmuir model produces the best re-sults. Thermodynamic data (△H, △S, and △G) corresponding to the MB uptake were evaluated from the Langmuir model. In all the adsorption experiments, the adsorption capacity followed the order as follows: FA-ZX > FA-ZA. In addition, attempts were also made to regenerate the adsorbents.

Research on rheological properties of micro-fine grouting cement

This article studies the influence of the fineness of cement, fly ash(FA), its composite admixture and the amount and way mixed with superplasticizer on the rheological properties of micro fine cement(MC). By means of modern instruments and technologies (such as XRD, SEM, laser granulometer and superficial potential apparatus etc.), the article studies the mineral compositions, the appearance character of grains, particle size distribution and superficial potential of FA and its composite materials. And through that, the reducing mechanism of FA is thoroughly analyzed. The study shows that FA and its composite admixture are excellent components which can effectively improve the rheological properties of micro fine cement, and that the superplasticizer has a saturation point and the mixing way of it has a great influence on the rheological properties.

Dust Diffusion Simulation in the Third Layer Construction of Underground Powerhouse

Under forced ventilation,the dust diffusion of underground powerhouse construction is investigated using a 3D high Reynolds number k-ε model.The interfacial momentum transfers and the wall roughness in the wall function are considered.Ventilation in the third layer of underground powerhouse of Xiangjiaba hydropower station is used as a case.The geometric structure has a decisive effect on the airflow distribution.It is concluded that the dust concentration decreases gradually with the increase of the ventilation time.However,iso-concentration curves have the same tendency after 1 800 s.The dust concentration meets the ventilation and dust-prevention health standard after 2 300 s.The prediction by the present model is confirmed by the experimental measurement by Nakayama.

Effect of Cement Dust Pollution on the Yield and Quality of Ficuscarica L. Fruits

The present study was carried out on Ficuscarica L. cultivated in the northwestern desert of Egypt. Plant materials （leaves and fruits） were collected from three polluted locations at a distance of 500-700, 1,000-1,250 and 3,000-3,500 m respectively away from the cement factory at EI-Hammam city, and a location of relatively clean air considered a control at 5,000-6,000 m away from this factory. The deposit cement dust washed from the surface leaf area of plant study was found to be 4.96, 4.21, 0.51 and 0.29 lag/cm2 at the four locations, respectively. Cement in more polluted locations increased mortality of young branches leading to a reduction in the height and yield of fig trees. The deposition of cement pollutants tothe loamy sandy soil of the present study alteredsoil chemical characteristics. The results showed that, biomass of fruits/tree, number of branches/tree and number of fruits/branch in polluted locations were significantly lower than those of the control one. Cement dust decreased leaf total chlorophyll content leading to a reduction in the economic yield （up to 50%）. Metabolic constituents （carbohydrates, proteins, amino acid and proline） and essential elements （Fe, Mg, Na, Ca, and K） were studied in two types of fruits on fig trees （mature and premature）. Thallium as a toxic metal was predicted in edible mature fruits, and the results showed that the concentration of thallium parts per billion （ppb） in polluted locations was significantly higher than those of the control one. The results revealed that fruits of fig plants at polluted sites showed quantitative and qualitative deteriorations.

亚洲上空的经声之旅[组诗]

走过瓦罕走廊十一把时光之篦，梳尽万山的寂静剩下这最后一个月的冰冷，铺满瓦罕走廊我的身影，被雪花推移着小心地印在这亚洲最远的天空之下群鸟飞逝。

Preparation and characteristics of a recycled cement-based superhydrophobic coating with dirt pickup resistance

We introduce a low-cost and effective technique that can transform waste cement-based dust into a superhydrophobic coating with dirt pickup resistance. An organic-inorganic hybrid superhydrophobic coating is prepared by the sol-gel method using methyltriethoxysilane as a precursor and waste cement-based dust as a film-forming material. Orthogonal experiments and a comprehensive scoring method were used to optimize the composition and production technologies. Our results show that this superhydrophobic organic-inorganic hybrid coating has an average static contact angle of 151.65° and low water adhesion. Related tests reveal that the dirt pickup resistance, washing resistance and film-substrate cohesion of this coating are also outstanding. The multi-scale physical and chemical mechanisms behind the properties of the coating are investigated. This recycled cement-based coating can be used as the external cover of engineering structures to protect them from corrosion.