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51.
内循环好氧三相流化床处理造纸中段废水 总被引:6,自引:0,他引:6
本实验采用内循环好氧三相流化床处造纸中段废水,经过一段时间的驯化,获得了稳定的出水。CDO去除经保持在65%以上,系统对进水污染负荷的变化具有较大的承受能力。出水Cl^-的浓度有所增加,说明驯化后的微生物可能对有抽氯化物具有一定的降解作用。水气比在1/120至1/140之间可获得最好的COD去除效果。后进行絮凝处理后,出水COD降为60-80mg/L,BODo 50-60/L,色度为100-150CU,挥发性酚的质量浓度小于0.0265mg/L。 相似文献
52.
George Ter-Stepanian 《Bulletin of Engineering Geology and the Environment》2002,61(3):197-205
The paper discusses the postulated suspension force, by which it is possible to explain some enigmatic phenomena observed
in different types of mass movements. This force is generated in thick suspensions as a result of friction between sinking
solid particles and static water. The suspension force is related to the seepage force but they have opposite directions.
Both forces form flow networks. Having explained the suspension force, the paper describes how this influences the movement
of material, particularly in debris flows. Enigmatic features and the mechanism of debris flows and lahars are explained by
virtue of the suspension force.
Electronic Publication 相似文献
53.
摩擦强度对薄膜表面形态的作用:原子力显微镜下的观察 总被引:2,自引:2,他引:0
展示了摩擦强度对聚酰亚胺薄膜表面形态的影响,原子力显微图像显示,机械摩擦会使聚酰亚胺薄膜表面上形成微沟槽,这些沟槽的表面具有丰富的表面精细构造。原子显微图像还揭示了机械摩擦可以改变被磨擦聚酰亚胺膜的表面形态。 相似文献
54.
55.
Gibbs energies of formation of CoF2 and MnF2 have been measured in the temperature range from 700 to 1100 K using Al2O3-dispersed CaF2 solid electrolyte and Ni+NiF2 as the reference electrode. The dispersed solid electrolyte has higher conductivity than pure CaF2 thus permitting accurate measurements at lower temperatures. However, to prevent reaction between Al2O3 in the solid electrolyte and NiF2 (or CoF2) at the electrode, the dispersed solid electrolyte was coated with pure CaF2, thus creating a composite structure. The free energies of formation of CoF2 and MnF2 are (± 1700) J mol−1; {fx37-1} The third law analysis gives the enthalpy of formation of solid CoF2 as ΔH° (298·15 K) = −672·69 (± 0·1) kJ mol−1, which compares with a value of −671·5 (± 4) kJ mol−1 given in Janaf tables. For solid MnF2, ΔH°(298·15 K) = − 854·97 (± 0·13) kJ mol−1, which is significantly different from a value of −803·3 kJ mol−1 given in the compilation by Barinet al. 相似文献
56.
The nanomechanical characteristics of polycarbonate (PC) polymer were investigated by atomic force microscope (AFM) and nanoindentation. Scratching, wear properties, hardness and Young's modulus were obtained. The relationships between scribing feed and speed, surface depth and roughness and applied load were also investigated. The results indicated that as the applied load was increased, the furrow depth and the surface roughness increased. When the scribing feed was increased, the depth and roughness decreased. Increasing the furrow speed also decreased the surface roughness. The applied load is more significant than the scribing speed on the material removal rate. In addition, the Young's modulus and hardness of the polycarbonate material were 1.8 and 0.2 GPa, respectively. 相似文献
57.
D. Golberg P.S. Dorozhkin Y. Bando M. Mitome C.C. Tang 《Diamond and Related Materials》2005,14(11-12):1857
Various multi-walled nanotubes in the B–C–N system are thoroughly investigated using a JEOL-3100FEF high-resolution field emission transmission electron microscope operating at 300 kV and equipped with an in-column built Omega filter. Spatially-resolved B, C and N elemental maps of the nanotubes are constructed. It is realized that a wide variety of tubular arrays composed of B, C and N atoms may exist in the system. Sandwich-like BN-rich and C-rich alternating tubular shells, graphitic C layers inside and outside of pure BN shells induced either by surface contamination, or electron beam irradiation, separation of C-rich and BN-rich tubes and/or BN particles within tubular bunches may take place. One should carefully take these effects into account while analyzing nanotube physical properties, e.g., electrical or optical, rather than simply rely on electron energy loss spectra typically collected from B, C and N containing nanostructures as a whole. Striking dependence of an individual nanotube electrical conductivity on tubular shell chemistry is demonstrated using I–V curve recording in an atomic force microscope. 相似文献
58.
P. M. Solozhenkin E. A. Deliyanni V. N. Bakoyannakis A. I. Zouboulis K. A. Matis 《Journal of Mining Science》2003,39(3):287-296
The original method is developed for producing the new inorganic sorption material of akaganeite bgr-FeO(OH). The material in question is characterized relative to arsenic contained in aqua. The possibility is established for removing arsenate ions from water by contemporary physicochemical methods. 相似文献
59.
The formation of a crosshatched morphology during crystallization of an isotactic polypropylene with low crystallinity is studied in detail. Here, a lamella seems to grow through another nearly perpendicular lamella that was crystallized before. The crystallization was observed with in situ scanning force microscopy with a temporal resolution of 3 min per image. After crystallization the volume structure was imaged by nanotomography. A detailed scheme for the nucleation of branches is proposed. 相似文献
60.
针对铁路提速后出现的上承式简支钢板梁桥跨中横向振幅过大的问题,以羊楼司桥(L=32m单跨上承式简支钢板梁桥)为例进行实桥检测和数值模拟,建立车辆、线路、桥梁三者的联合模型,考虑轮轨接触力,应用MSC/DYTRAN大型结构分析程序进行车线桥动力相互作用的仿真分析。研究揭示我国用量最多的C62型货车以70∽80km/h的速度空载通过时,该跨度的钢板梁桥发生横向谐振的机理。此外,用该方法对32m跨长的组合梁结构进行桥梁动力特性及列车走行性分析,表明该结构满足提速货车和高速电动旅客列车走行的要求。研究结果对我国高速铁路桥梁建设和既有桥梁的改造具有积极意义。 相似文献