组合T形截面钢管混凝土柱偏心受压试验研究

在分析各种异形钢管混凝土柱工程应用的基础上,提出组合T形截面钢管混凝土柱。考虑长细比、偏心距等参数的影响,设计制作18个组合T形钢管混凝土柱试件。通过偏心受压试验,对长细比16.0<λ≤28.8的组合T形钢管混凝土柱压弯性能进行研究,考察试件的破坏形态,实测试件的荷载-应变曲线和荷载-柱中挠度曲线,分析各参数对试件偏心受压力学性能的影响。通过试验数据回归分析,参考国内外相关规范,提出组合T形截面钢管混凝土柱偏心受压承载力计算公式。试验结果表明：偏心受压柱均为弯曲失稳破坏,长细比越大,弯曲破坏特征越明显;偏心距越大,试件极限承载力越低。研究表明,组合T形钢管混凝土柱的两个组成部分能很好地协同工作,力学性能较好;所提出的承载力计算公式可供工程设计参考。图10表3参8     

面向规划事权的济南城乡统筹规划体系

在我国多级政府管理体制下,一级规划主管部门对应一级规划事权。城乡统筹规划如何面向规划事权是充分发挥规划职能、构建和谐社会不可回避的问题。济南市立足实际,面向管理需求,对应规划事权,划定市区为规划区,构建由宏观层面的城市总体规划、市区镇村体系规划,中观层面的中心城控制性规划、重点地区次区域规划,微观层面的修建性详细规划、新农村建设规划组成的城乡统筹规划体系,尤其是加强了承上启下的市区镇村体系规划、重点区域的南部山区保护与发展规划、覆盖乡村全域的新农村建设规划,实现市区暨规划区城乡规划的多层次统筹。     

Novel insights into sludge dewaterability by fluorescence excitation-emission matrix combined with parallel factor analysis

Sludge dewatering is of major interest in sludge volume reduction and handling properties improvement. Here we report an approach of fluorescence excitation-emission matrix (EEM) combined with parallel factor (PARAFAC) analysis to elucidate the factors that influence sludge dewaterability. Sludge flocs from 11 full-scale wastewater treatment plants were collected to stratify into different extracellular polymeric substances (EPS) fractions and then to characterize their fluorescence EEMs. Both the normalized capillary suction time (CST) and specific resistance to filtration (SRF) were applied to determine sludge dewaterability. The results showed that fluorescence EEMs of tightly bound fractions were not affected by the wastewater sources. In contrast, fluorescence EEMs of loosely bound fractions were affected by the wastewater sources. All the fluorescence EEMs could be successfully decomposed into a six-component model by PARAFAC analysis. Both normalized CST and SRF were significantly correlated with component 1 [excitation/emission (Ex/Em) = (220, 275)/350] in the supernatant fraction, with components 5 [Ex/Em = (230, 280)/430] and 6 [Ex/Em = (250, 360)/460] in the slime and LB-EPS fraction. These results reveal that except for proteins-like substances (component 1), sludge dewaterability is also affected by humic acid-like and fulvic acid-like substances (components 5 and 6) in the slime and LB-EPS fractions. Furthermore, this paper presents a promising and facile approach (i.e., EEM-PARAFAC) for investigating sludge dewaterability.     

谐波励磁同步发电机负载谐波磁场分析

用有限元的计算方法对谐波励磁同步发电机进行电磁场计算及负载谐波磁场分析，得出样机的矢量磁位At、磁力线分布图和磁密分布图。根据处理计算结果，得到谐波励磁同步发电机的旋转磁场波形、谐波绕组电压波形和谐波绕组负载特性曲线。通过谐波励磁同步发电机上的实验结果与计算结果的比较说明了方法的正确性，为谐波励磁同步发电机的设计提供了理论依据。     

氧化锌基光催化剂的研究进展

概述了氧化锌(ZnO)基材料的制备方法以及作为光催化剂在国内外的研究进展.重点介绍了用氧化锌基材料作为光催化剂所面临的难题以及研究解决的方法.展望了氧化锌基光催化剂的发展方向和应用前景.     

短玻璃纤维/硅橡胶发泡复合材料的制备及表征

表面改性的短玻璃纤维和硅橡胶共混发泡制备出短玻璃纤维/硅橡胶发泡复合材料,对其力学性能、热性能和结构进行测试。结果表明:当加入长为6mm的短纤维3g(7.5份)时,复合材料的拉伸强度增加155%,达到0.78MPa。沿着纤维取向上的拉伸强度相对于垂直纤维横向增加130%,断后伸长率增加790%;热稳定性提高;结构测试表明复合材料的泡孔孔径平均为0.3mm,呈闭孔且分布稀少,泡孔绕纤维生成;扫描电镜(SEM)显示处理后的纤维与硅橡胶界面处相容性提高。     

He ion irradiation damage in Fe/W nanolayer films

We report on the evolution of microstructure and mechanical properties of Fe/W multilayers subjected to helium ion irradiations. Sputtered Fe/W multilayers with individual layer thickness, varying from 1 to 200 nm, were subjected to He⁺ ion irradiation with a peak displacement per atom value of 6 at ambient temperatures. Helium bubbles, 1-2 nm in diameter, were observed in Fe and W, and more so along layer interfaces. The magnitude of hardness variation after radiation depends on the individual layer thickness. Radiation hardening is observed in specimens with individual layer thickness of ?5 nm. At smaller layer thickness, the hardness barely changes. Analysis indicates that radiation hardening may originate mainly from dislocation loops and partially from He bubbles.     

Ion irradiation induced nanocrystal formation in amorphous Zr55Cu30Al10Ni5 alloy

Ion irradiation can be used to induce partial crystallization in metallic glasses to improve their surface properties. We investigated the microstructural changes in ribbon Zr₅₅Cu₃₀Al₁₀Ni₅ metallic glass after 1 MeV Cu-ion irradiation at room temperature, to a fluence of 1.0 × 10¹⁶ cm⁻². In contrast to a recent report by others that there was no irradiation induced crystallization in the same alloy [S. Nagata, S. Higashi, B. Tsuchiya, K. Toh, T. Shikama, K. Takahiro, K. Ozaki, K. Kawatusra, S. Yamamoto, A. Inouye, Nucl. Instr. and Meth. B 257 (2007) 420], we have observed nanocrystals in the as-irradiated samples. Two groups of nanocrystals, one with diameters of 5–10 nm and another with diameters of 50–100 nm are observed by using high resolution transmission electron microscopy. Experimentally measured planar spacings (d-values) agree with the expectations for Cu₁₀Zr₇, NiZr₂ and CuZr₂ phases. We further discussed the possibility to form a substitutional intermetallic (Ni_xCu_1−x)Zr₂ phase.     

Effects of proton irradiation on electronic structure of NdFeB permanent magnets

Effects of proton irradiation on electronic structure and atomic local structure of N35EH-type NdFeB permanent magnet were investigated by soft X-ray absorption spectrometry and Mössbauer spectrometry. The local coordination environment of Fe atoms changes after proton irradiation, and the average hyperfine field H_in of the magnets decreases from 288.4 to 286.9 kOe. The effects of irradiation on Fe atoms local environment at different lattice sites are different. The near edge structure of Fe L₃ edge is changed, indicating the density of unoccupied state of Fe 3d electrons increases after proton irradiation.     

Development of elastomeric lab-on-a-chip devices through Proton Beam Writing (PBW) based fabrication strategies

In recent years, one of the most exciting developments in fluidic device applications is the rapid evolution of miniaturized micro- and nanofluidic systems, the so called “lab-on-a-chip” devices. These devices integrate laboratory functions into a single chip, and are capable of various biochemical analysis and synthesis, such as sample injection and preparation, single cell/molecule observation, bioparticle sequencing and sorting etc. The evolvement of lab-on-a-chip concept implies the use of novel fabrication techniques for the construction of versatile analytical components in a fast and reproducible manner. Endowed with unique three-dimensional fabrication abilities, Proton Beam Writing (PBW) [1], which is capable of producing nanometer scaled fluidic structures with smooth and straight side wall features, has a great potential to develop all sorts of polymer fluidic devices.In this paper, we describe the batch fabrication of Poly-dimethysiloxane (PDMS) elastomeric lab-on-a-chip devices utilizing PBW technique. A series of fabrication processes, involving PBW, nickel electroplating, soft lithography, polymer dynamic coating and hydrophilic treating, were modified and adopted in our work. Subsequent characterization of individual categories of channel devices was carried out for specific fluidic studies. Respective experimental procedures are presented and results are explained. The channel devices demonstrated good fluidic performance and functionality, suggesting their further application in more complex biological investigations, and the versatility of PBW in lab-on-a-chip development.