资源型城市产业转型模式研究进展

诸多学者分别从资源角度和城市角度对资源枯竭型城市的产业转型模式进行了研究,但从资源角度的研究没有对“城市”这个要素引起足够的重视,而从“城市”角度的研究虽然较多地考虑了“城市”要素对产业转型的作用,但对产业转型模式的研究思路尚需拓宽。针对这些问题,提出了进一步研究的方向。     

银耳多糖与大豆分离蛋白的相互作用及流变性能

研究银耳多糖(Tremella fuciformis polysaccharide,TFP)与大豆分离蛋白(soybean protein isolate,SPI)的相互作用,利用浊度、纳米粒度仪、激光共聚焦扫描显微镜、流变仪、荧光光谱法和傅里叶变换红外光谱法等对TFP与SPI的复合凝聚过程进行表征。结果表明：pH值、SPI与TFP质量比和盐离子浓度对凝聚体的形成影响较大,当SPI∶TFP>1时,与复合物形成相关的关键pH值(pH_c和pH_φ1)向高pH值方向移动。当SPI∶TFP<1时,pH_φ1向低pH值方向移动。随着体系中TFP比例的增大,浊度的最大吸收峰逐渐降低(pH_opt逐渐减小)。当SPI∶TFP=1∶1时,两者在pH 3.0处的相互作用最强,此时体系总体的黏度最大(约为1.30 Pa·s),形成的聚集体最多且粒径最大。NaCl浓度较低(<20 mmol/L)时能促进SPI-TFP凝聚体形成,NaCl浓度较高(≥20 mmol/L)时由于屏蔽作用会抑制凝聚体的形成。当剪切频...     

埋地钢管热缩套补口材料现场应用状况调查与分析

通过对埋地钢管热缩套补口材料的现场应用状况的调查,分析了腐蚀发生的原因,探讨了改进钢管热缩套补口施工工艺和优化补口结构的方法.     

采用差分相位测量方法的MEMS运动表征系统

介绍了一种基于计算机控制的频闪干涉测试系统,用于测量可动微机电系统(MEMS)器件的离面运动,实现了nm级分辨力.系统采用五步相移高精度干涉测量方法,通过选择器件上的固定点作为参考点,实现差分测量模式,有效消除了随机误差的影响,提高了系统测量的重复性,10次测量的重复精度为3.17 nm.通过研究微谐振器的离面运动特性,说明该系统的强大功能.     

塑造特色空间提升空间地位——徐州九里山片区概念规划

徐州市九里山片区概念规划针对九里山片区作为一个边缘化的中心城市的边缘地带、一个产业结构亟待调整的传统矿区、一个生态环境亟待整治的塌陷地,从资源、产业、空间三个角度确定了能提升九里山片区地位、塑造特色空间、促进资源整合、推动产业结构调整的三大战略--城市品牌发展战略、可持续发展战略和"生态九里"发展战略.     

弱酸离子交换纤维的结构表征与性能研究

采用预辐射接枝法,引发聚丙烯(PP)纤维接枝丙烯酸(AA),制备出接枝率为235%～298%,平均交换容量为9.65mmol/g,物理机械性能良好的弱酸离子交换纤维(PP-g-AA).利用分析仪器对PP-g-AA纤维的结构进行表征,并对其机械强度、热稳定性、交换容量、接枝率、化学稳定性等物理与化学性能进行了测试.结果表明,利用预辐射接枝法制备的PP-g-AA纤维具有较高的交换容量、快的吸附速度、较好的机械性能和稳定的化学性能,是一种性能优良的功能材料.     

纳米氟硼酸钾粉末的制备及表征

探讨了高能球磨法制备纳米KBF4粉末的工艺过程及影响因素.通过选择合适的球磨工艺及表面活性剂,以普通KBF4粉末为原料成功制备出粉末的粒度均径为81.2nm、比表面积为28.26m2/g的纳米级KBF4粉末.分别采用BET比表面积测试法、X射线小角度散射法(SAXS)及扫描电镜对纳米KBF4粉末进行了表征.     

Characterization of the interfacial-microstructure evolution and void shrinkage of Ti-22Al-25Nb orthorhombic alloy with different surface roughness during diffusion bonding

Ti-22Al-25Nb alloy specimens with different surface roughness were joined, through diffusion bonding at 975 °C at 12.5 MPa. The interfacial-microstructure evolution during this process was characterized via scanning electron microscopy combined with electron probe microanalysis and electron backscatter diffraction analysis. Further, the interfacial void-shrinkage mechanism and the quality of the bonded joints were determined through atomic force microscopy, which revealed the three-dimensional morphologies of the surfaces, and shear strength testing of the joints. The results revealed that fine equiaxed α₂ grains are precipitated in the bonding interface of specimens with ground surfaces. These interfacial α₂ grains were formed via phase transformation and recrystallization processes, which were triggered by asperity deformation at the contact plane and unavoidable oxygen contamination. Two types of fracture occurred during the shear strength tests, where the bonds generated from (i) polished surfaces failed predominantly along the bond line, and (ii) ground surfaces failed predominantly in the base material away from the bond line. This indicated that the mechanism controlling the void-shrinkage process associated with the contact between two rough surfaces during diffusion bonding varied with the surface roughness: the void-shrinkage process of specimens with (i) polished surfaces is controlled by diffusion, and (ii) ground surfaces was controlled by both diffusion and plastic deformation.     

Influence of microbiological and chemical quality of traditional starter made from cassava on “attiéké” produced from four cassava varieties

Attiéké is a steamed fermented cassava semolina and food now included in many African countries habits. Non-control of production factors is an important constraint causing manufacturing defaults. Moreover, toxic varieties are used in fermented foods.The aim of this study was to characterize and optimize microbiological, physicochemical and biochemical qualities of attiéké Ebrié. The analyses were performed on traditional inoculum and 4 cassava varieties.The lactic fermentation of cassava dough had positive impact on microbiological and chemical qualities of prepared attiéké that showed slight acidity (pH = 4.6), high starch (80–90 g/l00 g) and low cyanide contents (2.79–5.00 mg/kg). Therefore, sweet varieties are suitable for preparing attiéké.     

Conformational study of the structure of 18-thiacrown-6

Conformational analysis was performed for 18-thiacrown-6 (18t6) using the CONFLEX method and the MMFF94s force field. Computations were performed for some of the low energy conformations at the HF, B3LYP, CAM-B3LYP, M06, M06L, M062x, M06HF and MP2 levels. The computations were also performed using the DFT-D3 method along with the TPSS and PBE functionals. The study predicted a new C₂ conformation as the ground state conformation of 18t6. This new C₂ conformation is more stable than the experimentally known solid state conformation by 4.7 kcal/mol at the MP2/6-311G** level. This conformation has all of the SCCS dihedral angles adopt exodentate structure. However, the experimentally known conformation of the solid phase has two of the SCCS dihedral angles violating this exodentate rule. It was concluded that for 18t6 stability a linear dihedral SCCS angle requirement is more important than a gauche CSCC dihedral angle requirement.