桐油改性酚醛树脂的结构及固化过程的研究

通过桐油与苯酚在酸性催化剂存在下反应，然后再在碱性催化剂存在与甲醛反应制得了一种热固性桐油改性酚醛树脂。利用红外光谱，差示扫描量热法分析技术对改性树脂的结构及固化反应过程进行了研究。     

机电排灌工程管理之我见

机电排灌工程是丘陵、滨湖地区的主要灌溉设施，必须建立适应市场经济的管理新机制，确保工程良性运行和巩固发展，满足不断发展的工农业生产需要。     

In—situ Composite Based on Poly （ethylene terephthalate）,Polyamide and Polyethylene with Microfibres Formed through Extrusion and Hot Stretching

In-situ composites based on dispersed poly (ethylene terephthalate) (PET) or polyamide (PA),and continuous Polyethylene (PE) were prepared through a single screw extruder of Haake rheometer system with a rod-die relatively small in diameter.The extrudate was drawn at a drawing ratio of 3.1,and then quickly cooled in cold water.The specimens were obtained by injection molding at processing temperatures less than 190℃，far below the melting temperature of PET (265℃) and PA (230℃),which can maintain the solid state of PET and PA microfiber phase in the composites.Morphological observation with scanning electron microscopy (SEM) indicated that PET and PA can more or less form in-situ microfibers at compositions studied (0-20 wt pct PET or PA),and especially,PET and PA were almost deformed into fibers at the concentration of 15wt pct.Eensile strength and especially.PET and PA were almost deformed into fibers at the concentration of 15wt pct.Tensile strength and modulus of the blends reinforced by PET or PA microfibers showed to be increased from the tensile test results.The most noticeable improvement of the tensile properties occurred at 15wt pct of PET in PET/PE system,corresponding to the highest microfiber content,where the tensile strength reached 32.5 MPa,whereas only 19.5 MPa for the pure PE.     

Electrorheological Fluids Based on Titania Particles Coated with Silica and Their Application in Smart Windows

The electrorheological (ER) fluids are colloidal suspension of highly polarizable particles in a non-conducting solvent.Chains of submicron-sized particles formed along an applied DC electric field by the so-called electrorheological effect.According to the obvious change of transmittance of the ER fluids in a DC electric field when the polarized particles arranged along the field,the model of smart window was proposed by sandwiching the ER fluids based on titania particles coated with silica between a pair of In-Sn oxide (ITO) coated glasses.The solar transmittance change as much as 48.0% was obtained with the wavelength of 500 nm at the maximum on applying and removing the electric field of 500V/mm.     

纳米氧化铝的制备及应用

介绍了高科技产品纳米氧化铝的 3大制备方法 :固相法、气相法、液相法的优缺点 ,以及纳米氧化铝的应用与发展前景     

光学全交叉网络与SW榕树（F＝S＝2）网络拓扑等价的多样性

本文对有关互连网络拓扑等价的分析方法作了简单评述。并采用互连网络拓扑等价的图分析法分析了自由空间光学互连全交叉网络与ＳＷ榕树网络的拓扑等价及其多样性，拓展了全交叉网络在数字光计算、光子交换及多处理机系统的潜在应用。     

Synthesis and aqueous solution behaviors of sodium sulfonate‐terminated dendritic poly(ester‐amine)

Sodium sulfonate‐terminated dendritic poly(ester‐amine) (SPEA) was synthesized by sulfonation of acrylic double bond‐terminated dendritic poly(ester‐amine) (APEA) with sodium hydrogen sulfite (NaHSO₃) in mixture of diglycol and 2‐butanone under normal pressure. The structure of SPEA was characterized by IR, ¹H‐NMR, and elemental analysis. SPEA was water‐soluble. 1.0–40.0% (mass) SPEA aqueous solutions appeared as dilatant fluid. When pH value varied from 1.5 to 12.0, the viscosity of 1–5% (mass) SPEA aqueous solutions changed very small, and the electric conductivity almost kept stable within pH 3.0–10.0. The relationship between the viscosity and the concentration of SPEA water solutions was similar to that of NaCl water solutions. The surface tension of SPEA water solutions was lower than that of polyethylene glycol 2000 water solutions with the same concentration. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Shear-induced crystallization of poly(phenylene sulfide)

The crystalline morphology of poly(phenylene sulfide) (PPS) isothermally crystallized from the melt under shear has been observed by polarized optical microscope (POM) equipped with a CSS450 hot-stage. The shish–kebab-like fibrillar crystal structure is formed at a higher shear rate or for a longer shear time, which is ascribed to the tight aggregation of numerous oriented nuclei in the direction of shear. The crystallization induction time of PPS decreases with the shear time, indicating that the shear accelerates the formation of stable crystal nuclei. Under shear, the increase of spherulite growth rate results from highly oriented chains. The melting behavior of shear-induced crystallized PPS performed by differential scanning calorimetry (DSC) shows multiple melting peaks. The lower melting peak corresponds to melting of imperfect crystal, and the degree of crystal perfection decreases as the shear rate increases. The higher melting peak is related to the orientation of molecular chains. These oriented molecular chains form the orientation nuclei which have higher thermal stability than the kebab-like lamellae that are developed later. A new model based on the above observation has been proposed to explain the mechanism of shish–kebab-like fibrillar crystal formation under shear flow.     

宝钢曲轴用非调质钢的生产与展望

在实验室研究的基础上，开发了屈服强度为520MPa级的曲轴用微合金化非调质钢48MnV。工业生产了6000余吨φ151mm大规格圆钢，其各项性能满足了用户要求。指出了宝钢曲轴用非调质钢开发和努力的方向。     

Al2O3/TiB2/SiCw三元复合材料的力学性能及显微结构

以Al₂O₃为基体,SiC晶须和TiB₂颗粒两种增韧剂,采用热压烧结工艺制备了Al₂O₃/TiB₂/SiC_w三元复合陶瓷材料。研究了热压工艺参数对材料致密度的影响和晶须含量对该复合材料的力学性能和显微结构的影响。结果表明;随晶须含量的增加,该复合材料的热压温度和保温时间需要相应的增加;晶须拔出、裂纹偏转和晶须的桥接为该复合材料的主要增韧机理;随晶须含量的增加,该材料的室温断裂韧性增加;该材料的断裂韧性随温度的升高而呈增大趋势,并且晶须含量越高,材料的高温断裂韧性增幅越大。