SFA废水以PSB方式生物降解工艺路线之抉择

本文着重研究PSB处理SFA废水的优化工艺条件。经SFA废水成分的测定,探索了该废水“边可溶化边PSB降解”的“双边”处理的可能性,改进了日本小林正泰提出的必须“先可溶化后PSB降解”的“先后”处理的传统理论。在研究废水的预处理工艺以及溶解氧与去除率关系等基础上,揭示了处理系统生物化学代谢变化的规律,并进而探讨了后续工序的处理方法及菌体利用的可能性。试验表明,PSB法在有机废水处理中是有应用前途的新工艺。     

MATLAB在输电线故障测距中的仿真应用

计算机仿真是输电线故障测距分析的一种重要手段，而MATLAB中的PSB电气系统模块，为各种电气系统的设计提供了一种便捷的仿真工具。本文论述了PSB在电力系统仿真中应用。并利用PSB对输电线的故障定位进行了算例仿真。     

电致发光材料三芳胺聚合物的能带结构表征

采用循环伏安(CV)法结合紫外-可见(UV-Vis)吸收光谱表征了4种新型电致发光材料三芳胺聚合物TPD(PTPD)的能带结构,并对引入的基团及分子结构对其能带结构的影响进行了探讨。结果表明,从聚合物TPD和小分子TPD的UV-VIS吸收光谱的最大吸收来看,聚合后TPD的能带结构没有太大的改变。从循环伏安图看出,材料的具有较好电化学稳定性。并制成了ITO(氧化铟锡)/PTPD/Alq3(8-羟基喹啉铝)/Mg:Ag异质结电致发光器件,与典型的ITO/TPD/Alq3/Mg:Ag器件进行了比较,研究发现其器件的稳定性有的明显提高。     

SIMULINK在电力电子中的应用

介绍了一种基于Matlab环境下交互仿真软件SIMULINK中的仿真工具——电力系统模块（PSB）,可用于对电力电子系统和电力拖动系统的仿真。通过对PSB主要模块和特点的介绍分析。以及与其他仿真软件特点的比较可以看出,该仿真软件具有很强的开放性、灵活性和交互性,非常适合于电力电子的教学与科研,并结合作者使用中的经验和一个实例,说明PSB的使用方法及分析方法,从中可以看到,该仿真工具在电力电子中具有很好的应用价值。     

基于MATLAB的三相变压器励磁涌流仿真分析

利用MATLAB中的电力系统模块库PSB,建立三相变压器空载模型及短路模型。在此模型基础上对变压器空载合闸和短路故障切除后电压恢复时的励磁涌流进行了仿真,并对此仿真结果进行了分析。仿真结果与理论分析相吻合,表明利用MATLAB/PSB能够有效地实现对变压器励磁涌流的仿真,为变压器保护的算法研究提供基础。     

新加坡PSB集团代表团访问重庆工学院

2006年5月21日至23日，应重庆工学院邀请，新加坡PSB集团总裁邢诒镀、PSB学院院长李明珠一行来我院访问。访问期间，党委书记饶宁华教授、校长刘全利教授等会见了来访的客人，并就我校与PSB学院联合办学的相关问题进行了座谈和交流。来访客人还参观了我校花溪校区并给予了高度评价。     

优势光合细菌处理有机废水的研究

从炼焦废水生物处理系统中分离出了光合细菌(PSB菌)，对高浓度有机废水进行了静态处理，并对炼焦废水进行了动态处理，同时对PSB菌降解有机污染物的机理进行了探讨。结果表明，PSB菌在pH为7和有氧的条件下对大部分的高浓度有机废水有较好的处理效果，其有机物去除效率在90％以上，脱酚效率达96％以上，氰化物去除率高达92％，氨氮去除效果在68％以上。     

循环对称结构在外力作用下的模态特征及位移特性

在循环对称结构受迫响应分析的基础上,从理论上探讨了外载荷不同分布作用下结构的模态特征和位移特性。从而为循环对称结构的多点激振试验、模态分析和载荷识别提供理论依据,并且为模态分类提供一种有效的方法。     

微量元素对废水中光合细菌生长的影响

为了强化光合细菌污水资源化效率,研究微量元素对废水中光合细菌(PSB)生长的影响,利用单因素设计法找出影响菌体产量的2个最显著的因素,以Box-Behnken设计法及响应面分析法确定了主要影响因素的最佳浓度.研究表明:0.66 mmol/L的Fe2+与0.16 mmol/L的Mg2+混合时,PSB菌体产量最高,可达到1 483.5 mg/L,COD去除率最高达到89.1%,成本最低达到0.033元/t.验证结果表明Fe和Mg组合在72 h时菌体产量达到1 380 mg/L,比空白提高了57%.微量元素Fe和Mg组合可促进废水中PSB的生长,可强化光合细菌污水资源化效率.     

燃氢燃气轮机热力学特性分析

本文提出用金属氢化物解决氢能燃气轮机中式的贮存、携带和加压问题。用预冷进气的方案,提高燃气轮机的效率和比功率。文章推导了循环基本热力学方程。对影响循环效率的几个主要因素进行了分析,并用一般回热式燃气轮机循环与本循环进行比较,指出了预冷进气燃氢燃气轮机的优越性能。     

Fatigue cracking characterization of high grade non-oriented electrical steels

The fatigue behavior of 30WGP1600 non-oriented electrical steel, which is generally used in the motors for electrical vehicles, was investigated. The detailed microstructure and dislocation configurations of the fatigue specimens were examined by OM, SEM, and TEM. The test results showed that fatigue cracks were commonly initiated from the surface grain boundaries, crystals plane, and inclusions. The rapid fatigue crack propagation was characterized by transgranular cleavage fracture, while most transient fracture exhibited ductile tearing characteristics. After cyclic deformation of the non-oriented electrical steels, various dislocation structures, such as short and thick lines, veins, persistent slip bands, cells, and labyrinth, were observed.     

基于Voronoi图的晶体塑性有限元多晶几何建模

通常用规则的六边形或四边形等来表示晶粒,不能够反映出晶界的不规则性,本文使用Voronoi方法在大型有限元软件ABAQUS中建立了多晶材料的几何模型,能够表达出晶粒的几何形状与晶界的不规则性;在此基础上提出了一种控制晶粒大小分布及织构的方法,通过调整参数能够建立具有不同晶粒尺寸分布及织构的模型．     

Surface nanostructure formation mechanism of 45 steel induced by supersonic fine particles pombarding

By means of supersonic fine particles bombarding (SFPB),a nanostructured surface layer up to 15 μm was fabricated on a 45 steel plate with ferrite and pearlite phases. To reveal the grain refinement mechanism of SFPB-treated 45 steel,microstructure features of various sections in the treated surface were systematically characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Grain size increases with an increase of depth from the treated surface...     

热连轧403Nb棒材的组织结构与蠕变性能

为了获得403Nb钢更好的加工工艺及优异的高温蠕变性能,借助扫描电镜（SEM）、透射电镜（TEM）、x射线衍射仪（XRD）等分析手段,并通过蠕变性能测试,对热连轧403Nb钢蠕变前后的组织结构及行为进行了研究.结果表明：403Nb钢在热连轧期间发生了动态回复及动态再结晶,其组成相包括：α Fe、（Fe,Cr）23C6及（Fe,Cr,Nb）C,其中,（Fe,Cr）23C6多分布于晶界,（Fe,Cr,Nb）C主要分布于晶内.在实验条件下,热连轧403Nb钢具有极强的温度敏感性和应力敏感性,其蠕变激活能Q=287.5kJ/mol.蠕变期间发生了大量的交滑移,碳化物通过阻碍位错运动以及“钉扎”晶界起到提高蠕变抗力的作用.     

Effect of dislocation configuration on non—equilibrium boron segregation during cooling

Different densities and configurations of crystal defects were obtained in an austenitic Fe-30% Ni alloy and an ultra low carbon bainitic(ULCB) alloy by undergoing different deformations and annealing treatments at high temperatures.Boron segregation on grain boundaries and subgrain boundaries during air-cooling were revealed by means of the particle tracking autoradiography technique.It is found that non-equilibrium segregation is resisted in deformed grains after recovery and polygonization,borondepleted zones seem to be quite clear in recrystallized grains than those in deformed original grains during cooling.Subgrain boundaries and polygonized dislocation cells have a significant effect on non-equilibrium boron segregation during the air-cooling.The results implicates that dislocation configuration is a more important factor affecting boron segregation at grain boundaries rather than the density of defects itself in the grain.     

Microstructure of AISI 304 stainless steel strips produced by a twin-roll caster

By optical inspection of macro-etched metallography and electron back-scattered diffraction (EBSD) mapping,this paper analyzed the microstructure of anstenitic stainless steel strips produced with an equal-diameter twin-roll strip caster.The results indicate that the microstructure of the strips includes two columnar zones with highly compact dendrites and one equiaxed zone.The characteristics,such as grain size and growing direction of columnar grains and equiaxed grains,were investigated.An additional transitional area with many freer grains between the columnar zone and the equiaxed zone was found.As shown in EBSD analysis,small angle boundaries exist both in the columnar zone and the equiaxed zone,although they are especially more in the transitional area.Additionally,some <111> twin boundaries were found in the mierostructure of the strips.     

Microstructure evolution of AZ31 Mg alloy during change channel angular extrusion

Microstructure evolution of AZ31 Mg alloy during change-channel angular extrusion (CCAE) was investigated. The grains of AZ31 Mg alloy were refined significantly from 500 mm to 15 mm after CCAE deformed at 523 K. Dislocations were induced at the initial stage of extrusion and they rearranged themselves to form dislocation boundaries and sub-grain boundaries during deformation. When the specimen through the horizontal change channel with the strain increased, the sub-boundaries evolved to high angle grain boundaries (HAGB). The process of grain refinement can be described as continuous dynamic recovery and recrystallization (CDRR).     

加载路径对铝合金疲劳位错结构的影响

目的研究铝合金材料在相同等效应力幅、不同非比例加载路径下的多轴疲劳寿命以及疲劳失效试件位错结构,从而明确加载路径对位错结构的影响.方法利用透射电镜分析了不同加载路径下疲劳试样的位错结构特征.结果铝合金多轴非比例加载疲劳寿命变化规律为:圆形路径<正方形路径<矩形路径<椭圆形路径,圆形路径下位错以交叉滑移为典型特征,正方形路径下以单方向的滑移线以及拉长的位错环为典型特征,矩形和椭圆形路径下均以三方向的多滑移为典型结构特征.结论加载路径对疲劳寿命有明显影响,不同加载路径下疲劳试样位错结构不同,质点对位错有较强的钉扎作用,位错以线形平行排列塞积在质点前.     

Grain-scale Stress and GND Density Distributions around Slip Traces and Phase Boundaries in a Titanium Alloy

For TA15 titanium alloy, slip is the dominant plastic deformation mechanism because of relatively high Al content. In order to reveal the grain-scale stress field and geometrically necessary dislocation(GND) density distribution around the slip traces and phase boundaries where the slip lines are blocked due to Burgers orientation relationship(OR) missing. We experimentally investigated tensile deformation on TA15 titanium alloy up to 2.0% strain at room temperature. The slip traces were observed and identified using high resolution scanning electron microscopy(SEM) and electron backscatter diffraction(EBSD) measurements. The grain-scale stress fields around the slip traces and phase boundaries were calculated by the cross-correlationbased method. Based on strain gradient theories, the density of GND was calculated and analyzed. The results indicate that the grain-scale stress is significantly concentrated at phase/grain boundaries and slip traces. Although there is an obvious GND accumulation in the vicinity of phase and subgrain boundaries, no GND density accumulation appears near the slip traces.     

Plastic deformation of nanocrystalline nickel

A high-resolution electron microscopy study has uncovered the plastic behavior of accommodating large strains in nanocrystalline (NC) Ni subject to cold rolling at liquid nitrogen temperature. The activation of grain-boundary-mediated-plasticity is evidenced in NC-Ni, including twinning and formation of stacking fault via partial dislocation slips from the grain boundary. The formation and storage of 60° full dislocations are observed inside NC-grains. The grain/twin boundaries act as the barriers of dislocation slips, leading to dislocation pile-up, severe lattice distortion, and formation of sub-grain boundary. The vicinity of grain/twin boundary is where defects preferentially accumulate and likely the favorable place for onset of plastic deformation. The present results indicate the heterogeneous and multiple natures of accommodating plastic strains in NC-grains. Supported by the National Nature Science Foundation of China (Grant Nos. 50571000, 10721202) and the National Basic Research Program of China (“973” Program) (Grant No. 2004CB619305)