固溶温度对Custom 465钢组织与性能的影响

在510 ℃时效条件下,研究了固溶温度在700～1 050 ℃范围内变化对Custom 465钢晶粒度、奥氏体和力学性能的影响.采用扫描电镜对不同固溶温度下冲击试样的断口进行了分析.结果表明,Custom 465钢的最佳固溶温度在900～950 ℃温度范围内;时效态钢中奥氏体主要为逆转变奥氏体.     

Cation Effects on Chromium Removal in Permeable Reactive Walls

Permeable reactive walls have proven to be successful in laboratory and pilot-scale field applications. However, the long-term efficacy of reactive permeable walls has not been established due to the novelty of the technology. Also, the impact of common groundwater ions such as calcium and magnesium (i.e., hardness) on permeable reactive walls is unknown. In theory, the ions may react competitively with chromium in solution and/or other materials on the surface of the zero-valent iron. The ions may also form precipitates that could clog the reactive zone over time, resulting in decreased contaminant removal and a shorter wall lifetime. The purpose of this research was to determine the effects of common groundwater ions on permeable reactive walls. A range of calcium and magnesium concentrations was tested in laboratory columns to determine the effect of these ions on removal of a constant chromium concentration (100 mg/L). Results from the laboratory tests indicated that calcium and magnesium had a significant impact on chromium removal. The most dramatic effects were witnessed at hardness levels up to 140 mg/L as CaCO3 where zero-valent iron capacity was reduced by 45%.     

机械活化黄铁矿在有机电解质中的电化学行为

通过机械活化的方法制备了黄铁矿粉末,以黄铁矿粉末微电极为工作电极,无水乙醇为电解液,加入适量阳离子表面活性剂(十六烷基氯化吡啶)作为离子导体,采用循环伏安法比较研究了机械活化黄铁矿粉末与未机械活化黄铁矿粉末在无水乙醇中的电化学行为。根据Nernst方程,对黄铁矿电极反应的可逆性进行了讨论;通过数值分析法解Fick第二定律,得出循环伏安曲线峰电流、峰电势、半峰电势等参数的关系,对黄铁矿电极在有机电解液中的液相传质过程进行了论证。     

合金成分与组织结构对铝合金阳极氧化的影响

本文叙述合金化元素、杂质元素及显微结构对铝合金阳极氧化的影响，介绍熔铸、热处理、加工成型及化学预处理等工艺参数对阳极氧化的作用。     

Static Behavior of a Historic Roof Structure

Historic roof structures of large monumental buildings are often complex with static behavior that is difficult to grasp. Yet, understanding their static behavior is necessary to adequately preserve and maintain them. The aim of this paper is twofold. The more general aim is to develop use of the finite element method in combination with visualization and to demonstrate its potential both for providing an understanding of historic structures and their static behavior and for supporting a dialogue regarding these matters. The more specific aim is to examine the static behavior of one particular roof structure and the damages to it that occurred. The roof structure selected was that of the medieval Swedish castle of Glimmingehus. A detailed computational model of the roof truss was developed, in terms of which a set of possible causes of the damages observed was simulated. Reliable causes were found and three-dimensional visualizations were carried out to demonstrate their respective influence on the overall structural behavior. As expected, use of visualization in the analysis was found to be very helpful for interpreting the relationship between the computational model and the computed results.     

Nd-Fe-B合金的组织与组成对其腐蚀行为的影响

研究了Nd-Fe-B合金的组织与组成对其腐蚀行为的影响。对Nd-Fe-B合金各主要组成相在纯水和NaCl溶液中电位进行了测定,结果表明E_(富Nd相)(基体相)(富B相)。Nd-Fe-B合金的腐蚀特征是晶界处的富钕相优先腐蚀,然后向晶粒内Nd₂Fe₁₄B基体相扩展。环境腐蚀试验结果表明,Nd-Fe-B合金中加入Dy后,耐蚀性提高;加入Al后,则耐蚀性有所下降。     

冷轧变形对Custom 465钢组织和性能的影响

 研究了冷轧变形对Ti强化马氏体时效不锈钢Custom 465时效析出、逆转变奥氏体相变和力学性能的影响。结果表明：①在510 ℃时效过程中,杆状Ni3Ti金属间化合物持续析出、长大,致使快速发生硬化;②510 ℃时效过程中,发生逆转变奥氏体相变,冷轧变形使逆转变奥氏体相变滞后;③析出Ni3Ti金属间化合物的同时,马氏体基体发生部分回复。     

Effect of Nonlinear Soil Behavior on Inelastic Seismic Response of a Structure

The characteristics of the earthquake motions at the base of a structure are affected by the properties of the underlying soil through the soil amplification and soil–structure interaction phenomena. In this paper the effect of nonlinear soil behavior on the elastic and inelastic response spectra of the motions that would be recorded at the free surface of a soft soil deposit or at the base of each structure is investigated. The analyses are conducted for a soil layer by itself and for a complete soil structure system using a finite element discretization of the soil in cylindrical coordinates and an approximate linear iterative procedure to simulate nonlinear behavior. Studies are conducted for structures, with a constant base and variable height modeled as equivalent linear or nonlinear single degree of freedom systems and an input motion at the base of the soil deposit representative of rock outcrop motions. Both mat and pile foundations are considered. The results illustrate clearly the importance of the nonlinear soil behavior.     

添加剂对Al-In-Ga-Pb合金阳极行为的影响

为改善铝阳极的性能,选用工业纯铝(99.8%),熔炼了Al-0.1 In-0.1 Ga-3Ph合金.在4 mol·L-1 KOH溶液中添加znO,KMnO4,Na2SnO3·4H2O,C4H4O6KNa4H2O,研究添加剂对合金阳极行为的影响.结果表明:溶液中添加znO后合金的析氢腐蚀得到明显的抑制,同时降低了合金的极化;KMnO4的加入可大幅提高合金的开路电位,但对抑制合金析氢腐蚀作用不明显;Na2SnO3·4H2O可提高合金的开路电位,降低极化.复合添加剂(11 mmol·L-1ZnO+0.61 mmol·L-1KMnO4)使合金开路电位负移,并有效抑制其析氢腐蚀,提高了阳极活性,综合性能较佳.     

Saturation and Preloading Effects on the Cyclic Behavior of Sand

In order to study pore water pressure response and liquefaction characteristics of sand, which has previously experienced liquefaction, two series of cyclic triaxial tests were run on medium dense sand specimens. In the first test series the influence of the soil saturation under undrained cyclic loading has been studied. It summarizes results of cyclic triaxial tests performed on Hostun-RF sand at various values of the Skempton’s pore-pressure coefficient. Analysis of experimental results gives valuable insights on the effect of soil saturation on sand response to undrained cyclic paths. In the second series of tests, the preloading influence on the resistance to the sands liquefaction has been realized on samples at various histories of loading. It was found that a large preloading induces a reduction of the resistance of sands to liquefaction.     

含硫有机添加剂对电解铜箔组织性能的影响

采用自制镀液循环电解铜箔实验装置研究了在含胶原蛋白的电解液中加入0～6 mg/L聚二硫二丙烷磺酸钠(SPS)对电解铜箔组织性能的影响.随着SPS质量浓度增加,铜箔光泽增加,粗糙度和抗拉强度降低.利用扫描电镜(SEM)、X射线衍射仪(XRD)、电子背散射衍射(EBSD)分别对电解铜箔微观形貌和组织结构进行分析,发现SPS使铜箔表面由粗糙变得平整,铜箔的晶面择优取向由(220)变为(200).     

Peptide Effects on Social Behavior: Effects of Vasotocin and Isotocin on Social Approach Behavior in Male Goldfish (Carassius auratus).

The authors measured the effects of centrally infused peptides on social approach behaviors in goldfish (Carassius auratus), a social teleost. Vasotocin (VT) inhibited approach responses toward the visual stimuli of conspecifics in the absence of aggressive or sexual olfactory contextual cues in males, and a V1 receptor antagonist stimulated such responses, at least in males that were not highly social in baseline conditions, as did isotocin (IT). In the absence of social stimuli, VT did not affect activity, therefore indicating that the inhibition was not the result of nonspecific effects on arousal or motor functioning. These experiments indicate that VT and IT induce opposite effects on social approach responses in male goldfish and that endogenous VT, at least, is associated with levels of sociality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

成分对高锰合金钢组织和变形特性的影响

27Mn-3Si-3Al和15Mn-2Si-3Al试验合金钢由真空感应炉冶炼成16.5 kg铸锭,1200℃加热,锻成中25 mm棒材。27Mn-3Si-3Al合金钢在应变前后保持单相奥氏体组织,其应力-应变曲线平滑,没有屈服平台和明显的加工硬化峰,该钢经1000℃2h固溶处理后,材料的抗拉强度为692 MPa,伸长率为59%。当钢中Mn含量降至15%,有较多马氏体(Martensite,α′-M)相出现。而且在应变时又使15Mn-2Si-3Al钢中大量奥氏体转变为α′-M相,造成应力-应变曲线产生明显的加工硬化峰,致使该钢的伸长率降低至35%。     

Structure and Catalytic Behavior of CuO-ZrO-CeO2 Mixed Oxides

The effect of doping CuO on the structure and properties of zirconia-ceria mixed oxide was studied. The results show that addition of CuO decreases the reduction temperature of ceria, and stabilizes the cubic structure of mixed oxides, and enhances catalytic activity of CuO-ZrO-CeO2 mixed oxides for CO oxidation. Increasing ceria content in the mixed oxides can enhance the catalytic activity, but some impurities such as sulfate make catalytic activity falling. There is little effect of calcination temperature on catalytic activities, implying that these catalysts are effective with good thermal stability.     

冷变形对Inconel 690合金力学行为与组织的影响

 本文研究了Inconel 690合金在冷轧变形过程中的组织演变和形变强化规律。结果表明,在15%和20%之间存在一个临界应变εL,小于临界变形量时,加工硬化能力随着变形量的增加递减,真应力-真应变曲线可用Ludwigson模型描述,位错运动主要是单系滑移,加工硬化主要来自位错的长程应力场。临界应变到40%变形量之间,加工硬化能力随着变形量的增加又增强,真应力-真应变曲线也可用Hollomon方程描述,位错运动出现了多滑移和交滑移,加工硬化主要是位错滑移和林位错交割的短程交互作用。     

新型除钴有机试剂对锌电解影响的研究

开展了新型除钴有机试剂净化后的新液与使用锌粉、锑盐、硫酸铜净化后的新液进行锌电解对比研究。结果表明,使用新型除钴有机试剂净化后的新液进行锌电解,在电流密度320A/m~2、槽电压3.15~3.3V、槽温28~31℃、时间32h、明胶溶液每2小时10mL、新型有机除Co试剂用量8.5mg/L的条件下,电解过程中锌片外观质量较好,槽面无返溶烧板现象,电流效率86.09%~89.22%,电流效率高出8.35个百分点;随着电解周期的延长,有机物不断富集,电解阴极出现返溶、烧板迹象,但随着活性炭的加入,返溶、烧板现象停止,阴极锌片表面平整光滑。     

Effects of Cross Anisotropy on Three-Dimensional Behavior of Sand. II: Volume Change Behavior and Failure

The volume change behavior of cross-anisotropic sand is studied using results of a series of cubical triaxial tests. The relationships between the volumetric response, failure, and shear localization are addressed. Rates of dilation under various three-dimensional stress conditions are evaluated in conjunction with the peak shear resistance and initiation of shear banding in specimens of dense Santa Monica beach sand. The location of the line in principal stress space along which the tendency to deform changes from compressive to dilative (the characteristic line) is determined using two different methods. The uniqueness of this characteristic line for cross-anisotropic materials is analyzed.     

Effects of Placement Method on Geotechnical Behavior of Hydraulic Fill Sands

Results of an investigation of the geotechnical behavior of a hydraulic sand placed at a land reclamation site in Hong Kong are presented and interpreted. The study was conducted to aid in developing guidelines for quality control of hydraulic landfill placement. The work described consisted of: (1) field investigations; (2) static and cyclic triaxial testing; and (3) calibration chamber tests to study the cone penetration test versus Dr relationships for marine sands obtained from the reclamation sites. The results of this study clearly indicate that the placement technique is the single most important factor controlling the geotechnical behavior of a given type of sand when placed as a hydraulic fill. The weakest zone is generally located just beneath the water level where fill deposition is placed by pipeline discharge.