预处理对Fe－15Cr－4Al合金475℃脆性的影响和钇的作用

１１００℃预处理的Ｆｅ－１５Ｃｒ－４Ａｌ合金在５００℃时效后迅速脆化，８００℃预处理的合金则无脆化倾向。高温处理的合金有明显的Ｓｎｏｅｋ内耗峰，α相中碳、氮的浓度较高。时效后Ｓｎｏｅｋ峰降低，在主峰的高温侧还分裂出一小峰。这表明４７５℃脆化包括碳、氮析出和α＇相析出两个过程。前者在时效初期有极强的脆化作用，后者在时效数百小时后才显示出微弱的影响。中温预处理的合金无Ｓｎｏｅｋ峰，碳、氮已充分析出，它们不再发生时效析出。含０．２和０．４ｗｔ％Ｙ的合金不出现４７５℃脆性。内耗无Ｓｎｏｅｋ峰，合金中碳化物、氮化物极少。Ｙ－Ｆｅ相俘获杂质原子，消除碳、氮的时效析出，是钇抑制４７５℃脆性的原因。     

Ti-6Al-4V合金的时效组织与硬度研究

本文研究了明Ti-6Al-4V合金在510℃下不同时间时效后组织及硬度变化。结果发现该合金在940℃固溶、510℃时效时，先从亚稳定β相中析出近等轴状的α相；延长时效时间，α相向片状生长，形成α集团，在集团内片状α的取向趋于一致，而集团间的取向不一致，这导致合金的硬度增加；继续增加时效时间，发生马氏体的分解，片状α相向等轴状转变，合金硬度降低。538℃时效时，硬度比510℃时高。采用多弧离子镀在Ti-6Al-4V合金表面形成了一层很薄且致密的(Ti，Al)N层，镀层可提高合金的显微硬度。     

Cu－Zn－Al形状记忆弹簧的热循环特性

本文研究了Ｃｕ－Ｚｎ－Ａｌ形状记忆弹簧在外加应力不同热循环方式下的性能变化规律，试验分别测试了弹簧的低温残余应变和高温残余应变，结果表明：在外加应力的热循环过程中，影响双程记忆性能的主要因素是高温残余应变，不完全相变热循环时记忆性能衰减缓慢。     

Cu－Zn－Al合金双程形状记忆性能的衰减特性

本文研究了在冷热循环过程中Ｃｕ－Ｚｎ－Ａｌ合金双程记忆性能的衰减规律。实验分别考察了高温和低温残余应变的变化规律，结果表明：双程记忆性能的衰减可分为两个阶段，在第一阶段性能的衰减主要与热弹性马氏体的再取向有关，而在第二阶段性能的衰减与位错的增殖有关。     

稀土对Fe－C－Al－Si铸铁组织和性能的影响

本文研究了稀土对Ｆｅ－Ｃ－Ａｌ－Ｓｉ铸铁的石墨形态，基体组织，力学性能及激冷倾向的影响。随１~＃稀土量增加，石墨由片状向蠕虫状转变较快，但由蠕虫状向球状转变很慢，故具有较大的蠕化范围。铸铁的强度在０．３～１．２％１~＃稀土范围内随稀土的增加而增加，但在１．２～２．０％范围内稍有下降。稀土具有较强的促进激冷倾向的能力，而铝具有抑制或消除激冷倾向的作用。孕育能显著降低激冷倾向，且其效果比普通铸铁更明显。并对有关机理进行了讨论。     

快速凝固粉末冶金Al－Li合金性能研究

采用快速凝固粉末冶金法（ＲＳ／ＰＭ）制备Ａｌ－Ｌｉ－Ｍｇ－Ｃｕ－Ｚｒ合金（合金经固溶时效处理）．测试了合金的拉伸性能，并借助于ＳＥＭ、ＴＥＭ探明了该合金的时效强化机理．     

少量Mn对Cu－15Ni－8Sn合金时效硬化的影响

本文对真空熔铸含Ｍｎ量为０．４６ｗｔ％的Ｃｕ－１５Ｎｉ－８Ｓｎ合金的时效硬化、形变时效使化过程及其组织变化作了研究。实验证明：（１）０．４６ｗｔ％Ｍｎ固溶于Ｃｕ－１５Ｎｉ－８Ｓｎ合金中，（２）含少量Ｍｎ的合金的时效硬化、形变时效硬化及组织变化的基本特征与不含Ｍｎ的Ｇｕ－１５Ｎｉ－８Ｓｎ合金相类似，但少量Ｍｎ延缓合金的时效、形变时效过程，增加硬化效果。     

Al—Li合金断裂韧性的研究

研究了时效工艺对一种高强高模Ａｌ－Ｌｉ合金断裂韧性的影响。研究结果表明，时效前的预时效或预变形可促进Ｔ１相析出，从而改善合金的断裂韧性，但在过时效状态，预时效或预变形的有利影响减弱，为获得高的断裂韧性，时效时应避免粗大晶界平衡相的晶界无析出带变宽。     

添加Mn对Cu－9Ni－6Sn合金组织与性能的影响

作者对含０．４６—１．０６ｗｔ％Ｍｎ的Ｃｕ－９Ｎｉ－６Ｓｎ合金的铸造组织、时效和形变时效特征及组织交化、时效合金的耐蚀性变化作了研完。实验证明，合金的铸锭组织、时效硬化、形变时效和组织变化等基本特征与不含Ｍｎ的合金相类似。添加０．４６ｗｔ％Ｍｎ延缓了合金时效和形变时效近程，添加０．７４—１．０６ｗｔ％Ｍｎ加速了合金时效和形变时效近程，但都升高了最佳时效温度，增加了硬化效果和在酸中的耐蚀性。     

Nd－Fe－B永磁体防腐蚀技术进展

介绍了Ｎｄ－Ｆｅ－Ｂ磁体的防腐技术最新进展。合金化法通过增强磁体自身耐蚀性，虽不能完全避免腐蚀的发生，但可简化表面处理；还介绍了各种防护涂层及其特点     

Evidence for preserved emotional memory in normal older persons.

Emotion has been shown to have a modulatory effect on declarative memory. Normal aging is associated with a decline in declarative memory, but whether aging might affect the influence of emotion on memory has not been established. To investigate this, we administered a task that provides a detailed assessment of emotional memory to 80 neurologically normal adults ranging in age from 35 to 85 years. Across ages, memory performance was found to be modulated by the emotional significance of stimuli in a comparable manner (improved memory for gist, compromised memory for visual detail), despite an overall decline in memory performance with increasing age. The results raise the interesting possibility that aging has a differential effect on hippocampal versus amygdala function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Composition dependence of aging kinetics in some Cu-Zn-Al shape memory alloys

Isothermal and nonisothermal aging behaviors of five Cu/(13 to 28)Zn/(3 to 9)A1 (weight percent) shape memory alloys have been investigated. The electrical resistivity during isothermal aging from 180 °C to 340 °C increases with aging time at each aging temperature. The time to reach a constant fraction transformed during the isothermal aging increases with increasing Al content or decreasing Zn content in the Cu-Zn-Al alloys, except alloy D (Cu-18.2Zn-7.2Al). This alloy exhibits a double aging behavior by the earlier formation of the α₁ bainite and the subsequent formation of the cubic γ₂ phase from the β₁ matrix phase. The apparent activation energy of alloy D varies with the fraction transformed by the double aging behavior. However, other alloys A, B, C, and E exhibit isokinetic behavior. The apparent activation energies estimated in the nonisothermal aging from 100 °C to 500 °C are found to be about equal to those obtained in the isothermal aging.     

Repetition Priming and Recognition Memory in Younger and Older Persons: Temporal Stability and Performance.

The dissociation between intact priming and reduced explicit memory in aging has been called into question on the basis of limited information that suggests that priming measures are less reliable than explicit memory measures. No aging study to date, however, has offered a comprehensive examination of the reliability of these measures. Age-related performance and test-retest stability coefficients for multiple priming and explicit memory tasks were compared. Age effects were found on some tasks but not others, and stability was not related to task performance. Stability was similar for implicit versus explicit task instructions, younger versus older persons, and studied versus unstudied items. Results indicate that dissociations between priming and explicit memory performances cannot be accounted for by differential reliability of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transformation squence in a Cu-Al-Ni shape memory alloy at elevated temperatures

Precipitation sequences in a Cu-14 pct Al-4 pct Ni (wt pct) shape memory alloy were studied by means of transmission electron diffraction and microscopy as well as X-ray microanalysis techniques. On aging thin foil specimens up to 550 °C in the electron microscope, an as-quenched sample having a mixture of 2H-type and D0₃-type metastable structures transformed to the stable simple cubic γ₂ phase at or above 450 °C. The remaining matrix either showed precipitates of the fcc α-phase on prolonged annealing at 500 to 550 °C for a longer period, or transformed to martensite on cooling below theM _s temperature (~150 °C).     

Repetition priming in normal aging and Alzheimer's disease: A review of findings and theories.

On repetition priming tasks, memory is measured indirectly as a change in performance due to recent experience. It is often functionally and neurally dissociated from performance on explicit memory tasks, which directly measure conscious recall or recognition of recent events. Repetition priming has therefore been extensively studied in normal aging and Alzheimer's disease, which feature mild to severe changes in explicit memory. Initial studies indicated that repetition priming was immune to the effects of aging and greatly reduced in Alzheimer's disease (AD). As more studies have been performed, however, these initial conclusions appear less clear than before and, in the case of AD, actually misleading. The purpose of this article is to provide a comprehensive review of this rapidly expanding literature, articulate the issues that are critical to interpreting the empirical results, and discuss what new conclusions are suggested by the overall pattern of findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of normal aging and Alzheimer's disease on emotional memory.

Recall is typically better for emotional than for neutral stimuli. This enhancement is believed to rely on limbic regions. Memory is also better for neutral stimuli embedded in an emotional context. The neural substrate supporting this effect has not been thoroughly investigated but may include frontal lobe, as well as limbic circuits. Alzheimer's disease (AD) results in atrophy of limbic structures, whereas normal aging relatively spares limbic regions but affects prefrontal areas. The authors hypothesized that AD would reduce all enhancement effects, whereas aging would disproportionately affect enhancement based on emotional context. The results confirmed the authors' hypotheses: Young and older adults, but not AD patients, showed better memory for emotional versus neutral pictures and words. Older adults and AD patients showed no benefit from emotional context, whereas young adults remembered more items embedded in an emotional versus neutral context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory and aging: Selected research directions and application issues.

Everyday memory failures and long-term memory changes are among the most empirically established, socially expected, personally disconcerting, and widely misinterpreted aspects of human aging. A large, sophisticated, and still growing theoretical research base on memory aging has accumulated over the last several decades. Following a brief summary of a broad swath of selected basic memory aging phenomena, we identify a small subset of relatively recent but well-researched topics that may hold promise for optimizing memory adaptation in late life. Linking research with potential application, we sketch key objectives for three potential directions of intervention in memory and aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory and Aging in Context.

Much research has indicated that aging is accompanied by decrements in memory performance across a wide variety of tasks and situations. A dominant perspective is that these age differences reflect normative changes in the integrity and efficiency of the information-processing system. Contextual perspectives of development, however, argue for consideration of a broader constellation of factors as determinants of both intraindividual change and interindividual variation in memory functioning. The validity of the contextual perspective in characterizing the relationship between aging and memory is examined through a review of studies exploring a variety of alternative mechanisms associated with age differences in performance. It is concluded that a more multidimensional approach to the study of aging and memory is warranted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

倒双级时效对镍基高温合金组织及高温拉伸性能的影响

 研究了固溶+两段时效热处理工艺对镍基高温合金组织及性能的影响。结果表明：镍基高温合金中的γ′相粒子半径大于40 nm时，位错与γ′相的交互作用由切割机制转变为绕过机制，合金强度明显降低；γ′相的长大规律符合Oswald熟化过程规律；合金在第二段时效过程中，晶界碳化物转变成颗粒状，使其塑性显著提高。