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81.
Following a 1986 study reporting a predominance of ambivalent attachment among insecure Sapporo infants, the generalizability of attachment theory and methodologies to Japanese samples has been questioned. In this 2nd study of Sapporo mother-child dyads (N=43), the authors examined attachment distributions for both (a) child, based on M. Main and J. Cassidy's (1988) 6th-year reunion, and (b) adult, via the Adult Attachment Interview (AAI). In contrast to the previous Sapporo study, children's 3-way or "organized" distribution did not differ from the global distribution. However, when the disorganized-controlling (D) and cannot classify (CC) categories were applied to the analyses, a high proportion of D/CC children was found. Comparable analyses for Japanese mothers, including the unresolved/disorganized (U) and CC categories, were found to deviate slightly from the global norm. However, turning from global distributions to mothers' AAI classification as related to their child's reunion classification, all matches were surprisingly close to those established worldwide. When, as is customary, mothers' U and CC classifications were combined (U/CC) and compared with the child's D and CC classifications (also customarily combined as D/CC), mothers' U/CC status strongly predicted child D/CC status (r=.60, d=1.50). Additionally, mothers' AAI subclassifications predicted child subclassifications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
M. W. Liang T. E. Hsieh S. Y. Chang T. H. Chuang 《Journal of Electronic Materials》2003,32(9):952-956
The multilayer thin-film systems of Cu/Ti/Si and Au/Cu/Al2O3 were diffusion-soldered at temperatures between 250°C and 400°C by inserting a Sn thin-film interlayer. Experimental results
showed that a double layer of intermetallic compounds (IMCs) η-(Cu0.99Au0.01)6Sn5/δ-(Au0.87Cu0.13)Sn was formed at the interface. Kinetics analyses revealed that the growth of intermetallics was diffusion-controlled. The
activation energies as calculated from Arrhenius plots of the growth rate constants for (Cu0.99Au0.01)6Sn5 and (Au0.87Cu0.13)Sn are 16.9 kJ/mol and 53.7 kJ/mol, respectively. Finally, a satisfactory tensile strength of 132 kg/cm2 could be attained under the bonding condition of 300°C for 20 min. 相似文献
83.
The purpose of the present study is to examine the relation between quality of mother-child interaction in a lab and home setting, and quality of attachment of school-age children. A second objective of the study is to evaluate the associations between quality of mother-child interactions, attachment and maternal psychosocial measures (social support, depression, and parental stress). Security of attachment (Separation-Reunion procedure, Main & Cassidy, 1988) and the quality of mother-child interaction was evaluated for a sample of 38 children (mean age = 6 years). Mothers also completed self-report measures for depression, stress, and social support. Concurrent to the lab assessment, quality of mother-child interaction was also evaluated during a home visit. Results indicated a strong association between interactive patterns in both settings. Moreover, interactive patterns differed in terms of attachment classification with secure children showing the most harmonious patterns and disorganized/controlling children showing the most dysfunctional patterns. Maternal psychosocial measures were not related to child security of attachment, but mothers of insecure children reported marginally more stress related to the child. Maternal psychosocial adjustment was, in part, related to dyadic mother-child interaction in the home and lab setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Aminoalkanethiol surface modifiers were investigated on gold electrodes. It was established, that quinone molecules could be attached to these surface layers in three different forms with well-distinguished redox potentials. Chemical reaction with the amino groups of the modifiers could produce monosubstituted and disubstituted quinones attached covalently to the layers. However, a third form could be detected, as well that seems to be quinone attached non-covalently to the monosubstituted quinone molecules. 相似文献
85.
Suxia Zhang 《Electrochimica acta》2004,49(26):4777-4786
A novel and facile approach to construct multilayered glucose oxidase (GOx) films on the surface of quartz or CaF2 slides as well as gold electrodes for use as biosensing interfaces is described. Diazo-resins (DAR) as polycation and glucose oxidase as polyanion were alternately deposited into a multilayer structure using layer-by-layer self-assembly technique based on electrostatic interaction as driving force. Upon near UV irradiation, the adjacent interfaces of the multilayer reacted to form a crosslinking structure which greatly improved the stability of the enzyme films. These changes was monitored and confirmed by UV-vis and IR spectroscopy. Ellipsometric measurements reveal that the enzymes formed sub-molecule layers, and the thickness of the film shows a linear relationship with the number of assembled layers, demonstrating a spatially well-ordered manner in multilayer structure. The covalently attached enzyme multilayer film has a highly permeable structure, and can be used as biosensing interface. Electrochemical and analytical behavior of the enzyme electrodes was studied by cyclic voltammetry (CV) in the presence or absence of glucose. The sensitivity of the enzyme-modified electrodes was estimated through the analysis of voltammetric signals, which can be fine turned to the desired level by adjusting the number of attached bilayers. 相似文献
86.
微生物矿化技术作为一个新兴研究课题,近些年来得到了广泛关注,然而因其反应机制复杂,很难从时间和空间尺度对矿化反应过程进行定量表示。在微生物诱导碳酸盐沉淀原理的基础上,考虑细菌的吸附和筛滤效应,以及尿素水解动力学和沉淀动力学模型,对微生物矿化反应动力学理论进行了探究,并结合孔隙尺度下的微生物矿化反应试验,采用有限元软件进行多物理场耦合模拟。结果表明,细菌吸附和筛滤行为引起了细菌分布的差异性,而这种差异性进而影响了碳酸钙的沉积分布;溶液汇合初始段碳酸钙生成量横向分布不均匀,纵向分布呈增长趋势;经历40h的反应时间,渗透率可降低80%左右;当钙离子含量丰富时,碳酸钙沉淀速率受限于尿素水解速率;附着细菌量和沉淀速率的叠加效应表现为细菌被沉淀包裹的衰亡速率。本模型验证了微生物矿化沉积反应过程,丰富了微生物矿化反应理论,并有望为现场工程应用的效果预测提供参考。 相似文献
87.
风机叶片对雷电的接闪是风机防雷研究中的关键内容,合理分析接闪时的击距特性意义重大。基于雷击过程的物理机制,将雷击发生时上、下行先导头部间的距离定义为跃变击距,并分析了多上行先导竞争对风机接闪和跃变击距的影响。基于先导起始和发展理论,根据下行先导的等效模型和稳定上行先导的判定方法建立了风机叶片接闪模型,利用该模型得到了随雷电流幅值变化的跃变击距公式,指出侧面距离等参数对跃变击距没有影响,实验和观测结果证明了模型的正确性。最后利用接闪模型提出了考虑稳定上行先导对周围电场畸变作用的对地击距公式,与其他学者计算的结果进行对比指出,现有对地击距公式或不适用于风机背景的防雷计算。 相似文献
88.
采用水热法,分别以丙二酸、正丁醇、乙二胺为表面活性剂,研究3种体系下TiO2纳米晶体的生长过程。XRD结果显示3种体系下主要产物为锐钛矿TiO2;TEM和HRTEM结果表明在不同的生长阶段,纳米晶体的生长结构特点明显不同。分别采用定向生长理论(Orientation attachment,OA)、弗兰克尔收缩理论(Frenkel shrinking,SH)、奥斯特瓦尔德熟化理论(Ostwald ripening,OR)对3种体系下的晶体生长进行理论模拟,结果发现在丙二酸、乙二胺体系下晶体生长分为3个阶段:定向聚集生长、颗粒收缩、奥斯特瓦尔德熟化,且乙二胺体系下颗粒明显增大;但是在正丁醇体系下晶体生长仅显示明显的OR特征,不存在OA生长。理论和实验分析说明不同体系下晶体生长方式不同的主要原因是由于3种表面活性剂以及溶液pH值的不同作用。 相似文献
89.
Bacterial attachment is highly dependent on a surfaces microstructure. For example, some rough surfaces provide grooves suitable for bacterial adhesion. Superhydrophobic surfaces with a Cassie-Baxter wetting mechanism are shown to prevent contact between a bacterium and surface attachment points. The surface used in this study is a highly rough thin film made from a silicone elastomer via an aerosol assisted chemical vapour deposition (AACVD) process. The films had water contact angles averaging 165°, a very low slip angle, and were capable of duplicating the Lotus effect. The ability of bacteria (Escherichia coli and Methicillin-resistant Staphylococcus aureus) to adhere to this surface was tested by submersion in a bacterial suspension. The superhydrophobic elastomer surfaces reduced the attachment of the bacteria tested, relative to the control surfaces of plain glass, and flat elastomeric films. The reduction in bacterial adhesion, without the external action of chemicals, gives the elastomer surface deposited with AACVD possible applications in biomedical and catering industries. This progressive study of bacterial adhesion is carried out on an AACVD prepared surface and presents adhesion results from both smooth and highly roughened elastomeric surfaces. 相似文献
90.
Water structure is the most important parameter that influences the flotation of soluble salts. In this paper bubble attachment time measurements and FTIR analyses were performed to investigate the effect of water structure on the flotation behavior of sylvite (KCl), bischofite (MgCl2·6H2O) and carnallite (KMgCl3·6H2O). The results from bubble attachment time measurements suggest that collector adsorption at the surface of KCl induces flotation with either the cationic collector, ODA, or anionic collector, SDS. In contrast bubble attachment did not occur for bischofite (MgCl2·6H2O) or carnallite (KMgCl3·6H2O). Results show that the surface charge is not a determining factor in the flotation of soluble salts.Further, the interaction between water molecules and the three chloride salts dissolved in aqueous solution were studied by measuring the shift in the hydrogen-bonding of water molecules. The results indicate that KCl is a structure breaker salt, while MgCl2·6H2O and KMgCl3·6H2O are structure maker salts.Viscosities for the brines of these three salts were determined. The results give additional evidence of differences in water structure and are in good agreement with the FTIR and bubble attachment results. The findings provide further evidence that water structure plays an important role in the flotation of soluble salts. 相似文献