Study of the Carbon Steel/Alkyd Coating Interface with a Scanning Vibrating Capacitor Technique

Degradation of the carbon steel/alkyd coating interface is studied with a scanning vibrating capacitor technique. This method is shown to provide information on the state of the metal under the coating, that is, the nature of the metal/polymer electrical double layer, as well as the diffusion rates for water, oxygen, and ionic forms of electrolyte to the steel/alkyd interface. Processes of the hydrolysis of adhesion bonds, metal corrosion, and the polymer's cathodic delamination are investigated. The processes that limit corrosion of the metal under the coating are discussed. It was found that the metal activation and corrosion are determined, for the steel/alkyd system under study, by the oxygen diffusion flux through the polymer and by the formation of differential aeration couples under the coating.     

Intergroup emotions: Explaining offensive action tendencies in an intergroup context.

Three studies tested the idea that when social identity is salient, group-based appraisals elicit specific emotions and action tendencies toward out-groups. Participants' group memberships were made salient and the collective support apparently enjoyed by the in-group was measured or manipulated. The authors then measured anger and fear (Studies 1 and 2) and anger and contempt (Study 3), as well as the desire to move against or away from the out-group. Intergroup anger was distinct from intergroup fear, and the inclination to act against the out-group was distinct from the tendency to move away from it. Participants who perceived the in-group as strong were more likely to experience anger toward the out-group and to desire to take action against it. The effects of perceived in-group strength on offensive action tendencies were mediated by anger. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Effect of Heat‐Moisture Treatment on Structural and Thermal Properties of Rice Starches Differing in Amylose Content

Starches from glutinous rice (1.4% amylose), Jasmine rice (15.0% amylose) and Chiang rice (20.2% amylose) were exposed to heat‐moisture treatment (HMT) at 100 °C for 16 h and at different moisture levels (18, 21, 24 and 27%). The effect of heat‐moisture treatment on structural and thermal properties of these three rice starches was investigated. The HMT did not change the size, shape and surface characteristics of rice starch granules. The A‐type crystalline pattern of rice starches remained unchanged after HMT. The relative crystallinity (RC) and the ratio of short‐range molecular order to amorphous (RSA) of heat‐moisture treated glutinous and Jasmine rice starches decreased with increasing moisture level of the treatments. In contrast, the RC of the treated Chiang rice starch remained practically unchanged. A peak of crystalline V‐amylose‐lipid complexes was clearly presented in all treated Chiang rice starches. The peak became progressively stronger with increasing moisture level of the treatment. Differential scanning calorimetry (DSC) of all treated rice starches showed a shift of the gelatinization temperature to higher values. Increasing moisture level of the treatments increased the onset gelatinization temperature (T_o) but decreased the gelatinization enthalpy (ΔH) of rice starches. A broad gelatinization temperature range (T_c‐T_o) with a biphasic endotherm was found for all treated Chiang rice starches and Jasmine rice starch after HMT₂₇ (HMT at 27% moisture level). Additionally the (T_c‐T_o) of treated Chiang rice starches increased linearly with increasing moisture level of the treatments.     

Effect of dietary lipid sources on odour‐active compounds in muscle of turbot (Psetta maxima)

Odour‐active compounds in muscle of turbot (Psetta maxima) fed experimental diets containing fish oil (FO), soybean oil (SO) or linseed oil (LO) were investigated by a gas chromatography/olfactometry technique. Thirty‐one areas associated with odours were detected in muscle extracts. Among the compounds responsible for these odours, 23 were formed by oxidation of unsaturated fatty acids. Independently of diet, (E)‐2‐penten‐1‐ol and (E)‐3‐hexen‐1‐ol contribute strongly to the odour of turbot. (E,Z)‐2,6‐Nonadienal, (E)‐2‐pentenal and (E,E)‐1,3‐(Z)‐5‐octatriene seem to contribute strongly to the odour of turbot fed diets containing high levels of n‐3 PUFA (FO and LO groups). Hexanal and decanal show a high detection frequency in turbot fed diets containing vegetable oils. Odorous compounds which are not formed by lipid oxidation (methional, 1‐acetyl pyrazine, 4‐ethyl benzaldehyde and 2‐acetyl‐2‐thiazoline) were not affected by dietary lipid sources. © 2001 Society of Chemical Industry     

MIM零件烧结过程中收缩和变形的数值模拟

为描述金属粉末注射成形坯件在烧结过程中的收缩和变形行为,基于连续介质力学原理建立了符合粘塑性本构关系的宏观烧结模型。该模型通过有限元软件Abaqus的用户子程序实现,进行烧结过程的数值模拟。分析了由于坯件重力、非均匀初始密度分布以及坯件支承体之间的摩擦力等因素而引起的非均匀收缩和变形。通过与试验结果的比较,验证了烧结模型和数值方法的正确性。     

American = White?

Six studies investigated the extent to which American ethnic groups (African, Asian, and White) are associated with the category "American." Although strong explicit commitments to egalitarian principles were expressed in Study 1, Studies 2-6 consistently revealed that both African and Asian Americans as groups are less associated with the national category "American" than are White Americans. Under some circumstances, a dissociation between mean levels of explicit beliefs and implicit responses emerged such that an ethnic minority was explicitly regarded to be more American than were White Americans, but implicit measures showed the reverse pattern (Studies 3 and 4). In addition, Asian American participants themselves showed the American = White effect, although African Americans did not (Study 5). The American = White association was positively correlated with the strength of national identity in White Americans. Together, these studies provide evidence that to be American is implicitly synonymous with being White. (PsycINFO Database Record (c) 2010 APA, all rights reserved)