Fabrication and characteristics of tapes and test magnets made from Ag-Clad Bi-2223 superconductors

Pb_0.4Bi_1.8Sr₂Ca_2.2Cu₃O_x (Bi-2223) precursor powder was prepared by a solid-state reaction of carbonates and oxides of lead, bismuth, strontium, calcium, and copper, and the powder was then used to fabricate silver-clad tapes by the powder-in-tube technique. Transport critical current density (J_c) values>4×10⁴ A/cm² at 77K and 2×10⁵ A/cm² at 4.2 and 27K have been achieved in short tape samples. Long lengths of tape were tested by winding them into pancake coils. Recently, we fabricated a test magnet by stacking ten pancake coils, each containing three 16m lengths of rolled tape, and tested it at 4.2, 27 and 77K. A maximum generated field of 2.6 T was measured in zero applied field at 4.2K and the test magnet generated significant self-field in background fields up to 20 T. The results are discussed in this paper.     

Occupational stress: Its causes and consequences for job performance.

Examined occupational stress and its relation with individual characteristics, job conditions, stressful events, affect, and job performance. Study 1, in which 104 nurses participated in group discussions and 96 nurses (mean age 36 yrs) completed a questionnaire, identified 45 stressful events (appended) for nurses. In Study 2, 171 nurses (mean age 34.6 yrs) completed another questionnaire and were rated by a supervisor and/or a coworker. Findings show that ratings of interpersonal aspects of job performance (i.e., sensitivity, warmth, consideration, tolerance) and cognitive/motivational aspects (i.e., concentration, composure, perseverance, adaptability) correlated significantly with self-reported perceptions of stressful events, subjective stress, depression, and hostility. Models developed through path analysis suggest that the frequency and subjective intensity of the 45 events identified in Study 1 caused feelings of stress, leading to depression and causing decrements in interpersonal and cognitive/motivational aspects of job performance. (43 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex role orientation and behavior in a work setting.

Examined the possibility that androgynous persons might respond more favorably and supportively toward persons in jobs unusual for their sex. 38 female and 27 male low- to middle-level managers completed the Bem Sex-Role Inventory and were rated by their supervisors for behavioral dispositions related to showing support toward persons in nontraditional jobs, candor and personal assertiveness, acceptance of nontraditional job change, and active listening. Highly androgynous Ss showed more acceptance of nontraditional job change, support for persons in nontraditional jobs, and active listening. After controlling for masculinity and femininity scores, androgyny scores still contributed to explained variance in acceptance of nontraditional job change but not in support for persons in nontraditional jobs or active listening. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interpersonal facilitation and job dedication as separate facets of contextual performance.

This study attempts to refine the construct of contextual performance by dividing it into 2 narrower constructs, interpersonal facilitation and job dedication. Supervisors rated 975 U.S. Air Force mechanics on at least 1 of 4 aspects of job performance (different supervisors rated each aspect of performance), and 515 of these mechanics also completed self-report individual difference measures. Correlations between performance ratings and individual difference variables support distinguishing task performance from interpersonal facilitation but not from job dedication. Thus this study suggests the need to redefine task performance to include motivational elements of job dedication. Then task performance would include task proficiency and motivation to perform one's own tasks effectively, and contextual performance would include interpersonal skills, the motivation to maintain good working relationships and help others perform their tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recent advances in bismuth-based superconductors

Significant progress has been made in the development of high-critical-temperature (high-T_c) mono- and multifilament bismuth-based superconductors by the powder-in-tube (PIT) technique. High critical current density (J_c) has been achieved in both short- and long-length monofilament conductors. J_cs up to 1.2 × 10⁴ A/cm² were achieved in an 850 m long multifilament conductor. Pancake-shaped coils and test magnets, fabricated from long conductors, were characterized at various temperatures and applied magnetic fields. One such magnet containing 480 m of high-T_c tape generated a record-high field of 2.6 T at 4.2 K. Multifilament conductors appear to possess better mechanical properties and retain a higher percentage of their initial critical current under strain than monocore conductors, which is important for practical considerations. PIT processing of superconducting tapes with Ag-Al₂O₃ as the sheath material is perhaps another route to improve mechanical properties.     

Liking and attributions of motives as mediators of the relationships between individuals' reputations, helpful behaviors and raters' reward decisions.

Two studies investigated the mediating effects of liking and attributions of motives on the relationship between a ratee's reputation and helpful behaviors and raters' reward decisions. During managerial simulations, raters evaluated individuals after watching videotapes in which the individual's reputation and helpful behaviors were manipulated. Results indicated an interaction effect between reputation and helpful behaviors such that a helpful person with a good reputation received more rewards than did a helpful person with a bad reputation. In contrast, an unhelpful person with a good reputation did not receive better rewards than an unhelpful person with a bad reputation. Moreover, raters' liking of ratees and the motives raters attributed to ratees' helpful behaviors mediated the relationship between the manipulations and raters' reward decisions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)