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排序方式: 共有287条查询结果,搜索用时 31 毫秒
31.
Demetriou Andreas; Efklides Anastasia; Papadaki Maria; Papantoniou Georgia; Economou Andreas 《Canadian Metallurgical Quarterly》1993,29(3):480
Investigated the structure and development of causal–experimental thought. 260 Ss (aged 12–16 yrs) were examined by 3 test batteries. The batteries involved items addressing combinatorial, hypothesis handling, experimentation, and model construction abilities. Confirmatory factor analysis indicated that these abilities, although distinct from each other, do share a common functional core, and they are organized in a higher order causal–experimental specialized structural system. Rasch scaling indicated that these 4 kinds of abilities follow overlapping developmental trajectories. Saltus modeling suggested that development is continuous rather than discontinuous. Individual differences were found in the rate of acquisition but not in the structure of abilities. A model of synergic developmental causality was proposed to account for this pattern of development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Gelso Charles J.; Prince Jeffrey; Cornfeld Janet L.; Payne Anna Beth; Royalty Georgia; Wiley Mary O'Leary 《Canadian Metallurgical Quarterly》1985,32(3):339
Compared the quality of 15 doctoral-level counselors' written evaluations following an initial interview with 113 17–36 yr old college students whose problems were judged to be primarily vocational, personal, or a mixture of the two. Overall, quality of intake evaluations was lower for vocational than for personal problems. Counselors' interest in doing intakes, studying the results of interest inventories, and doing vocational personal counseling related to the quality of their intake evaluations in various ways. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Ss received series of electric shocks to the forearm in which the temporal schedule and the sequence of shock intensities were associated with varying levels of randomness or uncertainty. The Ss were permitted an instrumental response which produced, in advance, information concerning 1 or both of these aspects of the shocks. Such information functioned as a strong positive reinforcement for most Ss. Instrumental response rate was a significant increasing function of the degree of uncertainty associated with the shock series, and occurred significantly more often for information concerning the temporal occurrence of shock than for its intensity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Blackburne-Stover Georgia; Belenky Mary F.; Gilligan Carol 《Canadian Metallurgical Quarterly》1982,18(6):862
Investigated the relationship between cognitive development, as measured by changes in the Moral Development Scale, and long-term reconstructive memory in 24 15–33 yr old females. The hypothesis that the past is reconstructed to conform with current developmental stages was examined. Results indicate that when developmental gains were made over a 1-yr interval, Ss used a higher stage perspective to reconstruct the decision making involved in resolving a problematic pregnancy and, hence, reconstructed the events in different terms than were originally presented. When developmental gains were not made over a 1-yr interval, Ss reconstructed the events in the same terms as originally presented. Further analysis indicated that those Ss who made developmental gains also referred to a phenomenon of "memory loss." Results support the hypothesis that memory is reconstructive rather than reproductive. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Gyorky Zsuzsanna K.; Royalty Georgia M.; Johnson Deborah Hazel 《Canadian Metallurgical Quarterly》1994,25(1):50
Investigated the use of brief therapy in university counseling centers with time-limited therapy (TLT) policies and centers without time limits (TUT). The Counseling Duration Questionnaire was mailed to 265 members of the Association of University and College Counseling Center Directors. 213 directors (80%) completed the questionnaire. TLT centers had longer waiting lists and more frequently referred clients to other mental health agencies both at intake and at termination of treatment. Mean number of sessions per client did not differ by duration policy. A cross-validated stepwise discriminant function analysis significantly differentiated TLT centers from TUT centers on the basis of several variables, including average size of December and April waiting lists and the percentage of enrolled students seen. The results raise concerns about generally accepted rationales for movement to time limits. Policy implications for administrators are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
36.
Eleni Loizou Popi Nicolaidou Kanari Georgia Kyriacou Maria Aletrari 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,16(1):459-463
Directive 98/83/EC concerning the drinking water quality and Directive 80/777/EC for Natural Mineral Water demand strict control
and monitoring for the presence of metals. The State General Laboratory as the official control laboratory (Accredited by
ISO 17025:2005) implements a national monitoring program in order to ensure that the drinking and natural mineral water quality
satisfy the requirements of the respective Directives. The National Monitoring program covers mainly metals such as Pb, Cd,
Cr, Ni, As, Se, Sb, Hg, Mn, Cu, Fe, Al and B in water supplied for human consumption either by distribution networks, vending
machines, mobile water containers, ground water intended for human consumption as well as bottled water. The determination
of metals in water by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) is a technique that successfully meets the requirements
of the above Directives as it is a very powerful tool for the measurement of metals at very low concentrations with high accuracy
and precision. The results obtained indicate that metal concentrations in drinking and bottled water examined were by far,
below the acceptable legal limits and even below the relevant detection limits. However, in samples of bottled natural mineral
water, high boron concentration were determined and risk assessment was performed due to the absence of relevant legal limits.
The present paper demonstrates the steps undertaken by the General Water Analysis Laboratory of the SGL for the validated
method used by ICP-MS in the determination of trace metals including boron in drinking and bottled water. 相似文献
37.
38.
Georgia Christopoulou Farid Modarresifar Benjamin L. Allsopp Alan H. Jones Paul A. Bingham 《Journal of the American Ceramic Society》2019,102(1):508-523
The crystallization mechanisms and elemental stability of leucite and kalsilite formed from K2O-Al2O3-SiO2 glasses were investigated by X-ray powder diffraction (XRD), X-ray fluorescence (XRF), Raman spectroscopy and differential scanning calorimetry (DSC). Glass samples with compositions along the leucite-kalsilite tie-line were produced by melt processing and were then heat-treated at 850, 950, and 1250°C for times ranging from 5 minutes to 1000 hours. Kalsilite is an unstable phase that behaves as an intermediate precursor to leucite. Crystalline materials in which kalsilite is the major phase lose potassium upon prolonged heat treatment (1000 hours at 1250°C), in contrast to those with leucite, in which little or no compositional alteration is detected. The formation of leucite from stoichiometric kalsilite is accompanied by the formation of potassium-doped alumina. The activation energies for leucite and kalsilite crystallization, determined via application of the Kissinger equation to thermal analysis data, were 579 and 548 kJ/mol, respectively. Finally, production of pure leucite can be achieved with more favorable crystallization kinetics when starting with off-stoichiometric compositions. 相似文献
39.
40.
Georgia N Tomara Panagiota K Karahaliou Dimitris L Anastassopoulos Stavroula N Georga Christoforos A Krontiras Jozsef Karger‐Kocsis 《Polymer International》2019,68(5):871-885
Polyamide‐6 (PA‐6)/boehmite alumina (BA) nanocomposites were prepared via direct melt compounding. Structural, thermal and dielectric properties of ‘as‐received’ (including moisture) and ‘dried’ (thermally treated) specimens were examined. The BA nanofiller was homogeneously dispersed in the PA‐6 matrix. XRD and FTIR revealed that crystallization of PA‐6 in the γ phase was favoured over α phase with increasing BA content. The crystallinity index (CI) and the percentage of α and γ phases were also evaluated. Dried specimens exhibited a lower CI than as‐received specimens while the CI decreased with the addition of filler. Broadband dielectric spectroscopy revealed the presence of γ, β and α relaxations, the Maxwell–Wagner–Sillars effect and the contribution of conductivity relaxation in the as‐received samples. The drying procedure unmasked a double feature of both β and α modes. The results of the complementary techniques were analysed and the effects of moisture and/or the incorporation of BA nanofiller on the microstructure of the PA‐6 matrix are disclosed. © 2019 Society of Chemical Industry 相似文献