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61.
The influence of convective heat transfer on constant current density anodizing of aluminium in sulfuric acid has been examined in a wall-jet electrode reactor. The uniformity of the anodic film thickness is related to the local electrode temperature distribution, which is dependent on the convection. The higher the local temperature, the greater the local oxide thickness. An increased local temperature enhances local field assisted oxide dissolution at the pore bases, and consequently acts to increase the local current density. At relatively high current densities, local features develop on the electrode surface, accompanied by high initial, local temperature rises. The relevance of such local features, limiting useful oxide growth, is considered further. 相似文献
62.
Thompson Robert J.; Gil Karen M.; Keith Barbara R.; Gustafson Kathryn E.; George Linda K.; Kinney Thomas R. 《Canadian Metallurgical Quarterly》1994,62(4):856
Rates of poor psychological adjustment of children with sickle cell disease remained relatively constant over initial and follow-up assessment points. 50 children (aged 7–12 yrs) and their mothers completed the initial protocol. 30 children completed the follow-up plus 5 additional children and their mothers. These Ss were aged 7–24 yrs at follow-up. With initial levels of adjustment controlled, children's strategies for coping with pain accounted for a significant increment in child-reported symptoms and mother-reported internalizing behavior problems at follow-up beyond the contribution of illness and demographic parameters and follow-up interval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In contrast to D. C. Zuroff, M. Mongrain, and D. A. Santor (2004), the current authors find the promissory note of dependency-sociotropy (DEP-SOC) and self-criticism-autonomy (SC-AUT) as a model of risk for depression to be in default. The authors propose reorganizing what has been cast as unitary effort into 3 distinct endeavors: a psychoanalytic clinical theory, development of a refined empirical model of risk for clinical depression, and research examining the effects of DEP-SOC and SC-AUT on interpersonal relationships in nonclinical samples. The authors identify some issues that need to be accommodated regardless of whether the assessment of Zuroff et al. (2004) or their own is accepted. DEP-SOC and SC-AUT are best construed as correlated, continuous dimensions. Future work also needs to accommodate depression as chronic recurrent condition, advances in developmental psychopathology, and more stringent criteria for positing a risk factor for clinical disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
NE Taylor RN Rosenthal B Chabus S Levine AS Hoffman J Reynolds L Santos I Willets P Friedman 《Canadian Metallurgical Quarterly》1993,15(1):36-40
Cryptococcal meningitis has a high mortality rate of central nervous infection. The patients usually die of the disease itself, or complications from increased intracranial pressure. Early diagnosis and treatment, including surgical drainage, will improve the results. In this series, twenty-one patients with high intracranial pressure (ICP > 300 mmH2 O) are presented. Fourteen received implantation of Ommaya reservoir to aspirate cerebrospinal fluid (CSF) for relief of symptoms of ICP. Meanwhile 4 of these 14 patients also received intraventricular injection of amphotericin B because of poor response to systemic drugs. Another seven patient received systemic drug therapy only. Survival during therapy occurred in 11 of 14 patients in the surgical group, compared with only 1 of 7 patients treated by drug therapy alone (P = 0.019). In the 14 patients who received implantation of an Ommaya reservoir, there was one complication of CSF leakage when the reservoir ruptured because of repeated aspiration. For patients with cryptococcal meningitis with high ICP, early implantation of an Ommaya reservoir will improve the survival rate. 相似文献
67.
Mittenberg Wiley; Burton Donald B.; Darrow Evelyn; Thompson Garrie B. 《Canadian Metallurgical Quarterly》1992,4(3):363
The normative data provided in the Wechsler Memory Scale—Revised (WMS—R) manual for individuals aged 25–34 yrs were estimated statistically by interpolation. As an empirical check of this procedure, a representative stratified sample in this age range was selected to match the 1980 US Census data on relevant demographic characteristics. Prorated Full Scale IQs for the group were normally distributed, having a mean of 101.3 (SD?=?14.58, range?=?72–231). Differences between the empirically derived and published index scores appeared to be clinically significant. Substantial intra-individual differences were common when Visual–Verbal or General–Attention/Concentration indexes were compared. Normative data for the WMS—R subtests, indexes, and distribution of differences between indexes is provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
The inner filter effect is observed in luminescence whenever a second substance is present that has absorptions which overlap the luminescence. This results in a diminution of the luminescence at those wavelengths and is generally observed in solution. In the present communication we show that this effect can be observed when a solid rare earth complex is physically mixed with a solid luminescent organic matrix with which it does not interact. The resulting luminescence is reduced in emission intensity at those wavelengths corresponding to the absorptions of the rare earth ion. This is illustrated with a mixture of Na3[Ho(ODA)3] ·2NaClO4·6H2O and pyrene at 77 K, and it is shown that the absorption spectrum of the holmium complex can be extracted from the luminescence spectrum of pyrene. This absorption spectrum is in good agreement with that obtained by conventional spectroscopy with a single crystal. 相似文献
69.
David C. Apperley Robin K. Harris Gregory L. Marshall Derek P. Thompson 《Journal of the American Ceramic Society》1991,74(4):777-782
The 29 Si MAS NMR spectra of the 2H, 4H, 6H, and 3C polytypes of silicon carbide are presented. An attempt is made to correlate differences in the chemical shifts with local atomic environment. The results of the analysis of the spectra of pure polytypes are used as a basic for the interpretation of the spectra of mixed polytypes and a discussion of the crystallinity and impurity levels of different samples. Carbon-13 chemical shifts obtained from spectra of the same polytypes are also tabulated. 相似文献
70.