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61.
The literature on the relationships between lichens and air pollution is reviewed, with particular reference to the development of the concepts governing their use as indicators of air pollution levels. Lichens are particularly sensitive to sulphur dioxide which acts by the destruction of chlorophyll. By considering both the species present and their abundance, zones indicative of mean air pollution levels can be quickly mapped. The way in which some species respond in different regions varies and so zonal scales can only be reliably applied in the areas where they were devized. Only in a few cases has it been possible to correlate lichen zones with particular sulphur dioxide concentrations, principally because of a lack of physicochemical measurements; but even where such correlations are not possible, lichen zones provide a rapid qualitative means of assessing the effects of air pollution. Maps showing the type of data obtained by this method are presented, and a table summarizes the published work on major cities, towns, industrial plants, and in larger geographical regions.  相似文献   
62.
This paper provides a graphical approach for presenting results of a statistical test of average equivalence with process data. In addition, a graphical representation of process change in variance is presented. An example from the biopharmaceutical industry is provided to illustrate the information contained in the chart. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
63.
Objective: To determine the relationship between length of time spent expressing highly aroused emotion and therapeutic outcome. Method: Thirty-eight clients (14 male, 24 female) between the ages of 22 and 60 years (M = 39.5, SD = 9.71), treated for depression with experiential therapy, were rated on working alliance and expressed emotional arousal (with the Client Expressed Emotional Arousal Scale) in their three highest arousal sessions. Among the clients, 34 were of European ethnicity, 2 were of Asian ethnicity, 1 was of Latino ethnicity, and 1 was of Caribbean–Canadian ethnicity. Clients were administered the short form of the Working Alliance Inventory following their 4th therapy session and also completed, pre- and posttherapy, the Beck Depression Inventory (BDI), the Global Severity Index (GSI) of the Symptom Checklist–90–Revised (SCL-90-R), the Inventory of Interpersonal Problems, and the Rosenberg Self-Esteem Scale. Results: Hierarchical regressions showed that a nonlinear pattern of expressed emotional arousal predicted outcome significantly above the alliance. This combination predicted 30% of outcome variance on the BDI and 24% on the GSI (p  相似文献   
64.
65.
The gasification of pine and mixed-hardwood chips has been carried out in a pilot-scale system at a range of gas flow rates. Consuming ∼17-30 kgh−1 of feedstock, the producer gas was composed of ∼200 dm3 m−3 carbon monoxide, 12 dm3 m−3 carbon dioxide, 30 dm3 m−3 methane and 190 dm3 m−3 hydrogen, with an energy content of ∼6 MJ m−3 for both feedstocks. It was found that the efficiency of the system was enhanced at higher flow rates.  相似文献   
66.
There is a need for next-generation, high-performance power electronic packages and systems utilizing wide-band-gap devices to operate at high temperatures in automotive and electricity transmission applications. Sn-3.5Ag solder is a candidate for use in such packages with potential maximum operating temperatures of about 200°C. However, there is a need to understand the thermal cycling reliability of Sn-3.5Ag solders subject to such high-temperature operating conditions. The results of a study on the damage evolution occurring in large-area Sn-3.5Ag solder joints between silicon dies and direct bonded copper substrates with Au/Ni-P metallization subject to thermal cycling between 200°C and 5°C are presented in this paper. Interface structure evolution and damage accumulation were followed using high-resolution X-ray radiography, cross-sectional optical and scanning electron microscopies, and X-ray microanalysis in these joints for up to 3000 thermal cycles. Optical and scanning electron microscopy results showed that the stresses introduced by the thermal cycling result in cracking and delamination at the copper–intermetallic compound interface. X-ray microanalysis showed that stresses due to thermal cycling resulted in physical cracking and breakdown of the Ni-P barrier layer, facilitating Cu-Sn interdiffusion. This interdiffusion resulted in the formation of Cu-Sn intermetallic compounds underneath the Ni-P layer, subsequently leading to delamination between the Ni-rich layer and Cu-Sn intermetallic compounds.  相似文献   
67.
The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0–1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of (002), (110) and (020) decreased, the d-spacing of (200) increased, and the d-spacing of (310) varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased.  相似文献   
68.
The objective of this study was to investigate parenteral vitamin E for the prevention of peripartum disease in dairy cows. A randomized clinical trial was conducted in 21 commercial dairy herds. Cows (n = 1142) were randomly assigned to receive either a single subcutaneous injection of 3000 IU of vitamin E, or placebo, 1 wk before expected calving. Serum alpha-tocopherol was significantly increased in treated cows at 7 and 14 d, but not at 21 d after injection. Overall, there were no significant differences between treatment groups in the incidence of retained placenta, clinical mastitis, metritis, endometritis, ketosis, displaced abomasum, or lameness. However, there was a conditional benefit of treatment for reduction of the incidence of retained placenta. Cows with marginal pretreatment vitamin E status (serum alpha-tocopherol to cholesterol mass ratio < 2.5 x 10(-3)) that received an injection of vitamin E tended to have reduced risk of retained placenta. However, in cows with adequate serum vitamin E, there was no reduction in the incidence of any disease. For clinical application, primiparous animals were most likely to benefit from prepartum injection of vitamin E.  相似文献   
69.
70.
The resurgence of metal-on-metal articulating surfaces for hip arthroplasty has also heightened concerns about the degree and magnitude of metal particle generation and the accompanying increase in circulating metal ion concentrations. In this study, we measured the concentration of chromium in serum and urine and the concentration of cobalt in serum in twenty-five patients with modern metal-on-metal surface arthroplasty of the hip in a prospective manner. The results showed that the mean post-operative chromium in serum levels were 22-fold, 23-fold and 21-fold higher at 3, 6 and 12 months post-operative, respectively, than pre-operative levels. The mean post-operative cobalt in serum levels were 8-fold, 7-fold and 6-fold higher at 3, 6 and 12 months post-operative, respectively, than pre-operative levels. The mean post-operative chromium in urine levels were 9-fold, 10-fold and 14-fold higher at 3, 6 and 12 months post-operative, respectively, than pre-operative levels. The values seen in this study with the current generation of surface arthroplasties are: (a) lower than those seen in an earlier generation of surface arthroplasties; (b) in the same range as those observed in association with metal-on-metal conventional total hip replacements, which typically have smaller head sizes; (c) higher than values observed in patients with conventional metal-on-polyethylene articulating couples.  相似文献   
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