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41.
Stress migration lifetime is characterized for a CoWP-only cap process (i.e., no dielectric cap) and a CoWP + SiN cap process. For the CoWP-only process, the stress migration lifetime depends on the CoWP thickness. In order to achieve a long stress migration lifetime, the CoWP must be sufficiently thick to protect the Cu during the via etch and strip processes. The data suggests that CoWP removal is enhanced beneath partially landed vias, resulting in reduced stress migration lifetime.  相似文献   
42.
Examined parental competence-enhancing communication (CEC), which is transactional behaviors that may facilitate healthy child development. A set of coding categories was applied to Rorschach protocols from both parents of 61 10-yr-old boys who were at risk for the development of psychopathology; a parent in each family had previously been hospitalized for a mental disorder. Teacher and peer ratings of the children were also obtained. On the individual Rorschach, parents of well-adjusted children made clear transitions to each new percept and gave responses freely. These features of parental CEC were independent of parental psychopathology. CEC, symptomatic, and pathogenic communication seem to be separate domains of parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
Oxygen desaturation occurs during sleep in many patients with chronic obstructive lung disease (COLD) and is often caused by sleep-disordered breathing (SDB). Nocturnal oxygen therapy should improve nighttime hypoxemia, but might also worsen SDB. Using standard polysomnographic techniques, we evaluated the frequency and duration of oxygen desaturation and SDB during sleep in 11 patients with stable COLD. During half of the night the patients breathed air through a nasal cannula and during the other half of the night they breathed oxygen at 2 liters per minute. Five patients had arterial lines inserted for determination of arterial blood gas levels during periods of SDB or desaturation. The ten men and one woman slept 70 minutes (52 percent of time in bed) while on air and 111 minutes (80 percent of time in bed) while on oxygen (p < 0.001). Oxygen therapy reduced the number of episodes of desaturation per hour and the time spent in desaturation. However, there was no difference between air and oxygen in episodes of SDB per hour, the duration of episodes of SDB, baseline sleeping PaCO2 or PaCO2 during episodes of desaturation or SDB. Therefore, in most patients with stable COLD, administration of oxygen at 2 liters per minute improves oxygenation, prolongs sleep, but does not adversely affect SDB.  相似文献   
44.
The polyphenolic content of the testa of two coloured flower varieties of beans grown in Wales was comparable with that of two coloured flower varieties of peas grown in eastern England. Testa tannins from both species had the same adverse effect on protein solubility, the inclusion of 15% testa producing a 7 unit reduction in protein solubility in 5% saline solution. Water extracts prepared from the testas also significantly inhibited in vitro the activities of trypsin, α-amylase and fungal cellulase, and in all cases enzyme activity was restored on the addition of polyvinyl pyrrolidone, clearly indicating that the observed inhibition was due to the presence of tannins. Analysis of the whole grain revealed that, due to differences in the proportion of testa (approximately 13% in beans as compared with 10% in peas), peas had a significantly lower overall polyphenolic content. However, it is concluded that pea testa tannins may be of equal significance to bean tannins in animal diets since the formulation of isonitrogenous diets would require a greater proportion of peas due to their lower protein content.  相似文献   
45.
We show that nanoporous anodic alumina films, with pore diameters in the range 10-80 nm, can be transformed from being very hydrophilic (or super-hydrophilic) to very hydrophobic (or super-hydrophobic) by coating the surface with a thin (2-3 nm) layer of a hydrophobic polymer. This dramatic transformation happens as a result of the interplay between surface morphology and surface chemistry. The coated surfaces exhibit 'sticky' hydrophobicity as a result of ingress of water into the pores by capillary action. The wetting parameters (contact angle and contact angle hysteresis) exhibit qualitatively different dependences on pore diameters in coated and uncoated films, which are explained by invoking appropriate models for wetting.  相似文献   
46.
Eighteen bulbs of each of four cultivars and two inbred lines of swede (Brassica napus ssp rapifera L) were harvested at monthly intervals from 25 July 1988 to 6 March 1989. On average, dry-matter yield increased from 50.8 to 277.0 g plant?1 by 14 November and then slowly fell to 240.5 g plant?1 on 6 March; and dry-matter content rose from 99.5 to 118.9 g kg?1 fresh weight on 19 September and then slowly declined to 99.0 g kg?1 fresh weight in March. Hardness also increased from 25 July to 19 September but then remained constant. A hard high-dry-matter line, BWc4hca, and a soft lowdry-matter line, CRdagaa, were the extremes for changes in sugar content. From July to October the average contents in g kg?1 DM of BWc4hca and CRdagaa were respectively: fructose 146.8, 224.3; glucose 206.8, 293.7; and total 390.7, 543.9. In contrast, from November to March their contents were much closer: fructose 187.9, 209.9; glucose 314.7, 323.I; and total 534.4, 549.3. Sucrose levels were much lower and more variable, but overall BWc4hca was highest, 34.1, and CRdagaa lowest, 20.6. The implications for swede breeding are discussed.  相似文献   
47.
The author's work on the incorporation of phthalocyanines into inorganic polymers is reviewed. The synthesis of poly(siloxane phthalocyanines) and the synthesis and characterization of fluoro(phthalocyanine) Group III compounds and their conducting derivatives are described.  相似文献   
48.
The ratio of B to C hordeins was determined using high performance liquid chromatography (h.p.l.c.) for a range of spring barley cultivars and the values obtained varied from 1.79 for Kneifel to 4.15 for Goldmarker. Fine grinding of seed samples resulted in a significant increase in the quantity of protein solubilised but relatively little difference was observed in the B and C hordein ratio, which appeared to be independent of protein extraction efficiency. Increased nitrogen content significantly changed the ratio by increasing the proportion of C hordein. A highly significant correlation was found between the B and C hordein ratio and sample nitrogen content. Analysis of single seeds selected at random from within a single sample of Goldmarker revealed considerable variability in the B and C hordein ratios with values differing by over 2 units. Due to the sensitivity of the B to C hordein ratio to various environmental effects, it is unlikely that the ratio will be of great value as an unambiguous aid in the identification of barley cultivars.  相似文献   
49.
The effect of forward and reverse torsion on flow behavior and microstructure evolution, particularly dynamic and static spheroidization, on Ti-6Al-4V with an alpha lamella colony microstructure was studied. Testing was undertaken sub beta transus [1088 K (815 °C)] at strain rates of either 0.05 or 0.5 s?1. Quantitative metallography and electron back scatter diffraction has identified that a critical monotonic strain (ε c) in the range of 0.3 to 0.6 is required to initiate rapid dynamic spheroidization of the alpha lamella. For material deformed to strains below ε c and then reversed to a zero net strain the orientation relationships between alpha colonies are close to ideal Burgers, enabling prior beta grains to be fully reconstructed. Material deformed to strains greater than ε c and reversed lose Burgers and no beta reconstruction is possible, suggesting ε c is the strain required to generate break-up of lamella. Static spheroidization is, however, sensitive to strain path around ε c. Annealing at 1088 K (815 °C) for 4 hours for material subjected to 0.25 forward + 0.25 forward strain produces 48 pct spheroidized grains while material with 0.25 forward + 0.25 reverse strain has 10 pct spheroidization. This is believed to be a direct consequence of different levels of the stored energy between these two strain paths.  相似文献   
50.
Tubers from six cultivars selected on the basis of their rates of glycoalkaloid accumulation in response to light exposure were stored at 10, 7 and 4°C. After 9 weeks at 10°C a subset from each cultivar was removed and subsequently stored at lower temperatures. Samples were removed after 9, 18 and 24 weeks storage and analysed for their glycoalkaloid content. At all temperatures the rate of glycoalkaloid accumulation was independent of the level found at harvest and significant interactions were found between cultivar and temperature. The highest rates of accumulation were seen in tubers from the cultivars Brodick and Pentland Crown stored at 4°C. During the first 9 weeks of storage at this temperature the glycoalkaloid content of these two cultivars increased by 7·4 and 19·1 mg per 100 g fresh weight respectively and thereafter remained constant. At 7°C glycoalkaloid content tended to increase more rapidly than at 10°C with again the greatest increases being found for Brodick and Pentland Crown. In the case of the former glycoalkaloid content increased linearly during the 24 weeks of the experiment but the glycoalkaloid content of Pentland Crown tubers stored at 7°C increased rapidly in the first 9 weeks and thereafter increased more slowly, reaching a final value which exceeded the recommended maximum glycoalkaloid concentration for human consumption by 50%. Cultivars which did not accumulate glycoalkaloids rapidly in response to light exposure were the most stable and least sensitive to storage temperature. Tubers transferred to colder conditions nine weeks after storage at 10°C did not accumulate glycoalkaloids at a similar rate to those placed in similar conditions soon after harvest. © 1997 SCI  相似文献   
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