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991.
Lattice lines with 1.1 nm and 0.55 nm spacings were resolved in isotactic polystyrene (i-PS) single crystals using a conventional transmission electron microscope, equipped for low dose imageing. It is suggested that these crystals may be used as a model for the direct imageing of structural defects in polymer crystals. 相似文献
992.
Electron-beam-induced current (EBIC) and secondary electron image (SEI) modes of a scanning electron microscope (SEM) are
utilized for characterization of charge collection inhomogeneities in hydrogenated amorphous silicon devices. These inhomogeneities
are due to such fabrication defects as substrate surface roughness, pin holes, blistering and lift-off. SEM observations are
correlated with the electrical properties of the devices. Electronirradiation-induced damage in these devices is also investigated
by measuring the EBIC time decay at continuous electron irradiation as a function of both the electron -beam energy and current.
This decay mechanism is based on the formation of electron-irradiation-induced microscopic defects that act as recombination
centers and reduce the lifetime of carriers. 相似文献
993.
994.
Certain failures in absorption and distillation columns are attributed to flow induced vibrations. Mechanisms by which column pressure pulsations can occur are discussed. The mechanism most closely linked to the damage conditions is identified and its limits and characteristics defined. Interaction between the pulsation phenomenon and the mechanical damage is discussed. 相似文献
995.
There are basically two approaches to the use of psychometric tests in the detection of "brain damage": the first is centred around a view of regional equipotentiality of brain functioning and the second around a unitary view of brain functioning. The former was explored in an earlier paper in this journal (Rubino, 1970). The latter approach is explored here in terms of the utility of three well-known tests: the Bender Gestalt, the Benton Visual Retention Test, and the Graham Kendall Memory for Designs. The influence of such factors as age, diagnoses, hit-rates, etc., are briefly discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
管银章 《江汉石油职工大学学报》2004,17(5):44-45
发展是国企的"第一要务"。我们必须用实事求是的思想、原则、方法去研究、探索、指导企业的发展,推动"第一要务"目标的实现。践行实事求是思想,要求深入调查研究企业发展过程中的实际情况和深层次问题,保持与时俱进和持续创新的精神,不断强化务实、勤政和亲民意识,塑造经营管理者的良好形象。 相似文献
997.
Kjaergaard SK Hempel-Jørgensen A Mølhave L Andersson K Juto JE Stridh G 《Indoor air》2004,14(3):200-207
The population distributions of CO(2)-induced irritation sensitivity in the eyes (COI), tear film stability (break-up time, BUT), and epithelium damage (ED) and the relation of these to basic potential confounders were assessed in an age- and gender-stratified random sample of citizens in Aarhus County, Denmark. One hundred eighty-two non-allergic, non-smoking persons participated. A general health questionnaire and an indoor air questionnaire was filled out before the measurements. The BUT was non-normally distributed, as was COI at 16% CO(2) and single ED-scores. However, COI average for all levels was normally distributed and the total score for ED was only marginally deviating. BUT decreased, the threshold to CO(2) increased, and irritation intensity at CO(2) eye exposure decreased with increasing age. ED was increased among women. There were no internal relations between the three measures, but reduced BUT was seen among subjects rating high levels of exposure to dust, electrostatic fields, and dry air. ED decreased by perceived unpleasant odors and increased with experiences of high temperatures. CO(2) sensitivity increased by perceived draught, dry air, and noise exposure prior to measurements. Selection bias cannot be excluded and the results may therefore not be truly representative of the general population. However, the results may be used as reference data for future use of measurements of break-up time, epithelium defects, and CO(2) sensitivity of the eyes in the indoor air. PRACTICAL IMPLICATIONS: The most direct implication is that results can be used as reference level for measurements in problem buildings and for individual measurements. The reference can also be used in research and the other results as basis for future hypotheses and for support of existing hypotheses. 相似文献
998.
轮南油田注水井污染评价方法探讨 总被引:4,自引:2,他引:2
基于塔里木盆地轮南油田注入水对油藏污染的特点,定义注水井的实际注水量(Qt)与理论吸水量(Qf)之比为注水井吸水效率(α),根据α随注水时间(t)的变化所反映的地层污染的变化情况,将地层的污染程度分为无污染(α≥1.0)、轻微污染(0.9≤α<1)、一般污染(0.7≤α<0.9)和严重污染(0≤α<0.7)。α-t曲线可以反映不同注水时期注水井的地层污染状况,间接了解注水水质的变化情况;Qt-Qf图示法能直观反映较长注水时期内注水井的总体污染状况。与通常采用的"表皮系数"法(只能评价注水井在较短时间段内的污染状况,且获取参数成本高)相比,所提出的评价方法具有获取参数容易、分析简单、结果直观的优点,便于监测注水井注入水对地层的污染状况,及时发现注水井的水质问题。图3表3参5 相似文献
999.
1000.
I. A. Perminov V. G. Orlik 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2003,37(3):175-178
A method for diagnosing mechanical damage and wear of the blade system and the shroud, diaphragm, and end seals is presented. The method is based on the use of the readings of devices for scheduled control of the steam temperature and pressure at the outlet from the cylinders, in the extracted steam, and in the first shoulders of the end seals. Results of practical application of the method at electric power plants including those equipped with data-processing equipment are presented. The introduction of the suggested monitoring will make it possible to pass from scheduled repair to determining the repair time proceeding from the actual condition of the turbine. 相似文献