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A new method based on a two-wire line has been developed for noncontact diagnostics of a low-temperature plasma and its fluxes
in channels with complex profiles. This method provides good spatial and time resolution.
Pis’ma Zh. Tekh. Fiz. 23, 1–7 (July 26, 1997) 相似文献
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It is shown that, at thermodynamic equilibrium, the release of charge carriers from the localized states of bistable amphoteric centers into quasi-free states depends on the degree of compensation. This brings about different functional dependences of the concentration of free charge carriers on temperature. It is found that, in uncompensated semiconductors, the concentration of free charge carriers follows the same dependence in the case of bistable amphoteric centers and bistable amphoteric U ? centers, although the distributions of charge carriers over the charge states and configurations are different for these types of centers. The results can be used for interpreting various experimental data insufficiently explained in the context of the traditional approach. 相似文献
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Vjacheslav V. Zuev 《Journal of Polymer Research》2008,15(5):351-356
Functionalized polyanilines containing biphenyl, terphenyl, carbazole, anthracene, and 4-n-hexylphenyl moieties were synthesized though the reaction of polyaniline in emeraldine base form with sodium salt of corresponding
vinylketoaromatics with quantitative yields. Polymers were characterized with Fourier transform infrared spectroscopy, proton
nuclear magnetic resonance spectroscopy, and thermogravimetry. The emission characteristics of these polymers in N-methyl-2-pyrrolidone solution were examined. The functionalized polyanilines exhibited an intense green emission. 相似文献
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M. Hofbaur ÖVE N. Dourdoumas ÖVE 《e & i Elektrotechnik und Informationstechnik》1997,114(7-8):371-379
Qualitative-quantitative simulation is one of the most productive and promising research areas in Artificial Intelligence to emerge in recent years. This method provides an elegant way for an exhaustive analysis of uncertain dynamic systems. The application of the qualitative-quantitative simulation is shown in this paper. The important question about the stability of a quanlitatively described dynamical system is solved by a novel analytic method. 相似文献
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In order to determine the differences in histological grade of activity and the stage of fibrosis in patients with chronic liver diseases due to multiple hepatitis virus infection and single infection of HBV and HCV we assessed the 68 liver biopsies samples according to Knodell and Scheuer scoring systems. Retrospectively, 216 liver biopsies reports from consecutive patients with chronic viral hepatitis were analysed. Histological activity index (HAI) in HBV/HCV coinfection was higher than in a single HCV infection; it did not differ in groups of HBV/HBC and HBV. The difference was due to the interface hepatitis; lobular activity and portal inflammation were the same. In HDV superinfection HAI was high due to both portal-periportal and lobular hepatitis. HAI depended mainly upon the presence of HBV replication; in patients with chronic hepatitis C with HBV-DNA HAI was also higher than in single HCV group. No difference in HAI between triple and dual hepatitis virus infection was found. In patients with HBV/HCV coinfection and especially with HDV superinfection the advanced stages occurred more than often than in patients with single infections. 相似文献
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Autosomal dominant polycystic kidney disease (ADPKD) is a systemic disorder with a variety of cardiovascular manifestations. This study presents a group of patients with ADPKD who had intracranial arterial dolichoectasia. One hundred seventy-eight ADPKD patients were screened with magnetic resonance angiography, 40 ADPKD patients had conventional angiography, and 98 ADPKD patients underwent a brain autopsy. For comparison, 360 patients without ADPKD who had magnetic resonance angiography and conventional angiography or brain autopsy were also studied. The prevalence of asymptomatic intracranial arterial dolichoectasia was 2.2% (4 of 178), 2.5% (1 of 40), and 2.0% (2 of 98) in the three ADPKD groups, respectively. None of the patients without ADPKD had intracranial arterial dolichoectasia. In addition to the seven patients with asymptomatic disease, two ADPKD patients with vertebrobasilar dolichoectasia had posterior circulation ischemic symptoms. The mean age of the nine patients (five men and four women) was 56.6 yr (range, 41 to 67 yr). The posterior circulation was involved in five patients, the anterior circulation was involved in two patients, and both were involved in two patients. Arterial dissection was believed to have caused middle cerebral artery dolichoectasia in one patient, and intracranial arterial dissections were strongly suspected in two other patients. Six of the nine patients with intracranial arterial dolichoectasia had additional vascular manifestations of ADPKD. Some patients with ADPKD are at an increased risk of developing intracranial arterial dolichoectasia and dissections. Recognizing this association is important because (1) it may be a cause of stroke; (2) it may mimic a saccular aneurysm on radiographic studies; and (3) it suggests that the arteriopathy of ADPKD may be more generalized than previously believed. 相似文献
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