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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A. E. Bohe J. J. Andrade Gamboa E. M. Lopasso D. M. Pasquevich 《Journal of Materials Science》1996,31(13):3469-3474
A chlorination process for recovering Zr from zircaloy scrap has been studied. Zircaloy chlorination was possible at temperatures as low as 220 °C. The scale microstructure and its effect on the zircaloy reactivity was analysed using Thermogravimetric analysis (TGA), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDXS) and scanning electron microscopy (SEM) techniques. A solid-solid phase transformation took place into the oxide scale during the zircaloy chlorination. Zirconium, as ZrCl4(g), was separated from the oxide scale and chlorides of Cr and Fe. The effect of the reaction temperature was also analysed. 相似文献
992.
R.M. Scanlan W.A. Barletta D. Dell'Orco A.D. McInturff A. Asner E.W. Collings P.F. Dahl H. Desportes A. Devred R. Garre E. Gregory W. Hassenzahl M. Lamm D. Larbalestier D. Leroy P. McIntyre J. Miller T. Shintomi H. ten Kate S. Wipf 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):544-554
993.
994.
995.
Experiments conducted at ground stations of the Quasar satellite communication network using both a null base as well as a
base of around 2000 km is described. In experiments with a null base, the time scale transmission error was 1 nsec. Comparison
of the results of collocation with data cbtained by the GLONASS system in the course of experiments using a 2100-km base demonstrated
a divergence of the results of from 5 to 25 nsec.
Translated from Izmeritel'naya Tekhnika, No. 4, pp. 35–38, April, 1996. 相似文献
996.
K. O. Sabdenov 《Combustion, Explosion, and Shock Waves》1993,29(5):568-576
The laminar flame theory under the condition of minimum entropy production is presented. The equation of the temperature boundary
layer is obtained for Le=0, and its general solution is found. It is shown that the mechanism of laminar flame propagation
can be treated from the viewpoint of stationary thermal explosion in a cylindrical vessel of radius 2 as the critical regime
in which the burnup is taken into account in an unusual form.
Tomsk. Translated from Fizika Goreniya i Vzryva, Vol. 29, No. 5, pp. 22–30, September–October, 1993 相似文献
997.
Myers Jerome L.; O'Brien Edward J.; Albrecht Jason E.; Mason Robert A. 《Canadian Metallurgical Quarterly》1994,20(4):876
Previous research demonstrated a contradiction effect: Although text currently being processed was locally coherent, readers were aware of inconsistencies between a protagonist's actions and characteristics of the protagonists that were described earlier in the text and subsequently backgrounded. In the present experiments, not only the critical characteristics but also the protagonist were backgrounded. When the protagonist was reintroduced into the narrative in the context of carrying out an inconsistent action, the contradiction effect again occurred. In Exps 1–3, we examined the effects of several variables on the onset of the effect. In Exp 4, we presented probes at various points in the passage with results that supported the conclusion that the critical characteristics had been backgrounded before the sentence that contradicted them. Results are discussed in terms of several recent models in which currently active representational elements serve as retrieval cues for other inactive, but highly related, elements. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
The equivalent series resistance and reactance of the electrode-electrolyte interface impedance have both been used to detect the onset of signal amplitude induced nonlinearity. Using a theoretical model, it is shown that the choice of the most sensitive indicator depends on the phase angle of the “polarization” impedance and on the applied frequency 相似文献
999.
Polyarteritis nodosa is a rare disorder and a form of systemic vasculitis. A 48 year-old female was admitted to the hospital because menorrhagia and pelvic pain in February 1993. The patient underwent exploratory laparotomy resulting in a total hysterectomy and bilateral salpingo-oophorectomy for myoma of uterus and a right adnexal cystic mass. Histopathologic examination revealed left ovarian periarteritis nodosa. Further investigation and 9 months follow-up failed to show any systemic involvement. To our knowledge the isolated ovarian polyarteritis nodosa is the first case in the literature. 相似文献
1000.
CD Hébert MR Elwell GS Travlos E Zeiger JE French JR Bucher 《Canadian Metallurgical Quarterly》1993,20(3):348-359
1,6-Hexanediamine (HDA) is a high production volume chemical which is used as an intermediate in the synthesis of paints, resins, inks, and textiles and as a corrosion inhibitor in lubricants. Two- and 13-week studies of the toxicity of the dihydrochloride salt of HDA (HDDC) were conducted in male and female Fischer 344/N rats and B6C3F1 mice using whole-body inhalation exposure. Both species were evaluated for histopathologic and reproductive effects, and rats were examined for clinical chemistry and hematologic changes. In the 2-week inhalation studies, animals were exposed to 10-800 mg HDDC/m3, 6 hr per day. All rats, all female mice, and two of five male mice in the high-exposure group died before the end of the study. Surviving mice in this group had a dose-dependent depression in body weight gain. Clinical signs were primarily related to upper respiratory tract irritation and included dyspnea and nasal discharge in both species. Treatment-related histopathologic lesions included inflammation and necrosis of the laryngeal epithelium of both species and the tracheal epithelium of mice, as well as focal inflammation and ulceration of the respiratory and olfactory nasal mucosa. In the 13-week inhalation studies, animals were exposed to HDDC at concentrations of 1.6-160 mg/m3 for 6 hr per day, 5 days per week. In addition to the base study groups, a supplemental group of rats at each exposure level was included to assess the effect of HDDC on reproduction. No treatment-related changes in organ weights or organ-to-body-weight ratios occurred in rats, and no treatment-related clinical signs or gross lesions were seen in either species. Chemical-related microscopic lesions were limited to the upper respiratory tract (larynx and nasal passages) in the two highest exposure groups and were similar in both species. These lesions included minimal to mild focal erosion, ulceration, inflammation, and hyperplasia of the laryngeal epithelium, in addition to degeneration of the olfactory and respiratory nasal epithelium. HDDC caused no significant changes in sperm morphology or vaginal cytology and no significant adverse effects on reproduction in rats or mice. Hematologic and clinical chemistry changes in rats were minor and sporadic and were not accompanied by related histologic findings. HDDC did not increase the frequency of micronucleated erythrocytes in mice.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献