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31.
在高水头水电站明岔管设计中 ,由于岔管的钢管壁较厚 ,给岔管的制作带来很大的困难。为此在大七孔电站钢岔管设计时 ,借鉴国内的钢衬钢筋混凝土管技术的经验 ,采用了钢衬钢筋混凝土岔管。解决了高水头岔管的设计及施工难题 相似文献
32.
We use retrodictive quantum theory to describe cavity field measurements by successive atomic detections in the micromaser. We calculate the state of the micromaser cavity field prior to detection of sequences of atoms in either the excited or ground state, for atoms that are initially prepared in the excited state. This provides the POM elements, which describe such sequences of measurements. 相似文献
33.
Nearly all seal rotordynamics models were forced to assume that the seal-inlet swirl velocity disturbance boundary condition components (W 1C and W 1S ) are zero. The companion (Part 1) paper employs an extensive parametric study to develop a complete set of widely applicable seal-inlet disturbance boundary condition correlations that will alleviate this shortcoming. The benefits of using the new seal-inlet boundary condition correlations were assessed by implementing them into a CFD-perturbation model. Two widely different test cases were employed. Case 1 is a test of the correlations for large upstream chambers using a simple liquid smooth-plain seal, and Case 2 is a test for small, as well as radial injection, upstream chambers using a complicated gas labyrinth seal. For both cases, consistently improved agreement with measurements was obtained for the options with non-zero W 1C and W 1S compared to the option with W 1C = W 1S = 0. Specifically, the correlation set using the W 1C -profile option gave a clearly better prediction of the effective damping and the cross-coupled stiffness than did the set using the W 1C -bulk option for the higher spin speed case of the challenging gas labyrinth. For the smooth-plain liquid seal case, the correlations with the W 1C -profile and W 1C -bulk options gave nearly the same level of agreement with measurements. 相似文献
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36.
The effects of 0, 1.0, 2.0 and 4.0 (x 10?3 M) α-, γ- or δ-tocopherol on chlorophyll b photosensitized oxidation of soybean oil in methylene chloride were studied by peroxide values and headspace oxygen. As concentrations of tocopherols increased, peroxide values decreased and headspace oxygen increased (P < 0.05). At 1.0 × 10?3 M, α-tocopherol showed highest antioxidant effect, γ-tocopherol second and then δ-tocopherol. α- and -γ-Tocopherols had similar effects and δ-tocopherol had lower effect at 2.0 × 10?3 M (P < 0.05). However, the three tocopherols were not different (P > 0.05) at 4.0 × 10?3 M. α-Tocopherol quenched singlet oxygen to reduce the photosensitized oxidation of oil. The quenching rate constants of α-tocopherol were 2.7 × 107M?1sec?1 by peroxide value and 2.6 × 107 M?1sec?1 by headspace oxygen. 相似文献
37.
Effect of Blanching and Drying on Pectin Constitutents and Related Characteristics of Dehydrated Peaches 总被引:1,自引:0,他引:1
The effects of sulfuring, blanching, dehydration, and storage (of dehydrated fruits), on the pectic constitutents and other characteristics of peaches are reported. Adequate blanching stabilized pectins of the dehydrated peaches so higher rehydration capacity and lower rehydration losses were observed after 5 min blanching. Increase in degradation was observed in nonblanched or 1.5 min heat-treated fruits, which resulted in lower rehydration capacity. A significant correlation was found between the contents of total pectin and protopectin fractions and the firmness or rehydration ratio of the peaches. Thus, pectin, one of the major cell-wall and intercellular tissue components, plays a significant role in determining the textural-structural characteristics of dehydrated fruits. 相似文献
38.
The clinical course was studied as was the condition of cardiohemodynamics in 126 patients with different variants of diphtherial myocarditis (DM) versus 23 patients with unspecific infectious and allergic myocarditis (UIAM). Early DM in the majority of cases runs a moderately severe or severe course because of a stronger--by comparison with late DM and UIAM--predisposition to cardiac insufficiency, sinus bradycardia and heart blocks as well as of a moderately severe systolic dysfunction of the left ventricle (LV), as evidenced by Echo-CG. Late DM runs, on the whole, a mild course, and is associated with minimal LV systolic function inadequacies. 相似文献
39.
P Brenneisen J Wenk LO Klotz M Wlaschek K Briviba T Krieg H Sies K Scharffetter-Kochanek 《Canadian Metallurgical Quarterly》1998,273(9):5279-5287
40.
LO Hattenbach G Steinkamp I Scharrer C Ohrloff 《Canadian Metallurgical Quarterly》1998,212(6):394-398
In a retrospective study the outcome of patients treated by the Kapandji-Sauvé procedure was evaluated. In the period from 1989 to 1993, 18 patients were operated. The arthrodesis of the distal radioulnar joint was performed by a dorsoulnar incision using one screw. A 2 cm long segment of the ulna was resected. Indications for Kapandji-Sauvé procedures were in 12 cases deformities subsequent to wrist fractures, in three cases osteoarthrosis of the distal radioulnar joint, in two cases Madelung's deformity and in one case Kienb?ck's disease. The mean follow-up time was 5.1 years (range 3 to 7 years). There was one case of reossification, which required reoperation. No other complications were seen. An excellent result was obtained in seven patients, a good result in nine patients, one patient showed satisfactory and one poor results. Grip strength was normal in six cases, reduced up to 20% in seven cases and reduced up to 50% in five cases. 13 patients returned to their previous occupation. 12 patients showed a range of pronation-supination of more than 150 degrees. There was no correlation between X-ray findings and clinical outcome in patients. 相似文献