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101.
瞬时吸收率检测与高频噪声的剔除 总被引:4,自引:4,他引:0
在高分辨率处理过程中,由于地震数据记录中存在着一类并不被人们十分注意的,但影响却十分严重的高频噪声,使得高分辨率处理结果陷入一种“混沌”状态。为此,本文仔细分析和研究了这类噪声产生的物理机制和原因,并提出瞬时吸收率检测与高频噪声剔除的方法。 相似文献
102.
In this paper, dynamic model of a class of parallel systems, namely, the hexaslides, is proposed. The model developed is based on the concept the decoupled natural orthogonal complement (DeNOC) matrices, introduced elsewhere. The dynamic model of hexslides, though complex due to the existence of multi-loop kinematic chains, is required for actuator power estimation, computed-torque control, optimum tool trajectory generation, etc. The use of DeNOC offers many physical interpretations, recursive algorithms, and parallel computations. Using the proposed dynamic model, a parallel inverse dynamics algorithm has been presented to compute the actuator forces. This is useful to choose suitable motors for an application. An illustration is provided using an existing machine tool based on hexaslides, namely, the HexaM, while it is carrying out a circular contouring. Secondly, the effect of leg and slider inertias is also studied, which clearly suggests that neither of these can be neglected while finding the actuator forces. 相似文献
103.
U V Varadaraju G V Subba Rao K D Chandrasekaran A Baradarajan K Krishnaiah Mukesh Agarwala V S Achutharaman P Venugopal K A Padmanabhan L S Vaidyanathan G Rangarajan 《Bulletin of Materials Science》1989,12(1):63-80
The oxygen-deficient phase of the highT
c superconductor, YBa2Cu3O7, was oxygen-enriched using the fluidization technique to give good superconducting properties. The normal method of oxygen
treatment at 900°C for 24 h and at 600°C for 24 h has been reduced to just one treatment at 600°C for 12 h by the fluidization
technique to achieve almost the same strength of superconducting signal for the YBa2Cu3O7 powder, which establishes the attractiveness of the latter route for the large-scale preparation of superconducting material.
The particle sizes were in the range 0–90, 90–180 and 180–420 μm. The fluidized particles were crystalline with orthorhombic
distortion.T
c
onset
, estimated using the a.c. magnetic susceptibility method, was 91·3 K. The volume fraction of superconducting material in
the product was 83·7–85·3%, one of the highest values reported so far for YBa2Cu3O7. 相似文献
104.
105.
通过对膨胀土特性和膨胀土对建筑物造成危害的了解,分析了影响膨胀土胀、缩变形的主要内在因素和外部因素,提出了电力变电站膨胀土地基施工的预防控制措施。 相似文献
106.
New spectrophotometric methods for the assay of some antioxidants have been developed using potassium permanganate and metol (p-N-methyl amino phenol). Metol is oxidised at pH 3.0 with potassium permanganate and coupled with antioxidants to give λmax at 560 nm for propyl gallate and gallic acid and 510nm for butylated hydroxy anisole. The method is simple, sensitive, reproducible and accurate within ±1% and applicable to the assay of antioxidants (gallic acid, propyl gallate and butylated hydroxy anisole) in oils and fats. 相似文献
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110.
Hari B. Goyal M. O. Garg K. R. Rao R. D. Srivastava 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(2):49-56
The kinetics of the reaction of acetic acid and acetylene over zinc acetate-activated carbon catalyst was investigated over a wide range of process variables in a pilot reactor. Although various catalytic reaction mechanisms were postulated, the rate of reaction was most satisfactorily correlated by a mechanism of surface reaction between charged adsorbed acetic acid and acetylene, which assumes that the rate controlling step was the irreversible charged adsorption of acetylene and acetic acid. 相似文献