Influence of a Spacer in Open Part of Horn Model on Acoustic Characteristic

2018 ◽  
Vol 2018.93 (0) ◽  
pp. P057
Author(s):  
Yuri TANIGUCHI ◽  
Yohsuke TANAKA ◽  
Shigeru MURATA
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Gui-yang Xu ◽  
Chun-guang Wang ◽  
Yan-fang Zhu ◽  
Hong-yan Li ◽  
Lun-kun Gong ◽  
...  

AbstractThe experiment system of pulse detonation engine is set up to investigate on influence of diameter on detonation acoustic characteristic. The research of detonation acoustic characteristic of pulse detonation engine for four different diameters in different angles is carried out. Results from the test show that as the PDE diameter increasing, there are increases in amplitudes of impact noise in all angles, and the growth rate of amplitude of impact noise in the 90° direction is generally greater than that in the 0° direction. The smaller PDE diameter is, the distance of most obvious directivity at 0° turning to most obvious directivity at 30° is shorter. When the distance is shorter, such as 200 mm, the duration of detonation acoustic is increasing with the increase of PDE diameter, however, when the distance is longer, such as 3000 mm, it is just the opposite. The maximum duration of detonation acoustic is appeared in 3000 mm under 30 mm PDE diameter which reaches to 1.44 ms.


2019 ◽  
Vol 488 (3) ◽  
pp. 294-297
Author(s):  
V. N. Smirnov ◽  
K. S. Ivanov

40Ar/39Ar-dating of the micas from the schists and blastomylonites collected from the fault which separates the Eastern zone of the Middle Urals dipped under the cover of the West Siberian plate from the open part of the geologic structures of the Urals, showed that the last phase of deformation was represented by a submeridional sinistral strike-slip faults with the age of 251 Ma. The appearance of the analyzed deformations practically exactly coincides in time with the formation of the grabens of meridional strike at the base of the West Siberian plate. 


Author(s):  
Aleksandr Kitov ◽  
Ivan Denisenko ◽  
Oxana Lunina ◽  
Andrey Gladkov ◽  
Viktor Plyusnin ◽  
...  

The Munku-Sardyk (Eastern Sayan) glacier has been described and studied for more than 100 years. The first largest glacier of Peretolchina was studied in the most detailed detail. Radde's second-largest glacier is much weaker. Monitoring of surface characteristics of the Radde glacier by ground methods and using data of remote sensing of the Earth (RSE) has been carried out since 2006. In 2018, georadar profiling of this glacier was performed for the first time. As a result, it was possible not only to clarify its surface characteristics, but also to assess the power of the ice and the internal structure (a layer of firn, ice, bed). According to the RSE, its geometric changes have been revealed. Over 120 years, the open part of the Radde Glacier has shrunk from 0.4 to 0.09 km2, and the length from 1 to 0.4 km. It also revealed the division of the glacier into two parts and the intensive reservation of the bottom of the main part of the tongue by surface moraines and the formation of a glacial lake on the glacier itself in the lower part of the second half. Radar research using the Oko-2 georadar, allowed to determine the volume of ice of this glacier 0.003 km3 and the greatest thickness of the main ice body 42 m. The main glacier flows down from the Eskadriliy top, 3168 m, to the north, flows on the cross-bar and from it turns to the northeast, and at the bottom of the kar will continue to flow north again.


2021 ◽  
Vol 149 (4) ◽  
pp. A127-A127
Author(s):  
Hung T. Doan ◽  
Christopher Hakoda ◽  
John Greenhall ◽  
Cristian Pantea ◽  
Troy Semelsberger

1786 ◽  
Vol 76 ◽  
pp. 236-240
Keyword(s):  

The severe frost of December, 1784, broke early in January, and was all gone before the middle, and the most open part of this sharp winter followed it, being misty or thick and warm very wet air; but the last day of January another frost set in, which, though not so steady as the former, was sometimes very severe, and did not go away till near the middle of March.


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