scholarly journals ESTIMATION OF PARTICLE SIZE INFORMATION OF SURFACE SEDIMENTS BY ULTRASONIC PULSE WAVES

2017 ◽  
Vol 73 (2) ◽  
pp. I_1633-I_1638
Author(s):  
Yuki IIYOSHI ◽  
Shigeru KATO ◽  
Naohiro HOZUMI ◽  
Takumi OKABE
2014 ◽  
Vol 70 (2) ◽  
pp. I_1476-I_1480
Author(s):  
Ryota NAKAJIMA ◽  
Shigeru KATO ◽  
Naohiro HOZUMI ◽  
Takumi OKABE

2020 ◽  
Author(s):  
Lihui Tian ◽  
Dengshan Zhang ◽  
Yang Yu

<p>Soil particles are related to vegetation growth and source of depositsc in arid and semi-arid desert. It is worth mentioning that plantation is the one the most effective ways improving desert soil conditions. The sandy land on the eastern shore of Qinghai Lake is the biggest area in the desertified land of Qinghai Lake Basin. Some measures have been taken to prevent and control desertification in Kutu district since 2008. We chose the dunes that planted Salix cheilophila、Hippophae rhamnoides、Pinus sylvestris、Populus simonii and Hedysarum scoparium as study sites, then collected deposits from topsoil to the depth of 60 cm to probe into the change of grain size features. The results show that: (1) All study dunes primarily are made up of medium materials for mean particle size (M) is medium sand widely distributed from 0.27mm to 0.31mm which are presented uniform. (2) The sorting coefficient of sediments is concentrated between 0.5 and 0.9 with better performance. The skewness value is between 0 and 1, which shows nearly symmetrical and positive skewness. The kurtosis is between wide and medium. (3) The vertical change of particle size composition at different depths of 60 cm indicates that plantation significantly changed the distribution of the surface sediments in the dunes, whereas particle compositions at different depths did not have obvious rules of different plants. (4) The vegetation recovery time in study area was short, therefore, interactions between wind sorting, terrain fluctuations and vegetation growth might affect the grain size features of surface sediments in study area.</p>


2013 ◽  
Vol 6 (3) ◽  
pp. 5065-5099
Author(s):  
L. A. Rieger ◽  
A. E. Bourassa ◽  
D. A. Degenstein

Abstract. The Optical Spectrograph and InfraRed Imaging System (OSIRIS) on-board the Odin satellite has now taken over a decade of limb scatter measurements that have been used to retrieve the Version 5 stratospheric aerosol extinction product. This product is retrieved using a representative particle size distribution to calculate scattering cross sections and scattering phase functions for the forward model calculations. In this work the information content of OSIRIS measurements with respect to stratospheric aerosol is systematically examined for the purpose of retrieving particle size information along with the extinction coefficient. The benefit of using measurements at different wavelengths and scattering angles in the retrieval is studied and it is found that incorporation of the 1530 nm radiance measurement is key for a robust retrieval of particle size information. It is also found that using OSIRIS measurements at different solar geometries simultaneously provides little additional benefit. Based on these results, an improved aerosol retrieval algorithm is developed that couples the retrieval of aerosol extinction and mode radius of a log-normal particle size distribution. Comparison of these results with coincident measurements from SAGE III show agreement in retrieved extinction to within approximately 10% over the bulk of the aerosol layer, which is comparable to Version 5. The retrieved particle size, when converted to Ångström coefficient, shows good qualitative agreement with SAGE II measurements made at somewhat shorter wavelengths.


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