scholarly journals Determination of the height of Mount Everest using the shallow layer method

2021 ◽  
Author(s):  
Youchao Xie ◽  
Wenbin Shen ◽  
Jiancheng Han ◽  
Xiaole Deng
Keyword(s):  
Mount Everest ◽  
Layer Method ◽  
Shallow Layer

Determining the height of Mount Everest using the shallow layer method

2021 ◽  
Author(s):  
Youchao Xie ◽  
Wenbin Shen ◽  
Jiancheng Han ◽  
Xiaole Deng
Keyword(s):  
Gravity Field ◽  
Field Model ◽  
Space Station ◽  
Geoid Undulation ◽  
Mount Everest ◽  
Gravity Field Model ◽  
Terrain Model ◽  
Earth Gravity ◽  
Layer Method ◽  
Shallow Layer

<p>We proposed an alternative method to determine the height of Mount Everest (HME) based on the shallow layer method (SLM), which was put forward by Shen (2006). We use the precise external global Earth gravity field model (i.e., EGM2008 and EIGEN-6C4 models) as input information, and the digital topographic model (i.e., DTM2006.0) and crust models (i.e., CRUST2.0 and CRUST1.0 models) to construct the shallow layer model. There are four combined strategies：(1) EGM2008 and CRUST1.0 models, (2) EGM2008 and CRUST2.0 models, (3) EIGEN-6C4 and CRUST1.0 models, and (4) EIGEN-6C4 and CRUST2.0 models, respectively. We calculate the HME by two approaches: first approach, the HME is directly calculated by combining the geoid undulation (N) and geodetic height (h); second approach, we calculate the HME by the segment summation approach (SSA) using the gravity field inside the shallow layer determined by the SLM. Numerical results show that for four combined strategies, the differences between our results and the authoritatively released value 8848.86 m by the Chinese and Nepalese governments on December 8, 2020 are 0.448 m, -0.009 m, -0.295 m, and -0.741 m using first approach and 0.539 m, 0.083 m, -0.214 m, and -0.647 m using second approach. The combined calculation of the HME by the terrain model and gravity field model is more accurate than that by the gravity field model alone. This study is supported by the National Natural Science Foundations of China (NSFC) under Grants 42030105, 41721003, 41804012, 41631072, 41874023, Space Station Project (2020)228.</p>

A Novel Amperometric Immunosensor Based on Thionine/DNA Self-Assembled Multilayers on Carbon Nanotubes Modified Glass Carbon Electrode

2010 ◽  
Vol 160-162 ◽  
pp. 1170-1175 ◽  
Author(s):  
Li Yong Jia ◽  
Ning Gan ◽  
Lei Zheng ◽  
Qian Wang
Keyword(s):  
Carbon Nanotubes ◽  
Layer By Layer ◽  
Amperometric Immunosensor ◽  
Multi Wall Carbon Nanotubes ◽  
Glass Carbon Electrode ◽  
Layer Method ◽  
Glass Carbon ◽  
Positively Charged ◽  
Dna Film

A novel amperometric immunosensor for the determination of alpha-fetoprotein (AFP) was constructed using multi-wall carbon nanotubes modified glass carbon electrode.thionine as the mediator,were immobilized by DNA throngh the layer-by-layer method. Thionine was first fabricated on carbon nanotubes modified glass carbon throngh 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide(EDC/NHS).then a negatively charged DNA film was absorbed on the positively charged thionine,and the DNA was uesd as cross-linker to immobiled amount thionine.nano-Au-was used to immobilized anti-AFP.The electrochemical sensor have a relatively low detection limit of 0.02ng/ml.

On convection under an air surface

1967 ◽  
Vol 30 (1) ◽  
pp. 9-15 ◽  
Author(s):  
E. L. Koschmieder
Keyword(s):  
Constant Temperature ◽  
Silicone Oil ◽  
Fluid Layer ◽  
Accurate Determination ◽  
Glass Plate ◽  
Copper Plate ◽  
Hexagonal Pattern ◽  
Shallow Layer

A shallow layer of silicone oil on a plane, circular copper plate was uniformly heated from below. The air on its surface was kept at constant temperature by a uniformly cooled glass plate close to the oil, which at the same time inhibited air motions. Motions began with concentric circular rolls which, after the centre ring had formed, broke down into a hexagonal pattern. A rather accurate determination of the wavelength of the motions was possible. The wavelength was found to be variable with the depth of the fluid layer in qualitative accordance with the theory of Nield. Supercritical motions are briefly discussed.

The Highest Fossils in the World

1967 ◽  
Vol 104 (1) ◽  
pp. 73-74 ◽  
Author(s):  
N. E. Odell
Keyword(s):  
Age Determination ◽  
Upper Permian ◽  
Lower Permian ◽  
Mount Everest ◽  
Fine Grained ◽  
The World ◽  
Rock Specimens ◽  
Stem Fragment ◽  
Crystalline Matrix

In his splendid volume Geology of the Himalayas (1964; reviewed in this Number, p. 86), Professor Augusto Gansser refers (p. 164) to the rock specimens brought back from the summit of Mount Everest by the successful Swiss climbers in 1956, and also by the American team in 1963. All the various summit specimens, Professor Gansser states, are lithologically quite identical. They consist of fine-grained, thin-bedded grey calc-schists or platy limestones. The calcites are elongated conformably with the schistosity, which seems to parallel the bedding. The detrital grains are mostly quartz, acid plagioclases and some microline, together with fine sericite lamellae, paralleling the calcites. Gansser continues: “Of special interest is the fact that both samples contain crinoidal fragments. Their large uniform calcite crystals contrast with the otherwise much finer crystalline matrix. In one elongated stem-fragment the segmentation is visible (Photo. 46), while one small plate still shows the well-preserved perforation (Photo. 47).” Moreover, he observes: “These remnants, representing the highest fossils in the world, are unfortunately not sufficiently well-preserved to allow an age-determination of the top Everest limestone. They do, however, support rather than contradict the Carboniferous (to Lower Permian) age generally assigned to the Everest limestones, on the grounds that they are overlain by the (Upper) Permian Lachi Series (Odell, 1943; Wager, 1939).”

THE DETERMINATION OF MOISTURE IN HONEY BY THE HYDROMETER METHOD

1933 ◽  
Vol 8 (5) ◽  
pp. 435-439 ◽  
Author(s):  
H. D. Chataway
Keyword(s):  
Water Layer ◽  
Shallow Layer

The hydrometer method of testing honeys has been shown to give results as satisfactory as those obtained by other methods provided that; (1) a large sensitive hydrometer is used, (2) the percentage of moisture is calculated from a proper honey table and not from the usual sugar tables, and (3) a shallow layer of water is added to the surface of the honey after the hydrometer has been introduced. A suitable, specially constructed hydrometer is described, and a table of true honey densities has been drawn up. For accurate work the observed densities should be corrected for the slight error which would otherwise arise from the smaller buoyancy thrust of the water layer as compared with a honey layer of the same thickness.

XRF Analysis of Microsamples of Semiconductor Type Multielement Materials by the Thin Layer Method. Determination of Cr, Co, Ni, Cu, Zn, Ga, Se, Sb, Yb

1999 ◽  
Vol 132 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Jerzy Jurczyk ◽  
Rafał Sitko ◽  
Beata Zawisza ◽  
Franciszek Buhl ◽  
Ewa Malicka
Keyword(s):  
Thin Layer ◽  
Xrf Analysis ◽  
Layer Method ◽  
Thin Layer Method ◽  
Semiconductor Type

An alternative geoid model for Africa using the shallow-layer method

2021 ◽  
Author(s):  
Mostafa Ashry ◽  
Wen-Bin Shen ◽  
Hussein A. Abd-Elmotaal
Keyword(s):  
Geoid Model ◽  
Layer Method ◽  
Shallow Layer

scholarly journals The geoid of China and its surrounding areas determined by shallow layer method

2021 ◽  
Vol 32 (5.2) ◽  
Author(s):  
Youchao Xie ◽  
Wen-Bin Shen ◽  
Jiancheng Han ◽  
Jiancheng Li
Keyword(s):  
Layer Method ◽  
Shallow Layer ◽  
Surrounding Areas

Development of a global geoid model 2020 (GGM2020)

2020 ◽  
Author(s):  
WenBin Shen ◽  
Youchao Xie ◽  
Jiancheng Han ◽  
Jiancheng Li
Keyword(s):  
Gravity Field ◽  
Density Model ◽  
Layer Model ◽  
Geoid Model ◽  
Gravity Field Model ◽  
Layer Method ◽  
Shallow Layer ◽  
Inner Surface ◽  
Gps Leveling ◽  
Better Than

<p>We present an updated 5′ ×5′ global geoid model 2020 (GGM2020), which is determined based on the shallow layer method (or simply Shen method). We choose an inner surface S below the EGM2008 global geoid by 15 m, and the layer bounded by the inner surface S and the Earths geographical surface E is referred to as the shallow layer. We formulate the 3D shallow mass layer model using the refined 5′ ×5′ crust density model, CRUST1.0-5min, which is an improved 5′ ×5′ density model of the CRUST1.0 with taking into account the corrections of the areas covered by ice sheets and the land-ocean crossing regions. Based on the shallow mass layer model and the gravity field EGM2008 that is defined in the region outside the Earth’s geographical surface E, we determine the gravity field model EGM2008S that is defined in the whole region outside the inner surface S. Based on the gravity field EGM2008S and the geoid equation W(P) =W0, where W0 is the geopotential constant on the geoid and P is the point on the geoid G, we established a 5′ ×5′ global geoid model GGM2020. Comparisons show that in average the GGM2020 fits the globally available GPS/leveling points better than the EGM2008 global geoid. This study is supported by NSFCs (grant Nos. 41721003, 41631072, 41874023, 41804012, 41429401, 41574007).</p>

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