System research of thermal physics boundary problems and the determination of high accuracy temperature fields in a variety of Riemann spaces

We show that the degree of oxidation of graphene oxide (GO) can be obtained by using a combination of state-of-the-art ab initio computational modeling and X-ray photoemission spectroscopy (XPS). We show that the shift of the XPS C1s peak relative to pristine graphene, ΔEC1s, can be described with high accuracy by ΔEC1s=A(cO−cl)2+E0, where c0 is the oxygen concentration, A=52.3 eV, cl=0.122, and E0=1.22 eV. Our results demonstrate a precise determination of the oxygen content of GO samples.

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Electrochemical device based on nonspecific DNAzyme for the high-accuracy determination of Ca2+ with Pb2+ interference

Bioelectrochemistry ◽

10.1016/j.bioelechem.2020.107732 ◽

2020 ◽

pp. 107732

Author(s):

Hui Wang ◽

Qingyao Luo ◽

Yiguang Zhao ◽

Xuemei Nan ◽

Fan Zhang ◽

...

Keyword(s):

High Accuracy ◽

Electrochemical Device ◽

Accuracy Determination

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Based on Atomic Spectrometry for the Determination of Titanium Element in Molten Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1528 ◽

2012 ◽

Vol 622-623 ◽

pp. 1528-1531

Author(s):

Cui Hong Ma ◽

Wei Qiang Zhang

Keyword(s):

Molten Steel ◽

Emission Spectroscopy ◽

Atomic Emission ◽

Lag Time ◽

High Accuracy ◽

Atomic Spectrometry ◽

Atomic Emission Spectrometry ◽

Emission Spectrometry ◽

Important Significance

Atomic emission spectrometry with high accuracy, short lag time, and low detection limit, it has been widely applied in various fields. The application of atomic emission spectrometry in the converter steelmaking process has an important significance to improve the smelting of speed and steel quality. This article describes the principle of atomic emission spectroscopy (AES) analysis. Spectra obtained by the experimental for qualitative analysis, detected molten steel containing titanium element.

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High accuracy determination of the thermal properties of supported 2D materials

Scientific Reports ◽

10.1038/srep12422 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 47

Author(s):

Jarosław Judek ◽

Arkadiusz P. Gertych ◽

Michał Świniarski ◽

Anna Łapińska ◽

Anna Dużyńska ◽

...

Keyword(s):

Thermal Properties ◽

2D Materials ◽

High Accuracy ◽

Accuracy Determination

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DIGITAL ZENITH CAMERA FOR VERTICAL DEFLECTION DETERMINATION

Geodesy and Cartography ◽

10.3846/20296991.2012.755324 ◽

2012 ◽

Vol 38 (4) ◽

pp. 123-129 ◽

Cited By ~ 19

Author(s):

Māris Abele ◽

Jānis Balodis ◽

Inese Janpaule ◽

Ieva Lasmane ◽

Augusts Rubans ◽

...

Keyword(s):

Data Processing ◽

Digital Imaging ◽

High Accuracy ◽

Reference Star ◽

Research Groups ◽

Vertical Deflection ◽

Digital Imaging Technology ◽

Prototype Instrument ◽

Automated Determination

Recent accomplishments in advancement of accurate astrometric reference star catalogues, development of digital imaging technology, high accuracy tiltmeter technology, and geocentric coordinate availability provided by GNSS, have made possible accurate, fast and automated determination of vertical deflections using astrometric methods. Zenith cameras for this kind of measurements have been developed or are being developed by several research groups. The paper describes a research project by Institute of Geodesy and Geoinformation, intended to design a portable digital zenith camera for vertical deflection determination with 0.1” expected accuracy. Camera components are described, proposed data processing algorithm and preliminary results, obtained with prototype instrument, are presented.

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Technique and results of experimental determination of the compressibility factor of the natural gas

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2021-9-35-40 ◽

2021 ◽

pp. 35-40

Author(s):

Denis Y. Kutovoy ◽

Igor A. Yatsenko ◽

Vladimir B. Yavkin ◽

Aydar N. Mukhametov ◽

Petr V. Lovtsov ◽

...

Keyword(s):

Natural Gas ◽

Equations Of State ◽

Compressibility Factor ◽

High Accuracy ◽

State Equations ◽

Actual Problem ◽

Temperature Range ◽

Relative Value ◽

Compressibility Coefficient

The actual problem of the possibility of using the equations of state for the gas phase of natural gas at temperatures below 250 K is considered. To solve it, the compressibility coefficients of natural gas obtained experimentally with high accuracy are required. The technique was developed and experimental study was carried out of compressibility factor aiming expanding temperature range of the state equations GERG-2004 and AGA8-DC92. The proposed technique is based on the fact that to assess the applicability of the equation of state, it is sufficient to obtain the relative value of the compressibility coefficient and not to determine its absolute value. The technique does not require complex equipment and provides high accuracy. The technique was tested on nitrogen, argon, air and methane. Uncertainty of determination of the compressibility factor is not greater than 0.1 %. For two different compositions of natural gas, obtained experimental data were demonstrated that the equations of state GERG-2004 and AGA8-92DC provide uncertainty of the calculation of the compressibility coefficient within 0.1 % in the temperature range from 220 K to 250 K and pressure below 5 MPa.

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INCREASING THE RESOURCE OF DIESEL CYLINDER HEADS BY IMPROVING THE TECHNOLOGY OF THEIR RESTORATION

SCIENTIFIC LIFE ◽

10.35679/1991-9476-2020-15-7-950-957 ◽

2020 ◽

Vol 15 (7) ◽

pp. 950-957

Author(s):

G.D. Mezhetskiy ◽

◽

V.A. Strelnikov ◽

Keyword(s):

Diesel Engines ◽

Thermal Loading ◽

Theoretical Calculations ◽

Operating Conditions ◽

Advanced Technology ◽

Temperature Fields ◽

Cylinder Block ◽

Diesel Cylinder ◽

Thermal Intensity

The article presents the results of studies of the thermal fatigue strength of diesel cylinder heads and their resource under operating conditions, by using the most advanced technology for their restoration. Based on the results of theoretical calculations of durability and operational studies, a restoration technology has been proposed, which makes it possible to increase the resource of cylinder heads by 2 ÷ 2.5 times. For this purpose, the non-uniformity of the temperature field on the firing bottom of the cylinder heads of YaMZ-238NB diesel engines was theoretically determined and experimentally confirmed. On the basis of theoretical calculations, the most heatstressed sections of the plane of the cylinder heads of diesel engines bonded to the cylinder block were determined, and the appearance of cracks in them. When developing a method for calculating the temperature fields of the fire bottom, the universal finite element method (FEM) was used. This method makes it possible to take into account the geometry and conditions of thermal loading of the cylinder heads quite accurately. For the determination of temperature fields, a well-founded assignment of the boundary conditions is crucial. With this in mind, a number of surfaces were determined that characterize the durability of the entire part during operation. As a result of calculations carried out on a computer, temperature fields have been obtained that make it possible to analyze the distribution of temperatures and temperature gradients at any point of the fire bottom. The highest temperatures (620...635K) are localized in the central part of the fire bottom, which is two times higher in thermal intensity than the peripheral one and confirms the appearance of cracks in these places during the operation of diesel cylinder heads.

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