Supplementary material to "Technical Note: Real-Time Diagnosis of the Hygroscopic Growth Micro-Dynamics of Nanoparticles with Two-Dimensional Correlation Infrared Spectroscopy"

Abstract. Nanoparticles can absorb water to grow up and this will affect the light scattering behavior, cloud condensation nuclei properties, lifetime, and chemical reactivity of these particles. Current techniques usually assume the shapes of nanoparticles to be spherical in calculation of aerosol liquid water content (ALWC), which may result in large uncertainties when the shapes of nanoparticles show large deviations to the spherical assumptions. Furthermore, current techniques are also difficult to identify the intermolecular chemical interactions of phase transition micro-dynamics during nanoparticle deliquescence process because their limited temporal resolutions are unable to capture the complex femtosecond-level intermediate states. In this study, the hygroscopic growth properties of nanoparticles with electrical mobility diameter of approximately 100 nm and their phase transition interaction dynamics on molecular scale are characterized on real time by using the Fourier transform infrared (FTIR) and the two-dimensional correlation infrared (2D-IR) spectroscopic techniques. With the FTIR spectroscopy, we develop a novel real-time method for ALWC by constructing the absorption spectra of liquid water, and realized real-time measurements of water content and dry nanoparticle mass to characterize the hygroscopic growth factors (GF) which show discrepancies to the extended aerosol inorganics model (E-AIM). We further explore the difference that the deliquescence points of sodium nitrate (SN) and oxalic acid (OA) compounds are lower than that of AS by using the 2D-IR spectroscopic analysis technique. We also identify the occurrence sequential order of the hydration interactions and investigate the dynamic deliquescence process of the functional groups for AS and its mixture compounds. Both SN and OA compounds lower the deliquescence point of AS, but only AN can change the hydrolysis reaction mechanism for AS in AS/AN and AS/OA mixtures. This study can not only provide important information with respect to the difference in phase transition point under different conditions, but also improve current understanding of the chemical interaction mechanism between nanoparticles (particularly for organic particles) and medium, which is of great significance for haze control across China.

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CALCULATION OF THE DEPENDENCE OF THE DISTANCE TO THE LOCATED OBJECT FROM THE CORNER POSITION OF THE VEHICLE LINE

Issues of radio electronics ◽

10.21778/2218-5453-2018-4-14-18 ◽

2018 ◽

pp. 14-18

Author(s):

V. V. Artyushenko ◽

A. V. Nikulin

Keyword(s):

Real Time ◽

Statistical Physics ◽

Angular Position ◽

Three Dimensional ◽

Line Of Sight ◽

Two Dimensional ◽

Radar Station ◽

Flight Mode ◽

Vector Algebra ◽

Analytical Expressions

To simulate echoes from the earth’s surface in the low flight mode, it is necessary to reproduce reliably the delayed reflected sounding signal of the radar in real time. For this, it is necessary to be able to calculate accurately and quickly the dependence of the distance to the object being measured from the angular position of the line of sight of the radar station. Obviously, the simplest expressions for calculating the range can be obtained for a segment or a plane. In the text of the article, analytical expressions for the calculation of range for two-dimensional and three-dimensional cases are obtained. Methods of statistical physics, vector algebra, and the theory of the radar of extended objects were used. Since the calculation of the dependence of the range of the object to the target from the angular position of the line of sight is carried out on the analytical expressions found in the paper, the result obtained is accurate, and due to the relative simplicity of the expressions obtained, the calculation does not require much time.

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Accelerating laser processes with a smart two-dimensional polygon mirror scanner for ultra-fast beam deflection

Advanced Optical Technologies ◽

10.1515/aot-2021-0014 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Florian Roessler ◽

André Streek

Keyword(s):

Energy Distribution ◽

Real Time ◽

Laser Processing ◽

High Speed ◽

Beam Deflection ◽

Two Dimensional ◽

Heat Accumulation ◽

Field Programmable ◽

Drill Holes ◽

Average Laser

Abstract In laser processing, the possible throughput is directly scaling with the available average laser power. To avoid unwanted thermal damage due to high pulse energy or heat accumulation during MHz-repetition rates, energy distribution over the workpiece is required. Polygon mirror scanners enable high deflection speeds and thus, a proper energy distribution within a short processing time. The requirements of laser micro processing with up to 10 kW average laser powers and high scan speeds up to 1000 m/s result in a 30 mm aperture two-dimensional polygon mirror scanner with a patented low-distortion mirror configuration. In combination with a field programmable gate array-based real-time logic, position-true high-accuracy laser switching is enabled for 2D, 2.5D, or 3D laser processing capable to drill holes in multi-pass ablation or engraving. A special developed real-time shifter module within the high-speed logic allows, in combination with external axis, the material processing on the fly and hence, processing of workpieces much larger than the scan field.

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