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Статті в журналах з теми "Vapor plume"

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Автор: Grafiati

Опубліковано: 7 липня 2024

Оновлено: 7 липня 2024

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1

Zhu, Xiaojing, Weihui Xu, Weishu Wang, Xu Shi, Gang Chen, and Shifei Zhao. "The Design of a Vapor-Condensing Plume Abatement System and Devices for Mechanical Draft Cooling Towers." Water 12, no. 4 (April 2, 2020): 1013. http://dx.doi.org/10.3390/w12041013.

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Cooling towers are widely used in many fields, but the generation of visible plumes has a serious impact on the environment. Moreover, the evaporation losses also cause a great waste of water. In this paper, a vapor-condensing plume abatement system was designed for a mechanical-draft cooling tower based on the mechanism of vapor plume generation. An effective method to achieve water-saving and eliminate the water fog generated in the cooling tower was proposed, and its feasibility was verified by using thermodynamic analysis. Next, the vapor-condensing plume abatement device was designed and used for both the confined space cooling tower (CSCT) and the free space cooling tower (FSCT). The surface type heat exchanger was adopted to design the vapor-condensing plume abatement device. Then a basic calculation flow and method were proposed to obtain thermodynamic operating parameters. According to the comparison between the results of theoretical calculation and practical engineering application, it was found that the designed vapor-condensing plume abatement system obviously benefits the water-saving of a mechanical-draft cooling tower and considerable economic benefits can be obtained. The contents presented provide the theoretical basis and technical support for the upgrade of the cooling tower and the design of the new cooling tower.

2

Serra, P., J. Palau, M. Varela, J. Esteve, and J. L. Morenza. "Characterization of hydroxyapatite laser ablation plumes by fast intensified CCD-imaging." Journal of Materials Research 10, no. 2 (February 1995): 473–78. http://dx.doi.org/10.1557/jmr.1995.0473.

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ArF excimer laser pulses (193 nm, 20 ns, 150 mJ) have been focused on a hydroxyapatite (HA) target in similar conditions to those normally used for thin film deposition. Fast intensified CCD images of HA laser ablation plumes have been taken in vacuum and under different water vapor pressures ranging from 0.01 mbar to 1 mbar. Images of HA ablation in vacuum have shown a plume freely expanding at a constant velocity of 2.3 × 106 cm/s. HA ablation under a water vapor pressure of 0.01 mbar has revealed an expansion behavior very similar to that of ablation in vacuum. Images taken under a water vapor pressure of 0.1 mbar have shown the formation of a shock structure in the plume. Finally, HA ablation under a water vapor pressure of 1 mbar has revealed the development of some irregularities in the shape of the plume.

3

Fiedler, V., F. Arnold, S. Ludmann, A. Minikin, T. Hamburger, L. Pirjola, A. Dörnbrack, and H. Schlager. "African biomass burning plumes over the Atlantic: aircraft based measurements and implications for H<sub>2</sub>SO<sub>4</sub> and HNO<sub>3</sub> mediated smoke particle activation." Atmospheric Chemistry and Physics 11, no. 7 (April 5, 2011): 3211–25. http://dx.doi.org/10.5194/acp-11-3211-2011.

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Abstract. Airborne measurements of trace gases and aerosol particles have been made in two aged biomass burning (BB) plumes over the East Atlantic (Gulf of Guinea). The plumes originated from BB in the Southern-Hemisphere African savanna belt. On the day of our measurements (13 August 2006), the plumes had ages of about 10 days and were respectively located in the middle troposphere (MT) at 3900–5500 m altitude and in the upper troposphere (UT) at 10 800–11 200 m. Probably, the MT plume was lifted by dry convection and the UT plume was lifted by wet convection. In the more polluted MT-plume, numerous measured trace species had markedly elevated abundances, particularly SO2 (up to 1400 pmol mol−1), HNO3 (5000–8000 pmol mol−1) and smoke particles with diameters larger than 270 nm (up to 2000 cm−3). Our MT-plume measurements indicate that SO2 released by BB had not experienced significant loss by deposition and cloud processes but rather had experienced OH-induced conversion to gas-phase sulfuric acid. By contrast, a significant fraction of the released NOy had experienced loss, most likely as HNO3 by deposition. In the UT-plume, loss of NOy and SO2 was more pronounced compared to the MT-plume, probably due to cloud processes. Building on our measurements and accompanying model simulations, we have investigated trace gas transformations in the ageing and diluting plumes and their role in smoke particle processing and activation. Emphasis was placed upon the formation of sulfuric acid and ammonium nitrate, and their influence on the activation potential of smoke particles. Our model simulations reveal that, after 13 August, the lower plume traveled across the Atlantic and descended to 1300 m and hereafter ascended again. During the travel across the Atlantic, the soluble mass fraction of smoke particles and their mean diameter increased sufficiently to allow the processed smoke particles to act as water vapor condensation nuclei already at very low water vapor supersaturations of only about 0.04%. Thereby, aged smoke particles had developed a potential to act as water vapor condensation nuclei in the formation of maritime clouds.

4

Hansen, C. J. "Enceladus' Water Vapor Plume." Science 311, no. 5766 (March 10, 2006): 1422–25. http://dx.doi.org/10.1126/science.1121254.

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5

Fiedler, V., F. Arnold, S. Ludmann, A. Minikin, L. Pirjola, A. Dörnbrack, and H. Schlager. "African biomass burning plumes over the Atlantic: aircraft based measurements and implications for H<sub>2</sub>SO<sub>4</sub> and HNO<sub>3</sub> mediated smoke particle activation." Atmospheric Chemistry and Physics Discussions 10, no. 3 (March 25, 2010): 7699–743. http://dx.doi.org/10.5194/acpd-10-7699-2010.

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Abstract. Airborne measurements of trace gases and aerosol particles have been made in two aged biomass burning (BB) plumes over the East Atlantic (Gulf of Guinea). The plumes originated from BB in the Southern Hemisphere African savanna belt. On the day of our measurements (13 August 2006), the plumes had ages of about 10 days and were respectively located in the middle troposphere (MT) at about 3000–5500 m altitude and in the upper troposphere (UT) at about 10 800–11 200 m. In the more polluted MT-plume, numerous measured trace species had markedly elevated abundances, particularly HNO3 (5000–8000 pmol/mol), SO2 (up to 1400 pmol/mol), and smoke particles with diameters larger than 250 nm (up to 2000 cm−3). Our MT-plume measurements indicate that SO2 released by BB had not experienced significant loss by deposition and cloud processes but rather had experienced OH-induced conversion to gas-phase sulfuric acid. By contrast, a large fraction of the released NOx had experienced loss, most likely as HNO3, by cloud processes and deposition. In the UT-plume, loss of NOy and SO2 by cloud processes and deposition was more pronounced compared to the MT-plume. Building on our measurements and accompanying model simulations, we have investigated trace gas transformations in the ageing and diluting plumes and their role in smoke particle processing and activation. Emphasis was placed upon the formation of sulfuric acid, nitric acid, and ammonium nitrate, and their influence on the activation potential of smoke particles. Our model simulations reveal that, after 13 August, the lower plume traveled across the Atlantic and descended to 1300 m and hereafter ascended again. During the travel across the Atlantic, the smoke particle mean diameter and sulfuric acid mass fraction increased sufficiently to allow the processed smoke particles to act as water vapor condensation nuclei already at very low water vapor supersaturations of only about 0.04%. Thereby, aged smoke particles had developed a potential to act as water vapor condensation nuclei in the formation of maritime clouds, including not only cumulus but even stratiform clouds.

6

Wen, Qian, and Xiang Dong Gao. "Analysis of Characteristic of Metal Vapor Plume during High-Power Disc Laser Welding." Applied Mechanics and Materials 201-202 (October 2012): 1126–29. http://dx.doi.org/10.4028/www.scientific.net/amm.201-202.1126.

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Metal vapor plume which induced during high power disc laser welding contains lots of information that related to the welding quality. Stainless steel 304 was taken as the experiment object for the high power disc laser welding experiment. A high-speed camera was used to capture the ultraviolet band and visible light band metal vapor plume images in the laser welding process. Image processing techniques such as median filtering, Wiener filtering, gray level threshold and image binarization were applied to get the images that only metal vapor plume was included. The ratio of the absolute value of coordinate difference between the centroid of plume and welding point was taken as the characteristic parameter. Welding experimental results and analysis of the changing of the ratio of the absolute value of coordinate difference between the centroid of plume and welding point confirmed that the welding quality could be monitored by the metal vapor plume during high power disc laser welding.

7

Bian, Qijing, Shantanu H. Jathar, John K. Kodros, Kelley C. Barsanti, Lindsay E. Hatch, Andrew A. May, Sonia M. Kreidenweis, and Jeffrey R. Pierce. "Secondary organic aerosol formation in biomass-burning plumes: theoretical analysis of lab studies and ambient plumes." Atmospheric Chemistry and Physics 17, no. 8 (April 28, 2017): 5459–75. http://dx.doi.org/10.5194/acp-17-5459-2017.

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Abstract. Secondary organic aerosol (SOA) has been shown to form in biomass-burning emissions in laboratory and field studies. However, there is significant variability among studies in mass enhancement, which could be due to differences in fuels, fire conditions, dilution, and/or limitations of laboratory experiments and observations. This study focuses on understanding processes affecting biomass-burning SOA formation in laboratory smog-chamber experiments and in ambient plumes. Vapor wall losses have been demonstrated to be an important factor that can suppress SOA formation in laboratory studies of traditional SOA precursors; however, impacts of vapor wall losses on biomass-burning SOA have not yet been investigated. We use an aerosol-microphysical model that includes representations of volatility and oxidation chemistry to estimate the influence of vapor wall loss on SOA formation observed in the FLAME III smog-chamber studies. Our simulations with base-case assumptions for chemistry and wall loss predict a mean OA mass enhancement (the ratio of final to initial OA mass, corrected for particle-phase wall losses) of 1.8 across all experiments when vapor wall losses are modeled, roughly matching the mean observed enhancement during FLAME III. The mean OA enhancement increases to over 3 when vapor wall losses are turned off, implying that vapor wall losses reduce the apparent SOA formation. We find that this decrease in the apparent SOA formation due to vapor wall losses is robust across the ranges of uncertainties in the key model assumptions for wall-loss and mass-transfer coefficients and chemical mechanisms.We then apply similar assumptions regarding SOA formation chemistry and physics to smoke emitted into the atmosphere. In ambient plumes, the plume dilution rate impacts the organic partitioning between the gas and particle phases, which may impact the potential for SOA to form as well as the rate of SOA formation. We add Gaussian dispersion to our aerosol-microphysical model to estimate how SOA formation may vary under different ambient-plume conditions (e.g., fire size, emission mass flux, atmospheric stability). Smoke from small fires, such as typical prescribed burns, dilutes rapidly, which drives evaporation of organic vapor from the particle phase, leading to more effective SOA formation. Emissions from large fires, such as intense wildfires, dilute slowly, suppressing OA evaporation and subsequent SOA formation in the near field. We also demonstrate that different approaches to the calculation of OA enhancement in ambient plumes can lead to different conclusions regarding SOA formation. OA mass enhancement ratios of around 1 calculated using an inert tracer, such as black carbon or CO, have traditionally been interpreted as exhibiting little or no SOA formation; however, we show that SOA formation may have greatly contributed to the mass in these plumes.In comparison of laboratory and plume results, the possible inconsistency of OA enhancement between them could be in part attributed to the effect of chamber walls and plume dilution. Our results highlight that laboratory and field experiments that focus on the fuel and fire conditions also need to consider the effects of plume dilution or vapor losses to walls.

8

Kiefer, Caroline M., Craig B. Clements, and Brian E. Potter. "Application of a Mini Unmanned Aircraft System for In Situ Monitoring of Fire Plume Thermodynamic Properties." Journal of Atmospheric and Oceanic Technology 29, no. 3 (March 1, 2012): 309–15. http://dx.doi.org/10.1175/jtech-d-11-00112.1.

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Abstract Direct measurements of wildland fire plume properties are rare because of difficult access to regions near the fire front and plume. Moisture released from combustion, in addition to added heat, can enhance buoyancy and convection, influencing fire behavior. In this study, a mini unmanned aircraft system (miniUAS) was used to obtain in situ measurements of temperature and relative humidity during a prescribed fire. The miniUAS was successfully maneuvered through the plume and its associated turbulence and provided observations of temperature and humidity profiles from near the centerline of the plume. Within the plume, the water vapor mixing ratio increased by 0.5–3.5 g kg−1 above ambient and was caused by the combustion of fuels. Potential temperature perturbations were on the order of 2–5 K. These results indicate that significant moisture and temperature enhancement can occur and may potentially modify convection dynamics of fire plumes.

9

Hamadi, Farida, and El Hachemi Amara. "Effect of Argon Ambient Gas Pressure on Plume Expansion Dynamics." Advanced Materials Research 227 (April 2011): 129–33. http://dx.doi.org/10.4028/www.scientific.net/amr.227.129.

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In this paper we present a numerical modeling of a nanosecond laser pulse interaction with a titanium target. We investigate the vapor plume formation and the influence of the ambient gas pressure on plume expansion dynamics. The vapor plume formation depends on the results of the heat transfer in the solid target modeling. The solid-liquid phase change is modeled by a two dimensional approach using an enthalpy formulation. The resulting plume expansion in the argon background gas is studied using the species transport model. The algebraic equations are discretized by the finite volume method implemented by Fluent CFD software [1]. The calculation results of plume expansion velocity, density, temperature and degree of ionization in the plume are presented.

10

Sahany, Sandeep, J. David Neelin, Katrina Hales, and Richard B. Neale. "Temperature–Moisture Dependence of the Deep Convective Transition as a Constraint on Entrainment in Climate Models." Journal of the Atmospheric Sciences 69, no. 4 (March 30, 2012): 1340–58. http://dx.doi.org/10.1175/jas-d-11-0164.1.

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Abstract Properties of the transition to strong deep convection, as previously observed in satellite precipitation statistics, are analyzed using parcel stability computations and a convective plume velocity equation. A set of alternative entrainment assumptions yields very different characteristics of the deep convection onset boundary (here measured by conditional instability and plume vertical velocity) in a bulk temperature–water vapor thermodynamic plane. In observations the threshold value of column water vapor above which there is a rapid increase in precipitation, referred to as the critical value, increases with temperature, but not as quickly as column saturation, and this can be matched only for cases with sufficiently strong entrainment. This corroborates the earlier hypothesis that entraining plumes can explain this feature seen in observations, and it places bounds on the lower-tropospheric entrainment. Examination of a simple interactive entrainment scheme in which a minimum turbulent entrainment is enhanced by a dynamic entrainment (associated with buoyancy-induced vertical acceleration) shows that the deep convection onset curve is governed by the prescribed minimum entrainment. Results from a 0.5° resolution version of the Community Climate System Model, whose convective parameterization includes substantial entrainment, yield a reasonable match to satellite observations in several respects. Temperature–water vapor dependence is seen to agree well with the plume calculations and with offline simulations performed using the convection scheme of the model. These findings suggest that the convective transition characteristics, including the onset curve in the temperature–water vapor plane, can provide a substantial constraint for entrainment assumptions used in climate model deep convective parameterizations.

11

Bredemeyer, Stefan, Franz-Georg Ulmer, Thor Hansteen, and Thomas Walter. "Radar Path Delay Effects in Volcanic Gas Plumes: The Case of Láscar Volcano, Northern Chile." Remote Sensing 10, no. 10 (September 21, 2018): 1514. http://dx.doi.org/10.3390/rs10101514.

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Modern volcano monitoring commonly involves Interferometric Synthetic Aperture Radar (InSAR) measurements to identify ground motions caused by volcanic activity. However, InSAR is largely affected by changes in atmospheric refractivity, in particular by changes which can be attributed to the distribution of water (H2O) vapor in the atmospheric column. Gas emissions from continuously degassing volcanoes contain abundant water vapor and thus produce variations in the atmospheric water vapor content above and downwind of the volcano, which are notably well captured by short-wavelength X-band SAR systems. These variations may in turn cause differential phase errors in volcano deformation estimates due to excess radar path delay effects within the volcanic gas plume. Inversely, if these radar path delay effects are better understood, they may be even used for monitoring degassing activity, by means of the precipitable water vapor (PWV) content in the plume at the time of SAR acquisitions, which may provide essential information on gas plume dispersion and the state of volcanic and hydrothermal activity. In this work we investigate the radar path delays that were generated by water vapor contained in the volcanic gas plume of the persistently degassing Láscar volcano, which is located in the dry Atacama Desert of Northern Chile. We estimate water vapor contents based on sulfur dioxide (SO2) emission measurements from a scanning UV spectrometer (Mini-DOAS) station installed at Láscar volcano, which were scaled by H2O/SO2 molar mixing ratios obtained during a multi-component Gas Analyzer System (Multi-GAS) survey on the crater rim of the volcano. To calculate the water vapor content in the downwind portion of the plume, where an increase of water vapor is expected, we further applied a correction involving estimation of potential evaporation rates of water droplets governed by turbulent mixing of the condensed volcanic plume with the dry atmosphere. Based on these estimates we obtain daily average PWV contents inside the volcanic gas plume of 0.2–2.5 mm equivalent water column, which translates to a slant wet delay (SWD) in DInSAR data of 1.6–20 mm. We used these estimates in combination with our high resolution TerraSAR-X DInSAR observations at Láscar volcano, in order to demonstrate the occurrence of repeated atmospheric delay patterns that were generated by volcanic gas emissions. We show that gas plume related refractivity changes are significant and detectable in DInSAR measurements. Implications are two-fold: X-band satellite radar observations also contain information on the degassing state of a volcano, while deformation signals need to be interpreted with care, which has relevance for volcano observations at Láscar and for other sites worldwide.

12

Zhuang, Jiawei, Daniel J. Jacob, and Sebastian D. Eastham. "The importance of vertical resolution in the free troposphere for modeling intercontinental plumes." Atmospheric Chemistry and Physics 18, no. 8 (May 2, 2018): 6039–55. http://dx.doi.org/10.5194/acp-18-6039-2018.

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Abstract. Chemical plumes in the free troposphere can preserve their identity for more than a week as they are transported on intercontinental scales. Current global models cannot reproduce this transport. The plumes dilute far too rapidly due to numerical diffusion in sheared flow. We show how model accuracy can be limited by either horizontal resolution (Δx) or vertical resolution (Δz). Balancing horizontal and vertical numerical diffusion, and weighing computational cost, implies an optimal grid resolution ratio (Δx ∕ Δz)opt ∼ 1000 for simulating the plumes. This is considerably higher than current global models (Δx ∕ Δz ∼ 20) and explains the rapid plume dilution in the models as caused by insufficient vertical resolution. Plume simulations with the Geophysical Fluid Dynamics Laboratory Finite-Volume Cubed-Sphere Dynamical Core (GFDL-FV3) over a range of horizontal and vertical grid resolutions confirm this limiting behavior. Our highest-resolution simulation (Δx ≈ 25 km, Δz ≈ 80 m) preserves the maximum mixing ratio in the plume to within 35 % after 8 days in strongly sheared flow, a drastic improvement over current models. Adding free tropospheric vertical levels in global models is computationally inexpensive and would also improve the simulation of water vapor.

13

Randel, William J., Benjamin R. Johnston, John J. Braun, Sergey Sokolovskiy, Holger Vömel, Aurelien Podglajen, and Bernard Legras. "Stratospheric Water Vapor from the Hunga Tonga–Hunga Ha’apai Volcanic Eruption Deduced from COSMIC-2 Radio Occultation." Remote Sensing 15, no. 8 (April 20, 2023): 2167. http://dx.doi.org/10.3390/rs15082167.

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The eruption of the Hunga Tonga–Hunga Ha’apai (HTHH) volcano on 15 January 2022 injected large amounts of water vapor (H2O) directly into the stratosphere. While normal background levels of stratospheric H2O are not detectable in radio occultation (RO) measurements, effects of the HTHH eruption are clearly observed as anomalous refractivity profiles from COSMIC-2, suggesting the possibility of detecting the HTHH H2O signal. To separate temperature and H2O effects on refractivity, we use co-located temperature observations from the Microwave Limb Sounder (MLS) to constrain a simplified H2O retrieval. Our results show enhancements of H2O up to ~2500–3500 ppmv in the stratosphere (~29–33 km) in the days following the HTHH eruption, with propagating patterns that follow the dispersing volcanic plume. The stratospheric H2O profiles derived from RO are in reasonable agreement with limited radiosonde observations over Australia. The H2O profiles during the first few days after the eruption show descent of the plume at a rate of ~−1 km/day, likely due to strong radiative cooling (~−10 K/day) induced by high H2O concentrations; slower descent (~−200 m/day) is observed over the following week as the plume disperses. The total mass of H2O injected by HTHH is estimated as 110 ± 14 Tg from measurements in the early plumes during 16–18 January, which equates to approximately 8% of the background global mass of stratospheric H2O. These RO measurements provide novel quantification of the unprecedented H2O amounts and the plume evolution during the first week after the HTHH eruption.

14

Sorenson, Blake T., Jeffrey S. Reid, Jianglong Zhang, Robert E. Holz, William L. Smith Sr., and Amanda Gumber. "Thermal infrared observations of a western United States biomass burning aerosol plume." Atmospheric Chemistry and Physics 24, no. 2 (January 29, 2024): 1231–48. http://dx.doi.org/10.5194/acp-24-1231-2024.

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Abstract. Biomass burning smoke particles, due to their submicron particle size in relation to the average thermal infrared (TIR) wavelength, theoretically have negligible signals at the TIR channels. However, nearly instantaneous longwave (LW) signatures of thick smoke plumes can be frequently observed at the TIR channels from remotely sensed data, including at 10.6 µm (IR window), as well as in water-vapor-sensitive wavelengths at 7.3, 6.8, and 6.3 µm (e.g., lower, middle, and upper troposphere). We systematically evaluated multiple hypotheses as to causal factors of these IR signatures of biomass burning smoke using a combination of data from the Aqua MODerate resolution Imaging Spectroradiometer (MODIS), Aqua Cloud and the Earth Radiant Energy System (CERES), Geostationary Operational Environmental Satellite 16/17 (GOES-16/17) Advanced Baseline Imager, and Suomi-NPP Visible Infrared Imaging Radiometer Suite (VIIRS) and Cross-track Infrared Sounder (CrIS). The largely clear transmission of light through wildfire smoke in the near infrared indicates that coarse or giant ash particles are unlikely to be the dominant cause. Rather, clear signals in water vapor and TIR channels suggest that both co-transported water vapor injected to the middle to upper troposphere and surface cooling by the reduction of surface radiation by the plume are more significant, with the surface cooling effect of smoke aloft being the most dominant. Giving consideration of the smoke impacts on TIR and longwave, CERES indicates that large wildfire aerosol plumes are more radiatively neutral. Further, this smoke-induced TIR signal may be used to map very optically thick smoke plumes, where traditional aerosol retrieval methods have difficulties.

15

POVITSKY, ALEX. "FLUID DYNAMICS ISSUES IN SYNTHESIS OF CARBON NANOTUBES." International Journal of Nanoscience 04, no. 01 (February 2005): 73–98. http://dx.doi.org/10.1142/s0219581x0500295x.

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The majority of carbon nanotubes' synthesis processes occur in the presence of fluid (liquid, gas, plasma, or multi-phase flow) that may function as a carrier of catalyst particles, feedstock of carbon, and the heating or cooling agent. The fluid motion defines the temperature of catalyst particles and the local chemical composition of the fluid that determines the success of synthesis of high-purity nanotubes. In this review paper, the laser ablation process, high-pressure carbon oxide process, and chemical vapor deposition process are considered from the prospective of fluid dynamics modeling. The multi-model approach should be used for concurrent rendering of different areas of computational domain by different models and/or different time steps for the same model. For multiple plume ejection in laser ablation, the near-target area could be rendered by molecular dynamics approach whereas continuous gas dynamics algorithms should be employed to simulate plume dynamics of previously ejected plumes apart of the target. Such an approach combines continuous mechanics of multi-species flow of feedstock gas or plume; micro-fluidic flow model that is needed to find heat and mass transfer rate to catalysts in presence of individual nanotubes in close proximity to each other; and molecular dynamics of evaporation and ejection of plume in laser ablation.

16

Gallagher, Neal B., Barry M. Wise, and David M. Sheen. "Error Analysis for Estimation of Trace Vapor Concentration Pathlength in Stack Plumes." Applied Spectroscopy 57, no. 6 (June 2003): 614–21. http://dx.doi.org/10.1366/000370203322005283.

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Near-infrared hyperspectral imaging is finding utility in remote sensing applications such as detection and quantification of chemical vapor effluents in stack plumes. Optimizing the sensing system or quantification algorithms is difficult because reference images are rarely well characterized. The present work uses a radiance model for a down-looking scene and a detailed noise model for dispersive and Fourier transform spectrometers to generate well-characterized synthetic data. These data were used with a classical least-squares-based estimator in an error analysis to obtain estimates of different sources of concentration-pathlength quantification error in the remote sensing problem. Contributions to the overall quantification error were the sum of individual error terms related to estimating the background, atmospheric corrections, plume temperature, and instrument signal-to-noise ratio. It was found that the quantification error depended strongly on errors in the background estimate and second-most on instrument signal-to-noise ratio. Decreases in net analyte signal (e.g., due to low analyte absorbance or increasing the number of analytes in the plume) led to increases in the quantification error as expected. These observations have implications on instrument design and strategies for quantification. The outlined approach could be used to estimate detection limits or perform variable selection for given sensing problems.

17

Miller, Steven D., Louie D. Grasso, Qijing Bian, Sonia M. Kreidenweis, Jack F. Dostalek, Jeremy E. Solbrig, Jennifer Bukowski, et al. "<i>A Tale of Two Dust Storms</i>: analysis of a complex dust event in the Middle East." Atmospheric Measurement Techniques 12, no. 9 (September 24, 2019): 5101–18. http://dx.doi.org/10.5194/amt-12-5101-2019.

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Abstract. Lofted mineral dust over data-sparse regions presents considerable challenges to satellite-based remote sensing methods and numerical weather prediction alike. The southwest Asia domain is replete with such examples, with its diverse array of dust sources, dust mineralogy, and meteorologically driven lofting mechanisms on multiple spatial and temporal scales. A microcosm of these challenges occurred over 3–4 August 2016 when two dust plumes, one lofted within an inland dry air mass and another embedded within a moist air mass, met over the southern Arabian Peninsula. Whereas conventional infrared-based techniques readily detected the dry air mass dust plume, they experienced marked difficulties in detecting the moist air mass dust plume, becoming apparent when visible reflectance revealed the plume crossing over an adjacent dark water background. In combining information from numerical modeling, multi-satellite and multi-sensor observations of lofted dust and moisture profiles, and idealized radiative transfer simulations, we develop a better understanding of the environmental controls of this event, characterizing the sensitivity of infrared-based dust detection to column water vapor, dust vertical extent, and dust optical properties. Differences in assumptions of dust complex refractive index translate to variations in the sign and magnitude of the split-window brightness temperature difference commonly used for detecting mineral dust. A multi-sensor technique for mitigating the radiative masking effects of water vapor via modulation of the split-window dust-detection threshold, predicated on idealized simulations tied to these driving factors, is proposed and demonstrated. The new technique, indexed to an independent description of the surface-to-500 hPa atmospheric column moisture, reveals parts of the missing dust plume embedded in the moist air mass, with the best performance realized over land surfaces.

18

Hirata, R. C. A., and R. W. Cleary. "The Use of Soil-Gas Sampling in the Study of Groundwater Pollution by Volatile Solvents (VOC): The Example of the Porto Feliz (São Paulo, Brazil) Case." Water Science and Technology 24, no. 11 (December 1, 1991): 127–38. http://dx.doi.org/10.2166/wst.1991.0345.

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In 1983, a serious accident occurred in Porto Feliz, São Paulo, Brazil when the rupture of a storage tank released 400,000 litres of volatile organic solvents. A large portion of the underlying aquifer was contaminated including some deep wells and shallow hand-dug wells. Soil-gas sampling was the technique used to evaluate the degree and extent of contamination. The method is based on the analysis of small quantities of soil vapors extracted at shallow depths. The origin of these vapors is the underlying contaminated groundwater and the vapor concentration distribution reflects the degree and extent of aquifer contamination. Other techniques were rejected since the physico-chemical characteristics of the pollutants did not allow their detection by traditional geophysical methods and the thick unsaturated zone and difficult geology would have resulted in exorbitant drilling costs for monitoring wells. The use of soil-gas sampling allowed mapping of the pollution plume, defining its two-dimensional shape and location. Vapor analyses at different depths permitted the establishment of concentration gradients and an estimation of vertical vapor flow behavior in the unsaturated zone as well as surface losses by volatilization. Water levels in existing wells made it possible to construct potentiometric surface maps, defining the groundwater flow pattern. Periodic groundwater quality monitoring furnished data for the evaluation of the plume migration velocity and the influence of rainfall on the increase of pollutant concentrations in the aquifer. The groundwater pollutant concentrations obtained gave a good correlation between the two means.

19

Mihai, Sabin, Diana Chioibasu, Muhammad Arif Mahmood, Liviu Duta, Marc Leparoux, and Andrei C. Popescu. "Real-Time Defects Analyses Using High-Speed Imaging during Aluminum Magnesium Alloy Laser Welding." Metals 11, no. 11 (November 22, 2021): 1877. http://dx.doi.org/10.3390/met11111877.

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In this study a continuous wave Ytterbium-doped Yttrium Aluminum Garnet (Yb: YAG) disk laser has been used for welding of AlMg3 casted alloy. A high-speed imaging camera has been employed to record hot vapor plume features during the process. The purpose was to identify a mechanism of pores detection in real-time based on correlations between metallographic analyses and area/intensity of the hot vapor in various locations of the samples. The pores formation and especially the position of these pores had to be kept under control in order to weld thick samples. Based on the characterization of the hot vapor, it has been found that the increase of the vapor area that exceeded a threshold value (18.5 ± 1 mm2) was a sign of pores formation within the weld seam. For identification of the pores’ locations during welding, the monitored element was the hot vapor intensity. The hot vapor core spots having a grayscale level reaching 255 was associated with the formation of a local pore. These findings have been devised based on correlation between pores placement in welds cross-section microscopy images and the hot vapor plume features in those respective positions.

20

Tanaka, K. A., A. Hassanein, Y. Hirooka, T. Kono, S. Misaki, T. Ohishi, A. Sunahara, and S. Tanaka. "Carbon Plume Stagnation: Platform for Vapor Shield Study." Fusion Science and Technology 60, no. 1 (July 2011): 329–33. http://dx.doi.org/10.13182/fst11-a12374.

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21

Podrabinnik, Pavel A., Alexander E. Shtanko, Roman S. Khmyrov, Andrey D. Korotkov, and Andrey V. Gusarov. "Interferometry of Gas-Phase Flows during Selective Laser Melting." Applied Sciences 10, no. 1 (December 27, 2019): 231. http://dx.doi.org/10.3390/app10010231.

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Gas-phase flows occurring in a plume in a processing zone during selective laser melting (SLM) can significantly affect the quality of the process. To further enhance SLM performance, the characteristics of the flows should be considered. In this article, the vapor-gas jet emerging from the laser processing zone was studied. It was visualized by interferometry to evaluate flow velocity, geometry and changes in refractory index depending on laser power. The velocity and pressure fields of the vapor jet and the entrained ambient gas were estimated by mathematical modeling. It was shown that the increase of laser power led to higher jet velocity and greater change in its refractory index. The latter also was used to evaluate the content of metal vapor in the plume and its influence on the absorption of laser radiation.

22

Puretzky, A. A., D. B. Geohegan, G. B. Hurst, M. V. Buchanan, and B. S. Luk'yanchuk. "Imaging of Vapor Plumes Produced by Matrix Assisted Laser Desorption: A Plume Sharpening Effect." Physical Review Letters 83, no. 2 (July 12, 1999): 444–47. http://dx.doi.org/10.1103/physrevlett.83.444.

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23

Wen, Qian, and Xiang Dong Gao. "Analysis of Image Characteristics of Plume and Spatter of High Power Disk Laser Welding Based on K-L Transform." Advanced Materials Research 532-533 (June 2012): 330–34. http://dx.doi.org/10.4028/www.scientific.net/amr.532-533.330.

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Metal vapor plume and spatters are the important phenomena in the process of high power disk laser welding, and there exists a close relationship with the welding stability. The images of metal vapor plume and spatters which captured by a high speed camera during high power disk laser welding were analyzed in this experiment. Image processing techniques such as median filtering, Wiener filtering, gray level threshold and lightness transform were used to process the images so that the image characteristic parameters such as the area and number of spatters in an image, the average gray, mean value, variance and entropy of a spatter gray level image and the coordinate ratio of the centriod of plume and the welding point can be extracted. To reflect the actual welding results obviously by those characteristic parameters, K-L transform method was used to get a new set of characteristic parameters. Experimental results showed that this new set of characteristic parameters could reflect the actual welding effectively.

24

Pistone, Kristina, Paquita Zuidema, Robert Wood, Michael Diamond, Arlindo M. da Silva, Gonzalo Ferrada, Pablo E. Saide, et al. "Exploring the elevated water vapor signal associated with the free tropospheric biomass burning plume over the southeast Atlantic Ocean." Atmospheric Chemistry and Physics 21, no. 12 (June 29, 2021): 9643–68. http://dx.doi.org/10.5194/acp-21-9643-2021.

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Abstract. In southern Africa, widespread agricultural fires produce substantial biomass burning (BB) emissions over the region. The seasonal smoke plumes associated with these emissions are then advected westward over the persistent stratocumulus cloud deck in the southeast Atlantic (SEA) Ocean, resulting in aerosol effects which vary with time and location. Much work has focused on the effects of these aerosol plumes, but previous studies have also described an elevated free tropospheric water vapor signal over the SEA. Water vapor influences climate in its own right, and it is especially important to consider atmospheric water vapor when quantifying aerosol–cloud interactions and aerosol radiative effects. Here we present airborne observations made during the NASA ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) campaign over the SEA Ocean. In observations collected from multiple independent instruments on the NASA P-3 aircraft (from near-surface to 6–7 km), we observe a strongly linear correlation between pollution indicators (carbon monoxide (CO) and aerosol loading) and atmospheric water vapor content, seen at all altitudes above the boundary layer. The focus of the current study is on the especially strong correlation observed during the ORACLES-2016 deployment (out of Walvis Bay, Namibia), but a similar relationship is also observed in the August 2017 and October 2018 ORACLES deployments. Using reanalyses from the European Centre for Medium-Range Weather Forecasts (ECMWF) and Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2), and specialized WRF-Chem simulations, we trace the plume–vapor relationship to an initial humid, smoky continental source region, where it mixes with clean, dry upper tropospheric air and then is subjected to conditions of strong westward advection, namely the southern African easterly jet (AEJ-S). Our analysis indicates that air masses likely left the continent with the same relationship between water vapor and carbon monoxide as was observed by aircraft. This linear relationship developed over the continent due to daytime convection within a deep continental boundary layer (up to ∼5–6 km) and mixing with higher-altitude air, which resulted in fairly consistent vertical gradients in CO and water vapor, decreasing with altitude and varying in time, but this water vapor does not originate as a product of the BB combustion itself. Due to a combination of conditions and mixing between the smoky, moist continental boundary layer and the dry and fairly clean upper-troposphere air above (∼6 km), the smoky, humid air is transported by strong zonal winds and then advected over the SEA (to the ORACLES flight region) following largely isentropic trajectories. Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT) back trajectories support this interpretation. This work thus gives insights into the conditions and processes which cause water vapor to covary with plume strength. Better understanding of this relationship, including how it varies spatially and temporally, is important to accurately quantify direct, semi-direct, and indirect aerosol effects over this region.

25

Kerfoot, William B., and Jon R. Soderberg. "PNEUMATIC HAMMER SOIL VAPOR PROBES AND MINIATURE PIEZOMETERS FOR GASOLINE SPILL DELINEATION AND CLEANUP." International Oil Spill Conference Proceedings 1989, no. 1 (February 1, 1989): 115–18. http://dx.doi.org/10.7901/2169-3358-1989-1-115.

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ABSTRACT In a new twist on an old procedure, pneumatically injected miniature well points may change soil investigations much as nail guns have changed carpentry. Soil vapor analysis has increasingly gained attention as a means of locating and monitoring subsurface gasoline spills. Accurate depiction of the plume position requires reproducible vapor detection and monitoring. In addition, static water level needs to be determined to understand flow direction. Miniature aluminum slitted well points can be mass-produced by computer-aided production facilities to create low-cost identical copies about 10 cm in length. The small points can be inserted into shafts and injected into the ground. The shaft is then pulled back, leaving a flexible teflon or polypropylene tubing attached. A gasoline spill at Falmouth, Cape Cod, Massachusetts, provided an opportunity to test the use of the injected “shield” points. More than 40 vapor points were installed in two days during four transects across a product plume located 10 m below grade.

26

Fiedler, V., F. Arnold, H. Schlager, A. Dörnbrack, L. Pirjola, and A. Stohl. "East Asian SO<sub>2</sub> pollution plume over Europe – Part 2: Evolution and potential impact." Atmospheric Chemistry and Physics 9, no. 14 (July 20, 2009): 4729–45. http://dx.doi.org/10.5194/acp-9-4729-2009.

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Abstract. We report on the first observation-based case study of an aged East Asian anthropogenic SO2 pollution plume over Europe. Our airborne measurements in that plume detected highly elevated SO2 mole fractions (up to 900 pmol/mol) between about 5000 and 7000 m altitude. Here, we focus on investigations of the origin, dispersion, evolution, conversion, and potential impact of the observed excess SO2. In particular, we investigate SO2 conversion to gas-phase sulfuric acid and sulfuric acid aerosols. Our FLEXPART and LAGRANTO model simulations, along with additional trace gas measurements, suggest that the plume originated from East Asian fossil fuel combustion sources and, 8–7 days prior to its arrival over Europe, ascended over the coast region of central East Asia to 9000 m altitude, probably in a cyclonic system with an associated warm conveyor belt. During this initial plume ascent a substantial fraction of the initially available SO2 must have escaped from removal by cloud processes. Hereafter, while mostly descending slowly, the plume experienced advection across the North Pacific, North America and the North Atlantic. During its upper troposphere travel, clouds were absent in and above the plume and OH-induced gas-phase conversion of SO2 to gas-phase sulfuric acid (GSA) was operative, followed by GSA nucleation and condensation leading to sulfuric acid aerosol formation and growth. Our AEROFOR model simulations indicate that numerous large sulfuric acid aerosol particles were formed, which at least temporarily, caused substantial horizontal visibility degradation, and which have the potential to act as water vapor condensation nuclei in liquid water cloud formation, already at water vapor supersaturations as low as about 0.1%. Our AEROFOR model simulations also indicate that those fossil fuel combustion generated soot particles, which have survived cloud induced removal during the initial plume ascent, have experienced extensive H2SO4/H2O-coating, during upper troposphere plume travel. This coating may have dramatically altered the morphology and markedly increased the light absorption efficiency of soot particles.

27

Essien, M., and D. M. Keicher. "Enhanced imaging of a pulsed Nd:YAG metal vapor plume." Journal of Laser Applications 10, no. 2 (April 1998): 85–89. http://dx.doi.org/10.2351/1.521832.

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28

Liu, Gui Qian, and Xiang Dong Gao. "Investigation of Image Characteristics of Plume and Spatters during High-Power Disk Laser Welding." Advanced Materials Research 709 (June 2013): 301–4. http://dx.doi.org/10.4028/www.scientific.net/amr.709.301.

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During high-power laser welding process, the workpiece produces metal vapor because of the laser irradiation. The characteristics of metal vapor are related to the quality and stability of welding and the utilization of the laser power. An approach of analyzing the characteristics of metal vapor was researched during high-power disk laser bead-on-plate welding of Type 304 austenitic stainless steel plates at a continuous wave laser power of 10 kW. A high-speed photography was used to capture metal vapor dynamic images. Metal vapor area, beam path, swing angle are calculated by image processing, which is the foundation for monitoring and control of welding quality in real time.

29

Thorpe, Andrew K., Christian Frankenberg, David R. Thompson, Riley M. Duren, Andrew D. Aubrey, Brian D. Bue, Robert O. Green, et al. "Airborne DOAS retrievals of methane, carbon dioxide, and water vapor concentrations at high spatial resolution: application to AVIRIS-NG." Atmospheric Measurement Techniques 10, no. 10 (October 19, 2017): 3833–50. http://dx.doi.org/10.5194/amt-10-3833-2017.

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Abstract. At local scales, emissions of methane and carbon dioxide are highly uncertain. Localized sources of both trace gases can create strong local gradients in its columnar abundance, which can be discerned using absorption spectroscopy at high spatial resolution. In a previous study, more than 250 methane plumes were observed in the San Juan Basin near Four Corners during April 2015 using the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) and a linearized matched filter. For the first time, we apply the iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS) method to AVIRIS-NG data and generate gas concentration maps for methane, carbon dioxide, and water vapor plumes. This demonstrates a comprehensive greenhouse gas monitoring capability that targets methane and carbon dioxide, the two dominant anthropogenic climate-forcing agents. Water vapor results indicate the ability of these retrievals to distinguish between methane and water vapor despite spectral interference in the shortwave infrared. We focus on selected cases from anthropogenic and natural sources, including emissions from mine ventilation shafts, a gas processing plant, tank, pipeline leak, and natural seep. In addition, carbon dioxide emissions were mapped from the flue-gas stacks of two coal-fired power plants and a water vapor plume was observed from the combined sources of cooling towers and cooling ponds. Observed plumes were consistent with known and suspected emission sources verified by the true color AVIRIS-NG scenes and higher-resolution Google Earth imagery. Real-time detection and geolocation of methane plumes by AVIRIS-NG provided unambiguous identification of individual emission source locations and communication to a ground team for rapid follow-up. This permitted verification of a number of methane emission sources using a thermal camera, including a tank and buried natural gas pipeline.

30

Wang, Teng, and Xiang Dong Gao. "Color Image Segmentation of Plume for Monitoring Disk Laser Welding Process." Applied Mechanics and Materials 201-202 (October 2012): 166–69. http://dx.doi.org/10.4028/www.scientific.net/amm.201-202.166.

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During deep penetration laser welding, changes in the metal vapor plume contain information about the stability of welding process. A high-speed camera was used to online monitor the welding process in order to detect the laser welding defects. A color segmentation clustering algorithm based on HSI color space was proposed for processing the recorded welding sequences. The effectiveness of algorithms based on different model is discussed, welding experimental results showed that the proposed algorithm could achieve better image segmentation, and it highlighted the edge of the metal vapor details in the image.

31

Shcheglov, P. Yu, A. V. Gumenyuk, I. B. Gornushkin, M. Rethmeier, and V. N. Petrovskiy. "Vapor–plasma plume investigation during high-power fiber laser welding." Laser Physics 23, no. 1 (November 20, 2012): 016001. http://dx.doi.org/10.1088/1054-660x/23/1/016001.

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32

Powell, A., P. Minson, G. Trapaga, and U. Pal. "Mathematical modeling of vapor-plume focusing in electron-beam evaporation." Metallurgical and Materials Transactions A 32, no. 8 (August 2001): 1959–66. http://dx.doi.org/10.1007/s11661-001-0008-y.

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33

Ebel, Denton S., and Lawrence Grossman. "Spinel-bearing spherules condensed from the Chicxulub impact-vapor plume." Geology 33, no. 4 (2005): 293. http://dx.doi.org/10.1130/g21136.1.

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34

Thareja, Raj K., A. Mohanta, D. Yadav, and A. Kushwaha. "Synthesis and Characterization of Nanoparticles and Nanocrystalline Functional Films." Materials Science Forum 636-637 (January 2010): 709–13. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.709.

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This work reports on spectroscopic investigations of interaction of an expanding laser ablated plume of aluminum, zinc, graphite with ambient atmosphere of oxygen and nitrogen gas and the formation of nitrides and oxides. The ambient pressure and fluence dependence on the reactive process occurring in the ablated plume responsible for formation of oxides and nitrides is discussed. Fast photography/imaging technique using intensified charge coupled device (ICCD) is gaining importance as a diagnostic tool for understanding the dynamics of the expanding plasma plume and the gas phase nanoparticle synthesis, thus providing a novel way to understand the transportation of nanoparticles and of control of particle size. Two dimensional images of the expanding plasma plume were captured using ICCD to understand the role of vapor and shock temperature. A comprehensive study done on oxide and nitrides films using pulsed laser deposition technique for possible laser oscillations in UV region of electromagnetic spectrum is presented.

35

Raja Kumar, M., JM Jouvard, I. Tomashchuk, and P. Sallamand. "Vapor plume and melted zone behavior during dissimilar laser welding of titanium to aluminum alloy." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 234, no. 5 (March 8, 2020): 681–96. http://dx.doi.org/10.1177/1464420720907936.

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The present study deals with continuous Yb:YAG laser welding of pure titanium to aluminum alloy A5754 performed with different beam offsets to the joint line. Spectroscopic and morphological characterization of vapor plume exiting the keyhole was combined with post-mortem observation and energy-dispersive X-ray spectroscopy (EDX) analysis of the welds. The laser beam centered on the joint line resulted in periodic transversal inclination of a vapor jet on the aluminum side associated with a local increase of melt width and an intense spatter formation. Such behavior can be attributed to the instability of the keyhole wall from the aluminum side. The beam offset on the titanium side led to the stabilization of vapor plume, the attenuation of spattering, and a minimal mixing between the two liquid metals. On the contrary, the beam offset on the aluminum side produced a violent formation of spatters and a highly unstable, diffuse vapor jet. In this case, the liquid metals underwent a violent mixing that was progressively reduced along with the decrease in quantity of melted Ti. The observed spectral regions contained the emission peaks of neutral Ti and Mn. Very few emission lines of Al were observed, because they require higher excitation energies compared to Ti and Mn. Boltzmann linearization using Ti emission peaks allowed the estimation of vapor temperature to be between 5000 and 6000 K, except for the welds with the beam offset on Al.

36

Vömel, Holger, Stephanie Evan, and Matt Tully. "Water vapor injection into the stratosphere by Hunga Tonga-Hunga Ha’apai." Science 377, no. 6613 (September 23, 2022): 1444–47. http://dx.doi.org/10.1126/science.abq2299.

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Large volcanic eruptions, although rare events, can influence the chemistry and the dynamics of the stratosphere for several years after the eruption. Here we show that the eruption of the submarine volcano Hunga Tonga-Hunga Ha’apai on 15 January 2022 injected at least 50 teragrams of water vapor directly into the stratosphere. This event raised the amount of water vapor in the developing stratospheric plume by several orders of magnitude and possibly increased the amount of global stratospheric water vapor by more than 5%. This extraordinary eruption may have initiated an atmospheric response different from that of previous well-studied large volcanic eruptions.

37

Sharma, H., M. M. Hedman, and S. Vahidinia. "New Insights into Variations in Enceladus Plume Particle Launch Velocities from Cassini-VIMS Spectral Data." Planetary Science Journal 4, no. 6 (June 1, 2023): 108. http://dx.doi.org/10.3847/psj/acd5d4.

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Abstract Enceladus’s plume consists mainly of a mixture of water vapor and solid ice particles that may originate from a subsurface ocean. The physical processes underlying Enceladus’s plume particle dynamics are still being debated, and quantifying the particles’ size distribution and launch velocities can help constrain these processes. Cassini’s Visual and Infrared Mapping Spectrometer observed the Enceladus plume over a wavelength range of 0.9–5.0 μm for a significant fraction of Enceladus’s orbital period on three dates in the summer of 2017. We find that the relative brightness of the plume on these different dates varies with wavelength, implying that the particle size distribution in the plume changes over time. These observations also enable us to study how the particles’ launch velocities vary with time and observed wavelength. We find that the typical launch velocity of particles remains between 140 and 148 m s−1 at wavelengths between 1.2 and 3.7 μm. This may not be consistent with prior models where particles are only accelerated by interactions with the vent walls and gas and could imply that mutual particle collisions close to the vent are more important than previously recognized.

38

Shusser, Michael. "Kinetic Theory Analysis of Laser Ablation of Carbon." Journal of Nanoscience and Nanotechnology 8, no. 7 (July 1, 2008): 3781–89. http://dx.doi.org/10.1166/jnn.2008.15838.

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The paper presents a model of ablation of carbon by a nanosecond laser pulse that considers the kinetics of the process. The model approximates the process as sublimation and combines conduction heat transfer in the target with the gas dynamics of the ablated plume which are coupled through the boundary conditions at the interface. The ablated mass flux and the temperature of the ablating material are obtained from the conservation relations at the interface derived from the momentum solution of the Boltzmann equation for arbitrary strong evaporation. The effects of laser intensity and ambient pressure on the ablated mass flux and parameters of vapor plume are studied. It is shown that most of the time the ablation rate is restricted by the kinetic theory limitation on the maximum mass flux that can be attained in a phase-change process. This fact makes the model tolerant of possible inaccuracies in calculating the saturation pressure of carbon vapor.

39

Asmann, Marcus, Robert F. Cook, Joachim V. Heberlein, and Emil Pfender. "Chemical vapor deposition of an aluminum nitride–diamond composite in a triple torch plasma reactor." Journal of Materials Research 16, no. 2 (February 2001): 469–77. http://dx.doi.org/10.1557/jmr.2001.0070.

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An aluminum nitride–diamond composite has been produced by sequential deposition of AlN and diamond in a triple torch plasma reactor (TTPR). AlN was deposited from AlN powder by injection into the argon–nitrogen, converging plasma plume of a TTPR. Velocity and temperature profiles of the converging plasma plume, obtained by enthalpy probe measurements, were used to show that the powder decomposed prior to reaching the substrate. Diamond was deposited in an argon–hydrogen–methane system onto the existing AlN film. Characterization of an AlN–diamond–AlN composite indicated a Vickers hardness of 18.6 GPa and a modulus of elasticity of 245–282 GPa.

40

AFANASIEV, Y. V., V. A. ISAKOV, I. N. ZAVESTOVSKAYA, B. N. CHICHKOV, F. VON ALVENSLEBEN, and H. WELLING. "Hydrodynamic model for UV laser ablation of polymers." Laser and Particle Beams 17, no. 4 (October 1999): 585–90. http://dx.doi.org/10.1017/s0263034699174019.

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The applicability of hydrodynamic models for theoretical description of UV laser ablation of polymers is studied. The plume formation is considered as a first-kind phase transition. In case of strongly absorbing polymers this phase transition occurs as a surface evaporation, and in case of weakly absorbing polymers as a bulk evaporation. The vapor plume is assumed to be transparent for laser radiation, and its expansion is described by the isoentropic hydrodynamic equations. New analytical expressions for ablation (etch) depths per pulse are obtained, which are in good agreement with the available experimental data (Afanasiev et al. 1997).

41

Ho, W. F., C. W. Ng, and N. H. Cheung. "Spectrochemical Analysis of Liquids Using Laser-Induced Plasma Emissions: Effects of Laser Wavelength." Applied Spectroscopy 51, no. 1 (January 1997): 87–91. http://dx.doi.org/10.1366/0003702971938812.

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The plasma plume emissions produced by pulsed (∼ 10 ns) laser ablation of liquid jets were monitored for spectrochemical analysis. Laser wavelengths at 532 and 193 nm were used, and sodium was the test analyte. As expected, the 532-nm laser pulse produced very intense plasma continuum emissions that masked the sodium signal for the first hundred nanoseconds, especially near the bright core of the vapor plume. Neither time-gating nor spatial masking could significantly improve the single-shot signal-to-noise ratio, since the transient nature of the emissions placed stringent demands on timing precision while the small size of the plume required accurate mask positioning—both antithetical to the inherent instability of jet ablation. In sharp contrast, the 193-nm laser pulse produced relatively dim plasma flash but intense sodium emissions, rendering it ideal for analytical applications.

42

DWIVEDI, ASHUTOSH. "RECENT ADVANCES IN PULSED LASER ABLATED PLASMA PLUMES: A REVIEW." Surface Review and Letters 14, no. 01 (February 2007): 57–69. http://dx.doi.org/10.1142/s0218625x07009074.

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Pulsed laser ablation is a process in which an intense laser pulse interacts with the matter producing plasma. The present work describes the theoretical work being conducted in the past for the pulsed laser ablation phenomenon. It incorporates the theoretical models being proposed by various researchers around the globe for pulsed laser ablation. The main processes involved in the laser–matter interaction leading to plasma plume formation are the absorption and the reflection of the incident laser light by the condensed phase, ablation of the condensed phase, absorption of the laser light within the expanding plume, expansion of the vapor-plasma plume, and in the case of pulsed laser desorption, the interaction of the ablated species with the substrate surface. Thus the plasma, produced in the laser–matter interaction, plays an important role in the pulsed laser ablation (PLA) process.

43

Fiedler, V., F. Arnold, H. Schlager, and L. Pirjola. "Chinese SO<sub>2</sub> pollution over Europe – Part 2: Simulation of aerosol and cloud condensation nuclei formation." Atmospheric Chemistry and Physics Discussions 9, no. 1 (January 28, 2009): 2763–90. http://dx.doi.org/10.5194/acpd-9-2763-2009.

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Abstract. We report on sulfur dioxide (SO2) induced formation of aerosols and cloud condensation nuclei in an SO2 rich aged (9 days) pollution plume of Chinese origin, which we have detected at 5–7 km altitude during a research aircraft mission over the East Atlantic off the West coast of Ireland. Building on our measurements of SO2 and other trace gases along with plume trajectory simulations, we have performed model simulations of SO2 induced formation of gaseous sulfuric acid (GSA, H2SO4) followed by GSA induced formation and growth of aerosol particles. We find that efficient photochemical SO2 conversion to GSA took place in the plume followed by efficient formation and growth of H2SO4-H2O aerosol particles. Most particles reached sufficiently large sizes to act as cloud condensation nuclei whenever water vapor supersaturation exceeded 0.1–0.2%. As a consequence, smaller but more numerous cloud droplets are formed, which tend to increase the cloud albedo and to decrease the rainout efficiency. The detected plume represents an interesting example of the environmental impact of long range transport of fossil fuel combustion generated SO2.

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Sobecki, Christopher, Alfred Garrett, Brian d’Entremont, Ryan Connal, and Sebastian Aleman. "Assessment of Mechanical Draft Cooling Tower Thermal Emissions from Visual Images of Plumes." Atmosphere 14, no. 4 (April 21, 2023): 754. http://dx.doi.org/10.3390/atmos14040754.

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Using a one-dimensional code, we computed the power (enthalpy discharge rate) of a twelve-cell mechanical draft cooling tower (MDCT) using over two hundred visible condensed water vapor plume volume measurements derived from images, weather data, and tower operating conditions. The plume images were simultaneously captured by multiple stationary digital cameras surrounding the cooling tower. An analysis technique combining structure from motion (SfM), a neural-network-based image segmentation algorithm, and space carving was used to quantify the volumes. Afterwards, the power output was computed using novel techniques in the one-dimensional code that included cooling tower exhaust plume adjacency effects implemented with a modified version of the entrainment function, weather data averaged from eleven stations, and fan operations at the times when plume volumes were measured. The model was then compared with the averaged observed power output, and it validated well with an average error ranging from 6 to 12%, depending on the meteorological data used in the simulations. This methodology can possibly determine power plant fuel consumption rates by applying visible imagery.

45

Popel, S. I., and A. A. Gisko. "Charged dust and shock phenomena in the Solar System." Nonlinear Processes in Geophysics 13, no. 2 (June 21, 2006): 223–29. http://dx.doi.org/10.5194/npg-13-223-2006.

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Abstract. The results on shock phenomena in dusty plasmas of the Solar System are reviewed. The problems of dust ion acoustic bow shock in interaction of the solar wind with dusty cometary coma and formation of transient atmospheres of atmosphereless cosmic bodies such as Moon, Mercury, asteroids and comets are considered. The latter assumes the evolution of meteoroid impact plumes and production of charged dust grains due to the condensation of both the plume substance and the vapor thrown from the crater and the surrounding regolith layer. Physical phenomena occurring during large meteoroid impacts can be modeled with the aid of active rocket experiments, which involve the release of some gaseous substance in near-Earth space. New vistas in investigation of shock processes in natural dusty plasmas are determined.

46

Liang, Jian Jun, Yang Du, Yi Hong Ou, Xin Sheng Jiang, Hai Bing Qian, and Pei Wen Wang. "Experimental Visualization Study on the Explosion Process of Gasoline Vapor in Narrowly-Confined Space." Advanced Materials Research 791-793 (September 2013): 2108–11. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.2108.

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In this paper, experimental study on gasoline vapor explosion was conducted with data acquisition technology of high-speed camera. In the experiments, the flame behaviors and the flow field movements were shot by the high-speed camera, the space pressure were recorded by high-speed dynamic tester, and the explosion process were analyzed refinedly and intuitively. Studies have shown that according to variations of flame behaviors and pressure characteristics, process of gasoline vapor explosion can be divided into four stages: the ignition stage, the development stage, the intensification stage and the plume stage.

47

Xue, Boce, Baohua Chang, and Dong Du. "Monitoring of high-speed laser welding process based on vapor plume." Optics & Laser Technology 147 (March 2022): 107649. http://dx.doi.org/10.1016/j.optlastec.2021.107649.

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48

Duffey, T. P., T. G. McNeela, J. Mazumder, and A. L. Schawlow. "Absorption spectroscopic measurement of atomic density in laser‐induced vapor plume." Applied Physics Letters 63, no. 17 (October 25, 1993): 2339–41. http://dx.doi.org/10.1063/1.110519.

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49

Bykov, N. Yu. "Formation of Small Clusters in the Free Expanding Water Vapor Plume." Fluid Dynamics 53, no. 3 (May 2018): 428–37. http://dx.doi.org/10.1134/s0015462818030060.

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50

Davis, Sanford S. "An analytical model for a transient vapor plume on the Moon." Icarus 202, no. 2 (August 2009): 383–92. http://dx.doi.org/10.1016/j.icarus.2009.03.019.

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