Articles de revues : « Dust, analysis »

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Plumier, Benjamin M., Yumeng Zhao, Mark E. Casada, Ronaldo G. Maghirang et R. P. Kingsly Ambrose. « Analysis of Corn Dust Particle Properties and How Surface Roughness Influences Adhesion ». Transactions of the ASABE 63, n^o 5 (2020) : 1493–97. http://dx.doi.org/10.13031/trans.13892.

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HighlightsFreshly harvested, higher quality corn samples have a higher proportion of small dust particles with a lower circularity and aspect ratio compared to older, lower quality samples.For freshly harvested grain, dust particles removed at low centrifuge speed were significantly rougher than particles removed at high speed.Lower quality corn did not show a significant decrease in particle roughness for strongly attached dust.The surface area decreased while the surface energy increased with the attachment strength of dust particles.Abstract. High dust concentrations associated with grain handling can cause serious problems, including health and safety risks from dust inhalation and increased risk of explosions due to contained suspended dust in the presence of an ignition source. The amount of dust generated during grain handling is influenced by several factors, including the adhesion strength of dust to the grain. One factor that could influence the adhesion strength of grain dusts is how the dust particles are shaped and how their shape relates to the surface texture of corn. To better understand the properties of dust particles separated from corn samples, dust samples were analyzed for morphology and particle size. In addition, dust samples were separated with different centrifugation speeds to compare the properties of dusts that were strongly or weakly attached to the grain. These samples were observed with a light profilometer to measure their surface roughness characteristics. Results showed that freshly harvested corn samples contained a higher presence of small particles with low circularity than older, lower quality samples. The large particles observed were determined to be starch, as opposed to the smaller particles that were more likely soil or other non-plant-based material. The dust particles that were more strongly attached to corn kernels tended to have lower surface roughness than those that were weakly attached for the freshly harvested grain. Keywords: Dust adhesion, Particle shape, Surface adhesion, Surface roughness.

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Areias, Pedro, Jebun Naher Sikta et Manuel Pereira dos Santos. « Stable finite element analysis of viscous dusty plasma ». Engineering Computations 35, n^o 3 (8 mai 2018) : 1230–49. http://dx.doi.org/10.1108/ec-06-2017-0191.

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Purpose The purpose of this paper is to provide an analysis of dust acoustic (solitary) waves including viscosity. Specifically, the authors consider a dusty unmagnetized plasma system consisting of negatively charged dust and Boltzmann electrons and ions. Design/methodology/approach In this paper, a Petrov–Galerkin weak form with upwinding is adopted. Nonlinearity of ion and electron number density in terms of an electrostatic potential is included. A fully implicit time integration is used (backward Euler method), which requires the first derivative of the weak form. A three-field formulation is proposed, with the dust number density, the electrostatic potential and the dust velocity being the unknown fields. Findings In this study, two numerical examples are introduced and results show great promise for the proposed formulation as a predictive tool in viscous dusty plasmas. Presence of solitary waves was demonstrated. Dusty plasma vortices are predicted in 2D and 3D, as mentioned in the specialized literature. Research limitations/implications We observed some dependence on step size, which is due to the simple time-stepping scheme. This can be solved with a higher order integration scheme, which implies an added cost to the solution. Practical implications Dusty plasmas are found in astrophysics (Saturn rings) and electronics industry at several scales and have high impact as a contaminant. Originality/value To the authors’ knowledge, this is the first paper with a simulation of dusty plasma including vortices.

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Hu, Xiong, et Guang Sheng Ren. « Analysis of Dust in the Metro’s Bottom and the Dust Removal Project ». Advanced Materials Research 955-959 (juin 2014) : 3901–5. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.3901.

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After the metro run a long time, the bottom of the car body will be deposited amount of dusts. We must remove the dusts in the bottom. If we take some traditional methods, this not only will make the working environment dirty, but also unable to clear all dusts. This paper analyzes the dusts in the metro’s bottom first, and then introduces the dusts removal project, this project use 4 air compressors and 6 industrial vacuum cleaners, air compressors are on one side, and industrial vacuum cleaners are on the other side, this means we take two way to deduce the dust at the same time, blow and inhale. Last we design the vacuum pipelines.

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Havnes, Ove, Tarjei Antonsen, Gerd Baumgarten, Thomas W. Hartquist, Alexander Biebricher, Åshild Fredriksen, Martin Friedrich et Jonas Hedin. « A new method of inferring the size, number density, and charge of mesospheric dust from its in situ collection by the DUSTY probe ». Atmospheric Measurement Techniques 12, n^o 3 (15 mars 2019) : 1673–83. http://dx.doi.org/10.5194/amt-12-1673-2019.

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Abstract. We present a new method of analyzing measurements of mesospheric dust made with DUSTY rocket-borne Faraday cup probes. It can yield the variation in fundamental dust parameters through a mesospheric cloud with an altitude resolution down to 10 cm or less if plasma probes give the plasma density variations with similar height resolution. A DUSTY probe was the first probe that unambiguously detected charged dust and aerosol particles in the Earth's mesosphere. DUSTY excluded the ambient plasma by various biased grids, which however allowed dust particles with radii above a few nanometers to enter, and it measured the flux of charged dust particles. The flux measurements directly yielded the total ambient dust charge density. We extend the analysis of DUSTY data by using the impact currents on its main grid and the bottom plate as before, together with a dust charging model and a secondary charge production model, to allow the determination of fundamental parameters, such as dust radius, charge number, and total dust density. We demonstrate the utility of the new analysis technique by considering observations made with the DUSTY probes during the MAXIDUSTY rocket campaign in June–July 2016 and comparing the results with those of other instruments (lidar and photometer) also used in the campaign. In the present version we have used monodisperse dust size distributions.

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TRIBECHE, MOULOUD. « Small-amplitude analysis of a non-thermal variable charge dust soliton ». Journal of Plasma Physics 74, n^o 4 (août 2008) : 555–68. http://dx.doi.org/10.1017/s002237780800706x.

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AbstractSmall-amplitude electrostatic solitary waves are investigated in an unmagnetized dusty plasma with hot variable charge non-thermal dust grains. These nonlinear localized structures are small-amplitude self-consistent solutions of the Vlasov equation in which the dust response is non-Maxwellian. Localized solitary structures that may possibly occur are discussed and the dependence of their characteristics on physical parameters is traced. Our investigation may be taken as a prerequisite for the understanding of the electrostatic solitary waves that may occur in space dusty plasmas.

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Lin, Chang, Wei-gui Feng et Mai-mai Lin. « Theoretic study of dust acoustic waves in a dusty plasma with dust charge variation ». Communications in Nonlinear Science and Numerical Simulation 13, n^o 7 (septembre 2008) : 1287–93. http://dx.doi.org/10.1016/j.cnsns.2006.12.004.

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Cui, Yubao, Cuixiang Gao, Ying Zhou, Peng Zhou, Ming Peng, Yingzi Lin et Jianglong Peng. « Phylogenetic analysis of house dust mites ». Open Medicine 5, n^o 1 (1 février 2010) : 69–74. http://dx.doi.org/10.2478/s11536-009-0106-6.

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AbstractHouse dust mites live in house dusts and affect the health of humans. Among the many species, Dermatophagoides farinae, D. pteronyssinus, and Euroglyphus maynei have been found to be commonly associated with Ig-E-mediated allergic diseases. As a result, there is increasing effort to develop methods for the diagnosis and treatment of diseases caused by these species. The purpose of the current study was to explore the evolutionary relationships among house dust mites. After adult D. farinae were separated and isolated for total RNA extract, the cDNA coding for Der f 1 and Der f 2 were cloned and sequenced. Then amino acid sequences for group 1 and 2 allergens of two of the most common house dust mites, D. pteronyssinus, E. maynei, were obtained from databases. Interestingly, homological analysis of amino acid sequences showed that both Der p 1 and Der p 2 from D. pteronyssinus had more similarities to Eur m 1 and Eur m 2, respectively, than they had to Der f 1 and Der f 2 from D. farinae. In the phylogenetic trees, D. pteronyssinus clustered with E. maynei, but not with D. farinae, although D. pteronyssinus and D. farinae belong to the same genus according to morphological taxonomy. It was previously assumed that D. pteronyssinus was more similar to E. maynei than to D. farinae at evolutionary levels.

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Krawczyk, Janusz, Katarzyna Kocewiak, Jan Talaga et Irina Postnikova. « MECHANISMS OF TRAPPING FINE DUST IN WET DUST COLLECTING APPARATUS ». IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 62, n^o 9 (31 août 2019) : 97–101. http://dx.doi.org/10.6060/ivkkt.20196209.5926.

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The high efficiency of intensive operation of wet scrubbers is the result of a simultaneous formation of different mechanisms of dust particle collectors. The collectors can be understood as droplets of atomised liquid, bubbles formed in the conditions of intensive barbotage, liquid surface and wet surfaces. All collectors are formed during the operation of the circulating unit. The deposition of dust particles from gas occurs as a result of centrifugal forces and secondary circulations in the guide duct as well as the effect of the water curtain, liquid barbotage and the flow of dusty gas through the droplet-splash layer. Discussions substantiating the possibility of confirming the effect of suspension viscosity on the efficiency of the dust collection process can be related both to the analysis of basic mechanisms affecting the deposition of particles on liquid collectors and the conditions of generating collectors. In total liquid recirculation in wet dedusting equipment, concentration of solids in a liquid rises. In such conditions, a gradual decrease in their dedusting efficiency is possible. The effect depends on dust physiochemical properties, kinetic energy of particles, the type of equipment used, and specifically on the way of organization of the contact of the liquid and gas phases. Studies of the effectiveness of dedusting depending on various factors are given in the next article by the same authors.

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Li, Hui Xing, Bei Ni Li, Geng Geng, Wei Xiao et Wei Wang. « Detection and Analysis of Microbial Contamination in Central Air Conditioning System of a University ». Advanced Materials Research 610-613 (décembre 2012) : 661–64. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.661.

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Objective: Test the wind pipe dust and microorganism pollution status in the central air conditioning system of public buildings in the teaching area.Analysis of microbial pollution of the related factors.Methods:Sampling 6 functionally different area in the teaching building,using the microbiology analysis method on air conditioning system of blower tube surface dust pollution of microorganism detection,and the use of TiO2 photo catalyst purification mechanism on microbial contamination control.Results:on the basis of"centralized air ventilation system in public places sanitary specification",teaching areas of central air conditioning system of dust amount met the requirement basically.Bacterial concentrations generally beyond the standard,fungal concentration accords with the standard.The Method using TiO2 photo catalysis sterilization was proposed. Conclusion:Teaching of regional air conditioning pipe inner product dust weight is relatively large.Microbial pollution is serious.It is necessary that cleaning air conditioning system timely and using TiO2 Photocatalyst purification mechanism for killing air duct surface dust microorganism.

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Locard, Edmond. « Dust and its Analysis ». Police Journal : Theory, Practice and Principles 66, n^o 2 (avril 1993) : 153–65. http://dx.doi.org/10.1177/0032258x9306600208.

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Hlavay, József. « Analysis of respirable dust ». Microchemical Journal 46, n^o 1 (août 1992) : 121–29. http://dx.doi.org/10.1016/0026-265x(92)90028-2.

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Koeberl, Christian. « Analysis of interplanetary dust ». Geochimica et Cosmochimica Acta 58, n^o 23 (décembre 1994) : 5365. http://dx.doi.org/10.1016/0016-7037(94)90323-9.

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Abdullah, Manal Madhat, Mazin Al-Ansari et Rasha Ayad. « Analysis of repulsed dust from electrostatic curtain using different voltages ». Journal of Zankoy Sulaimani - Part A 17, n^o 1 (10 décembre 2014) : 1–6. http://dx.doi.org/10.17656/jzs.10355.

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Ki, Dae-Han, et Young-Dae Jung. « Size Effects on the Scattering of Electron and Spherical Dust Grain in Dusty Plasmas ». Zeitschrift für Naturforschung A 65, n^o 12 (1 décembre 2010) : 1147–50. http://dx.doi.org/10.1515/zna-2010-1221.

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The finite size effects of the charged dust grain on the electron-dust grain collisions are investigated in complex dusty plasmas. The stationary phase analysis and the effective potential due to the renormalized dust charge are employed to obtain the phase shift for the scattering of the electron and the spherically charged dust grain as a function of the impact parameter, collision energy, Debye length, and dust radius. It is found that the size effect of the dust grain enhances the electron-dust grain scattering cross section in dusty plasmas. It is also found that the size effect on the scattering cross section increases with increasing plasma density. In addition, it is found that the size effect on the electron-dust scattering cross section decreases with an increase of the plasma temperature.

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Jeong, G. Y., et E. P. Achterberg. « Chemistry and mineralogy of clay minerals in Asian and Saharan dusts and the implications for iron availability ». Atmospheric Chemistry and Physics Discussions 14, n^o 11 (17 juin 2014) : 15735–70. http://dx.doi.org/10.5194/acpd-14-15735-2014.

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Abstract. Mineral dust supplied to remote ocean regions stimulates phytoplankton growth through delivery of micronutrients, notably iron (Fe). Although attention is usually paid to Fe (hydr)oxides as major sources of available Fe, Fe-bearing clay minerals are typically the dominant phase in mineral dust. The mineralogy and chemistry of clay minerals in dust particles, however, are largely unknown. We conducted microscopic identification and chemical analysis of the clay minerals in Asian and Saharan dust particles. Cross-sectional slices of dust particles were prepared by focused ion beam (FIB) techniques and analyzed by transmission electron microscopy (TEM) combined with energy dispersive X-ray spectroscopy (EDXS). TEM images of FIB slices revealed that clay minerals occurred as either nano-thin platelets or relatively thick plates. The nano-thin platelets included illite, smectite, illite–smectite mixed layers and their nanoscale mixtures (illite–smectite series clay minerals, ISCMs) which could not be resolved with an electron microbeam. EDXS chemical analysis of the clay mineral grains revealed that the average Fe content was 5.8% in nano-thin ISCM platelets assuming 14% H2O, while the Fe content of illite and chlorite was 2.8 and 14.8%, respectively. In addition, TEM and EDXS analyses were performed on clay mineral grains dispersed and loaded on microgrids. The average Fe content of clay mineral grains was 6.7 and 5.4% in Asian and Saharan dusts, respectively. A comparative X-ray diffraction analysis of bulk dusts showed that Saharan dust was more enriched in clay minerals than in Asian dust, while Asian dust was more enriched in chlorite. The average Fe / Si, Al / Si and Fe / Al molar ratios of the clay minerals, compared to previously reported chemistries of mineral dusts and leached solutions, indicated that dissolved Fe originated from clay minerals. Clay minerals, in particular nanocrystalline ISCMs and Fe-rich chlorite are important sources of available Fe in remote marine ecosystems. Further detailed analyses of the mineralogy and chemistry of clay minerals in global aerosols are required to determine the inputs of Fe available to surface ocean microbial communities.

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Jeong, G. Y., et E. P. Achterberg. « Chemistry and mineralogy of clay minerals in Asian and Saharan dusts and the implications for iron supply to the oceans ». Atmospheric Chemistry and Physics 14, n^o 22 (27 novembre 2014) : 12415–28. http://dx.doi.org/10.5194/acp-14-12415-2014.

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Abstract. Mineral dust supplied to remote ocean regions stimulates phytoplankton growth through delivery of micronutrients, notably iron (Fe). Although attention is usually paid to Fe (hydr)oxides as major sources of available Fe, Fe-bearing clay minerals are typically the dominant phase in mineral dust. The mineralogy and chemistry of clay minerals in dust particles, however, are largely unknown. We conducted microscopic identification and chemical analysis of the clay minerals in Asian and Saharan dust particles. Cross-sectional slices of dust particles were prepared by focused ion beam (FIB) techniques and analyzed by transmission electron microscopy (TEM) combined with energy dispersive X-ray spectroscopy (EDXS). TEM images of FIB slices revealed that clay minerals occurred as either nano-thin platelets or relatively thick plates. Chemical compositions and lattice fringes of the nano-thin platelets suggested that they included illite, smectite, illite–smectite mixed layers, and their nanoscale mixtures (illite–smectite series clay minerals, ISCMs) which could not be resolved with an electron microbeam. EDXS chemical analysis of the clay mineral grains revealed that the average Fe content was 5.8% in nano-thin ISCM platelets assuming 14% H2O, while the Fe content of illite and chlorite was 2.8 and 14.8%, respectively. In addition, TEM and EDXS analyses were performed on clay mineral grains dispersed and loaded on micro-grids. The average Fe content of clay mineral grains was 6.7 and 5.4% in Asian and Saharan dusts, respectively. A comparative X-ray diffraction analysis of bulk dusts showed that Saharan dust was more enriched in clay minerals than Asian dust, while Asian dust was more enriched in chlorite. Clay minerals, in particular nanocrystalline ISCMs and Fe-rich chlorite, are probably important sources of Fe to remote marine ecosystems. Further detailed analyses of the mineralogy and chemistry of clay minerals in global mineral dusts are required to evaluate the inputs of Fe to surface ocean microbial communities.

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Lin, Chang, et Mai-mai Lin. « Study of the dust acoustic waves in a magnetized dusty plasma with many different dust grains ». Communications in Nonlinear Science and Numerical Simulation 15, n^o 4 (avril 2010) : 852–56. http://dx.doi.org/10.1016/j.cnsns.2009.05.012.

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Kaur, Daljeet, Suresh C. Sharma, R. S. Pandey et Ruby Gupta. « Weibel instability oscillation in a dusty plasma with counter-streaming electrons ». Laser and Particle Beams 38, n^o 1 (17 janvier 2020) : 8–13. http://dx.doi.org/10.1017/s0263034619000776.

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AbstractWe investigate the Weibel instability (WI) in a dusty plasma which is driven to oscillation by the addition of dust grains in the plasma. Our analysis predicts the existence of three modes in a dusty plasma. There is a high-frequency electromagnetic mode, whose frequency increases with an increase in the relative number density of dust grains and which approaches instability due to the presence of dust grains. The second mode is a damping mode which exists due to dust charge fluctuations in plasma. The third mode is the oscillating WI mode. The dispersion relation and the growth rate of various modes in the dusty plasma are derived using the first-order perturbation theory. The effect of dust grain parameters on frequency and growth rate is also studied and reported.

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Abdul Rauf, I. Zeba et Muhammad Saqlain. « Modified Dust-Lower-Hybrid Waves in Quantum Plasma ». Scientific Inquiry and Review 2, n^o 2 (30 avril 2018) : 11–21. http://dx.doi.org/10.32350/22/020202.

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Dust-lower-hybrid waves in quantum plasma have been studied. The dispersion relation of the dust-lower-hybrid wave has been examined using the quantum hydrodynamic model of plasma in an ultra-cold Fermi dusty plasma in the presence of a uniform external magnetic field. Graphical analysis shows that the electron Fermi temperature effect and the quantum corrections give rise to significant effects on the dust-lower-hybrid wave of the magnetized quantum dusty plasma.

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Reichel, M., S. Staiger et S. Biselli. « Analysis of Fusarium toxins in grain via dust : a promising field of application for rapid test systems ». World Mycotoxin Journal 7, n^o 4 (1 janvier 2014) : 465–77. http://dx.doi.org/10.3920/wmj2013.1687.

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On site, mycotoxin measurements shall enable rapid decisions on the acceptance or rejection of lots. Hence, results have to be available fast, easy to get and, first of all, reliable. An innovative approach using dust samples was tested for its fitness for on-site mycotoxin analyses of grain lots and compared to current practice in grain testing. To prove correlation between mycotoxin concentrations in dust and respective concentrations in grain, regression analyses were performed. To obtain data points, dust was sieved from grain and both samples were analysed. As the contamination of the overall sample and its dust particles correlated well (wheat: R2DON=0.85, R2ZEA=0.82; rye: R2DON=0.73), contaminations in the grain were predictable from concentrations determined in respective dust particles. For on-site analysis, common lateral flow devices (LFD) were evaluated for their suitability to detect deoxynivalenol (DON) in grain dusts. On site, grain and dust samples were taken during the unloading of trucks using a customised dust-sampler. In contrast to grain samples, no additional physical sample preparation or homogenisation step was needed for dust. Instead, the sample was directly extracted and analysed for DON using LFD. By means of the regression line DON concentrations in grain were predicted from dust results and compared to concentrations directly measured in grain samples. No false negative results were observed and a contaminated grain lot (<1000 ?g/ kg DON) could be clearly identified. Evidence for reduced measurement uncertainty compared to current practice at lower total measurement costs was given. In this way, the fitness for purpose of the new approach combining rapid analyses with dust sampling for on-site mycotoxin screening was shown. The innovative high-throughput technology has the potential to improve on-site mycotoxin measurements in terms of speed, sensitivity, manageability and reliability and thus is a promising tool for enhanced industrial self-control.

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Gu, Z. L., J. Qiu, Y. Z. Zhao et X. P. Hou. « Analysis on Dust Devil Containing Loess Dusts of Different Sizes ». Aerosol and Air Quality Research 8, n^o 1 (2008) : 65–77. http://dx.doi.org/10.4209/aaqr.2007.03.0026.

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Alotaibi, B. M., Haifa A. Al-Yousef, R. E. Tolba et W. M. Moslem. « Nonlinear dust-acoustic modes in homogeneous dusty plasmas : bifurcation analysis ». Physica Scripta 96, n^o 12 (16 septembre 2021) : 125611. http://dx.doi.org/10.1088/1402-4896/ac2183.

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Contini, Marcella. « Analysis of dust through extinction ». Astrophysics and Space Science 198, n^o 1 (1992) : 29–51. http://dx.doi.org/10.1007/bf00644298.

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Nomura, S., et T. Tanaka. « Theoretical analysis of dust explosions ». Powder Technology 71, n^o 2 (août 1992) : 189–96. http://dx.doi.org/10.1016/0032-5910(92)80008-k.

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Bruni, Marco, et Kamilla Piotrkowska. « Dust–radiation universes : stability analysis ». Monthly Notices of the Royal Astronomical Society 270, n^o 3 (octobre 1994) : 630–40. http://dx.doi.org/10.1093/mnras/270.3.630.

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Britton, Laurence G., et David C. Kirby. « Analysis of a dust deflagration ». Plant/Operations Progress 8, n^o 3 (juillet 1989) : 177–80. http://dx.doi.org/10.1002/prsb.720080312.

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Fan, Wei, et Guo Jun Ma. « XPS Analysis of Stainless Steel Plant Dust ». Advanced Materials Research 634-638 (janvier 2013) : 3159–62. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.3159.

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Due to the fact that it contains several kinds of toxic substances, stainless steel plant dust is regarded as a toxic solid waste. In this paper, XPS technique was employed to determine the elemental depth profiles on the surface of dust, especially Cr, in order to provide useful information on Cr(VI) formation mechanisms as well as the distribution of other element on the surface of stainless steel plant dust. The results showed that without sputtering with Ar ion beam, both Cr(VI) and Cr(III) exist on the surface of the dust. Cr(VI) mainly exists on the surface of the dust in the form of CrO3. When the sputtering time is from 0s to 80s, the substances exist on the surface of EAF dust are Cr2O3 and CrO3, and at the rest of the sputtering time, Cr2O3 is the only chromium-bearing substance existing on the surface of dust. When the sputtering time is from 0s to 80s, the substances exist on the surface of AOD dust are the same as the EAF dust. But at the rest of the sputtering time, Cr2O3 or FeCr2O4 are the chromium-bearing species.

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Gong, Xiaoyan, Congcong Jia, Kang Sun, Jian Cui, Kefan Lei, Yuxuan Xue et He Xue. « Distribution Law and Prediction Model of Dust Concentration under Airflow Adjustment in Fully Mechanized Heading Face ». Mathematical Problems in Engineering 2019 (21 juillet 2019) : 1–17. http://dx.doi.org/10.1155/2019/6210704.

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The current situation of extensive ventilation management for the fully mechanized heading face cannot dynamically control air velocity and make reasonable dust migration distribution, resulting in serious disaster of dust and environmental pollution in the roadway. In this paper, the fluid mechanics, finite element numerical simulation, and underground measurement were combined to analyze the distribution of dust concentration under the variable airflow state at the duct outlet to obtain the massive correlation data of duct outlet parameters and dust concentration. For the pedestrian breathing-height in the backflow side and driver location, the double-objective BP prediction model for dust concentration under airflow adjustment was established, and the performance parameters and prediction accuracy of the BP prediction model were analyzed by using the relative error and fitting analysis. In Ningtiaota coal mine, located in Northern Shaanxi province of China, the self-developed control device is installed on the duct outlet with underground test and application verification to refine the model. The results indicated the dynamic control of airflow optimizes dust concentration distribution. The dust concentration at the pedestrian breathing-height in the backflow side and driver location was significantly decreased after the installation of adjustment device. Dust concentration at the pedestrian breathing-height and driver location was decreased by 31% and 34%, respectively, compared with the results before adjustment, which achieved the safe, environment-friendly, and energy-saving ventilation and the dust removal function in fully mechanized heading face.

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Pitak, Inna, Serhii Briankin, Oleg Pitak et Valery Shaporev. « ANALYSIS OF THE SANITARY PURIFICATION OF GAS EMISSIONS FROM DUST IN THE LIME MANUFACTURE ». EUREKA : Physics and Engineering 5 (29 septembre 2017) : 65–72. http://dx.doi.org/10.21303/2461-4262.2017.00435.

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Experimental studies have been carried out to study the effect of the location of the blade vortex from the end of the flue (the flow outflow from the flue to the separation chamber) by the value Vjmax and the determination of the optimum cross section where Vjmax is reached, and also the study of the influence of structural changes on the purification efficiency. The dependence of this swirler on the value of the tangential velocity of the gas flow at its exit from the separator is established. The cross-sections of the flue duct in which, after the swirler, the maximum values Vj, Vr are reached, the features of the dust-gas flow in the studied sections are considered. Based on the studies of the hydrodynamic situation during the flow of a rotating flow in the flue after the swirler, the possibilities of agglomeration of dust particles in the investigated zones, as well as the destruction of NOx gas impurities, are analyzed. During the operation of the reconstructed vortex dust collector, qualitative indices are attained, which confirm the expediency of the conducted studies and the expediency of reconstructing the vortex apparatus. It is proved that the installation of the blade vortex enhances the purification efficiency of the dust-gas flow in a vortex dust collector and will allow for a comprehensive purification of the exhaust gases.

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Papkova, A., S. Papkov et D. Shukalo. « Modelling the generation of dusty marine aerosol by expeditionary data and remote sensing methods over the Black Sea region ». E3S Web of Conferences 224 (2020) : 02031. http://dx.doi.org/10.1051/e3sconf/202022402031.

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During a long-range transport, Sahara dust is naturally mixed with other aerosols, including maritime. At present, the mixing of these types of marine and dust aerosols is of particular interest, since it is important to correctly estimate the ionic and mass balance of aerosol particles. This problem is caused by the need for a reliable determination of the aerosol source and for correct atmospheric correction of satellite data. An analysis was made of the correlation between the change in the AOT parameter and the dates of dust transport from the Sahara to the Black Sea region. The analysis results confirmed the fact that the presence of dust aerosol over the Black Sea water area has a strong effect on the AOT indicator at all wavelengths, increasing the parameter almost by 2 times. This fact is correspondent to the generation of a secondary type of aerosol, namely, dusty marine aerosol. Analysis of CALIPSO aerosol subtype maps also revealed the presence of dusty marine aerosol with corresponding depolarization coefficients.

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Ganzha, Dmytro, et Ryta Ganzha. « Dusty atmospheric sediments of cold season of the year in Ivano-Frankivsk region ». Visnyk of the Lviv University. Series Geography, n^o 47 (23 novembre 2014) : 68–77. http://dx.doi.org/10.30970/vgg.2014.47.818.

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Physical properties of dusty sediment on snow cover in the Forecarpathian region were studied. Analysis of the suspension of atmospheric dust in melted snow was conducted by nephelometry method. The evaluation of the properties of the dust was carried out by the sedimentation dynamics of the particles of suspension in melted snow. The data were processed by methods of correlation, regression, variance, ecological and geochemical analyses. It was established that 12 % of surveyed area are in a regional natural background, more than a third is in a man-made pollution, a half is in a manmade background. Key words: atmospheric air dust, environmental monitoring, observation of snow, man-made pollution.

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Al-Hamouz, Zakariya, et Amer El-Hamouz. « Analysis of a wire–duct electrostatic precipitator under dust loading conditions ». Energy Conversion and Management 52, n^o 2 (février 2011) : 1235–43. http://dx.doi.org/10.1016/j.enconman.2010.09.019.

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Reddy, Prof Kamal, et Prof Avinash Reddy. « Balance Analysis Of Dust Over Onus Backfill Structure Victimization Physical Create Skill ». American Journal of Applied Sciences 01, n^o 05 (1 décembre 2019) : 11–16. http://dx.doi.org/10.37547/tajas/volume01issue05-02.

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Aili, Aishajiang, Hailiang Xu, Tursun Kasim et Abudumijiti Abulikemu. « Origin and Transport Pathway of Dust Storm and Its Contribution to Particulate Air Pollution in Northeast Edge of Taklimakan Desert, China ». Atmosphere 12, n^o 1 (14 janvier 2021) : 113. http://dx.doi.org/10.3390/atmos12010113.

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The Taklimakan Desert in Northwest China is the major source of dust storms in China. The northeast edge of this desert is a typical arid area which houses a fragile oasis eco-environment. Frequent dust storms cause harmful effects on the oasis ecosystem and negative impacts on agriculture, transportation, and human health. In this study, the major source region, transport pathway, and the potential contribution of dust storms to particulate air pollution were identified by using both trajectory analysis and monitoring data. To assess the source regions of dust storms, 48 h backward trajectories of air masses arriving at the Bugur (Luntai) County, which is located at the northeast edge of Taklimakan Desert, China on the dusty season (spring) and non-dusty month (August, representing non-dusty season) in the period of 1999–2013, were determined using Hybrid Single Particle Lagrangian Integrated Trajectory model version 4 (HYSPLIT 4). The trajectories were categorized by k-means clustering into 5 clusters (1a–5a) in the dusty season and 2 clusters (1b and 2b) in the non-dusty season, which show distinct features in terms of the trajectory origins and the entry direction to the site. Daily levels of three air pollutants measured at a station located in Bugur County were analyzed by using Potential Source Contribution Function (PSCF) for each air mass cluster in dusty season. The results showed that TSP is the major pollutant, with an average concentration of 612 µg/m3, as compared to SO2 (23 µg/m3) and NO2 (32 µg/m3) in the dusty season. All pollutants were increased with the dust weather intensity, i.e., from suspended dust to dust storms. High levels of SO2 and NO2 were mostly associated with cluster 1a and cluster 5a which had trajectories passing over the anthropogenic source regions, while high TSP was mainly observed in cluster 4a, which has a longer pathway over the shifting sand desert area. Thus, on strong dust storm days, not only higher TSP but also higher SO2 and NO2 levels were observed as compared to normal days. The results of this study could be useful to forecast the potential occurrence of dust storms based on meteorological data. Research focusing on this dust-storm-prone region will help to understand the possible causes for the changes in the dust storm frequency and intensity, which can provide the basis for mitigation of the negative effects on human health and the environment.

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Millette, J. R., P. Few et T. J. Hopen. « Microscopical Examination of Indoor Dusts ». Microscopy and Microanalysis 4, S2 (juillet 1998) : 476–77. http://dx.doi.org/10.1017/s1431927600022509.

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Several case studies are shown as examples of the results of analyses using various microscopical instruments to characterize the particles in building dusts. Characterizing the particles and identifying possible sources of particles in dusts are often important parts of solving indoor indoor air quality (IAQ) and environmental problems. Samples of the dust particles can be collected by filtering the air with cassette air filters or by gathering the dust that has accumulated on surfaces. Depending on the size and types of particles in the dust either polarized light microscopy (PLM), scanning electron microscopy with x-ray analysis (SEM/EDS), analytical transmission electron microscopy (ATEM) or Fourier transform infrared microspectroscopy (FTIR) may be used solely or in combination. PLM can characterize most of the common dust particle in residential and commercial buildings. SEM/EDS is helpful in identifying metal particles and when used in the backscatter electron mode, a large number of particles can be surveyed and those containing heavy metals such as lead and cadmium can be identified quickly.

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ROSENBERG, M., et V. W. CHOW. « Collisional effects on the electrostatic dust cyclotron instability ». Journal of Plasma Physics 61, n^o 1 (janvier 1999) : 51–63. http://dx.doi.org/10.1017/s0022377898007247.

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A kinetic analysis of the electrostatic dust cyclotron instability in a weakly ionized collisional dusty plasma is presented. In a plasma with negatively charged dust and a current along the magnetic field B, it is found that the instability can be excited by ions drifting along B. The effect of dust–neutral collisions is stabilizing, while the effect of ion–neutral collisions can be destabilizing. Possible applications to laboratory environments are discussed.

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Huang, Xu. « Air Curtain Dust Removal Device Design and Dust Prevention Strategy in Heading Face ». Advances in Civil Engineering 2020 (12 octobre 2020) : 1–8. http://dx.doi.org/10.1155/2020/8891599.

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Dust protection is a safety guarantee of heading face. The previous model of air curtain research was ideal, and the dust removal effect was rarely studied in the actual dust-producing face. This paper presents a method of air curtain dust removal (ACDR) in the actual heading face. The author designed an air curtain dust removal device (ACDRD). The law of total dust concentration, respiratory dust concentration, and respiratory dust ratio is obtained. The minimum outlet airflow velocity is analyzed using the flat-plane injection theory. The effect of the exhaust fan placement on the dust removal effectiveness is examined. Research indicates the following: The airflow speed at the upper, left, and right sides of the ∩-shaped slot is 17.39 m/s, 12.04 m/s, and 13.66 m/s, respectively. The minimum dust removal speed of the air curtain is 5.48 m/s. The total dust concentration is the highest in the spot of roadheader operator, and the concentration of respiratory dust decreases sharply within 20 m. When the indentation air duct is 2.1 m away from the base plate, the dust-proof effect is better. The results can provide theoretical bases and methods for air curtain analysis of the heading face.

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Stuper-Szablewska, Kinga, Tomasz Rogoziński et Juliusz Perkowski. « Contamination of pine and birch wood dust with microscopic fungi and determination of its sterol contents ». Archives of Industrial Hygiene and Toxicology 68, n^o 2 (27 juin 2017) : 127–34. http://dx.doi.org/10.1515/aiht-2017-68-2924.

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Abstract Wood compounds, especially sterols, are connected with the level of contamination with microscopic fungi. Within this study, tests were conducted on wood dust samples collected at various work stations in a pine and birch timber conversion plant. Their contamination with mycobiota was measured as the concentration of ergosterol (ERG) by ultra performance liquid chromatography (UPLC). Another aim of this study was to assess the effect of contamination with microscopic fungi on the sterol contents in wood dusts. Analyses were conducted on five sterols: desmosterol, cholesterol, lanosterol, stigmasterol, and β-sitosterol using UPLC and their presence was confirmed using gas chromatography/mass spectrometry (GC/MS). The results of chemical analyses showed the greatest contamination with mycobiota in birch wood dust. We also observed varied contents of individual sterols depending on the wood dust type. Their highest concentration was detected in birch dust. The discriminant analysis covering all tested compounds as predictors showed complete separation of all tested wood dust types. The greatest discriminatory power was found for stigmasterol, desmosterol, and ergosterol.

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Córdoba-Jabonero, C., M. Sorribas, J. L. Guerrero-Rascado, J. A. Adame, Y. Hernández, H. Lyamani, V. Cachorro et al. « Synergetic monitoring of Saharan dust plumes and potential impact on surface : a case study of dust transport from Canary Islands to Iberian Peninsula ». Atmospheric Chemistry and Physics Discussions 10, n^o 11 (9 novembre 2010) : 27015–74. http://dx.doi.org/10.5194/acpd-10-27015-2010.

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Abstract. Synergetic use of meteorological information, remote sensing both ground-based active (lidar) and passive (sun-photometry) techniques together with backtrajectory analysis and in situ measurements is carried out for the characterization of dust intrusions. A case study of air masses advected from Saharan region to the Canary Islands and the Iberian Peninsula, relatively located close and far away from the dust sources, respectively, was monitored from 11 to 19 March 2008. The observations were performed over three Spanish geographically strategic within the dust-influenced area stations along a common dust plume pathway. A 4-day long dust event (13–16 March) over the Santa Cruz de Tenerife Observatory (SCO), and a linked short 1-day dust episode (14 March) in the Southern Iberian Peninsula over both the Atmospheric Sounding Station "El Arenosillo" (ARN) and the Granada station (GRA) were detected. Meteorological situation favoured the dust plume transport over the area under study. Backtrajectory analysis clearly showed the Saharan origin of the dust intrusion. Under the Saharan air masses influence, AERONET Aerosol Optical Depth at 500 nm (AOD500) ranged from 0.3 to 0.6 and Angstrom Exponent at 440/675 nm wavelength pair (AE440/675) was lower than 0.5, indicating a high loading and predominance of coarse particles during those dusty events. Lidar observations characterized their vertical layering structure, identifying different aerosol contributions depending on altitude. In particular, the 3-km height layer observed over ARN and GRA stations corresponds to that dust plume transported from Saharan region after crossing through Canary Islands at 3 km height as observed over SCO site as well. No significant differences were found in the lidar (extinction-to-backscatter) ratio (LR) estimation for that dust plume over all stations when a suitable aerosol scenario for lidar data retrieval is selected. Lidar-retrieved LR values of 65–70 sr were obtained during the principal dusty episodes. These similar LR values found in all the stations suggest that dust properties were kept unchanged in the course of its medium-range transport. In addition, the potential impact on surface of that Saharan dust intrusion over the Iberian Peninsula was evaluated by ground-level in situ measurements for particle deposition assessment together with backtrajectory analysis. However, no connection between those dust plumes and the particle sedimentation registered at ground level is found. Differences on particle deposition process observed in both Southern Iberian Peninsula sites are due to the particular dust transport pattern occurred in each station.

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Liu, Z., D. Liu, J. Huang, M. Vaughan, I. Uno, N. Sugimoto, C. Kittaka et al. « Airborne dust distributions over the Tibetan Plateau and surrounding areas derived from the first year of CALIPSO lidar observations ». Atmospheric Chemistry and Physics 8, n^o 16 (29 août 2008) : 5045–60. http://dx.doi.org/10.5194/acp-8-5045-2008.

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Abstract. Using an analysis of the first full year of CALIPSO lidar measurements, this paper derives unprecedented, altitude-resolved seasonal distributions of desert dust transported over the Tibetan Plateau (TP) and the surrounding areas. The CALIPSO lidar observations include numerous large dust plumes over the northern slope and eastern part of the TP, with the largest number of dust events occurring in the spring of 2007, and some layers being lofted to altitudes of 11–12 km. Generation of the Tibetan airborne dusts appears to be largely associated with source regions to the north and on the eastern part of the plateau. Examination of the CALIPSO time history reveals an "airborne dust corridor" due to the eastward transport of dusts originating primarily in these source areas. This corridor extends from west to east and shows a seasonality largely modulated by the TP through its dynamical and thermal forcing on the atmospheric flows. On the southern side, desert dust particles originate predominately in Northwest India and Pakistan. The dust transport occurs primarily in dry seasons around the TP western and southern slopes and dust particles become mixed with local polluted aerosols. No significant amount of dust appears to be transported over the Himalayas. Extensive forward trajectory simulations are also conducted to confirm the dust transport pattern from the nearby sources observed by the CALIPSO lidar. Comparisons with the OMI and MODIS measurements show the unique capability of the CALIPSO lidar to provide unambiguous, altitude-resolved dust measurements.

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Vaughan, M., C. Trepte, C. Hostetler et D. Winker. « Airborne dust distributions over the Tibetan Plateau and surrounding areas derived from the first year of CALIPSO lidar observations ». Atmospheric Chemistry and Physics Discussions 8, n^o 2 (25 mars 2008) : 5957–77. http://dx.doi.org/10.5194/acpd-8-5957-2008.

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Abstract. Airborne dust is a major environmental hazard in Asia. Using an analysis of the first full year of CALIPSO lidar measurements, this paper derives unprecedented, altitude-resolved seasonal distributions of desert dust transported over the Tibetan Plateau (TP) and the surrounding areas. The CALIPSO lidar observations include numerous large dust plumes over the northern slope and eastern part of the TP, with the largest number of dust events occurring in the spring of 2007, and some layers being lofted to altitudes of 10 km and higher. Generation of the Tibetan airborne dusts appears to be largely associated with source regions to the north and on the eastern part of the plateau. Examination of the CALIPSO time history reveals an "airborne dust corridor" due to the eastward transport of dusts originating primarily in these source areas. This corridor extends from west to east and shows a seasonality largely modulated by the TP through its dynamical and thermal forcing on the atmospheric flows. On the southern side, desert dust particles originate predominately in North India and Pakistan. The dust transport occurs primarily in dry seasons around the TP western and southern slopes and dust particles become mixed with local polluted aerosols. No significant amount of dust appears to be transported over the Himalayas. Extensive forward trajectory simulations are also conducted to confirm the dust transport pattern from the nearby sources observed by the CALIPSO lidar.

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Xiao, Jun, Juan Huang, Yao-dong Jiang, Cao Chong, Lei Zhang et Xue Zhang. « Comparison Analysis of Dust-Depressor Using Microbial Induced Carbonate Precipitation with Urease Reagent ». Sustainability in Environment 2, n^o 4 (29 novembre 2017) : 379. http://dx.doi.org/10.22158/se.v2n4p379.

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The dust-depressors have been developed utilizing a method of microbial induced carbonate precipitation. This microbial dust-depressor has the characteristics of high efficiency for dust suppression and environmental protection. Optimal compositions of urease dust-depressor and microbial dust-depressor have been studied. In addition, pure water, CaCl2 and super absorbent polymer are chosen to compare with new dust-depressors on the performances. The results showed that the microbial dust-depressor had 3.13 mm/min of seepage velocity and 79.1% of dust suppression efficiency, which were superior to other dust-depressors on the performance of seepage velocity and dust suppression efficiency.

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Dorriné, W., P. Van Espen, F. Adams et B. Préat. « Characterisation and Classification of Individual Coal Mine Dust Particles by Computer-Controlled Electron Microprobe Analysis ». Proceedings, annual meeting, Electron Microscopy Society of America 48, n^o 2 (12 août 1990) : 294–95. http://dx.doi.org/10.1017/s0424820100135071.

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Extremely dusty working conditions are a serious health risk for coal miners. Quartz and other minerals are known to cause lung diseases when inhaled over long periods of time. In this work, a study was made of the mineral content in coal mine dust. Individual particles were characterised using computer controlled electron microprobe analysis and then classified into different mineral categories using a multivariate classification procedure.Coal mine dust particles were collected from the Zolder coal mine, Belgium, using a BAT II cyclone sampling unit. Small quantities of the dust were suspended in n-hexane using an ultrasonic water bath. Approximately 100 μl of the suspension were spotted on a plexiglass stub and dried. The excess carbon was removed by ashing the samples for two hours in a low temperature asher (LTA). The samples were coated with a carbon layer of ±40 nm for microprobe analysis. An identical sample preparation procedure was used to prepare 6 mineral standards : biotite, illite, kaolinite, quartz, muscovite and ripidolite.

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MAMUN, A. A. « A new electrostatic mode in a dusty plasma due to dust charge fluctuation ». Journal of Plasma Physics 75, n^o 3 (juin 2009) : 389–93. http://dx.doi.org/10.1017/s0022377808007629.

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AbstractA dusty plasma consisting of cold and hot electrons, cold ions, and charge fluctuating isolated cold dust has been considered. It has been shown by a normal mode analysis that in such a dusty plasma there exists a new type of electrostatic perturbation mode due to the charge fluctuation of the isolated dust. The basic features of this new electrostatic perturbation mode, which are different from those of the electron-acoustic waves, have also been analytically identified. The implications of these results in both the space and laboratory dusty plasma conditions are briefly discussed.

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Wang, Zi, Yu Dong Yang, Jing Liu, Xiao Ping Qu et Yan Yang Zhou. « Fault Analysis of a Dust-Removing Blower in a Sintering Plant Based on Envelope Analysis ». Applied Mechanics and Materials 779 (juillet 2015) : 145–50. http://dx.doi.org/10.4028/www.scientific.net/amm.779.145.

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Dust-removing blower is a key equipment in sintering plants, which can provide enough wind and negative pressure. It can also improve the efficiency of dust-removing. The vibration level of a dust-removing blower in a sintering plant is very high, which is beyond its normal value. Due to the complex working condition and strong background noise, it is difficult to extract fault features from the vibration signal of the dust-removing blower. Therefore, fault analysis of the blower is very difficult. Since the modulation phenomenon existed in the vibration signal of the blower is found, the envelope analysis based on the Hilbert transform is proposed to demodulate the vibration signal. The frequency spectrum of the demodulated signal shows that the first order frequency characteristic is obvious, which can effectively reveal the dynamic unbalance of the rotor system is the main reason of the abnormal vibration of the blower. According to this diagnosis, some possible reasons for the unbalance are proposed, as well as advices regarding to the repair of the blower system. Moreover, the test and analysis are conducted on the repaired blower system. The results show that the unbalance problem is eliminated and the blower can work normally, which can validate the accuracy and reliability of the proposed diagnosis method for fault analysis of the dust-removing blower.Keywords: dynamic unbalance; modulation; dust-removing blower; Hilbert Transform

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Ivanova, A. R., E. N. Skriptunova, N. I. Komasko et A. A. Zavialova. « Dust storm episodes at the aerodromes in the Asian part of Russia ». Hydrometeorological research and forecasting 2 (23 juin 2021) : 20–42. http://dx.doi.org/10.37162/2618-9631-2021-2-20-42.

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Dust storm episodes at the aerodromes in the Asian part of Russia / Ivanova A.R., Skriptunova E.N., Komasko N.I., Zavialova A.A.// Hydrometeorological Research and Forecasting, 2021, no. 2 (380), pp. 20-42. According to 2001-2020 METAR data, episodes of dust storms at 26 international aerodromes in the Asian Russia causing poor visibility are studied. The conditions for issuing reports on dust storms, their correspondence to the definition of a dust storm are discussed. It was found that out of 337 reports describing dust transport by strong wind, only 7 episodes registered at the aerodromes of Irkutsk, Abakan, Omsk, and Blagoveshchensk corresponded to the classical definition. The others detected at 15 of 26 aerodromes may be defined as “dust events” – the episodes of dust transfer causing the nonessential visibility reduction. The seasonal variation in such episodes and its connection with changes in visibility are studied. The characteristics of dusty air masses and the direction of their advection are given. Keywords: dust storm, dust events, aerodromes of Asian Russia, seasonal variation, trajectory analysis

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Yu, Yan, Olga V. Kalashnikova, Michael J. Garay, Huikyo Lee, Myungje Choi, Gregory S. Okin, John E. Yorks, James R. Campbell et Jared Marquis. « A global analysis of diurnal variability in dust and dust mixture using CATS observations ». Atmospheric Chemistry and Physics 21, n^o 3 (3 février 2021) : 1427–47. http://dx.doi.org/10.5194/acp-21-1427-2021.

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Abstract. The current study investigates the diurnal cycle of dust and dust mixture loading across the global tropics, subtropics, and mid-latitudes by analyzing aerosol extinction and typing profiles observed by the Cloud-Aerosol Transport System (CATS) lidar aboard the International Space Station. According to the comparison with ground-based and other satellite observations, CATS aerosol and dust and dust mixture loading observations exhibit reasonable quality but significant day–night inconsistency. To account for this day–night inconsistency in CATS data quality, the diurnal variability in dust and dust mixture characteristics is currently examined separately for daytime and nighttime periods. Based on an analysis of variance (ANOVA) analytical framework, pronounced diurnal variations in dust and dust mixture loading are generally uncovered during daytime periods and over terrestrial areas. The current study identifies statistically significant diurnal variability in dust and dust mixture loading over key dust sources, including the Bodélé Depression, the West African El Djouf, Rub' al-Khali desert, and western and southern North America, confirming the previous observation-based findings regarding the diurnal cycle of dust emission and underlying meteorological processes in these regions. Significant seasonal and diurnal variability in dust and dust mixture is identified over the Iraqi and Thar deserts. The identified significant diurnal cycles in dust mixture loading over the vegetated regions in the Amazon and tropical southern Africa are hypothesized to be driven by enhanced dust emission due to wildfires.

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Eades, Robert, et Kyle Perry. « Evaluation of a 38 L Explosive Chamber for Testing Coal Dust Explosibility ». Journal of Combustion 2019 (2 septembre 2019) : 1–7. http://dx.doi.org/10.1155/2019/5810173.

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Coal dust explosions are the deadliest disasters facing the coal mining industry. Research has been conducted globally on this topic for decades. The first explosibility tests in the United States were performed by the Bureau of Mines using a 20 L chamber. This serves as the basis for all standardized tests used for combustible dusts. The purpose of this paper is to investigate the use of a new 38 L chamber for testing coal dust explosions. The 38 L chamber features design modifications to model the unique conditions present in an underground coal mine when compared to other industries where combustible dust hazards are present. A series of explosibility tests were conducted within the explosive chamber using a sample of Pittsburgh pulverized coal dust and a five kJ Sobbe igniter. Analysis to find the maximum pressure ratio and Kst combustible dust parameter was performed for each trial. Based upon this analysis, observations are made for each concentration regarding whether the explosibility test was under-fueled or over-fueled. Based upon this analysis, a recommendation for future explosibility testing concentrations is made.

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Sahri, Moch, et Merry Sunaryo. « The Analysis of c-silica Dust Content in Respirable Dust in the Ceramic Industry ». Indonesian Journal of Occupational Safety and Health 9, n^o 2 (19 août 2020) : 205. http://dx.doi.org/10.20473/ijosh.v9i2.2020.205-213.

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Introduction: Exposure to hazards in the work environment in the ceramic industry includes silica dust and heat temperatures. The purpose of this research was to analyze the respirable dust and c-silica dust, in addition to calculate c-silica dust in respirated dust. In addition, an evaluation of the results of dust measurements was also carried out by comparing it to the threshold value. Method: This was a descriptive study by testing samples of respirable dust and c-silica dust in the work place. The research was conducted at one of the ceramic industries in East Java. Data collection was carried out on all workers in the production division of 39 peoples. The measurement method for respirable dust analysis used the gravimetric method based on NIOSH method (NMAM 0600, 1998), while the analysis of c-silica dust used XRD equipment in accordance with the NIOSH method (NMAM 7500, 2003). Results: The results of the measurement of respirable dust in 39 respondents obtained a range of values of 0.019 - 0.0563 mg/m3 with an average of 0.19 mg/m3, while for c-silica dust, the results were at the range of 0.0020 - 0.3129 mg/m3 with an average of 0.07 mg/m3. The percentage of c-silica dust content in the ceramics industry in residential dust is different by 5 - 74.3% with the average of 34.89%. Conclusion: Evaluation of the results of measurement of respirable dust found that all samples were below the threshold value, while for c-silica dust, there were 27 samples with values above the threshold. On the average, there is 34.89% level of c-silica in respirable dust in the ceramic industry.Keywords: ceramic industry, c-silica, respirable dust

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Journal, Baghdad Science. « Proparyation of Low frequency microwave in dusty Plasma ». Baghdad Science Journal 5, n^o 3 (7 septembre 2008) : 374–78. http://dx.doi.org/10.21123/bsj.5.3.374-378.

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The numerical simulation for the low frequency waves in dusty plasma has been studied. The studying was done by taking two special cases depending on the direction of the propagation of the wave:First, when the propagation is parallel to the magnetic field K//B,this mode is called acoustic mode.Second,when K B this mode is called cyclotron mode.In addition, every one of the two modes divided into two modes depending on the range of the frequency.The Coulomb coupling parameter was studied, with temperature T,density of the dust particles Nd ,and the charge of the particle Qd.The low frequency electrostatic waves in dusty grains were studied. Also, the properties of ion-acoustic waves and ion-cyclotron waves are shown to modify even through the dust grains do not participate in the wave dynamics. If the dust dynamics induced in the analysis, new “ dust modes “ appear.

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