Aerosol Particle Size Research Articles

Assessment of nanoparticles release into the environment during drilling of carbon nanotubes/epoxy and carbon nanofibres/epoxy nanocomposites

The risk assessment, exposure and understanding of the release of embedded carbon nanotubes (CNTs) and carbon nanofibers (CNFs) from commercial high performance composites during machining processes are yet to be fully evaluated and quantified. In this study, CNTs and CNFs were dispersed in epoxy matrix through calendaring process to form nanocomposites. The automated drilling was carried out in a specially designed drilling chamber that allowed elimination of background noise from the measurements. Emission measurements were taken using condensed particle counter (CPC), scanning mobility particle sizer (SMPS) and DMS50 Fast Particulate Size Spectrometer. In comparison to the neat epoxy, the study results revealed that the nano-filled samples produced an increase of 102% and 227% for the EP/CNF and EP/CNT sample respectively in average particle number concentration emission. The particle mass concentration indicated that the EP/CNT and EP/CNF samples released demands a vital new perspective on CNTs and CNFs embedded within nanocomposite materials to be considered and evaluated for occupational exposure assessment. Importantly, the increased concentration observed at 10nm aerosol particle sizes measurements strongly suggest that there are independent CNTs being released at this range.

Experimental study on the penetration efficiency of fine aerosols in thin capillaries

Aerosol penetration efficiency is one of the most important parameters for the safety assessment of a containment shell or containers of radioactive materials. In this work, a practical procedure has been developed to study the penetration efficiency of fine aerosol particles (size < 300nm) through capillaries with bore sizes ranging from 5 to 20µm and lengths from 10mm to 80mm under pressure differences from 60 to 450kPa. The effects of the upstream aerosol concentration, capillary dimension, and pressure difference on the aerosol penetration were investigated, and the relationships between the aerosol penetration efficiency and the air leakage rate as well as the average flow velocity in the capillary were obtained. The results showed that the penetration efficiency of aerosols through a capillary was positively related to the pressure difference as well as the air leakage rate until reaching 100%. For a given air leakage rate, the aerosol penetration efficiency fluctuated within a relatively wide range due to the influence of the pressure difference and capillary dimensions. The aerosol penetration efficiency decreased significantly with increasing capillary length but was identical for capillaries of the same length but different bore sizes. The aerosol penetration efficiency in capillaries showed a better correlation with the average flow velocity than with the air leakage rate. For flow velocities below 5m/s, the aerosol penetration efficiency increased with the air velocity in the capillary, while for velocities above 5m/s, a constant level of approximately 80–100% was maintained.

Differential accumulation of PAHs, elements, and Pb isotopes by five lichen species from the Athabasca Oil Sands Region in Alberta, Canada

A 2014 case study investigated the relative accumulation efficiency of polycyclic aromatic hydrocarbons (PAHs), total sulfur (S), total nitrogen (N), major and minor elements and Pb isotopes in five common lichen species at three boreal forest sites in the Athabasca Oil Sands Region (AOSR) in northeastern Alberta, Canada to identify the optimum lichen species for future biomonitoring. Differences in concentrations of PAHs, multiple elements, and Pb isotopes in fruticose (Bryoria furcellata, Cladina mitis, Evernia mesomorpha) and foliose (Hypogymnia physodes and Tuckermannopsis americana) lichens were found along a 100 km distance gradient from the primary oil sands operations. Integration of insights from emission source samples and oil sands mineralogy in consort with aerosol collection indicates incorporation of more fine particulate matter (PM) into foliose than fruticose lichen biomass. Contrasting PAH with element concentrations allowed lichen species specific accumulation patterns to be identified. The ability of lichen species to incorporate different amounts of gas phase (S and N), petrogenic (V, Ni, Mo), clay (low Si/Al and more rare earth elements), and sand (higher Si/Al and Ti) components from the oil sand operations reflects aerosol particle size and lichen physiology differences that translate into differences in PM transport distances and lichen accumulation efficiencies. Based on these findings Hypogymnia physodes is recommended for future PAH biomonitoring and source attribution studies.

A simplified guide for charged aerosol detection of non-chromophoric compounds—Analytical method development and validation for the HPLC assay of aerosol particle size distribution for amikacin

Amikacin, an aminoglycoside antibiotic lacking a UV chromophore, was developed into a drug product for delivery by inhalation. A robust method for amikacin assay analysis and aerosol particle size distribution (aPSD) determination, with comparable performance to the conventional UV detector was developed using a charged aerosol detector (CAD). The CAD approach involved more parameters for optimization than UV detection due to its sensitivity to trace impurities, non-linear response and narrow dynamic range of signal versus concentration. Through careful selection of the power transformation function value and evaporation temperature, a wider linear dynamic range, improved signal-to-noise ratio and high repeatability were obtained. The influences of mobile phase grade and glassware binding of amikacin during sample preparation were addressed. A weighed (1/X2) least square regression was used for the calibration curve. The limit of quantitation (LOQ) and limit of detection (LOD) for this method were determined to be 5μg/mL and 2μg/mL, respectively. The method was validated over a concentration range of 0.05–2mg/mL. The correlation coefficient for the peak area versus concentration was 1.00 and the y-intercept was 0.2%. The recovery accuracies of triplicate preparations at 0.05, 1.0, and 2.0mg/mL were in the range of 100–101%. The relative standard deviation (Srel) of six replicates at 1.0mg/mL was 1%, and Srel of five injections at the limit of quantitation was 4%. A robust HPLC-CAD method was developed and validated for the determination of the aPSD for amikacin. The CAD method development produced a simplified procedure with minimal variability in results during: routine operation, transfer from one instrument to another, and between different analysts.

Air‐Sea exchange of biogenic volatile organic compounds and the impact on aerosol particle size distributions

AbstractWe report simultaneous, underway eddy covariance measurements of the vertical flux of isoprene, total monoterpenes, and dimethyl sulfide (DMS) over the Northern Atlantic Ocean during fall. Mean isoprene and monoterpene sea‐to‐air vertical fluxes were significantly lower than mean DMS fluxes. While rare, intense monoterpene sea‐to‐air fluxes were observed, coincident with elevated monoterpene mixing ratios. A statistically significant correlation between isoprene vertical flux and short wave radiation was not observed, suggesting that photochemical processes in the surface microlayer did not enhance isoprene emissions in this study region. Calculations of secondary organic aerosol production rates (PSOA) for mean isoprene and monoterpene emission rates sampled here indicate that PSOA is on average &lt;0.1 μg m−3 d−1. Despite modest PSOA, low particle number concentrations permit a sizable role for condensational growth of monoterpene oxidation products in altering particle size distributions and the concentration of cloud condensation nuclei during episodic monoterpene emission events from the ocean.

Determination of dust aerosol particle size at Gale Crater using REMS UVS and Mastcam measurements

AbstractWe calculate the seasonal and interannual variation in dust aerosol particle size above Gale Crater during the first 1413 Martian solar days (sols = 24.6 h) of the Mars Science Laboratory mission. Measurements of UV radiation made by the Rover Environmental Monitoring Station in combination with atmospheric opacities retrieved from the Mastcam instrument are used for the calculations. Our results indicate that the dust effective radius varies significantly with season, ranging from ~0.6 μm during the low opacity season (Ls = 60°–140°) to ~2 μm during the high opacity season (Ls = 180°–360°). Our results suggest that Gale Crater is affected by dust events of high aerosol content originated at various distances from it. Our results improve the accuracy of estimations of ultraviolet radiation fluxes at the Martian surface. Moreover, our results have important implications because the lifetime of suspended dust and its ability to nucleate clouds are affected by particle size.

A Miniature Aerosol Sensor for Detecting Polydisperse Airborne Ultrafine Particles.

Counting and sizing of polydisperse airborne nanoparticles have attracted most attentions owing to increasing widespread presence of airborne engineered nanoparticles or ultrafine particles. Here we report a miniature aerosol sensor to detect particle size distribution of polydisperse ultrafine particles based on ion diffusion charging and electrical detection. The aerosol sensor comprises a couple of planar electrodes printed on two circuit boards assembled in parallel, where charging, precipitation and measurement sections are integrated into one chip, which can detect aerosol particle size in of 30–500 nm, number concentration in range of 5 × 102–5 × 107 /cm3. The average relative errors of the measured aerosol number concentration and the particle size are estimated to be 12.2% and 13.5% respectively. A novel measurement scheme is proposed to actualize a real-time detection of polydisperse particles by successively modulating the measurement voltage and deducing the particle size distribution through a smart data fusion algorithm. The effectiveness of the aerosol sensor is experimentally demonstrated via measurements of polystyrene latex (PSL) aerosol and nucleic acid aerosol, as well as sodium chloride aerosol particles.

Laboratory evaluation of particle size, food contamination, and residual efficacy of pyrethrin + methoprene aerosol

Efficacy of aerosol applications of pyrethrin + methoprene was assessed through emergence of morphologically-normal adults exposed as larvae and through a developmental index. Concrete arenas were treated with aerosol droplets (particles) averaging 2 μm or 16 μm, food material was placed on the arenas at 1–8 weeks post-treatment, and 3-4-week-old larvae of one of four stored product insect species placed on the arenas at the same time. No exposed Lasioderma serricorne (F.) larvae reached the adult stage at either particle size, though they developed further when exposed to residual deposits of the 2 μm aerosol particles compared to residual deposits of 16 μm particles. No exposed larvae of either Tribolium confusum Jacqueline duVal or Trogoderma variabile (Ballion) reached the adult stage when exposed to residues of the 16 μm particles, but most of the larvae exposed to the 2 μm residues completed development. Exposed Dermestes maculatus (DeGeer) larvae completed development to the adult stage after exposure to both particle sizes, indicating low susceptibility to methoprene residues. When food material in the arenas was also treated with the two particle sizes and bioassays conducted using only larvae of L. serricorne, T. confusum, and T. variabile, results were similar to those described above. In a final experiment, only the 16 μm particle size aerosol was used to treat arenas with or without food, with arenas without food having it added one day after treatment. At 1–8 weeks post-treatment, the food was transferred to new untreated arenas and food was replaced in the arenas originally treated with aerosol. Bioassays were conducted using only larvae of T. confusum and T. variabile. The food material blocked deposition of the aerosol on the arenas or absorbed some of the residues, indicating transference of the methoprene residues from the treated surfaces onto the food.

A simple method for assaying colistimethate sodium in pharmaceutical aerosol samples using high performance liquid chromatography

A rapid and simple reversed-phase high performance liquid chromatography (HPLC) method for the quantitation of colistimethate sodium in pharmaceutical formulations has been developed. The chromatographic separation was performed using a Phenomenex Kinetex XB-C18 column with gradient elution using a mobile phase containing acetonitrile and 32mM sodium sulphate. Quantitation is based on the sum of the areas of two prominent peaks in the chromatogram, which produces a total peak area that is stable for 120 sample injections. The HPLC method was validated over the range 0.05–7mg/mL, and was shown to be suitable for the analysis of aerosolised pharmaceuticals in terms of aerosol output onto filter and for the analysis of samples from a cascade impactor, which is used for the determination of aerosol particle size.

A new aerosol wet removal scheme for the Lagrangian particle model FLEXPART v10

Abstract. A new, more physically based wet removal scheme for aerosols has been implemented in the Lagrangian particle dispersion model FLEXPART. It uses three-dimensional cloud water fields from the European Centre for Medium-Range Weather Forecasts (ECMWF) to determine cloud extent and distinguishes between in-cloud and below-cloud scavenging. The new in-cloud nucleation scavenging depends on cloud water phase (liquid, ice or mixed-phase), based on the aerosol's prescribed efficiency to serve as ice crystal nuclei and liquid water nuclei, respectively. The impaction scavenging scheme now parameterizes below-cloud removal as a function of aerosol particle size and precipitation type (snow or rain) and intensity.Sensitivity tests with the new scavenging scheme and comparisons with observational data were conducted for three distinct types of primary aerosols, which pose different challenges for modeling wet scavenging due to their differences in solubility, volatility and size distribution: (1) 137Cs released during the Fukushima nuclear accident attached mainly to highly soluble sulphate aerosol particles, (2) black carbon (BC) aerosol particles, and (3) mineral dust. Calculated e-folding lifetimes of accumulation mode aerosols for these three aerosol types were 11.7, 16.0, and 31.6 days respectively, when well mixed in the atmosphere. These are longer lifetimes than those obtained by the previous removal schem, and, for mineral dust in particular, primarily result from very slow in-cloud removal, which globally is the primary removal mechanism for these accumulation mode particles.Calculated e-folding lifetimes in FLEXPART also have a strong size dependence, with the longest lifetimes found for the accumulation-mode aerosols. For example, for dust particles emitted at the surface the lifetimes were 13.8 days for particles with 1 µm diameter and a few hours for 10 µm particles. A strong size dependence in below-cloud scavenging, combined with increased dry removal, is the primary reason for the shorter lifetimes of the larger particles. The most frequent removal is in-cloud scavenging (85 % of all scavenging events) but it occurs primarily in the free troposphere, while below-cloud removal is more frequent below 1000 m (52 % of all events) and can be important for the initial fate of species emitted at the surface, such as those examined here.For assumed realistic in-cloud removal efficiencies, both BC and sulphate have a slight overestimation of observed atmospheric concentrations (a factor of 1.6 and 1.2 respectively). However, this overestimation is largest close to the sources and thus appears more related to overestimated emissions rather than underestimated removal. The new aerosol wet removal scheme of FLEXPART incorporates more realistic information about clouds and aerosol properties and it compares better with both observed lifetimes and concentration than the old scheme.

Evidence for secondary ice production in Southern Ocean open cellular convection

Ice particles present at temperatures warmer than −9 °C were encountered in unexpectedly high number concentrations (up to 54 L−1) by an instrumented aircraft over the Southern Ocean (SO), off the southwest coast of Tasmania, Australia, on 7 September 2013. The sampled clouds were precipitating, characterized by mixed‐phase, open‐cellular shallow convection. These clouds were present within a large‐scale environment characterized by cold air advection, in a pristine air mass for over 72 h. Using a Cloud and Aerosol Spectrometer, aerosol particles (diameters &gt; 0.6 µm) size and number concentrations were measured and ice nucleating particle (INP) number concentrations were estimated with a recognized ice nuclei parametrization scheme. The estimated INP number concentrations were in the range of 10−5–10−1 L−1 at temperature above −9 °C, which is up to three orders of magnitude less than the ice number concentrations typically observed. The high ice number concentrations are largely consistent with the theoretical values when ice crystals are produced via a splinter production. The evidence suggests that secondary ice processes (likely the Hallett–Mossop mechanism) were playing a key role in generating the high ice number concentrations observed. Satellite observations from an A‐Train overpass in the neighbourhood during the flight period reveal a qualitatively consistent story, with patchy, mixed‐phase (but predominantly supercooled liquid water) clouds observed at cloud‐top temperatures around −6 °C. Using back trajectory calculations, these clouds are tracked over 23 and 46 h with A‐Train observations. The presence of these clouds is found to be common over the SO during this period of time. This suggests that the ice particles present in a relatively warm temperature range could potentially be commonplace, within the widespread (up to thousands of kilometres) shallow convective cloud fields over the SO. These clouds may have important implication for the energy budget and precipitation production over this climatically important region.

Experimental evidence of the rear capture of aerosol particles by raindrops

Abstract. This article presents new measurements of the efficiency with which aerosol particles of accumulation mode size are collected by a 1.25 mm sized raindrop. These laboratory measurements provide the link to reconcile the scavenging coefficients obtained from theoretical approaches with those from experimental studies. We provide here experimental proof of the rear capture mechanism in the flow around drops, which has a fundamental effect on submicroscopic particles. These experiments thus confirm the efficiencies theoretically simulated by Beard (1974). Finally, we propose a semi-analytical expression to take into account this essential mechanism to calculate the collection efficiency for drops within the rain size range.

Aerosol particle size distribution of atmospheric lead-210 in northern Finland

Size-segregated aerosol samples were collected with a high-volume 6-stage cascade impactor at Sodankylä, Finland, 100 km north of the Arctic Circle. The 210Pb content of the samples were determined with radiochemical separation of in-grown 210Po followed by alpha spectrometry. Most of the 210Pb activity was incorporated in accumulation mode aerosol particles. The activity median aerodynamic diameter (AMAD) ranged from 0.53 μm to 0.98 μm 38–61 per cent of 210Pb activity was found to be associated with aerosol particles smaller than 0.69 μm. A slight downward tendency of 210Pb activity median aerodynamic diameter was observed as a function of increasing 210Pb activity concentration. This is related to the continental origin of airborne 210Pb on one hand, and various aerosol particle growth processes on the other hand. Also a clear tendency towards a higher 7Be/210Pb activity ratio as a function of increasing aerosol particle diameter was observed. This, in turn, reflects the different origin of 210Pb, exhalation of 222Rn from the soil into the air, and 7Be, formation by cosmic radiation in the upper troposphere and the stratosphere.

Morphology, Composition, and Mixing State of Individual Aerosol Particles in Northeast China during Wintertime

Northeast China is located in a high latitude area of the world and undergoes a cold season that lasts six months each year. Recently, regional haze episodes with high concentrations of fine particles (PM2.5) have frequently been occurring in Northeast China during the heating period, but little information has been available. Aerosol particles were collected in winter at a site in a suburban county town (T1) and a site in a background rural area (T2). Morphology, size, elemental composition, and mixing state of individual aerosol particles were characterized by transmission electron microscopy (TEM). Aerosol particles were mainly composed of organic matter (OM) and S-rich and certain amounts of soot and K-rich. OM represented the most abundant particles, accounting for 60.7% and 53.5% at the T1 and T2 sites, respectively. Abundant spherical OM particles were likely emitted directly from coal-burning stoves. Soot decreased from 16.9% at the T1 site to 4.6% at the T2 site and sulfate particles decrease from 35.9% at the T2 site to 15.7% at the T1 site, suggesting that long-range transport air masses experienced more aging processes and produced more secondary particles. Based on our investigations, we proposed that emissions from coal-burning stoves in most rural areas of the west part of Northeast China can induce regional haze episodes.

Detection of nanoparticles released at finishing of dental composite materials

Newly developed dental composite materials contain increased concentrations of filler particles of the nanometer size to produce materials with high mechanical and wear resistance, improved polishability, and long-lasting gloss. With nanocomposites, however, a question arises on possible health risk caused by filler nanoparticles released during finishing and polishing nanocomposite restorations in dental cabinets. As data in the current literature are conflicting, our study was focused on detailed characterization of aerosol particles released during grinding nanocomposites Filtek Ultimate and Estelite Sigma Quick by diamond and tungsten carbide bladed burs. The results were compared with the aerosol particle size obtained from a composite Charisma reinforced with micrometer-size filler particles and an unfilled resin. Using a scanning mobility particle sizer and aerodynamic particle sizer, the release of nano- and micro-sized particles generated during high-speed grinding was detected. The mode of nanoparticle size distribution ranged not only from less than 16.0 to 51.6 nm for both nanocomposites, but also for the microhybrid composite and the unfilled resin. However, the amount of nanoparticles in the aerosol (5.0–68) × 103 cm−3 was not high exceeding 1–8.5 times their background concentration. The release of nanoparticles independently on the filler particle size and their content might suggest that the aerosol nanoparticles may originate from thermal decomposition of composite polymeric matrix due to friction heat rather than from filler nanoparticles. Due to the potential adverse health effects of nanoparticles, more detailed research is needed to investigate the effect of finishing conditions on the nanoparticle generation and their chemical composition to avoid any potential risk to dental staff. A study of the aerosol formed during grinding with water cooling to avoid heating will also be carried out.

Determination of the Size Distribution of Radioactive Aerosols in the IVV-2M Reactor Room Atmosphere

The results of a determination of the particle size of radioactive aerosols in the reactor room of the IVV-2M reactor facility at the Institute of Reactor Materials are presented. A four-stage diffusion battery with mesh catching elements and a five-stage setup was used to determine the size of aerosol particles. This sampling arrangement makes it possible to study the distribution of radioactive aerosols in the size range 0.5 nm to 23 μm. The gas–aerosol mixture studied in the reactor room contains the radioactive noble gases 138Xe and 88Kr, their decay products 138Cs and 88Rb, and the fission product 132Te. Three basic modes in the range of ultrafine aerosols with active median thermodynamic diameter 0.7, 6, and 35 nm were obtained for this mixture. The relative amount of the aerosols of size 0.5 μm were detected.

Quantification of leakage of sub-micron aerosols through surgical masks and facemasks for pediatric use

ABSTRACTSurgical respirators, surgical masks (SMs), and facemasks for pediatric use (FPUs) are routinely used in the U.S. healthcare industry as personal protective equipment (PPE) against infectious diseases. While N95s including surgical respirators have been routinely studied, SMs and FPUs have not received as much attention, particularly in the context of aerosolized threats. This is because SMs and PFUs are not designed to protect against sub-micron aerosols. However, with the possibility of new or re-emerging airborne diseases or bio-aerosol weapons lingering, combined with the limited availability of respirators and logistical issues associated with fit-testing millions, the general adult and pediatric populations may elect to wear SMs and FPUs, respectively, in the case of a pandemic or a bio-terrorist attack. When a person dons a PPE, gaps are created between the wearer's face and the PPE, and aerosols leaking through these gaps can be an important contributor to the risk of infection compared to filtered aerosols. To understand and quantify the contribution of leakage of aerosols through gaps, with particular emphasis on SMs and FPUs, this study investigated leakage of charge-neutralized, polydispersed, dried sodium-chloride aerosols across different brands of PPE. Different breathing rates, aerosol particle sizes, and gap sizes were considered. A few major findings of this study were: (a) leakage, is not a strong function of sub-micron aerosol size; (b) for the same gap size, leakage of aerosols through surgical respirators can often be higher than in SMs and FPUs; and (c) as the gap size increases, the increase in leakage through surgical respirators is higher compared for SMs and FPUs, implying that some SMs and FPUs that possess electret layers may be preferable to N95s that have not been fit-tested. The results obtained can also be used to explain conflicting findings from clinical studies on the effectiveness of SMs when compared to N95s and can be input into risk-assessment models to determine the increase in infection rate resulting from deployment of PPE under less-than-ideal conditions.

Role of Sodium in Coal in Determining Deposition Rates

The alkali content in the ash is commonly thought to be the “bad actor” in determining coal ash deposition rates on boiler heat transfer surfaces. This paper reports results of 16 tests in which ash aerosol deposition rates were measured for three coals, burned under air- and oxy-fired combustion conditions. A 100 kW down-fired laboratory combustor coupled with a specially designed deposition probe was employed. Ash aerosol particle size distributions and size-segregated compositions were measured using electric-mobility, light-scattering, and low-pressure impactor techniques. Net sodium vaporization (assumed to be the fraction of sodium collected as a <0.6 μm fume) was compared to literature data. For ash deposition rates, emphasis was on the tightly bonded “inside” deposits rather than the loosely bound “outside” deposits, which could not be collected or weighed precisely. Over a limited range of these tests, where PM1 was indeed greatly enriched in sodium, deposition rates did correlate with the sodium...

Influences of aerosol physiochemical properties and new particle formation on CCN activity from observation at a suburban site of China

With the aim of understanding the impact of aerosol particle size and chemical composition on CCN activity, the size-resolved cloud condensation nuclei (CCN) number concentration (NCCN), particle number size distribution (PSD) (10–600nm), and bulk chemical composition of particles with a diameter <1.0μm (PM1) were measured simultaneously at Xinzhou, a suburban site in northern China, from 22 July to 26 August 2014. The NCCN was measured at five different supersaturations (SS) ranging from 0.075%–0.76%. Diurnal variations in the aerosol number concentration (NCN), NCCN, the bulk aerosol activation ratio (AR), the hygroscopicity parameter (κchem), and the ratio of 44 mass to charge ration (m/z 44) to total organic signal in the component spectrum (f44), and the PSD were examined integrally to study the influence of particle size and chemical composition on CCN activation. We found that particle size was more related to the CCN activation ratios in the morning, whereas in the afternoon (~1400 LST), κchem and f44 were more closely associated with the bulk AR. Assuming the internal mixing of aerosol particles, NCCN was estimated using the bulk chemical composition and real-time PSD. We found that the predicted CCN number concentrations were underestimated by 20–30% at SS <0.2% probably due to the measurement uncertainties. Estimates were more accurate at higher SS levels, suggesting that the hygroscopicity parameter based on bulk chemical composition information can provide a good estimate of CCN number concentrations. We studied the impacts of new particle formation (NPF) events on size-resolved CCN activity at the “growth” stage and “leveling-off” stage during a typical NPF event by comparing with the case during non-NPF event. It has been found that CCN activation was restrained at the “growth” stage during which larger particle diameters were needed to reach an activation diameter(Da), and the bulk AR decreased as well. However, during the “leveling-off” stage, a lower Da was observed and CCN activation was greatly enhanced.

Analytical Capabilities of Spark Sampling Device for ICP-AES Analysis of Metal Samples

The analytical performance of a spark sampling device “Aspect” (“VMK-Optoelektronika”) is evaluated for steel analysis by atomic emission spectrometry with inductively coupled plasma (ICP-AES). The results of studying the effect of pulse duration, frequency and current of the spark discharge on the character of sample erosion, size and quantity of aerosol particles are presented. The dependences of the analytical signal on the spark duration are obtained and the optimal duration of preliminary sparking is specified. The limit of Cr, Cu, Mn, Mo, Ni, P, Si, and V detection ranges from n x 10 5 to n x 10 2 % wt. The accuracy of the ICP-AES analysis with a spark sampling using standard reference sample showed the good agreement between certified and determined values of analyte concentration.