Particle Size Distribution of Airborne Dusts Using a Scanning Electron Microscope

Silver powders produced by both electrochemical (galvanostatic (DC) and potentiostatic (POT) regimes of electrolysis) and chemical processes were examined by scanning electron microscope, and particle size distribution (PSD) of the obtained particles was done. In the DC regime, the current densities of ?14.4 mA cm-2 for the nitrate (NIT; powder denoted with DC(NIT)) and ?13.05 mA cm-2 for the ammonium (AM; DC(AM)) electrolytes were applied. In the POT regime, the used overpotentials were ?90 mV (NIT(90)) and ?150 mV (NIT(150)) for the nitrate, and ?625 mV (AM(625)) and ?925 mV (AM(925)) for the ammonium electrolytes. Reduction with hydrazine was used for chemical synthesis (powder denoted with HYD). On the basis of SEM and PSD analysis, Ag powders were grouped into three groups. In the first group DC(AM), AM(925) and HYD powders with the (8.4?8.9 %) volume ratios were placed. In the second group were AM(625) and DC(NIT) powders with the (6.5?6.6 %) volume ratios. NIT(90) and NIT(150) powders with the volume ratios of (5.2?5.7 %) made the third group. The obtained volume ratios were correlated with the morphology of synthesized particles in order to perceive advantages and lacks of powder production via electrochemical and chemical routes.

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Determination of Particle Size Distribution of Used Black Tea Leaves by Scanning Electron Microscope

Dhaka University Journal of Science ◽

10.3329/dujs.v61i1.15106 ◽

2013 ◽

Vol 61 (1) ◽

pp. 111-115 ◽

Cited By ~ 5

Author(s):

Mohammad Abul Hossain ◽

Shigeru Mori

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Particle Size Distribution ◽

Size Distribution ◽

Black Tea ◽

Tea Leaves ◽

Sem Images ◽

Scanning Electron

The particle size distribution (PSD) of a particulate material is important in understanding its physical and chemical properties. Determination of PSD is essential in many physicochemical processes and production quality depends on the measurement and control of PSD. Scanning electron microscope (SEM), in addition to sieve analysis, has been used to determine the PSD of biomass materials like used black tea leaves (UBTL). Spherical, ellipsoidal and non-spherical particles of used black tea leaves were observed in SEM images. The PSD of four different sizes ranges of spherical and non spherical UBTL particles was determined from the measurement of SEM images of length wise and width wise diameters. The results enabled to determine the mean diameter or representative diameters of particles of wide size ranges. Dhaka Univ. J. Sci. 61(1): 111-115, 2013 (January) DOI: http://dx.doi.org/10.3329/dujs.v61i1.15106

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FABRICATION OF 2-5 µM HYGROSCOPIC SEEDING MATERIAL FOR RAIN ENHANCEMENT PURPOSES

Jurnal Sains & Teknologi Modifikasi Cuaca ◽

10.29122/jstmc.v22i1.4599 ◽

2021 ◽

Vol 22 (1) ◽

pp. 35-39

Author(s):

Dini Harsanti ◽

Krisna Adhitya ◽

Safrizal Safrizal

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Size Distribution ◽

Cloud Condensation Nuclei ◽

Condensation Nuclei ◽

Seeding Material ◽

Rough Milling ◽

Jet Milling ◽

Scanning Electron

Abstract Hygroscopic cloud seeding, which uses giant cloud condensation nuclei (GCCN) particles with diameters between 2-5 µm, has been known to be 100 times more effective compared to those that use hygroscopic flares. Micronisation through jet milling has been recognized as the most common and ubiquitous method used to obtain particles with such a narrow size (2-5 µm) distribution. This research has successfully developed and identified 2-5 µm NaCl powders mixed with 10% cab-o-sil anticaking agent and 2 (two) times jet milling frequency as a potential GCCN (hygroscopic) seeding material. We use a combination of jet mill micronisation, rough milling with a Cross-Beather Mill, and analytical sieving to produce powders with those mentioned above (2-5 µm) size distribution. We varied the anticaking agent percentage in the mixture and the jet milling process frequency to identify which parameters would result in the 2-5 µm size distribution. We then confirmed the micronisation results particle size distribution with a particle size analyzer (PSA) and its morphology with a scanning electron microscope (SEM) machine. The materials with the 10% cab-o-sil agent mixture were confirmed to have the aforementioned size distribution from the characterization results. Intisari Penyemaian awan higroskopis menggunakan partikel giant cloud condensation nuclei (GCCN) dengan diameter 2-5 m telah diketahui 100 kali lebih efektif dibandingkan dengan yang menggunakan flare higroskopis. Mikronisasi melalui jet milling telah dikenal sebagai metode yang paling umum dan banyak digunakan untuk mendapatkan partikel dengan distribusi ukuran sempit (2-5 µm). Penelitian ini berhasil mengembangkan dan mengidentifikasi serbuk NaCl 2-5 µm yang dicampur dengan 10% anti gumpal berupa Cab-O-Sil dan frekuensi jet milling 2 (dua) kali sebagai bahan penyemaian GCCN (higroskopis) potensial. Pada penelitian ini telah digunakan kombinasi mikronisasi jet mill, penggilingan kasar dengan Cross-Beather Mill, dan ayakan analitik untuk menghasilkan serbuk dengan distribusi ukuran yang disebutkan di atas (2-5 µm). Telah divariasikan pula persentase bahan anti gumpal dalam campuran dan frekuensi proses jet milling untuk mengidentifikasi parameter yang akan menghasilkan distribusi ukuran 2-5 µm. Distribusi ukuran partikel hasil mikronisasi tersebut kemudian dikonfirmasi dengan alat analisa ukuran partikel (PSA) dan morfologinya dengan mesin scanning electron microscope (SEM). Dari hasil karakterisasi, material dengan campuran anti gumpal Cab-O-Sil sebanyak 10% dipastikan memiliki sebaran ukuran tersebut.

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Evolución de la microestructura en aleaciones de acero inoxidable Fe-Cr preparadas por pulvimetalurgia

Respuestas ◽

10.22463/0122820x.403 ◽

2016 ◽

Vol 15 (2) ◽

pp. 5-9

Author(s):

Armando Sarmiento Santos

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Powder Metallurgy ◽

Scanning Electron Microscope ◽

Particle Size Distribution ◽

Chromium Content ◽

Density Variation ◽

X Ray ◽

Lower Porosity ◽

Scanning Electron

Se estudia la influencia de los procesos utilizados durante las etapas de preparación de muestras por pulvimetalurgia, en algunas de las características de aleaciones inoxidables de Fe-Cr. Para ello se preparan muestras Fe-Cr con concentraciones de cromo entre 13,9 y 28,4 % en peso, se correlaciona el comportamiento de la variación de densidad de las muestras con su contenido de cromo y con los parámetros del proceso. Las muestras se someten a análisis elemental con la microsonda de rayos X acoplada al microscopio electrónico de barrido para corroborar los correspondientes contenidos de cromo. También fue observada la microestructura para las muestras con diferentes concentraciones de cromo. A partir de los análisis realizados se encontró una mayor densificación en las muestras con mayores contenidos de cromo, las cuales corresponden a una distribución de tamaño de partícula más ancha. Del estudio de la microestructura de las muestras, en función del contenido de cromo, se observa un mayor crecimiento de grano y menor porosidad en muestras con menor contenido de cromo.Palabras clave: pulvimetalurgia, aleaciones inoxidables, cromoAbstractThe influence of the processes used during the stages of sample preparation by powder metallurgy, in some of the characteristics of Fe-Cr stainless alloys, are studied. For this will prepared Fe-Cr samples with chromium concentrations between 13.9 and 28.4% by weight. The behavior of the density variation of samples with chromium content and process parameters were correlated. The samples were subjected to elemental analysis with X-ray microprobe coupled to a scanning electron microscope to confirm the relevant contents of chromium. Microstructure was also observed for samples with different chromium concentrations. From the analysis, we found a higher density in samples with higher chromium contents, which correspond to a wider particle size distribution. The study of samples microstructure, as a function of chromium content, reveals a higher grain growth and lower porosity in samples with lower chromium content. Keywords: powder metallurgy, stainless alloys, chromium

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Effect of Kaolin Particle Size Towards Preparation of Kaolin Ceramic Membrane

Emerging Advances in Integrated Technology ◽

10.30880/emait.2021.02.01.005 ◽

2021 ◽

Vol 02 (01) ◽

Author(s):

Siti Khadijah Hubadillah ◽

◽

Norsiah Hami ◽

Nurul Azita Salleh ◽

Mohd Riduan Jamalludin ◽

...

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Field Emission ◽

Preliminary Data ◽

Membrane Structure ◽

Ceramic Membrane ◽

Low Cost ◽

Dense Structure ◽

Scanning Electron

The purpose of this work is to study the effect of kaolin particle size for the preparation of low cost ceramic membrane suspension and ceramic membrane structure. Kaolin particle size is categorized into two categories; i) ≤ 1µm and ii) ≥ 1 µm. The suspension is prepared via stirring technique under 1000 rpm at 60°C. The particle size of kaolin is characterized using field emission scanning electron microscope (FESEM) and the prepared suspension is characterized in term of its viscosity. Results indicate that the particle size gave significant effect to the viscosity of ceramic membrane suspension. Preliminary data showed that kaolin with particle size ≤ 1µm resulted ceramic membrane with dense structure.

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Exploring the Parameter Space of Point Spread Function Determination for the Scanning Electron Microscope—Part II: Effect on Image Restoration Quality

Microscopy and Microanalysis ◽

10.1017/s1431927619014831 ◽

2019 ◽

Vol 25 (05) ◽

pp. 1183-1194

Author(s):

Mandy C. Nevins ◽

Richard K. Hailstone ◽

Eric Lifshin

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Image Quality ◽

Scanning Electron Microscope ◽

Image Restoration ◽

Point Spread Function ◽

Background Correction ◽

Point Spread ◽

Spread Function ◽

Scanning Electron

AbstractPoint spread function (PSF) deconvolution is an attractive software-based technique for resolution improvement in the scanning electron microscope (SEM) because it can restore information which has been blurred by challenging operating conditions. In Part 1, we studied a modern PSF determination method for SEM and explored how various parameters affected the method's ability to accurately estimate the PSF. In Part 2, we extend this exploration to PSF deconvolution for image restoration. The parameters include reference particle size, PSF smoothing (K), background correction, and restoration denoising (λ). Image quality was assessed by visual inspection and Fourier analysis. Overall, PSF deconvolution improved image quality. Low λ enhanced image sharpness at the cost of noise, while high λ created smoother restorations with less detail. λ should be chosen to balance feature preservation and denoising based on the application. Reference particle size within ±0.9 nm and K within a reasonable range had little effect on restoration quality. Restorations using background-corrected PSFs had superior quality compared with using no background correction, but if the correction was too high, the PSF was cut off causing blurrier restorations. Future efforts to automatically determine parameters would remove user guesswork, improve this method's consistency, and maximize interpretability of outputs.

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Automation of size fractionation to extract clays and silts

Clay Minerals ◽

10.1180/claymin.2011.046.3.515 ◽

2011 ◽

Vol 46 (3) ◽

pp. 515-523 ◽

Cited By ~ 2

Author(s):

Youjun Deng ◽

M. G. Tenorio Arvide

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Laser Diffraction ◽

Size Fractionation ◽

Microscope Examination ◽

Household Appliance ◽

Lawn Irrigation ◽

Sedimentation Time ◽

Scanning Electron

AbstractThe objective of this study was to build an automated size fractionator to process up to 16 samples at one time. Most parts used in the apparatus are inexpensive items, available from lawn irrigation, household appliance and aquatic pet supply stores. The device can be used to extract different silt and clay fractions by changing sedimentation time. A bentonite, a kaolin and an ironoxide-rich Oxisol were fractionated by this instrument to sequentially extract particles that have sizes equivalent to <2 µm, <5 µm, <10 µm and <20 µm quartz spheres. A laser diffraction particle size analyser revealed size differences in the different fractions and also showed that the silt fractions contained particles having slightly larger sizes than the assumed diameters of spherical quartz. Scanning electron microscope examination suggested that the greater particle size was mainly due to the non-spherical shapes of the particles and a reduced bulk density of the porous aggregates.

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Effect of Different Abrasives on Chemical Mechanical Polishing for Magnesia Alumina Spinel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.866.115 ◽

2020 ◽

Vol 866 ◽

pp. 115-124

Author(s):

Zhan Kui Wang ◽

Ming Hua Pang ◽

Jian Xiu Su ◽

Jian Guo Yao

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Chemical Mechanical Polishing ◽

Removal Rate ◽

Mechanical Polishing ◽

Key Factors ◽

Particle Size Analyzer ◽

Scanning Electron ◽

Shape And Size

In this paper, a series of chemical mechanical polishing (CMP) experiments for magnesia alumina (Mg-Al) spinel were carried out with different abrasives, and the materials removal rate (MRR) and surface quality was evaluated to explore their different effects. The scanning electron microscope (SEM) and laser particle size analyzer were also employed to test the micro-shape and size distribution of abrasives. Then, the mechanism of different effects with different abrasives was analyzed in CMP for Mg-Al spinel. Those experimental results suggest that different subjecting pressure ratios of abrasives to polishing pad with different abrasive are the key factors leading to difference polishing performances in CMP.

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Preparation of Cr2O3 Nanoparticles via Hydrothermal Reduction of CH3OH

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.760 ◽

2012 ◽

Vol 463-464 ◽

pp. 760-763

Author(s):

Zhen Zhao Pei ◽

Hong Bin Xu ◽

Yi Zhang

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Average Particle Size ◽

Average Particle ◽

Calcination Temperatures ◽

Cr2o3 Nanoparticles ◽

Average Size ◽

Hydrothermal Reduction ◽

Scanning Electron

Nanoparticles of Cr2O3 were successfully obtained via hydrothermal reduction of CH3OH. The oxidant and chromium source was CrO3. The process needs no stirrer or surfactant and the CrO3 concentration was 0.83mol/L. The obtained products were loosely agglomerated Cr2O3 nanoparticles with the average size of 29 to 79 nm. Influences of reactant ratios and calcination temperatures on the specific surface area and average particle size were discussed. And the morphology of nanoparticles was investigated by use of field-emission scanning electron microscope.

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Synthesis and properties of TiO2, NiO and ZnO nanoparticles and their possible biomedical application

Archives of Materials Science and Engineering ◽

10.5604/01.3001.0013.4612 ◽

2019 ◽

Vol 2 (98) ◽

pp. 81-84

Author(s):

K. Szmajnta ◽

M. Szindler

Keyword(s):

Particle Size ◽

Electron Microscope ◽

Chemical Composition ◽

Particle Size Distribution ◽

Size Distribution ◽

Biomedical Application ◽

Sol Gel ◽

Scattering Method ◽

Gel Method ◽

Sol Gel Method

Purpose: The main purpose of this publication is to bring closer method of synthesis and examining basic properties of TiO2, ZnO and NiO nanoparticles (NPs), and investigate their possible biomedical application. Design/methodology/approach: Nanopowders were made with sol-gel method. Surface morphology studies of the obtained materials were made using Zeiss's Supra 35 scanning electron microscope and the structure using S/TEM TITAN 80-300 transmission electron microscope. In order to confirm the chemical composition of observed nanopowders, qualitative tests were performed by means of spectroscopy of scattered X -ray energy using the Energy Dispersive Spectrometer (EDS). The DLS (Dynamic Light Scattering) method was used to analyse the particle size distribution using the AntonPaar Litesizer 500 nanoparticle size analyser. Changes in particle size distribution at elevated temperatures were also observed. The TiO2, ZnO and NiO NPs with spherical shape were successfully produced by sol-gel method. Findings: The diameter of the as prepared nanoparticles does not exceed 25 nm which is confirmed by the TEM analysis. The highest proportion among the agglomerates of the nanoparticles has been shown to show those with a diameter of 80 to 125 nm. The qualitative analysis of EDS confirmed the chemical composition of the material. Practical implications: Nanoparticles (NPs) has been receiving an incrementally increasing interest within biomedical fields researchers. Nanoparticles properties (physical, chemical, mechanical, optical, electrical, magnetic, etc.) are different from the properties of their counterparts with a larger particle size. Originality/value: The nanoparticles were prepared using sol-gel method which allows the particle size to be controlled in a simple way.

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