Inhalation of nail dust from onychomycotic toenails. Part I. Characterization of particles. 1984

1992 ◽  
Vol 82 (2) ◽  
pp. 111-115 ◽  
Author(s):  
C Abramson ◽  
J Wilton

Nail dust particles were analyzed by scanning electron microscopy for size and topography. The percentage of "fines" that could be inhaled and deposited in the alveoli and bronchioles were determined by quantitative particle size analysis. Distribution representing the largest total mass was graphed between 1 and 2 microns. The authors found that 86% of nail dust would reach the bronchioles and alveoli, and 31% could be expected to deposit in these areas.

1977 ◽  
Vol 99 (1) ◽  
pp. 56-60 ◽  
Author(s):  
R. E. Fornes ◽  
M. M. Kleinfelter ◽  
S. P. Hersh

Particle size distributions of dusts generated in a model card room and collected on filter media by a vertical elutriator having a particle size cut-off of 15 μm dia have been determined using scanning electron microscopy. Photomicrographs, usually at 3000×, were made of the samples and the particle diameters were estimated by the Martin method. It was found that the average particle size of cotton dust samples measured by this technique was smaller than that reported in the literature obtained by light microscopy. It was also found that the distribution of particle sizes does not follow a simple log-normal distribution unless the smallest particles observed in this study are omitted. A bimodal or perhaps a multimodal distribution yields a better representation of the data. It is concluded that scanning electron microscopy is a practical and accurate method for sizing cotton dust particles on filter surfaces.


2018 ◽  
Vol 3 (1) ◽  
pp. 12 ◽  
Author(s):  
Zaimahwati Zaimahwati ◽  
Yuniati Yuniati ◽  
Ramzi Jalal ◽  
Syahman Zhafiri ◽  
Yuli Yetri

<p>Pada penelitian ini telah dilakukan isolasi dan karakterisasi bentonit alam menjadi nanopartikel montmorillonit. Bentonit alam yang digunakan diambil dari desa Blangdalam, Kecamatan Nisam Kabupaten Aceh Utara.  Proses isolasi meliputi proses pelarutan dengan aquades, ultrasonic dan proses sedimentasi. Untuk mengetahui karakterisasi montmorillonit dilakukan uji FT-IR, X-RD dan uji morfologi permukaan dengan Scanning Electron Microscopy (SEM). Partikel size analyzer untuk menganalisis dan menentukan ukuran nanopartikel dari isolasi bentonit alam. Dari hasil penelitian didapat ukuran nanopartikel montmorillonit hasil isolasi dari bentonit alam diperoleh berdiameter rata-rata 82,15 nm.</p><p><em>In this research we have isolated and characterized natural bentonite into montmorillonite nanoparticles. Natural bentonite used was taken from Blangdalam village, Nisam sub-district, North Aceh district. The isolation process includes dissolving process with aquades, ultrasonic and sedimentation processes.  The characterization of montmorillonite, FT-IR, X-RD and surface morphology test by Scanning Electron Microscopy (SEM). Particle size analyzer to analyze and determine the size of nanoparticles from natural bentonite insulation. From the research results obtained the size of montmorillonite nanoparticles isolated from natural bentonite obtained an average diameter of 82.15 nm.</em></p>


2018 ◽  
Vol 10 (1) ◽  
pp. 338
Author(s):  
Rachmawati Ramadhana Mustofa ◽  
Iskandarsyah .

Objective: This study aimed to prepare and characterize anti-acne ethosomes using the cold- and thin-layer hydration methods.Methods: A sonication step was included during ethosome preparation to improve the quality of the cold method. Azelaic acid, Phospholipon 90G,ethanol, propylene glycol, and phosphate buffer (pH 7.4) were used in the procedures. Prepared ethosomal suspensions were characterized usingtransmission electron microscopy, particle-size analysis, and spectrophotometry.Results: Ethosomes prepared using the thin-layer hydration method (F1) had small unilamellar vesicles, while those prepared using the cold methodwith 15-min sonication (F4) showed spherical, elliptical, unilamellar, and multilamellar vesicles. F1 ethosomes had a Dmean volume of 648.57±231.26,whereas those prepared using the cold method with 5- (F2), 10- (F3), and 15-min (F4) sonication had Dmean volumes of 2734.04±231.49 nm,948.90±394.52 nm, and 931.69±471.84 nm, respectively. Polydispersity indices of F2, F3, and F4 ethosomes were 0.74±0.21, 0.86±0.05, and 0.91±0.03,respectively, with a poor particle-size distribution, compared to that of F1 (0.39±0.01). Zeta potentials of F1–F4 ethosomes were −38.27±1.72 mV,−23.53±1.04 mV, −31.4±1.04 mV, and −34.3±1.61 mV, respectively. Entrapment efficiencies of F1–F4 ethosomes were 90.71±0.11%, 53.84±3.16%,72.56±0.28%, and 75.11±1.42%, respectively.Conclusion: Anti-acne ethosomes produced using the thin-layer hydration method had superior properties than those produced using the coldmethod with 15-min sonication.


2012 ◽  
Vol 441 ◽  
pp. 261-265 ◽  
Author(s):  
Guo Ping Yao ◽  
Jin Huan Zheng

Vitamin E microcapsules prepared using spray drying were applied to fabrics in thefinishing processby means of padding, and characterization of microcapsules was studied.Experimental conditions for the textile padding process were based on industrial requirements.Morphologies and core-shell structure of the microcapsules and particle size distribution were studiedusing scanning electron microscopy, transmission electron microscopy, and a particle size analyzer.The effectiveness of textile padding (adherence state of microcapsules on textiles and washingfastness) was evaluated by scanning electron microscopy and ultraviolet spectrophotometry. Basedon the present reseach, vitamin E successfully adhered to textiles, and a kind of skin-care product hasbeen developed.


2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Tae-Yub Kwon ◽  
Jung-Yun Ha ◽  
Ju-Na Chun ◽  
Jun Sik Son ◽  
Kyo-Han Kim

Dental modeling resins have been developed for use in areas where highly precise resin structures are needed. The manufacturers claim that these polymethyl methacrylate/methyl methacrylate (PMMA/MMA) resins show little or no shrinkage after polymerization. This study examined the polymerization shrinkage of five dental modeling resins as well as one temporary PMMA/MMA resin (control). The morphology and the particle size of the prepolymerized PMMA powders were investigated by scanning electron microscopy and laser diffraction particle size analysis, respectively. Linear polymerization shrinkage strains of the resins were monitored for 20 minutes using a custom-made linometer, and the final values (at 20 minutes) were converted into volumetric shrinkages. The final volumetric shrinkage values for the modeling resins were statistically similar (P>0.05) or significantly larger (P<0.05) than that of the control resin and were related to the polymerization kinetics (P<0.05) rather than the PMMA bead size (P=0.335). Therefore, the optimal control of the polymerization kinetics seems to be more important for producing high-precision resin structures rather than the use of dental modeling resins.


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