A Low Cost Correlative Technique for Cell Imaging via Confocal and Scanning Electron Microscopy

Purpose: To report the use of hexamethyldisilazane (HMDS) as an alternative to critical point drying for preparing stented canine peripheral vessels for scanning electron microscopy (SEM). Technique: Vascular specimens were fixed in 4% formaldehyde overnight, dehydrated in a graded ethanol series, followed by immersion in 100% hexamethyldisilazane. After air drying, the specimens were mounted on stainless steel stubs, coated with gold, and examined in the SEM. The electron micrographs were of high quality, showing the layers of the vascular wall and the incorporated stent covered by a neointimal layer. The micrographs were comparable to corresponding histological sections, but detailed endothelial patterns were more visible. Conclusions: HMDS treatment and subsequent air drying provides good quality scanning electron micrographs that reveal both endothelial patterns and the layered architecture of stented vessels. The disadvantage of HMDS drying may be a shrinkage and distortion similar to other drying agents. Ease of handling, low cost, and a high rate of success are advantages that favor HMDS desiccation over other drying methods.

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Reprocessing N95 Respirators During the COVID-19 Pandemic: Moist Heat Inactivates SARS-CoV-2 and Maintains N95 Filtration

10.1101/2020.05.25.20112615 ◽

2020 ◽

Cited By ~ 1

Author(s):

Simeon C. Daeschler ◽

Niclas Manson ◽

Kariym Joachim ◽

Alex W. H. Chin ◽

Katelyn Chan ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Low Cost ◽

Filtration Efficiency ◽

Term Care ◽

Protective Function ◽

E Coli ◽

Breathing Resistance ◽

N95 Respirators ◽

Scanning Electron

AbstractBackgroundThe unprecedented demand and consequent global shortage of N95 respirators during the COVID-19 pandemic have left frontline workers vulnerable to infection. To potentially expand the supply, we validated a rapidly applicable low-cost decontamination protocol in compliance with regulatory standards to enable the safe reuse of personalized, disposable N95-respirators.MethodsFour common models of N95-respirators were disinfected for 60 minutes at 70°C either at 0% or 50% relative humidity (RH). Effective inactivation of SARS-CoV-2 and E. coli was evaluated in inoculated masks. The N95 filter integrity was examined with scanning electron microscopy. The protective function of disinfected N95 respirators was tested against US NIOSH standards for particle filtration efficiency, breathing resistance and respirator fit.ResultsA single heat treatment inactivated both SARS-CoV-2 (undetectable, detection limit: 100 TCID50/ml) and E. coli (0 colonies at 50%RH) in all four respirator models. Even N95-respirators that underwent ten decontamination cycles maintained their integrity and met US-governmental criteria for approval regarding fit, filtration efficiency and breathing resistance. Scanning electron microscopy demonstrated maintained N95 fiber diameter compared to baseline.InterpretationThermal disinfection enables large-scale, low cost decontamination of existing N95 respirators using commonly sourced equipment during the COVID-19 pandemic. This process could be used in hospitals and long term care facilities and also provides a feasible approach to expand the N95 supply in low- and middle-income regions.

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A Magnetic Array Fabricated by a Novel Process Constructed with Photosensitive Polyimide-Ferrite Nanocomposite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.499.3 ◽

2012 ◽

Vol 499 ◽

pp. 3-6

Author(s):

Yuan Xun Li ◽

Huai Wu Zhang ◽

Ying Li Liu ◽

Jie Li

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Magnetic Nanoparticles ◽

Barium Ferrite ◽

Low Cost ◽

Simple Process ◽

Micrometer Scale ◽

Scanning Electron

The authors report an approach to the fabrication of a periodic magnetic array using photosensitive polyimide-barium ferrite nanocomposite. These patterns are shaped by a some-like imprint technique, under the interactions between the magnetic nanoparticles and permanent magnetic mold. Scanning electron microscopy has been used to characterize the magnetic array and well-defined structures with magnetic arrays are obtained. The diameter of each dot is as small as 52um. The presented concept leads to a realization of a magnetic array, which offers advances in achieving micrometer-scale patterns with a very low cost and simple process.

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Synthesis of silica of rice husk modification (3-aminopropyl) trietoxysilane for adsorption methylene blue

MATEC Web of Conferences ◽

10.1051/matecconf/201819709009 ◽

2018 ◽

Vol 197 ◽

pp. 09009

Author(s):

Yusmaniar Yusmaniar ◽

Darsef Darwis ◽

Afrizal Afrizal ◽

Annisa Annisa

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Methylene Blue ◽

Surface Area ◽

Adsorption Process ◽

Low Cost ◽

Sol Gel ◽

Alkaline Ph ◽

Modified Silica ◽

Scanning Electron

In this study, modified silica (3-Amynopropyl) triethoxysilane (APTES) synthesis and adsorption test of MB dye were performed. Silica is synthesized by sol-gel method and modified with APTES. APTES modified silica is characterized using several instruments, scanning electron microscopy (SEM), fourier transform infrared (FTIR), surface area analyzer (SAA) and UV-Vis spectrophotometer. The composite has a large surface area and has a mesoporous shape. At alkaline pH, MB dye can adsorb well. In addition, MB absorption is also maximized with the longer time of adsorption. The APTES modified silica adsorption process follows the Langmuir isotherm pattern. Thus, APTES modified silica can be used as an alternative to environmentally friendly and low-cost adsorbents.

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Development of Sustainable and Eco-Friendly Materials from Termite Hill Soil Stabilized with Cement for Low-Cost Housing in Chad

Buildings ◽

10.3390/buildings11030086 ◽

2021 ◽

Vol 11 (3) ◽

pp. 86

Author(s):

Assia Aboubakar Mahamat ◽

Numfor Linda Bih ◽

Olugbenga Ayeni ◽

Peter Azikiwe Onwualu ◽

Holmer Savastano ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Fracture Toughness ◽

Scanning Electron Microscopy ◽

Low Cost ◽

Sub Saharan Africa ◽

Ex Situ ◽

Termite Mound ◽

X Ray ◽

Scanning Electron

This paper explores the effects of cement stabilization (5, 10, 15 and 20 wt%) on the structural and mechanical properties (compressive/flexural strengths and fracture toughness) of abandoned termite mound soil. The crystal structures and crystallinity of the constituents were determined using X-ray diffraction (XRD), while the microstructure was characterized via scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The functional groups were also identified using Fourier transform infra-red spectroscopy (FTIR). The compressive/flexural strengths of the stabilized and un-stabilized termite mound soil were also studied after curing for 7, 14 and 28 days. The fracture toughness mechanism was analyzed with the aid of the R-curve method. Additionally, the underlying deformation and cracking mechanisms are elucidated via in-situ/ex-situ optical and scanning electron microscopy. The stabilized termite mound soil displayed the highest mechanical properties of 13.91 MPa, 10.25 MPa and 3.52 kPa·m1/2 for compressive strength, flexural strength and fracture toughness, respectively. Besides displaying good mechanical properties and being locally available at no cost, renewable and an eco-friendly material, the termite mound soil will contribute to lowering the cost of housing in Sub-Saharan Africa, particularly in Chad.

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Microstructural and mechanical characterization of novel AA7075 composites reinforced with rice husk ash and carbonized eggshells

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/14644207211031265 ◽

2021 ◽

pp. 146442072110312

Author(s):

Vivudh Gupta ◽

Balbir Singh ◽

RK Mishra

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Rice Husk ◽

Rice Husk Ash ◽

Low Cost ◽

Agricultural Waste ◽

Stir Casting ◽

Light Weight ◽

Weight Percentage ◽

Scanning Electron

This paper investigates microstructural and mechanical characteristics of novel AA7075 composites supplemented with agricultural waste, i.e. rice husk ash and poultry waste, i.e. carbonized eggshells. Both these wastes possess important constituents which make them potential reinforcement material for composites, and their utilization also reduces the problem of disposal to a certain extent. AA7075 composites with varying weight percentages of rice husk ash and carbonized eggshells were prepared through stir casting route. The sum of weight percentages of both reinforcements was kept constant at 5 wt.%. Composites were tested for density and different mechanical properties. Prior to these tests, composites were examined through scanning electron microscopy and energy-dispersive X-ray spectroscopy techniques, wherein uniform distribution of reinforcements was observed. Inclusion of light weight reinforcements decreased the density of composites. Among these composites, highest hardness value was shown by composite having 5 wt.% of rice husk ash with 24.47% enhancement over unreinforced AA7075. Maximum tensile strength and compression strength were exhibited by hybrid composite with 3.75 wt.% rice husk ash and 1.25 wt.% carbonized eggshells. This increment is 28.20% and 16%, respectively, over base composition. Impact strength decreased as the weight percentage of CES increased, thereby indicating brittleness in behaviour. Fractography analysis of tensile and impact test specimens was done through scanning electron microscopy to determine failure mode wherein presence of cracks, voids, dimples, debonding, etc. was observed. Hence, these light weight and low cost green AA7075 composites showed improved properties making them as an alternative as well as sustainable material for automotive and aerospace applications.

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Preparation of Activated Carbon-Based Catalyst from Candlenut Shell Impregnated with KOH for Biodiesel Production

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.777.262 ◽

2018 ◽

Vol 777 ◽

pp. 262-267 ◽

Cited By ~ 9

Author(s):

Taslim ◽

Octa Bani ◽

Iriany ◽

Novi Aryani ◽

Gapenda Sari Kaban

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Activated Carbon ◽

Heterogeneous Catalyst ◽

Potassium Hydroxide ◽

Low Cost ◽

Agricultural Waste ◽

Biodiesel Production ◽

Impregnation Time ◽

Scanning Electron

Candlenut shell is an agricultural waste which can be processed into low-cost active carbon. Activated carbon cannot be used directly as a heterogeneous catalyst in transesterification of biodiesel because of its low alkalinity, thus treatment is required. In this study, the carbonization of candlenut shells was conducted at 500°C for 4 h. The activated carbon obtained was modified by impregnation with potassium hydroxide (KOH) solution. KOH concentration used was 50g/150 ml aqua des and impregnation time was 24 h. The impregnated activated carbon was characterized by Scanning Electron Microscopy - energy dispersive spectroscopy (SEM-EDS), Fourier Transform Infrared (FTIR) spectroscopy, and was further tested as a heterogeneous catalyst for biodiesel production.

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Containerless Solidification of Eutectic PbSn Alloy Droplets in a Drop Tube

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1633 ◽

2012 ◽

Vol 727-728 ◽

pp. 1633-1637 ◽

Cited By ~ 2

Author(s):

Rafael Cardoso Toledo ◽

F.E. de Freitas ◽

Chen Y. An ◽

I.N. Bandeira

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Energy Dispersive Spectrometry ◽

Lead Concentration ◽

Low Cost ◽

Microgravity Environment ◽

Drop Tube ◽

Irregular Structures ◽

Containerless Solidification ◽

Scanning Electron

Containerless solidification of 300 to 850 µm diameter droplets of PbSn eutectic alloy was achieved by using a 3m length drop tube, which is one of the most suitable and low cost option to provide a microgravity environment on the ground. Phase morphology and composition were investigated, respectively, by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). It was found that the microstructure of the droplets depends on their sizes, where in larger diameters (>500µm) consists of both regular lamellar and irregular structures, and on other hand, for the smaller ones (<500µm) the structure is only irregular with higher lead concentration.

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