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Author(s):  
I. J. Akinruli ◽  
F. T. Akinruli

Introduction: Despite the efforts of Governments and non-governmental organizations in sponsoring ceramic water purifier (CWP) filter project across the globe, some rural communities in Ekiti State, Nigeria are yet to benefit from it. One of the major technical difficulties hindering the making of CWP filter cells in many places was the adaptation to the sand, clay and sawdust mixture necessary to obtain the correct filter properties. Aim: In this study, some salient properties of clay from orudi, arade and oturo deposits at Isan Ekiti were assessed in the light of their usefulness for making the ceramic water filter cells. Methodology: The particle size distribution analysis and consistency tests were carried out on the crude clay. Also the shrinkage, effects of percentage constituents of burnout on porosity, filtration rate and quality of filtrate were measured, using standard methods. Results: Results show that arade has the appropriate technical properties for making the filter cell. The chosen clay sample has its deposit less than 2 kilometers to the point of making. About 56% of its particles are less than 0.075mm equivalent spherical diameter (ESD). A composition of ratio 50:50 by volume mixture of clay to sawdust has the   porosity of 54. 55% while that of ratio 40:60 is 55.56%. Samples made of these batches were capable of reducing the water turbidity Neflometric Turbidity Unit (NTU) of contaminated water by 95%.  The 50:50 samples have the higher capacity of reducing total coliform count by 50.28% as against 25.07% for 40:60 samples. Conclusion: Given appropriate facilities and training, with the abundant clay at arade deposit, the pottery center is a place where CWP filter cell factory could be established.


2021 ◽  
Vol 23 (6) ◽  
Author(s):  
M. Meischein ◽  
A. Ludwig

AbstractUpscaling of nanoparticle fabrication by sputtering into an ionic liquid is shown for the example of Cu. Long-time sputtering (24 h) into a large amount (50 mL) of the ionic liquid 1-butyl-3-methylimidazolium bis-(trifluoromethylsulfonyl)imide [Bmim][(Tf)2 N] yields an amount of approximately 1 g Cu nanoparticles (mean spherical diameter (2.6 ± 1.1) nm), stabilized in ionic liquid without agglomerations. Extraction of Cu nanoparticles from the stabilizing ionic liquid was performed with the capping agent hexadecylamine. Extracted particles could be redispersed in other solvents, thus enabling applications of sputtered nanoparticles beyond ionic liquids.


2021 ◽  
Vol 11 (11) ◽  
pp. 5150
Author(s):  
Ming Z. Fan ◽  
Weijun Wang ◽  
Laurence Cheng ◽  
Jiali Chen ◽  
Wenyi Fan ◽  
...  

Biomass includes cellulose, hemicelluloses, pectin and lignin; constitutes the components of dietary fibre of plant and alge origins in animals and humans; and can potentially provide inexhaustible basic monomer compounds for developing sustainable biofuels and biomaterials for the world. Development of efficacious cellulases is the key to unlock the biomass polymer and unleash its potential applications in society. Upon reviewing the current literature of cellulase research, two characterized and/or engineered glycosyl hydrolase family-5 (GH5) cellulases have displayed unique properties of processive endoglucanases, including GH5-tCel5A1 that was engineered and was originally identified via targeted genome sequencing of the extremely thermophilic Thermotoga maritima and GH5-p4818Cel5_2A that was screened out of the porcine hindgut microbial metagenomic expression library. Both GH5-tCel5A1 and GH5-p4818_2A have been characterized as having small molecular weights with an estimated spherical diameter at or < 4.6 nm; being monomodular without a required carbohydrate-binding domain; and acting as processive β-1,4-endoglucanases. These two unique GH5-tCel5A1 and GH5-p4818_2A processive endocellulases are active in hydrolyzing natural crystalline and pre-treated cellulosic substrates and have multi-functionality towards several hemicelluloses including β-glucans, xylan, xylogulcans, mannans, galactomannans and glucomannans. Therefore, these two multifunctional and monomodular GH5-tCel5A1 and GH5-p4818_2A endocellulases already have promising structural and functional properties for further optimization and industrial applications.


2021 ◽  
Author(s):  
Michael Meischein ◽  
Alfred Ludwig

Abstract Up-scaling of nanoparticle fabrication by sputtering into an ionic liquid is shown for the example of Cu. Long-time sputtering (24 h) into a large amount (50 mL) of the ionic liquid 1-butyl-3-methylimidazolium bis-(trifluoromethylsulfonyl)imide [Bmim][(Tf)2N] yields an amount of approximately 1 g Cu nanoparticles (mean spherical diameter (2.6 ± 1.1) nm), stabilized in ionic liquid without agglomerations. Extraction of Cu nanoparticles from the stabilizing ionic liquid was performed with the capping agent hexadecylamine. Extracted particles could be redispersed in other solvents, thus enabling applications of sputtered nanoparticles beyond ionic liquids.


2021 ◽  
Author(s):  
Haibin Chen ◽  
Tianchong Xie ◽  
Jiashuang Feng ◽  
Xiongxing Zhang ◽  
Wei Wang ◽  
...  

AbstractA fiber-optic temperature sensor based on fiber tip polystyrene microsphere is proposed. The sensor structure can be formed simply by placing and fixing a polystyrene microsphere on the center of an optical fiber tip. Since polystyrene has a much larger thermal expansivity, the structure can be used for high-sensitive temperature measurement. By the illuminating of the sensor with a broadband light source and through the optical Fabry-Perot interference between the front and back surfaces of the polystyrene microsphere, the optical phase difference (OPD) or wavelength shift can be used for the extraction of temperature. Temperature measurement experiment shows that, using a fiber probe polystyrene microsphere temperature sensor with a spherical diameter of about 91.7 µm, a high OPD-temperature sensitivity of about −0.617 96 nm/°C and a good linearity of 0.991 6 were achieved in a temperature range of 20°C–70°C.


Author(s):  
Laura Shedd ◽  
Matthew R. Kumjian ◽  
Ian Giammanco ◽  
Tanya Brown-Giammanco ◽  
B. Ross Maiden

AbstractHailstone growth results in a variety of hailstone shapes. These shapes hold implications for modeling of hail processes, hailstone fall behaviors including fall speeds, and remote sensing signatures of hail. This study is an in-depth analysis of natural hailstone shapes, using a large dataset of hailstones collected in the field over a 6-year period. These data come from manual measurements with digital calipers and three-dimensional infrared laser scans. Hailstones tend to have an ellipsoidal geometry with minor-to-major axis ratios ranging from 0.4 to 0.8, and intermediate-to-major axis ratios between 0.8 and 1.0. These suggest hailstones are better represented as tri-axial ellipsoids as opposed to spheres or spheroids, which is commonly assumed. The laser scans allow for precise sphericity measurements, for the first time. Hailstones become increasingly nonspherical with increasing maximum dimension, with a typical range of sphericity values of 0.57 to 0.99. These sphericity values were used to estimate the drag coefficient, which was found to have a typical range of 0.5 to over 0.9. Hailstone maximum dimension tends to be 20–50% larger than the equivalent volume spherical diameter. As a step towards understanding and quantifying hailstone shapes, this study may aid in better parameterizations of hail in models and remote sensing hail detection and sizing algorithms.


2020 ◽  
Author(s):  
Emrah Akkoyun ◽  
Hamidreza Gharahi ◽  
Sebastian T. Kwon ◽  
Byron A. Zambrano ◽  
Akshay Rao ◽  
...  

AbstractObjectiveThe maximum diameter measurement of an abdominal aortic aneurysm (AAA), which depends on orthogonal and axial cross-sections or maximally inscribed spheres within the AAA, plays a significant role in the clinical decision making process. This study aims to build a large dataset of morphological parameters from longitudinal CT scans and analyze their correlations. Furthermore, this work explores the existence of a “master curve” of AAA growth, and tests which parameters serve to enhance its predictability for clinical use.Methods106 CT scan images from 25 Korean AAA patients were retrospectively obtained. We subsequently computed morphological parameters, growth rates, and pair-wise correlations, and attempted to enhance the predictability of the growth for high-risk aneurysms using non-linear curve fitting and least-square minimization.ResultsAn exponential AAA growth model was fitted to the maximum spherical diameter, as the best representative of the growth among all parameters (r-square: 0.985) and correctly predicted to 74 of 79 scans based on a 95% confidence interval. AAA volume expansion rateswere highly correlated (r=0.80) with thrombus accumulation rates.ConclusionsThe exponential growth model using spherical diameter provides useful information about progression of aneurysm size and enables AAA growth rate extrapolation during a given surveillance period.


Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2165
Author(s):  
Monica Boffito ◽  
Rossella Laurano ◽  
Dimitra Giasafaki ◽  
Theodore Steriotis ◽  
Athanasios Papadopoulos ◽  
...  

The high drug loading capacity, cytocompatibility and easy functionalization of ordered mesoporous carbons (OMCs) make them attractive nanocarriers to treat several pathologies. OMCs’ efficiency could be further increased by embedding them into a hydrogel phase for an in loco prolonged drug release. In this work, OMCs were embedded into injectable thermosensitive hydrogels. In detail, rod-like (diameter ca. 250 nm, length ca. 700 nm) and spherical (diameter approximately 120 nm) OMCs were synthesized by nanocasting selected templates and loaded with ibuprofen through a melt infiltration method to achieve complete filling of their pores (100% loading yield). In parallel, an amphiphilic Poloxamer® 407-based poly(ether urethane) was synthesized (Mn¯ 72 kDa) and solubilized at 15 and 20% w/v concentration in saline solution to design thermosensitive hydrogels. OMC incorporation into the hydrogels (10 mg/mL concentration) did not negatively affect their gelation potential. Hybrid systems successfully released ibuprofen at a slower rate compared to control gels (gels embedding ibuprofen as such), but with no significant differences between rod-like and spherical OMC-loaded gels. OMCs can thus work as effective drug reservoirs that progressively release their payload over time and also upon encapsulation in a hydrogel phase, thus opening the way to their application to treat many different pathological states (e.g., as topical medications).


2020 ◽  
Vol 14 (2) ◽  
pp. 6610-6624 ◽  
Author(s):  
Om Parkash Verma ◽  
Arvind Kumar ◽  
Basant Singh Sikarwar

Transportation of solids with water as a carrier in the form of slurry through long length pipelines is widely used by many industries and power plants. The transportation of slurry through vertical pipeline is a challenging task and require modification to overcome the pressure loss and power consumption requirements. In this perspective, numerical simulation of three-dimensional horizontal slurry pipeline (HSPL) and vertical slurry pipeline (VSPL) carrying glass beads solid particulates of spherical diameter 440 µm and density 2,470 kg/m3 is carried out. The 3D computational model for horizontal and vertical slurry pipeline is developed for a pipe of 0.0549 m diameter and analyzed in available commercial software ANSYS Fluent 16. The simulation is conducted by using Eulerian multiphase model with RNG k-ɛ turbulence closure at solid concentration range 10 – 20% (by volume) for mean flow velocities ranging from 1-4 ms-1. It is found that the pressure drop rises for both HSPL and VSPL with escalation in mean flow velocity and solid concentration. The predicted pressure drop in VSPL is found to follow the same pattern as with HSPL but higher in magnitude for all chosen velocity and solid concentration range. The obtained results of predicted pressure drop in HSPL are validated with the available experimental data in the literature. A parametric study is conducted with the aim of visualizing and understanding the slurry flow behavior in HSPL and VSPL. Finally, the results of solid concentration contour, velocity contour, solid concentration profiles, velocity profiles and pressure drop are predicted for both the slurry pipelines.


Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 883
Author(s):  
Andreas Reul ◽  
Elena Martín-Clemente ◽  
Ignacio J. Melero-Jiménez ◽  
Elena Bañares-España ◽  
Antonio Flores-Moya ◽  
...  

A seasonal cycle of sulfide, nitrate, phosphate, ammonium, chlorophyll a (Chl a) and Oscillatoria sp. abundance (<100 μm), as well as the relative contribution of taxonomic phytoplanktonic groups (cyanobacteria, green algae, cryptomonads, diatoms and dinoflagellates) to total Chl a were measured by fluorometric measurements at La Hedionda sulfide-rich spa (southern Spain). Fluorometry determined that cyanobacteria Chl a concentration correlated positively with the abundance of Oscillatoria sp. Aggregates at 45–100 μm equivalent spherical diameter (ESD) and was used as an indicator of Oscillatoria sp. Abundance, including for aggregates <45 and >100μm (ESD). In addition, air temperature, radiation and precipitation were downloaded from meteorological databases. In agreement with the meteorological annual cycle observed in air temperature, radiation and precipitation, sulfide concentration at La Hedionda Spa shows an annual cycle with concentrations around 40 μM in winter and up to 200 μM in the dry summer period. Phytoplankton composition was dominated by cyanobacteria (mainly Oscillatoria sp.), but other groups were also represented (green algae, cryptomonads, diatoms and dinoflagellates), although they remained constant throughout the year (median Chl a < 0.2 μg L−1). Cyanobacteria, in contrast, showed an annual cycle with a significantly higher median in summer (Chl a = 1.6 μg L−1) than in winter (Chl a = 0.4 μg L−1). No linear relationship between nutrients and cyanobacteria concentration was observed, but an optimum curve of cyanobacteria concentration to sulfide concentration was fitted through a general additive model (GAM). The four-fold increase of cyanobacteria concentration under exposition of an elevated sulfide concentration can be due to higher growth rates at elevated sulfide concentrations reported for an Oscillatoria sp. strain isolated during the same annual cycle at La Hedionda and we suggest that the selective agent, sulfide, positively triggers Oscillatoria sp. proliferation in summer. According to our findings, the Oscillatoria sp. population of La Hedionda not only is sulfide-resistant, but requires sulfide in its optimal niche.


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