scholarly journals Two-Scale Investigation of the Retention Behavior of a Well-Graded Mixed Soil

Geosciences ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 431
Author(s):  
Osvaldo Bottiglieri ◽  
Francesco Cafaro ◽  
Federica Cotecchia
Keyword(s):  
Measurement Techniques ◽  
Research Work ◽  
Direct Determination ◽  
Clayey Sand ◽  
Infiltration Process ◽  
Compacted Soils ◽  
Combined Strategy ◽  
Adsorption Phenomena

The hydraulic characterization of mixed compacted soils is helpful for the design of earthworks subjected to drying–wetting cycles. When the mixed soil is well-graded and made of both coarse and fine fractions, its matric suction may also be due to the short-range adsorption phenomena, as for the soil investigated in this research work. A silty–clayey sand was created by a mixing procedure and experimentally investigated at two different scales. Physical modeling of an infiltration process was performed, allowing an inverse numerical analysis to infer the water retention and the hydraulic conductivity functions of the soil, whereas element testing on soil specimens allowed direct determination of the same equations. In the article, problems related to the employed suction measurement techniques have been pointed out and discussed. By this two-scale combined strategy, features of the soil hydraulic behavior, such as the wetting collapse, the shrinkage during drying, and the loop of hysteresis, were also determined.

Instrumentation for wet steam

2004 ◽  
Vol 218 (8) ◽  
pp. 811-842 ◽  
Author(s):  
A Kleitz ◽  
J M Dorey
Keyword(s):  
Liquid Phase ◽  
Liquid Film ◽  
Direct Determination ◽  
Dispersed Phase ◽  
Wet Steam ◽  
Turbine Performance ◽  
Chemical Measurements ◽  
Formation And Evolution

This paper is devoted to the measuring methods and instrumentation used in the wet-steam area for both aerodynamics measurements (pressure, temperature and velocity) taking into account the interaction between the vapour and the liquid phase, and the characterization of the liquid phase itself (dispersed phase and liquid film). The development of suitable instrumentation is an important part in understanding the formation and evolution of the liquid phase but is now more and more oriented towards practical industrial concerns, such as the direct determination of turbine performance by measuring exhaust wetness or chemical measurements relating to erosion in the transition zone inside the turbine. Emphasis has been given to techniques suitable for use in actual turbines.

Characterization of solid magnetic nanoparticles by means of solid sampling high resolution continuum source electrothermal atomic absorption spectrometry

2016 ◽  
Vol 31 (12) ◽  
pp. 2391-2398 ◽  
Author(s):  
E. Vereda Alonso ◽  
M. M. López Guerrero ◽  
M. T. Siles Cordero ◽  
J. M. Cano Pavón ◽  
A. García de Torres
Keyword(s):  
Particle Size ◽  
Magnetic Nanoparticles ◽  
Iron Concentration ◽  
Electrothermal Atomic Absorption Spectrometry ◽  
Direct Determination ◽  
Absorption Spectrometry ◽  
Solid Sampling ◽  
Continuum Source

Direct determination of iron concentration and particle size of solid MNPs using HR CS GFAAS.

scholarly journals Chemical Analysis through CL-Detection Assisted by Periodate Oxidation

2007 ◽  
Vol 2007 ◽  
pp. 1-10 ◽  
Author(s):  
Nicholaos P. Evmiridis ◽  
Athanasios G. Vlessidis ◽  
Nicholas C. Thanasoulias
Keyword(s):  
Chemical Analysis ◽  
Flow Injection ◽  
Research Work ◽  
Periodate Oxidation ◽  
Direct Determination ◽  
Good Reproducibility ◽  
Through Flow ◽  
Set Up ◽  
Simple Flow

The progress of the research work of the author and his colleagues on the field of CL-emission generated by pyrogallol oxidation and further application for the direct determination of periodate and indirect or direct determination of other compounds through flow-injection manifold/CL-detection set up is described. The instrumentation used for these studies was a simple flow-injection manifold that provides good reproducibility, coupled to a red sensitive photomultiplier that gives sensitive CL-detection. In addition, recent reports on studies and analytical methods based on CL-emission generated by periodate oxidation by other authors are included.

scholarly journals Development, in vitro and in vivo evaluations of novel lipid drug delivery system of Newbouldia laevis (P. Beauv.)

2016 ◽  
Vol 3 ◽  
pp. 184954351667344
Author(s):  
Chukwuebuka Umeyor ◽  
Emmanuel Anaka ◽  
Franklin Kenechukwu ◽  
Chinazom Agbo ◽  
Anthony Attama
Keyword(s):  
Encapsulation Efficiency ◽  
Folk Medicine ◽  
Research Work ◽  
Lipid Matrix ◽  
Solid Lipid ◽  
Development In Vitro

Newbouldia laevis (P. Beauv.) is a tropical rainforest plant used in traditional folk medicine for the treatment of malaria, cough, joint pains, stomach ache, oedema and inflammation. The main thrust of this research work was to study the analgesic/anti-nociceptive properties of N. laevis-loaded solid lipid microdispersions. N. laevis leaves were extracted using ethanol, and the extract was formulated into solid lipid microdispersions using lipid matrix comprising a rational blend of Precirol® ATO 5 and Softisan® 154. Characterization of the solid lipid microdispersions include determination of morphology, particle size, pH, thermal property, encapsulation efficiency percentage and analgesic/anti-nociceptive property. The results obtained showed that the particles were spherical with sizes ranging from 40 µm to 125 µm. The solid lipid microdispersions maintained a stable pH within the acidic region of 5–6 with insignificant variations ( p > 0.05) over a period of 90 days. Thermal analysis showed that N. laevis was entrapped in the lipid matrix used for the formulations. Solid lipid microdispersions recorded a maximum encapsulation efficiency up to 88.1%. N. laevis-loaded solid lipid microdispersions also produced good analgesic/anti-nociceptive property comparable with the standard diclofenac potassium. N. laevis-loaded solid lipid microdispersions showed good analgesic/anti-nociceptive effect and could be used in the treatment and management of pain.

scholarly journals Quantifying Mineral Liberation – A Conventional and New Automatic Sophisticated Techniques Approach

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Rudolf TOMANEC ◽  
Marina BLAGOJEV
Keyword(s):  
Prediction Accuracy ◽  
Raw Materials ◽  
Measurement Techniques ◽  
Textural Properties ◽  
Free Surfaces ◽  
Concentration Process ◽  
Mineral Liberation ◽  
Planimetric Measurements

The characterization of textural properties of minerals is closely related to the process of their respective liberation. Measurements ofmineral liberation, related to grinded ore, can be performed using optical ore microscope, by conventional, classical methods – pointcounting, linear intercepts method or planimetric measurements method (2D). Modern automatic devices and sophisticated measurement techniques (QEMSCAN/MLA) imply recording free surfaces area of mineral grains on polished sections samples in orderto determine mineral degree of liberation. Value of mineral liberation obtained over free surfaces area can be of interest to flotationconcentration, although not for gravity separation or, for example, magnetic separation. The prediction accuracy for behavior of onefeed ore during the concentration process depends on the method of measuring/recording mineral liberation. Considering raw materials with complex textural characteristics it is crucial which method will be applied for determination of mineral liberation respectingwhether for concentration process is crucial physical or chemical method.

Isolation and characterization of novel mucoadhesive biomaterial from Phoenix dactylifera

2012 ◽  
Vol 1 (8) ◽  
pp. 205-208
Author(s):  
Abhijeet Ojha ◽  
NV Satheesh Madhav
Keyword(s):  
Research Work ◽  
Pharmaceutical Journal ◽  
Phoenix Dactylifera ◽  
Isolation And Characterization ◽  
The Family ◽  
Capra Aegagrus ◽  
Cylinder Method ◽  
Bio Material

Phoenix dactylifera belongs to the family Arecaceae. The current aim of our research work is to isolate bio-material from the fruit pulp of Phoenix dactylifera and evaluate its mucoadhesivity. The bio- material was isolated by simple economical process. The isolated biomaterial was subjected for determination of solubility, colour changing point, viscosity, surface tension, pH and chemical tests. The mucoadhesivity of the biomaterial was assessed by shear stress method and rotating cylinder method using Capra aegagrus labium and intestine as mucosal substrates. The results were compared with HPMC and sodium CMC. The research study revealed that the biomaterial from Phoenix dactylifera exhibits promising inbuilt mucoadhesivity. So it can serve as a powerful natural mucoadhesant and may be used to develop mucoadhesive transmucosal drug delivery systems.DOI: http://dx.doi.org/10.3329/icpj.v1i8.11251 International Current Pharmaceutical Journal 2012, 1(8): 205-208  

scholarly journals Elastic Properties of a Polyimide Film Determined by Brillouin Scattering and Mechanical Techniques

1993 ◽  
Vol 308 ◽  
Author(s):  
R. Sai Kumar ◽  
Ivan K. Schuller ◽  
Sudha S. Kumar ◽  
A. Fartash ◽  
M. Grimsditch
Keyword(s):  
Elastic Properties ◽  
Brillouin Scattering ◽  
Direct Determination ◽  
Polyimide Film ◽  
Complete Characterization ◽  
Elastic Behavior ◽  
Complete Determination ◽  
Vibrating Membrane

ABSTRACTWe discuss here the complete determination of the elastic properties of a polyimide film using two experimental techniques. One technique employs the polymer film as a vibrating membrane and allows a direct determination of the ’macroscopic’ biaxial modulus. Brillouin scattering, which measures the elastic properties on a ∼ 100 μ scale, allows for a complete characterization of the elastic behavior. The results obtained by the two techniques are in agreement within the reported error bars.

Cryomicroscopy of low-Tg latex particles via freeze drying

1993 ◽  
Vol 51 ◽  
pp. 1198-1199
Author(s):  
J. R. Reffner
Keyword(s):  
Electron Microscopy ◽  
Freeze Drying ◽  
Room Temperature ◽  
Film Formation ◽  
Direct Determination ◽  
Particle Morphology ◽  
Latex Particles ◽  
Transmission Electron

Transmission Electron Microscopy (TEM) is a powerful tool for investigating the structure of latex particles. However, examining low Tg (glass transision, Tg < room temperature) latex particles requires special techniques due to the significant deformation which occurs if the particles are dispersed onto a substrate at room temperature. Here a freeze drying (FD) technique is presented which permits individual emulsion particles, including stained particles, to be examined in a manner that minimizes deformation by maintaining the particles at temperatures below Tg.Typically, particle morphology is determined from images of individual latex particles dispersed onto a supporting ultra-thin substrate or from images of ultra-microtomed sections of films cast from the latex. Examining particles dispersed onto a substrate is often advantageous, allowing direct determination of particle shape and characterization of the morphology prior to the film formation process. Although low Tg materials can be examined using this technique, information about the size, shape and morphology of phase separated domains can be obscured by the deformation which occurs when the particles are examined at room temperature.

Interactions in a Miscible Polymer Blend

1988 ◽  
Vol 61 (5) ◽  
pp. 866-878 ◽  
Author(s):  
C. M. Roland
Keyword(s):  
Small Angle Neutron Scattering ◽  
Main Chain ◽  
Direct Determination ◽  
Polymer Mixtures ◽  
Cohesive Energy Density ◽  
Network Properties ◽  
The Subject ◽  
Vinyl Group

Abstract Characterization of blends of atactic poly(vinylethylene) with cis-1,4-poly-isoprene provides unique insights into the factors governing the properties of polymer mixtures. While studies of polymer blends have heretofore focussed on systems in which chemical reaction between the components enabled miscibility, any properties arising from the blending of PVE with PIP are not a result of greater cohesive energy density or densification. It is also interesting to consider the different crosslinking reactivity of the main-chain unsaturation in PIP versus that of the pendant vinyl group of PVE, which can give rise to interesting network properties. These will be the subject of a subsequent communication. While it is clear that the Flory interaction parameter for these blends must be non-negative, direct determination of its magnitude is best accomplished through measurement of small-angle neutron scattering. Currently deuterated polybutadienes of varying microstructure are being synthesized to enable such experiments to be carried out, and thereby allow the effect of vinyl level on the miscibility and phase behavior to be quantified.

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