scholarly journals Specific Features of Microwave Methods for Dusty Plasma Diagnostics. I. Dielectric Permittivity, Refractive and Absorption Indices

2019 ◽  
Vol 64 (5) ◽  
pp. 380
Author(s):  
Yu. V. Kovtun ◽  
A. I. Skibenko ◽  
E. I. Skibenko ◽  
Ye. V. Siusko
Keyword(s):  
Dielectric Permittivity ◽  
Dusty Plasma ◽  
Plasma Diagnostics ◽  
Collision Frequency ◽  
Frequency Parameter ◽  
The Other ◽  
Dust Particles ◽  
Plasma Ions ◽  
Free Plasma

Two widely used approaches for the determination of the refractive, n, and absorption, ϰ, indices of a dusty plasma have been analyzed. In one of them, the expressions for n and ϰ obtained for a dust-free plasma are used, but the collisions of plasma ions with dust particles are taken into account by means of the collision frequency parameter. In the other approach, the characteristic charging frequency for dust particles is additionally introduced.

scholarly journals Study of the Propagation Characteristics of Terahertz Waves in a Collisional and Inhomogeneous Dusty Plasma with a Ceramic Substrate and Oblique Angle of Incidence

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Qingwen Rao ◽  
Guanjun Xu ◽  
Pengfei Wang ◽  
Zhengqi Zheng
Keyword(s):  
Electron Density ◽  
Dusty Plasma ◽  
Collision Frequency ◽  
Incident Angle ◽  
Ceramic Substrate ◽  
Dust Particles ◽  
Angle Of Incidence ◽  
Oblique Angle ◽  
Terahertz Waves ◽  
Thz Wave

In this paper, the propagation properties of a terahertz (THz) wave in a collisional and inhomogeneous dusty plasma with a ceramic substrate and oblique angle of incidence are studied using the scattering matrix method. The influence of the various corresponding parameters, such as the frequency of the THz wave, angle of incidence, electron density, radius and density of the dust particles, and the collision frequency, on the absorbance and transmittance is calculated. The results of the simulation indicate that an increase in the wave frequency increases the transmittance and decreases the absorbance. Moreover, the absorbance of a THz wave in a dusty plasma with a ceramic substrate increases with an increase in the incident angle, maximum electron density, coefficient of steepness, density and radius of the dust particles, and collision frequency. These results provide an important theoretical basis for the problem of communication blackout between ground and spacecraft.

scholarly journals Methods for the Determination of Plasmin, Antiplasmin and Plasminogen by Means of the Substrate S-2251

1977 ◽  
Author(s):  
P. Friberger ◽  
M. Knös ◽  
S. Gustavsson ◽  
L. Aurell ◽  
G. Claeson
Keyword(s):  
Incubation Time ◽  
Tris Buffer ◽  
The Other ◽  
Optimal Conditions ◽  
Peptide Substrate ◽  
Substrate Saturation ◽  
Optimal Medium ◽  
Free Plasma

The chromogenic peptide substrate H-D-Val-L-Leu-L-Lys-pNA (S-2251) has been chosen from a series of potent plasmin substrates. It is a highly specific and sensitive substrate towards plasmin (Km 2.5·10-4 mol/1, V 0.5·10-6 mol/min CTA-U) and its solubility in tris buffer (1·10-2 mol/1)is sufficient to obtain substrate saturation. Tris buffer pH 7.4 and I 0.15 serves as an optimal medium for the determination of plasmin. In this buffer, antiplasmins in plasma have been determined by using 0.05 CU of plasmin and 20 ul of plasma. At least two inhibitors have been found. One fast (<15 sec. incubation time) and the other(s)slow (5 min. incubation time).The substrate has also been used for plasminogen determinations after activation of 10 ul of plasma with UK (500 Ploug-U) or an excess (40 times) of SK. It was found that neither plasminogen free plasma (100% antiplasmin activity) nor an excess (>1000 times) of SBTI inhibited the substrate activity of the SK activated plasminogen. Optimal conditions for the SK-activated plasminogen was tris buffer pH 7.4, I 0.05. Km = 2.4.10-4 mol/1 for both purified plasminogen and plasma and V = 1.10-4 mol/min.CU or 3.10-6 mol/min-ml plasma.

Dust-Trash Removal by the SRRC Tuft-To-Yarn Processing System

1979 ◽  
Vol 101 (2) ◽  
pp. 197-204
Author(s):  
J. I. Kotter ◽  
D. P. Thibodeaux
Keyword(s):  
Processing System ◽  
The Other ◽  
Dust Particles ◽  
Cotton Fibers ◽  
Aerodynamic Diameter ◽  
Fine Dust ◽  
Cleaning Efficiency

A detailed study of the quality and quantity of fine dust and trash removed from cotton fibers by the SRRC Tuft-to-Yarn system in its various stages of processing is presented. Collection of fine dust and trash was accomplished by isokinetic sampling from the respective pneumatic systems of the mini-condensers and OE spinners. An impaction-type precutter permitted classifying dust particles from the sampled air into two fractions, one greater than 15 μm aerodynamic diameter and the other less. Three grades of cotton, SM, SLM, and SGO, were used in the study which also included a determination of the cleaning efficiency of each of the processing stages, based on trash content and amounts removed as measured by the Shirley analyzer. A comparison is made between the proportion of fine dust removed by the system and the residues of dust/trash found in conventional OE spinner rotors.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

Procedures for the Quantitative Determination of Autoprothrombin C

1962 ◽  
Vol 08 (03) ◽  
pp. 434-441 ◽  
Author(s):  
Edmond R Cole ◽  
Ewa Marciniak ◽  
Walter H Seegers
Keyword(s):  
Quantitative Determination ◽  
Plasma Sample ◽  
Quantitative Measure ◽  
The Other ◽  
Clotting Time ◽  
Bovine Plasma ◽  
Autoprothrombin C

SummaryTwo quantitative procedures for autoprothrombin C are described. In one of these purified prothrombin is used as a substrate, and the activity of autoprothrombin C can be measured even if thrombin is in the preparation. In this procedure a reaction mixture is used wherein the thrombin titer which develops in 20 minutes is proportional to the autoprothrombin C in the reaction mixture. A unit is defined as the amount which will generate 70 units of thrombin in the standardized reaction mixture. In the other method thrombin interferes with the result, because a standard bovine plasma sample is recalcified and the clotting time is noted. Autoprothrombin C shortens the clotting time, and the extent of this is a quantitative measure of autoprothrombin C activity.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

scholarly journals Evaluation of Marblewood Dust’s (Marmaroxylon racemosum) Effect on Ignition Risk

2021 ◽  
Vol 11 (15) ◽  
pp. 6874
Author(s):  
Miroslava Vandličkova ◽  
Iveta Markova ◽  
Katarina Holla ◽  
Stanislava Gašpercová
Keyword(s):  
Particle Size ◽  
Dust Particles ◽  
Wood Dust ◽  
Sieve Analysis ◽  
Granulometric Analysis ◽  
Analysis Measurement ◽  
Risk Research ◽  
Minimum Ignition Temperature ◽  
The Impact

The paper deals with the selected characteristics, such as moisture, average bulk density, and fraction size, of tropical marblewood dust (Marmaroxylon racemosum) that influence its ignition risk. Research was focused on sieve analysis, granulometric analysis, measurement of moisture level in the dust, and determination of the minimum ignition temperatures of airborne tropical dust and dust layers. Samples were prepared using a Makita 9556CR 1400W grinder and K36 sandpaper for the purpose of selecting the percentages of the various fractions (<63, 63, 71, 100, 200, 315, 500 μm). The samples were sized on an automatic vibratory sieve machine Retsch AS 200. More than 65% of the particles were determined to be under 100 μm. The focus was on microfractions of tropical wood dust (particles with a diameter of ≤100 µm) and on the impact assessment of particle size (particle size <100 µm) on the minimum ignition temperatures of airborne tropical dust and dust layers. The minimum ignition temperature of airborne marblewood dust decreased with the particle size to the level of 400 °C (particle size 63 μm).

Determination of the Number of Conserved Chromosomal Segments Between Species

Genetics ◽  
2001 ◽  
Vol 157 (3) ◽  
pp. 1387-1395 ◽  
Author(s):  
Sudhir Kumar ◽  
Sudhindra R Gadagkar ◽  
Alan Filipski ◽  
Xun Gu
Keyword(s):  
Statistical Approach ◽  
Common Ancestor ◽  
Chromosomal Rearrangements ◽  
Structural Similarity ◽  
The Other ◽  
Segment Length ◽  
Human Genomes ◽  
Genomic Divergence ◽  
Human And Mouse

AbstractGenomic divergence between species can be quantified in terms of the number of chromosomal rearrangements that have occurred in the respective genomes following their divergence from a common ancestor. These rearrangements disrupt the structural similarity between genomes, with each rearrangement producing additional, albeit shorter, conserved segments. Here we propose a simple statistical approach on the basis of the distribution of the number of markers in contiguous sets of autosomal markers (CSAMs) to estimate the number of conserved segments. CSAM identification requires information on the relative locations of orthologous markers in one genome and only the chromosome number on which each marker resides in the other genome. We propose a simple mathematical model that can account for the effect of the nonuniformity of the breakpoints and markers on the observed distribution of the number of markers in different conserved segments. Computer simulations show that the number of CSAMs increases linearly with the number of chromosomal rearrangements under a variety of conditions. Using the CSAM approach, the estimate of the number of conserved segments between human and mouse genomes is 529 ± 84, with a mean conserved segment length of 2.8 cM. This length is &lt;40% of that currently accepted for human and mouse genomes. This means that the mouse and human genomes have diverged at a rate of ∼1.15 rearrangements per million years. By contrast, mouse and rat are diverging at a rate of only ∼0.74 rearrangements per million years.

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