scholarly journals Резонатор лазера с интерференционно-поляризационным фильтром на основе фазовых интерферометров

2019 ◽  
Vol 126 (4) ◽  
pp. 458
Author(s):  
А.А. Ковалев

AbstractIt is proposed to use the phase properties of a reflective interferometer upon oblique incidence for spectral selection in lasers. The effect is achieved due to the difference in phases of waves having different polarization and reflected from the reflective interferometer. A simple version in which the wave is incident at the Brewster angle on the reflective interferometer in the form of a plate with a single totally reflecting face is considered for several materials of the plate. It is shown that one such element can replace several plates of Lyot-type filters. A cavity with two reflective interferometers has been calculated; in this cavity, one can multiply increase the selectivity. A version of a cavity with a reflective interferometer in the form of a thin-layer coating is considered; for this cavity, a mechanism for a twofold increase in the free dispersion region due to inclusion of a metal layer into the coating is proposed. Results of calculating a specific device for a wavelength of 0.6 μm are presented.

1892 ◽  
Vol s2-33 (130) ◽  
pp. 313-324
Author(s):  
ASAJIRO OKA ◽  
ARTHUR WILLEY

Sarcodidemnoides misakiense, Oka and Willey. Generic Characters.--Colony (or cormus) forming very thick lobose masses, laterally compressed; sessile, but not encrusting. Excurrent orifices placed on the tips of the knoll-like prominences. Ascidiozooids very numerous, not arranged in systems; branchial sac with four rows of stigmata; canal system complicated, differentiated into peripheral and central portions. Specific Characters.--Atrial apertures of Ascidiozooids simple pores without teeth or languet; spicules fairly abundant, extremely delicate, confined to a thin layer near surface of test. Test gelatinous, containing numerous bladder-cells, crystals, fusiform cells, and pigment concretions. Stomach of Ascidiozooids vertically placed; surface of attachment of colony narrower than the free portion. Colour, brilliant red. Habitat.--Moroiso, Japan, between the tide-marks. N.B.--Since the above was written I have seen for the first time the exhaustive work of Fernand Lahille, entitled ‘Recherches sur les Tuniciers des côtes de France,' Toulouse, 1890. Lahille devotes considerable attention to what have been spoken of above as tentacle-like processes of the larva, figures them in many larvæ, and gives an excellent figure of the metamorphosing larva of Styela glomerata. He gives an opinion as to their significance which I cannot entirely endorse in the light of my own researches on the "Postembryonic development of Styela," commenced last August at Plymouth. However, I hope to return to this question on a future occasion. Lahille raises an objection to von Drasche's genus Didemnoides on the ground that the thickness of the cormus is not an anatomical character, and that the distinction between thick and thin colonies is a purely subjective one. There is no doubt some truth in this; but the difference between a compound Ascidian which possesses, say, a very few spicules, and one which possesses none at all, would appear to be no more fundamental than that between a colony whose mode of growth resulted in the production of a fleshy mass and one which grew in the form of a thin leathery crust. As stated above, von Drasche intends by Didemnoides a fleshy form of Leptoclinum, the test containing spicules, and the Ascidiozooids having four rows of stigmata in the branchial sac. Lahille, on the contrary,applies the name Didemnoides to those Didemnidse which are characterised by the absence of spicules, and the possession of three rows of stigmata in the branchial sac. The compound Ascidian which we have described above has spicules in the test, and four rows of stigmata in the branchial sac. But as it would be too absurd to call the new form "Sarcoleptoclinum," we shall persist in regarding the genus Didemnoides from the point of view of von Drasche.--A. W.


Author(s):  
K V Plakhotnikov ◽  
O I Demina ◽  
O I Bondarenko ◽  
I A Plakhotnikova ◽  
S V Miroshnichenko

Food Control ◽  
2021 ◽  
Vol 120 ◽  
pp. 107446 ◽  
Author(s):  
Julie Chanut ◽  
Jean-Pierre Bellat ◽  
Régis D. Gougeon ◽  
Thomas Karbowiak

2019 ◽  
Vol 946 ◽  
pp. 253-257 ◽  
Author(s):  
Alexey Stolyarov ◽  
Guzel Kamalova ◽  
Marina Polyakova

Drawing is characterized by non-uniform character of plastic deformation, which is transferred from the die to the processed wire. Such impact causes specific change of wire microstructure. In the surface area the thin layer with highly deformed grains is observed. It is important to measure the thickness of this thin layer. For this purpose it is proposed in this paper to use the value of coefficient of anisotropy, which is calculated as the ratio of mean quantity of phase particles, crossed by secant line perpendicular to deformation axis on the unit of secant line length to the mean quantity of phase particles, crossed by secant line parallel to deformation axis on the unit of secant line length. Distribution of coefficient of anisotropy, both for low and high carbon steel wire after drawing, was obtained by Thixomet PRO software. It made it possible to calculate the thickness of highly deformed area automatically taking into consideration the difference of steels microstructure.


Geophysics ◽  
2004 ◽  
Vol 69 (4) ◽  
pp. 968-977 ◽  
Author(s):  
Andrey V. Lebedev ◽  
Igor A. Beresnev

A model of nonlinearity of the contact between the vibrator baseplate and the ground is proposed to describe the distortion of vibroseis signals in the near‐field. A thin layer between the baseplate and the soil exhibits a strong nonlinear response because of the difference in its rigidity between the compression and tension phases. The model allows for a quantitative description of the transmission of seismic energy into the ground, including the observed harmonic distortion. However, the contact nonlinearity does not lead to the dependence of wave traveltimes on the amplitude of the force applied to the ground. This fact can be used in field observations to localize the source of the observed harmonic distortion.


Author(s):  
Sten Öhman ◽  
Jan Ernerudh ◽  
Pia Forsberg ◽  
Magnus Roberg ◽  
Magnus Vrethem

Immunoglobulin M (IgM) has a very low concentration in cerebrospinal fluid (CSF) compared with serum, and therefore determinations of IgM in CSF are highly sensitive to pre-analytical errors caused by contamination with serum or interstitial fluid. Capillary attraction causes a thin layer of liquid containing serum proteins to be formed inside a conventional (Quincke) needle during penetration of tissue. To investigate this source of pre-analytical error, 35 patients had lumbar punctures using a 22 G atraumatic (Sprotte) or 25 G conventional (Quincke) needle according to a randomized scheme, and the IgM concentrations in CSF and serum were determined. The CSF IgM concentrations for samples taken with a Sprotte needle were significantly lower than those taken with a Quincke needle ( P < 0·05), whereas the corresponding serum IgM concentrations and CSF erythrocyte counts did not differ significantly. The difference indicates that CSF IgM concentrations determined after conventional sampling may be falsely increased by contamination. We conclude that IgM concentrations in CSF samples taken with the atraumatic technique are more accurate, and recommend the use of this technique when CSF IgM is to be determined.


1970 ◽  
Vol 48 (11) ◽  
pp. 751-757 ◽  
Author(s):  
M. Hidiroglou ◽  
K. J. Jenkins ◽  
J. R. Lessard ◽  
E. Borowsky

The metabolism of a single dose of 3H-DL-α-tocopherol was studied in 16 sheep fed a dystrophy-producing hay alone or supplemented with cod liver oil. During the experimental period, which lasted for 5 days after the radioisotope dosing, radioactivity was higher in the rumen liquor of cod liver oil fed sheep than in those which received only hay. Significantly lower levels of radioactivity were found in the non-saponifiable material of various tissues of cod liver oil fed sheep than in the corresponding tissues of the unsupplemented animals. By means of column chromatography, thin layer chromatography, and radioautography the bulk of liver radioactivity was identified as unchanged α-tocopherol. Possible reasons for the difference in tissue radioactivity levels between cod liver oil fed and unsupplemented sheep are discussed.


Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3380 ◽  
Author(s):  
Bofang Zhou ◽  
Zhichen Zeng ◽  
Yuchen Cai ◽  
Keqin Feng

Zr-Cu filler metal is proposed for SiC ceramic under special working conditions, as a novel type of the active filler metal, the difference of physical and chemical properties between SiC ceramic and Zr-Cu filler metal leads to greater residual stress in the joint, which affects the mechanical properties of brazing SiC ceramic joint. Based on the finite element method (FEM) simulation, the residual stress of the joint is simulated to guide the design of Zr-based filler metal and formulation of brazing process. The residual stress distribution of SiC ceramic joints brazed at 1200 °C with different thickness of the filler metal and cooling rate is simulated by ANSYS software. The simulation results of the residual stress are verified by brazing experiments and XRD measurements. The results show that the simulated residual stress of the joint is mainly axial compressive stress. The axial compressive stresses are the lowest when the filler metal thickness is 0.1 mm and the cooling rate is 2 °C /min, and increase with the increase of the filler metal layer thickness and cooling rate. The shear strength of the brazed SiC ceramic joint that achieves the highest with 2 °C /min is about 72 MPa, and then decreases with the increase of cooling rate. The experimental test of residual stress in different locations of the brazed SiC ceramic joint basically coincide with the FEM simulation.


2020 ◽  
Vol 5 (8) ◽  
pp. 2401-2407 ◽  
Author(s):  
Lei Tian ◽  
Yuxiu Sun ◽  
Hongliang Huang ◽  
Xiangyu Guo ◽  
Zhihua Qiao ◽  
...  

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