scholarly journals Reflection of sound pulses from an inhomogeneous bubble medium

2021 ◽  
Vol 2057 (1) ◽  
pp. 012032
Author(s):  
I A Ogorodnikov
Keyword(s):  
Absorption Band ◽  
Emission Spectrum ◽  
Initial Phase ◽  
Volume Concentration ◽  
Transition Radiation ◽  
Spectral Characteristics ◽  
Bubble Medium ◽  
Boundary Zone ◽  
Initial Stage ◽  
Sound Pulses

Abstract The effect of changes in the volume concentration of bubbles in the boundary zone of the bubble medium on the nature of reflection and radiation of the excited bubble medium is studied. The spectral characteristics of the radiation of a bubble medium are obtained at the initial stage of transition radiation and at large times when the radiation is stationary. It is shown that in the initial phase the emission spectrum is broadband and is located in the absorption band of the bubble medium, and at large times the emission spectrum is located outside this band.

scholarly journals The Impacts of Various Media on the Electronic Spectrum of Aniline Violet

2021 ◽  
Vol 2 (24) ◽  
pp. 28-55
Author(s):  
Sokaina Hemdan ◽  
◽  
Asma Al Jebaly ◽  
Fatma Ali
Keyword(s):  
Hydrogen Bonding ◽  
Absorption Band ◽  
Dissociation Constant ◽  
Relative Permittivity ◽  
Spectral Characteristics ◽  
Solvent Polarity ◽  
Isosbestic Point ◽  
Solvent Interactions ◽  
Solvent Parameters ◽  
The Impact

The solvent impact can be decided by Solvent polarity scales, a solvatochromic parameter that has a distinctive position of UV-Visible absorption band within the extend between 250 and 700 nm. The spectral characteristics of Aniline Violet in several solvents at room temperature were analyzed which is that the point of considering the impact of solvents on the absorption spectra of this cationic dye in organic solvent of distinctive characters. The solvent impacts on the wavenumber of the absorption band maxima (max) were talked about utilizing the taking after solvent parameters, refractive index, n, relative permittivity, ε and therefore the empirical solvent polarity ET (30), (*,  and ) and (SA, SB, SP and SPd). The solute–solvent interactions were decided on the premise of multilinear solvation energy relationships concept. The fitting coefficients gotten from this analysis allowed us to estimate the contribution of each type of interactions to the total spectral shifts in solution. The set up dependences between max and the solvent parameters emphasize that the visible band of the examined molecule is influenced by both non-specific and specific solute–solvent interactions. The results appeared the solvent polarizability has major impact on the spectral shift instead of hydrogen bonding accepting ability. Catalan strategy show higher acceptable correlation than Kamlet-Taft methodology and Katritzky methodology. The dissociation constant pKa and the isosbestic point of the explored compound were shown the presence of the individual predominate ionic species was assigned by constructing distribution charts at diverse pH ranges. The results showed that the relative permittivity constant, ε, is important factor affecting on the magnitude of the dissociation constant beside the hydrogen bonding of the solvent.

scholarly journals Evaluation And Selection Of Colour Spaces For Digital Systems

2020 ◽  
pp. 86-94
Author(s):  
Vera L. Zhbanova
Keyword(s):  
Spectral Characteristics ◽  
Colorimetric Method ◽  
Digital Systems ◽  
Colour Difference ◽  
Colour Space ◽  
Digital Devices ◽  
Initial Stage ◽  
Photo Detectors ◽  
The Difference ◽  
Selection Of

The research examined the changing of colour difference by the control colours depending on the choice of colour space when working with matrix photo detector. The spectral characteristics of photo detectors from different manufacturers noticeably differ from each other and from the addition the difference in colour quality between different digital devices. A software method for studying the colour rendition of the image obtained by digital devices based on the selection of an individual colour space for each matrix photo detector is proposed. To analyze and evaluate the capabilities of the spectral characteristics of matrix photo detectors, the control colour method based on the Mansell Atlas was used. The analysis of the obtained parameters of 14 colours was carried out according to various criteria for seven colour spaces: sRGB, AdobeRGB, DCI-P3 RGB, M1N1P1, PAL / SECAM, Wide Gamut RGB, ProPhoto RGB. Also studied the influence of the choice of colour space on the change in the coordinates of the source 6,500 K. Based on the colour differences of the control colours, it is possible to choose the optimal colour space for working with a specific matrix photo detector. The latter will reduce colour distortion at the initial stage of image registration. The ways for improving the colorimetric method of control colours are proposed as applied to digital devices at the software level.

scholarly journals Exploring the Mechanism of Olfactory Recognition at the Initial Stage by Modeling the Emission Spectrum of Electron Transfer

2019 ◽  
Author(s):  
Shu Liu ◽  
Rao Fu ◽  
Guangwu Li
Keyword(s):  
Electron Transfer ◽  
Emission Spectrum ◽  
Active Sites ◽  
Isotope Effects ◽  
Emission Spectra ◽  
Initial Stage ◽  
Olfactory Sense ◽  
Bitter Almond ◽  
Deuterated Analogue ◽  
Odorant Molecule

AbstractOlfactory sense remains elusive regarding the primary reception mechanism. Some studies suggest that olfaction is a spectral sense, the olfactory event is triggered by electron transfer (ET) across the odorants at the active sites of odorant receptors (ORs). Herein we present a Donor-Bridge-Acceptor model, proposing that the ET process can be viewed as an electron hopping from the donor molecule to the odorant molecule (Bridge), then hopping off to the acceptor molecule, making the electronic state of the odorant molecule change along with vibrations (vibronic transition). The odorant specific parameter, Huang–Rhys factor can be derived from ab initio calculations, which make the simulation of ET spectra achievable. In this study, we revealed that the emission spectra (after Gaussian convolution) can be acted as odor characteristic spectra. Using the emission spectrum of ET, we were able to reasonably interpret the similar bitter-almond odors among hydrogen cyanide, benzaldehyde and nitrobenzene. In terms of isotope effects, we succeeded in explaining why subjects can easily distinguish cyclopentadecanone from its fully deuterated analogue cyclopentadecanone-d28 but not distinguishing acetophenone from acetophenone-d8.

scholarly journals EXPERIMENTAL NEPHRITIS IN RATS INDUCED BY INJECTION OF ANTI-KIDNEY SERUM

1937 ◽  
Vol 65 (4) ◽  
pp. 527-540 ◽  
Author(s):  
Joseph E. Smadel ◽  
Lee E. Farr
Keyword(s):  
Plasma Protein ◽  
Initial Phase ◽  
Urea Clearance ◽  
Chronic Type ◽  
Initial Stage ◽  
Experimental Nephritis

The glomerulonephritis induced in rats by nephrotoxin was characterized clinically during its initial phase by severe albuminuria, cylindruria, and anasarca, but not by hematuria. Rapidly fatal nephritis was produced by injecting relatively large amounts of anti-kidney serum at frequent intervals. In such cases the blood urea mounted rapidly; the urea clearance fell; and death occurred within about 2 weeks. A milder nephritis of the chronic type was induced by giving smaller quantities of anti-kidney serum in either single or divided doses. In these instances there was no immediate alteration of the urea clearance. Lipemia and plasma protein deficit appeared with the development of anasarca. The majority of rats which survived the initial stage of this experimental nephritis continued to show marked albuminuria with casts until they died or were sacrificed months later. Some of these animals showed retardation of growth and a progressive fall of the urea clearance. Terminally there developed marked retention of urea, plasma protein deficit, anemia, and hypertension.

scholarly journals Optoelectronic complex for express laser diodes lifetime prediction

2019 ◽  
Vol 220 ◽  
pp. 02002
Author(s):  
Vladimir Bliznyuk ◽  
Alexey Dolgov ◽  
Vasiliy Parshin ◽  
Alexey Rzhanov ◽  
Olga Semenova ◽  
...  
Keyword(s):  
Spectral Characteristics ◽  
Laser Diodes ◽  
Control Unit ◽  
Single Mode ◽  
Lifetime Prediction ◽  
Measurement Unit ◽  
Spectral Radiation ◽  
Single Mode Laser ◽  
Initial Stage ◽  
Input Control

This paper presents the optoelectronic complex, which provides both preparations for carrying out an express lifetime prediction of edge emitted strip single-mode laser diodes. It is shown that for this purpose the complex should consist of four operational units: an input control unit; a spectral radiation characteristics measurement unit; a laser lifetime forecasting unit and automatic processing hardware unit. The use of this complex makes it possible to predict the lifetime of a laser diode according to their spectral characteristics at the initial stage of its operation.

Nanoparticle Friction Force and Effective Viscosity of Nanosuspensions

2008 ◽  
Vol 273-276 ◽  
pp. 566-571 ◽  
Author(s):  
Valery Rudyak ◽  
A.A. Belkin ◽  
E.A. Tomilina ◽  
V.V. Egorov
Keyword(s):  
Molecular Dynamics ◽  
Friction Coefficient ◽  
Friction Force ◽  
Effective Viscosity ◽  
Volume Concentration ◽  
Massive Particle ◽  
Viscosity Coefficient ◽  
Initial Stage ◽  
Stokes Force ◽  
Dynamics Method

The transport properties of nanofluids are investigated by the molecular dynamics method. It is shown that the force acting on a nanoparticle is nonstationary, in contrast to the Stokes force. In the initial stage of relaxation, the friction force is greater than the Stokes value. Subsequently, this force decreases and reaches an asymptotic value. This value is comparable to the Stokes force only for a massive particle. A correlation for determining the friction coefficient is constructed. It is established that the effective viscosity coefficient of nanofluids depends not only on the volume concentration of nanoparticles but also on the nanoparticle mass and radius.

The first UV absorption band ofl-tryptophan is not due to two simultaneous orthogonal electronic transitions differing in the dipole moment

2016 ◽  
Vol 18 (22) ◽  
pp. 15170-15176 ◽  
Author(s):  
Javier Catalán
Keyword(s):  
Dipole Moment ◽  
Absorption Band ◽  
Emission Spectrum ◽  
Uv Absorption ◽  
Electronic Transitions ◽  
The Difference

The difference between the emission spectrum ofl-tryptophan in ethanol obtained at 113 K and at 293 K.

scholarly journals CO2 Retrieval over Clouds from the OCO Mission: Model Simulations and Error Analysis

2009 ◽  
Vol 26 (6) ◽  
pp. 1090-1104 ◽  
Author(s):  
Jérôme Vidot ◽  
Ralf Bennartz ◽  
Christopher W. O’Dell ◽  
René Preusker ◽  
Rasmus Lindstrot ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Absorption Band ◽  
Liquid Water ◽  
Spectral Characteristics ◽  
Optimal Estimation ◽  
High Spectral Resolution ◽  
Oxygen Absorption ◽  
Co2 Absorption ◽  
Mixing Ratio ◽  
Cloud Properties

Abstract Spectral characteristics of the future Orbiting Carbon Observatory (OCO) sensor, which will be launched in January 2009, were used to infer the carbon dioxide column-averaged mixing ratio over liquid water clouds over ocean by means of radiative transfer simulations and an inversion process based on optimal estimation theory. Before retrieving the carbon dioxide column-averaged mixing ratio over clouds, cloud properties such as cloud optical depth, cloud effective radius, and cloud-top pressure must be known. Cloud properties were not included in the prior in the inversion but are retrieved within the algorithm. The high spectral resolution of the OCO bands in the oxygen absorption spectral region around 0.76 μm, the weak CO2 absorption band around 1.61 μm, and the strong CO2 absorption band around 2.06 μm were used. The retrieval of all parameters relied on an optimal estimation technique that allows an objective selection of the channels needed to reach OCO’s requirement accuracy. The errors due to the radiometric noise, uncertainties in temperature profile, surface pressure, spectral shift, and presence of cirrus above the liquid water clouds were quantified. Cirrus clouds and spectral shifts are the major sources of errors in the retrieval. An accurate spectral characterization of the OCO bands and an effective mask for pixels contaminated by cirrus would mostly eliminate these errors.

scholarly journals Influence of fluorescent pigments on the spectral characteristics of luminous coated fabrics

2021 ◽  
Author(s):  
Jing Li ◽  
Yanan Zhu ◽  
Mingqiao Ge
Keyword(s):  
Emission Spectrum ◽  
Spectral Characteristics ◽  
Woven Fabric ◽  
Luminescent Materials ◽  
Light Emitting ◽  
Fluorescent Pigment ◽  
Coated Fabric ◽  
Coated Fabrics ◽  
Green Fluorescent ◽  
Color Rendering

Abstract In recent years, luminous coated fabrics based on SrAl2O4: Eu2+, Dy3+ luminescent materials have attracted more attention. However, due to the single emission color of SrAl2O4: Eu2+, Dy3+ luminescent materials, the application of prepared coated fabrics has certain liminations. Therefore, at present, there is a need to develop a kind of luminous coated fabric which has the capability of emitting multiple colors of light. In this work, fluorescent pigments and SrAl2O4: Eu2+, Dy3+ luminescent materials were added to a coating slurry and uniformly coated over a woven fabric substrate. The effects of adding fluorescent pigments on the spectral characteristics of luminous coated fabrics were evaluated. The blue fluorescent pigment causes a significant blue shift in the emission spectrum of the blue light-emitting coated fabric, whereas the emission spectra of the orange and red light-emitting coated fabrics exhibit a significant red shift. The yellow-green fluorescent pigments significantly affect the coated fabric. The emission spectrum shows no evident change and is similar to the emission spectrum of white (without any fluorescent pigment) luminescent coated fabric. The afterglow brightness of the colored luminous coated fabrics decreases exponentially with time. Adding blue fluorescent pigments has a greater impact on the brightness of the coated fabrics. The initial brightness is lower and the afterglow brightness loss is higher when using yellow-green fluorescence. The pigment has little effect on the brightness loss of coated fabrics, and the initial brightness of the coated fabric increases when adding yellow-green fluorescent pigments. Fluorescent pigments result in relatively low color purity for each colored coated fabric. However, the color rendering index is high, and the color rendering performance for the light source is excellent.

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