Light Scattering in Stretched Rubber

1940 ◽  
Vol 13 (2) ◽  
pp. 285-289 ◽  
Author(s):  
H. A. Schwarzenbach
Keyword(s):  
Light Scattering ◽  
Visible Light ◽  
Test Specimen ◽  
Scattered Light ◽  
Transmitted Light ◽  
Bright Spot ◽  
Special Device ◽  
Experimental Apparatus ◽  
First Results

Abstract It is already known that when pure rubber is stretched in one direction it acquires a lustre. This means that light falling upon it is scattered with appreciably different intensities at various angles to the direction in which the rubber is stretched. In view of this and in connection with earlier experiments, a study of the scattering of visible light by stretched rubber was undertaken and the first results are reported in a brief way in the present paper. First of all, however, it is well to describe the experimental apparatus and technique which were used. A practically parallel, sharp beam of light was produced, the direction of which may be represented by the X-axis of a system of right-angle coordinates. The rubber test-specimen, in the form of a strip, was placed in such a position in the path of this beam of light that it was illuminated by the beam at right angles to its surface. In other words, the specimen lay in the YZ plane of the coördinate system and by means of a special device it could be stretched in the Z direction. At a suitable distance behind the test-specimen a smooth, transparent paper screen was placed, likewise at right angles to the direction of the beam of light. The distribution of the scattered light around the bright spot formed by the transmitted light could be observed by eye and could be photographed by a camera. Samples of rubber as nearly pure as possible and containing no fillers were examined, including not only films prepared from pure unvulcanized and partially vulcanized latex, but also strips prepared from commercial sheets of “patent rubber” and from Para rubber.

A Time-Resolved Low-Angle Light Scattering Apparatus. Application to Phase Separation Problems in Polymer Systems

2001 ◽  
Vol 66 (6) ◽  
pp. 973-982 ◽  
Author(s):  
Čestmír Koňák ◽  
Jaroslav Holoubek ◽  
Petr Štěpánek
Keyword(s):  
Phase Separation ◽  
Light Scattering ◽  
Signal To Noise Ratio ◽  
Scattered Light ◽  
Ccd Camera ◽  
Time Resolved ◽  
Polymer Systems ◽  
Software Analysis ◽  
Phase Separation Kinetics ◽  
Small Angle Light Scattering

A time-resolved small-angle light scattering apparatus equipped with azimuthal integration by means of a conical lens or software analysis of scattering patterns detected with a CCD camera was developed. Averaging allows a significant reduction of the signal-to-noise ratio of scattered light and makes this technique suitable for investigation of phase separation kinetics. Examples of applications to time evolution of phase separation in concentrated statistical copolymer solutions and dissolution of phase-separated domains in polymer blends are given.

scholarly journals Light-Scattering Simulations from Spherical Bimetallic Core–Shell Nanoparticles

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 359
Author(s):  
Francesco Ruffino
Keyword(s):  
Optical Properties ◽  
Light Scattering ◽  
Bimetallic Nanoparticles ◽  
Dominant Role ◽  
Scattered Light ◽  
Specific Interaction ◽  
Surface Enhanced Raman Spectroscopy ◽  
Localized Surface Plasmon ◽  
Core Shell ◽  
The Core

Bimetallic nanoparticles show novel electronic, optical, catalytic or photocatalytic properties different from those of monometallic nanoparticles and arising from the combination of the properties related to the presence of two individual metals but also from the synergy between the two metals. In this regard, bimetallic nanoparticles find applications in several technological areas ranging from energy production and storage to sensing. Often, these applications are based on optical properties of the bimetallic nanoparticles, for example, in plasmonic solar cells or in surface-enhanced Raman spectroscopy-based sensors. Hence, in these applications, the specific interaction between the bimetallic nanoparticles and the electromagnetic radiation plays the dominant role: properties as localized surface plasmon resonances and light-scattering efficiency are determined by the structure and shape of the bimetallic nanoparticles. In particular, for example, concerning core-shell bimetallic nanoparticles, the optical properties are strongly affected by the core/shell sizes ratio. On the basis of these considerations, in the present work, the Mie theory is used to analyze the light-scattering properties of bimetallic core–shell spherical nanoparticles (Au/Ag, AuPd, AuPt, CuAg, PdPt). By changing the core and shell sizes, calculations of the intensity of scattered light from these nanoparticles are reported in polar diagrams, and a comparison between the resulting scattering efficiencies is carried out so as to set a general framework useful to design light-scattering-based devices for desired applications.

Numerical Simulation and Experimental Study on Light Scattering by Biological Cells with Discrete Dipole Approximation

2013 ◽  
Vol 760-762 ◽  
pp. 105-109 ◽  
Author(s):  
Jian Bin Liu ◽  
Hai Li ◽  
Ying Xin Zeng ◽  
Jia Wen Weng ◽  
Chu Ping Yang
Keyword(s):  
Cell Culture ◽  
Light Scattering ◽  
Culture Medium ◽  
Dipole Approximation ◽  
Spherical Particles ◽  
Biological Cells ◽  
Cell Culture Medium ◽  
Animal Cells ◽  
Experimental Apparatus ◽  
Liquid Suspensions

An experimental apparatus for the analysis of biological cells light scattering in liquid suspensions has been presented. Characterization is based on the scattering of a monochromatic laser beam by particles [which can be inorganic, organic, or biological (such as animal cells and bacteria)] and on the strong relation between the light-scattering pattern and the morphology and refractive index of the particles. In order to study light scattering in biological cells close to the actual situation, we focus on non-spherical particles in the cell-culture medium. Finally, we demonstrate the light scattering results of bovine kidney cells suspended in the cell-culture medium, and compares then with the simulated results.

Tailoring Patterned Visible-Light Scattering by Silicon Photonic Crystals

2021 ◽  
Author(s):  
Pengfei Cheng ◽  
Ronald Kampmann ◽  
Dong Wang ◽  
Stefan Sinzinger ◽  
Peter Schaaf
Keyword(s):  
Light Scattering ◽  
Photonic Crystals ◽  
Visible Light ◽  
Silicon Photonic

scholarly journals Oil in Water Monitoring Using Advanced Light Scattering

2013 ◽  
Author(s):  
Gernot Seebacher ◽  
Axel A. Schmidt ◽  
Jochen Offermann
Keyword(s):  
Light Scattering ◽  
Oil Content ◽  
Scattered Light ◽  
Discharge Process ◽  
Water Mixture ◽  
Effluent Quality ◽  
Light Pattern ◽  
Bilge Water ◽  
Oil In Water ◽  
Wide Range

The paper provides background on how bilge water has changed over the years and how technology has enabled manufacturers to stay ahead of the curve by borrowing technological breakthroughs from other areas to the measurement of oil content in the marine environment. Light scattering provides today a universal and reliable method, able to measure the wide range of oils present in a wildly variable and unpredictable bilge water mixture. Bilge water regulations were put in place to reduce the potential of harm to the environment from oily bilge water discharges. Regulations require that instruments verify effluent quality continually during the discharge process, which precludes the adoption for shipboard use of standard laboratory style testing with the associated time delays to complete the analysis. Measuring oil content with the light scattering measuring instrument is a tried and tested means for compliant bilge water verification. State of the art instruments employ sophisticated light measuring systems and they use complex algorithms to convert the scattered light pattern values into oil content reading, thereby considering interference from other than oil suspended matter, they prevent harm to the environment from bilge water discharges. Paper published with permission.

scholarly journals First results from the Cluster wideband plasma wave investigation

2001 ◽  
Vol 19 (10/12) ◽  
pp. 1259-1272 ◽  
Author(s):  
D. A. Gurnett ◽  
R. L. Huff ◽  
J. S. Pickett ◽  
A. M. Persoon ◽  
R. L. Mutel ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Wave Packet ◽  
Plasma Wave ◽  
Bright Spot ◽  
Deep Space ◽  
Good Correspondence ◽  
Auroral Kilometric Radiation ◽  
First Results ◽  
One To One ◽  
The Magnetic Field

Abstract. In this report we present the first results from the Cluster wideband plasma wave investigation. The four Cluster spacecraft were successfully placed in closely spaced, high-inclination eccentric orbits around the Earth during two separate launches in July – August 2000. Each spacecraft includes a wideband plasma wave instrument designed to provide high-resolution electric and magnetic field wave-forms via both stored data and direct downlinks to the NASA Deep Space Network. Results are presented for three commonly occurring magnetospheric plasma wave phenomena: (1) whistlers, (2) chorus, and (3) auroral kilometric radiation. Lightning-generated whistlers are frequently observed when the spacecraft is inside the plasmasphere. Usually the same whistler can be detected by all spacecraft, indicating that the whistler wave packet extends over a spatial dimension at least as large as the separation distances transverse to the magnetic field, which during these observations were a few hundred km. This is what would be expected for nonducted whistler propagation. No case has been found in which a strong whistler was detected at one spacecraft, with no signal at the other spacecraft, which would indicate ducted propagation. Whistler-mode chorus emissions are also observed in the inner region of the magnetosphere. In contrast to lightning-generated whistlers, the individual chorus elements seldom show a one-to-one correspondence between the spacecraft, indicating that a typical chorus wave packet has dimensions transverse to the magnetic field of only a few hundred km or less. In one case where a good one-to-one correspondence existed, significant frequency variations were observed between the spacecraft, indicating that the frequency of the wave packet may be evolving as the wave propagates. Auroral kilometric radiation, which is an intense radio emission generated along the auroral field lines, is frequently observed over the polar regions. The frequency-time structure of this radiation usually shows a very good one-to-one correspondence between the various spacecraft. By using the microsecond timing available at the NASA Deep Space Net-work, very-long-baseline radio astronomy techniques have been used to determine the source of the auroral kilometric radiation. One event analyzed using this technique shows a very good correspondence between the inferred source location, which is assumed to be at the electron cyclotron frequency, and a bright spot in the aurora along the magnetic field line through the source.Key words. Ionosphere (wave-particle interactions; wave propagation) – Magnetospheric physics (plasma waves and instabilities; instruments and techniques)

Elastic Properties of Sputtered Thin Films: Influence of Different Preparation Conditions

1993 ◽  
Vol 308 ◽  
Author(s):  
C.E. Bottani ◽  
M. Elena ◽  
M. Beghi ◽  
G. Ghislotti ◽  
L. Guzman ◽  
...  
Keyword(s):  
Thin Films ◽  
Light Scattering ◽  
Hard Coatings ◽  
Elastic Behaviour ◽  
Internal Stresses ◽  
Pvd Coatings ◽  
Tin Films ◽  
Si Substrates ◽  
Preparation Conditions ◽  
First Results

ABSTRACTThis work presents the first results of a study aimed at better understanding the elastic behaviour of hard coatings produced by various techniques. This is important also in view of the need to be able to control the level of internal stresses, particularly in PVD coatings. It is well known that in extreme cases excessive internal stress can lead to complete film destruction. We devote this paper to reactively magnetron sputtered TiN, one of the most widely used compounds. Thin TiN films of different compositions were deposited on Si substrates and characterized by SEM, AES, XRD and Brillouin light scattering.

Platelet Aggregometry and Shape Change Measurement by Laser Light in Small Samples

1979 ◽  
Author(s):  
P. Blasberg ◽  
L.J. Wurzinper
Keyword(s):  
Hollow Fiber Membrane ◽  
Shape Change ◽  
Scattered Light ◽  
Transmitted Light ◽  
Small Samples ◽  
Change Measurement ◽  
Platelet Aggregometry ◽  
Space Angle ◽  
Flow Through ◽  
Set Up

A technique is presented to measure platelet aggregation (PA) and platelet shape change (PSC) with high accuracy in small samples (100 ul) using a turbidimetric method wich a He-Ne-Laser as light source. Both, transmitted and scattered light, Is measured by two independent light sensitive elements. Transmitted light is detected by a photodiode with a sensitive area of 1 mm2 covering a space angle of Ω= 0.004 sterad. Scattered light is detected by a photoelement surrounding the photodiode which covers a space angle of U-1.4 sterad. Ar, electronic set up forms a signal, which is proportional to the ratio scattered light/scattered light + transmitted light.The output voltage is linearly correlated to the turbidity of the suspension. The whole set up is employed with three different types of cuvettes.1. A cuvette where through a semipermeable hollow fiber membrane different drugs can diffuse into the platelet suspensions avoiding any stirring of the sample ()2. A flow through cuvette to measure the extent of PA in PRP samples.3. A couette type platelet aggregometer.

Sequential Extraction of Late Exponentials (SELE): A technique for deconvolving multimodal correlation curves in Dynamic Light Scattering

MRS Advances ◽  
2020 ◽  
Vol 5 (17) ◽  
pp. 865-880 ◽  
Author(s):  
Preethi L Chandran
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Sequential Extraction ◽  
Time Scales ◽  
Scattered Light ◽  
Correlation Spectroscopy ◽  
Least Square ◽  
Multiple Time Scales ◽  
Multiple Time ◽  
Correlation Curve

Abstract:In techniques such as Dynamic Light Scattering (DLS), Fluorescence Correlation Spectroscopy, and image mining, motion is tracked by the autocorrelation of a signal over logarithmic time scales. For instance the tracking signal in DLS is the scattered light intensity; it remains correlated at time scales where scant changes in the arrangement of the scattering particles occur, but decays exponentially at the time scales of their diffusion. When there are multiple time scales of motion (for instance due to scatterers of different sizes), the correlation curve has more than one exponential fall. Extracting the decay constants or hydrodynamic sizes due to each exponential fall in a multi-species field correlation curve becomes an ill-conditioned mathematical problem. We describe a new algorithm to invert a multi-modal correlation curve by Sequential Extraction of the Late Exponentials (SELE). The idea is that while the inversion of a multi-exponential equation may be ill posed, that of a single exponential is not. So we fit data windows towards to base of the correlation curve to extract the largest contribution species, remove the species contribution from the correlation curve, and repeat the process with the remnant curve. The single exponent can be robustly fitted by least-square minimization with initial guesses generated by an adapted cumutant technique (power-series) that includes stretch coefficients (measure of sample dispersity). The proposed algorithm resolves particle sizes separated by 3X, and is reliable against fluctuations in the correlation curve and to localized regions of suboptimal data. The algorithm can be used to track particle dynamics in solution in multi-species problems such as self-assembly.

Fractal and Polarization Properties of Light Scattering Using Microcrystalline Pharmaceutical Aggregates

2020 ◽  
Vol 75 (1) ◽  
pp. 94-106
Author(s):  
Jennifer Aldama ◽  
Zhenqi Shi ◽  
Carlos Ortega-Zúñiga ◽  
Rodolfo J. Romañach ◽  
Sergiy Lysenko
Keyword(s):  
Fractal Dimension ◽  
Light Scattering ◽  
Drug Concentration ◽  
Specular Reflection ◽  
Scattered Light ◽  
Strong Dependence ◽  
Single Scattering ◽  
Structural Morphology ◽  
Light Refraction ◽  
Measurement Protocol

Fractal and polarization analysis of diffusively scattered light is applied to determine the complex relationship between fractal dimension of structural morphology and concentration of chemically active ingredients in two pharmaceutical mixture systems including a series of binary mixtures of acetaminophen in lactose and three multicomponent blends with a proprietary active ingredient. A robust approach is proposed to identify and filter out multiple- and single-scattering components of scattering indicatrix. The fractal dimension extracted from scattering field reveals complex structural details of the sample, showing strong dependence on low-dose drug concentration in the blend. Low-angle diffraction shows optical “halo” patterns near the angle of specular reflection caused by light refraction in microcrystalline aggregates. Angular measurements of diffuse reflection demonstrate noticeable dependence of Brewster's angle on drug concentration. It is shown that the acetaminophen microcrystals produce scattered light depolarization due to their optical birefringence. The light scattering measurement protocol developed for diffusively scattered light by microcrystalline pharmaceutical compositions provides a novel approach for the pattern recognition, analysis and classification of materials with a low concentration of active chemical ingredients.

Sign in / Sign up

Export Citation Format

Share Document