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2013

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Articles 1501 - 1530 of 11462

Full-Text Articles in Physical Sciences and Mathematics

Pre-Breakdown Arcing In Dielectrics Under Electric Field Stress, Allen Andersen, Jr Dennison Oct 2013

Pre-Breakdown Arcing In Dielectrics Under Electric Field Stress, Allen Andersen, Jr Dennison

Graduate Student Presentations

No abstract provided.

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Catalytic Methyl Transfer From Dimethylcarbonate To Carboxylic Acids, Yuan Ji, Jessica Sweeney, Jillian Zoglio, David J. Gorin Oct 2013

Catalytic Methyl Transfer From Dimethylcarbonate To Carboxylic Acids, Yuan Ji, Jessica Sweeney, Jillian Zoglio, David J. Gorin

Chemistry: Faculty Publications

Although methylation reactions are commonplace, currently used reagents are hazardous, toxic, and/or unstable. Dimethylcarbonate has been put forth as an inexpensive, nontoxic, and “green” potential methylating reagent. Herein we report a general, base-catalyzed methyl transfer from dimethylcarbonate to carboxylic acids. High selectivity for esterification is observed even in the presence of unprotected phenols, and the mild reaction conditions enable conservation of stereochemistry at epimerizable stereocenters. Isotope-labeling studies suggest a mechanism proceeding by direct methyl transfer from dimethylcarbonate to the substrate.

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2012 Chesapeake Bay Sav Coverage, Sav Data Administrator, Virginia Institute Of Marine Science Oct 2013

2012 Chesapeake Bay Sav Coverage, Sav Data Administrator, Virginia Institute Of Marine Science

Data

Abstract: The 2012 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, particularly along narrow tributaries may not have been …

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Electrochemical Reduction Of Aqueous Uranium, Jonathan M. Scaggs Oct 2013

Electrochemical Reduction Of Aqueous Uranium, Jonathan M. Scaggs

Boise State University Theses and Dissertations

The electrochemical reduction of uranium in acidic aqueous environments with the express purpose of generating U(III) consistently is critically evaluated. Generating U(III) in an aqueous environment is difficult and extremely unstable and has historically been difficult to achieve and isolate for further investigation. The electrochemical cell, electrodes, supporting electrolytes, and pH’s are all reviewed and evaluated for the purpose of optimizing the systemic requirements to electrochemically generate U(III). Several new types of electrochemical cells to include two new spectroelectrochemical for UV-Vis and FT-Raman investigation were designed and tested for the purpose of analyzed the redox species of aqueous uranium generated …

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Satellite And Ground-Based Measurements Of Mesospheric Temperature Variability Over Cerro Pachon, Chile (30.3° S), Jonathan R. Pugmire, Michael J. Taylor, Yucheng Zhao, P Dominique Pautet, James M. Russell Iii Oct 2013

Satellite And Ground-Based Measurements Of Mesospheric Temperature Variability Over Cerro Pachon, Chile (30.3° S), Jonathan R. Pugmire, Michael J. Taylor, Yucheng Zhao, P Dominique Pautet, James M. Russell Iii

Jonathan Pugmire

Observations of mesospheric OH (6,2) rotational temperatures by the Utah State University Mesospheric Temperature Mapper (MTM) located at the Andes Lidar Observatory, Cerro Pachon, Chile (30.3° S, 70.7° W) reveal a large range of nightly variations induced by atmospheric gravity waves and tides, as well as strong seasonal oscillations. This study investigates MTM temperature variability over the past 4 years comprising over 800 nights of high-quality data and compares the results with MTM measurements from Maui, Hawaii (2001-2005) and coincident mesospheric temperature measurement by the SABER instrument on the NASA TIMED satellite.

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Air Blasting As The Optimal Approach For The Extraction Of Antioxidants In Coral Tissue, Elisabeth Deschaseaux, Myrna Deseo, Kellie Shepherd, Graham Jones, Peter Harrison Oct 2013

Air Blasting As The Optimal Approach For The Extraction Of Antioxidants In Coral Tissue, Elisabeth Deschaseaux, Myrna Deseo, Kellie Shepherd, Graham Jones, Peter Harrison

Dr Myrna A Deseo

In order to accurately measure the antioxidant capacity in corals, it is essential to optimally extract antioxidants from coral tissue. Here, we compared the two most commonly used methods for coral tissue extraction, air blasting (similar to Water-Pik method) and grinding, with or without sonication, to optimally extract antioxidants in corals. By air blasting, the coral tissue was stripped off the skeleton with a stream of compressed air into a polyethylene bag containing a known volume of buffer, whereas by grinding, both the coral tissue and skeleton were crushed using a mortar and pestle into a powder and homogenised in …

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The Fierce Green Fire: Vol. 4 Issue 7, Wofford College Environmental Studies Program Oct 2013

The Fierce Green Fire: Vol. 4 Issue 7, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

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The Santa Clara, 2013-10-17, Santa Clara University Oct 2013

The Santa Clara, 2013-10-17, Santa Clara University

The Santa Clara

No abstract provided.

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Application Of The Local Fractional Series Expansion Method And The Variational Iteration Method To The Helmholtz Equation Involving Local Fractional Derivative Operators, Yang Xiaojun Oct 2013

Application Of The Local Fractional Series Expansion Method And The Variational Iteration Method To The Helmholtz Equation Involving Local Fractional Derivative Operators, Yang Xiaojun

Xiao-Jun Yang

We investigate solutions of the Helmholtz equation involving local fractional derivative operators. We make use of the series expansion method and the variational iteration method, which are based upon the local fractional derivative operators. The nondifferentiable solution of the problem is obtained by using these methods.

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Hst Hot-Jupiter Transmission Spectral Survey: Evidence For Aerosols And Lack Of Tio In The Atmosphere Of Wasp-12b, David K. Sing, Alain Lecavelier Des Etangs, Jonathan J. Fortney, Adam Burrows, Frederic Pont, Hannah R. Wakeford, Gilda E. Ballester, Nikolay Nikolov, Gregory W. Henry, Suzanne Aigrain, Drake Deming, Thomas M. Evans, Neale P. Gibson, Catherine M. Huitson, Heather Knutson, Adam P. Showman, Alfred Vidal-Madjar, Paul A. Wilson, Michael H. Williamson, Kevin J. Zahnle Oct 2013

Hst Hot-Jupiter Transmission Spectral Survey: Evidence For Aerosols And Lack Of Tio In The Atmosphere Of Wasp-12b, David K. Sing, Alain Lecavelier Des Etangs, Jonathan J. Fortney, Adam Burrows, Frederic Pont, Hannah R. Wakeford, Gilda E. Ballester, Nikolay Nikolov, Gregory W. Henry, Suzanne Aigrain, Drake Deming, Thomas M. Evans, Neale P. Gibson, Catherine M. Huitson, Heather Knutson, Adam P. Showman, Alfred Vidal-Madjar, Paul A. Wilson, Michael H. Williamson, Kevin J. Zahnle

Information Systems and Engineering Management Research Publications

We present Hubble Space Telescope (HST) optical transmission spectra of the transiting hot-Jupiter WASP-12b, taken with the Space Telescope Imaging Spectrograph instrument. The resulting spectra cover the range 2900–10 300 Å which we combined with archival Wide Field Camera 3 spectra and Spitzer photometry to cover the full optical to infrared wavelength regions. With high spatial resolution, we are able to resolve WASP-12A's stellar companion in both our images and spectra, revealing that the companion is in fact a close binary M0V pair, with the three stars forming a triple-star configuration. We derive refined physical parameters of the WASP-12 system, …

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Photothermal Deflection Spectroscopy Of Amorphous, Nanostructured And Nanocomposite Thin Films, Muhammad Shafiq Ahmed Oct 2013

Photothermal Deflection Spectroscopy Of Amorphous, Nanostructured And Nanocomposite Thin Films, Muhammad Shafiq Ahmed

Electronic Thesis and Dissertation Repository

The energy needs of the modern world are growing day by day, while sources of non-renewable fossil fuels are limited, so there is a need to efficiently use the existing resources and explore renewable energy sources. In order to harvest, store and efficiently utilize renewable energy, we need to explore new materials and improve the performance of existing ones. Among others, hydrogenated amorphous silicon (a-Si:H) with high optical absorption in the visible range of electromagnetic spectrum, is a low cost material for solar cells. But the efficiency of such solar cells is comparatively low because of intrinsic defects associated with …

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Ionospheric Signatures Of Acoustic Waves Generated By Transient Tropospheric Forcing, M. D. Zettergren, J. B. Snively Oct 2013

Ionospheric Signatures Of Acoustic Waves Generated By Transient Tropospheric Forcing, M. D. Zettergren, J. B. Snively

Publications

Acoustic waves generated by tropospheric sources may attain significant amplitudes in the thermosphere and overlying ionosphere. Although they are weak precursors to gravity waves in the mesosphere below, acoustic waves may achieve temperature and vertical wind perturbations on the order of approximately tens of Kelvin and m/s throughout the E and F regions. Their perturbations to total electron content are predicted to be detectable by groundbased radar and GPS receivers; they also drive field-aligned currents that may be detectable in situ via magnetometers. Although transient and short lived, ionospheric signatures of acoustic waves may provide new and quantitative insight into …

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Doping The Nematic Liquid Crystal 5cb With Milled Batio3 Nanoparticles, Alexander Lorenz, Natalie Zimmerman, Satyendra Kumar, Dean R. Evans, Gary Cook, Hienz-S. Kitzerow Oct 2013

Doping The Nematic Liquid Crystal 5cb With Milled Batio3 Nanoparticles, Alexander Lorenz, Natalie Zimmerman, Satyendra Kumar, Dean R. Evans, Gary Cook, Hienz-S. Kitzerow

Satyendra Kumar

The simple nematic mesogen 5CB was doped with milled BaTiO3 nanoparticles and was investigated with x-ray scattering. Doping with BaTiO3 nanoparticles of 9 nm in diameter led to the formation of crystallites. These crystallites precipitated and formed a waxlike nanodispersion of 5CB and nanoparticles, which led to intense x-ray scattering signals characteristic of a multilayer structure. Surprisingly, the multilayers possess unusual interlayer spacing, which cannot be explained by simple smectic order of the calamitic molecules.

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Nematic Biaxiality In A Bent-Core Material, Hyungguen Yoon, Shin-Woong Kang, Ronald Y. Dong, Alberto Marini, Kattera A. Suresh, Mohan Srinivasarao, Satyendra Kumar Oct 2013

Nematic Biaxiality In A Bent-Core Material, Hyungguen Yoon, Shin-Woong Kang, Ronald Y. Dong, Alberto Marini, Kattera A. Suresh, Mohan Srinivasarao, Satyendra Kumar

Satyendra Kumar

The results of a recent investigation of the nematic biaxiality in a bent-core mesogen (A131) are in apparent disagreement with earlier claims. Samples of mesogen A131 used in the two studies were investigated with polarized optical microscopy, conoscopy, carbon-13 NMR, and crossover frequency measurements. The results demonstrate that textural changes associated with the growth of biaxial nematic order appear at similar to 149 degrees C. The Maltese cross observed in the conoscopic figure gradually splits into two isogyres at lower temperatures indicating phase biaxiality. Presence of the uniaxial to biaxial nematic phase transition is further confirmed by temperature trends of …

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Formation And Localization Of Internal Polymer Columnar Structures In Liquid Crystal Cells, Qingbing Wang, Liang-Chy Chien, Satyendra Kumar Oct 2013

Formation And Localization Of Internal Polymer Columnar Structures In Liquid Crystal Cells, Qingbing Wang, Liang-Chy Chien, Satyendra Kumar

Satyendra Kumar

Internal polymer columnar structures in liquid crystal (LC) cells have been produced using the method of thermally-induced phase separation of LC/prepolymer solution and solidified by photopolymerization. These polymer columns adhere to both substrates and enhance control of the LC cell spacing and mechanical stability. The existence and profile of the polymer columns were investigated by optical and scanning electron microscopy techniques. Supertwisted nematic LC cells with polymer columnar structures have been constructed using this method and their electro-optical characteristics measured.

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Material-Independent Determination Of Anchoring Properties On Rubbed Polyimide Surfaces, Bharat R. Acharya, Jae-Hoon Kim, Satyendra Kumar Oct 2013

Material-Independent Determination Of Anchoring Properties On Rubbed Polyimide Surfaces, Bharat R. Acharya, Jae-Hoon Kim, Satyendra Kumar

Satyendra Kumar

A material-independent method for determining liquid-crystal (LC) anchoring energy on rubbed polyimide (PI) surfaces has been devised. This method exploits the changes in the easy axis of rubbed PI film induced by exposure to linearly polarized UV (LPUV) Light. The distribution of PI chains in a rubbed film is approximated by a Gaussian function and its width determined from the measured rotation of the LC easy axis as a function of exposure time. A quasimicroscopic free energy of the LC-substrate interface is used to model LC anchoring properties. The experimental and calculated values of the azimuthal anchoring energy are in …

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Control Of Nematic Director Orientation By Exposing Rubbed Polyimide Films To Linearly Polarized Ultraviolet Light, Jae-Hoon Kim, Yushan Shi, Satyendra Kumar, Sin-Doo Lee Oct 2013

Control Of Nematic Director Orientation By Exposing Rubbed Polyimide Films To Linearly Polarized Ultraviolet Light, Jae-Hoon Kim, Yushan Shi, Satyendra Kumar, Sin-Doo Lee

Satyendra Kumar

The delicate interplay between the effects of mechanical rubbing and subsequent photo-induced chemical reactions on polyimide films has been studied for aligning liquid crystals. Exposure to linearly polarized ultraviolet (LPUV) light was found to profoundly alter the direction and the degree of molecular orientations obtained by rubbing. A simple model is presented to describe the observed changes in the director orientation. The results show that LPUV exposure can be very effectively used to control and fine-tune liquid crystal alignment.

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Effect Of Mosaicity In X-Ray Studies Of Critical Behavior At The Nematic To Smectic-A Transition, Andrew Primak, Michael Fisch, Satyendra Kumar Oct 2013

Effect Of Mosaicity In X-Ray Studies Of Critical Behavior At The Nematic To Smectic-A Transition, Andrew Primak, Michael Fisch, Satyendra Kumar

Satyendra Kumar

Previous studies of critical behavior at the nematic to smectic-A transition by high-resolution x-ray scattering were performed using low magnetic fields of 0.1-0.8 T. In those studies, the transverse resolution was limited by the sample mosaicity which complicated data analysis. In order to understand the effect of sample mosaicity on the measured values of critical exponents, the divergence of the smectic order correlation lengths xi(parallel to,perpendicular to) and susceptibility sigma(o) was studied in a magnetic field ranging from 0.25 to 5 T. The use of high (5 T) field reduced the sample mosaicity and improved the effective transverse resolution by …

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Absence Of The Incommensurate Smectic-A Phase In Db7ocn+8ocb Mixtures, Satyendra Kumar, Li Chien, V. Surendranath Oct 2013

Absence Of The Incommensurate Smectic-A Phase In Db7ocn+8ocb Mixtures, Satyendra Kumar, Li Chien, V. Surendranath

Satyendra Kumar

The results of a high-resolution x-ray-diffraction study of the smectic phases in mixtures of DB7OCN and 8OCB show that the incommensurate smectic-Ai2 phase, previously reported in this mixture, is in fact a coexistence of the partially bilayer smectic-Ad and the bilayer smectic-A2phases at a first-order phase transition between them.

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Onset And Evolution Of The Tilted Smectic Antiphase In A Polar Liquid-Crystal Binary Mixture, Yushan Shi, George Nounesis, Satyendra Kumar Oct 2013

Onset And Evolution Of The Tilted Smectic Antiphase In A Polar Liquid-Crystal Binary Mixture, Yushan Shi, George Nounesis, Satyendra Kumar

Satyendra Kumar

High-resolution x-ray diffraction studies of a binary mixture of the n = 8 and n = 10 homologs of alkoxyphenyl nitrobenzoyloxy benzoate DBnONO2 (52.6 mole % DB10ONO2) have been performed at the onset of the tilted smectic antiphase (Sm-C) upon cooling from the smectic-A(1) phase. Fluctuations of the two competing smectic orders are found to be related to monolayer and partial bilayer ordering. With decreasing temperature, the period of the antiphase in-plane modulation increases while the smectic layer normal tilts at an angle of +/-7 degrees with respect to the director. This tilt partially recovers upon the transition to the …

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Critical Behavior At The Nematic To Lamellar Phase Transitions: A Synchrotron X-Ray Scattering Study, S. T. Shin, J. D. Brock, Mark Sutton, J. D. Lister, Satyendra Kumar Oct 2013

Critical Behavior At The Nematic To Lamellar Phase Transitions: A Synchrotron X-Ray Scattering Study, S. T. Shin, J. D. Brock, Mark Sutton, J. D. Lister, Satyendra Kumar

Satyendra Kumar

The nematic (N) to lamellar (Lα) phase transition in binary mixtures of cesium-perfluoro-octanoate (CsPFO) and water has been studied by high-resolution synchrotron x-ray scattering at 46.6 weight % CsPFO. The longitudinal correlation length ξ∥ and the susceptibility σ associated with the lamellar phase fluctuations in the N phase, measured over three decades of reduced temperature, diverge with critical exponents ν∥=0.86±0.04 and γ=1.37±0.11, respectively. These results show that the N to Lα phase transition is quantitatively similar to the N to smectic-A phase transition of thermotropic liquid crystals with a wider nematic range.

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High Resolution X-Ray Diffraction Study Of Smectic Polymorphism And Fluctuations In A Mixture Of Octyl- And Decyl-Oxyphenyl Nitrobenzoyloxy Benzoate, Yushan Shi, George Nounesis, Carl W. Garland, Satyendra Kumar Oct 2013

High Resolution X-Ray Diffraction Study Of Smectic Polymorphism And Fluctuations In A Mixture Of Octyl- And Decyl-Oxyphenyl Nitrobenzoyloxy Benzoate, Yushan Shi, George Nounesis, Carl W. Garland, Satyendra Kumar

Satyendra Kumar

Reentrant nematic phases and smectic antiphases occur as intermediate states between two one-dimensionally ordered frustrated smectic phases, characterized by two competing and, in general, incommensurate smectic density waves. Using high-resolution x-ray diffraction, we have examined the evolution of the two density waves as a function of temperature in all phases of a mixture of polar liquid crystals octyl-and decyl-oxyphenyl nitrobenzoyloxy benzoate (47.4 mol% DB8ONO2+52.6% DB10ONO2). This mixture exhibits at temperatures below 127 degrees C the liquid-crystal phase sequence: smectic-A(d), reentrant nematic phases N-d and N-1, smectic-A(1), tilted antiphase (C) over tilde, smectic-A(2), and smectic-C-2 phases. Detailed investigations of several order-disorder …

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Dynamics Of Molecular Exchange Between Aligning Adsorbed Film Of Liquid Crystal And The Bulk, Rui Guo, Yuriy Reznikov, Kostyantyn Slyusarenko, Satyendra Kumar Oct 2013

Dynamics Of Molecular Exchange Between Aligning Adsorbed Film Of Liquid Crystal And The Bulk, Rui Guo, Yuriy Reznikov, Kostyantyn Slyusarenko, Satyendra Kumar

Satyendra Kumar

The liquid crystal (LC) originally filled in thin cells is replaced by a different LC having a drastically different pretilt angle. The mechanism of desorption/adsorption of LC molecules from/on the adsorbed LC film at the substrate changes the composition of the adsorbed layer and thus the pretilt angle. The time dependence of molecular pretilt angle at solid surfaces of homogeneously aligned LC cells is measured. The characteristic molecular exchange time depends on the coefficients of desorption of the first LC. The results presented here provide an important insight into the molecular exchange between solid surface and bulk fluid. (C) 2008 …

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Analytical Solution Of Maxwell's Equations In Lossy And Optically Active Crystals, Haijun Yuan, E. Weinan, Peter Palffy-Muhoray Oct 2013

Analytical Solution Of Maxwell's Equations In Lossy And Optically Active Crystals, Haijun Yuan, E. Weinan, Peter Palffy-Muhoray

Peter Palffy-Muhoray

Analytical solution of Maxwell's equations is obtained for general linear optical materials: lossy and optically active crystals. Explicit expressions are obtained for the dispersion relation and the propagating eigenmodes. In general, four rather than two distinct modes are present. The results are useful in describing light propagation in optically complex media.

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Surface-Induced Discrete Smectic Order In The Isotropic-Phase Of 12cb In Cylindrical Pores, Germano S. Iannacchione, Joseph T. Mang, Satyendra Kumar, Daniele Finotello Oct 2013

Surface-Induced Discrete Smectic Order In The Isotropic-Phase Of 12cb In Cylindrical Pores, Germano S. Iannacchione, Joseph T. Mang, Satyendra Kumar, Daniele Finotello

Satyendra Kumar

No abstract provided.

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Biaxial Nematic Phase In Bent-Core Thermotropic Mesogens, Bharat R. Acharya, Andrew Primak, Satyendra Kumar Oct 2013

Biaxial Nematic Phase In Bent-Core Thermotropic Mesogens, Bharat R. Acharya, Andrew Primak, Satyendra Kumar

Satyendra Kumar

A biaxial nematic phase had been predicted with D2h symmetry, wherein the mesogen’s long and short transverse axes are simultaneously aligned along the two orthogonal, primary and secondary directors, n and m, respectively. The unique low-angle x-ray diffraction patterns in the nematic phases exhibited by three rigid bent-core mesogens clearly reveal their biaxiality. The results of x-ray diffraction can be readily reproduced by ab initio calculations that explicitly include the bent-core shape in the form factor and assume short-range positional correlations.

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Cholesteric Gratings With Field-Controlled Period, Darius Subacius, Sergij V. Shiyanovskii, Philip J. Bos, Oleg Lavrentovich Oct 2013

Cholesteric Gratings With Field-Controlled Period, Darius Subacius, Sergij V. Shiyanovskii, Philip J. Bos, Oleg Lavrentovich

Oleg Lavrentovich

Diffractive gratings with period varied by an electric field are developed using a cholesteric liquid crystal confined between two transparent electrodes with unidirectionally treated alignment layers. In the initial state (zero field), the cholesteric layers are parallel to the cell planes. The electric field creates an in-plane modulated structure of variable period. Diffraction regimes of both Raman-Nath and Bragg types are demonstrated. (C) 1997 American Institute of Physics.

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Approximate Description Of The Three Dimensional Director And Electric Field In A Liquid Crystal Display At A High Voltage, G. Panasyuk, David W. Allender Oct 2013

Approximate Description Of The Three Dimensional Director And Electric Field In A Liquid Crystal Display At A High Voltage, G. Panasyuk, David W. Allender

David W Allender

An approximate analytical approach for describing properties of a liquid crystal display associated with a homeotropic to multidomainlike transition for a liquid crystal with a positive dielectricanisotropy was developed. The electrode and surface coating of the display are prepared in such a way that in the absence of an electric field (dark state) the liquid crystal alignment is homeotropic. The bright state corresponds to a situation when a high voltage is applied to the interdigitated electrodes located on both substrates, which causes a director deformation of a multidomain type. Approximate solutions for the three dimensional electric field and director configuration …

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Efficient, Polarization-Independent, Reflective Liquid Crystal Phase Grating, C. M. Titus, Philip J. Bos Oct 2013

Efficient, Polarization-Independent, Reflective Liquid Crystal Phase Grating, C. M. Titus, Philip J. Bos

Philip J. Bos

A reflective liquid crystal diffraction grating is proposed which makes use of the maximum available surface area. The structure consists of alternating stripes, each a twisted-nematic domain with surface orientation perpendicular to that of its neighbors. All domains have the same twist sense. This device yields, in principle, 100% diffraction efficiency independent of incident polarization. (C) 1997 American Institute of Physics.

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Broadband Optical Phased-Array Beam Steering, Paul F. Mcmanamon, Jianru Shi, Philip J. Bos Oct 2013

Broadband Optical Phased-Array Beam Steering, Paul F. Mcmanamon, Jianru Shi, Philip J. Bos

Philip J. Bos

An array of phase retarders can be used as an optical phased array (OPA) to steer light [McManamon et al., Proc. IEEE 84 (2), 268 298 (1996)]. The introduction of resets enables steering to larger angles without requiring an optical path difference (OPD) greater than one wavelength. These resets, however, are correct only at the design wavelength. The beam steerer is therefore very dispersive. It has been shown theoretically that resets of an integer multiple of the wavelength will make the beam steerer less dispersive [McManamon and Watson, Proc. SPIE 4369, 140-148 (2001)]. We offer the first experimental proof that …

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