Energy loss due to plasmon excitation by the impact of charged particles on solid surfaces: Beyond a standard approximation

Small particles exhibit chemical and physical behaviors substantially different from bulk materials. This is due to the fact that boundary conditions can induce specific constraints on the observed properties. As an example, energy loss experiments carried out in an analytical electron microscope, constitute a powerful technique to investigate the excitation of collective surface modes (plasmons), which are modified in a limited size medium. In this work a STEM VG HB501 has been used to study the low energy loss spectrum (1-40 eV) of silicon spherical particles [1], and the spatial localization of the different modes has been analyzed through digitally acquired energy filtered images. This material and its oxides have been extensively studied and are very well characterized, because of their applications in microelectronics. These particles are thus ideal objects to test the validity of theories developed up to now.Typical EELS spectra in the low loss region are shown in fig. 2 and energy filtered images for the main spectral features in fig. 3.

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Atomic resolution characterisation of interface structures by Electron Energy Loss Spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014871x ◽

1993 ◽

Vol 51 ◽

pp. 576-577

Author(s):

N. D. Browning ◽

M. M. McGibbon ◽

M. F. Chisholm ◽

S. J. Pennycook

Keyword(s):

High Resolution ◽

Energy Loss ◽

Electron Energy ◽

Electron Energy Loss Spectroscopy ◽

Imaging Technique ◽

Atomic Scale ◽

Atomic Resolution ◽

Reference Image ◽

The Impact ◽

Electron Energy Loss

The recent development of the Z-contrast imaging technique for the VG HB501 UX dedicated STEM, has added a high-resolution imaging facility to a microscope used mainly for microanalysis. This imaging technique not only provides a high-resolution reference image, but as it can be performed simultaneously with electron energy loss spectroscopy (EELS), can be used to position the electron probe at the atomic scale. The spatial resolution of both the image and the energy loss spectrum can be identical, and in principle limited only by the 2.2 Å probe size of the microscope. There now exists, therefore, the possibility to perform chemical analysis of materials on the scale of single atomic columns or planes.In order to achieve atomic resolution energy loss spectroscopy, the range over which a fast electron can cause a particular excitation event, must be less than the interatomic spacing. This range is described classically by the impact parameter, b, which ranges from ~10 Å for the low loss region of the spectrum to <1Å for the core losses.

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Multiple interactions in riverine biofilms - surfactant adsorption, bacterial attachment and biodegradation

Water Science & Technology ◽

10.2166/wst.1995.0015 ◽

1995 ◽

Vol 31 (1) ◽

pp. 61-70 ◽

Cited By ~ 6

Author(s):

Graham F. White

Keyword(s):

Organic Pollutants ◽

Bacterial Attachment ◽

Solid Surfaces ◽

Sediment Surface ◽

Liquid Interfaces ◽

Polluted Soils ◽

Biofilm Bacteria ◽

The Impact ◽

Multiple Interactions

Many organic pollutants, especially synthetic surfactants, adsorb onto solid surfaces in natural and engineered aquatic environments. Biofilm bacteria on such surfaces make major contributions to microbial heterotrophic activity and biodegradation of organic pollutants. This paper reviews evidence for multiple interactions between surfactants, biodegradative bacteria, and sediment-liquid interfaces. Biodegradable surfactants e.g. SDS, added to a river-water microcosm were rapidly adsorb to sediment surface and stimulated the indigenous bacteria to attach to the sediment particles. Recalcitrant surfactants and non-surfactant organic nutrients did not stimulate attachment Attachment of bacteria was maximal when biodegradation was fastest, and was reversed when biodegradation was complete. Dodecanol, the primary product of SDS-biodegradation, markedly stimulated attachment. When SDS was added to suspensions containing sediment and either known degraders or known non-degraders, only the degraders became attached, and attachment accelerated surfactant biodegradation to dodecanol. These cyclical cooperative interactions have implications for the design of biodegradability-tests, the impact of surfactant adjuvants on biodegradability of herbicides/pesticides formulated with surfactants, and the role of surfactants used to accelerate bioremediation of hydrocarbon-polluted soils.

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Role of the kinematics of probing electrons in electron energy-loss spectroscopy of solid surfaces

Physical Review B ◽

10.1103/physrevb.93.035403 ◽

2016 ◽

Vol 93 (3) ◽

Cited By ~ 4

Author(s):

V. U. Nazarov ◽

V. M. Silkin ◽

E. E. Krasovskii

Keyword(s):

Energy Loss ◽

Electron Energy ◽

Electron Energy Loss Spectroscopy ◽

Solid Surfaces ◽

Electron Energy Loss

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Energy Loss Due to Adhesion During the Impact of Elastic Spheres

Procedia Engineering ◽

10.1016/j.proeng.2016.12.004 ◽

2017 ◽

Vol 173 ◽

pp. 238-243 ◽

Cited By ~ 2

Author(s):

U.B. Jayadeep ◽

M.S. Bobji

Keyword(s):

Energy Loss ◽

The Impact

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The interaction of atomic particles with solid surfaces at intermediate energies IV. The energy and angular distributions of particles scattered with electric charge from polycrystalline platinum at bombarding energies of 500-5000 eV

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1974.0183 ◽

1974 ◽

Vol 341 (1625) ◽

pp. 213-231 ◽

Cited By ~ 4

Keyword(s):

Charged Particles ◽

Solid Surfaces ◽

Hydrogen Ion ◽

Angular Distributions ◽

Sodium Potassium ◽

Intermediate Energies ◽

Polycrystalline Platinum ◽

Composite Spectra ◽

Energy And Angular Distributions ◽

Bombarding Energy

The distributions in angle and energy for charged particles emitted from polycrystalline platinum bombarded with ions of hydrogen, sodium, potassium and some hydrocarbons, have been measured, in continuation of previous work (Cawthron, Cotterell & Oliphant 1969 a , b , parts I and II; 1970, part III) to lower energies. Composite spectra are presented, including ions of both signs. The flux of emitted charged particles, under hydrogen ion bombardment, is shown to contain approximately equal numbers of protons and H¯ ions, except at the lowest bombarding energies, where the latter apparently predominate. Scattering in all cases is shown to increase with bombarding energy over the range covered, the increase being near linear for hydrogen and very rapid for alkalimetal ions. In all cases the total emission of charged particles is very small at the lowest bombarding energies employed.

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A mixed contact model for an immersed collision between two solid surfaces

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2008.0014 ◽

2008 ◽

Vol 366 (1873) ◽

pp. 2205-2218 ◽

Cited By ~ 19

Author(s):

Fu-Ling Yang ◽

Melany L Hunt

Keyword(s):

Surface Deformation ◽

Elastohydrodynamic Lubrication ◽

Solid Particles ◽

Solid Surfaces ◽

Additional Energy ◽

Collision Model ◽

Dry Granular Flow ◽

Wide Range ◽

The Impact ◽

Surrounding Liquid

Experimental evidence shows that the presence of an ambient liquid can greatly modify the collision process between two solid surfaces. Interactions between the solid surfaces and the surrounding liquid result in energy dissipation at the particle level, which leads to solid–liquid mixture rheology deviating from dry granular flow behaviour. The present work investigates how the surrounding liquid modifies the impact and rebound of solid spheres. Existing collision models use elastohydrodynamic lubrication (EHL) theory to address the surface deformation under the developing lubrication pressure, thereby coupling the motion of the liquid and solid. With EHL theory, idealized smooth particles are made to rebound from a lubrication film. Modified EHL models, however, allow particles to rebound from mutual contacts of surface asperities, assuming negligible liquid effects. In this work, a new contact mechanism, ‘mixed contact’, is formulated, which considers the interplay between the asperities and the interstitial liquid as part of a hybrid rebound scheme. A recovery factor is further proposed to characterize the additional energy loss due to asperity–liquid interactions. The resulting collision model is evaluated through comparisons with experimental data, exhibiting a better performance than the existing models. In addition to the three non-dimensional numbers that result from the EHL analysis—the wet coefficient of restitution, the particle Stokes number and the elasticity parameter—a fourth parameter is introduced to correlate particle impact momentum to the EHL deformation impulse. This generalized collision model covers a wide range of impact conditions and could be employed in numerical codes to simulate the bulk motion of solid particles with non-negligible liquid effects.

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