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At least 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

First-principles calculations of the electronic structure and optical properties of K{sub 1-x}Na{sub x}TaO{sub 3} (x=0, 0.25, 0.5, 0.75, 1)

The first-principles calculations are performed to investigate the cubic phase composite K{sub 1-x}Na{sub x}TaO{sub 3}(x=0, 0.25, 0.5, 0.75, 1), by using density functional theory (DFT) with the full potential linearized augmented plane wave (FP-LAPW) method. The energy band structures, density of states (DOS), electron density and optical properties are obtained. The results show that Na ion plays an important role in K{sub 1-x}Na{sub x}TaO{sub 3}. With the content of Na ion increasing, the changes of lattice parameters, energy gaps, bond lengths and optical properties of K{sub 1-x}Na{sub x}TaO{sub 3} are regular. Moreover, the dependence of ferroelectric photocatalysis on both optical properties and internal electronic structure are analyzed in detail. It is proposed that the doped materials are promising photocatalytic materials. - Graphical abstract: The density of states (DOS) of K{sub 1-x}Na{sub x}TaO{sub 3} (x=0.5). Highlights: Black-Right-Pointing-Pointer The first-principles calculations are performed, by using DFT with FP-LAPW method. Black-Right-Pointing-Pointer The changes of internal electronic structure and optical property of doped materials are regular. Black-Right-Pointing-Pointer The dependence of ferroelectric photocatalysis on optical properties is analyzed. Black-Right-Pointing-Pointer The dependence of ferroelectric photocatalysis on internal electronic structure is analyzed. Black-Right-Pointing-Pointer The doped materials are promising photocatalytic materials.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Controlling ZIF-67 crystals formation through various cobalt sources in aqueous solution

Zeolitic imidazolate frameworks ZIF-67 were prepared under hydrothermal (120 °C) and non-hydrothermal (room temperature) from various cobalt sources and 2-methylimidazolate (Hmim) in aqueous solution within 30 min. The particle size and morphology were found to be related to the reactivity of the cobalt salt, Hmim/Co{sup 2+} molar ratios and experimental condition. Using Co(NO{sub 3}){sub 2} as cobalt source, small-sized ZIF-67 crystals with agglomeration were formed. For CoCl{sub 2}, small-sized rhombic dodecahedron were obtained. While large-sized crystals of rhombic dodecahedron structure were obtained from CoSO{sub 4} and Co(OAc){sub 2}. Under hydrothermal condition, the size of ZIF-67 crystals tended to be more uniform and the morphology were more regular comparing to non-hydrothermal condition. This study provides a simple way to control the size and morphology of ZIF-67 crystals prepared in aqueous solution. - Graphical abstract: Zeolitic imidazolate frameworks ZIF-67 were prepared under hydrothermal (120 °C) and non-hydrothermal (room temperature) from four different cobalt sources (Co(NO{sub 3}){sub 2}, CoCl{sub 2}, CoSO{sub 4} and Co(OAc){sub 2}) in aqueous solution within 30 min. The particle size and morphology were found to be related to the reactivity of the cobalt salt, Hmim/Co{sup 2+} molar ratios and experimental condition. - Highlights: • The particle size and morphology were determined by the reactivity of cobalt salt. • ZIF-67 could be prepared from CoSO{sub 4} and Co(OAc){sub 2} at Hmim/Co{sup 2+} molar ratio of 10. • Uniform and regular particles were obtained under hydrothermal condition.

36 MATERIALS SCIENCE↗
DOE OSTI2012

Study of preparation of TiB{sub 2} by TiC in Al melts

TiB{sub 2} particles are prepared by TiC in Al melts and the characteristics of them are studied. It is found that TiC particles are unstable when boron exists in Al melts with high temperature and will transform to TiB{sub 2} and Al{sub 4}C{sub 3}. Most of the synthesized TiB{sub 2} particles are regular hexagonal prisms with submicron size. The diameter of the undersurfaces of these prisms is ranging from 200 nm to 1 {mu}m and the height is ranging from 100 nm to 300 nm. It is considered that controlling the transformation from TiC to TiB{sub 2} is an effective method to prepare small and uniform TiB{sub 2} particles. - Highlights: Black-Right-Pointing-Pointer TiC can easily transform into TiB{sub 2} in Al melts. Black-Right-Pointing-Pointer TiB{sub 2} formed by TiC will grow into regular hexagonal prisms with submicron size. Black-Right-Pointing-Pointer Controlling the transformation from TiC to TiB{sub 2} is an effective method to prepare small and uniform TiB{sub 2} particles.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Evolution of microstructure, texture and inhibitor along the processing route for grain-oriented electrical steels using strip casting

In the present work, a regular grade GO sheet was produced successively by strip casting, hot rolling, normalizing annealing, two-stage cold rolling with intermediate annealing, primary recrystallization annealing, secondary recrystallization annealing and purification. The aim of this paper was to characterize the evolution of microstructure, texture and inhibitor along the new processing route by comprehensive utilization of optical microscopy, X-ray diffraction and transmission electron microscopy. It was found that a fine microstructure with the ferrite grain size range of 7–12 μm could be obtained in the primary recrystallization annealed sheet though a very coarse microstructure was produced in the initial as-cast strip. The main finding was that the “texture memory” effect on Goss texture started on the through-thickness intermediate annealed strip after first cold rolling, which was not similar to the “texture memory” effect on Goss texture starting on the surface layers of the hot rolled strip in the conventional production route. As a result, the origin of Goss nuclei capable of secondary recrystallization lied in the grains already presented in Goss orientation in the intermediate annealed strip after first cold rolling. Another finding was that fine and dispersive inhibitors (mainly AlN) were easy to be produced in the primary recrystallization microstructure due to the initial rapid solidification during strip casting and the subsequent rapid cooling, and the very high temperature reheating usually used before hot rolling in the conventional production route could be avoided. - Highlights: • A regular grade grain-oriented electrical steel was produced. • Evolution of microstructure, texture and inhibitor was characterized. • Origin of Goss nuclei lied in the intermediate annealed strip. • A fine primary recrystallization microstructure could be produced. • Effective inhibitors were easy to be obtained in the new processing route.

36 MATERIALS SCIENCE↗
DOE OSTI2015

In situ synchrotron X-ray studies of the coupled effects of thermal and solutal supercoolings on the instability of dendrite growth

Special growth pattern representing unique growth conditions is a vital clue to investigate the morphology evolution mechanism in metallic alloy solidification. The dendrite pattern and growth orientation of dendritic doublons in the hypoeutectic Al-Cu alloy have been studied by synchrotron radiation imaging technology and electron back scatter diffraction. The results show that this kind of doublon is two-dimensional and the secondary arms grow perpendicularly to the primary stem. This doublon morphology can appear as an equiaxed grain, columnar dendrite, or coexist with a regular dendrite. The growth directions of the dendritic doublon tips and the secondary arms are < 110 > and < 001 >, respectively. Rising cooling rate or Cu concentration in the alloys facilitates the formation of the doublonic structure. According to the kinetic morphology diagram of Al-Cu alloys (pattern-dimensionless supercooling-anisotropy) obtained from the experimental data, the dendritic doublon forming region was above the boundary of fractal dendrite and compact dendrite. - Highlights: • The morphology of dendritic doublon was found growing in equiaxed or columnar dendritic manner, or coexisting with regular stems in an equiaxed dendrite. • The growth orientations of dendritic doublon tip and secondary arms are < 110 > and < 001 >, respectively. • Doublon dendrite is considered a kind of transitional growth pattern; the variation of either Cu composition or cooling rate affects the formation probability of the doublon-type dendrite.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Observation of a new B2 structured phase in Ti-15Mo (wt%)

Highlights: • Ti-15Mo (wt%) studied in TEM during in situ heat treatment at 300 °C. • Initial microstructure (beta and athermal omega) evolved during exposure. • New B2 phase observed during heat treatment of electron transparent material. • B2 phase formed in regular arrays of square cross-section particles. • B2 phase lattice parameter smaller than beta phase resulting in misfit strain - Abstract: The formation of non-equilibrium and transient phases in metastable beta titanium alloys during low temperature thermal treatments is currently of great interest, as they provide a potential method of controlling the size and distribution of the equilibrium alpha phase and, hence, the resulting mechanical properties. Here, for the first time, we report on the formation of a new, B2 structured phase in the Ti-Mo system. The phase was observed in electron transparent material during in situ, and following ex situ, heat treatment at 300 °C. The B2 phase was enriched in Mo compared to the surrounding matrix material and formed in regular arrays of approximately square cross-section particles interspersed by thin beta channels. Electron diffraction indicated that the lattice parameter of this new phase was smaller than that of the parent phase, leading to significant strain in the beta channels. Critically, the B2 phase was only observed in material that had been electro-polished prior to heat treatment, and, therefore, it is hypothesised that this phase forms as a result of the preparation method and thin foil effects.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Synthesis, characterization and optical properties of sheet-like ZnO

Highlights: {yields} Sheet-like ZnO with regular hexagon shape was synthesized with a two-step method. {yields} Sheet-like ZnO predecessor was synthesized at low temperature in open system. {yields} The diameter and thickness of ZnO sheet can be controlled conveniently. {yields} This low-cost and environmentally benign approach is controllable and reproducible. {yields} Sheet-like ZnO may have potential application in optical and electrical devices. -- Abstract: Sheet-like ZnO with regular hexagon shape and uniform diameter has been successfully synthesized through a two-step method without any metal catalyst. First, the sheet-like ZnO precursor was synthesized in a weak alkaline carbamide environment with stirring in a constant temperature water-bath by the homogeneous precipitation method, then sheet-like ZnO was obtained by calcining at 600 {sup o}C for 2 h. The structures and optical properties of sheet-like ZnO have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) and UV-vis-NIR spectrophotometer. The results reveal that the product is highly crystalline with hexagonal wurtzite phase and has appearance of hexagon at (0 0 0 1) plane. The HRTEM images confirm that the individual sheet-like ZnO is single crystal. The PL spectrum exhibits a narrow ultraviolet emission at 397 nm and a broad visible emission centering at 502 nm. The band gap of sheet-like ZnO is about 3.15 eV.

36 MATERIALS SCIENCE↗
DOE OSTI2012

Morphology-controlled electrodeposition of Cu{sub 2}O microcrystalline particle films for application in photocatalysis under sunlight

Graphical abstract: Display Omitted Highlights: ► PEG was used to electro-deposit Cu{sub 2}O microcrystalline particle films. ► Morphologies of Cu{sub 2}O microcrystals could be controlled by the amount of PEG. ► The films showed regularly varied photocatalytic activities under sunlight. ► The films could be recycled and showed stable activities. -- Abstract: Morphology-controlled Cu{sub 2}O microcrystalline particle films had been successfully electrodeposited on tin-doped indium oxide glass substrates in CuSO{sub 4} solutions containing different amounts of polyethylene glycol (PEG) additives. With an increase of PEG, microcrystals gradually changed from irregular shapes to cubes, octahedrons, and spherical shapes. Sizes increasingly became smaller with an increase of PEG under the same deposition time. These films had been first used as recyclable photocatalysts and showed excellent and photocatalytic activities in photodegradation of methylene blue (MB) under sunlight. Activities were regularly varied relative to the morphologies of films controlled by the amount of PEG and could be further enhanced by adding a little amount of hydrogen peroxide in the MB solution. The method for controllable preparation of Cu{sub 2}O microcrystals with photocatalytic activities was simple and inexpensive. The as-prepared particle films could also be used in photodegradation of many other pollutants under sunlight.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Hydrothermal stability of SAPO-34 for refrigeration and air conditioning applications

Graphical abstract: The SAPO-34 was synthesized by a hydrothermal method using diethylamine as a template. Water adsorption strength on SAPO-34 is between that on 13X and A type silica gel. During 100–400 Pa, the water uptake on SAPO-34 increases sensitively to pressure, and equilibrium water uptake reaches 0.35 kg/kg, 25% higher than 13X. SAPO-34 shows no significant reduced cyclic water uptake over 60 cycles. Most of the initial SAPO-34 phase is restored, while the regular cubic-like morphology is well maintained, and the specific surface area only decreases by 8.6%. - Highlights: • Water adsorption strength on SAPO-34 is between that on 13X and A type silica gel. During 100–400 Pa, the water uptake on SAPO-34 increases sensitively to pressure, and equilibrium water uptake reaches 0.35 kg/kg, 25% higher than 13X. • SAPO-34 with diethylamine as the template shows no significant reduced cyclic water uptake over 60 cycles, and most of the initial SAPO-34 phase is well maintained. • SAPO-34 has an excellent adsorption performance and a good hydrothermal stability, thus is promising for application in adsorption refrigeration. - Abstract: Hydrothermal stability is one of the crucial factors in applying SAPO-34 molecular sieve to adsorption refrigration. The SAPO-34 was synthesized by a hydrothermal method using diethylamine as a template. Both a vacuum gravimetric method and an intelligent gravimetric analyzer were applied to analyze the water adsorption performance of SAPO-34. Cyclic hydrothermal performance was determined on the modified simulation adsorption refrigeration test rig. Crystal phase, morphology, and porosity of SAPO-34 were characterized by X-ray diffraction, scanning electron microscopy, and N{sub 2} sorption, respectively. The results show that, water adsorption strength on SAPO-34 is between that on 13X and A type silica gel. During 100–400 Pa, the water uptake on SAPO-34 increases sensitively to pressure, and equilibrium water uptake reaches 0.35 kg/kg, 25% higher than 13X. SAPO-34 shows no significant reduced cyclic water uptake over 60 cycles. Most of the initial SAPO-34 phase is restored, while the regular cubic-like morphology is well maintained, and the specific surface area only decreases by 8.6%.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Boron nitride hollow nanospheres: Synthesis, formation mechanism and dielectric property

Highlights: • BN hollow nanospheres are fabricated in large scale via a new CVD method. • Morphology and structure are elucidated by complementary analytical techniques. • Formation mechanism is proposed based on experimental observations. • Dielectric properties are investigated in the X-band microwave frequencies. • BN hollow nanospheres show lower dielectric loss than regular BN powders. - Abstract: Boron nitride (BN) hollow nanospheres have been successfully fabricated by pyrolyzing vapors decomposed from ammonia borane (NH{sub 3}BH{sub 3}) at 1300 °C. The final products have been extensively characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The BN hollow nanospheres were ranging from 100 to 300 nm in diameter and around 30–100 nm in thickness. The internal structure of the products was found dependent on the reaction temperatures. A possible formation mechanism of the BN hollow nanospheres was proposed on the basis of the experimental observations. Dielectric measurements in the X-band microwave frequencies (8–12 GHz) showed that the dielectric loss of the paraffin filled by the BN hollow nanospheres was lower than that filled by regular BN powders, which indicated that the BN hollow nanospheres could be potentially used as low-density fillers for microwave radomes.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Role of the chemical substitution on the luminescence properties of solid solutions Ca{sub (1−x)}Cd{sub (x)}WO{sub 4} (0 ≤ x ≤1)

Highlights: • Luminescence can be modified by chemical substitution in solid solutions Ca{sub 1−x}Cd{sub x}WO{sub 4}. • The various emission spectra (charge transfer) were obtained under X-ray excitation. • Scheelite or wolframite solid solutions presented two types of emission spectra. • A luminescence component depended on cadmium substitution in each solid solution. • A component was only characteristic of oxyanion symmetry in each solid solution. - Abstract: We have investigated the chemical substitution effects on the luminescence properties under X-ray excitation of the solid solutions Ca{sub (1−x)}Cd{sub (x)}WO{sub 4} with 0 ≤ x ≤ 1. Two types of wide spectral bands, associated with scheelite-type or wolframite-type solid solutions, have been observed at room temperature. We decomposed each spectral band into several spectral components characterized by energies and intensities varying with composition x. One Gaussian component was characterized by an energy decreasing regularly with the composition x, while the other Gaussian component was only related to the tetrahedral or octahedral configurations of tungstate groups WO{sub 4}{sup 2−} or WO{sub 6}{sup 6−}. The luminescence intensities exhibited minimum values in the composition range x < 0.5 corresponding to scheelite-type structures, then, they regularly increased for cadmium compositions x > 0.5 corresponding to wolframite-type structures.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Synthesis of Z-scheme g-C3N4/Ag/Ag3PO4 composite for enhanced photocatalytic degradation of phenol and selective oxidation of gaseous isopropanol

Highlights: • g-C3N4/Ag/Ag3PO4 composite was synthesized by a simple in situ deposition method. • Ag3PO4 nanoparticles exhibited regular rhombic dodecahedral morphology. • Photocatalyst of g-C3N4/Ag/Ag3PO4 worked under Z-scheme mechanism. • The composite showed enhanced photocatalytic activity for organics degradation. - Abstract: In this study, g-C{sub 3}N{sub 4}/Ag/Ag{sub 3}PO{sub 4} composites were constructed by a simple in situ deposition method at room temperature, in which Ag{sub 3}PO{sub 4} particles with regular rhombic dodecahedrons morphology were finely coated on the surface of the g-C{sub 3}N{sub 4} sheet. The g-C{sub 3}N{sub 4}/Ag/Ag{sub 3}PO{sub 4} exhibited much improved activity comparing with other classic catalysts such as g-C{sub 3}N{sub 4} and Ag{sub 3}PO{sub 4}. The optimal photocatalyst (AC{sub 1.0}) with Ag{sub 3}PO{sub 4}/g-C{sub 3}N{sub 4} ratio of 1 could dramatically decompose phenol under visible-light irradiation, which showed a degradation rate of 1.13 min{sup −1} and almost 60 and 2.5 times higher than that of pure g-C{sub 3}N{sub 4} and Ag/Ag{sub 3}PO{sub 4}, respectively. After 3 cycling run tests, the AC{sub 1.0} photocatalyst still maintained high photocatalytic activity. Electron paramagnetic resonance spectroscopy and radical quenching tests were employed to investigate hydroxyl and superoxide radicals for organic degradation processes. Furthermore, the photocatalytic activity of AC{sub 1.0} was also tested for gaseous isopropanol (IPA). After 4 h irradiation, 63% of IPA was oxidized with acetone as main outcome product. The highly efficient separation of photogenerated electron-hole pairs was attributed to the construction of Z-scheme mechanism.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2022

New large-strain FFT-based formulation and its application to model strain localization in nano-metallic laminates and other strongly anisotropic crystalline materials

This paper presents a new robust large-strain (LS) elasto-viscoplastic (EVP) formulation based on Fast Fourier Transforms (FFTs) for the prediction of the micro-mechanical response and microstructure evolution of polycrystalline and multiphase materials, with emphasis on the effect of strong crystallographic and/or morphologic anisotropy on localization of plastic deformation. In this work, the novel LS-EVPFFT formulation allows treatment of complex initial geometries and large deformations considering three grids of material points: a regular grid in the reference configuration, where FFTs can be performed; an irregular grid in the initial configuration, created by applying a stress-free displacement field to the reference regular grid; and an irregular grid in the current configuration, undergoing large strains and rotations as the material is loaded. Further numerical stability of the new formulation also required the use of a novel expression for the discrete modified Green’s operator, which reduces spurious field oscillations. After presenting and validating the new formulation by comparison with preexisting implementations and analytical solutions, LS-EVPFFT is applied to the prediction of slip and kink bands formation in polycrystalline columnar ice, and kink bands in single crystal zinc wires, showing good agreement with classic experiments. Finally, the model is used to study kink band formation during compression of Cu–Nb nano-metallic laminates (NMLs), in which accurate treatment of the complex geometry associated with the tortuosity of interfaces and large deformations become critical, showing consistency with corresponding micropillar experiments.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Bayesian automated weighting of aggregated DFT, MD, and experimental data for candidate thermodynamic models of aluminum with uncertainty quantification

Atomic-scale modeling methods such as density functional theory (DFT) and molecular dynamics (MD) can predict the thermodynamic properties of materials at a lower cost than experimental measurements. However, their regular usage in thermodynamic model construction is hampered by the lack of quantitative agreement with experimental measurements and the lack of uncertainty estimates on the data. To make regular usage of this atomistic simulation data, it is important to assess whether the atomistic simulation datasets, by themselves or in combination with experimental measurements, result in the same physics-informed models best supported by experimental measurements alone. Here, models of aluminum thermodynamic properties are discussed using three data sources: atomistic calculations (DFT and MD), experiments, and a combination of atomistic calculations and experiments. The study shows that, after ensuring self-consistency in predicting key invariant points, both experimental measurements and atomistic calculations can significantly contribute to an optimal model.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Actinide, Activation Product and Fission Product Decay Data for Reactor-based Applications

The UK Activation Product Decay Data Library was first released in September 1977 as UK-PADD1, to be followed by regular improvements on an almost yearly basis up to the assembly of UKPADD6.12 in March 2013. Similarly, the UK Heavy Element and Actinide Decay Data Library followed in December 1981 as UKHEDD1, with the implementation of various modifications leading to UKHEDD2.6, February 2008. Both the data content and evaluation procedures are defined, and the most recent evaluations are described in terms of specific radionuclides and the resulting consistency of their recommended decay-data files. New versions of the UKPADD and UKHEDD libraries are regularly submitted to the NEA Data Bank for possible inclusion in the JEFF library.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2017

The Majorana Demonstrator calibration system

The Majorana Collaboration is searching for the neutrinoless double-beta decay of the nucleus 76 Ge. The Majorana Demonstrator is an array of germanium detectors deployed with the aim of implementing background reduction techniques suitable for a 1-ton 76 Ge-based search. The ultra low-background conditions require regular calibrations to verify proper function of the detectors. Radioactive line sources can be deployed around the cryostats containing the detectors for regular energy calibrations. When measuring in low-background mode, these line sources have to be stored outside the shielding so they do not contribute to the background. The deployment and the retraction of the source are designed to be controlled by the data acquisition system and do not require any direct human interaction. In this study, we detail the design requirements and implementation of the calibration apparatus, which provides the event rates needed to define the pulse-shape cuts and energy calibration used in the final analysis as well as data that can be compared to simulations.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2024

Measurement of seasonal variations of the NSLS-II circumference and energy

Routine beam-based characterization of the NSLS-II storage ring indicated probable seasonal variations of the ring circumference and energy. We arranged regular direct measurements of the ring circumference during 2023 and compared the results with the archived data of the magnet and undulator settings. A clear correlation between the ring circumference and energy was observed. These seasonal variations of the ring energy are found to be the main reason for regular lattice corrections required to keep the machine performance stable for user operations. Finally, the measurement techniques and results are discussed in this article.

36 MATERIALS SCIENCE↗
DOE OSTI2015

An improved understanding of the natural resonances of moonpools contained within floating rigid-bodies: Theory and application to oscillating water column devices

The fundamental interactions between waves, a floating rigid-body, and a moonpool that is selectively open to atmosphere or enclosed to purposefully induce pressure fluctuations are investigated. The moonpool hydrodynamic characteristics and the hydrodynamic coupling to the rigid-body are derived implicitly through reciprocity relations on an array of field points. By modeling the free surface of the moonpool in this manner, an explicit hydrodynamic coupling term is included in the equations of motion. This coupling results in the migration of the moonpool's natural resonance frequency from the piston frequency to a new frequency when enclosed in a floating rigid-body. Two geometries that highlight distinct aspects of marine vessels and oscillating water column (OWC) renewable energy devices are analyzed to reveal the coupled natural resonance migration. The power performance of these two OWCs in regular waves is also investigated. The air chamber is enclosed and a three-dimensional, linear, frequency domain performance model that links the rigid-body to the moonpool through a linear resistive control strategy is detailed. Furthermore, an analytic expression for the optimal linear resistive control values in regular waves is presented.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗