A MENAGERIE OF INTERFACE STRUCTURES IN COPOLYMER SYSTEMS

Cu-Cr age-hardening alloys are of interest as a model system for the investigation of fcc/bcc interface structures. Several past studies have investigated the morphology and interface structure of Cr precipitates in a Cu matrix (1-3) and good success has been achieved in understanding the crystallography and strain contrast of small needle-shaped precipitates. The present study investigates the effect of small amounts of phosphorous on the precipitation behavior of Cu-Cr alloys.The same Cu-0.3% Cr alloy as was used in earlier work was rolled to a thickness of 150 μm, solution treated in vacuum at 1050°C for 1h followed by quenching and annealing for various times at 820 and 863°C.Two laths and their corresponding diffraction patterns in an alloy aged 2h at 820°C are shown in correct relative orientation in Fig. 1. To within the limit of accuracy of the diffraction patterns the orientation relationship was that of Kurdjumov-Sachs (KS), i.e. parallel close-packed planes and directions.

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Interface structures in polycrystalline ceramic materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143900 ◽

1986 ◽

Vol 44 ◽

pp. 468-471

Author(s):

K. J. Morrissey

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Physical And Mechanical Properties ◽

High Resolution Electron Microscopy ◽

Ceramic Materials ◽

Polycrystalline Materials ◽

Transmission Electron ◽

Resolution Electron ◽

Interface Structures

Grain boundaries and interfaces play an important role in determining both physical and mechanical properties of polycrystalline materials. To understand how the structure of interfaces can be controlled to optimize properties, it is necessary to understand and be able to predict their crystal chemistry. Transmission electron microscopy (TEM), analytical electron microscopy (AEM,), and high resolution electron microscopy (HREM) are essential tools for the characterization of the different types of interfaces which exist in ceramic systems. The purpose of this paper is to illustrate some specific areas in which understanding interface structure is important. Interfaces in sintered bodies, materials produced through phase transformation and electronic packaging are discussed.

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Growth of hematite on (0001) and {1102} sapphire substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175016 ◽

1990 ◽

Vol 48 (4) ◽

pp. 376-377

Author(s):

Lisa A. Tietz ◽

Scott R. Summerfelt ◽

C. Barry Carter

Keyword(s):

Imaging Techniques ◽

Chemical Vapor ◽

Interface Energy ◽

Dark Field ◽

Cation Sublattice ◽

Sapphire Substrates ◽

Dark Field Imaging ◽

Weak Beam ◽

Pressure Chemical ◽

Interface Structures

Defects in thin films are often introduced at the substrate-film interface during the early stages of growth. The interface structures of semiconductor heterojunctions have been extensively studied because of the electrical activity of defects in these materials. Much less attention has been paid to the structure of oxide-oxide heterojunctions. In this study, the structures of the interfaces formed between hematite (α-Fe2O3) and two orientations of sapphire (α-Al2O3) are examined in relationship to the defects introduced into the hematite film. In such heterojunctions, the oxygen sublattice is expected to have a strong influence on the epitaxy; however, defects which involve only the cation sublattice may be introduced at the interface with little increase in interface energy.Oxide heterojunctions were produced by depositing small quantities of hematite directly onto electrontransparent sapphire substrates using low-pressure chemical vapor deposition. Prior to deposition, the ionthinned substrates were chemically cleaned and annealed at 1400°C to give “clean”, crystalline surfaces. Hematite was formed by the reaction of FeCl3 vapor with water vapor at 1150°C and 1-2 Torr. The growth of the hematite and the interface structures formed on (0001) and {102} substrates have been studied by bright-field, strong- and weak-beam dark-field imaging techniques.

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Interface Structures and Electronic States of Epitaxial Tetraazanaphthacene on Single-Crystal Pentacene

Materials ◽

10.3390/ma14051088 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1088

Author(s):

Yuki Gunjo ◽

Hajime Kamebuchi ◽

Ryohei Tsuruta ◽

Masaki Iwashita ◽

Kana Takahashi ◽

...

Keyword(s):

Single Crystal ◽

Photoelectron Spectroscopy ◽

Grazing Incidence ◽

Force Microscopy ◽

Interface Dipole ◽

Atomic Force ◽

Interfacial Structures ◽

Donor And Acceptor ◽

A Charge ◽

Interface Structures

The structural and electronic properties of interfaces composed of donor and acceptor molecules play important roles in the development of organic opto-electronic devices. Epitaxial growth of organic semiconductor molecules offers a possibility to control the interfacial structures and to explore precise properties at the intermolecular contacts. 5,6,11,12-tetraazanaphthacene (TANC) is an acceptor molecule with a molecular structure similar to that of pentacene, a representative donor material, and thus, good compatibility with pentacene is expected. In this study, the physicochemical properties of the molecular interface between TANC and pentacene single crystal (PnSC) substrates were analyzed by atomic force microscopy, grazing-incidence X-ray diffraction (GIXD), and photoelectron spectroscopy. GIXD revealed that TANC molecules assemble into epitaxial overlayers of the (010) oriented crystallites by aligning an axis where the side edges of the molecules face each other along the [1¯10] direction of the PnSC. No apparent interface dipole was found, and the energy level offset between the highest occupied molecular orbitals of TANC and the PnSC was determined to be 1.75 eV, which led to a charge transfer gap width of 0.7 eV at the interface.

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Analytical electron microscopy of ( 2 ¯ 01) β-Ga2O3/SiO2 and ( 2 ¯ 01) β-Ga2O3/Al2O3 interface structures in MOS capacitors

Journal of Applied Physics ◽

10.1063/5.0041266 ◽

2021 ◽

Vol 129 (19) ◽

pp. 195705

Author(s):

Christopher J. Klingshirn ◽

Asanka Jayawardena ◽

Sarit Dhar ◽

Rahul P. Ramamurthy ◽

Dallas Morisette ◽

...

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Mos Capacitors ◽

Analytical Electron ◽

Interface Structures

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Effect of chemical modification on electronic transport properties of carbyne

Journal of Computational Electronics ◽

10.1007/s10825-020-01639-7 ◽

2021 ◽

Author(s):

G. R. Berdiyorov ◽

U. Khalilov ◽

H. Hamoudi ◽

Erik C. Neyts

Keyword(s):

Transport Properties ◽

Electronic Transport ◽

Density Functional ◽

Structural Changes ◽

Carbon Chain ◽

Functional Formalism ◽

Functional Theory ◽

Carbon Allotrope ◽

Electronic Transport Properties ◽

Interface Structures

AbstractUsing density functional theory in combination with the Green’s functional formalism, we study the effect of surface functionalization on the electronic transport properties of 1D carbon allotrope—carbyne. We found that both hydrogenation and fluorination result in structural changes and semiconducting to metallic transition. Consequently, the current in the functionalization systems increases significantly due to strong delocalization of electronic states along the carbon chain. We also study the electronic transport in partially hydrogenated carbyne and interface structures consisting of pristine and functionalized carbyne. In the latter case, current rectification is obtained in the system with rectification ratio up to 50%. These findings can be useful for developing carbyne-based structures with tunable electronic transport properties.

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Nano carbon supported platinum catalyst interaction behavior with perfluorosulfonic acid ionomer and their interface structures

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2015.07.049 ◽

2016 ◽

Vol 181 ◽

pp. 146-155 ◽

Cited By ~ 19

Author(s):

Shuang Ma Andersen

Keyword(s):

Platinum Catalyst ◽

Perfluorosulfonic Acid ◽

Supported Platinum ◽

Interaction Behavior ◽

Nano Carbon ◽

Supported Platinum Catalyst ◽

Interface Structures

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Trends in Solute Segregation Behavior During Silicon Solidification

MRS Proceedings ◽

10.1557/proc-321-479 ◽

1993 ◽

Vol 321 ◽

Cited By ~ 1

Author(s):

Riccardo Reitanot ◽

Patrick M. Smith ◽

Michael J. Aziz

Keyword(s):

Crystal Growth ◽

Inverse Correlation ◽

High Growth ◽

Orientation Dependence ◽

Solute Trapping ◽

Group Iii ◽

Explosive Crystallization ◽

Crystallization Speed ◽

Crystal Growth Kinetics ◽

Interface Structures

ABSTRACTAt the high growth rates accessible during pulsed-laser induced melting and solidification and explosive crystallization, crystal growth kinetics are dominated not by equilibrium thermodynamics, but by the atomistic mechanisms by which crystallization proceeds. These Mechanisms can be probed by testing the predictions of solute trapping models based on various crystal/Melt interface structures against Measurements. We have measured the dependence of solute trapping of several group III, IV, and V elements in silicon on both interface orientation and crystallization speed. The Aperiodic Stepwise Growth Model of Goldman and Aziz accurately fits both the velocity and orientation dependence of the solute trapping observed in these systems. The success of the model implies a ledge structure for the crystal/Melt interface and a step-flow mechanism for crystal growth. In addition, we have observed an empirical inverse correlation between the two free parameters (“diffusive speeds”) in this model and the equilibrium solute partition coefficient of a system. This correlation may be used to estimate values of the diffusive speeds for other systems in which solute trapping has not been or cannot be Measured.

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What is the source of L1 attrition? The effect of recent L1 re-exposure on Spanish speakers under L1 attrition

Bilingualism Language and Cognition ◽

10.1017/s1366728915000152 ◽

2015 ◽

Vol 19 (3) ◽

pp. 520-532 ◽

Cited By ~ 39

Author(s):

GLORIA CHAMORRO ◽

ANTONELLA SORACE ◽

PATRICK STURT

Keyword(s):

Eye Tracking ◽

Spanish Speakers ◽

Control Group ◽

Tracking Data ◽

Native Spanish Speakers ◽

Knowledge Representations ◽

Permanent Change ◽

L1 Attrition ◽

Interface Structures

The recent hypothesis that L1 attrition affects the ability to process interface structures but not knowledge representations (Sorace, 2011) is tested by investigating the effects of recent L1 re-exposure on antecedent preferences for Spanish pronominal subjects, using offline judgements and online eye-tracking measures. Participants included a group of native Spanish speakers experiencing L1 attrition (‘attriters’), a second group of attriters exposed exclusively to Spanish before they were tested (‘re-exposed’), and a control group of Spanish monolinguals. The judgement data shows no significant differences between the groups. Moreover, the monolingual and re-exposed groups are not significantly different from each other in the eye-tracking data. The results of this novel manipulation indicate that attrition effects decrease due to L1 re-exposure, and that bilinguals are sensitive to input changes. Taken together, the findings suggest that attrition affects online sensitivity with interface structures rather than causing a permanent change in speakers’ L1 knowledge representations.

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