Photo-embossed Surface Relief Structures with an Increased Aspect Ratio by Addition of Kinetic Interfering Compounds

Slip localization is often observed in metallic polycrystals after cyclic deformation (persistent slip bands) or pre-irradiation followed by tensile deformation (channels). To evaluate its influence on surface relief formation and grain boundary microcrack nucleation, crystalline finite element (FE) computations are carried out using microstructure inputs (slip band aspect ratio/spacing). Slip bands (low critical resolved shear stress (CRSS)) are embedded in small elastic aggregates. Slip band aspect ratio and neighboring grain orientations influence strongly the surface slips. But only a weak effect of slip band CRSS, spacing and grain boundary orientation is observed. Analytical formulae are deduced which allow an easy prediction of the surface and bulk slips. The computed slips are in agreement with experimental measures (AFM/TEM measures on pre-irradiated austenitic stainless steels and nickel, copper and precipitate-strengthened alloy subjected to cyclic loading). Grain boundary normal stresses are computed for various materials and loading conditions. A square root dependence with respect to the distance to the slip band corner is found similarly to the pile-up stress field. But the equivalent stress intensity factor is considerably lower. Analytical formulae are proposed for predicting the grain boundary normal stress field depending on the microstructure lengths. Finally, an energy balance criterion is applied using the equivalent elastic energy release rate and the surface/grain boundary energies. The predicted macroscopic stresses for microcrack nucleation are compared to the experimental ones.

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Fabrication of GaSb Microlenses by Photo and E-Beam Lithography and Dry Etching

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.99-100.83 ◽

2004 ◽

Vol 99-100 ◽

pp. 83-88 ◽

Cited By ~ 1

Author(s):

E. Papis ◽

Anna Piotrowska ◽

T.T. Piotrowski ◽

K. Gołaszewska ◽

L. Ilka ◽

...

Keyword(s):

Aspect Ratio ◽

Surface Relief ◽

Optoelectronic Devices ◽

Dry Etching ◽

Mid Infrared ◽

Gasb Substrate ◽

Sputter Etching

Fabrication of surface-relief microstructures in GaSb for application in mid-infrared optoelectronic devices is described. Photo- and e-beam lithography was used to define patterns on GaSb surfaces. Ar/O2 sputter etching and RIE in BCl3-based plasma were applied to transfer preshaped master into the GaSb substrate. Circular microlenses with an aspect ratio (height to diameter) 0.4/10 µm and circular gratings with 0.4 µm linewidth / 1 µm period and 1.7 µm depth have been demonstrated.

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High aspect ratio surface relief structures by photoembossing

Applied Physics Letters ◽

10.1063/1.2799744 ◽

2007 ◽

Vol 91 (17) ◽

pp. 174103 ◽

Cited By ~ 22

Author(s):

Ko Hermans ◽

Florian K. Wolf ◽

Jolke Perelaer ◽

Rene A. J. Janssen ◽

Ulrich S. Schubert ◽

...

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Surface Relief

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X-ray Gabor holography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139433 ◽

1995 ◽

Vol 53 ◽

pp. 612-613

Author(s):

Steve Lindaas ◽

Chris Jacobsen ◽

Alex Kalinovsky ◽

Malcolm Howells

Keyword(s):

Surface Relief ◽

Biological Imaging ◽

Specimen Preparation ◽

X Rays ◽

X Ray ◽

Water Window ◽

Biological Objects ◽

Transmission Imaging ◽

Atomic Force ◽

Electron Microscopes

Soft x-ray microscopy offers an approach to transmission imaging of wet, micron-thick biological objects at a resolution superior to that of optical microscopes and with less specimen preparation/manipulation than electron microscopes. Gabor holography has unique characteristics which make it particularly well suited for certain investigations: it requires no prefocussing, it is compatible with flash x-ray sources, and it is able to use the whole footprint of multimode sources. Our method serves to refine this technique in anticipation of the development of suitable flash sources (such as x-ray lasers) and to develop cryo capabilities with which to reduce specimen damage. Our primary emphasis has been on biological imaging so we use x-rays in the water window (between the Oxygen-K and Carbon-K absorption edges) with which we record holograms in vacuum or in air.The hologram is recorded on a high resolution recording medium; our work employs the photoresist poly(methylmethacrylate) (PMMA). Following resist “development” (solvent etching), a surface relief pattern is produced which an atomic force microscope is aptly suited to image.

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Perceptual and Emotional Responses as a Function of Film Aspect Ratio as Viewed on a Television Screen

PsycEXTRA Dataset ◽

10.1037/e413782005-390 ◽

1999 ◽

Author(s):

Norman G. Gordon ◽

Michael J. Johnson

Keyword(s):

Aspect Ratio ◽

Emotional Responses ◽

Television Screen

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Modification of MnS inclusion by tellurium in 38MnVS6 micro-alloyed steel

Metallurgical Research & Technology ◽

10.1051/metal/2020066 ◽

2020 ◽

Vol 117 (6) ◽

pp. 615

Author(s):

Ping Shen ◽

Lei Zhou ◽

Qiankun Yang ◽

Zhiqi Zeng ◽

Kenan Ai ◽

...

Keyword(s):

Fatigue Life ◽

Aspect Ratio ◽

Strong Influence ◽

Experimental Results ◽

Alloyed Steel ◽

Equivalent Diameter ◽

Small Aspect Ratio ◽

Steel Quality ◽

Eds Analysis ◽

Micro Alloyed Steel

In 38MnVS6 steel, the morphology of sulfide inclusion has a strong influence on the fatigue life and machinability of the steel. In most cases, the MnS inclusions show strip morphology after rolling, which significantly affects the steel quality. Usually, the MnS inclusion with a spherical morphology is the best morphology for the steel quality. In the present work, tellurium was applied to 38MnVS6 micro-alloyed steel to control the MnS inclusion. Trace tellurium was added into 38MnVS6 steel and the effect of Te on the morphology, composition, size and distribution of MnS inclusions were investigated. Experimental results show that with the increase of Te content, the equivalent diameter and the aspect ratio of inclusion decrease strikingly, and the number of inclusions with small aspect ratio increases. The inclusions are dissociated and spherized. The SEM-EDS analysis indicates that the trace Te mainly dissolves in MnS inclusion. Once the MnS is saturated with Te, MnTe starts to generate and wraps MnS. The critical Te/S value for the formation of MnTe in the 38MnV6 steel is determined to be approximately 0.075. With the increase of Te/S ratio, the aspect ratio of MnS inclusion decreases and gradually reaches a constant level. The Te/S value in the 38MnVS6 steel corresponding to the change of aspect ratio from decreasing to constant ranges from 0.096 to 0.255. This is most likely to be caused by the saturation of Te in the MnS inclusion. After adding Te in the steel, rod-like MnS inclusion is modified to small inclusion and the smaller the MnS inclusion, the lower the aspect ratio.

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PENINGKATAN KEMAMPUAN GURU BAHASA INDONESIA DALAM MENYUSUN RENCANA PROGRAM PEMBELAJARAN (RPP) SDN 015 PAGARAN TAPAH DARUSSALAM MELALUI METODE PEMBERIAN TUGAS

Primary: Jurnal Pendidikan Guru Sekolah Dasar ◽

10.33578/jpfkip.v5i3.3956 ◽

2017 ◽

Vol 5 (3) ◽

pp. 713

Author(s):

Mukhlis '

Keyword(s):

Aspect Ratio ◽

Duty Cycle ◽

Lesson Plans ◽

Learning Program ◽

School Subjects ◽

Bahasa Indonesia

Based on the observation of some teachers found the symptoms as follows: the lack of abilityof Indonesian teachers in designing learning program (RPP), the learning device is only usedas a supplement and not to the needs of teaching, most teachers again if asked the lessonanswered not have or has not been made. The purpose of this research is to improve theability of Indonesian teachers in designing learning program (RPP) at SDN 015 PagaranTapah Darussalam through the method of administration tasks. This type of research is actionresearch school. Subjects in this study were teachers Indonesian as many as 12 people. Basedon the analysis and discussion can be concluded that the method of administration tasks canimprove the ability of Indonesian teachers in making learning device in SDN 015 PagaranTapah Darussalam through the method of administration tasks. Under these conditions, thelevel of acceptance of teachers increased. The aspect ratio capability Indonesian teachers inpreparing lesson plans through the provision of duty cycle I and II of the increase from 56%and the second cycle to 79%.

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