Design and characterization of a polymer electrothermal microgripper with a polynomial flexure for efficient operation and studies of moisture effect on negative deflection

2020 ◽  
Author(s):  
Alissa Potekhina ◽  
Rodica-Cristina Voicu ◽  
Raluca Muller ◽  
Muaiyd H. M. Al-Zandi ◽  
Changhai Wang
Keyword(s):  
Efficient Operation ◽  
Moisture Effect ◽  
Negative Deflection

Characterization of Hemodynamic Performance and Degree of Flow Redirection in the Left Ventricle Dependent on the Mitral Mechanical Heart Valve Orientation

2002 ◽  
Author(s):  
Olga Pierrakos ◽  
Pavlos P. Vlachos ◽  
Demetri P. Telionis ◽  
Saami Yazdani ◽  
Ali Etebari
Keyword(s):  
Left Ventricle ◽  
Heart Valve ◽  
Mechanical Heart Valve ◽  
Efficient Operation ◽  
Flow Disturbances ◽  
Energy Conserving ◽  
Flow Through ◽  
Healthy Functioning ◽  
Hemodynamic Performance

Recent groundbreaking work by Kilner et al. [1] demonstrated that a healthy functioning heart redirects the flow through the left ventricle (LV) in an asymmetric manner, which results in an energy conserving mechanism. Heart valve replacement alters the physiological operation of the heart significantly affecting its hemodynamic performance. As a result, orientation and valve design could play a significant role in the energy efficient operation of the heart; therefore, orienting MHVs so that flow disturbances are minimized enhances the hemodynamic performance of the LV.

Characterization of textile wastewater and other industrial wastewaters by respirometric and titration biosensors

1999 ◽  
Vol 40 (1) ◽  
pp. 161-168 ◽  
Author(s):  
A. Rozzi ◽  
E. Ficara ◽  
C. M. Cellamare ◽  
G. Bortone
Keyword(s):  
Industrial Wastewater ◽  
Wastewater Treatment Plants ◽  
Oxygen Uptake Rate ◽  
Industrial Effluents ◽  
Textile Wastewater ◽  
Efficient Operation ◽  
Autotrophic Bacteria ◽  
Degradation Rates ◽  
Wastewater Samples

Many industrial effluents, such as textile and tannery wastewater, contain slowly biodegradable, refractory or even toxic compounds at variable concentrations which may interfere with the efficient operation of biological wastewater treatment plants, in particular with the nitrification stage. Agro-industrial effluents may occasionally contain sanitising agents which are by definition biocides. Two different biosensors, based on respirometry (oxygen uptake rate, OUR measurements) and on basic titration respectively, were used to measure degradation rates of industrial wastewater samples by autotrophic bacteria (ammonia oxidizers). Specific sanitisers such as sodium hypochlorite and benzalconium chloride were used to evaluate and compare the nitrifying activity measured by the two different instruments.

Computational Analysis and Characterization of Cockpit Environmental Control System of a Fighter Aircraft in Humid Environment

2014 ◽  
Vol 629 ◽  
pp. 263-269 ◽  
Author(s):  
Muhammad Ayaz ◽  
J. Masud
Keyword(s):  
Control System ◽  
Computational Analysis ◽  
Environmental Control ◽  
Great Flexibility ◽  
Fighter Aircraft ◽  
Efficient Operation ◽  
Analysis Techniques ◽  
Humid Environment ◽  
Computational Fluid Dynamics Cfd

he Environmental Control System (ECS) is an important part of any fighter aircraft and has far reaching repercussions in terms of its capability to operate as an effective weapon system under adverse weatherconditions. The aircrew and majority of electronics depend on ECS to keep temperature, pressure and humidity levels within acceptable limits for efficient operation. These limits are explicitly defined in relevant MIL standards MIL-E-18927E(AS)[1]. In order to thoroughly analyze the ECS of under study aircraft[2, 3], Computational Fluid Dynamics (CFD) analysis techniques have been used. CFD techniques offer great flexibility since various conditions can be simulated and analyzed results can be used for required improvements in the system.

Characterization of Calcium Hydroxide Derived from Waste Eggshell upon Moisture Effect

2014 ◽  
Vol 979 ◽  
pp. 435-439 ◽  
Author(s):  
W. Siriprom ◽  
K. Teanchai ◽  
K. Kirdsiri ◽  
J. Kaewkhao
Keyword(s):  
Calcium Hydroxide ◽  
X Rays ◽  
X Ray Diffraction ◽  
Oxide Compound ◽  
Water Steam ◽  
Moisture Effect ◽  
X Ray ◽  
Different Temperatures ◽  
Chicken Eggshell

The structural transformations of chicken eggshell sample upon heat treatments and water absorption have been studied after having ground the shells into powders. Structural identifications of chicken eggshell samples were performed by using x-ray diffraction, IR spectroscopy and Energy Dispersive X-rays spectrometer (EDXRF). It was found that the specimen is made of calcite, a common phase of CaCO3 mineral. An then annealing at different temperatures in the range of 300-600C, The chicken eggshell not transformation, but after heat treatment at temperature 900C, the chicken eggshell sample have been transform structural in to oxide compound with calcia phase. In addition, the chicken eggshells have been preparation calcium hydroxide via a water steam route.

Morphological Characterization of Mycobacteriophage R1

1974 ◽  
Vol 32 ◽  
pp. 254-255
Author(s):  
B. L. Soloff ◽  
T. A. Rado
Keyword(s):  
Carbon Source ◽  
Stationary Phase ◽  
Growth Phase ◽  
Minimal Medium ◽  
Morphological Characterization ◽  
Logarithmic Growth Phase ◽  
Complete Lysis ◽  
Lysogenic Culture ◽  
Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

AEM analysis of crystallization in Ti-based amorphous alloys

1983 ◽  
Vol 41 ◽  
pp. 270-271
Author(s):  
A.R. Pelton ◽  
A.F. Marshall ◽  
Y.S. Lee
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloys ◽  
Amorphous Materials ◽  
Isothermal Annealing ◽  
Amorphous Matrix ◽  
Nucleation And Growth ◽  
Current Interest ◽  
Amorphous Films ◽  
Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

Characterization of Coherent, Ordered Precipitates in Nickel-Base Alloys

1973 ◽  
Vol 31 ◽  
pp. 144-145
Author(s):  
B. H. Kear ◽  
J. M. Oblak
Keyword(s):  
Stable Phase ◽  
Nickel Base Superalloy ◽  
Alloy 718 ◽  
Commercial Alloy ◽  
Precipitate Morphology ◽  
Continuous Precipitation ◽  
Nickel Base ◽  
Base Superalloy ◽  
Strengthening Precipitate

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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