High Volume Submersible Electric Pumps, Design Considerations and Operations

2018 ◽  
Author(s):  
F. B. Langitan
Keyword(s):  
High Volume ◽  
Design Considerations

Morphology, Distribution and Identification of Micro-Constituents Along Grain Boundaries in Nickel-Base Alloys

1973 ◽  
Vol 31 ◽  
pp. 176-177
Author(s):  
D. E. Fornwalt ◽  
A. R. Geary ◽  
B. H. Kear
Keyword(s):  
Electron Microscope ◽  
Grain Boundaries ◽  
Volume Fraction ◽  
Rupture Life ◽  
Stress Rupture ◽  
High Volume ◽  
Precipitate Morphology ◽  
Stress Rupture Life ◽  
Nickel Base ◽  
Scanning Electron

A systematic study has been made of the effects of various heat treatments on the microstructures of several experimental high volume fraction γ’ precipitation hardened nickel-base alloys, after doping with ∼2 w/o Hf so as to improve the stress rupture life and ductility. The most significant microstructural chan§e brought about by prolonged aging at temperatures in the range 1600°-1900°F was the decoration of grain boundaries with precipitate particles.Precipitation along the grain boundaries was first detected by optical microscopy, but it was necessary to use the scanning electron microscope to reveal the details of the precipitate morphology. Figure 1(a) shows the grain boundary precipitates in relief, after partial dissolution of the surrounding γ + γ’ matrix.

A Comparison of Tem and Apfim to the Interpretation of Modulated Microstructures

1985 ◽  
Vol 43 ◽  
pp. 70-71
Author(s):  
M.G. Burke ◽  
M.K. Miller
Keyword(s):  
Low Temperature ◽  
Microstructural Characterization ◽  
Superlattice Reflection ◽  
High Volume ◽  
Atom Probe ◽  
Dark Field ◽  
Miscibility Gap ◽  
Second Phase ◽  
Two Phase ◽  
Probe Field

Interpretation of fine-scale microstructures containing high volume fractions of second phase is complex. In particular, microstructures developed through decomposition within low temperature miscibility gaps may be extremely fine. This paper compares the morphological interpretations of such complex microstructures by the high-resolution techniques of TEM and atom probe field-ion microscopy (APFIM).The Fe-25 at% Be alloy selected for this study was aged within the low temperature miscibility gap to form a <100> aligned two-phase microstructure. This triaxially modulated microstructure is composed of an Fe-rich ferrite phase and a B2-ordered Be-enriched phase. The microstructural characterization through conventional bright-field TEM is inadequate because of the many contributions to image contrast. The ordering reaction which accompanies spinodal decomposition in this alloy permits simplification of the image by the use of the centered dark field technique to image just one phase. A CDF image formed with a B2 superlattice reflection is shown in fig. 1. In this CDF micrograph, the the B2-ordered Be-enriched phase appears as bright regions in the darkly-imaging ferrite. By examining the specimen in a [001] orientation, the <100> nature of the modulations is evident.

Morphological behavior of compatibilized ternary blends prepared by mechanical mixing

1993 ◽  
Vol 51 ◽  
pp. 1200-1201
Author(s):  
S.D. Smith ◽  
R.J. Spontak ◽  
D.H. Melik ◽  
S.M. Buehler ◽  
K.M. Kerr ◽  
...  
Keyword(s):  
Interfacial Adhesion ◽  
Diblock Copolymers ◽  
Ternary Blends ◽  
Mechanical Mixing ◽  
Design Considerations ◽  
Covalently Bonded ◽  
Homopolymer Blends ◽  
Emulsifying Agent ◽  
Surface Active ◽  
Low Entropy

When blended together, homopolymers A and B will normally macrophase-separate into relatively large (≫1 μm) A-rich and B-rich phases, between which exists poor interfacial adhesion, due to a low entropy of mixing. The size scale of phase separation in such a blend can be reduced, and the extent of interfacial A-B contact and entanglement enhanced, via addition of an emulsifying agent such as an AB diblock copolymer. Diblock copolymers consist of a long sequence of A monomers covalently bonded to a long sequence of B monomers. These materials are surface-active and decrease interfacial tension between immiscible phases much in the same way as do small-molecule surfactants. Previous studies have clearly demonstrated the utility of block copolymers in compatibilizing homopolymer blends and enhancing blend properties such as fracture toughness. It is now recognized that optimization of emulsified ternary blends relies upon design considerations such as sufficient block penetration into a macrophase (to avoid block slip) and prevention of a copolymer multilayer at the A-B interface (to avoid intralayer failure).

Theoretical And Practical Design Considerations for Ultra-High Resolution Electron Lenses

1980 ◽  
Vol 38 ◽  
pp. 266-269
Author(s):  
Y. Harada ◽  
K. Tsuno ◽  
Y. Arai
Keyword(s):  
Optical Properties ◽  
High Resolution ◽  
Chromatic Aberration ◽  
Point Of View ◽  
Pole Piece ◽  
Axial Field ◽  
Design Considerations ◽  
Resolution Electron ◽  
Practical Design ◽  
Peak Flux

Magnetic objective lenses, from the point of view of pole piece geometry, can he roughly classified into two types, viz., symmetrical and asymmetrical. In the case of the former, the optical properties have been calculated by several authors1-3) and the results would appear to suggest that, in order to reduce the spherical and chromatic aberration coefficients, Cs and Cc, it is necessary to decrease the half-width value of the axial field distribution and to increase the peak flux density. The expressions for either minimum Cs or minimum Cc were presented in the form of ‘universal’ curves by Mulvey and Wallington4).

1002: Long Term Outcomes for Patients with High Volume Retroperitoneal Teratoma Undergoing Post Chemotherapy Surgery

2007 ◽  
Vol 177 (4S) ◽  
pp. 331-331 ◽  
Author(s):  
Stephen D.W. Beck ◽  
Richard S. Foster ◽  
Richard Bihrle ◽  
John P. Donohue
Keyword(s):  
High Volume ◽  
Long Term Outcomes ◽  
Retroperitoneal Teratoma

23: High Volume Hospitals do not have Better Long Term Outcomes Following Cystectomy for Bladder Cancer

2006 ◽  
Vol 175 (4S) ◽  
pp. 8-9 ◽  
Author(s):  
Brent K. Hollenbeck ◽  
Yongliang Wei ◽  
John D. Birkmeyer
Keyword(s):  
Bladder Cancer ◽  
High Volume ◽  
Long Term Outcomes

A randomized cross-over trial in patients suspected of PAD on diagnostic accuracy of ankle-brachial index by Doppler-based versus four-point oscillometry based measurements

VASA ◽  
2019 ◽  
Vol 48 (6) ◽  
pp. 516-522 ◽  
Author(s):  
Verena Mayr ◽  
Mirko Hirschl ◽  
Peter Klein-Weigel ◽  
Luka Girardi ◽  
Michael Kundi
Keyword(s):  
Diagnostic Accuracy ◽  
Ankle Brachial Index ◽  
Area Under The Curve ◽  
High Volume ◽  
Epidemiologic Studies ◽  
Lower Sensitivity ◽  
Oscillometric Device ◽  
Specificity And Sensitivity ◽  
Time Requirements ◽  
Peripheral Arterial

Summary. Background: For diagnosis of peripheral arterial occlusive disease (PAD), a Doppler-based ankle-brachial-index (dABI) is recommended as the first non-invasive measurement. Due to limitations of dABI, oscillometry might be used as an alternative. The aim of our study was to investigate whether a semi-automatic, four-point oscillometric device provides comparable diagnostic accuracy. Furthermore, time requirements and patient preferences were evaluated. Patients and methods: 286 patients were recruited for the study; 140 without and 146 with PAD. The Doppler-based (dABI) and oscillometric (oABI and pulse wave index – PWI) measurements were performed on the same day in a randomized cross-over design. Specificity and sensitivity against verified PAD diagnosis were computed and compared by McNemar tests. ROC analyses were performed and areas under the curve were compared by non-parametric methods. Results: oABI had significantly lower sensitivity (65.8%, 95% CI: 59.2%–71.9%) compared to dABI (87.3%, CI: 81.9–91.3%) but significantly higher specificity (79.7%, 74.7–83.9% vs. 67.0%, 61.3–72.2%). PWI had a comparable sensitivity to dABI. The combination of oABI and PWI had the highest sensitivity (88.8%, 85.7–91.4%). ROC analysis revealed that PWI had the largest area under the curve, but no significant differences between oABI and dABI were observed. Time requirement for oABI was significantly shorter by about 5 min and significantly more patients would prefer oABI for future testing. Conclusions: Semi-automatic oABI measurements using the AngER-device provide comparable diagnostic results to the conventional Doppler method while PWI performed best. The time saved by oscillometry could be important, especially in high volume centers and epidemiologic studies.

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